JP3906722B2

JP3906722B2 - Contactless power supply system

Info

Publication number: JP3906722B2
Application number: JP2002086289A
Authority: JP
Inventors: 秀明安倍; 猛児島; 嘉志記桂; 幹弘山下
Original assignee: Matsushita Electric Works Ltd
Current assignee: Panasonic Electric Works Co Ltd
Priority date: 2002-03-26
Filing date: 2002-03-26
Publication date: 2007-04-18
Anticipated expiration: 2022-03-26
Also published as: JP2003284264A

Description

【０００１】
【発明の属する技術分野】
本発明は、非接触給電システムに関するものである。
【０００２】
【従来の技術】
近年、携帯用電子機器や電気自動車、産業機器等への非接触電力伝達技術の採用が広がっている。特に電動歯ブラシや電気シェーバ等の水まわりで使う商品には、この技術が重宝される。電力供給側（給電側）と負荷側（受電側）とを着脱して用いる非接触給電システムにおいて、電力供給側から負荷側に電磁誘導により電力を供給する場合、負荷側が外されているときには電力供給側インバータ回路で用いる発振用のスイッチング素子の発振を停止、または発振強度の低減を行う必要がある。この理由は、負荷がない場合に発振を継続させると、電力供給側の電力損失によりエネルギーの無駄使いになってしまうからであり、また、正しい負荷以外の例えば金属異物が置かれれば、誘導加熱作用により、金属の異常過熱を生じ危険であるからである。さらに、負荷が２次電池等の場合、２次電池がフル充電された時点で充電制御を施す必要がある。
【０００３】
すなわち非接触電力伝達には「電力供給側が単独の場合での、省エネ制御や金属異物過熱対策のための発振停止または抑制制御」と「正しい負荷が装着された場合での連続給電制御」と「負荷側からの要求に基づく電力伝達制御」の３つの制御が必要である。
【０００４】
【発明が解決しようとする課題】
上記３つの制御を全部あるいは一部満たす従来例が、いくつか提案されている。たとえば特開平６−３１１６５８号公報で開示された技術がある。これは独立した１対の信号用コイルを、電力供給側と負荷側との１対の電力用コイルとは別途に設け、負荷が装着されると１対の電力用コイルの誘導により負荷に電力が伝達される。そして、この電力を用いて負荷側の制御回路を駆動し、１対の信号用コイルによって制御信号を負荷側から電力供給側に戻して、電力供給側はこの制御信号に基づいて発振動作を制御するものである。
【０００５】
ところが、この構成は負荷検出および発振制御のための回路が別途必要であり、さらに信号周波数を電力送受のための周波数に対して識別しやすくするために、信号周波数を高くとる必要が生じて信号発生回路が複雑になり、またそれによるノイズ対策強化等でサイズアップやコストアップをもたらすという欠点がある。
【０００６】
また、特開平１１−１７８２４９号公報は自励発振の特性を生かし、正帰還ループを電力供給側内部から、一旦負荷側へ出し、再び電力供給側へ戻して、その帰還ループを負荷情報に利用するという極めてシンプルな回路で負荷の検出を行うことができ、省電力化および金属異物過熱防止を行うことができる回路である。さらに、電力周波数と信号周波数とが同一の周波数が使えるためにシンプルな構成で非接触電力伝達を行うことができる。しかし、制御信号が電力用周波数とおなじ周波数の正帰還フイードバック信号であるため、その信号振幅の増幅制御ができず、ノイズマージンが取りにくいという欠点がある。
【０００７】
本発明は、上記事由に鑑みてなされたものであり、その目的は、受電側の状況を識別して電力供給制御を行うことができて、シンプルな構造を有する非接触給電システムを提供することにある。
【０００８】
【課題を解決するための手段】
請求項１の発明は、高周波電力を出力する高周波インバータ回路と、前記高周波インバータ回路を制御するインバータ制御回路と、前記高周波インバータ回路から高周波電力を供給され、磁気結合による給電を行う第１のコイルと、入力信号コイルを有する信号受信回路とを備えて、前記入力信号コイルが検出した信号に基づいて前記インバータ制御回路が前記高周波インバータ回路を制御する非接触給電装置と、
第１のコイルに対向配置されて磁気結合による受電を行う第２のコイルと、第２のコイルの出力を所定の電気エネルギーに変換するための電力変換回路と、前記高周波インバータ回路の発振周波数の高調波成分の周波数を有する信号を発生する信号発生装置と、前記信号発生装置が発生する信号を制御する２次側制御回路と、前記電力変換回路から電気エネルギーを供給される負荷とを有する非接触受電装置とで構成され、
第１のコイルと第２のコイルとは互いに分離着脱自在なトランス構造を有し、前記入力信号コイルは、前記非接触受電装置の有無を検出した信号、及び前記信号発生装置が発生する信号を検出した信号を出力することを特徴とする。
【０００９】
請求項２の発明は、請求項１において、前記信号発生装置は、第３のコイルとコンデンサとからなり、前記高調波成分の周波数の共振周波数を有する共振回路であって、前記非接触給電装置に前記非接触受電装置が概略、対向配置された場合に、前記非接触給電装置及び非接触受電装置内の磁場、磁束、あるいは前記非接触受電装置内の電圧または電流情報から取り出した前記高調波成分の周波数の信号を発生させ、前記入力信号コイルは前記高調波成分の周波数の信号を検出し、前記インバータ制御回路は前記入力信号コイルが検出した信号に基づいて前記高周波インバータ回路を制御して、前記非接触給電装置から前記非接触受電装置への給電制御を行うことを特徴とする。
【００１０】
請求項３の発明は、請求項１または２において、前記高調波成分の周波数は、前記高周波インバータ回路の発振周波数の奇数倍の高調波成分の周波数であることを特徴とする。
【００１１】
請求項４の発明は、請求項３において、前記奇数倍の高調波成分は第３次高調波成分であることを特徴とする。
【００１２】
請求項５の発明は、請求項１乃至４いずれかにおいて、前記電力変換回路は、第２のコイルの出力を半波整流する回路を備えることを特徴とする。
【００１３】
請求項６の発明は、請求項１乃至５いずれかにおいて、前記信号受信回路は、前記入力信号コイルに接続した共振コンデンサを備え、前記高調波成分の周波数に共振することを特徴とする。
【００１４】
請求項７の発明は、請求項１乃至６いずれかにおいて、前記入力信号コイルは、差動接続した第４のコイルと第５のコイルとからなることを特徴とする。
【００１５】
請求項８の発明は、請求項１乃至７いずれかにおいて、前記非接触給電装置に前記非接触受電装置が概略、対向配置されて、前記非接触受電装置が給電を要求する場合に、前記信号発生装置の出力が大きくなることを特徴とする。
【００１６】
請求項９の発明は、請求項１乃至８いずれかにおいて、前記非接触給電装置に前記非接触受電装置が概略、対向配置されて、前記非接触受電装置が給電を拒否する場合に、前記２次側制御回路は前記信号発生装置の出力を低減させることを特徴とする。
【００１７】
請求項１０の発明は、請求項１乃至９いずれかにおいて、前記非接触給電装置が単独で存在する場合に、前記高周波インバータ回路は間欠発振を行うことを特徴とする。
【００１８】
請求項１１の発明は、請求項２乃至１０いずれかにおいて、前記高周波インバータ回路は、発振用スイッチング素子と、発振用スイッチング素子の制御端をグランドレベルに接続する自励制御用スイッチング素子とを備えて自励発振を行い、前記インバータ制御回路は、前記自励制御用スイッチング素子の発振を間欠に停止させることで前記発振用スイッチング素子の発振動作を間欠停止させる強制停止回路と、前記入力信号コイルの出力でオンすることにより前記強制停止回路の間欠停止動作を停止させる発振切替用スイッチング素子とを備え、
前記非接触給電装置が単独である場合、前記入力信号コイルの出力電圧は前記発振切替用スイッチング素子がオフとなる電圧に維持され、前記強制停止回路が動作して前記発振用スイッチング素子の発振動作を間欠発振に制御し、
前記非接触給電装置に前記非接触受電装置が概略、対向配置されて、前記非接触受電装置が給電を要求する場合、前記信号発生装置は、前記発振用スイッチング素子の発振動作が間欠発振である期間に発生した前記非接触給電装置及び非接触受電装置内の磁場、磁束、あるいは前記非接触受電装置内の電圧または電流情報から取り出した前記高調波成分の周波数の信号で第３のコイルを励磁し、第３のコイルと概略、対向配置されて、第３のコイルで発生した磁束を検出する前記入力信号コイルの出力電圧は前記発振切替用スイッチング素子がオンとなる電圧になり、前記強制停止回路が動作を停止して前記発振用スイッチング素子の発振動作を連続発振に制御し、
前記非接触給電装置に前記非接触受電装置が概略、対向配置されて、前記非接触受電装置が給電を拒否する場合、前記信号発生装置は、前記高調波成分の周波数の信号を低減させて第３のコイルの励磁を抑制し、前記入力信号コイルの出力電圧は前記発振切替用スイッチング素子がオフとなる電圧になり、前記強制停止回路が動作して前記発振用スイッチング素子の発振動作を間欠発振に制御することを特徴とする。
【００１９】
請求項１２の発明は、請求項２乃至１１いずれかにおいて、前記非接触受電装置は、第３のコイルとコンデンサとからなる共振回路の少なくとも一部を短絡または開放する補助スイッチング素子を備え、前記非接触給電装置に前記非接触受電装置が概略、対向配置されて、前記非接触受電装置が給電を拒否する場合に、前記２次側制御回路は、前記補助スイッチング素子を動作させて、前記信号発生装置の共振回路が発生する信号の周波数、振幅、波形のうち少なくとも１つを給電を必要とする場合の周波数、振幅、波形に対して変化させて、前記入力信号コイルは前記信号発生装置が発生した信号を検出し、前記インバータ制御回路は前記入力信号コイルが検出した信号に基づいて前記高周波インバータ回路を制御して、前記非接触給電装置から前記非接触受電装置への給電を低減させることを特徴とする。
【００２０】
請求項１３の発明は、請求項２乃至１１いずれかにおいて、前記非接触受電装置は、前記信号発生装置以外の内部回路の少なくとも一部を短絡または開放する補助スイッチング素子を備え、前記非接触給電装置に前記非接触受電装置が概略、対向配置されて、前記非接触受電装置が給電を拒否する場合に、前記２次側制御回路は、前記補助スイッチング素子を動作させて、前記信号発生装置の共振回路が発生する信号の周波数、振幅、波形のうち少なくとも１つを、給電を必要とする場合の周波数、振幅、波形に対して変化させて、前記入力信号コイルは前記信号発生装置が発生した信号を検出し、前記インバータ制御回路は前記入力信号コイルが検出した信号に基づいて前記高周波インバータ回路を制御して、前記非接触給電装置から前記非接触受電装置への給電を低減させることを特徴とする請求項２乃至１１いずれか記載の非接触給電システム。
【００２１】
請求項１４の発明は、請求項１３において、前記非接触受電装置は、第１のコイルが発生する磁束の少なくとも一部が鎖交する補助コイルと、前記補助コイルを短絡または開放する補助スイッチング素子とを備え、前記非接触給電装置に前記非接触受電装置が概略、対向配置されて、前記非接触受電装置が給電を拒否する場合に、前記２次側制御回路は、前記補助スイッチング素子を動作させて、前記信号発生装置の共振回路が発生する信号の周波数、振幅のうち少なくとも１つを給電を必要とする場合の周波数、振幅に対して小さくすることを特徴とする。
【００２２】
請求項１５の発明は、請求項１２において、前記信号発生装置は、第３のコイルとコンデンサとを並列接続した共振回路からなり、前記並列回路の両端間にダイオードと補助スイッチング素子との直列回路を備え、前記非接触給電装置に前記非接触受電装置が概略、対向配置されて、前記非接触受電装置が給電を拒否する場合は、前記２次側制御回路が前記補助スイッチング素子をオンさせて、第３のコイルの励磁を抑制することを特徴とする。
【００２３】
請求項１６の発明は、請求項１３において、前記非接触受電装置は、第２のコイルを短絡または開放する補助スイッチング素子を備え、前記非接触給電装置に前記非接触受電装置が概略、対向配置されて、前記非接触受電装置が給電を拒否する場合は、前記２次側制御回路は、前記補助スイッチング素子を動作させて、前記信号発生装置の共振回路が発生する信号の周波数、振幅のうち少なくとも１つを、給電を必要とする場合の周波数、振幅に対して小さくすることを特徴とする。
【００２４】
請求項１７の発明は、請求項１２乃至１６いずれかにおいて、前記補助スイッチング素子は一方向に導通する素子であることを特徴とする。
【００２５】
請求項１８の発明は、請求項１２乃至１７いずれかにおいて、前記補助スイッチング素子に直列接続したコンデンサを備えることを特徴とする。
【００２６】
請求項１９の発明は、請求項１２乃至１７いずれかにおいて、前記補助スイッチング素子に並列接続したコンデンサを備えることを特徴とする。
【００２７】
請求項２０の発明は、請求項１乃至１９いずれかにおいて、第２のコイルと第３のコイルとの磁気結合は疎結合であることを特徴とする。
【００２８】
請求項２１の発明は、請求項１乃至２０いずれかにおいて、前記入力信号コイルの出力部に、前記高調波成分の周波数と同じ周波数帯域を検出するフィルタを備えたことを特徴とする。
【００２９】
請求項２２の発明は、請求項１乃至２１いずれかにおいて、前記高周波インバータ回路は、第１のコイルの両端間に正弦波状の交番電圧を印加することを特徴とする。
【００３０】
請求項２３の発明は、請求項１乃至２２いずれかにおいて、前記高周波インバータ回路は、発振用スイッチング素子と、前記発振用スイッチング素子または第１のコイルに並列接続した共振コンデンサとを備えた一石の電圧共振インバータであることを特徴とする。
【００３１】
請求項２４の発明は、請求項７乃至２３いずれかにおいて、前記入力信号コイルを構成する差動接続した第４、第５のコイルと第１のコイルとの磁気結合は疎結合であり、第４のコイルと第５のコイルとのうちいずれか一方と第３のコイルとの磁気結合度は、第４のコイルと第５のコイルとのうちいずれか他方と第３のコイルとの磁気結合度より大きいことを特徴とする。
【００３２】
請求項２５の発明は、請求項２４において、第４，第５のコイルは第１のコイルに対し対称な位置に配置され、第３のコイルは、第４のコイルと第５のコイルとのうちいずれか一方に対向して配置されることを特徴とする。
【００３３】
請求項２６の発明は、請求項１において、非接触給電装置から非接触受電装置への給電が行われているとき、第２のコイルの両端電圧、コイル電流は歪んだ波形となり、前記信号発生装置は、第２のコイルの両端電圧、コイル電流に含まれる高調波成分を発生源とした信号を発生することを特徴とする。
【００３４】
請求項２７の発明は、請求項２６において、前記入力信号コイルを構成する差動接続した第４、第５のコイルと第１のコイルとの磁気結合は疎結合であり、第４のコイルと第５のコイルとのうちいずれか一方と第２のコイルとの磁気結合度は、第４のコイルと第５のコイルとのうちいずれか他方と第２のコイルとの磁気結合度より大きいことを特徴とする。
【００３５】
請求項２８の発明は、請求項１乃至２７いずれかにおいて、前記信号発生装置は、前記高調波成分の周波数の共振周波数を有する第３のコイルとコンデンサとの共振回路による信号発生手段と、第２のコイルの両端電圧、コイル電流に含まれる高調波成分を発生源とした信号を発生する信号発生手段とを備えることを特徴とする。
【００３６】
請求項２９の発明は、請求項１乃至２５，２８いずれかにおいて、前記信号発生装置は、第３のコイルに直列接続したインダクタを備えることを特徴とする。
【００３７】
【発明の実施の形態】
以下、本発明の実施の形態を図面に基づいて説明する。
【００３８】
（実施形態１）
本実施形態の非接触給電システムのブロック構成図を図１に示す。非接触給電システムは、電力供給を行う非接触給電装置１と、電力を供給される負荷を含む非接触受電装置２とからなり、非接触給電装置１は、高周波電力を出力する高周波インバータ回路１１と、高周波インバータ回路１１を制御するインバータ制御回路１３と、高周波インバータ回路１１から高周波電力を供給され、磁気結合による給電を行う第１のコイルＬ１と、互いに極性を反対にして直列に差動接続した第４のコイルＬ４、第５のコイルＬ５からなる入力信号用コイルＬｓと、第４のコイルＬ４、第５のコイルＬ５の差動接続回路の出力を増幅するために差動接続回路の両端間に接続した共振コンデンサＣ４とを備え、第４のコイルＬ４、第５のコイルＬ５、及び共振コンデンサＣ４は差動共振回路として動作する信号受信回路１２を構成している。
【００３９】
非接触受電装置２は、負荷３０を有しており、第１のコイルＬ１に対向配置されて磁気結合による受電を行う第２のコイルＬ２と、第２のコイルＬ２の出力を負荷３０へ供給するのに適した出力に変換するための電力変換回路２１と、信号受信回路１２の入力信号用コイルＬｓに対向配置された第３のコイルＬ３と、第３のコイルＬ３の両端間に接続した共振コンデンサＣ８と、共振コンデンサＣ５の両端間に接続したスイッチＳ２と、スイッチＳ２のオン・オフを制御する信号を出力する２次側制御回路２３とを備え、第３のコイルＬ３と共振コンデンサＣ８との共振回路は非接触受電装置２からの信号を出力する信号発生装置２４を構成している。
【００４０】
上記のような非接触給電システムは、第１のコイルＬ１と第２のコイルＬ２とが分離着脱自在なトランス構造となっており、高周波インバータ回路１１から高周波電力を供給された第１のコイルＬ１が発生する磁束によって、第２のコイルＬ２には誘起電圧を発生させ、その誘起電圧を電力変換回路２１で所定の形態に変換して負荷３０に出力している。そして、信号発生装置２４は高周波インバータ回路１１の発振周波数の高調波と同じ周波数を有する信号を発生し、入力信号コイルＬｓがこの信号を検出して、インバータ制御回路１３はこの検出信号に基づいて高周波インバータ回路１１の発振を制御している。
【００４１】
ここで、第１のコイルＬ１と入力信号コイルＬｓとは磁気的に疎結合となるように配置され、また第４のコイルＬ４と第５のコイルＬ５とも磁気的に疎結合となるように配置されている。そして、１次側の第４のコイルＬ４に対向して、２次側には第３のコイルＬ３が配置されている。磁気的に疎結合であるとは、一方のコイルが作る磁束の全てが他方のコイルに鎖交しない状態であり、例え、磁性体のコアがコイルの軸上にあっても、各コイルを完全に密着して重ねずに軸方向または半径方向に離して配置すれば疎結合になる。
【００４２】
次に図２に示す具体的な回路構成を用いて、各部の構成について詳細に説明する。まず、非接触給電装置１の高周波インバータ回路１１は、自励発振回路であり、直流電源Ｅ１とスイッチＳ１との直列回路に並列接続した抵抗Ｒ２とコンデンサＣ１との直列回路と、共振コンデンサＣ２と発振用のスイッチング素子ＦＥＴ１と抵抗Ｒ１との直列回路と備えており、共振コンデンサＣ２には第１のコイルＬ１が並列接続している。抵抗Ｒ２とコンデンサＣ１との接続中点−スイッチング素子ＦＥＴ１のゲート間には、第１のコイルと図示の極性で密結合している帰還コイルＬ６が接続している。帰還コイルＬ６を介してコンデンサＣ１に並列に接続している自励発振制御用のスイッチング素子Ｔｒ１は、スイッチング素子ＦＥＴ１の発振を制御する素子である。また、スイッチング素子ＦＥＴ１のソース−スイッチング素子Ｔｒ１のベース間には抵抗Ｒ３が接続し、スイッチング素子Ｔｒ１のベース−エミッタ間にはコンデンサＣ３が接続している。
【００４３】
信号受信回路１２の構成は図１と同様であり、一方の出力端は、高周波インバータ回路のグランド（直流電源Ｅ１の低電圧出力側）に接続している。
【００４４】
インバータ制御回路１３は、高周波インバータ回路１１の自励発振制御用のスイッチング素子Ｔｒ１をオン・オフして、高周波インバータ回路１１の発振を連続発振と間欠発振との２通りに制御している回路で、信号受信回路１２の他方の出力端に一端を接続したダイオードＤ３とツェナダイオードＺＤ１と抵抗Ｒ７との直列回路の他端は発振切替用のスイッチング素子Ｔｒ２のベースに接続している。信号受信回路１２の出力端間にはダイオードＤ３を介してコンデンサＣ５が接続し、スイッチング素子Ｔｒ２のベース−エミッタ間には抵抗Ｒ８が接続している。スイッチング素子ＦＥＴ１のドレインは、抵抗Ｒ４，Ｒ５の直列回路を介してグランドレベルに接続しており、コンデンサＣ６はダイオードＤ２を介して抵抗Ｒ５に並列接続している。ダイオードＤ２とコンデンサＣ６との接続中点は、ダイオードＤ１と抵抗Ｒ３とを介して自励発振制御用のスイッチング素子Ｔｒ１のベースに接続しており、さらに抵抗Ｒ６を介してトランジスタＴｒ２のコレクタに接続している。ここで、抵抗Ｒ４，Ｒ５、ダイオードＤ１，Ｄ２、及びコンデンサＣ６は、スイッチング素子ＦＥＴ１の発振動作を間欠停止させる強制停止回路１５を構成している。
【００４５】
非接触受電装置２の２次側回路２１は、第２のコイルＬ２の出力端間に接続したコンデンサＣ７と、第２のコイルＬ２の一方の出力端に直列接続した整流用のダイオードＤ４とを備えて、第２のコイルＬ２の誘起電圧を半波整流した出力を負荷である２次電池２２に供給しており、２次電池２２の両端は２次側制御回路２３に接続している。
【００４６】
第３のコイルＬ３の両端間には、共振コンデンサＣ８と、ダイオードＤ５及び補助スイッチング素子Ｔｒ３の直列回路とを接続し、補助スイッチング素子Ｔｒ３のベースは２次側制御回路２３に接続している。
【００４７】
次に、スイッチＳ１がオンになった時点からの発振開始から連続発振に至る過程を、図３に示す波形図を用いて説明する。まず、スイッチＳ１がオンすると、電圧Ｖｅ１を発生する直流電源Ｅ１は抵抗Ｒ２を介してコンデンサＣ１を充電する。このとき第１のコイルＬ１と密結合している帰還コイルＬ６には、誘起電圧が発生していないため、スイッチング素子ＦＥＴ１のゲート電圧ＶｇはコンデンサＣ１の電圧Ｖｃ１に等しい。ゲート電圧Ｖｇが次第に上昇し、スイッチング素子ＦＥＴ１をオンできる電圧Ｖｇｏｎに達するとスイッチング素子ＦＥＴ１はオンになり、ドレイン電圧Ｖｄは、ほぼゼロ電位になる。この時、第１のコイルＬ１と並列接続された共振コンデンサＣ２の両端の共振電圧Ｖｃ２は直流電源Ｅ１の電源電圧Ｖｅ１でチャージされて、第１のコイルＬ１には、ほぼ単調に増加するコイル電流ＩＬ１が流れ始める。
【００４８】
コイル電流ＩＬ１が流れ始めると、第２のコイルＬ２にはトランスの作用によって誘起電圧が発生する。同様に第１のコイルＬ１と密結合している帰還コイルＬ６にも誘起電圧Ｖｆ１が発生する。すると、グランドレベルからみたゲート電圧Ｖｇは、Ｖｃ１＋Ｖｆ１となり、急速にスイッチング素子ＦＥＴ１は安定したオン状態となる。
【００４９】
またコイル電流ＩＬ１は、スイッチング素子ＦＥＴ１を通じて抵抗Ｒ１に流れるドレイン電流Ｉｄとほぼ等しく、時間とともに抵抗Ｒ１の電圧Ｖｔｒ１が増加する。電圧Ｖｔｒ１が、スイッチング素子Ｔｒ１のオンが可能な電圧に達すると、スイッチング素子Ｔｒ１はオンし始める。スイッチング素子Ｔｒ１がオンし始めると、スイッチング素子ＦＥＴ１のゲート入力容量、及び帰還コイルＬ６を介したコンデンサＣ１の容量に蓄積されていた電荷を引き抜きはじめ、電圧Ｖｃ１、ゲート電圧Ｖｇは低下し始める。ゲート電圧Ｖｇの低下が進むと、スイッチング素子ＦＥＴ１はオフ状態への移行を開始し、オン抵抗が増加してドレイン電圧Ｖｄは次第に増加していく。
【００５０】
ドレイン電圧Ｖｄの増加に応じて、共振電圧Ｖｃ２も減少し始め、そして帰還コイルＬ６の誘起電圧Ｖｆ１も減少し始めるためゲート電圧Ｖｇはさらに加速して低下する。この結果、急速にスイッチング素子ＦＥＴ１はオフ状態に移行し、電圧Ｖｔｒ１も減少してスイッチング素子Ｔｒ１は再びオフになる。
【００５１】
また共振電圧Ｖｃ２は、共振コンデンサＣ２と第１のコイルＬ１との共振作用により正弦波状の電圧となり、コイル電流ＩＬ１も正弦波状になる。この間、直流電源Ｅ１から抵抗Ｒ２を介してコンデンサＣ１への充電電流は常に流れており、電圧Ｖｃ１を再び増加させる。
【００５２】
共振電圧Ｖｃ２が1サイクルの終了間近になると、ドレイン電圧Ｖｄはグランドレベルに近づき、そのときの帰還コイルＬ６の起電力Ｖｆ１と電圧Ｖｃ１との和のゲート電圧Ｖｇが、再びスイッチング素子ＦＥＴ１をオンさせる。以降は、前記動作の繰り返しにより発振が継続する。この一連の動作は、非接触受電装置２が非接触給電装置１に対向配置されてない状態、すなわち非接触給電装置１が単独の場合でも、第２のコイルに起電力を生じないこと以外は同様の動作となる。
【００５３】
しかし、非接触給電装置１が単独の場合には、省エネルギーや金属異物の過熱保護のために高周波インバータ回路１１の発振を停止または抑制する必要がある。本実施形態では高周波インバータ回路１１の発振を強制停止回路１５によって間欠発振とすることでこの役割を果たしている。
【００５４】
以下、図４に示す各部の波形図により間欠発振動作の制御について説明する。まず、スイッチＳ１を投入して連続発振が開始するまでは、前記図３での説明と同様である。図２のインバータ制御回路１３は、ドレイン電圧Ｖｄを抵抗Ｒ４，Ｒ５で抵抗分圧し、ダイオードＤ２を介してコンデンサＣ６に電荷を蓄積していく積分回路を有している。コンデンサＣ６の電圧はダイオードＤ１を介してトランジスタＴｒ１のベース抵抗Ｒ３に接続しており、コンデンサＣ６の電圧が、スイッチング素子Ｔｒ１をオンさせることができる入力電圧値とダイオードＤ１、抵抗Ｒ３の各電圧降下との和を超えると、スイッチング素子Ｔｒ１がオン状態になる。
【００５５】
スイッチング素子Ｔｒ１がオン状態になると、スイッチング素子ＦＥＴ１のゲート入力容量、及び帰還コイルＬ６を介したコンデンサＣ１の容量に蓄積されていた電荷を引き抜く。この時スイッチング素子Ｔｒ１のオン時間が長く保持されると、電圧Ｖｃ１が、定常発振状態での電圧よりもさらに低下し、直流電源Ｅ１から抵抗Ｒ２を介してコンデンサＣ１へ流れる充電電流による電圧回復が定常状態の電圧まで達せず、スイッチング素子ＦＥＴ１はオフ状態を継続することになる。
【００５６】
したがって、直流電源Ｅ１から抵抗Ｒ２を介してコンデンサＣ１へ流れる充電電流のみによる電圧Ｖｃ１がスイッチング素子ＦＥＴ１をオンできる入力電圧に達するまで次の発振起動は行われない。すなわちこの動作の繰り返しで安定した間欠発振となる。
【００５７】
この間欠発振をさせるために重要なことは、まず、高周波インバータ回路１１を発振させてから、時間遅延をさせて停止する機能を持っていなければならないことである。理由は高周波インバータ回路１１が発振する前にスイッチング素子Ｔｒ１がオンになったとすると、永久に発振が停止した状態になるからである。図２の回路での発振停止状態は、ドレイン電圧Ｖｄの電位が電源電圧Ｖｅ１になるため、抵抗Ｒ４，Ｒ５の分圧比を、この発振停止状態ではスイッチング素子Ｔｒ１がオンしない値にしておく必要がある。そして発振が開始してからスイッチング素子Ｔｒ１がオンできるレベルに達するようにするには、発振によってドレイン電圧Ｖｄが電源電圧Ｖｅ１よりも大きくなったときの電圧を利用して、コンデンサＣ６を徐々に充電していき、適当な時間経過の後、スイッチング素子Ｔｒ１がオンできるように抵抗Ｒ４，Ｒ５の分圧比を設定しておけばよい。上記のように構成することで、図２に示す高周波インバータ回路１１とインバータ制御回路１３は、非接触給電装置１が単独の場合には、間欠発振を行うことができる。
【００５８】
ところで、非接触給電装置１に非接触受電装置２が概略、対向配置されて電力伝達を行わせる必要がある場合には、この間欠発振を確実に停止させる機能が必要となる。間欠発振を確実に停止させる、すなわち連続発振をさせる機能を果たすために、非接触給電装置１から見て正しい負荷であるかどうかを判定する機能が必要であり、この確実な判定を行うために非接触受電装置２から非接触給電装置１に所定の信号を送る方法が考えられ、そこで非接触受電装置２側には高調波共振回路を用いた信号発生装置２４が必要となる。以下、この動作について説明する。
【００５９】
非接触給電装置１では、共振コンデンサＣ４によって増幅された第４，第５のコイルの差動回路の出力は、ダイオードＤ３で整流されて、コンデンサＣ５に充電される。そして、コンデンサＣ５の充電電圧が、スイッチング素子Ｔｒ２をオンさせることができる入力電圧値とツェナダイオードＺＤ１のツェナ電圧と抵抗Ｒ７の電圧降下との和を超えると、スイッチング素子Ｔｒ２がオン状態になり、抵抗Ｒ６を介して接続しているコンデンサＣ６の電荷を引き抜く。すると、コンデンサＣ６の積分動作でトランジスタＴｒ１をオンにすることはできず、スイッチング素子ＦＥＴ１の間欠発振を停止して、連続発振にすることができる。
【００６０】
したがって、非接触給電装置１に非接触受電装置２が概略、対向配置されて電力伝達を行わせる必要がある場合には、非接触給電装置１に非接触受電装置２が概略、対向配置されたことを、非接触受電装置２側で検知して、その検知したことを非接触給電装置１に固有の信号で伝えて、連続発振させればよい。
【００６１】
ここで、信号発生装置２４を、使用する分離着脱式トランスの構造や仕様において高周波インバータ回路１１の発振周波数の３倍の周波数（第３次高調波成分）に共振するように第３のコイルＬ３と共振コンデンサＣ８とを設定しておけば、第１のコイルＬ１が発生した磁束を信号発生装置２４の第３のコイルＬ３が検出したときに、この磁束を励振源として、第３のコイルＬ３と共振コンデンサＣ８との高調波共振回路によって、信号発生装置２４の出力振幅を大きくできる。そして、第３のコイルＬ３は第３次高調波成分の周波数の共振電流によって励磁され、この磁束を入力信号コイルＬｓが検知して、大きな出力電圧を発生させて発振切替用のスイッチング素子Ｔｒ２をオンさせることで、高周波インバータ回路１１を連続発振させることができる。
【００６２】
そして、第４のコイルＬ４、第５のコイルＬ５、及び共振コンデンサＣ４からなる差動共振回路として動作する信号受信回路１２を、信号発生装置２４で設定したのと同様に第３次高調波成分の周波数に共振して、出力振幅が大きくなるように設定すればより確実な信号検出を行うことができる。
【００６３】
この信号検出動作の具体的な動作について以下、説明する。非接触給電装置１が単独の場合は、信号受信回路１２の入力信号コイルＬｓは１次側の磁束や磁場の情報を検出する。高周波インバータ回路１１が電圧共振型のインバータ回路であれば、第１のコイルＬ１の電圧や電流は、略正弦波状をしている。したがって、第３次高調波成分は小さく、信号受信回路１２はゼロ、または低い電圧を出力する。もし、第３次高調波成分が大きい場合には、信号受信回路１２で出力電圧が小さくなるように設定しておけばよい。したがって、スイッチング素子Ｔｒ２はオフのままであり、高周波インバータ回路１１は間欠発振を継続する。
【００６４】
次に、非接触受電装置２が非接触給電装置１に概略、対向配置されて給電を必要とする場合には、間欠発振の発振期間に第１のコイルＬ１で発生した磁束が信号発生装置２４の第３のコイルＬ３にも鎖交し、鎖交した交番磁束は高周波インバータ回路１１の発振周波数を有する誘起電圧を第３のコイルＬ３に発生して、その誘起電圧によって第３のコイルＬ３と共振コンデンサＣ８とが直列共振動作を行う。このときの直列共振周波数は、発振周波数（基本波）の３倍、すなわち第３次高調波成分の周波数に設定しているため、第３のコイルＬ３には第３次高調波成分の周波数の交流電圧が大きく発生し、第３次高調波成分の周波数の交流電流を第３のコイルＬ３に流す。
【００６５】
したがって、第３のコイルＬ３に対向して配置された第４のコイルＬ４には第３次高調波成分の周波数の交流電圧が誘起し、信号受信回路１２は、第３次高調波成分の周波数を有する大きな振幅の電圧を出力し、ダイオードＤ３，コンデンサＣ５で整流，平滑した電圧はスイッチング素子Ｔｒ２をオンして、高周波インバータ回路１１を間欠発振から連続発振動作に切替える。
【００６６】
さらに、非接触受電装置２が非接触給電装置１に概略、対向配置されて給電を停止する必要がある場合には、２次側制御回路２３によって補助スイッチング素子Ｔｒ３をオンして、ダイオードＤ５を介して信号発生装置２４の両端を短絡すれば、高調波共振機能を失って、第３のコイルＬ３の両端に発生する第３次高調波成分の周波数の電圧がゼロまたは低減し、信号受信回路１２の出力もゼロ、または低い電圧となって、ダイオードＤ３，コンデンサＣ５で整流，平滑した電圧はスイッチング素子Ｔｒ２をオフさせて、高周波インバータ回路１１は間欠発振となる。この補助スイッチング素子Ｔｒ３による短絡は完全に行う必要はなく、周期的に短絡させても十分効果はある。また、信号発生装置２４の両端を短絡せずに、信号発生装置２４の回路の一部を開放して電流が流れなくすることも高調波共振機能を低減あるいは無くす方法の１つである。本実施形態では、ダイオードＤ５を介して補助スイッチング素子Ｔｒ３によって短絡しているので、交流の１方向のみを短絡しているが、このような１方向のみの短絡でも第３次高調波成分の低減効果は十分である。
【００６７】
次に、図５は、非接触給電装置１に非接触受電装置２が概略、対向配置された構造の側面断面図を示しており、分離着脱自在なトランス構造をなしている。この分離着脱式トランスは、磁気抵抗を小さくするために断面コの字型の磁性体からなる第１，第２のコア１４，２５を備えており、第１のコイルＬ１は第１のコア１４の両端に設けた突部１４ａ，１４ｂ間に巻回され、第３、第４のコイルＬ３，Ｌ４は第１のコイルＬ１を軸方向に挟んで（第１のコイルＬ１の軸方向に対称に）、突部１４ａ，１４ｂ間に巻回され、帰還コイルＬ６は第１のコイルＬ１と第５のコイルＬ５とに軸方向に挟まれて突部１４ａ，１４ｂ間に巻回されている。第２のコイルＬ２は第２のコア２５の両端に設けた突部２５ａ，２５ｂ間に巻回され、第３のコイルＬ３は突部２５ａ，２５ｂ間の第４のコイルＬ４に対向する箇所に第２のコイルＬ２とは軸方向に分離して巻回されている。
【００６８】
上記のように、自励発振用の帰還コイルＬ６は、第１のコイルＬ１が発生する磁束が鎖交するように第１のコイルＬ１の近傍に配置され、入力信号用コイルＬｓを構成する第４，第５のコイルＬ４，Ｌ５は、第１のコイルＬ１が発生する磁束に対して比較的疎結合になるように、第１のコイルＬ１から離れて配置されている。
【００６９】
ここでのポイントは、第４，第５のコイルＬ４，Ｌ５は第１のコイルＬ１に対して磁気的に強く結合しないように配置されることである。その理由は、第４のコイルＬ４が第３のコイルＬ３から受けた信号を有効として、大きく出力しなければならないからであり、もし第４，第５のコイルＬ４，Ｌ５と第１のコイルＬ１とが磁気的に密結合であるならば、第３のコイルＬ３が発生する磁束信号を受けても、第４，第５のコイルＬ４，Ｌ５の出力変化の大部分は、第１のコイルＬ１が発生する磁束変化に支配されてしまうからである。
【００７０】
また、第４，第５のコイルＬ４，Ｌ５は差動接続されており、第４のコイルＬ４での検出電圧の変化と第５のコイルＬ５での検出電圧の変化との差を出力して、出力の増幅効果を大きくみせたものである。つまり、第４，第５のコイルＬ４，Ｌ５の各誘起電圧が同じように変化しては効果が無く、一方のコイルのみの検出電圧の変化が必要である。したがって、差動接続された第４，第５のコイルＬ４，Ｌ５は、第３のコイルＬ３に対して磁気的に結合度の差を設ければよく、第４，第５のコイルＬ４，Ｌ５のうちいずれか一方のコイルと第３のコイルＬ３との磁気結合が密になるように互いに近くに配置し、他方のコイルと第３のコイルＬ３との磁気結合は疎になるように配置すればよい。本実施形態では、第４のコイルＬ４と第３のコイルＬ３との磁気結合が密になっており、第３のコイルＬ３は第４のコイルＬ４に対向する箇所に配置されている。
【００７１】
このときの第３のコイルＬ３が発生する磁束１００は、第４のコイルＬ４に多くが鎖交し、第５のコイルＬ５に鎖交するものは少ない。実際には、第３のコイルＬ３が発生する磁束１００は、第１のコイルＬ１が発生する磁束や第２のコイルＬ２に流れる電流によって発生する磁束に重畳されることになるが、前記各コイルの磁気的結合の関係によって、第１のコイルＬ１，Ｌ２が発生する磁束の影響は、差動接続した第４，第５のコイルＬ４，Ｌ５の各出力がお互いに打ち消し合う関係になって、入力信号コイルＬｓからは出力されない。
【００７２】
しかし、第３のコイルＬ３が発生する磁束の変化は、第４のコイルＬ４のみに多く鎖交して、入力信号コイルＬｓから大きな出力を生じさせることができる。しかも、本実施形態では、第３のコイルＬ３が発生する磁束は、高周波インバータ回路１１の発振周波数ではなく、第３次高調波成分の周波数であるため、第１のコイルＬ１の電流の影響や、他のコイルの電流の影響をさらに低減することができる。
【００７３】
また、第３のコイルＬ３は第２のコイルＬ２の電流による磁束の影響を受けやすいが、第２のコイルＬ２と第３のコイルＬ３とを疎結合とすることによって、第２のコイルＬ２の電流による影響を受けずに、高調波成分の周波数の磁束のみを発生することができる。
【００７４】
次に、図６は、非接触給電装置１が単独の場合の分離着脱式トランスの１次側の側面断面図を示しており、第１のコイルＬ１は磁束１０１を発生している。ここで重要なことは、第１のコイルＬ１を挟んで軸方向に対称に第４，第５のコイルＬ４，Ｌ５が離れて巻回されているので、第１のコイルＬ１のコイル電流ＩＬ１が発生する磁束１０１による鎖交磁束の変化は、第４，第５のコイルＬ４，Ｌ５ともに同じであり、差動出力はゼロまたは小さい値にすることができる。
【００７５】
なお、本実施形態においては、信号発生装置２４が、高周波インバータ回路１１の発振周波数の第３次高調波の周波数の磁束を発生しているが、歪を有する波形は基本波に対して整数倍の高調波を含有しており、いずれの高調波を利用しても同様の効果を得ることができる。特に本実施形態のように波形が交流に近く、直流成分が小さい場合は奇数倍の高調波が支配的であり、これらの奇数倍の高調波を利用することができる。
【００７６】
ところで、非接触給電装置１に非接触受電装置２が概略、対向配置された場合で、給電を拒否する場合に、図２に示す非接触給電システムでは信号発生装置２４を直接制御して高周波インバータ回路１１を間欠発振としているが、図７に示す非接触給電システムのように第２のコイルＬ２の出力端間にダイオードＤ８と補助スイッチング素子Ｔｒ５との直列回路を接続し、２次側制御回路２３からの信号で補助スイッチング素子Ｔｒ５をオンすることで第２のコイルＬ２の出力端間を短絡しても高周波インバータ回路１１を間欠発振とすることができる。また図８に示す非接触給電システムのように非接触受電装置２に補助コイルＬ７と補助コイルＬ７の両端間に接続した補助スイッチング素子Ｔｒ６とを設けて、２次側制御回路２３からの信号で補助スイッチング素子Ｔｒ６をオンすることで補助コイルＬ７の出力端間を短絡しても高周波インバータ回路１１を間欠発振とすることができる。これは、第２のコイルＬ２や補助コイルＬ７を短絡することで第１のコイルＬ１が発生する磁束を打ち消すように働いて磁束を弱める効果があるため、励振源として第３のコイルＬ３に鎖交する第１のコイルＬ１の磁束が弱くなることで信号発生装置２４の出力を小さくできるものである。
【００７７】
また、図９に示すように、第３のコイルＬ３の両端間に、補助スイッチＳ３とコンデンサＣ１０との直列回路を接続しても、信号発生装置２４の出力を制御できる。これは、補助スイッチＳ３がオンすることでコンデンサＣ１０が共振コンデンサＣ８に並列に接続されて、高調波共振周波数を大きく変化させることができ、信号受信回路１２で設定している共振周波数からずれることで、信号受信回路１２の出力が変化するものである。同様に他のコイルを制御するスイッチング素子に直列あるいは並列にコンデンサを設けて制御しても信号発生装置２４の出力を制御できる。
【００７８】
このように本実施形態の非接触給電システムは、電力の周波数の高調波周波数と同じ周波数の信号を用いて給電状況を識別して電力供給制御を行うことで、回路構成やトランス構造がシンプルになって、全体のシステムのサイズの小型化とコストダウンとを図ることができる。
【００７９】
なお、図１，図７〜９に示す非接触給電システムでは、信号受信回路１２に第３，４のコイルＬ３，Ｌ４と共振コンデンサＣ４との差動共振回路を用いているが、本願発明の特徴は、信号発生装置２４によって特定の高調波周波数の磁束を発生させて、信号受信回路１２がこの磁束を検知するものであるから、信号受信回路１２は入力信号用コイルＬｓで検出した信号から特定の高調波周波数の信号を分離するフィルタ機能があればよい。
【００８０】
（実施形態２）
実施形態１では負荷が２次電池２２のような定電圧負荷であるが、負荷には定電圧負荷や抵抗負荷等いろいろある。また、交流を直流に変換して負荷に供給するために整流回路や平滑回路は必要であり、実施形態１では２次側の回路は半波整流回路で構成されている。この整流、平滑方式や負荷の種類は非接触給電システムの応用目的で決まり、電動歯ブラシや電気シェーバ等の携帯用電子機器では負荷として２次電池を用い、整流回路としては低コストである半波整流回路をよく用いる。このような２次側回路や負荷を持つ場合には、非接触受電装置２内に信号発生装置２４のような高調波周波数の磁束を発生させる回路を設けなくても、例えば第２のコイルＬ２の電流の波形に高調波成分が多く含まれておれば、その情報を入力信号コイルＬｓで検出させればよい。図１０は実施形態１における第２のコイルＬ２の両端電圧Ｖｌ２波形であり、半波整流用のダイオードＤ４が導通している期間の電圧Ｖ１０は２次電池２２とダイオードＤ４の電圧降下との和に略等しい。
【００８１】
また、第１のコイルＬ１と第２のコイルＬ２とは疎結合となっているので、図１１の２次側回路の等価回路に示すように、２次側換算の漏れインダクタンスＬａが無視できず、第２のコイルＬ２に誘導された電圧源ＡＣ１は直列に挿入されたインダクタンスＬａを介して、ダイオードＤ４、２次電池２２の直列回路に接続される。このような回路では誘導された電圧源ＡＣ１が正弦波であっても、第２のコイルＬ２の両端電圧は図１０のように正弦波とはかけ離れた波形となり、さらに周期Ｔ０は正弦波状に変化している期間Ｔ１の約３倍になっている。このことは、電圧Ｖｌ２が基本波の３倍の高調波成分（第３次高調波）を多く含んでいることを示している。
【００８２】
第２のコイルＬ２の電圧波形が図１０のようであれば、第２のコイルＬ２のコイル電流により発生する磁束成分は分離着脱自在なトランス部全体に強い影響を与えるため、信号受信回路１２が第３次高調波の周波数を選択して増幅すれば、非接触給電装置１に非接触受電装置２が概略、対向配置されるだけで高周波インバータ回路１１の動作を間欠発振から連続発振に切替えることができる。このとき、実施形態１同様に、高周波インバータ回路１１の発振周波数の３倍の周波数（第３次高調波成分）に共振するように第３のコイルＬ３と共振コンデンサＣ８とを設定した信号発生装置２４を組み合わせれば、より効果的となる。なお、図１０に示す第２のコイルＬ２の電圧波形Ｖｌ２は、整流条件や負荷条件等により変化するので、第３次高調波に限らずその時の電圧波形に最も多く含まれる高調波を利用すればよい。
【００８３】
次に、図１２に第２のコイルＬ２の電圧・電流波形から高調波成分を有効に取り出す分離着脱自在なトランス構造の側面断面図を示し、この分離着脱式トランスは、磁気抵抗を小さくするために断面コの字型の磁性体からなる第１，第２のコア１４，２５を備えており、第１のコイルＬ１は第１のコア１４の両端に設けた突部１４ａ，１４ｂ間に巻回され、第３、第４のコイルＬ３，Ｌ４は第１のコイルＬ１を軸方向に挟んで（第１のコイルＬ１の軸方向に対称に）、突部１４ａ，１４ｂ間に巻回され、帰還コイルＬ６は第１のコイルＬ１と第５のコイルＬ５とに軸方向に挟まれて突部１４ａ，１４ｂ間に巻回されている。第２のコイルＬ２は第２のコア２５の両端に設けた突部２５ａ，２５ｂ間に突部２５ａ側に偏倚して巻回されている。
【００８４】
ここでのポイントは、差動接続した第４，第５のコイルＬ４，Ｌ５を第１のコイルＬ１と磁気的に疎結合とし、第２のコイルＬ２と第４のコイルＬ４との磁気結合度が、第２のコイルＬ２と第５のコイルＬ５との磁気結合度よりも大きくなるように構成したことである。
【００８５】
（実施形態３）
図１３に示す本実施形態の非接触給電システムは、実施形態１の図２に示す非接触給電システムと略同様であるが、信号発生装置２４の構成が異なり、第３のコイルＬ３に直列にチョークコイルＬ７を接続し、第３のコイルＬ３とチョークコイルＬ７との直列回路に共振コンデンサＣ８を並列接続した構成となっている。
【００８６】
このような本実施形態では、第３のコイルＬ３に直列にチョークコイルＬ７を接続したことでインダクタンス値を大きくしたもので、スペースの関係等で第３のコイルＬ３の巻数を大きくできないときは、インダクタンス値が小さいために共振電流が大きくなりすぎて損失熱が無視できなくなる場合がある。このようなときには、第３のコイルＬ３に、大きなインダクタンス値を有するチョークコイルＬ７を直列接続して共振回路を構成すれば、共振電流を低減することができる。
【００８７】
なお、実施形態１，２，３は、「電力供給側が単独の場合での、省エネ制御や金属異物過熱対策のための発振停止または抑制制御」と「正しい負荷が装着された場合での連続給電制御」と「負荷側からの要求に基づく電力伝達制御」の３つの制御を対象にしているが、「電力供給側が単独の場合での、省エネ制御や金属異物過熱対策のための発振停止または抑制制御」と「正しい負荷が装着された場合での連続給電制御」の２つの制御のみを対象にした場合にも適用できる。
【００８８】
【発明の効果】
請求項１の発明は、高周波電力を出力する高周波インバータ回路と、前記高周波インバータ回路を制御するインバータ制御回路と、前記高周波インバータ回路から高周波電力を供給され、磁気結合による給電を行う第１のコイルと、入力信号コイルを有する信号受信回路とを備えて、前記入力信号コイルが検出した信号に基づいて前記インバータ制御回路が前記高周波インバータ回路を制御する非接触給電装置と、
第１のコイルに対向配置されて磁気結合による受電を行う第２のコイルと、第２のコイルの出力を所定の電気エネルギーに変換するための電力変換回路と、前記高周波インバータ回路の発振周波数の高調波成分の周波数を有する信号を発生する信号発生装置と、前記信号発生装置が発生する信号を制御する２次側制御回路と、前記電力変換回路から電気エネルギーを供給される負荷とを有する非接触受電装置とで構成され、
第１のコイルと第２のコイルとは互いに分離着脱自在なトランス構造を有し、前記入力信号コイルは、前記非接触受電装置の有無を検出した信号、及び前記信号発生装置が発生する信号を検出した信号を出力するので、電力の周波数の高調波周波数と同じ周波数の信号を用いて給電状況を識別して電力供給制御を行うことで、回路構成やトランス構造がシンプルになって、全体のシステムのサイズの小型化とコストダウンとを図ることができる。したがって受電側の状況を識別して電力供給制御を行うことができ、且つシンプルな構造を有する非接触電力伝達装置を提供することができるという効果がある。
【００８９】
請求項２の発明は、請求項１において、前記信号発生装置は、第３のコイルとコンデンサとからなり、前記高調波成分の周波数の共振周波数を有する共振回路であって、前記非接触給電装置に前記非接触受電装置が概略、対向配置された場合に、前記非接触給電装置及び非接触受電装置内の磁場、磁束、あるいは前記非接触受電装置内の電圧または電流情報から取り出した前記高調波成分の周波数の信号を発生させ、前記入力信号コイルは前記高調波成分の周波数の信号を検出し、前記インバータ制御回路は前記入力信号コイルが検出した信号に基づいて前記高周波インバータ回路を制御して、前記非接触給電装置から前記非接触受電装置への給電制御を行うので、信号発生装置に共振回路を用いて高調波成分の周波数の信号を発生することができるという効果がある。
【００９０】
請求項３の発明は、請求項１または２において、前記高調波成分の周波数は、前記高周波インバータ回路の発振周波数の奇数倍の高調波成分の周波数であるので、交流に近く、直流成分が小さい波形を発生する装置は、容易に高調波成分の周波数の信号を発生することができるという効果がある。
【００９１】
請求項４の発明は、請求項３において、前記奇数倍の高調波成分は第３次高調波成分であるので、第２のコイルの出力を半波整流する回路と定電圧負荷とを備えた構成では、容易に高調波成分の周波数の信号を発生することができるという効果がある。
【００９２】
請求項５の発明は、請求項１乃至４いずれかにおいて、前記電力変換回路は、第２のコイルの出力を半波整流する回路を備えるので、低コスト化を図ることができるという効果がある。
【００９３】
請求項６の発明は、請求項１乃至５いずれかにおいて、前記信号受信回路は、前記入力信号コイルに接続した共振コンデンサを備え、前記高調波成分の周波数に共振するので、確実な信号検出を行うことができるという効果がある。
【００９４】
請求項７の発明は、請求項１乃至６いずれかにおいて、前記入力信号コイルは、差動接続した第４のコイルと第５のコイルとからなるので、第４のコイルと第５のコイルとで検出した信号を差動出力して大きくすることができるという効果が有る。
【００９５】
請求項８の発明は、請求項１乃至７いずれかにおいて、前記非接触給電装置に前記非接触受電装置が概略、対向配置されて、前記非接触受電装置が給電を要求する場合に、前記信号発生装置の出力が大きくなるので、受電側の状況を識別することができるという効果がある。
【００９６】
請求項９の発明は、請求項１乃至８いずれかにおいて、前記非接触給電装置に前記非接触受電装置が概略、対向配置されて、前記非接触受電装置が給電を拒否する場合に、前記２次側制御回路は前記信号発生装置の出力を低減させるので、請求項８と同様の効果を奏する。
【００９７】
請求項１０の発明は、請求項１乃至９いずれかにおいて、前記非接触給電装置が単独で存在する場合に、前記高周波インバータ回路は間欠発振を行うので、省エネルギー化、及び金属異物の過熱対策を図ることができるという効果がある。
【００９８】
請求項１１の発明は、請求項２乃至１０いずれかにおいて、前記高周波インバータ回路は、発振用スイッチング素子と、発振用スイッチング素子の制御端をグランドレベルに接続する自励制御用スイッチング素子とを備えて自励発振を行い、前記インバータ制御回路は、前記自励制御用スイッチング素子の発振を間欠に停止させることで前記発振用スイッチング素子の発振動作を間欠停止させる強制停止回路と、前記入力信号コイルの出力でオンすることにより前記強制停止回路の間欠停止動作を停止させる発振切替用スイッチング素子とを備え、
前記非接触給電装置が単独である場合、前記入力信号コイルの出力電圧は前記発振切替用スイッチング素子がオフとなる電圧に維持され、前記強制停止回路が動作して前記発振用スイッチング素子の発振動作を間欠発振に制御し、
前記非接触給電装置に前記非接触受電装置が概略、対向配置されて、前記非接触受電装置が給電を要求する場合、前記信号発生装置は、前記発振用スイッチング素子の発振動作が間欠発振である期間に発生した前記非接触給電装置及び非接触受電装置内の磁場、磁束、あるいは前記非接触受電装置内の電圧または電流情報から取り出した前記高調波成分の周波数の信号で第３のコイルを励磁し、第３のコイルと概略、対向配置されて、第３のコイルで発生した磁束を検出する前記入力信号コイルの出力電圧は前記発振切替用スイッチング素子がオンとなる電圧になり、前記強制停止回路が動作を停止して前記発振用スイッチング素子の発振動作を連続発振に制御し、
前記非接触給電装置に前記非接触受電装置が概略、対向配置されて、前記非接触受電装置が給電を拒否する場合、前記信号発生装置は、前記高調波成分の周波数の信号を低減させて第３のコイルの励磁を抑制し、前記入力信号コイルの出力電圧は前記発振切替用スイッチング素子がオフとなる電圧になり、前記強制停止回路が動作して前記発振用スイッチング素子の発振動作を間欠発振に制御するので、非接触給電装置に自励制御インバータを用いて、識別した受電側の状況に応じて連続発振と間欠発振とを切替えることができるという効果がある。
【００９９】
請求項１２の発明は、請求項２乃至１１いずれかにおいて、前記非接触受電装置は、第３のコイルとコンデンサとからなる共振回路の少なくとも一部を短絡または開放する補助スイッチング素子を備え、前記非接触給電装置に前記非接触受電装置が概略、対向配置されて、前記非接触受電装置が給電を拒否する場合に、前記２次側制御回路は、前記補助スイッチング素子を動作させて、前記信号発生装置の共振回路が発生する信号の周波数、振幅、波形のうち少なくとも１つを給電を必要とする場合の周波数、振幅、波形に対して変化させて、前記入力信号コイルは前記信号発生装置が発生した信号を検出し、前記インバータ制御回路は前記入力信号コイルが検出した信号に基づいて前記高周波インバータ回路を制御して、前記非接触給電装置から前記非接触受電装置への給電を低減させるので、補助スイッチング素子をオン・オフすることで信号発生装置が発生する信号を変化させて、受電側の状況を識別して電力供給制御を行うことができるという効果がある。
【０１００】
請求項１３の発明は、請求項２乃至１１いずれかにおいて、前記非接触受電装置は、前記信号発生装置以外の内部回路の少なくとも一部を短絡または開放する補助スイッチング素子を備え、前記非接触給電装置に前記非接触受電装置が概略、対向配置されて、前記非接触受電装置が給電を拒否する場合に、前記２次側制御回路は、前記補助スイッチング素子を動作させて、前記信号発生装置の共振回路が発生する信号の周波数、振幅、波形のうち少なくとも１つを、給電を必要とする場合の周波数、振幅、波形に対して変化させて、前記入力信号コイルは前記信号発生装置が発生した信号を検出し、前記インバータ制御回路は前記入力信号コイルが検出した信号に基づいて前記高周波インバータ回路を制御して、前記非接触給電装置から前記非接触受電装置への給電を低減させるので、請求項１２と同様の効果を奏する。
【０１０１】
請求項１４の発明は、請求項１３において、前記非接触受電装置は、第１のコイルが発生する磁束の少なくとも一部が鎖交する補助コイルと、前記補助コイルを短絡または開放する補助スイッチング素子とを備え、前記非接触給電装置に前記非接触受電装置が概略、対向配置されて、前記非接触受電装置が給電を拒否する場合に、前記２次側制御回路は、前記補助スイッチング素子を動作させて、前記信号発生装置の共振回路が発生する信号の周波数、振幅のうち少なくとも１つを給電を必要とする場合の周波数、振幅に対して小さくするので、請求項１２と同様の効果を奏する。
【０１０２】
請求項１５の発明は、請求項１２において、前記信号発生装置は、第３のコイルとコンデンサとを並列接続した共振回路からなり、前記並列回路の両端間にダイオードと補助スイッチング素子との直列回路を備え、前記非接触給電装置に前記非接触受電装置が概略、対向配置されて、前記非接触受電装置が給電を拒否する場合は、前記２次側制御回路が前記補助スイッチング素子をオンさせて、第３のコイルの励磁を抑制するので、請求項１２と同様の効果を奏する。
【０１０３】
請求項１６の発明は、請求項１３において、前記非接触受電装置は、第２のコイルを短絡または開放する補助スイッチング素子を備え、前記非接触給電装置に前記非接触受電装置が概略、対向配置されて、前記非接触受電装置が給電を拒否する場合は、前記２次側制御回路は、前記補助スイッチング素子を動作させて、前記信号発生装置の共振回路が発生する信号の周波数、振幅のうち少なくとも１つを、給電を必要とする場合の周波数、振幅に対して小さくするので、請求項１２と同様の効果を奏する。
【０１０４】
請求項１７の発明は、請求項１２乃至１６いずれかにおいて、前記補助スイッチング素子は一方向に導通する素子であるので、補助スイッチング素子を容易に選定することができるという効果がある。
【０１０５】
請求項１８の発明は、請求項１２乃至１７いずれかにおいて、前記補助スイッチング素子に直列接続したコンデンサを備えるので、補助スイッチング素子をオン・オフすることで、信号発生装置が発生する信号の周波数を大きく変化させて、受電側の状況判別を、より確実に行うことができるという効果がある。
【０１０６】
請求項１９の発明は、請求項１２乃至１７いずれかにおいて、前記補助スイッチング素子に並列接続したコンデンサを備えるので、請求項１８と同様の効果を奏する。
【０１０７】
請求項２０の発明は、請求項１乃至１９いずれかにおいて、第２のコイルと第３のコイルとの磁気結合は疎結合であるので、第２のコイルのコイル電流による影響を受けずに、第３のコイルは磁束を発生することができるという効果がある。
【０１０８】
請求項２１の発明は、請求項１乃至２０いずれかにおいて、前記入力信号コイルの出力部に、前記高調波成分の周波数と同じ周波数帯域を検出するフィルタを備えたので、確実な信号検出を行うことができるという効果がある。。
【０１０９】
請求項２２の発明は、請求項１乃至２１いずれかにおいて、前記高周波インバータ回路は、第１のコイルの両端間に正弦波状の交番電圧を印加するので、高周波インバータ回路として電圧共振型のインバータ回路を用いることができるという効果がある。
【０１１０】
請求項２３の発明は、請求項１乃至２２いずれかにおいて、前記高周波インバータ回路は、発振用スイッチング素子と、前記発振用スイッチング素子または第１のコイルに並列接続した共振コンデンサとを備えた一石の電圧共振インバータであるので、第１のコイルの両端間に正弦波状の交番電圧を印加することができるという効果がある。
【０１１１】
請求項２４の発明は、請求項７乃至２３いずれかにおいて、前記入力信号コイルを構成する差動接続した第４、第５のコイルと第１のコイルとの磁気結合は疎結合であり、第４のコイルと第５のコイルとのうちいずれか一方と第３のコイルとの磁気結合度は、第４のコイルと第５のコイルとのうちいずれか他方と第３のコイルとの磁気結合度より大きいので、第４のコイルと第５のコイルとの差動出力を得ることができるという効果がある。
【０１１２】
請求項２５の発明は、請求項２４において、第４，第５のコイルは第１のコイルに対し対称な位置に配置され、第３のコイルは、第４のコイルと第５のコイルとのうちいずれか一方に対向して配置されるので、第４のコイルと第５のコイルとの差動出力に対する第１のコイルで発生する磁束の影響を小さくすることができ、且つ、第３のコイルと第４のコイルとの磁気結合度と、第３のコイルと第５のコイルとの磁気結合度とを異ならせることができるという効果がある。
【０１１３】
請求項２６の発明は、請求項１において、非接触給電装置から非接触受電装置への給電が行われているとき、第２のコイルの両端電圧、コイル電流は歪んだ波形となり、前記信号発生装置は、第２のコイルの両端電圧、コイル電流に含まれる高調波成分を発生源とした信号を発生するので、信号発生装置を容易に構成することができるという効果がある。
【０１１４】
請求項２７の発明は、請求項２６において、前記入力信号コイルを構成する差動接続した第４、第５のコイルと第１のコイルとの磁気結合は疎結合であり、第４のコイルと第５のコイルとのうちいずれか一方と第２のコイルとの磁気結合度は、第４のコイルと第５のコイルとのうちいずれか他方と第２のコイルとの磁気結合度より大きいので、第２のコイルが発生する磁束による差動出力を得ることができるという効果がある。
【０１１５】
請求項２８の発明は、請求項１乃至２７いずれかにおいて、前記信号発生装置は、前記高調波成分の周波数の共振周波数を有する第３のコイルとコンデンサとの共振回路による信号発生手段と、第２のコイルの両端電圧、コイル電流に含まれる高調波成分を発生源とした信号を発生する信号発生手段とを備えるので、受電側の状況をより判別しやすい信号を、信号発生装置で発生することができるという効果がある。
【０１１６】
請求項２９の発明は、請求項１乃至２５，２８いずれかにおいて、前記信号発生装置は、第３のコイルに直列接続したインダクタを備えるので、第３のコイルのインダクタンスが小さい場合でも、電流による損失を低減することができるという効果がある。
【図面の簡単な説明】
【図１】本発明の実施形態１のブロック構成を示す図である。
【図２】同上の第１の回路構成を示す図である。
【図３】同上の起動から連続発振に至る各部の波形を示す図である。
【図４】同上の起動から間欠発振に至る各部の波形を示す図である。
【図５】同上の分離着脱式トランスの構造例を示す側面断面図である。
【図６】同上の分離着脱式トランスの構造例の１次側を示す側面断面図である。
【図７】同上の第２の回路構成を示す図である。
【図８】同上の第３の回路構成を示す図である。
【図９】同上の第４の回路構成を示す図である。
【図１０】本発明の実施形態２の第２のコイルの両端電圧波形を示す図である。
【図１１】同上の２次側の等価回路を示す図である。
【図１２】同上の分離着脱式トランスの構造例を示す側面断面図である。
【図１３】本発明の実施形態３の回路構成を示す図である。
【符号の説明】
１非接触給電装置
２非接触受電装置
１１高周波インバータ回路
１２信号受信回路
１３インバータ制御回路
２１電力変換回路
２３２次側制御回路
２４信号発生装置
３０負荷
Ｌ１〜Ｌ５第１〜第５のコイル
Ｌｓ入力信号用コイル
Ｃ４，Ｃ８共振コンデンサ
Ｓ２スイッチ[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a non-contact power feeding system.
[0002]
[Prior art]
In recent years, the adoption of non-contact power transmission technology for portable electronic devices, electric vehicles, industrial devices, and the like has been spreading. This technology is especially useful for products used around water, such as electric toothbrushes and electric shavers. In a non-contact power supply system that uses the power supply side (power supply side) and the load side (power reception side) in a detachable manner, when power is supplied from the power supply side to the load side by electromagnetic induction, the power is supplied when the load side is removed. It is necessary to stop the oscillation of the oscillation switching element used in the supply-side inverter circuit or reduce the oscillation intensity. The reason for this is that if oscillation is continued when there is no load, energy is wasted due to power loss on the power supply side, and if a metallic foreign object other than the correct load is placed, for example, induction heating is performed. This is because the action causes an abnormal overheating of the metal and is dangerous. Furthermore, when the load is a secondary battery or the like, it is necessary to perform charge control when the secondary battery is fully charged.
[0003]
In other words, for non-contact power transmission, “power saving control and oscillation stop or suppression control for measures against metal foreign matter overheating when the power supply is alone”, “continuous power supply control when a correct load is attached” and “ Three types of control, “power transmission control based on a request from the load side”, are necessary.
[0004]
[Problems to be solved by the invention]
Several conventional examples that satisfy all or part of the above three controls have been proposed. For example, there is a technique disclosed in Japanese Patent Laid-Open No. 6-311658. This is because an independent pair of signal coils is provided separately from the pair of power coils on the power supply side and the load side, and when the load is mounted, power is supplied to the load by induction of the pair of power coils. Is transmitted. Then, the control circuit on the load side is driven using this power, the control signal is returned from the load side to the power supply side by a pair of signal coils, and the power supply side controls the oscillation operation based on this control signal. To do.
[0005]
However, this configuration requires separate circuits for load detection and oscillation control, and in order to make it easier to distinguish the signal frequency from the frequency for power transmission and reception, it is necessary to increase the signal frequency. There is a drawback that the generation circuit becomes complicated, and the size and cost are increased due to enhancement of noise countermeasures.
[0006]
Japanese Patent Application Laid-Open No. 11-178249 utilizes the characteristics of self-excited oscillation, and a positive feedback loop is once taken out from the power supply side to the load side and returned to the power supply side, and the feedback loop is used for load information. In this circuit, the load can be detected with a very simple circuit that can save power and prevent overheating of the foreign metal. Furthermore, since the same power frequency and signal frequency can be used, non-contact power transmission can be performed with a simple configuration. However, since the control signal is a positive feedback feedback signal having the same frequency as the power frequency, there is a drawback in that amplification control of the signal amplitude cannot be performed and it is difficult to obtain a noise margin.
[0007]
The present invention has been made in view of the above-described reasons, and an object thereof is to provide a non-contact power supply system having a simple structure that can perform power supply control by identifying the situation on the power receiving side. It is in.
[0008]
[Means for Solving the Problems]
The invention according to claim 1 is a high-frequency inverter circuit that outputs high-frequency power, an inverter control circuit that controls the high-frequency inverter circuit, and a first coil that is supplied with high-frequency power from the high-frequency inverter circuit and performs power supply by magnetic coupling And a signal receiving circuit having an input signal coil, wherein the inverter control circuit controls the high-frequency inverter circuit based on a signal detected by the input signal coil, and
A second coil disposed opposite to the first coil and receiving power by magnetic coupling; a power conversion circuit for converting the output of the second coil into predetermined electrical energy; and an oscillation frequency of the high-frequency inverter circuit A signal generation device that generates a signal having a frequency of a harmonic component, a secondary-side control circuit that controls a signal generated by the signal generation device, and a load that is supplied with electrical energy from the power conversion circuit It consists of a contact power receiving device,
The first coil and the second coil have a transformer structure that is detachable from each other, and the input signal coil receives a signal that detects the presence or absence of the non-contact power receiving device and a signal that is generated by the signal generating device. The detected signal is output.
[0009]
According to a second aspect of the present invention, in the first aspect, the signal generation device is a resonance circuit including a third coil and a capacitor and having a resonance frequency of the harmonic component, and the contactless power supply device. When the non-contact power receiving device is roughly arranged opposite to each other, the harmonics extracted from the magnetic field, magnetic flux in the non-contact power feeding device and the non-contact power receiving device, or the voltage or current information in the non-contact power receiving device. A frequency signal of the component is generated, the input signal coil detects a signal of the frequency of the harmonic component, and the inverter control circuit controls the high frequency inverter circuit based on the signal detected by the input signal coil. The power supply control from the non-contact power supply apparatus to the non-contact power reception apparatus is performed.
[0010]
A third aspect of the invention is characterized in that, in the first or second aspect, the frequency of the harmonic component is a frequency of a harmonic component that is an odd multiple of the oscillation frequency of the high-frequency inverter circuit.
[0011]
The invention of claim 4 is characterized in that, in claim 3, the odd harmonic component is a third harmonic component.
[0012]
According to a fifth aspect of the present invention, in any one of the first to fourth aspects, the power conversion circuit includes a circuit for half-wave rectifying the output of the second coil.
[0013]
According to a sixth aspect of the present invention, in any one of the first to fifth aspects, the signal receiving circuit includes a resonance capacitor connected to the input signal coil, and resonates at a frequency of the harmonic component.
[0014]
A seventh aspect of the invention is characterized in that in any one of the first to sixth aspects, the input signal coil includes a fourth coil and a fifth coil which are differentially connected.
[0015]
The invention according to claim 8 is the signal according to any one of claims 1 to 7, wherein the non-contact power receiving device is disposed substantially opposite to the non-contact power feeding device, and the non-contact power receiving device requests power feeding. The output of the generator is increased.
[0016]
A ninth aspect of the present invention provides the method according to any one of the first to eighth aspects, wherein the non-contact power receiving device is disposed substantially opposite to the non-contact power feeding device, and the non-contact power receiving device rejects power feeding. The secondary control circuit reduces the output of the signal generator.
[0017]
According to a tenth aspect of the present invention, in any one of the first to ninth aspects, the high-frequency inverter circuit performs intermittent oscillation when the non-contact power feeding device is present alone.
[0018]
An eleventh aspect of the present invention is that in any one of the second to tenth aspects, the high-frequency inverter circuit includes an oscillation switching element and a self-excitation control switching element that connects a control terminal of the oscillation switching element to a ground level. A self-excited oscillation, and the inverter control circuit intermittently stops the oscillation of the switching element for oscillation by intermittently stopping the oscillation of the switching element for self-excitation, and the input signal coil An oscillation switching switching element that stops the intermittent stop operation of the forced stop circuit by being turned on with an output of
When the contactless power feeding device is single, the output voltage of the input signal coil is maintained at a voltage at which the oscillation switching switching element is turned off, and the forced stop circuit operates to oscillate the oscillation switching element. Is controlled to intermittent oscillation,
When the non-contact power receiving device is disposed substantially opposite to the non-contact power feeding device, and the non-contact power receiving device requests power feeding, the signal generating device is configured such that the oscillation operation of the oscillation switching element is intermittent oscillation. The third coil is excited by a signal of the frequency of the harmonic component extracted from the magnetic field or magnetic flux in the non-contact power feeding device and the non-contact power receiving device generated during the period, or the voltage or current information in the non-contact power receiving device. The output voltage of the input signal coil, which is arranged roughly opposite to the third coil and detects the magnetic flux generated in the third coil, is a voltage at which the oscillation switching switching element is turned on, and the forced stop The circuit stops operating and controls the oscillation operation of the oscillation switching element to continuous oscillation,
When the non-contact power receiving device is roughly disposed opposite to the non-contact power feeding device, and the non-contact power receiving device rejects power feeding, the signal generator reduces the frequency signal of the harmonic component and 3 is suppressed, the output voltage of the input signal coil becomes a voltage at which the oscillation switching element is turned off, and the forced stop circuit operates to intermittently oscillate the oscillation operation of the oscillation switching element. It is characterized by controlling to.
[0019]
A twelfth aspect of the present invention is the contactless power receiving device according to any one of the second to eleventh aspects, further comprising an auxiliary switching element that short-circuits or opens at least a part of a resonance circuit including a third coil and a capacitor. When the non-contact power receiving device is disposed substantially opposite to the non-contact power feeding device and the non-contact power receiving device rejects power feeding, the secondary control circuit operates the auxiliary switching element to By changing at least one of the frequency, amplitude, and waveform of the signal generated by the resonance circuit of the generator with respect to the frequency, amplitude, and waveform when power supply is required, the input signal coil is changed by the signal generator. The generated signal is detected, and the inverter control circuit controls the high-frequency inverter circuit based on the signal detected by the input signal coil, thereby Wherein the reducing the power supply to the non-contact power receiving apparatus from.
[0020]
The invention of claim 13 is the contactless power receiving device according to any one of claims 2 to 11, wherein the contactless power receiving device includes an auxiliary switching element that short-circuits or opens at least a part of an internal circuit other than the signal generator. When the non-contact power receiving device is generally disposed opposite to the device, and the non-contact power receiving device rejects power feeding, the secondary control circuit operates the auxiliary switching element to The signal generator generates the input signal coil by changing at least one of the frequency, amplitude, and waveform of the signal generated by the resonance circuit with respect to the frequency, amplitude, and waveform when power supply is required. Detecting the signal, the inverter control circuit controls the high-frequency inverter circuit based on the signal detected by the input signal coil, and Non-contact power supply system in accordance with claim 2 to 11, wherein the reducing the power supply to the contact power receiving apparatus.
[0021]
According to a fourteenth aspect of the present invention, in the thirteenth aspect, the non-contact power receiving device includes an auxiliary coil in which at least a part of the magnetic flux generated by the first coil is linked, and an auxiliary switching element that short-circuits or opens the auxiliary coil. When the non-contact power receiving device is generally disposed opposite to the non-contact power feeding device, and the non-contact power receiving device rejects power feeding, the secondary side control circuit operates the auxiliary switching element. Thus, at least one of the frequency and amplitude of the signal generated by the resonance circuit of the signal generator is made smaller than the frequency and amplitude when power supply is required.
[0022]
A fifteenth aspect of the present invention is the signal generator according to the twelfth aspect, wherein the signal generating device includes a resonance circuit in which a third coil and a capacitor are connected in parallel, and a series circuit of a diode and an auxiliary switching element between both ends of the parallel circuit. And when the non-contact power receiving device rejects power feeding, the secondary control circuit turns on the auxiliary switching element. The excitation of the third coil is suppressed.
[0023]
According to a sixteenth aspect of the present invention, in the thirteenth aspect, the non-contact power receiving device includes an auxiliary switching element that short-circuits or opens the second coil, and the non-contact power receiving device is substantially opposed to the non-contact power feeding device. When the non-contact power receiving apparatus rejects power feeding, the secondary control circuit operates the auxiliary switching element, and out of the frequency and amplitude of the signal generated by the resonance circuit of the signal generating apparatus. At least one is characterized in that it is made smaller with respect to the frequency and amplitude when power supply is required.
[0024]
According to a seventeenth aspect of the present invention, in any one of the twelfth to sixteenth aspects, the auxiliary switching element is an element that conducts in one direction.
[0025]
According to an eighteenth aspect of the present invention, in any one of the twelfth to seventeenth aspects, a capacitor connected in series to the auxiliary switching element is provided.
[0026]
A nineteenth aspect of the invention is characterized in that in any one of the twelfth to seventeenth aspects, a capacitor connected in parallel to the auxiliary switching element is provided.
[0027]
According to a twentieth aspect of the present invention, in any one of the first to nineteenth aspects, the magnetic coupling between the second coil and the third coil is loose coupling.
[0028]
A twenty-first aspect of the invention is characterized in that, in any one of the first to twentieth aspects, the output section of the input signal coil includes a filter that detects the same frequency band as the frequency of the harmonic component.
[0029]
According to a twenty-second aspect of the present invention, in any one of the first to twenty-first aspects, the high-frequency inverter circuit applies a sinusoidal alternating voltage between both ends of the first coil.
[0030]
According to a twenty-third aspect of the present invention, in any one of the first to twenty-second aspects, the high frequency inverter circuit includes a switching element for oscillation and a resonant capacitor connected in parallel to the switching element for oscillation or the first coil. It is a voltage resonance inverter.
[0031]
According to a twenty-fourth aspect of the present invention, in any one of the seventh to twenty-third aspects, the magnetic coupling between the fourth and fifth coils and the first coil, which constitute the input signal coil, is loosely coupled. The degree of magnetic coupling between any one of the fourth coil and the fifth coil and the third coil is the magnetic coupling between the other of the fourth coil and the fifth coil and the third coil. It is characterized by greater than degrees.
[0032]
According to a twenty-fifth aspect of the present invention, in the twenty-fourth aspect, the fourth and fifth coils are arranged symmetrically with respect to the first coil, and the third coil is composed of the fourth coil and the fifth coil. It is arranged to face either one of them.
[0033]
According to a twenty-sixth aspect of the present invention, in the first aspect, when power is supplied from the non-contact power supply device to the non-contact power reception device, the both-end voltage and coil current of the second coil have a distorted waveform, and the signal generation The apparatus is characterized in that a signal is generated using a harmonic component included in the voltage across the second coil and the coil current as a generation source.
[0034]
According to a twenty-seventh aspect of the present invention, in the twenty-sixth aspect, the magnetic coupling between the differentially connected fourth and fifth coils constituting the input signal coil and the first coil is a loose coupling, and the fourth coil The degree of magnetic coupling between one of the fifth coils and the second coil is greater than the degree of magnetic coupling between the other of the fourth coil and the fifth coil and the second coil. It is characterized by.
[0035]
The invention of claim 28 is the signal generator according to any one of claims 1 to 27, wherein the signal generator includes a signal generating means by a resonance circuit of a third coil and a capacitor having a resonance frequency of the harmonic component frequency, And a signal generating means for generating a signal using a harmonic component included in the two-end voltage of the coil and the coil current as a generation source.
[0036]
According to a twenty-ninth aspect of the present invention, in any one of the first to twenty-fifth and twenty-eighth aspects, the signal generator includes an inductor connected in series to a third coil.
[0037]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0038]
(Embodiment 1)
FIG. 1 shows a block diagram of the contactless power supply system of the present embodiment. The non-contact power supply system includes a non-contact power supply apparatus 1 that supplies power and a non-contact power reception apparatus 2 that includes a load to which power is supplied. The non-contact power supply apparatus 1 outputs a high-frequency inverter circuit 11 that outputs high-frequency power. An inverter control circuit 13 for controlling the high-frequency inverter circuit 11, a first coil L1 that is supplied with high-frequency power from the high-frequency inverter circuit 11 and supplies power by magnetic coupling, and a differential connection in series with opposite polarities. Both ends of the differential connection circuit for amplifying the output of the differential connection circuit of the fourth coil L4 and the fifth coil L5, and the input signal coil Ls including the fourth coil L4 and the fifth coil L5. A signal receiving circuit 1 including a resonance capacitor C4 connected therebetween, wherein the fourth coil L4, the fifth coil L5, and the resonance capacitor C4 operate as a differential resonance circuit. Constitute a.
[0039]
The non-contact power receiving apparatus 2 has a load 30. The second coil L 2 is disposed opposite to the first coil L 1 and receives power by magnetic coupling, and the output of the second coil L 2 is supplied to the load 30. Connected to both ends of the third coil L3, a power conversion circuit 21 for converting the output into a suitable output, a third coil L3 disposed opposite to the input signal coil Ls of the signal receiving circuit 12, and A resonance capacitor C8, a switch S2 connected between both ends of the resonance capacitor C5, and a secondary-side control circuit 23 that outputs a signal for controlling on / off of the switch S2, a third coil L3 and the resonance capacitor C8 are provided. Constitutes a signal generating device 24 that outputs a signal from the non-contact power receiving device 2.
[0040]
The non-contact power feeding system as described above has a transformer structure in which the first coil L1 and the second coil L2 are detachable and detachable, and the first coil L1 supplied with high-frequency power from the high-frequency inverter circuit 11 is used. An induced voltage is generated in the second coil L2 by the magnetic flux generated, and the induced voltage is converted into a predetermined form by the power conversion circuit 21 and output to the load 30. The signal generator 24 generates a signal having the same frequency as the harmonic of the oscillation frequency of the high-frequency inverter circuit 11, the input signal coil Ls detects this signal, and the inverter control circuit 13 based on this detection signal. The oscillation of the high frequency inverter circuit 11 is controlled.
[0041]
Here, the first coil L1 and the input signal coil Ls are arranged so as to be magnetically loosely coupled, and the fourth coil L4 and the fifth coil L5 are also arranged so as to be magnetically loosely coupled. Has been. A third coil L3 is disposed on the secondary side so as to face the fourth coil L4 on the primary side. Magnetically loosely coupled means a state in which all of the magnetic flux generated by one coil is not linked to the other coil. For example, even if the magnetic core is on the axis of the coil, each coil is completely connected. If they are arranged close to each other in the axial direction or in the radial direction without overlapping, they become loosely coupled.
[0042]
Next, the configuration of each unit will be described in detail using the specific circuit configuration shown in FIG. First, the high-frequency inverter circuit 11 of the non-contact power feeding device 1 is a self-excited oscillation circuit, a series circuit of a resistor R2 and a capacitor C1 connected in parallel to a series circuit of a DC power source E1 and a switch S1, a resonance capacitor C2, A series circuit of an oscillation switching element FET1 and a resistor R1 is provided, and a first coil L1 is connected in parallel to the resonance capacitor C2. A feedback coil L6 that is tightly coupled with the first coil and the polarity shown in the figure is connected between the connection middle point of the resistor R2 and the capacitor C1 and the gate of the switching element FET1. A switching element Tr1 for controlling self-excited oscillation connected in parallel to the capacitor C1 via the feedback coil L6 is an element that controls oscillation of the switching element FET1. A resistor R3 is connected between the source of the switching element FET1 and the base of the switching element Tr1, and a capacitor C3 is connected between the base and emitter of the switching element Tr1.
[0043]
The configuration of the signal receiving circuit 12 is the same as that of FIG. 1, and one output terminal is connected to the ground of the high-frequency inverter circuit (the low voltage output side of the DC power supply E1).
[0044]
The inverter control circuit 13 is a circuit that controls the oscillation of the high-frequency inverter circuit 11 in two ways of continuous oscillation and intermittent oscillation by turning on and off the switching element Tr1 for controlling self-excited oscillation of the high-frequency inverter circuit 11. The other end of the series circuit of the diode D3, the Zener diode ZD1, and the resistor R7, each having one end connected to the other output end of the signal receiving circuit 12, is connected to the base of the switching element Tr2 for switching oscillation. A capacitor C5 is connected between the output terminals of the signal receiving circuit 12 via a diode D3, and a resistor R8 is connected between the base and emitter of the switching element Tr2. The drain of the switching element FET1 is connected to the ground level via a series circuit of resistors R4 and R5, and the capacitor C6 is connected in parallel to the resistor R5 via a diode D2. The midpoint of connection between the diode D2 and the capacitor C6 is connected to the base of the switching element Tr1 for self-excited oscillation control via the diode D1 and the resistor R3, and further connected to the collector of the transistor Tr2 via the resistor R6. is doing. Here, the resistors R4 and R5, the diodes D1 and D2, and the capacitor C6 constitute a forced stop circuit 15 that intermittently stops the oscillation operation of the switching element FET1.
[0045]
The secondary circuit 21 of the non-contact power receiving device 2 includes a capacitor C7 connected between the output ends of the second coil L2, and a rectifying diode D4 connected in series to one output end of the second coil L2. In addition, an output obtained by half-wave rectifying the induced voltage of the second coil L 2 is supplied to the secondary battery 22 as a load, and both ends of the secondary battery 22 are connected to the secondary-side control circuit 23.
[0046]
A resonant capacitor C8 and a series circuit of a diode D5 and an auxiliary switching element Tr3 are connected between both ends of the third coil L3, and the base of the auxiliary switching element Tr3 is connected to the secondary side control circuit 23.
[0047]
Next, the process from the start of oscillation to the continuous oscillation from when the switch S1 is turned on will be described with reference to the waveform diagram shown in FIG. First, when the switch S1 is turned on, the DC power source E1 that generates the voltage Ve1 charges the capacitor C1 through the resistor R2. At this time, since no induced voltage is generated in the feedback coil L6 that is tightly coupled to the first coil L1, the gate voltage Vg of the switching element FET1 is equal to the voltage Vc1 of the capacitor C1. When the gate voltage Vg gradually increases and reaches the voltage Vgon that can turn on the switching element FET1, the switching element FET1 is turned on, and the drain voltage Vd becomes substantially zero potential. At this time, the resonance voltage Vc2 at both ends of the resonance capacitor C2 connected in parallel with the first coil L1 is charged by the power supply voltage Ve1 of the DC power supply E1, and the first coil L1 has a substantially monotonically increasing coil current. IL1 begins to flow.
[0048]
When the coil current IL1 starts to flow, an induced voltage is generated in the second coil L2 by the action of the transformer. Similarly, an induced voltage Vf1 is also generated in the feedback coil L6 that is tightly coupled to the first coil L1. Then, the gate voltage Vg viewed from the ground level becomes Vc1 + Vf1, and the switching element FET1 is rapidly turned on stably.
[0049]
The coil current IL1 is substantially equal to the drain current Id flowing through the switching element FET1 to the resistor R1, and the voltage Vtr1 of the resistor R1 increases with time. When the voltage Vtr1 reaches a voltage at which the switching element Tr1 can be turned on, the switching element Tr1 starts to turn on. When the switching element Tr1 begins to turn on, the gate input capacitance of the switching element FET1 and the charge accumulated in the capacitance of the capacitor C1 via the feedback coil L6 begin to be extracted, and the voltage Vc1 and the gate voltage Vg begin to decrease. As the gate voltage Vg decreases, the switching element FET1 starts to shift to the off state, the on resistance increases, and the drain voltage Vd gradually increases.
[0050]
As the drain voltage Vd increases, the resonance voltage Vc2 also starts decreasing, and the induced voltage Vf1 of the feedback coil L6 also starts decreasing, so the gate voltage Vg further accelerates and decreases. As a result, the switching element FET1 is rapidly turned off, the voltage Vtr1 is also decreased, and the switching element Tr1 is turned off again.
[0051]
The resonance voltage Vc2 becomes a sine wave voltage due to the resonance action of the resonance capacitor C2 and the first coil L1, and the coil current IL1 also becomes a sine wave. During this time, the charging current from the DC power supply E1 to the capacitor C1 via the resistor R2 always flows, and the voltage Vc1 is increased again.
[0052]
When the resonance voltage Vc2 approaches the end of one cycle, the drain voltage Vd approaches the ground level, and the gate voltage Vg of the sum of the electromotive force Vf1 and the voltage Vc1 of the feedback coil L6 at that time turns on the switching element FET1 again. . Thereafter, the oscillation continues by repeating the above operation. This series of operations is performed except that the non-contact power receiving device 2 is not disposed opposite to the non-contact power feeding device 1, that is, even when the non-contact power feeding device 1 is alone, no electromotive force is generated in the second coil. The operation is similar.
[0053]
However, when the non-contact power feeding device 1 is used alone, it is necessary to stop or suppress the oscillation of the high-frequency inverter circuit 11 in order to save energy and protect the metal foreign matter from overheating. In the present embodiment, this role is achieved by making the oscillation of the high-frequency inverter circuit 11 intermittent by the forced stop circuit 15.
[0054]
Hereinafter, control of the intermittent oscillation operation will be described with reference to waveform diagrams of the respective parts shown in FIG. First, the process until the continuous oscillation is started after the switch S1 is turned on is the same as that described in FIG. The inverter control circuit 13 in FIG. 2 has an integration circuit that divides the drain voltage Vd by resistors R4 and R5 and accumulates charges in the capacitor C6 via the diode D2. The voltage of the capacitor C6 is connected to the base resistor R3 of the transistor Tr1 via the diode D1, and the voltage of the capacitor C6 is an input voltage value that can turn on the switching element Tr1, and each voltage drop of the diode D1 and the resistor R3. Is exceeded, the switching element Tr1 is turned on.
[0055]
When the switching element Tr1 is turned on, the charge accumulated in the gate input capacitance of the switching element FET1 and the capacitance of the capacitor C1 via the feedback coil L6 is extracted. At this time, if the ON time of the switching element Tr1 is kept long, the voltage Vc1 further decreases than the voltage in the steady oscillation state, and voltage recovery due to the charging current flowing from the DC power supply E1 to the capacitor C1 via the resistor R2 is recovered. The voltage of the steady state is not reached, and the switching element FET1 continues to be in the off state.
[0056]
Therefore, the next oscillation start-up is not performed until the voltage Vc1 due to only the charging current flowing from the DC power supply E1 to the capacitor C1 via the resistor R2 reaches the input voltage that can turn on the switching element FET1. That is, stable intermittent oscillation is obtained by repeating this operation.
[0057]
What is important for this intermittent oscillation is that the high-frequency inverter circuit 11 must first have a function of oscillating and then stopping with a time delay. The reason is that if the switching element Tr1 is turned on before the high frequency inverter circuit 11 oscillates, the oscillation is permanently stopped. In the oscillation stop state in the circuit of FIG. 2, since the potential of the drain voltage Vd becomes the power supply voltage Ve1, it is necessary to set the voltage dividing ratio of the resistors R4 and R5 to a value that does not turn on the switching element Tr1 in this oscillation stop state. is there. In order to reach a level at which the switching element Tr1 can be turned on after the oscillation starts, the capacitor C6 is gradually charged by using the voltage when the drain voltage Vd becomes higher than the power supply voltage Ve1 by the oscillation. Then, the voltage dividing ratio of the resistors R4 and R5 may be set so that the switching element Tr1 can be turned on after an appropriate time has elapsed. By configuring as described above, the high-frequency inverter circuit 11 and the inverter control circuit 13 illustrated in FIG. 2 can perform intermittent oscillation when the non-contact power feeding device 1 is alone.
[0058]
By the way, when the non-contact power receiving apparatus 2 is roughly disposed opposite to the non-contact power feeding apparatus 1 and needs to transmit power, a function for reliably stopping the intermittent oscillation is required. In order to perform the function of reliably stopping intermittent oscillation, that is, to perform continuous oscillation, a function for determining whether the load is correct when viewed from the non-contact power feeding apparatus 1 is necessary. A method of sending a predetermined signal from the non-contact power receiving device 2 to the non-contact power feeding device 1 is conceivable. Therefore, a signal generator 24 using a harmonic resonance circuit is required on the non-contact power receiving device 2 side. Hereinafter, this operation will be described.
[0059]
In the non-contact power feeding device 1, the outputs of the differential circuits of the fourth and fifth coils amplified by the resonance capacitor C4 are rectified by the diode D3 and charged to the capacitor C5. When the charging voltage of the capacitor C5 exceeds the sum of the input voltage value that can turn on the switching element Tr2, the Zener voltage of the Zener diode ZD1, and the voltage drop of the resistor R7, the switching element Tr2 is turned on. The charge of the capacitor C6 connected through the resistor R6 is extracted. Then, the transistor Tr1 cannot be turned on by the integration operation of the capacitor C6, and the intermittent oscillation of the switching element FET1 can be stopped and continuous oscillation can be performed.
[0060]
Therefore, when the non-contact power receiving apparatus 2 is generally arranged so as to face the non-contact power receiving apparatus 2 to transmit power, the non-contact power feeding apparatus 1 is roughly arranged to face the non-contact power receiving apparatus 2. This may be detected on the non-contact power receiving apparatus 2 side, and the detected result may be transmitted to the non-contact power feeding apparatus 1 using a signal unique to continuously oscillate.
[0061]
Here, the third coil L3 is set so that the signal generator 24 resonates at a frequency (third harmonic component) three times the oscillation frequency of the high-frequency inverter circuit 11 in the structure and specifications of the separation / detachment transformer used. And the resonant capacitor C8, when the third coil L3 of the signal generator 24 detects the magnetic flux generated by the first coil L1, this magnetic flux is used as the excitation source to detect the third coil L3. And the harmonic resonance circuit of the resonance capacitor C8 can increase the output amplitude of the signal generator 24. The third coil L3 is excited by a resonance current having a frequency of the third harmonic component, and this magnetic flux is detected by the input signal coil Ls to generate a large output voltage, thereby switching the oscillation switching element Tr2. By turning it on, the high-frequency inverter circuit 11 can continuously oscillate.
[0062]
Then, the signal receiving circuit 12 that operates as a differential resonance circuit including the fourth coil L4, the fifth coil L5, and the resonance capacitor C4 has the third harmonic component in the same manner as the signal generator 24 sets. If the output amplitude is set so as to increase in resonance with the frequency of the signal, more reliable signal detection can be performed.
[0063]
A specific operation of this signal detection operation will be described below. When the non-contact power feeding device 1 is alone, the input signal coil Ls of the signal receiving circuit 12 detects information on the primary side magnetic flux and magnetic field. If the high frequency inverter circuit 11 is a voltage resonance type inverter circuit, the voltage and current of the first coil L1 are substantially sinusoidal. Therefore, the third harmonic component is small, and the signal receiving circuit 12 outputs zero or a low voltage. If the third harmonic component is large, the signal receiving circuit 12 may be set so that the output voltage is small. Therefore, the switching element Tr2 remains off, and the high frequency inverter circuit 11 continues intermittent oscillation.
[0064]
Next, when the non-contact power receiving device 2 is arranged roughly opposite to the non-contact power feeding device 1 and needs power feeding, the magnetic flux generated in the first coil L1 during the intermittent oscillation period is generated by the signal generator 24. The third coil L3 is also linked, and the linked alternating magnetic flux generates an induced voltage having the oscillation frequency of the high-frequency inverter circuit 11 in the third coil L3, and the induced voltage causes the third coil L3 and The resonance capacitor C8 performs a series resonance operation. Since the series resonance frequency at this time is set to three times the oscillation frequency (fundamental wave), that is, the frequency of the third harmonic component, the third coil L3 has a frequency of the third harmonic component. A large alternating voltage is generated, and an alternating current having the frequency of the third harmonic component is passed through the third coil L3.
[0065]
Therefore, an AC voltage having a frequency of the third harmonic component is induced in the fourth coil L4 arranged to face the third coil L3, and the signal receiving circuit 12 has a frequency of the third harmonic component. The voltage rectified and smoothed by the diode D3 and the capacitor C5 turns on the switching element Tr2 to switch the high-frequency inverter circuit 11 from intermittent oscillation to continuous oscillation operation.
[0066]
Further, when the non-contact power receiving device 2 is roughly disposed opposite to the non-contact power feeding device 1 and needs to stop power feeding, the secondary control circuit 23 turns on the auxiliary switching element Tr3 and turns on the diode D5. If both ends of the signal generating device 24 are short-circuited via each other, the harmonic resonance function is lost, and the voltage of the frequency of the third harmonic component generated at both ends of the third coil L3 is zero or reduced. The output of 12 also becomes zero or a low voltage, and the voltage rectified and smoothed by the diode D3 and the capacitor C5 turns off the switching element Tr2, and the high frequency inverter circuit 11 becomes intermittent oscillation. The short-circuiting by the auxiliary switching element Tr3 does not need to be performed completely, and even if it is periodically short-circuited, there is a sufficient effect. Another method of reducing or eliminating the harmonic resonance function is to open a part of the circuit of the signal generator 24 so that no current flows without short-circuiting both ends of the signal generator 24. In this embodiment, since the short circuit is caused by the auxiliary switching element Tr3 via the diode D5, only one direction of the alternating current is short-circuited. The effect is sufficient.
[0067]
Next, FIG. 5 shows a side cross-sectional view of a structure in which the non-contact power receiving device 2 is roughly disposed opposite to the non-contact power feeding device 1 and forms a transformer structure that can be separated and attached. The separate detachable transformer includes first and second cores 14 and 25 made of a U-shaped magnetic body in order to reduce the magnetic resistance, and the first coil L1 is the first core 14. The third and fourth coils L3 and L4 sandwich the first coil L1 in the axial direction (symmetrically in the axial direction of the first coil L1). ), And is wound between the protrusions 14a and 14b, and the feedback coil L6 is sandwiched between the first coil L1 and the fifth coil L5 in the axial direction and wound between the protrusions 14a and 14b. The second coil L2 is wound between the protrusions 25a and 25b provided at both ends of the second core 25, and the third coil L3 is located at a position facing the fourth coil L4 between the protrusions 25a and 25b. The second coil L2 is wound separately in the axial direction.
[0068]
As described above, the feedback coil L6 for self-excited oscillation is arranged in the vicinity of the first coil L1 so that the magnetic flux generated by the first coil L1 is linked, and constitutes the input signal coil Ls. The fourth and fifth coils L4 and L5 are arranged away from the first coil L1 so as to be relatively loosely coupled to the magnetic flux generated by the first coil L1.
[0069]
The point here is that the fourth and fifth coils L4 and L5 are arranged so as not to be magnetically strongly coupled to the first coil L1. The reason is that the signal received by the fourth coil L4 from the third coil L3 must be valid and output greatly. If the fourth coil L4, the fourth coil L4, L5 and the first coil L1 must be output. Are magnetically coupled to each other, even if the magnetic flux signal generated by the third coil L3 is received, most of the output changes of the fourth and fifth coils L4 and L5 are the first coil L1. It is because it will be dominated by the magnetic flux change which generate | occur | produces.
[0070]
Further, the fourth and fifth coils L4 and L5 are differentially connected to output a difference between a change in the detection voltage at the fourth coil L4 and a change in the detection voltage at the fifth coil L5. This greatly shows the amplification effect of the output. That is, there is no effect if the induced voltages of the fourth and fifth coils L4 and L5 change in the same manner, and the detection voltage of only one coil needs to be changed. Therefore, the differentially connected fourth and fifth coils L4 and L5 may be provided with a magnetic coupling difference with respect to the third coil L3, and the fourth and fifth coils L4 and L5. Are arranged close to each other so that the magnetic coupling between one of the coils and the third coil L3 is dense, and the magnetic coupling between the other coil and the third coil L3 is arranged so as to be sparse. That's fine. In the present embodiment, the magnetic coupling between the fourth coil L4 and the third coil L3 is dense, and the third coil L3 is disposed at a location facing the fourth coil L4.
[0071]
At this time, most of the magnetic flux 100 generated by the third coil L3 is linked to the fourth coil L4, and few are linked to the fifth coil L5. Actually, the magnetic flux 100 generated by the third coil L3 is superimposed on the magnetic flux generated by the first coil L1 and the magnetic flux generated by the current flowing through the second coil L2. Due to the magnetic coupling relationship, the influence of the magnetic flux generated by the first coils L1 and L2 is such that the outputs of the differentially connected fourth and fifth coils L4 and L5 cancel each other, It is not output from the input signal coil Ls.
[0072]
However, the change in the magnetic flux generated by the third coil L3 can be linked to only the fourth coil L4, and a large output can be generated from the input signal coil Ls. In addition, in the present embodiment, the magnetic flux generated by the third coil L3 is not the oscillation frequency of the high-frequency inverter circuit 11, but the frequency of the third harmonic component, so the influence of the current of the first coil L1 The influence of the current of other coils can be further reduced.
[0073]
In addition, the third coil L3 is easily affected by the magnetic flux due to the current of the second coil L2, but by making the second coil L2 and the third coil L3 loosely coupled, Only the magnetic flux having the frequency of the harmonic component can be generated without being affected by the current.
[0074]
Next, FIG. 6 shows a side sectional view of the primary side of the separation / detachment type transformer when the non-contact power feeding device 1 is alone, and the first coil L1 generates a magnetic flux 101. FIG. What is important here is that the fourth and fifth coils L4 and L5 are wound apart symmetrically in the axial direction across the first coil L1, so that the coil current IL1 of the first coil L1 is The change of the interlinkage magnetic flux due to the generated magnetic flux 101 is the same for both the fourth and fifth coils L4 and L5, and the differential output can be zero or a small value.
[0075]
In the present embodiment, the signal generator 24 generates a magnetic flux having the third harmonic frequency of the oscillation frequency of the high-frequency inverter circuit 11, but the waveform having distortion is an integral multiple of the fundamental wave. The same effect can be obtained even if any harmonic is used. In particular, when the waveform is close to alternating current and the direct current component is small as in the present embodiment, the odd harmonics are dominant, and these odd harmonics can be used.
[0076]
By the way, in the case where the non-contact power receiving device 2 is generally disposed opposite to the non-contact power feeding device 1 and power feeding is rejected, the non-contact power feeding system shown in FIG. Although the circuit 11 is intermittently oscillated, a secondary circuit is connected by connecting a series circuit of a diode D8 and an auxiliary switching element Tr5 between the output ends of the second coil L2 as in the non-contact power feeding system shown in FIG. When the auxiliary switching element Tr5 is turned on by a signal from 23, the high-frequency inverter circuit 11 can be intermittently oscillated even if the output terminals of the second coil L2 are short-circuited. Further, as in the non-contact power feeding system shown in FIG. 8, the non-contact power receiving device 2 is provided with an auxiliary coil L7 and an auxiliary switching element Tr6 connected between both ends of the auxiliary coil L7, and a signal from the secondary control circuit 23 is provided. By turning on the auxiliary switching element Tr6, the high-frequency inverter circuit 11 can be intermittently oscillated even if the output terminals of the auxiliary coil L7 are short-circuited. This has the effect of weakening the magnetic flux by canceling out the magnetic flux generated by the first coil L1 by short-circuiting the second coil L2 and the auxiliary coil L7, so that the third coil L3 is chained as an excitation source. The output of the signal generator 24 can be reduced by reducing the magnetic flux of the intersecting first coil L1.
[0077]
As shown in FIG. 9, the output of the signal generator 24 can also be controlled by connecting a series circuit of an auxiliary switch S3 and a capacitor C10 between both ends of the third coil L3. This is because, when the auxiliary switch S3 is turned on, the capacitor C10 is connected in parallel to the resonance capacitor C8, so that the harmonic resonance frequency can be greatly changed and deviated from the resonance frequency set in the signal receiving circuit 12. Thus, the output of the signal receiving circuit 12 changes. Similarly, the output of the signal generator 24 can be controlled even if a capacitor is provided in series or in parallel with a switching element for controlling another coil.
[0078]
As described above, the contactless power supply system of the present embodiment uses a signal having the same frequency as the harmonic frequency of the power frequency to identify the power supply status and perform power supply control, thereby simplifying the circuit configuration and the transformer structure. Thus, the overall system size can be reduced and the cost can be reduced.
[0079]
In the non-contact power feeding system shown in FIGS. 1 and 7 to 9, the signal receiving circuit 12 uses a differential resonance circuit of the third and fourth coils L3 and L4 and the resonance capacitor C4. The feature is that the signal generating circuit 24 generates a magnetic flux of a specific harmonic frequency, and the signal receiving circuit 12 detects this magnetic flux. Therefore, the signal receiving circuit 12 detects from the signal detected by the input signal coil Ls. Any filter function that separates a signal of a specific harmonic frequency is sufficient.
[0080]
(Embodiment 2)
In the first embodiment, the load is a constant voltage load such as the secondary battery 22, but there are various loads such as a constant voltage load and a resistance load. Further, a rectifier circuit and a smoothing circuit are necessary to convert alternating current into direct current and supply it to the load. In the first embodiment, the secondary circuit is a half-wave rectifier circuit. The type of rectification, smoothing method and load is determined by the application purpose of the non-contact power supply system. In portable electronic devices such as electric toothbrushes and electric shavers, a secondary battery is used as a load, and the half-wave is low cost as a rectifier circuit. A rectifier circuit is often used. When such a secondary circuit or load is provided, for example, the second coil L2 can be provided without providing a circuit for generating a magnetic flux having a higher harmonic frequency, such as the signal generator 24, in the non-contact power receiving apparatus 2. If the current waveform contains many harmonic components, the information may be detected by the input signal coil Ls. FIG. 10 shows the waveform of the voltage Vl2 across the second coil L2 in the first embodiment. The voltage V10 during the half-wave rectifying diode D4 is conductive is the sum of the voltage drop of the secondary battery 22 and the diode D4. Is approximately equal to
[0081]
Further, since the first coil L1 and the second coil L2 are loosely coupled, the secondary-side equivalent leakage inductance La cannot be ignored as shown in the equivalent circuit of the secondary-side circuit in FIG. The voltage source AC1 induced in the second coil L2 is connected to the series circuit of the diode D4 and the secondary battery 22 through the inductance La inserted in series. In such a circuit, even if the induced voltage source AC1 is a sine wave, the voltage across the second coil L2 has a waveform far from the sine wave as shown in FIG. 10, and the period T0 changes to a sine wave. It is about three times as long as the running period T1. This indicates that the voltage V12 contains a lot of harmonic components (third harmonic) that is three times the fundamental wave.
[0082]
If the voltage waveform of the second coil L2 is as shown in FIG. 10, the magnetic flux component generated by the coil current of the second coil L2 has a strong influence on the entire detachable transformer unit. If the frequency of the third harmonic is selected and amplified, the operation of the high-frequency inverter circuit 11 is switched from intermittent oscillation to continuous oscillation simply by disposing the non-contact power receiving device 2 roughly opposite to the non-contact power feeding device 1. Can do. At this time, similarly to the first embodiment, the signal generator in which the third coil L3 and the resonance capacitor C8 are set so as to resonate at a frequency (third harmonic component) three times the oscillation frequency of the high-frequency inverter circuit 11 is used. If 24 is combined, it becomes more effective. Note that the voltage waveform V12 of the second coil L2 shown in FIG. 10 changes depending on the rectification condition, the load condition, and the like. Therefore, not only the third harmonic, but also the harmonic most contained in the voltage waveform at that time should be used. That's fine.
[0083]
Next, FIG. 12 shows a side sectional view of a detachable / detachable transformer structure that effectively extracts a harmonic component from the voltage / current waveform of the second coil L2. This detachable transformer is used to reduce the magnetic resistance. Are provided with first and second cores 14 and 25 made of a U-shaped magnetic body, and the first coil L1 is wound between protrusions 14a and 14b provided at both ends of the first core 14. The third and fourth coils L3 and L4 are wound between the protrusions 14a and 14b with the first coil L1 sandwiched in the axial direction (symmetrically in the axial direction of the first coil L1), The feedback coil L6 is sandwiched between the first coil L1 and the fifth coil L5 in the axial direction and is wound between the protrusions 14a and 14b. The second coil L 2 is wound while being biased toward the protrusion 25 a between the protrusions 25 a and 25 b provided at both ends of the second core 25.
[0084]
The point here is that the differentially connected fourth and fifth coils L4 and L5 are magnetically loosely coupled to the first coil L1, and the degree of magnetic coupling between the second coil L2 and the fourth coil L4. However, it is comprised so that it may become larger than the magnetic coupling degree of the 2nd coil L2 and the 5th coil L5.
[0085]
(Embodiment 3)
The contactless power feeding system of the present embodiment shown in FIG. 13 is substantially the same as the contactless power feeding system shown in FIG. 2 of the first embodiment, but the configuration of the signal generator 24 is different, and is connected in series with the third coil L3. A choke coil L7 is connected, and a resonance capacitor C8 is connected in parallel to a series circuit of a third coil L3 and a choke coil L7.
[0086]
In this embodiment, the inductance value is increased by connecting the choke coil L7 in series with the third coil L3. When the number of turns of the third coil L3 cannot be increased due to space or the like, Since the inductance value is small, there is a case where the resonance current becomes too large and the heat loss cannot be ignored. In such a case, the resonance current can be reduced by configuring the resonance circuit by connecting the choke coil L7 having a large inductance value in series to the third coil L3.
[0087]
In the first, second, and third embodiments, “the oscillation stop or suppression control for energy saving control and metal foreign matter overheating countermeasure when the power supply side is alone” and “continuous power supply when the correct load is mounted” "Control" and "Power transmission control based on demand from the load side" are targeted, but "Oscillation is stopped or suppressed for energy saving control and countermeasures against metal foreign matter overheating when the power supply side is alone. The present invention can also be applied to a case where only two controls of “control” and “continuous power supply control when a correct load is attached” are targeted.
[0088]
【The invention's effect】
The invention according to claim 1 is a high-frequency inverter circuit that outputs high-frequency power, an inverter control circuit that controls the high-frequency inverter circuit, and a first coil that is supplied with high-frequency power from the high-frequency inverter circuit and performs power supply by magnetic coupling And a signal receiving circuit having an input signal coil, wherein the inverter control circuit controls the high-frequency inverter circuit based on a signal detected by the input signal coil, and
A second coil disposed opposite to the first coil and receiving power by magnetic coupling; a power conversion circuit for converting the output of the second coil into predetermined electrical energy; and an oscillation frequency of the high-frequency inverter circuit A signal generation device that generates a signal having a frequency of a harmonic component, a secondary-side control circuit that controls a signal generated by the signal generation device, and a load that is supplied with electrical energy from the power conversion circuit It consists of a contact power receiving device,
The first coil and the second coil have a transformer structure that is detachable from each other, and the input signal coil receives a signal that detects the presence or absence of the non-contact power receiving device and a signal that is generated by the signal generating device. Since the detected signal is output, the power supply control is performed by identifying the power supply status using a signal having the same frequency as the harmonic frequency of the power frequency, so that the circuit configuration and the transformer structure are simplified. It is possible to reduce the size of the system and reduce the cost. Therefore, there is an effect that it is possible to identify the situation on the power receiving side and perform power supply control, and to provide a non-contact power transmission device having a simple structure.
[0089]
According to a second aspect of the present invention, in the first aspect, the signal generation device is a resonance circuit including a third coil and a capacitor and having a resonance frequency of the harmonic component, and the contactless power supply device. When the non-contact power receiving device is roughly disposed opposite to the non-contact power receiving device, the harmonics extracted from the magnetic field, magnetic flux in the non-contact power feeding device and the non-contact power receiving device, or the voltage or current information in the non-contact power receiving device. A frequency signal of the component is generated, the input signal coil detects a signal of the frequency of the harmonic component, and the inverter control circuit controls the high frequency inverter circuit based on the signal detected by the input signal coil. Since power supply control from the non-contact power supply device to the non-contact power reception device is performed, a signal having a harmonic component frequency is generated using a resonance circuit in the signal generation device. There is an effect that can be.
[0090]
According to a third aspect of the present invention, in the first or second aspect, the frequency of the harmonic component is a frequency of a harmonic component that is an odd multiple of the oscillation frequency of the high-frequency inverter circuit. An apparatus that generates a waveform has an effect of easily generating a signal having a frequency of a harmonic component.
[0091]
According to a fourth aspect of the present invention, in the third aspect, since the odd harmonic component is a third harmonic component, a circuit for half-wave rectifying the output of the second coil and a constant voltage load are provided. With the configuration, there is an effect that a signal having a harmonic component frequency can be easily generated.
[0092]
According to a fifth aspect of the present invention, in any one of the first to fourth aspects, the power conversion circuit includes a circuit for half-wave rectifying the output of the second coil, so that the cost can be reduced. .
[0093]
According to a sixth aspect of the present invention, in any one of the first to fifth aspects, the signal receiving circuit includes a resonant capacitor connected to the input signal coil, and resonates at the frequency of the harmonic component. There is an effect that can be performed.
[0094]
A seventh aspect of the present invention is that, in any one of the first to sixth aspects, the input signal coil includes a fourth coil and a fifth coil that are differentially connected. There is an effect that the signal detected in step 1 can be differentially output and enlarged.
[0095]
The invention according to claim 8 is the signal according to any one of claims 1 to 7, wherein the non-contact power receiving device is disposed substantially opposite to the non-contact power feeding device, and the non-contact power receiving device requests power feeding. Since the output of the generating device is increased, there is an effect that the situation on the power receiving side can be identified.
[0096]
A ninth aspect of the present invention provides the method according to any one of the first to eighth aspects, wherein the non-contact power receiving device is disposed substantially opposite to the non-contact power feeding device, and the non-contact power receiving device rejects power feeding. Since the secondary control circuit reduces the output of the signal generator, the same effect as that of claim 8 can be obtained.
[0097]
A tenth aspect of the present invention is that in any one of the first to ninth aspects, the high-frequency inverter circuit performs intermittent oscillation when the non-contact power feeding device is present alone. There is an effect that it can be planned.
[0098]
An eleventh aspect of the present invention is that in any one of the second to tenth aspects, the high-frequency inverter circuit includes an oscillation switching element and a self-excitation control switching element that connects a control terminal of the oscillation switching element to a ground level. A self-excited oscillation, and the inverter control circuit intermittently stops the oscillation of the switching element for oscillation by intermittently stopping the oscillation of the switching element for self-excitation, and the input signal coil An oscillation switching switching element that stops the intermittent stop operation of the forced stop circuit by being turned on with an output of
When the contactless power feeding device is single, the output voltage of the input signal coil is maintained at a voltage at which the oscillation switching switching element is turned off, and the forced stop circuit operates to oscillate the oscillation switching element. Is controlled to intermittent oscillation,
When the non-contact power receiving device is disposed substantially opposite to the non-contact power feeding device, and the non-contact power receiving device requests power feeding, the signal generating device is configured such that the oscillation operation of the oscillation switching element is intermittent oscillation. The third coil is excited by a signal of the frequency of the harmonic component extracted from the magnetic field or magnetic flux in the non-contact power feeding device and the non-contact power receiving device generated during the period, or the voltage or current information in the non-contact power receiving device. The output voltage of the input signal coil, which is arranged roughly opposite to the third coil and detects the magnetic flux generated in the third coil, is a voltage at which the oscillation switching switching element is turned on, and the forced stop The circuit stops operating and controls the oscillation operation of the oscillation switching element to continuous oscillation,
When the non-contact power receiving device is disposed substantially opposite to the non-contact power feeding device, and the non-contact power receiving device rejects power feeding, the signal generator reduces the frequency signal of the harmonic component and 3 is suppressed, the output voltage of the input signal coil becomes a voltage at which the oscillation switching element is turned off, and the forced stop circuit operates to intermittently oscillate the oscillation operation of the oscillation switching element. Therefore, there is an effect that it is possible to switch between continuous oscillation and intermittent oscillation according to the identified situation on the power receiving side by using a self-excited control inverter in the non-contact power feeding device.
[0099]
A twelfth aspect of the present invention is the contactless power receiving device according to any one of the second to eleventh aspects, further comprising an auxiliary switching element that short-circuits or opens at least a part of a resonance circuit including a third coil and a capacitor. When the non-contact power receiving device is disposed substantially opposite to the non-contact power feeding device and the non-contact power receiving device rejects power feeding, the secondary control circuit operates the auxiliary switching element to By changing at least one of the frequency, amplitude, and waveform of the signal generated by the resonance circuit of the generator with respect to the frequency, amplitude, and waveform when power supply is required, the input signal coil is changed by the signal generator. The generated signal is detected, and the inverter control circuit controls the high-frequency inverter circuit based on the signal detected by the input signal coil, thereby Since the power supply to the non-contact power receiving device is reduced, the signal generated by the signal generating device is changed by turning on / off the auxiliary switching element, and the power receiving control is performed by identifying the situation on the power receiving side. There is an effect that can be.
[0100]
The invention of claim 13 is the contactless power receiving device according to any one of claims 2 to 11, wherein the contactless power receiving device includes an auxiliary switching element that short-circuits or opens at least a part of an internal circuit other than the signal generator. When the non-contact power receiving device is generally disposed opposite to the device, and the non-contact power receiving device rejects power feeding, the secondary control circuit operates the auxiliary switching element to The signal generator generates the input signal coil by changing at least one of the frequency, amplitude, and waveform of the signal generated by the resonance circuit with respect to the frequency, amplitude, and waveform when power supply is required. Detecting the signal, the inverter control circuit controls the high-frequency inverter circuit based on the signal detected by the input signal coil, and Since reducing the power supply to the contact power receiving apparatus, the same effects as claim 12.
[0101]
According to a fourteenth aspect of the present invention, in the thirteenth aspect, the non-contact power receiving device includes an auxiliary coil in which at least a part of the magnetic flux generated by the first coil is linked, and an auxiliary switching element that short-circuits or opens the auxiliary coil. When the non-contact power receiving device is generally disposed opposite to the non-contact power feeding device, and the non-contact power receiving device rejects power feeding, the secondary side control circuit operates the auxiliary switching element. Thus, since at least one of the frequency and amplitude of the signal generated by the resonance circuit of the signal generating device is made smaller than the frequency and amplitude when power supply is required, the same effect as in claim 12 can be obtained. .
[0102]
A fifteenth aspect of the present invention is the signal generator according to the twelfth aspect, wherein the signal generating device includes a resonance circuit in which a third coil and a capacitor are connected in parallel, and a series circuit of a diode and an auxiliary switching element between both ends of the parallel circuit. And when the non-contact power receiving device rejects power feeding, the secondary control circuit turns on the auxiliary switching element. Since the excitation of the third coil is suppressed, the same effect as that of claim 12 is obtained.
[0103]
According to a sixteenth aspect of the present invention, in the thirteenth aspect, the non-contact power receiving device includes an auxiliary switching element that short-circuits or opens the second coil, and the non-contact power receiving device is substantially opposed to the non-contact power feeding device. When the non-contact power receiving apparatus rejects power feeding, the secondary control circuit operates the auxiliary switching element, and out of the frequency and amplitude of the signal generated by the resonance circuit of the signal generating apparatus. Since at least one is made smaller than the frequency and amplitude when power supply is required, the same effect as in the twelfth aspect can be obtained.
[0104]
According to a seventeenth aspect of the present invention, in any one of the twelfth to sixteenth aspects, since the auxiliary switching element is an element that conducts in one direction, there is an effect that the auxiliary switching element can be easily selected.
[0105]
The invention of claim 18 includes the capacitor connected in series to the auxiliary switching element according to any one of claims 12 to 17, so that the frequency of the signal generated by the signal generator can be increased by turning on and off the auxiliary switching element. The effect is that the power receiving side can be more reliably discriminated by changing greatly.
[0106]
The nineteenth aspect of the present invention has the same effect as the eighteenth aspect of the present invention, because it includes a capacitor connected in parallel to the auxiliary switching element.
[0107]
According to a twentieth aspect of the present invention, in any one of the first to nineteenth aspects, since the magnetic coupling between the second coil and the third coil is a loose coupling, it is not affected by the coil current of the second coil. The third coil has an effect that it can generate magnetic flux.
[0108]
According to a twenty-first aspect of the present invention, in any one of the first to twentieth aspects, since the output portion of the input signal coil includes a filter that detects the same frequency band as the frequency of the harmonic component, reliable signal detection is performed. There is an effect that can be. .
[0109]
According to a twenty-second aspect of the present invention, in any one of the first to twenty-first aspects, the high frequency inverter circuit applies a sinusoidal alternating voltage between both ends of the first coil. There is an effect that can be used.
[0110]
According to a twenty-third aspect of the present invention, in any one of the first to twenty-second aspects, the high frequency inverter circuit includes a switching element for oscillation and a resonant capacitor connected in parallel to the switching element for oscillation or the first coil. Since it is a voltage resonance inverter, there exists an effect that a sinusoidal alternating voltage can be applied between the both ends of a 1st coil.
[0111]
According to a twenty-fourth aspect of the present invention, in any one of the seventh to twenty-third aspects, the magnetic coupling between the fourth and fifth coils and the first coil, which constitute the input signal coil, is loosely coupled. The degree of magnetic coupling between any one of the fourth coil and the fifth coil and the third coil is the magnetic coupling between the other of the fourth coil and the fifth coil and the third coil. Since this is larger than the degree, there is an effect that a differential output between the fourth coil and the fifth coil can be obtained.
[0112]
According to a twenty-fifth aspect of the present invention, in the twenty-fourth aspect, the fourth and fifth coils are arranged symmetrically with respect to the first coil, and the third coil is composed of the fourth coil and the fifth coil. Since it is arranged to face either one of them, the influence of the magnetic flux generated in the first coil on the differential output between the fourth coil and the fifth coil can be reduced, and the third There is an effect that the magnetic coupling degree between the coil and the fourth coil can be made different from the magnetic coupling degree between the third coil and the fifth coil.
[0113]
According to a twenty-sixth aspect of the present invention, in the first aspect, when power is supplied from the non-contact power supply device to the non-contact power reception device, the both-end voltage and coil current of the second coil have a distorted waveform, and the signal generation Since the apparatus generates a signal using a harmonic component included in the voltage across the second coil and the coil current as a generation source, there is an effect that the signal generation apparatus can be easily configured.
[0114]
According to a twenty-seventh aspect of the present invention, in the twenty-sixth aspect, the magnetic coupling between the differentially connected fourth and fifth coils constituting the input signal coil and the first coil is a loose coupling, and the fourth coil The degree of magnetic coupling between one of the fifth coils and the second coil is greater than the degree of magnetic coupling between the other of the fourth coil and the fifth coil and the second coil. There is an effect that a differential output by the magnetic flux generated by the second coil can be obtained.
[0115]
The invention of claim 28 is the signal generator according to any one of claims 1 to 27, wherein the signal generator includes a signal generating means by a resonance circuit of a third coil and a capacitor having a resonance frequency of the harmonic component frequency, 2 is provided with a signal generating means for generating a signal using a harmonic component contained in the voltage between both ends of the coil 2 and the coil current as a generation source. There is an effect that can be.
[0116]
A 29th aspect of the present invention is that in any one of the first to 25th and 28th aspects, the signal generator includes an inductor connected in series to the third coil. Therefore, even if the inductance of the third coil is small, the signal generator There is an effect that the loss can be reduced.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a block configuration according to a first embodiment of the present invention.
FIG. 2 is a diagram showing a first circuit configuration of the above.
FIG. 3 is a diagram showing waveforms at various parts from start-up to continuous oscillation.
FIG. 4 is a diagram showing waveforms at various parts from start-up to intermittent oscillation according to the above.
FIG. 5 is a side sectional view showing an example of the structure of the above-described separation / detachment type transformer.
FIG. 6 is a side sectional view showing a primary side of a structural example of the above-described separation / detachment type transformer.
FIG. 7 is a diagram showing a second circuit configuration of the above.
FIG. 8 is a diagram showing a third circuit configuration of the above.
FIG. 9 is a diagram showing a fourth circuit configuration as above;
FIG. 10 is a diagram showing a voltage waveform across a second coil according to the second embodiment of the present invention.
FIG. 11 is a diagram showing an equivalent circuit on the secondary side of the above.
FIG. 12 is a side cross-sectional view showing a structural example of the above-described separation / detachment type transformer.
FIG. 13 is a diagram showing a circuit configuration of a third embodiment of the present invention.
[Explanation of symbols]
1 Contactless power supply
2 Non-contact power receiving device
11 High frequency inverter circuit
12 Signal receiving circuit
13 Inverter control circuit
21 Power conversion circuit
23 Secondary side control circuit
24 Signal generator
30 load
L1 to L5 1st to 5th coils
Ls Input signal coil
C4, C8 resonant capacitor
S2 switch

Claims

A high-frequency inverter circuit that outputs high-frequency power; an inverter control circuit that controls the high-frequency inverter circuit; a first coil that is supplied with high-frequency power from the high-frequency inverter circuit and that supplies power by magnetic coupling; and an input signal coil A non-contact power feeding device including a signal receiving circuit, wherein the inverter control circuit controls the high-frequency inverter circuit based on a signal detected by the input signal coil;
A second coil disposed opposite to the first coil and receiving power by magnetic coupling; a power conversion circuit for converting the output of the second coil into predetermined electrical energy; and an oscillation frequency of the high-frequency inverter circuit A signal generation device that generates a signal having a frequency of a harmonic component, a secondary-side control circuit that controls a signal generated by the signal generation device, and a load that is supplied with electrical energy from the power conversion circuit It consists of a contact power receiving device,
The first coil and the second coil have a transformer structure that is detachable from each other, and the input signal coil receives a signal that detects the presence or absence of the non-contact power receiving device and a signal that is generated by the signal generating device. A non-contact power supply system that outputs a detected signal.

The signal generation device is a resonance circuit including a third coil and a capacitor and having a resonance frequency of the harmonic component frequency, and the contactless power receiving device is roughly disposed opposite to the contactless power feeding device. And generating the signal of the frequency of the harmonic component extracted from the magnetic field, magnetic flux, or voltage or current information in the non-contact power receiving device in the non-contact power feeding device and the non-contact power receiving device, The coil detects a signal having a frequency of the harmonic component, and the inverter control circuit controls the high-frequency inverter circuit based on the signal detected by the input signal coil, so that the contactless power receiving device and the contactless power receiving device. The contactless power feeding system according to claim 1, wherein power feeding control is performed.

The contactless power feeding system according to claim 1, wherein the frequency of the harmonic component is a frequency of a harmonic component that is an odd multiple of the oscillation frequency of the high-frequency inverter circuit.

The contactless power feeding system according to claim 3, wherein the odd harmonic component is a third harmonic component.

The non-contact power feeding system according to claim 1, wherein the power conversion circuit includes a circuit that rectifies the output of the second coil by half-wave.

6. The non-contact power feeding system according to claim 1, wherein the signal receiving circuit includes a resonance capacitor connected to the input signal coil, and resonates at a frequency of the harmonic component.

The contactless power supply system according to claim 1, wherein the input signal coil includes a fourth coil and a fifth coil that are differentially connected.

The output of the signal generator increases when the non-contact power receiving device is disposed substantially opposite to the non-contact power feeding device, and the non-contact power receiving device requests power feeding. 7. The non-contact power supply system according to any one of 7.

The secondary control circuit reduces the output of the signal generating device when the contactless power receiving device is arranged substantially opposite to the contactless power feeding device and the contactless power receiving device rejects power feeding. The non-contact power feeding system according to claim 1, wherein the system is a non-contact power feeding system.

The non-contact power feeding system according to claim 1, wherein the high-frequency inverter circuit performs intermittent oscillation when the non-contact power feeding device is present alone.

The high-frequency inverter circuit includes a switching element for oscillation and a switching element for self-excitation control that connects a control terminal of the oscillation switching element to a ground level, and performs self-excited oscillation. A forced stop circuit for intermittently stopping the oscillation operation of the oscillation switching element by intermittently stopping the oscillation of the control switching element, and an intermittent stop operation of the forced stop circuit by turning on at the output of the input signal coil A switching element for switching oscillation to be stopped,
When the contactless power feeding device is single, the output voltage of the input signal coil is maintained at a voltage at which the oscillation switching switching element is turned off, and the forced stop circuit operates to oscillate the oscillation switching element. Is controlled to intermittent oscillation,
When the non-contact power receiving device is disposed substantially opposite to the non-contact power feeding device, and the non-contact power receiving device requests power feeding, the signal generating device is configured such that the oscillation operation of the oscillation switching element is intermittent oscillation. The third coil is excited by a signal of the frequency of the harmonic component extracted from the magnetic field or magnetic flux in the non-contact power feeding device and the non-contact power receiving device generated during the period, or the voltage or current information in the non-contact power receiving device. The output voltage of the input signal coil, which is arranged roughly opposite to the third coil and detects the magnetic flux generated in the third coil, is a voltage at which the oscillation switching switching element is turned on, and the forced stop The circuit stops operating and controls the oscillation operation of the oscillation switching element to continuous oscillation,
When the non-contact power receiving device is disposed substantially opposite to the non-contact power feeding device, and the non-contact power receiving device rejects power feeding, the signal generator reduces the frequency signal of the harmonic component and 3 is suppressed, the output voltage of the input signal coil becomes a voltage at which the oscillation switching element is turned off, and the forced stop circuit operates to intermittently oscillate the oscillation operation of the oscillation switching element. The non-contact power feeding system according to claim 2, wherein the non-contact power feeding system is controlled.

The non-contact power receiving device includes an auxiliary switching element that short-circuits or opens at least a part of a resonance circuit including a third coil and a capacitor, and the non-contact power receiving device is roughly disposed opposite to the non-contact power feeding device. When the non-contact power receiving apparatus rejects power feeding, the secondary side control circuit operates the auxiliary switching element to generate the frequency, amplitude, and waveform of the signal generated by the resonance circuit of the signal generating apparatus. The input signal coil detects a signal generated by the signal generator by changing at least one of the frequency, amplitude, and waveform when power supply is required, and the inverter control circuit detects the input signal coil. The high-frequency inverter circuit is controlled based on the signal detected by the non-contact power feeding device to reduce power feeding from the non-contact power feeding device to the non-contact power receiving device. Non-contact power supply system in accordance with claim 2 to 11.

The non-contact power receiving device includes an auxiliary switching element that short-circuits or opens at least a part of an internal circuit other than the signal generator, and the non-contact power receiving device is roughly disposed opposite to the non-contact power feeding device, When the non-contact power receiving apparatus rejects power feeding, the secondary side control circuit operates the auxiliary switching element, and at least one of the frequency, amplitude, and waveform of the signal generated by the resonance circuit of the signal generating apparatus The input signal coil detects the signal generated by the signal generator, and the inverter control circuit detects the input signal coil. The power supply from the non-contact power supply device to the non-contact power reception device is reduced by controlling the high-frequency inverter circuit based on the received signal. 2 to 11 non-contact power supply system according to any one.

The non-contact power receiving device includes an auxiliary coil in which at least a part of the magnetic flux generated by the first coil is linked, and an auxiliary switching element that short-circuits or opens the auxiliary coil, and the non-contact power feeding device includes the non-contact power receiving device. When the contact power receiving device is roughly arranged oppositely and the non-contact power receiving device rejects power feeding, the secondary control circuit operates the auxiliary switching element to generate a resonance circuit of the signal generating device. The contactless power feeding system according to claim 13, wherein at least one of a frequency and an amplitude of a signal to be transmitted is made smaller than a frequency and an amplitude when power feeding is required.

The signal generator includes a resonance circuit in which a third coil and a capacitor are connected in parallel, and includes a series circuit of a diode and an auxiliary switching element between both ends of the parallel circuit, and the contactless power feeding device includes the contactless power supply. When the power receiving device is roughly arranged oppositely and the non-contact power receiving device rejects power feeding, the secondary control circuit turns on the auxiliary switching element to suppress excitation of the third coil. The non-contact electric power feeding system according to claim 12 characterized by things.

The non-contact power receiving device includes an auxiliary switching element that short-circuits or opens the second coil, the non-contact power receiving device is roughly disposed opposite to the non-contact power feeding device, and the non-contact power receiving device rejects power feeding. In the case where the secondary side control circuit operates the auxiliary switching element, at least one of the frequency and the amplitude of the signal generated by the resonance circuit of the signal generator needs to be fed. The contactless power feeding system according to claim 13, wherein the contactless power feeding system is reduced with respect to frequency and amplitude.

The non-contact power feeding system according to claim 12, wherein the auxiliary switching element is an element that conducts in one direction.

The contactless power feeding system according to claim 12, further comprising a capacitor connected in series to the auxiliary switching element.

The contactless power feeding system according to claim 12, further comprising a capacitor connected in parallel to the auxiliary switching element.

The contactless power feeding system according to claim 1, wherein the magnetic coupling between the second coil and the third coil is loose coupling.

21. The non-contact power feeding system according to claim 1, further comprising a filter that detects a frequency band that is the same as a frequency of the harmonic component at an output portion of the input signal coil.

The non-contact power feeding system according to any one of claims 1 to 21, wherein the high-frequency inverter circuit applies a sinusoidal alternating voltage between both ends of the first coil.

23. The one-way voltage resonance inverter comprising the oscillation switching element and a resonance capacitor connected in parallel to the oscillation switching element or the first coil. Or a contactless power supply system.

The magnetic coupling between the fourth and fifth coils and the first coil which are differentially connected to constitute the input signal coil is loosely coupled, and either one of the fourth coil or the fifth coil and the first coil are coupled with each other. 24. The degree of magnetic coupling with the third coil is greater than the degree of magnetic coupling between the other one of the fourth coil and the fifth coil and the third coil. Contactless power supply system.

The fourth and fifth coils are arranged at symmetrical positions with respect to the first coil, and the third coil is arranged to face either one of the fourth coil and the fifth coil. The non-contact power feeding system according to claim 24.

When power is supplied from the non-contact power supply device to the non-contact power receiving device, the both-end voltage and coil current of the second coil have a distorted waveform, and the signal generator has both-end voltage and coil of the second coil. 2. The non-contact power feeding system according to claim 1, wherein a signal having a harmonic component included in the current as a source is generated.

The magnetic coupling between the fourth and fifth coils and the first coil which are differentially connected to constitute the input signal coil is loosely coupled, and either one of the fourth coil or the fifth coil and the first coil are coupled with each other. 27. The non-contact power feeding according to claim 26, wherein the degree of magnetic coupling with the second coil is greater than the degree of magnetic coupling between the other one of the fourth coil and the fifth coil and the second coil. system.

The signal generator is configured to generate a harmonic component included in a signal generating means by a resonance circuit of a third coil and a capacitor having a resonance frequency of the harmonic component frequency, a voltage across the second coil, and a coil current. 28. The non-contact power feeding system according to claim 1, further comprising signal generating means for generating a signal as a generation source.

29. The non-contact power feeding system according to claim 1, wherein the signal generator includes an inductor connected in series to a third coil.