JP5624494B2 - Non-contact power transmission system - Google Patents

Description

  The present invention relates to a contactless power transmission system.

  Conventionally, for example, when a sensor that detects a magnetic field intensity in the vicinity of a power transmission coil that transmits power to a plurality of power receiving coils and a control unit that controls a drive frequency of an AC power supply that supplies power to the power transmission coil is changed and the drive frequency is changed There is known a power transmission device that acquires a frequency distribution of power supply efficiency from a change in output of the sensor and drives an AC power source at a drive frequency with the highest power supply efficiency (see, for example, Patent Document 1).

JP 2010-239838 A

By the way, in the power transmission device according to the above-described prior art, when the drive frequency with the highest power supply efficiency is different for the plurality of power receiving coils, there is a possibility that the power supply efficiency for the whole of the plurality of power receiving coils cannot be improved. .
For example, in resonance type power transmission in which electric power is transmitted by resonance between a magnetic field and an electric field between a power receiving coil and a power transmitting coil, as shown in FIGS. 8A to 8C, for example, the maximum efficiency at which the received power is maximized The value of the frequency changes according to the distance (Gap) between the power receiving coil and the power transmitting coil.
For this reason, simply selecting one specific drive frequency causes a problem that the power supply efficiency cannot be improved for the entire plurality of power receiving coils having different distances (Gap) to the power transmitting coil.

  The present invention has been made in view of the above circumstances, and a non-contact power transmission system capable of preventing a decrease in power receiving efficiency of each power receiving coil even when the maximum efficiency frequencies of a plurality of power receiving coils are different. The purpose is to provide.

In order to solve the above-described problems and achieve the object, the non-contact power transmission system according to the first aspect of the present invention (for example, the non-contact power transmission system 10 in the embodiment) uses AC power having a predetermined waveform. AC power output means for outputting (for example, AC power supply 41, power distribution load coefficient calculation unit 43, basic waveform generation circuit 44 and amplifier 45 in the embodiment) and the AC power output by the AC power output means. A non-contact power transmission system including a power transmission coil (for example, power transmission coil 46 in the embodiment) that transmits power to a plurality of power reception coils (for example, the power reception coil 24 in the embodiment) by a resonance phenomenon, Frequency acquisition means (for example, in the embodiment) for acquiring the maximum efficiency frequency at which the power reception efficiency of each of the plurality of power reception coils is maximized with respect to the power reception coil Comprising a vibration frequency detector 29), the AC power output unit, as the AC power of the predetermined waveform, and outputs the AC power obtained by superimposing the maximum efficiency frequency of the waveform of each of the plurality of power receiving coils, The AC power output means sets a peak value of the waveform of the maximum efficiency frequency of each of the plurality of power receiving coils based on a predetermined power distribution load coefficient .

Furthermore, the non-contact power transmission system according to the second aspect of the present invention includes a power storage unit (for example, the battery 21 in the embodiment) connected to each of the plurality of power receiving coils, and a remaining capacity of the power storage unit. A remaining capacity acquisition means for acquiring (for example, a remaining capacity detector 27 in the embodiment), wherein the AC power output means calculates a peak value of the waveform of the maximum efficiency frequency of each of the plurality of power receiving coils, It is set according to the remaining capacity of the power storage means.

Furthermore, the non-contact power transmission system according to the third aspect of the present invention is an acquisition unit (for example, an implementation unit) that acquires at least a request level or a burden cost of a user who uses a power receiving device including each of the plurality of power receiving coils. The AC power output means sets the peak value of the waveform of the maximum efficiency frequency of each of the plurality of power receiving coils according to at least the required degree or the burden cost.

The non-contact power transmission system according to the fourth aspect of the present invention (for example, the non-contact power transmission system 10 in the embodiment) is an AC power output unit that outputs AC power having a predetermined waveform (for example, in the embodiment). The AC power output 41, the power distribution load coefficient calculation unit 43, the basic waveform generation circuit 44, and the amplifier 45) and the AC power output by the AC power output means are subjected to a resonance phenomenon to generate a plurality of power receiving coils (for example, in the embodiment). A non-contact power transmission system including a power transmission coil (for example, power transmission coil 46 in the embodiment) that transmits power to the power reception coil 24), and each of the plurality of power reception coils with respect to the plurality of power reception coils. Frequency acquisition means (for example, the resonance frequency detector 29 in the embodiment) for acquiring the maximum efficiency frequency at which the power reception efficiency of the plurality of power reception efficiency is maximum, Comprising acquisition means for acquiring at least demanding or pocket expenses user using the power receiving device comprising a coil (e.g., the input device 28 in the embodiment) and, wherein the AC power output means of the predetermined waveform As AC power, output AC power obtained by time-sharing the waveform of the maximum efficiency frequency of each of the plurality of power receiving coils, and the AC power output means is configured to output the maximum power of each of the plurality of power receiving coils. A time width in the time division of the waveform of the efficiency frequency is set according to at least the required degree or the burden cost.

Furthermore, the non-contact power transmission system according to the fifth aspect of the present invention includes a power storage means (for example, the battery 21 in the embodiment) connected to each of the plurality of power receiving coils, and a remaining capacity of the power storage means. A remaining capacity acquisition means for acquiring (for example, a remaining capacity detector 27 in the embodiment), wherein the AC power output means is the time division of the waveform of the maximum efficiency frequency of each of the plurality of power receiving coils. Is set in accordance with the remaining capacity of the power storage means.

  According to the non-contact power transmission system according to the first aspect of the present invention, the power transmission is performed from the power transmission coil to the plurality of power reception coils by the resonance phenomenon at the maximum efficiency frequency, and thus the maximum efficiency of the plurality of power reception coils. Even when the frequencies are different, it is possible to prevent a decrease in power receiving efficiency of each power receiving coil.

Furthermore , electric power can be transmitted simultaneously to a plurality of power receiving coils.

Furthermore, according to the non-contact power transmission system according to the second aspect of the present invention, power is transmitted to the plurality of power receiving coils by AC power distributed according to the remaining capacity of the power storage means connected to each of the plurality of power receiving coils. be able to.

Furthermore, according to the non-contact power transmission system according to the third aspect of the present invention, the power is distributed to the plurality of power receiving coils in accordance with at least the degree of demand or burden cost of the user who uses the power receiving device including each of the power receiving coils. Power transmission can be performed using AC power.

According to the non-contact power transmission system according to the fourth aspect of the present invention, power is transmitted from the power transmission coil to the plurality of power reception coils by the resonance phenomenon at the maximum efficiency frequency, and thus the maximum efficiency of the plurality of power reception coils. Even when the frequencies are different, it is possible to prevent a decrease in power receiving efficiency of each power receiving coil. Furthermore, it is possible to sequentially transmit power to the plurality of power receiving coils in accordance with the time division arrangement. Furthermore, it is possible to perform power transmission with respect to a plurality of power receiving coils by AC power that is time-divided according to at least the degree of demand or burden cost of a user who uses the power receiving device including each of the power receiving coils.

Furthermore, according to the non-contact power transmission system according to the fifth aspect of the present invention, power is transmitted to the plurality of power receiving coils by AC power that is time-divided according to the remaining capacity of the power storage means connected to each of the plurality of power receiving coils. Can be done.

It is a lineblock diagram of the non-contact electric power transmission system concerning an embodiment of the invention. It is a partial block diagram of the non-contact electric power transmission system which concerns on embodiment of this invention. It is a figure which shows the example of the peak value of the waveform superimposed by the basic waveform generation circuit of the non-contact electric power transmission system which concerns on embodiment of this invention. It is a figure which shows the example of the correspondence of the gain and frequency according to the Q value of the power transmission coil of the non-contact electric power transmission system which concerns on embodiment of this invention, and a receiving coil. It is a figure which shows the timing of operation | movement of the non-contact electric power transmission system which concerns on embodiment of this invention. It is a flowchart of operation | movement of the non-contact electric power transmission system which concerns on embodiment of this invention. It is a figure which shows the timing of operation | movement of the non-contact electric power transmission system which concerns on the modification of embodiment of this invention. It is a figure which shows the example of the value of the maximum efficiency frequency which changes according to the distance (Gap) between a receiving coil and a power transmission coil in resonance type electric power transmission.

Hereinafter, a non-contact power transmission system according to an embodiment of the present invention will be described with reference to the accompanying drawings.
The non-contact power transmission system 10 according to the present embodiment includes, for example, as shown in FIG. 1, a plurality of vehicles 11 (that is, vehicles (1),..., Vehicles (n) shown in FIG. 1), a charging station 12, It is configured with.

  This non-contact power transmission system 10 uses a resonance-type non-contact power transmission method using a resonance phenomenon to transmit power output from the charging station 12 to a plurality of vehicles 11 (that is, vehicles (1), ..., the vehicle (n)) can be transmitted in a non-contact manner, and the battery 21 mounted on each vehicle 11 can be charged.

  Each vehicle 11 (vehicle (k); k = 1,..., N; n is an arbitrary natural number) includes, for example, a battery 21, a vehicle driving unit 22, a power receiving antenna 23 and a power receiving coil 24, and a rectifier circuit 25. The DC / DC converter 26, the remaining capacity detector 27, the input device 28, the resonance frequency detector 29, the required parameter calculation unit 30, and the vehicle wireless communication unit 31 are configured.

The vehicle drive unit 22 includes, for example, a motor (not shown) such as a three-phase DC brushless motor that generates a driving force for driving the vehicle 11 and a motor control device that controls driving and regenerative operation of the motor. ing.
The motor control device includes, for example, a transistor switching element, and includes an inverter that exchanges electrical energy with the battery 21.

The power receiving antenna 23 and the power receiving coil 24 receive power transmitted from the power transmitting coil 46 and the power transmitting antenna 47 of the charging station 12 by a resonance type non-contact power transmission method.
In the resonance-type non-contact power transmission method, a magnetic field between a resonator (not shown) on the vehicle 11 side including the power receiving coil 24 and a resonator (not shown) on the charging station 12 side including the power transmission coil 46 and Electric power is transmitted by electric field resonance.

  That is, the power transmission coil 46 that is a primary coil is disposed close to the power transmission antenna 47 of the charging station 12, and the power reception coil 24 that is a secondary coil is disposed close to the power reception antenna 23 of the vehicle 11. ing.

When a primary current is passed through the power transmission coil 46, an induced current flows through the power transmission antenna 47 by electromagnetic induction. The power transmission antenna 47 further includes inductance and floating of the resonator on the charging station 12 side including the power transmission coil 46. Resonates at a resonance frequency according to the capacity.
Accordingly, the power receiving antenna 23 provided in the vicinity of the power transmitting antenna 47 resonates at the resonance frequency, a secondary current flows through the power receiving antenna 23, and further, the power receiving coil 24 adjacent to the power receiving antenna 23 by electromagnetic induction has 2 Next current flows.

The rectifier circuit 25 converts AC power output from the power receiving coil 24 into DC power.
The DC / DC converter 26 converts direct current power output from the rectifier circuit 25 into direct current, for example, according to an allowable voltage of the battery 21 or the like.
Note that the DC / DC converter 26 may be omitted.

The remaining capacity detector 27 detects the remaining capacity SOC of the battery 21 by, for example, a current integration method.
In this current integration method, the remaining capacity detector 27 calculates the integrated charge amount and integrated discharge amount by integrating the charging current and discharge current of the battery 21 every predetermined period, and calculates the integrated charge amount and integrated discharge amount. The current remaining capacity SOC is calculated by adding or subtracting to the initial state or the remaining capacity immediately before the start of charge / discharge.

  Furthermore, the remaining capacity detector 27 performs a predetermined correction process on the remaining capacity SOC calculated by the current integration method, for example, for an internal resistance that changes according to the temperature of the battery 21 or a predetermined correction process according to the voltage between the terminals. And output the processing result signal.

The input device 28 outputs a signal of information related to the driver's intention to charge the battery 21 by power transmission from the charging station 12 in response to an input operation by the driver.
Information on the driver's intention includes, for example, a request level EM indicating the degree of desire of the driver to perform charging by a numerical value and the like, and a burden cost CO indicating the degree of burden cost required for the charge permitted by the driver by a numerical value and the like Etc.

The resonance frequency detector 29 is a resonance frequency (maximum efficiency frequency) ω _k (k = 1,..., N; n is an arbitrary natural number) at which the power receiving efficiency of the power receiving coil 24 is maximized with respect to power transmission from the charging station 12. Is detected and a detection result signal is output.

For example, the resonance frequency detector 29 has a resonance frequency (maximum power reception efficiency of the power reception coil 24 when the frequency of power transmission from the charging station 12 is changed by sweeping within a predetermined frequency range in a later-described sweep period Ta. Maximum efficiency frequency) ω _k (k = 1,..., N; n is an arbitrary natural number) is detected.

For example, as shown in FIG. 2, the request parameter calculation unit 30 is based on the remaining capacity SOC output from the remaining capacity detector 27, the required degree EM and the burden cost CO output from the input device 28, for example, A required parameter β _k (k = 1,..., N; n is an arbitrary natural number) described as shown in (1) is calculated, and a calculation result signal is output.

In the above equation (1), the required parameter β _k includes a predetermined function f (SOC) having the remaining capacity SOC as a variable, a predetermined function g (EM) having the required degree EM as a variable, and a burden cost CO. And a predetermined function h (CO) having a variable as a variable.

For example, as illustrated in FIG. 1, the vehicle wireless communication unit 31 transmits and receives various types of information through wireless communication with the wireless communication unit 22 of the charging station 12.
For example, the vehicular wireless communication unit 31 may use the maximum efficiency frequency ω _k output from the resonance frequency detector 29 and the required parameter β _k output from the required parameter calculation unit 30 (k = 1,..., N; n is an arbitrary value) (Natural number) is transmitted to the wireless communication unit 42 of the charging station 12.

The charging station 12 includes an AC power source 41, a wireless communication unit 42, a power distribution load coefficient calculation unit 43, a basic waveform generation circuit 44, an amplifier 45, a power transmission coil 46, and a power transmission antenna 47. Yes.
The charging station 12 is installed at an arbitrary place such as a road surface on which a plurality of vehicles 11,..., 11 travels or a facility (for example, a commercial facility) where the plurality of vehicles 11,. May be.

The wireless communication unit 42 transmits and receives various types of information through wireless communication with the vehicle wireless communication unit 31 of each vehicle 11.
For example, the radio communication unit 42 receives the maximum efficiency frequency ω _k and the request parameter β _k (k = 1,..., N; n is an arbitrary natural number) transmitted from the vehicle radio communication unit 41 of each vehicle 11.

For example, as shown in FIGS. 1 and 2, the power distribution load coefficient calculation unit 43 receives the request parameter β _k (k = 1,..., N; n is an arbitrary natural number) received by the wireless communication unit 42. ), For example, as shown in the following formula (2), a power distribution load coefficient α _k (k = 1,..., N; n is an arbitrary natural number) is calculated, and a calculation result signal is output.

In the above formula (2), the total sum of the power distribution load coefficients α _k (k = 1,..., N; n is an arbitrary natural number) is 1.

The basic waveform generation circuit 44 outputs the maximum efficiency frequency ω _k (k = 1,..., N; n is an arbitrary natural number) of each vehicle 11 received by the wireless communication unit 42 and the power distribution load coefficient calculation unit 43. Based on the power distribution load coefficient α _k (k = 1,..., N; n is an arbitrary natural number), for example, a carrier wave fc described as shown in the following equation (3) is calculated, and the calculation result Output a signal.

For example, as shown in FIG. 3, the carrier wave fc includes a frequency of a maximum efficiency frequency ω _k (k = 1,..., N; n is an arbitrary natural number) and a power distribution load coefficient α _k (k = 1,..., N; where n is an arbitrary natural number), a waveform obtained by superimposing a waveform having a peak value on a plurality of vehicles 11.

For example, as shown in FIG. 1, the amplifier 45 is supplied from the AC power supply 41 by a pulse width modulation (PWM) or the like according to the carrier wave fc output from the basic waveform generation circuit 44 in a power supply period Tb of a predetermined period T. The output AC power is amplified, and the AC power resulting from the amplification is output to the power transmission coil 46.
That is, the AC power output to the power transmission coil 46 is AC power including a waveform of the maximum efficiency frequency ω _k (k = 1,..., N; n is an arbitrary natural number) of the power receiving coils 24 of the plurality of vehicles 11. Thus, the AC power is obtained by superimposing the waveforms of the maximum efficiency frequencies ω _k (k = 1,..., N; n is an arbitrary natural number) of the power receiving coils 24 of the plurality of vehicles 11.

In addition, the amplifier 45 amplifies the AC power output from the AC power supply 41 by, for example, pulse width modulation (PWM) according to a predetermined carrier wave, for example, in the sweep period Ta having a predetermined cycle T. The frequency of a predetermined carrier wave is changed by sweeping within a predetermined frequency range.
As a result, the amplifier 45 outputs AC power having a frequency changed by sweeping within a predetermined frequency range to the power transmission coil 46 in the sweep period Ta of the predetermined period T.

  The power transmission coil 46 and the power transmission antenna 47 transmit power to the power receiving antenna 23 and the power receiving coil 24 of each vehicle 11 by a resonance type non-contact power transmission method.

  In general, the Q value is known as an index of the performance of power transmission. For example, as shown in FIG. 4, the Q value of the power transmission coil 46 of the charging station 12 is low so that a resonance state can be obtained at a wide frequency. The Q value of the power receiving coil 24 of each vehicle 11 may be set so as to increase the resonance state.

  The contactless charging system 10 according to the present embodiment has the above-described configuration. Next, operations of the contactless charging system 10, that is, operations of the vehicles 11 and the charging station 12 will be described.

For example, as illustrated in FIG. 5, the charging station 12 of the non-contact charging system 10 includes a predetermined period T including a sweep period Ta and a power transmission period Tb in the moving state of each vehicle 11.
Then, at each predetermined cycle T that is sequentially repeated, first, in the sweep period Ta, the frequency of the AC power transmitted to each vehicle 11 is changed by sweeping within a predetermined frequency range.

Accordingly, each vehicle 11 detects a resonance frequency (maximum efficiency frequency) ω _k (k = 1,..., N; n is an arbitrary natural number) at which the power receiving efficiency of the power receiving coil 24 is maximized, Based on the capacity SOC, the required degree EM, and the burden cost CO, the required parameter β _k (k = 1,..., N; n is an arbitrary natural number) is calculated.

The charging station 12 then determines the power distribution load coefficient α _k (k = 1,..., N; n) based on the required parameter β _k (k = 1,..., N; n is an arbitrary natural number) of each vehicle 11. An arbitrary natural number) is calculated, and further, a carrier wave based on the resonance frequency (maximum efficiency frequency) ω _k and the power distribution load coefficient α _k (k = 1,..., N; n is an arbitrary natural number) of each vehicle 11 fc is calculated.

  Next, in the power supply period Tb, the charging station 12 amplifies the AC power output from the AC power supply 41 based on the carrier wave fc calculated in the sweep period Ta, and transmits the AC power resulting from the amplification to each vehicle 11. To do.

Below, operation | movement of the non-contact charge system 10 is demonstrated.
First, for example, in step S01 shown in FIG. 6, it is determined whether there is a power transmission instruction input from the outside.
If this determination is “NO”, the flow proceeds to the end.
On the other hand, if this determination is “YES”, the flow proceeds to step S 02.
Next, in step S02, time measurement is started after the timer value t of a timer (not shown) is initialized to zero.

Next, in step S03, the maximum efficiency frequency ω _k (k = 1,..., N; n is an arbitrary natural number) of the power receiving coil 24 of each vehicle 11 is acquired.
Next, in step S04, the remaining capacity SOC, the required degree EM, and the burden cost CO of each vehicle 11 are acquired.

Next, in step S05, the required parameter β _k (k = 1,..., N; n is an arbitrary natural number) of each vehicle 11 is calculated.
Next, in step S06, the power distribution load coefficient α _k (k = 1,..., N; n is an arbitrary natural number) of each vehicle 11 is calculated.
Next, in step S07, a carrier wave fc is calculated.

Next, in step S08, the AC power output from AC power supply 41 is amplified based on carrier wave fc.
Next, in step S09, power transmission from the charging station 12 to each vehicle 11 is started.

In step S10, it is determined whether or not the timer value t has reached a predetermined period T.
When the determination result is “NO”, the determination in step S10 is repeatedly executed.
On the other hand, if this determination is “YES”, the flow proceeds to step S11.
And in step S11, power transmission is stopped and it returns to step S01 mentioned above.

As described above, according to the contactless power transmission system 10 according to the present embodiment, the maximum efficiency frequency ω _k (k = 1, from the power transmission coil 46 of the charging station 12 to the power reception coils 24 of the plurality of vehicles 11. ..., n; n is an arbitrary natural number), and power transmission is performed by a resonance phenomenon.
Thereby, even if it is a case where the maximum efficiency frequency of the receiving coil 24 of the some vehicle 11 differs from each other, the fall of the receiving efficiency of each receiving coil 24 can be prevented.
In addition, power can be transmitted to the power receiving coils 24 of the plurality of vehicles 11 simultaneously.

Furthermore, electric power can be transmitted to the power receiving coils 24 of the plurality of vehicles 11 by AC power distributed according to the remaining capacity SOC of the battery 21 of each vehicle 11.
Furthermore, electric power can be transmitted to the power receiving coils 24 of the plurality of vehicles 11 using AC power distributed according to at least the degree of demand EM and the burden cost CO of the driver of each vehicle 11.

In the above-described embodiment, the basic waveform generation circuit 44 uses the frequency of the maximum efficiency frequency ω _k (k = 1,..., N; n is an arbitrary natural number) of each vehicle 11 and the power distribution load coefficient α _k ( The carrier wave fc is calculated by superimposing a waveform having a peak value corresponding to k = 1,..., n; n is an arbitrary natural number), but is not limited to this. The carrier wave fc according to the modified example of the above-described embodiment described as shown in 4) may be calculated and a signal of the calculation result may be output.

In this modification, the basic waveform generation circuit 44 generates a plurality of waveforms having the frequency of the maximum efficiency frequency ω _k (k = 1,..., N; n is an arbitrary natural number) of each vehicle 11 and the same peak value. The carrier wave fc is calculated by time division.
Then, the basic waveform generation circuit 44 sets the time width of each waveform in time division according to the power distribution load coefficient α _k (k = 1,..., N; n is an arbitrary natural number) of each vehicle 11. .

Thereby, the AC power output from the charging station 12 to the power transmission coil 46 of each vehicle 11 is the maximum efficiency frequency ω _k (k = 1,..., N; n is an arbitrary natural number) of the power reception coils 24 of the plurality of vehicles 11. ) Obtained by arranging the waveforms of the maximum efficiency frequency ω _k (k = 1,..., N; n is an arbitrary natural number) of the receiving coils 24 of the plurality of vehicles 11 in a time-sharing manner. AC power is generated.

For example, as shown in FIG. 7, when power is transmitted from the charging station 12 to four vehicles 11 (vehicle (1),..., Vehicle (4)), the basic waveform generation circuit 44 first sets the vehicle ( A waveform having a predetermined peak value having a frequency of the maximum efficiency frequency ω _{1 with} respect to 1) is arranged with a time width (= α ₁ · Tb) corresponding to the power distribution load coefficient α ₁ from the start time t2 of the power transmission start period Tb. To do.

Next, the basic waveform generation circuit 44 generates a waveform having a predetermined peak value having a frequency of the maximum efficiency frequency ω ₂ for the vehicle (2) according to the power distribution load coefficient α ₂ from time t3 within the power transmission start period Tb. Are arranged with a time width (= α ₂ · Tb). Note that the time t3 is a time elapsed by a time width (= α ₁ · Tb) from the start time t2.

Next, the basic waveform generation circuit 44 generates a waveform having a predetermined peak value having a frequency of the maximum efficiency frequency ω ₃ for the vehicle (3) according to the power distribution load coefficient α ₃ from the time t4 within the power transmission start period Tb. The time width is set (= α ₃ · Tb). Note that the time t4 is a time elapsed by a time width (= α ₂ · Tb) from the time t3.

Next, the basic waveform generation circuit 44 applies a waveform having a predetermined peak value having a frequency of the maximum efficiency frequency ω ₄ to the vehicle (4) according to the power distribution load coefficient α ₄ from time t5 within the power transmission start period Tb. Are arranged with a time width (= α ₄ · Tb). Note that the time t5 is a time elapsed by a time width (= α ₃ · Tb) from the time t4.

In this modified example, the basic waveform generation circuit 44 has each boundary time t0 (for example, each time t3, t4 shown in FIG. 7) at which the waveform is switched, as shown in the following equation (5) using an arbitrary natural number m. At t5), adjacent waveform values may be set to the same value.
The basic waveform generation circuit 44 may be set so that adjacent waveforms smoothly continue at each boundary time t0 (for example, each time t2,..., T5 shown in FIG. 7).

In the embodiment and the modification described above, each vehicle 11 uses the maximum efficiency frequency ω _k (k = 1,..., N; n is an arbitrary natural number) of the power receiving coil 24 instead of the resonance frequency detector 29. An estimator for estimation may be provided.
The estimator may estimate the maximum efficiency frequency ω _k of the power receiving coil 24 with reference to data stored in advance according to the relative position or distance between each vehicle 11 and the charging station 12, for example. .
In this case, the sweep period Ta having a predetermined period T may be omitted.

In the embodiment and the modification described above, the predetermined period T and the power transmission period Tb may be fixed values, or, for example, according to the moving state of the plurality of vehicles 11 or the power transmission state of the charging station 12. It may be changeable.
For example, the predetermined cycle T and the power transmission period Tb may be changed to a shortening tendency as the moving speed of the plurality of vehicles 11 increases.

  In the above-described embodiment and modification, the non-contact power transmission system 10 is configured to include the predetermined period T by the sweep period Ta and the power transmission period Tb. However, the present invention is not limited to this, for example, when each vehicle 11 is stopped. In this case, only the first predetermined period T may be constituted by the sweep period Ta and the power transmission period Tb, and after this, the sweep period Ta may be omitted.

That is, the predetermined cycle T may be configured by the sweep period Ta and the power transmission period Tb only when any of the plurality of vehicles 11 is in a moving state.
In this case, in the second and subsequent predetermined periods T, the non-contact power transmission system 10 outputs the maximum efficiency frequency ω _k (k = 1,...) Output from the resonance frequency detector 29 in the initial sweep period Ta of the predetermined period T. , N; n is an arbitrary natural number) to calculate the carrier wave fc.

Furthermore, in this case, the non-contact power transmission system 10 has a maximum efficiency frequency ω _k (k = 1) output from the resonance frequency detector 29 in the first predetermined period T of the sweep period Ta in the second and subsequent predetermined periods T. ,..., N; n is an arbitrary natural number) and the required parameter β _k output from the required parameter calculation unit 30 (k = 1,..., N; n is an arbitrary natural number) to calculate the carrier wave fc. Also good.

In the embodiment and the modification described above, the required parameter calculation unit 30 calculates the required parameter β _k (k = 1,..., N; n is an arbitrary natural number), the remaining capacity SOC, the required degree EM, and the burden cost. You may calculate according to only at least any one of CO.

In this case, the required parameter β _k (k = 1,..., N; n is an arbitrary natural number) is a function corresponding to at least one of the remaining capacity SOC, the required degree EM, and the burden cost CO (that is, the function f (SOC), function g (EM), and function h (CO) at least one of them), and the other functions are omitted in the above equation (1).

  In the above-described embodiment and modification, the non-contact power transmission system 10 is configured to include the plurality of vehicles 11 and the charging station 12. However, the present invention is not limited to this. Instead, for example, a plurality of mobile terminals may be provided.

10 Non-contact power transmission system 11 Vehicle (power receiving device)
12 Charging station 21 Battery (electric storage means)
24 Power receiving coil 27 Remaining capacity detector (remaining capacity obtaining means)
28 Input device (acquisition means)
29 Resonant frequency detector (frequency acquisition means)
41 AC power supply (AC power output means)
43 Power distribution load coefficient calculation unit (AC power output means)
44 Basic waveform generation circuit (AC power output means)
45 Amplifier (AC power output means)
46 Power transmission coil

Claims (5)

AC power output means for outputting AC power having a predetermined waveform;
A non-contact power transmission system comprising a power transmission coil for transmitting the AC power output by the AC power output means to a plurality of power receiving coils by a resonance phenomenon,
For the plurality of power receiving coils, comprising a frequency acquisition means for acquiring a maximum efficiency frequency at which the power receiving efficiency of each of the plurality of power receiving coils is maximized,
The AC power output means outputs the AC power obtained by superimposing the waveforms of the maximum efficiency frequencies of the plurality of power receiving coils as the AC power of the predetermined waveform,
The AC power output means sets a peak value of the waveform of the maximum efficiency frequency of each of the plurality of power receiving coils based on a predetermined power distribution load coefficient.
A non-contact power transmission system characterized by that. Power storage means connected to each of the plurality of power receiving coils;
A remaining capacity acquisition means for acquiring the remaining capacity of the power storage means,
The AC power output means sets the peak value of the waveform of the maximum efficiency frequency of each of the plurality of power receiving coils according to the remaining capacity of the power storage means .
The contactless power transmission system according to claim 1. Obtaining means for obtaining at least a request level or a burden cost of a user who uses a power receiving device including each of the plurality of power receiving coils;
The AC power output means sets a peak value of the waveform of the maximum efficiency frequency of each of the plurality of power receiving coils according to at least the required degree or the burden cost .
The non-contact power transmission system according to claim 1 or claim 2, wherein AC power output means for outputting AC power having a predetermined waveform;
A non-contact power transmission system comprising a power transmission coil for transmitting the AC power output by the AC power output means to a plurality of power receiving coils by a resonance phenomenon,
Frequency acquisition means for acquiring a maximum efficiency frequency at which the power receiving efficiency of each of the plurality of power receiving coils is maximum for the plurality of power receiving coils ,
Obtaining means for obtaining at least the degree of demand or burden cost of a user who uses a power receiving device including each of the plurality of power receiving coils;
With
The AC power output means outputs the AC power obtained by arranging the waveforms of the maximum efficiency frequencies of the plurality of power receiving coils in a time division manner as the AC power of the predetermined waveform,
The AC power output means sets a time width in the time division of the waveform of the maximum efficiency frequency of each of the plurality of power receiving coils according to at least the required degree or the burden cost.
A non-contact power transmission system characterized by that. Power storage means connected to each of the plurality of power receiving coils;
A remaining capacity acquisition means for acquiring the remaining capacity of the power storage means,
The AC power output means according to claim, characterized in that the time width at the time division of each of the maximum efficiency frequency of the waveform of the plurality of power receiving coil is set in accordance with the remaining capacity of the storage means 4 The contactless power transmission system described in 1.

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