JP6305439B2 - Resonant power transmission device - Google Patents

Description

  The present invention relates to a resonant power transmission apparatus that performs power transmission at a high frequency.

  FIG. 13 shows a resonant power transmission device according to the prior art. This resonance type power transmission apparatus is configured by connecting a resonance type transmission antenna 102 including an inductor L11 to the output of the class E type power supply circuit 101 (see, for example, Non-Patent Document 1).

2013 IEICE General Conference BCS-1-16

WO2013 / 046536

However, in the prior art, it is not possible to maintain a resonance condition that follows the impedance fluctuation on the receiving side. Therefore, when the distance between the resonant transmission antenna 102 and the resonant reception antenna fluctuates, there is a problem in that power transmission efficiency decreases. Further, when the distance between the resonant transmission antenna 102 and the resonant reception antenna varies, or when the load impedance on the reception side varies, the class E power supply circuit 101 falls out of the resonance operation condition, and the power conversion efficiency decreases. was there.
In order to solve the above problem, an automatic matching circuit is required between the class E power supply circuit 101 and the resonant transmission antenna 102. However, in that case, there is a problem that the apparatus cannot be reduced in size and weight. In addition, since the number of parts increases, there is a problem that the cost cannot be reduced. There is a problem that the power conversion efficiency of the entire apparatus is reduced by the automatic matching circuit.

  On the other hand, in order to eliminate the need for the automatic matching circuit, a device for injecting a correction current having a phase difference with respect to a drive voltage into a transmission antenna in a power transmission system using a class D power supply circuit is known (for example, Patent Document 1). By injecting this correction current, automatic tuning can be performed so as to realize the resonance state without adjusting the resonance frequency of the transmitting antenna. However, the class D power supply circuit is intended for power transmission in the kHz band, and has a problem that it cannot be applied to the MHz band.

  The present invention has been made to solve the above-described problems, and can automatically match the output impedance of the resonant transmission antenna and the input impedance of the resonant reception antenna, and can achieve a high frequency of 2 MHz or higher. It is an object of the present invention to provide a resonance type power transmission device that can perform power transmission.

The resonant power transmission device according to the present invention includes two systems of power elements that perform switching operation at a high frequency of 2 MHz or more, two systems of resonant circuit elements that resonantly switch the switching operation of the corresponding power elements, and each power element. A high-frequency pulsed voltage signal of 2 MHz or higher is sent to the high-frequency pulse drive circuit for driving each power element and the phase difference between the two voltage signals is fixed and sent to the high-frequency pulse drive circuit. A phase difference generation circuit that drives a drive circuit, and a resonance type transmission antenna that generates transmission power by inputting two types of power obtained by a switching operation by a power element and performing a resonance operation, and a resonance type transmission antenna The resonance condition setting circuit for setting the resonance condition and 2 obtained by the switching operation by the power element A impedance matching circuit to match the resonance condition between the integration of the power and the resonant transmitting antennas, resonant transmitting antennas, and the middle-point to the common potential, consists of one coil to enter the power of two systems Is.

The resonant power transmission device according to the present invention includes two power elements that perform switching operation at a high frequency of 2 MHz or higher, two resonant circuit elements that perform resonant switching of the switching operation of the corresponding power element, A high-frequency pulsed voltage signal of 2 MHz or higher is sent to the power element, and the high-frequency pulse drive circuit that drives each power element and the phase difference between the two voltage signals are fixed and sent to the high-frequency pulse drive circuit. A phase difference generation circuit for driving a high-frequency pulse drive circuit, a transformer for synthesizing two powers obtained by switching operation by a power element into one power, and one power synthesized by the transformer are input. A resonant transmission antenna that generates transmission power by performing a resonance operation, and a resonance condition of the resonant transmission antenna Comprising a resonant condition setting circuit for setting, and an impedance matching circuit to match the resonance condition between the two systems of power and transformer obtained by the switching operation of the power element, the transformer, and the intermediate point to a common potential, It has a primary coil for inputting two systems of power .

  According to the present invention, since it is configured as described above, the output impedance of the resonant transmission antenna and the input impedance of the resonant reception antenna can be automatically matched, and power transmission is performed at a high frequency of 2 MHz or higher. be able to.

It is a figure which shows the structure of the resonance type power transmission system provided with the resonance type power transmission device which concerns on Embodiment 1 of this invention. It is a figure which shows the structure of the resonance type | mold transmission antenna in Embodiment 1 of this invention. It is a figure which shows the circuit structure of the resonance type power transmission apparatus which concerns on Embodiment 1 of this invention. It is a figure which shows operation | movement of the resonance type electric power transmission apparatus which concerns on Embodiment 1 of this invention, (a) It is a figure which shows the waveform of 2 outputs from an E class type power supply circuit, (b) The waveform of received electric power FIG. It is a figure explaining the principle of operation of the resonance type electric power transmission apparatus concerning Embodiment 1 of this invention. It is a figure which shows another circuit structure of the resonance type power transmission apparatus which concerns on Embodiment 1 of this invention. It is a figure which shows the circuit structure of the resonance type power transmission apparatus which concerns on Embodiment 2 of this invention. It is a figure which shows the circuit structure of the resonance type power transmission apparatus which concerns on Embodiment 3 of this invention. It is a figure which shows operation | movement of the resonance type electric power transmission apparatus which concerns on Embodiment 3 of this invention, (a) It is a figure which shows the waveform of 2 outputs from a class E type power supply circuit, (b) The waveform of received electric power FIG. It is a figure which shows the structure of the variable type inductor in Embodiment 3 of this invention. It is a figure which shows another structure of the variable type inductor in Embodiment 3 of this invention. It is a figure which shows another structure of the variable type inductor in Embodiment 3 of this invention. It is a circuit diagram which shows the structure of the conventional resonance type power transmission apparatus.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
Embodiment 1 FIG.
FIG. 1 is a diagram showing a configuration of a resonant power transmission system including a resonant power transmission device 1 according to Embodiment 1 of the present invention.
As shown in FIG. 1, the resonance type power transmission system includes a class E type power supply circuit (resonance type power supply circuit) 2, a resonance type transmission antenna 3, a resonance type reception antenna 4, and a reception circuit 5. Note that the class E power supply circuit 2 and the resonant transmission antenna 3 constitute a resonant power transmission apparatus 1.

  The class E power supply circuit 2 is disposed in front of the resonant transmission antenna 3 and controls the supply of power to the resonant transmission antenna 3. The class E type power supply circuit 2 is an inverter power supply circuit that inputs two types of alternating current (V1, V2) with a phase difference fixedly controlled by inputting direct current or alternating current. In FIG. 1, a class E power supply circuit is shown as the resonant power supply circuit. However, the present invention is not limited to this, and any resonant power supply circuit that can operate at a frequency in the MHz band may be used.

The resonant transmitting antenna 3 is a resonant power transmitting antenna that transmits power from the class E power supply circuit 2 to the resonant receiving antenna 4 (not limited to non-contact). The resonant transmission antenna 3 receives two systems of alternating current (V1, V2) output from the class E power supply circuit 2 and generates a transmission power by performing a resonance operation to the resonant reception antenna 4. Power transmission is implemented.
As shown in FIG. 2A, the resonant transmission antenna 3 may be configured by arranging two coils 31 and 32 (arbitrary shapes such as a helical shape and a spiral shape) side by side in series. 2 (b), one coil 32 may be fitted inside the other coil 31. 1 and 2 show a case where the resonant transmission antenna 3 is configured by using two separated coils 31 and 32, but the present invention is not limited to this. For example, as shown in FIG. The resonant transmission antenna 3 may be configured by using a single coil and arranging a common RTN terminal from an intermediate point of the coil.

The resonant receiving antenna 4 is a resonant power receiving antenna that receives power from the resonant transmitting antenna 3 (not limited to non-contact). The electric power received by the resonance type receiving antenna 4 is supplied to a load device or the like (not shown) via the receiving circuit 5.
The resonance type receiving antenna 4 may be constituted by one coil (arbitrary shape such as a helical shape or a spiral shape), or may be constituted by two coils by separately providing a feeding coil. The resonant frequency of the resonant receiving antenna 4 is set to the same frequency as that of the resonant transmitting antenna 3.

The receiving circuit 5 is arranged between the resonant receiving antenna 4 and the load device, and rectifies the power (AC output) received by the resonant receiving antenna 4. The receiving circuit 5 is an AC input-DC output type power supply circuit.
Note that the transmission method of the resonant power transmission system in the case of wireless power transmission is not particularly limited, and any of a magnetic field resonance method, an electric field resonance method, and an electromagnetic induction method may be used.

Next, a specific circuit configuration example of the class E power supply circuit 2 shown in FIG. 1 will be described with reference to FIG.
As shown in FIG. 3, the class E type power supply circuit 2 includes power elements Q1, Q21, resonance circuit elements (capacitors C1, C21, inductors L2, L22 and capacitors C2, C22), inductors L1, L21, and a high-frequency pulse drive circuit. 21, a phase difference generation circuit 22, an impedance matching circuit (capacitors C 3 and C 23), and a resonance condition setting circuit (capacitors C 5 and C 25). Note that the capacitors C5 and C25 may be included in the class E power supply circuit 2 shown in FIG. 1 or may be provided outside.

  The power elements Q1 and Q21 are switching elements that perform a switching operation at a high frequency of 2 MHz or more in order to convert the input DC voltage Vin into AC. The power elements Q1 and Q21 are not limited to field effect transistors (FETs) for RF (Radio Frequency), and elements such as Si-MOSFETs, SiC-MOSFETs, and GaN-FETs can be used. It is.

  The resonant circuit elements (capacitors C1 and C21, inductors L2 and L22, and capacitors C2 and C22) are elements for resonantly switching the switching operations of the corresponding power elements Q1 and Q21. As the capacitors C1, C2, C21, and C22, ceramic capacitors, film capacitors, and the like can be used. Further, as the inductors L2 and L22, an air core coil, a magnetic inductor, or the like can be used.

  The inductors L1 and L21 function to temporarily hold the energy of the input DC voltage Vin for each switching operation of the corresponding power elements Q1 and Q21. As the inductors L1 and L21, magnetic inductors can be used.

  The high-frequency pulse drive circuit 21 is a circuit that drives the power elements Q1 and Q21 by sending a high-frequency pulsed voltage signal of 2 MHz or higher to the G terminal of the power element Q1 and the G terminal of the power element Q21. The high-frequency pulse drive circuit 21 is a circuit configured so that a high-speed ON / OFF output can be performed by using an FET element or the like as a totem pole circuit configuration.

  The phase difference generating circuit 22 is a circuit for driving the high-frequency pulse drive circuit 21 by sending two high-frequency pulsed voltage signals of 2 MHz or higher such as a logic signal to the high-frequency pulse drive circuit 21. At that time, the timing of driving the power elements Q1 and Q21 is controlled by arbitrarily fixing the phase difference between the two voltage signals. In addition to the above, the phase difference generation circuit 22 includes a frequency setting oscillator, a flip-flop, an inverter, and the like.

  The impedance matching circuit (capacitors C3 and C23) is an impedance matching between the output of the class E power supply circuit 2 (two powers obtained by the switching operation by the power elements Q1 and Q21) and the resonant transmission antenna 3 ( Resonance balance balance). As the capacitors C3 and C23, ceramic capacitors, film capacitors, and the like can be used.

  The resonance condition setting circuit (capacitors C5 and C25) is for setting the resonance condition of the resonant transmission antenna 3. As the capacitors C5 and C25, a ceramic capacitor, a film capacitor, or the like can be used.

Next, the operation of the resonant power transmission system configured as described above will be described. Hereinafter, the operation of the circuit constituted by the upper power element Q1 in FIG. 3 will be described. Further, it is assumed that the DC voltage Vin is input to the class E power supply circuit 2.
First, a DC voltage Vin of a primary power supply (not shown) is input to the class E power supply circuit 2, converted into a high frequency alternating current in the MHz band, and output to the resonant transmission antenna 3 in two systems. In a specific operation of the class E power supply circuit 2, first, the input DC voltage Vin is applied to the D terminal of the power element Q1 through the inductor L1. The power element Q1 converts the voltage into a positive AC voltage by an ON / OFF switching operation. During this conversion operation, the inductor L1 temporarily holds energy to assist in converting power from direct current to alternating current.

  Here, the switching operation of the power element Q1 is a resonant circuit element including the capacitor C1, the inductor L2, and the capacitor C2 so that ZVS (zero voltage switching) is established so that the switching loss due to the product of the Ids current and the Vds voltage is minimized. The resonance switching condition is set at. By this resonance switching operation, an AC voltage with the RTN potential as an axis is output as the output voltage Vout.

  The power element Q1 is driven by inputting a pulsed voltage signal output from the high-frequency pulse drive circuit 21 that receives an arbitrary pulsed voltage signal from the phase difference generation circuit 22 to the G terminal of the power element Q1. Is going. At this time, the drive frequency of the power element Q1 becomes the operating frequency of the resonant power transmission device 1 and is determined by the setting of the oscillator circuit inside the phase difference generation circuit 22.

  On the other hand, the operation of the circuit composed of the lower power element Q21 in FIG. 3 is the same as described above. The drive timing of the power elements Q1 and Q21 is controlled by the phase difference generation circuit 22. Then, by arbitrarily fixing the phase difference between the outputs V1 and V2 of the class E type power supply circuit 2 (for example, 90 degrees), as shown in FIG. 4, the resonance type reception for receiving the transmission power from the resonance type transmission antenna 3 Matching is automatically achieved with respect to impedance fluctuation accompanying the change in the position of the antenna 4. For example, when the position of the resonant receiving antenna 4 changes with respect to the resonant transmitting antenna 3, an automatic matching operation is performed so that the phase difference between the voltage and current in the resonant receiving antenna 4 becomes small. As a result, the effective power that can be extracted from the resonant receiving antenna 4 can be increased.

Here, the operation principle of the present invention will be described with reference to FIG. FIG. 5 represents the outputs I1 and I2 and the received inputs Vin and Iin of FIG. 4 in vector.
In FIG. 5, the outputs I1 and I2 have a phase difference with respect to the reception input Vin. On the other hand, the phase difference between the output I1 and the output I2 is 90 degrees. Since the combined current of these outputs I1 and I2 becomes the reception input Iin, it is possible to automatically match the phase of the reception input Iin with the phase of the reception input Vin.

The resonant transmission antenna 3 performs a resonance operation by the two systems of high-frequency alternating current, and transmits power to the resonant reception antenna 4. Thereafter, the resonant receiving antenna 4 performs a resonant operation in the same manner as the resonant transmitting antenna 3 by power transmission from the resonant transmitting antenna 3. The resonant receiving antenna 4 outputs high-frequency alternating current to the receiving circuit 5. Thereafter, the receiving circuit 5 rectifies the high-frequency alternating current and outputs a direct current.
Further, even when the position of the resonant receiving antenna 4 changes with respect to the resonant transmitting antenna 3, automatic matching is performed so that the phase difference between the voltage and current in the resonant receiving antenna 4 becomes small. As a result, the effective power that can be extracted from the resonant receiving antenna 4 can be increased.

As described above, according to the first embodiment, the resonant power supply circuit is configured to have a two-output configuration, each output is connected to the resonant transmission antenna 3, and the phase difference between the two outputs is arbitrarily fixed. As a result, the output impedance of the resonant transmission antenna 3 and the input impedance of the resonant reception antenna 4 can be automatically matched, and power can be transmitted at a high frequency of 2 MHz or higher.
As a result, even if the distance between the resonant transmission antenna 3 and the resonant reception antenna 4 varies, high power transmission efficiency can be maintained. Further, even if the distance between the resonant transmission antenna 3 and the resonant reception antenna 4 fluctuates or the load impedance on the receiving side fluctuates, the E-class power supply circuit 2 does not deviate from the resonance operating condition. Power conversion efficiency can be maintained. Further, since the automatic matching circuit between the class E type power supply circuit 2 and the resonant transmission antenna 3 which has been conventionally required is not required, the apparatus can be reduced in size and weight. Further, since the number of parts can be reduced compared to the conventional configuration, the cost can be reduced. In addition, the efficiency of power conversion efficiency can be increased.

In the above description, the circuit configuration as shown in FIG. 3 is shown as a configuration example of the resonant power transmission device 1. However, the present invention is not limited to this. For example, a circuit configuration as shown in FIG.
In the configuration shown in FIG. 6, inductors L3 and L23 and capacitors C4 and C24 are elements that form an impedance matching circuit together with the capacitors C3 and C23. As the capacitors C4 and C24, a ceramic capacitor, a film capacitor, or the like can be used. Further, as the inductors L3 and L23, an air core coil, a magnetic inductor, or the like can be used. These additional elements can make the impedance matching range wider.

Embodiment 2. FIG.
In the second embodiment, the resonance type transmission antenna 3 is constituted by one antenna. FIG. 7 is a circuit diagram showing a configuration example of the resonant power transmission apparatus 1 according to the second embodiment of the present invention. A resonance type power transmission device 1 according to the second embodiment shown in FIG. 7 adds a transformer T1 to the resonance type power transmission device 1 according to the second embodiment shown in FIG. 3, and a resonance condition setting circuit (capacitors C5, C25). ) And the resonant transmission antenna 3 is composed of one antenna. Other configurations are the same, and only different parts will be described.

  The transformer T1 synthesizes two systems of power obtained by the switching operation by the power element into one system of power. That is, the transformer T1 has a voltage amplitude generated in the secondary coil N3 by arbitrarily fixing the phase difference between the voltage applied to the primary coil N1 and the voltage applied to the primary coil N2 by the phase difference generation circuit 22. To control. The transformer T1 is composed of a transformer using a magnetic material such as a ferrite core.

The resonant transmission antenna 3 receives one system of power generated by the transformer T1 and generated in the secondary coil N3, and generates transmission power by performing a resonance operation.
The impedance matching circuit (capacitors C3 and C23) performs impedance matching (balance matching of resonance conditions) between the two systems of power obtained by the switching operation by the power elements Q1 and Q21 and the transformer T1.

  In FIG. 7, two elements of capacitors C5 and C25 are used as the resonance condition setting circuit. However, the resonance condition setting circuit may be composed of only one element. In this case, an element having a value that is a series combined impedance of the capacitors C5 and C25 is used.

  As described above, according to the second embodiment, the transformer T1 is used to synthesize the two systems of power into the power of the first system, etc. In addition to the effects of the first embodiment, the second embodiment The number of turns of the resonant transmission antenna 3 can be halved for one configuration.

  It is noted that inductors L3 and L23 and capacitors C4 and C24 may be added to the configuration shown in FIG. Thereby, the impedance matching range can be made wider.

Embodiment 3 FIG.
In the third embodiment, an example in which amplitude difference control is performed in addition to the phase difference setting of two outputs of the resonance type power supply circuit will be described. FIG. 8 is a circuit diagram showing a configuration example of the resonant power transmission apparatus 1 according to the third embodiment of the present invention. Resonant type power transmission device 1 according to Embodiment 3 shown in FIG. 8 uses variable inductors as inductors L2 and L22 constituting the resonant circuit element of resonant type power transmission device 1 according to Embodiment 2 shown in FIG. It has been changed. Other configurations are the same, and only different parts will be described.

  The inductors L2 and L22 are variable inductors having variable inductance values. By variably controlling the inductance value of the inductor L2 or the inductor L22, the amplitude difference between the outputs V1 and V2 of the class E type power supply circuit 2 is controlled. Then, as shown in FIG. 9, by controlling the amplitude difference in addition to the phase difference setting of the outputs V1 and V2, the distortion and phase of the voltage waveform of the transmission power output from the resonant transmission antenna 3 are controlled. Thus, automatic impedance matching with the resonant receiving antenna 4 can be performed.

Next, a configuration example of the variable inductors L2 and L22 will be described with reference to FIGS.
FIG. 10 shows variable inductors L2 and L22 of a type in which a motor control circuit 233 is used as an electronic component and the magnetic path length of the coil 232 is automatically changed by the motor control circuit 233. In this configuration, the variable control circuit 231 drives the motor control circuit 233 to physically vary the magnetic path length of the coil 232, thereby varying the inductance value. In FIGS. 10A and 10B, the number of turns of the coil 232 is the same.

  FIG. 11 shows variable inductors L2 and L22 of a type in which an FET 234 is used as an electronic component and the number of turns of the coil 232 is automatically adjusted by the FET 234. In this configuration, the FET 234 is connected to each winding point of the coil 232, and the variable control circuit 231 is used to switch each FET 234 on / off, or by switching pulse width modulation (PWM) or the like. By making it variable, the inductance value is made variable. The FET 234 is an element such as a Si-MOSFET, SiC-MOSFET, GaN-FET, or RF FET, or an element in which these elements are connected in series to form an OFF type body diode.

  FIG. 12 shows variable inductors L2 and L22 of a type in which an FET 234 is used as an electronic component and the parallel connection of the coil 232 is automatically changed by the FET 234. In this configuration, the FET 234 is connected to each coil 232 connected in parallel, the FET 234 is switched ON / OFF by the variable control circuit 231, or the pulse width modulation (PWM) is switched to connect the coils 232 in parallel. By making it variable, the inductance value is made variable. The FET 234 is an element such as a Si-MOSFET, SiC-MOSFET, GaN-FET, or RF FET, or an element in which these elements are connected in series to form an OFF type body diode.

FIG. 8 shows a case where both the inductors L2 and L22 are variable inductors. However, the present invention is not limited to this, and only one of the inductors L2 and L22 may be a variable inductor. In this case, however, the operating range of automatic impedance matching with the resonant receiving antenna 4 is narrowed.
Further, inductors L3 and L23 and capacitors C4 and C24 may be added to the configuration shown in FIG. Thereby, the impedance matching range can be made wider.

  Further, within the scope of the present invention, the invention of the present application can be freely combined with each embodiment, modified with any component in each embodiment, or omitted with any component in each embodiment. .

  The resonant power transmission device according to the present invention can automatically match the output impedance of the resonant transmitting antenna and the input impedance of the resonant receiving antenna, and can transmit power at a high frequency of 2 MHz or higher. It is suitable for use in a resonant power transmission device that performs power transmission at a high frequency.

  DESCRIPTION OF SYMBOLS 1 Resonance type power transmission device, 2 Class E type power supply circuit (resonance type power supply circuit), 3 Resonance type transmission antenna, 4 Resonance type reception antenna, 5 Reception circuit, 31, 32 Coil, 21 High frequency pulse drive circuit, 22 Phase difference Generation circuit, 231 variable control circuit, 232 coil, 233 motor control circuit, 234 FET.

Claims (12)

Two power elements that perform switching operation at a high frequency of 2 MHz or higher;
Two systems of resonant circuit elements for resonant switching of the switching operation of the corresponding power element;
A high-frequency pulse drive circuit that sends a high-frequency pulsed voltage signal of 2 MHz or more to each of the power elements to drive the power elements;
A phase difference generating circuit that fixes a phase difference between the two voltage signals and sends the high-frequency pulse drive circuit to the high-frequency pulse drive circuit;
A resonant transmission antenna that inputs transmission power obtained by switching operation by the power element and generates transmission power by performing resonance operation;
A resonance condition setting circuit for setting a resonance condition of the resonant transmission antenna;
An impedance matching circuit for matching resonance conditions between the two types of power obtained by the switching operation by the power element and the resonant transmission antenna;
The resonant transmitting antennas, and the middle-point to the common potential, resonant power transmission apparatus characterized by comprising a single coil for inputting power of the two systems. Two power elements that perform switching operation at a high frequency of 2 MHz or higher;
Two systems of resonant circuit elements for resonant switching of the switching operation of the corresponding power element;
A high-frequency pulse drive circuit that sends a high-frequency pulsed voltage signal of 2 MHz or more to each of the power elements to drive the power elements;
A phase difference generating circuit that fixes a phase difference between the two voltage signals and sends the high-frequency pulse drive circuit to the high-frequency pulse drive circuit;
A transformer that combines two powers obtained by the switching operation by the power element into one power;
A resonant transmission antenna that inputs a single power synthesized by the transformer and generates a transmission power by performing a resonance operation;
A resonance condition setting circuit for setting a resonance condition of the resonant transmission antenna;
An impedance matching circuit that adjusts resonance conditions between the power of the two systems obtained by the switching operation by the power element and the transformer;
The transformer includes a primary side coil that inputs the power of the two systems with a common point at an intermediate point. The resonant power transmission device according to claim 1, wherein the resonant circuit element includes a variable inductor that varies an inductance value. The resonant power transmission device according to claim 2, wherein the resonant circuit element includes a variable inductor having a variable inductance value. The resonant power transmission apparatus according to claim 1, wherein the power element is a field effect transistor other than a field effect transistor for RF. The resonant power transmission apparatus according to claim 2, wherein the power element is a field effect transistor other than a field effect transistor for RF. The resonant power transmission apparatus according to claim 1, wherein the resonant transmission antenna performs power transmission by magnetic field resonance. The resonant power transmission apparatus according to claim 2, wherein the resonant transmission antenna performs power transmission by magnetic field resonance. The resonant power transmission apparatus according to claim 1, wherein the resonant transmission antenna performs power transmission by electric field resonance. The resonant power transmission apparatus according to claim 2, wherein the resonant transmission antenna performs power transmission by electric field resonance. The resonant power transmission apparatus according to claim 1, wherein the resonant transmission antenna performs power transmission by electromagnetic induction. The resonant power transmission device according to claim 2, wherein the resonant transmission antenna performs power transmission by electromagnetic induction.

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