JP2012029418A - Power transmission system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To safely and efficiently transmit large power without contact.SOLUTION: A power transmission system includes: a transmission antenna 12 to which an AC signal outputted from a signal generation unit is supplied and which generates an electromagnetic field; and a reception antenna 21 generating induction voltage by the electromagnetic field in a position detached from the transmission antenna 12. The system can transmit power without contact. The system also includes a partitioning portion 4 which is arranged between the transmission antenna 12 and the reception antenna 21, can be stretched in accordance with length between the transmission antenna 12 and the reception antenna 21 and separates a space from the transmission antenna 12 to the reception antenna 21 from the other space.

Description

  The present invention relates to a power transmission system that includes a transmission antenna and a reception antenna and transmits power in a contactless manner.

  As this type of power transmission system, a contactless power transmission system (hereinafter also simply referred to as “power transmission system”) disclosed by the applicant in Japanese Patent Application Laid-Open No. 2010-130800 is known. The power transmission system includes a power transmission device having a signal generation unit, a transmission antenna, a first matching unit, and the like, and a power reception device having a reception antenna, a second matching unit, a rectification unit, and the like, and transmits power in a contactless manner. It is configured to be possible. In this power transmission system, the first matching unit of the power transmission device matches the impedance of the signal generation unit side with the impedance of the transmission antenna that changes according to the length (distance) between the power transmission device and shifts to the matching state. And the second matching unit of the power receiving apparatus matches the impedance of the receiving antenna, which changes according to the length between the power receiving device and the impedance on the rectifying unit side (shifts to the matching state). Accordingly, in this power transmission system, the length between the transmission antenna (power transmission device) and the reception antenna (power reception device) that can perform power transmission satisfactorily while minimizing a decrease in power transmission efficiency is minimized. Can be expanded.

JP 2010-130800 A (page 5-9, FIG. 1)

  However, the following problems to be improved exist in the above power transmission system. That is, in this power transmission system, it is possible to increase the length between the transmission antenna and the reception antenna by configuring as described above. There is an increased possibility of “things” in between. In this case, when an object enters between the two antennas, the electromagnetic field is shielded by the object, and there is a risk that the power transmission efficiency may decrease due to this. In addition, when an object enters between both antennas in a state where a strong electromagnetic field is generated to transmit a large amount of power, a property damage accident, fire accident, injury accident, etc. (hereinafter simply referred to as “material damage accident”, etc.) may occur. There is also sex.

  The present invention has been made to solve such a problem, and a main object of the present invention is to provide a power transmission system capable of transmitting a large amount of power safely and efficiently without contact.

  In order to achieve the above object, a power transmission system according to claim 1, wherein a transmission antenna that receives an AC signal output from a signal generation unit to generate an electromagnetic field, and is induced by the electromagnetic field at a position apart from the transmission antenna. A power transmission system that includes a receiving antenna that generates voltage and transmits power in a contactless manner, and is disposed between the transmitting antenna and the receiving antenna and between the transmitting antenna and the receiving antenna. And a partition portion that partitions the space from the transmitting antenna to the receiving antenna with another space.

  According to a second aspect of the present invention, in the power transmission system according to the first aspect, the partition portion is formed of a bellows-like cylinder.

  The power transmission system according to claim 3 is the power transmission system according to claim 1 or 2, wherein the partition portion is formed of a material capable of shielding the electromagnetic field.

  Further, in the power transmission system according to claim 4, in the power transmission system according to any one of claims 1 to 3, the partition section is capable of transmitting the power with a length in a fully extended state. Further, it is defined in advance so as to be equal to or less than the maximum length between the transmitting antenna and the receiving antenna.

  A power transmission system according to a fifth aspect is the power transmission system according to any one of the first to fourth aspects, wherein the power transmission system is disposed between the transmission antenna and the reception antenna and is generated by the transmission antenna. Further, one or a plurality of relay antennas for propagating the electromagnetic field are provided, and the partition unit is configured by connecting a plurality of partition members disposed between the transmission antenna, the relay antenna, and the reception antenna. .

  According to the power transmission system of the first aspect, the power transmission system is disposed between the transmission antenna and the reception antenna, and is configured to be extendable / contractable according to the length between the transmission antenna and the reception antenna. By providing the partition portion that partitions the space leading to the antenna from other spaces, it is possible to reliably prevent an object from entering the space from the transmitting antenna to the receiving antenna. For this reason, according to this power transmission system, it is possible to reliably prevent a reduction in power transmission efficiency due to the entry of an object into the space from the transmission antenna to the reception antenna. Further, according to this power transmission system, it is possible to reliably prevent an object from entering the space from the transmitting antenna to the receiving antenna, and thus it is possible to reliably prevent the occurrence of a property damage accident or the like. Therefore, according to this power transmission system, a large amount of power can be transmitted safely and efficiently without contact.

  According to the power transmission system of claim 2, since the partition portion can be greatly expanded and contracted by configuring the partition portion with the bellows-like cylindrical body, both ends of the partition portion are connected to the transmission antenna and the reception antenna. The length between the transmitting antenna and the receiving antenna can be greatly changed while maintaining the state of being close to each other.

  Further, in the power transmission system according to claim 3, since the partition portion is formed of a material capable of shielding the electromagnetic field, the electromagnetic field in the space outside the partition portion (space other than the space from the transmission antenna to the reception antenna) is increased. The impact can be reduced.

  Further, in the power transmission system according to claim 4, the length of the partition section in the state where the power transmission system is extended to the maximum is specified in advance so as to be equal to or less than the maximum length between the transmitting antenna and the receiving antenna capable of transmitting power. Has been. For this reason, according to this power transmission system, the length between the transmission antenna and the reception antenna can be maintained below the above-mentioned maximum length by bringing both ends of the partition portion close to the transmission antenna and the reception antenna, respectively. Can do. Therefore, according to this power transmission system, even when the user does not know the limit of the length between the two antennas that can perform power transmission, power transmission can be reliably performed.

  Further, according to the power transmission system of claim 5, by including one or more relay antennas disposed between the transmission antenna and the reception antenna and propagating an electromagnetic field generated by the transmission antenna, The length between the transmitting antenna and the receiving antenna that can perform power transmission well can be further expanded. Even when the length between the transmission antenna and the reception antenna is increased by connecting a plurality of partition members arranged between the transmission antenna, the relay antenna, and the reception antenna to configure the partition portion. Large power can be transmitted safely and efficiently without contact.

1 is a configuration diagram showing a configuration of a power transmission system 100. FIG. 1 is a perspective view of a power transmission system 100. FIG. 1 is a side view of a power transmission system 100. FIG. 3 is a circuit diagram of a first matching unit 13 in the power transmission device 2. FIG. 3 is a circuit diagram of a second matching unit 22 in the power receiving device 3. FIG. 5 is a flowchart of power transmission processing 50. 1 is a first explanatory diagram illustrating a method of using a power transmission system 100. FIG. 3 is a second explanatory diagram illustrating a method of using the power transmission system 100. FIG. 4 is a side view of a partition unit 104. FIG. 3 is a perspective view of a partition unit 304. FIG.

  Hereinafter, an embodiment of a power transmission system will be described with reference to the accompanying drawings.

  A power transmission system 100 illustrated in FIG. 1 includes a power transmission device 2, a power reception device 3, and a partition unit 4, and is configured to be able to transmit power from the power transmission device 2 to the power reception device 3 in a contactless manner. In this case, the power transmitted from the power transmission device 2 to the power reception device 3 (received by the power reception device 3) is supplied from the power reception device 3 to the battery 5 and used for charging the battery 5 as an example.

  As illustrated in FIG. 1, the power transmission device 2 includes a signal generation unit 11, a transmission antenna 12, a first matching unit 13, a reflected power measurement unit 14, a first processing unit 15, and a first communication unit 16. Yes. Moreover, in this power transmission apparatus 2, each component which comprises the power transmission apparatus 2 is accommodated in the housing | casing 2a (refer FIG.2, 3).

  The signal generator 11 generates and outputs an AC signal S1. Moreover, the signal generation part 11 is controlled by the 1st process part 15, and is comprised so that the output electric power value of alternating current signal S1 can be changed. Specifically, the signal generator 11 is in any one of a state in which the AC signal S1 is output at a specified power value W1a and a state in which the AC signal S1 is output at a power value W1b that is less than the specified power value W1a. It is possible to operate with. In addition, the signal generator 11 performs first processing using the output power value of the output AC signal S1 (also referred to as “power value W1” when the specified power value W1a and the power value W1b are not particularly distinguished) as output power information. A function of outputting to the unit 15 is provided. The transmission antenna 12 is formed in a coil shape (a helical spring shape or a planar coil shape) as an example, and receives an AC signal S1 output from the signal generator 11 to generate an electromagnetic field. The transmission antenna 12 constitutes a pair of resonators (a pair of self-resonant coils) together with a reception antenna 21 of the power receiving device 3 described later, and resonates in an electromagnetic field.

  The first matching unit 13 is disposed between the signal generator 11 and the transmission antenna 12 (specifically, interposed in a transmission path connecting the signal generator 11 and the transmission antenna 12). The impedance on the signal generating unit 11 side is matched with the impedance (input impedance) of the transmitting antenna 12 that changes according to the length between the receiving antenna 21 and the signal generating unit 11 and the transmitting antenna 12 are shifted to a matching state. ). In this example, as an example, as shown in FIG. 4, the first matching unit 13 includes a variable capacitor 13 a connected in parallel to the transmission antenna 12 and a series (specifically, And a variable capacitor 13b connected in series to a parallel circuit including the transmission antenna 12 and the variable capacitor 13a. Further, the first matching unit 13 is configured such that the electrostatic capacitances of the variable capacitors 13a and 13b are controlled independently and independently by the control signal S2 output from the first processing unit 15, thereby transmitting antenna 12 (in detail, It is possible to match the input impedance of the transmission antenna 12 viewed from the signal generation unit 11 side and the signal generation unit 11 (specifically, the output impedance of the signal generation unit 11 viewed from the transmission antenna 12 side).

  The reflected power measurement unit 14 is disposed between the signal generation unit 11 and the first matching unit 13 (specifically, the reflection power measurement unit 14 is interposed in a transmission path that connects the signal generation unit 11 and the first matching unit 13). The power value (reflected wave power value) W2 of the AC signal S1 that is reflected by the transmission antenna 12 out of the AC signal S1 output from the signal generation unit 11 to the transmission antenna 12 and returns to the signal generation unit 11 side. Measured and output to the first processing unit 15 as reflected power information.

  As an example, the first processing unit 15 includes a CPU and an internal memory (both not shown), and controls the signal generating unit 11 and controls the first matching unit 13 to control the signal generating unit 11 (specifically). Specifically, control processing for shifting between the reflected power measurement unit 14 and the signal generation unit 11) and the transmission antenna 12 to the above matching state, parameter information of the first matching unit 13 in this matching state (in this example, each Information related to the capacitance values of the variable capacitors 13a and 13b) Transmission processing for transmitting D1 to the power receiving device 3 via the first communication unit 16, and power values described later measured by the power measuring unit 24 of the power receiving device 3 A reception process for receiving W3 via the first communication unit 16 is executed. The 1st communication part 16 is comprised by the radio | wireless transmitter / receiver as an example, and is comprised so that communication with the 2nd communication part 26 mentioned later of the power receiving apparatus 3 is possible. Further, the first communication unit 16 has a function of detecting the reception intensity D2 for the radio signal of the power receiving device 3 and outputting the reception intensity information to the first processing unit as reception intensity information.

  The power receiving device 3 includes a receiving antenna 21, a second matching unit 22, a rectifying unit 23, a power measuring unit 24, a second processing unit 25, and a second communication unit 26. The receiving antenna 21 is formed in the same coil shape as the transmitting antenna 12 as an example, and has the same (or almost the same) inductance as the transmitting antenna 12. The reception antenna 21 is electromagnetically coupled to the transmission antenna 12 of the power transmission device 2 (that is, due to an electromagnetic field generated by the transmission antenna 12), and generates an induced voltage V1 between both ends thereof.

  The second matching unit 22 is disposed between the receiving antenna 21 and the rectifying unit 23 (specifically, interposed in a transmission path connecting the receiving antenna 21 and the rectifying unit 23), and is a transmitting antenna. The impedance (output impedance) of the receiving antenna 21 that changes according to the length between the rectifying unit 12 and the impedance on the rectifying unit 23 side is matched (the receiving antenna 21 and the rectifying unit 23 are shifted to a matching state). In this example, as an example, as shown in FIG. 5, the second matching unit 22 includes a variable capacitor 22 a connected in parallel to the reception antenna 21 and a series connection to the reception antenna 21 (that is, the reception antenna 21. And a variable capacitor 22b connected in series to a parallel circuit composed of the variable capacitor 22a, and is configured in the same circuit as the first matching unit 13. In addition, the second matching unit 22 is configured such that the electrostatic capacitances of the variable capacitors 22a and 22b are separately and independently controlled by the control signal S3 output from the second processing unit 25, whereby the receiving antenna 21 (in detail, The output impedance of the receiving antenna 21 viewed from the rectifying unit 23 side and the rectifying unit 23 (specifically, the input impedance of the rectifying unit 23 viewed from the receiving antenna 21 side) can be matched.

  The rectifying unit 23 inputs the induced voltage V1 generated in the receiving antenna 21 via the second matching unit 22, and generates a voltage (DC voltage in this example) Vo to be supplied to the battery 5 based on the induced voltage V1. To do. Specifically, the rectifying unit 23 includes a rectifying circuit and a smoothing circuit, rectifies and smoothes the induced voltage (AC voltage) V1 output from the second matching unit 22, and generates the voltage Vo. The voltage Vo thus output is output to the battery 5. In this example, as an example, each component in the power receiving device 3 operates by being supplied with this voltage Vo from the rectifying unit 23. Note that a battery (not shown) that charges the voltage Vo supplied from the rectifier 23 may be provided, and each component in the power receiving device 3 may be operated by the voltage of the battery. Moreover, it can replace with the rectifier 23 and can comprise a voltage generation part with a DC-DC converter, an AC-DC converter, or an AC-AC converter, for example.

  The power measuring unit 24 is interposed in a transmission path that connects the rectifying unit 23 and the battery 5, measures the power value W <b> 3 of the voltage Vo supplied from the power receiving device 3 to the battery 5, and supplies power information W <b> 3 as supply power information. 2 is output to the processing unit 25. The second processing unit 25 is configured to include a CPU and an internal memory (both not shown) as an example, and receives the parameter information D1 from the power transmission device 2, and the second matching based on the parameter information D1. The control unit 22 to control the receiving antenna 21 and the battery 5 (specifically, the rectifying unit 23 and the battery 5) to shift to the matching state, and the power value W3 measured by the power measuring unit 24 is 2 A transmission process for transmitting to the power transmission device 2 via the communication unit 26 is executed. The 2nd communication part 26 is comprised by the radio | wireless transmitter / receiver as an example, and is comprised so that communication with the 1st communication part 16 of the power transmission apparatus 2 is possible. Further, the second communication unit 26 periodically outputs a radio signal so that the power transmission device 2 detects the presence of the power reception device 3.

  In the power receiving device 3, each component constituting the power receiving device 3 is accommodated in a housing 3a (see FIGS. 2 and 3) such as a cart used in a golf course, for example. The housing 3a is provided with wheels 3b used when the power receiving device 3 is moved. In this example, a battery 5 as a supply target for supplying power transmitted by the power transmission system 100 is fixed to the housing 3a.

  As shown in FIGS. 1, 7, and 8, the partition unit 4 is disposed between the transmission antenna 12 of the power transmission device 2 and the reception antenna 21 of the power reception device 3 when the power transmission system 100 is used (at the time of operation). Then, the space F from the transmitting antenna 12 to the receiving antenna 21 (the columnar space F connecting the transmitting antenna 12 and the receiving antenna 21 (see FIGS. 7 and 8)) is replaced with another space (a space outside the partition unit 4). And partition. Moreover, the partition part 4 is comprised with the bellows-shaped cylinder formed of the sheet | seat 31 which has a softness | flexibility, as shown in FIG. In this case, on the front surface (or back surface) of the sheet body 31, as shown in the figure, a mesh body (mesh) 32 formed of a non-conductive magnetic material (for example, ferrite) is disposed. Yes. For this reason, the partition part 4 can shield an electromagnetic field, and functions as a shield (cover) that regulates leakage of the electromagnetic field generated by the transmission antenna 12 to the outside of the space F.

  Further, the base end portion 4 a of the partition portion 4 is fixed to the housing 2 a so that the opening on the base end portion 4 a side faces the transmission antenna 12. In addition, a fixing member 4 c that engages with a fixing member 3 c provided in the housing 3 a of the power receiving device 3 is provided at the distal end portion 4 b of the partition portion 4. Moreover, the partition part 4 can be expanded and contracted and bent by being configured in a bellows shape as described above. For this reason, as shown in FIGS. 7 and 8, the partition unit 4 places the power reception device 3 with respect to the power transmission device 2 in a state where the reception antenna 21 of the power reception device 3 and the distal end portion 4 b of the partition unit 4 face each other. When they are brought into contact with or separated from each other, they expand and contract according to the length between the transmission antenna 12 of the power transmission device 2 and the reception antenna 21 of the power reception device 3. In addition, the partition unit 4 has a length in a state where the partition unit 4 is extended to the maximum (for example, the state shown in FIG. 8), which is equal to or less than the maximum length between the transmission antenna 12 and the reception antenna 21 that can perform power transmission satisfactorily. It is stipulated that

  Next, as an example of a method of using the power transmission system 100, the power receiving device 3 connected to the battery 5 is moved to the vicinity of the power transmitting device 2 together with the battery 5 in a state where the power transmitting device 2 is previously disposed at a predetermined position. The method of charging the battery 5 will be described, and the operation of the power transmission system 100 at that time will also be described.

  Prior to the start of charging (power transmission), the power receiving device 3 is aligned (moved). Specifically, as shown in FIG. 3, the power receiving device 3 is moved in the direction of approaching the power transmitting device 2 (in the direction of the arrow shown in FIG. 3) so that the receiving antenna 21 and the partition unit 4 of the power receiving device 3 The housing 3a of the power receiving device 3 and the tip portion 4b of the partition portion 4 are brought into contact with each other so that the opening portion of the tip portion 4b faces the opening portion. Next, as shown in FIG. 7, the fixing member 3c disposed on the housing 3a and the fixing member 4c disposed on the distal end portion 4b are engaged with each other so that the distal end portion 4b is attached to the housing 3a. After fixing, the power receiving device 3 is further brought closer to the power transmitting device 2 side. At this time, the partition unit 4 contracts as the power receiving device 3 approaches the power transmitting device 2. Thereby, the positioning of the power receiving device 3 is completed in a state where the partition portion 4 is disposed between the transmitting antenna 12 of the power transmitting device 2 and the receiving antenna 21 of the power receiving device 3.

  In this power transmission system 100, since the partition part 4 is formed in a bellows shape, the partition part 4 can be greatly expanded and contracted. For this reason, the length between the transmitting antenna 12 and the receiving antenna 21 is relatively maintained while maintaining the proximal end portion 4a and the distal end portion 4b of the partition portion 4 close to the transmitting antenna 12 and the receiving antenna 21, respectively. It can be freely changed. Further, in this power transmission system 100, the length of the partition unit 4 in the maximum extended state (see FIG. 8) is the maximum between the transmission antenna 12 and the reception antenna 21 that can perform power transmission satisfactorily. It is specified to be less than the length. For this reason, as long as the base end part 4a and the front-end | tip part 4b of the partition part 4 are each contacting the power transmission apparatus 2 and the power receiving apparatus 3, the length between the transmission antenna 12 and the receiving antenna 21 is below the said maximum length. Maintained. Moreover, in this power transmission system 100, since the partition part 4 is formed so that an electromagnetic field can be shielded, the influence of the electromagnetic field in the space outside the partition part 4 can be reduced.

  Subsequently, the power transmission system 100 is operated. The power transmission system 100 repeatedly executes the power transmission process 50 shown in FIG. 6 in the operating state. In the power transmission process 50, the first processing unit 15 of the power transmission apparatus 2 first executes a process of detecting the power reception apparatus 3 (step 51). Specifically, in the power transmission device 2, the first communication unit 16 repeatedly detects and outputs the reception intensity D <b> 2 by the radio signal output from the second communication unit 26 of the power reception device 3. For this reason, in this process, the first processing unit 15 detects the presence of the power receiving device 3 by determining whether or not the reception intensity D2 has reached a predetermined reference intensity.

  When the presence of the power receiving device 3 is detected in the above processing (that is, when the reception strength D2 reaches the reference strength), the first processing unit 15 starts power transmission with small power (step 52). Specifically, the 1st process part 15 performs control with respect to the signal generation part 11, and outputs alternating current signal S1 by the electric power value W1b. As a result, the AC signal S1 output from the signal generation unit 11 is supplied to the transmission antenna 12 via the reflected power measurement unit 14 and the first matching unit 13, and transmission with low power is started. The reflected power measuring unit 14 measures and outputs the reflected wave power value W2.

  On the other hand, in the power receiving device 3, an induced voltage V <b> 1 is generated in the receiving antenna 21 that is electromagnetically coupled to the transmitting antenna 12, and the rectifying unit 23 rectifies the induced voltage V <b> 1 output via the second matching unit 22 to generate a voltage. Generate Vo. As a result, supply of the voltage Vo to the battery 5 is started, and the power measurement unit 24, the second processing unit 25, and the second communication unit 26 in the power receiving device 3 receive the supply of the voltage Vo and start operation. . Specifically, the power measuring unit 24 starts measuring the power value W3 for the voltage Vo supplied from the rectifying unit 23 to the battery 5 and outputting it to the second processing unit 25. In addition, the second communication unit 26 starts communication with the first communication unit 16 of the power transmission device 2.

  Next, the first processing unit 15 acquires the reflected wave power value W2 output from the reflected power measuring unit 14 (step 53), and whether or not the reflected wave power value W2 is equal to or less than a predetermined threshold value. Is discriminated (step 54). As a result of this comparison, when the reflected wave power value W2 is not less than or equal to the threshold value, the first processing unit 15 executes matching processing (step 55). Simultaneously with the matching process in the power transmission device 2 by the first processing unit 15, the second processing unit 25 also executes the matching process in the power receiving device 3.

  Specifically, in this matching process, in the power transmission device 2, the first processing unit 15 outputs the control signal S2 to the first matching unit 13 so that the reflected wave power value W2 decreases. A process of changing the capacitances of the variable capacitors 13a and 13b of the matching unit 13 is executed. Subsequently, the first processing unit 15 performs a transmission process of transmitting the parameter information D1 (capacitances of the variable capacitors 13a and 13b) to the power receiving device 3 via the first communication unit 16. On the other hand, in the power receiving device 3, the second communication unit 26 receives the parameter information D <b> 1 and outputs it to the second processing unit 25. Further, the second processing unit 25 calculates the capacitances of the corresponding variable capacitors 22a and 22b in the second matching unit 22 based on the capacitances of the variable capacitors 13a and 13b indicated by the parameter information D1. Execute the process to be controlled. In this example, as an example, the second processing unit 25 matches the capacitance of the variable capacitor 22a with the capacitance of the variable capacitor 13a, and changes the capacitance of the variable capacitor 22b to the capacitance of the variable capacitor 13b. The capacitances of the variable capacitors 22a and 22b are controlled so as to match.

  The first processing unit 15 repeatedly executes the above steps 53, 54, and 55 until the reflected wave power value W2 is equal to or lower than the threshold value. In the power receiving device 3, each time the second processing unit 25 acquires new parameter information D <b> 1 from the power transmitting device 2, the electrostatic capacity of the variable capacitors 22 a and 22 b is repeatedly controlled as described above.

  As a result, in step 54, when the reflected wave power value W2 is equal to or lower than the threshold value, the first processing unit 15 has completed matching between the transmission antenna 12 and the reflected power measuring unit 14 by the first matching unit 13. And transmission / reception power measurement processing is executed (step 56). In this case, when the matching between the transmission antenna 12 and the reflected power measurement unit 14 by the first matching unit 13 is completed, the reception antenna 21 is configured the same as the transmission antenna 12, and the second matching unit 22 is the first matching unit. Since the variable capacitors 22a and 22b of the second matching unit 22 are controlled to have the same capacitance as the corresponding variable capacitors 13a and 13b of the first matching unit 13, the power receiving device 3, the matching between the receiving antenna 21 and the rectifying unit 23 is completed. In this example, as an example, when the reflected wave power value W2 is equal to or lower than the threshold value, the first processing unit 15 completes the matching between the transmission antenna 12 and the signal generation unit 11 by the first matching unit 13. Although the configuration for determining that it has been performed is employed to shorten the transition time to the matching state, when the reflected wave power value W2 is minimized, the first processing unit 15 performs transmission by the first matching unit 13. A configuration for determining that the matching between the antenna 12 and the signal generation unit 11 is completed may be employed.

  In the power transmission / reception power measurement processing, the first processing unit 15 first acquires the power value W1b of the AC signal S1 from the signal generation unit 11 and stores it in the internal memory. Next, the first processing unit 15 causes the second processing unit 25 of the power receiving device 3 to transmit the power value W <b> 3 measured by the power measuring unit 24 via the second communication unit 26. Subsequently, the first processing unit 15 acquires the power value W3 via the first communication unit 16 and stores it in the internal memory. Thereby, the power transmission / reception power measurement process is completed. Note that the second processing unit 25 of the power receiving device 3 may adopt a configuration in which the acquisition of the power value W3 from the power measurement unit 24 and the transmission of the power value W3 from the second communication unit 26 are repeatedly executed. . In this configuration, the first processing unit 15 only needs to receive the power value W3 transmitted from the power receiving device 3 via the first communication unit 16, so the first processing unit 15 receives the second processing unit 25 from the first processing unit 15. Thus, the process of transmitting the power value W3 is not necessary.

  Next, the first processing unit 15 calculates the transmission efficiency A (= W3 / W1b) based on the power values W1b and W3 stored in the internal memory, and is it equal to or greater than a predetermined value? It is determined whether or not (step 57). As a result of the determination, when the transmission efficiency A is less than the predetermined value, the first processing unit 15 determines that the electromagnetic coupling state between the transmission antenna 12 and the reception antenna 21 is not suitable for power transmission. Then, the control for the signal generator 11 is executed to stop the output of the AC signal S1 at the power value W1b (step 58), and the power transmission process is terminated. This avoids inefficient power transmission.

  On the other hand, when it is determined that the transmission efficiency A is equal to or greater than the predetermined value, the first processing unit 15 determines that the electromagnetic coupling state between the transmission antenna 12 and the reception antenna 21 is in a state suitable for power transmission. Electric power transmission is started (step 59). As a result, power transmission with high power is started in a state where efficient power transmission is possible. Specifically, the 1st process part 15 performs control with respect to the signal generation part 11, and outputs alternating current signal S1 by the prescription | regulation electric power value W1a. As a result, prescribed power is supplied from the power transmitting device 2 to the power receiving device 3, and the battery 5 connected to the power receiving device 3 is charged with the voltage Vo.

  In this power transmission system 100, since the partition 4 is disposed between the transmission antenna 12 of the power transmission device 2 and the reception antenna 21 of the power reception device 3, the space F extending from the transmission antenna 12 to the reception antenna 21 The entry of objects is reliably prevented. For this reason, in this power transmission system 100, a reduction in power transmission efficiency due to the entry of objects into the space F is prevented. In addition, since the entry of objects into the space F is reliably regulated, it is possible to reliably prevent the occurrence of property damage accidents and the like.

  Subsequently, the first processing unit 15 determines whether or not a predetermined stop condition is satisfied during execution of power transmission with the large power (step 60), and determines that the stop condition is satisfied. When it does, control with respect to the signal generation part 11 is performed, and the output of AC signal S1 is stopped (step 61). Thereby, the power transmission process in the power transmission system 100 is completed. In this case, examples of the stop condition include an input of a forced stop signal for power transmission processing to the first processing unit 15 and an input of a signal indicating that the charging of the battery 5 has been completed.

  As described above, according to the power transmission system 100, the transmission antenna is disposed between the transmission antenna 12 and the reception antenna 21, and is configured to be expandable / contractable according to the length between the antennas 12 and 21. By providing the partition part 4 that partitions the space F extending from the antenna to the receiving antenna from other spaces, entry of objects into the space F can be reliably prevented. For this reason, according to this electric power transmission system 100, the fall of the electric power transmission efficiency by the approach of the thing to the space F can be prevented reliably. Further, according to the power transmission system 100, it is possible to reliably prevent an object from entering the space F, and thus it is possible to reliably prevent the occurrence of a property damage accident or the like. Therefore, according to the power transmission system 100, a large amount of power can be transmitted safely and efficiently without contact.

  Moreover, according to this power transmission system 100, since the partition part 4 was comprised by the bellows-shaped cylinder, the partition part 4 can be expanded / contracted largely, Therefore The base end part 4a and the front-end | tip part 4b of the partition part 4 The length between the transmission antenna 12 and the reception antenna 21 can be greatly changed while maintaining the state in which the antenna is close to the transmission antenna 12 and the reception antenna 21, respectively.

  Further, according to the power transmission system 100, the partition part 4 is formed of a material capable of shielding the electromagnetic field, thereby reducing the influence of the electromagnetic field in the space outside the partition part 4 (external space other than the space F). be able to.

  Further, in the power transmission system 100, the length of the partition unit 4 in a state where the power transmission system 100 is extended to the maximum is defined to be equal to or less than the maximum length between the transmission antenna 12 and the reception antenna 21 capable of transmitting power. ing. Therefore, according to the power transmission system 100, the power transmission device 2 and the power reception device 3 are arranged so that the proximal end portion 4a and the distal end portion 4b of the partition portion 4 are close to the transmission antenna 12 and the reception antenna 21, respectively. The length between the transmission antenna 12 and the reception antenna 21 can be maintained below the maximum length. Therefore, according to the power transmission system 100, even when the user does not know the limit of the length between the two antennas that can perform power transmission, the power transmission can be reliably performed.

  The configuration of the power transmission system is not limited to the configuration described above, and can be changed as appropriate. For example, the power transmission system 200 shown in FIG. 9 can be employed. As shown in the figure, the power transmission system 200 includes one or a plurality (1 in this example) disposed between the transmission antenna 12 of the power transmission device 2 and the second matching unit 22 of the power reception device 3. The relay antenna 61 is provided. The relay antenna 61 is formed in the same coil shape as the transmission antenna 12 and the reception antenna 21, has the same (or almost the same) inductance as the transmission antenna 12 and the reception antenna 21, and is generated by the transmission antenna 12. It has a function to propagate (relay) the electromagnetic field. The power transmission system 200 includes a partition unit 104 in place of the partition unit 4 described above. As shown in the figure, the partition unit 104 connects a plurality of (two in this example) bellows-shaped and cylindrical partition members 141 disposed between the transmission antenna 12, the relay antenna 61, and the reception antenna 21. Configured. In addition, the same code | symbol is attached | subjected about the same component as the above-mentioned electric power transmission system 100, and the overlapping description is abbreviate | omitted.

  The power transmission system 200 includes one or more relay antennas 61 disposed between the transmission antenna 12 and the reception antenna 21 to propagate (relay) an electromagnetic field generated by the transmission antenna 12. Thus, the length between the transmitting antenna 12 and the receiving antenna 21 that can perform power transmission satisfactorily can be further expanded. In addition, since the partition unit 104 is configured by including a plurality of partition members 141 disposed between the transmission antenna 12, the relay antenna 61, and the reception antenna 21, the length between the transmission antenna 12 and the reception antenna 21. Even when the power spreads, large power can be transmitted safely and efficiently without contact.

  Moreover, it can replace with the partition part 4 and the structure provided with the partition part 304 shown in FIG. For example, the partition 304 is formed of a cylindrical body 341 made of a foamed resin (porous resin) that can be expanded and contracted and bent, and a non-conductive magnetic body (for example, ferrite). And a net-like body (mesh) 342 disposed on the outer peripheral surface (or inner peripheral surface) of the body 341. Even in the configuration including the partition unit 304, the same effect as that of the power transmission system 100 including the partition unit 4 described above can be realized.

  Moreover, although the partition part 4 formed so that the electromagnetic field can be shielded by using the sheet body 31 provided with the mesh body 32 formed of a magnetic material has been described as an example, it has a function of shielding the electromagnetic field. Instead, it is also possible to employ a partition section whose main function is to restrict the entry of objects into the space F. In addition, the example in which the power transmitted by the power transmission system 100 is supplied to the battery 5 (the battery 5 is charged with the transmitted power) has been described above. It is not limited to 5, and various electronic devices and electrical devices are included. In addition, the configuration in which the first communication units 16 and 26 communicate with each other wirelessly has been described as an example, but a non-contact communication method (communication method using light or the like) other than wireless may be employed.

2 Power transmission device 3 Power reception device 4, 104, 304 Partition unit 11 Signal generation unit 12 Transmission antenna 21 Reception antenna 31 Sheet body 32, 342 Net body 61 Relay antenna 100, 200 Power transmission system 141 Partition member 341 Tube S1 AC signal V1 Induced voltage

Claims (5)

A transmission antenna that receives an AC signal output from a signal generator to generate an electromagnetic field, and a reception antenna that generates an induced voltage by the electromagnetic field at a position apart from the transmission antenna, and transmits power in a contactless manner A power transmission system
The space between the transmitting antenna and the receiving antenna and configured to be expandable / contractable according to the length between the transmitting antenna and the receiving antenna so that the space from the transmitting antenna to the receiving antenna is different. A power transmission system including a partition section that partitions the space.   The power transmission system according to claim 1, wherein the partition portion is configured by a bellows-like cylinder.   The power transmission system according to claim 1, wherein the partition portion is formed of a material capable of shielding the electromagnetic field.   The partition section is defined in advance so that a length in a state where the partition section is extended to a maximum is equal to or less than a maximum length between the transmission antenna and the reception antenna capable of transmitting the power. 4. The power transmission system according to any one of 3. One or more relay antennas disposed between the transmitting antenna and the receiving antenna to propagate the electromagnetic field generated by the transmitting antenna;
The power transmission system according to any one of claims 1 to 4, wherein the partition unit is configured by connecting a plurality of partition members disposed between the transmission antenna, the relay antenna, and the reception antenna.

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