JP6252638B2 - Power transmission device and power receiving device - Google Patents

Description

  The present invention relates to a power transmission device and a power receiving device.

  Conventionally, in so-called wireless power transmission or wireless power supply (WPS) in which power is transmitted wirelessly, power (energy) can be transmitted and received without using a cable between two spatially separated points. Do. There are two types of wireless power transmission: a method using electromagnetic induction and a method using radio waves. In addition, a method using magnetic field resonance (also referred to as magnetic field resonance, magnetic resonance, or magnetic field resonance mode) has been proposed (see, for example, Patent Document 1).

  In addition, for example, a charging system that charges a plurality of sensing devices simultaneously and equally is disclosed. According to this charging system, a plurality of sensing devices that receive electromagnetic waves and charge electric power obtained from the energy of the electromagnetic waves, a casing unit that stores liquid in the recesses, and a radio wave radiation unit that radiates electromagnetic waves in the recesses And a stirring unit that stirs the liquid contained in the recess in the recess. Each sensing device is mixed in the liquid accommodated in the recess and moves in the recess according to the stirring of the stirring unit, and charges the electric power obtained by receiving the electromagnetic wave radiated from the radio wave radiating unit (for example, , See Patent Document 2).

  In addition, a transmitter for a search system is disclosed in which a charging circuit that receives radio waves and charges a battery is provided to obtain power that can be transmitted far and can withstand long-term use. According to this transmitter for search systems, an antenna that receives electromagnetic waves, a charging circuit that charges the storage battery with the electric energy of the received electromagnetic waves, a receiver that receives a call signal, a transmitter driven by the storage battery, And a storage device. The storage device stores owner identification information for identifying the owner of the device. In addition, the receiver receives a call signal including the owner identification information, activates the transmitter when the storage battery is charged, and transmits the signal including the owner identification information stored in the storage device to the transmitter. (For example, refer to Patent Document 3).

International Publication No. WO98 / 34319 JP 2009-253997 A JP 2005-229150 A

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a non-contact power transmission device, a power reception device, and a power transmission device that simultaneously charge power reception devices having different charging powers. .

A power transmission device according to an embodiment of the present invention includes a primary coil disposed in a power transmission device and connected to an AC power source, and a primary resonance coil that receives power from the primary coil by electromagnetic induction. a power transmission section that have a, is disposed on the power receiving side device, and the secondary side resonance coil for receiving the power from the power transmission unit by magnetic resonance occurring between the primary side resonance coil of the power transmitting unit, the 2 A power receiving unit having a secondary coil that receives power from the secondary resonance coil by electromagnetic induction, a bridge circuit having a switch element connected to the secondary resonance coil, and a power receiving device including the power receiving unit and identification information for identifying a charging information generation unit for generating a charging information including the information indicating the charging power of the device, when a plurality of the device from the power transmitting apparatus is receiving, the charge power of the own device Max If not, by varying the duty ratio or the phase of the pulse voltage for driving the switching elements of the bridge circuit based on variable information for changing the resonance frequency or the Q value of the resonance circuit included in the power receiving unit of the own device the resonant frequencies or Q value of the resonance circuit of the power receiving unit, and a variable to possible frequency or Q value supplying charging power to the charging electric power corresponding to the devices other than the largest device from transmitted power of the power transmission device, the self When the charging power of the device is the maximum, the resonance frequency or Q value of the resonance circuit of the power reception unit is fixed by fixing the duty ratio or phase of the pulse voltage that drives the switch element of the bridge circuit And a control unit.

  A contactless power transmission device, a power reception device, and a power transmission device that charge power reception devices with different charging powers simultaneously can be provided.

It is a figure which shows the magnetic field resonance type electric power transmission method. It is a figure which shows the outline | summary of a magnetic field resonance type electric power transmission system. 3 is a diagram illustrating an example of a configuration of a control unit of the power transmission system according to Embodiment 1. FIG. 3 is a diagram illustrating a circuit configuration of a bridge type balanced circuit 160. FIG. 3 is a diagram illustrating waveforms of control signals SW1 to SW4 that drive a bridge-type balanced circuit 160 according to Embodiment 1. FIG. 3 is a diagram illustrating waveforms of control signals SW1 to SW4 that drive a bridge-type balanced circuit 160 according to Embodiment 1. FIG. 3 is a diagram illustrating waveforms of control signals SW1 to SW4 that drive a bridge-type balanced circuit 160 according to Embodiment 1. FIG. It is a figure which shows the state of the electric current and phase in resonance frequency control. It is a figure which shows the state of the electric current and phase in resonance frequency control. It is a figure which shows the state of an electric current and a phase when a bimodal characteristic appears. It is a figure which shows the state of the electric current and phase in resonance frequency control when a bimodal characteristic appears. It is a figure which shows the example of the change of the transmission power at the time of performing the resonant frequency control corresponding to a bimodal characteristic. It is a figure which shows the frequency dependence of an electric power transmission system. It is a figure explaining the method of sweeping the resonant frequency of a coil. It is a figure which shows the example of the structure which switches resonance frequency control and bimodal resonance control. It is a flowchart which shows the rough process sequence of resonance frequency control. It is a flowchart which shows the rough process sequence of resonance frequency control. It is a figure which shows one Example of the system which has an apparatus provided with the non-contact type power transmission apparatus and power receiving apparatus of a strong coupling system. It is a figure which shows one Example of the hardware of a power transmission apparatus. It is a figure which shows one Example of the hardware of an apparatus provided with a power receiving apparatus. 3 is a diagram illustrating a circuit configuration of a power reception unit 35. FIG. It is a figure which shows the waveform of control signal SW1-SW4 which drives the bridge type | mold balance circuit 160 of Embodiment 2. FIG. It is a figure which shows the waveform of control signal SW1-SW4 which drives the bridge type | mold balance circuit 160 of Embodiment 2. FIG. It is a figure which shows the waveform of control signal SW1-SW4 which drives the bridge type | mold balance circuit 160 of Embodiment 2. FIG. It is a flowchart which shows one Example of operation | movement of a power transmission apparatus. It is a figure which shows one Example of the data structure of charge information, power receiving information, and efficiency information. It is a figure which shows one Example of the data structure of combination information. It is a figure which shows one Example of the equivalent circuit of the non-contact-type charging system of magnetic field resonance and electric field resonance. It is a figure which shows one Example of the equivalent circuit of the non-contact-type charging system of magnetic field resonance. It is a figure which shows an example of a simulation result. It is a figure which shows an example of the relationship between a power transmission frequency and the Q value of a power receiving part. It is a flowchart which shows one Example of operation | movement of an apparatus. It is a figure which shows one Example of the data structure of Q value variable information. It is a figure which shows one Example of the system which has the power transmission apparatus of Embodiment 2, and a power receiving apparatus. FIG. 10 is a diagram illustrating an example of a system including a power transmission device and a power reception device according to a third embodiment. It is a flowchart which shows one Example of operation | movement of the main apparatus. It is a flowchart which shows one Example of operation | movement of the main apparatus. It is a flowchart which shows one Example of operation | movement of apparatuses other than a main body. FIG. 10 is a flowchart illustrating an example of operation of the power transmission device according to the third embodiment. FIG. 10 is a diagram illustrating an example of a system including a power transmission device, a power reception device, and an external device according to a fourth embodiment. It is a flowchart which shows one Example of operation | movement of an external device. It is a flowchart which shows one Example of operation | movement of an external device. FIG. 20 is a flowchart showing an example of operation of the device in the fourth embodiment. FIG. 10 is a flowchart illustrating an example of operation of the power transmission device according to the fourth embodiment. It is a figure which shows the positional relationship of a power transmission resonance coil and a power reception resonance coil. It is a figure which shows the positional relationship of a power transmission resonance coil and a power reception resonance coil. FIG. 10 is a diagram illustrating an example of a control unit that is a subject of the fifth embodiment. It is a figure which shows one Example of the data structure of state-efficiency information. FIG. 22 is a diagram illustrating an example of a data structure of combination information according to the fifth embodiment. FIG. 10 is a flowchart showing an example of the operation of a control unit as a main body of the fifth embodiment.

  Hereinafter, embodiments of the present invention to which a power receiving device, a power receiving device, and a power transmitting device for charging a power receiving device with different charging power at the same time are applied will be described.

<Embodiment 1>
The first embodiment is intended to be able to adjust the resonance frequency of a coil at high speed and accurately in real time in a magnetic field resonance type power transmission system.

  A magnetic resonance power transmission system to which the present invention is applied will be described.

  The method using magnetic field resonance (magnetic field resonance type) can transmit higher power than the method using radio waves, and the transmission distance can be longer than that of electromagnetic induction method. There is an advantage that can be reduced.

  In the method using magnetic field resonance, energy transmission can be performed with high efficiency by setting the resonance frequencies of the power transmission coil and the power reception coil to the same value and performing power transmission at frequencies in the vicinity thereof. It becomes possible.

  In order to increase the efficiency of power transmission in a magnetic field resonance type power transmission system, there is one in which a higher frequency than the frequency of the oscillation signal on the primary coil side is used as the resonance frequency on the secondary coil side (Patent Document 1). According to this, the capacitance can be reduced and the coupling coefficient between the primary coil and the secondary coil can be increased apparently.

  By increasing the degree of coupling between the coils, the efficiency of power transmission can be increased to some extent.

  In order to increase the efficiency of power transmission, it is conceivable to make the resonance peak of each coil as sharp as possible. For this purpose, for example, the Q value of each coil may be designed to be high.

  However, when the Q value is increased, the sensitivity to the deviation of the resonance frequency of both coils is increased, that is, the influence on the reduction of the power transmission efficiency due to the deviation of the resonance frequency of both coils is increased. There is a problem of end.

  For example, the resonance frequency of the coil changes due to changes in environmental factors such as temperature, changes in inductance and capacitance due to the approach of a conductor such as a person or metal, or a magnetic body. There is also a shift in the resonance frequency due to variations in manufacturing.

  Therefore, in the magnetic field resonance type power transmission system having a high Q value, a mechanism for adjusting the resonance frequency of the coil in response to an environmental change or the like is required in order to take advantage of the maximum merit.

  In order to adjust the resonance frequency of the coil to the target frequency, it is necessary to adjust L (inductance) of the coil or C (capacitance) of the capacitor.

  In the power transmission system (power transmission device) 1 of the first embodiment described below, L or C of the coil (resonance circuit) is based on the phase difference Δφ between the voltage of the AC power supply (drive voltage) and the current flowing through the coil. Real-time resonance frequency control is performed.

  In addition, when the coupling between the power transmission coil and the power reception coil is increased and a bimodal characteristic (split) appears, a peak (split peak) appears at the frequency of the AC power supply in order to suppress a decrease in power transmission efficiency. As described above, the resonance frequency of the power transmission coil or the power reception coil is shifted. In order to distinguish the resonance frequency control in this case from the resonance frequency control in the case where the bimodal characteristic does not appear, it may be referred to as “bimodal resonance control”.

  Further, the resonance frequency control in the case of not including “bimodal resonance control” may be described as “normal resonance frequency control”. When simply “resonance frequency control” is described, “bimodal resonance control” is included in principle.

  1 and 2, the power transmission system 100 includes a power transmission system coil SC, a power reception system coil JC, an AC power supply 11, a power transmission side control unit 14, a device 21 serving as a load, and a power reception side control unit 24.

In FIG. 2, the power transmission coil SC includes a power supply coil 12 and a power transmission resonance coil 13. The power supply coil 12 is formed by winding a metal wire such as a copper wire or an aluminum wire a plurality of times around a circumference, and an AC voltage (high-frequency voltage) from the AC power source 11 is applied to both ends thereof.

  The power transmission resonance coil 13 includes a coil 131 in which a metal wire such as a copper wire or an aluminum wire is wound circumferentially, and a capacitor 132 connected to both ends of the coil 131, thereby forming a resonance circuit. The resonance frequency f0 is expressed by the following equation (1).

なお、Ｌはコイル１３１のインダクタンス、Ｃはコンデンサ１３２の静電容量である。

Note that L is the inductance of the coil 131, and C is the capacitance of the capacitor 132.

  The coil 131 of the power transmission resonance coil 13 is, for example, a one-turn coil. Although various types of capacitors are used as the capacitor 132, those having as little loss as possible and having a sufficient breakdown voltage are preferable. In the first embodiment, a variable capacitor is used as the capacitor 132 in order to vary the resonance frequency. As the variable capacitor, for example, a variable capacitance device manufactured using MEMS technology is used. A variable capacitance device (varactor) using a semiconductor may be used.

  The power supply coil 12 and the power transmission resonance coil 13 are arranged so as to be electromagnetically closely coupled to each other. For example, they are arranged on the same plane and concentrically. That is, for example, the power supply coil 12 is arranged in a state of being fitted on the inner peripheral side of the power transmission resonance coil 13. Or you may arrange | position with an appropriate distance on the same axis | shaft.

  In this state, when an AC voltage is supplied from the AC power supply 11 to the power supply coil 12, a resonance current flows through the power transmission resonance coil 13 by electromagnetic induction caused by an alternating magnetic field generated in the power supply coil 12. That is, electric power is supplied from the power supply coil 12 to the power transmission resonance coil 13 by electromagnetic induction.

  The power receiving system coil JC includes a power receiving resonance coil 22 and a power extraction coil 23. The power receiving resonance coil 22 includes a coil 221 around which a metal wire such as a copper wire or an aluminum wire is wound, and a capacitor 222 connected to both ends of the coil 221. The resonance frequency f0 of the power receiving resonance coil 22 is expressed by the above equation (1) based on the inductance of the coil 221 and the capacitance of the capacitor 222.

  The coil 221 of the power receiving resonance coil 22 is, for example, a one-turn coil. As the capacitor 222, various types of capacitors are used as described above. In the first embodiment, a variable capacitor is used as the capacitor 222 in order to vary the resonance frequency. As the variable capacitor, for example, a variable capacitance device manufactured using MEMS technology is used. A variable capacitance device (varactor) using a semiconductor may be used.

  The power extraction coil 23 is formed by winding a metal wire such as a copper wire or an aluminum wire a plurality of times in a circumferential shape, and a device 21 as a load is connected to both ends thereof.

  The power receiving resonance coil 22 and the power extraction coil 23 are disposed so as to be electromagnetically closely coupled to each other. For example, they are arranged on the same plane and concentrically. That is, for example, the power extraction coil 23 is disposed in the inner peripheral side of the power reception resonance coil 22. Or you may arrange | position with an appropriate distance on the same axis | shaft.

  In this state, when a resonance current flows through the power receiving resonance coil 22, a current flows through the power extraction coil 23 by electromagnetic induction caused by the alternating magnetic field generated thereby. That is, electric power is transmitted from the power receiving resonance coil 22 to the power extraction coil 23 by electromagnetic induction.

  Since the power transmission coil SC and the power reception coil JC transmit power wirelessly by magnetic field resonance, are the coil surfaces parallel to each other and the coil axes coincide with each other as shown in FIG. Alternatively, they are arranged within an appropriate distance from each other so as not to deviate so much. For example, when the diameters of the power transmission resonance coil 13 and the power reception resonance coil 22 are about 100 mm, they are arranged within a distance range of about several hundred mm.

  In the power transmission system 100 shown in FIG. 2, the direction along the coil axis KS is the main radiation direction of the magnetic field KK, and the direction from the power transmission system coil SC toward the power reception system coil JC is the power transmission direction SH.

  Here, when the resonance frequency fs of the power transmission resonance coil 13 and the resonance frequency fj of the power reception resonance coil 22 both coincide with the frequency fd of the AC power supply 11, the maximum power is transmitted. However, if the resonance frequencies fs and fj are deviated from each other or they are deviated from the frequency fd of the AC power supply 11, the transmitted power is lowered and the efficiency is lowered.

  That is, in FIG. 13, the horizontal axis represents the frequency fd [MHz] of the AC power supply 11, and the vertical axis represents the magnitude of transmitted power [dB]. A curve CV1 indicates a case where the resonance frequency fs of the power transmission resonance coil 13 and the resonance frequency fj of the power reception resonance coil 22 match. In this case, according to FIG. 13, the resonance frequencies fs and fj are 13.56 MHz.

  Curves CV2 and CV3 indicate cases where the resonance frequency fj of the power reception resonance coil 22 is higher by 5% and 10% than the resonance frequency fs of the power transmission resonance coil 13, respectively.

  In FIG. 13, when the frequency fd of the AC power supply 11 is 13.56 MHz, the highest power is transmitted in the curve CV1, but sequentially decreases in the curves CV2 and CV3. Further, when the frequency fd of the AC power supply 11 is shifted from 13.56 MHz, the power transmitted in any of the curves CV1 to CV3 is reduced except when it is slightly shifted upward.

  Therefore, it is necessary to make the resonance frequencies fs and fj of the power transmission resonance coil 13 and the power reception resonance coil 22 coincide with the frequency fd of the AC power supply 11 as much as possible.

  In FIG. 14, the horizontal axis represents the frequency [MHz], and the vertical axis represents the magnitude of the current [dB] flowing through the coil. A curve CV4 shows a case where the resonance frequency of the coil matches the frequency fd of the AC power supply 11. In this case, according to FIG. 14, the resonance frequency is 10 MHz.

  Curves CV5 and CV6 indicate the case where the resonance frequency of the coil is higher or lower than the frequency fd of the AC power supply 11.

In FIG. 14, the maximum current flows in the curve CV4, but the current decreases in both the curves CV5 and CV6. In addition, when the Q value of the coil is high, the influence on the decrease of the current or the transmission power due to the deviation of the resonance frequency is large.

  Therefore, in the power transmission system 100 according to the first embodiment, the phase φvs of the AC power supply 11 and the phases φis and φij of the current flowing through the power transmission resonance coil 13 and the power reception resonance coil 22 are transmitted by the power transmission side control unit 14 and the power reception side control unit 24. Is used to control the resonance frequency.

  Here, the power transmission side control unit 14 detects the phase φvs of the voltage Vs supplied to the power transmission system coil SC and the phase φis of the current Is flowing through the power transmission system coil SC, and the phase difference Δφs is a predetermined target value φms. Thus, the resonance frequency fs of the power transmission coil SC is varied. Data representing the target value φms is stored in an internal memory of the control unit 152 described later.

  That is, the power transmission side control unit 14 includes a current detection sensor SE1, phase detection units 141 and 142, and a phase transmission unit 145.

  The current detection sensor SE <b> 1 detects the current Is flowing through the power transmission resonance coil 13. As the current detection sensor SE1, a Hall element, a magnetoresistive element, a detection coil, or the like can be used. The current detection sensor SE1 outputs a voltage signal corresponding to the waveform of the current Is, for example.

  The phase detector 141 detects the phase φvs of the voltage Vs supplied to the power supply coil 12. For example, the phase detection unit 141 outputs a voltage signal corresponding to the waveform of the voltage Vs. In this case, the voltage Vs may be output as it is, or may be divided and output by an appropriate resistor. Therefore, the phase detection unit 141 can be configured by a simple electric wire or by one or a plurality of resistors.

  The phase detector 142 detects the phase φis of the current Is flowing through the power transmission resonance coil 13 based on the output from the current detection sensor SE1. For example, the phase detection unit 142 outputs a voltage signal corresponding to the waveform of the current Is. In this case, the phase detection unit 142 may output the output of the current detection sensor SE1 as it is. Therefore, the current detection sensor SE1 can also serve as the phase detection unit 142.

  The phase transmission unit 145 transmits information about the phase φvs of the voltage Vs supplied to the power supply coil 12 to the power receiving side control unit 24, for example, wirelessly. For example, the phase transmission unit 145 transmits a voltage signal corresponding to the waveform of the voltage Vs as an analog signal or a digital signal. In that case, in order to improve the S / N ratio, a voltage signal corresponding to the waveform of the voltage Vs may be multiplied by an integral multiple and transmitted.

  The power receiving side control unit 24 detects the phase φvs of the voltage VS supplied to the power transmission coil SC and the phase φij of the current IJ flowing through the power receiving coil JC so that the phase difference Δφj becomes a predetermined target value φmj. In addition, the resonance frequency fj of the power receiving coil JC is varied.

  That is, the power receiving side control unit 24 includes a current detection sensor SE2, a phase reception unit 241, and a phase detection unit 242.

  The current detection sensor SE2 detects a current Ij flowing through the power receiving resonance coil 22. As the current detection sensor SE2, a Hall element, a magnetoresistive element, a detection coil, or the like can be used. The current detection sensor SE2 outputs a voltage signal corresponding to the waveform of the current Ij, for example.

  The phase receiver 241 receives information about the phase φvs transmitted from the phase transmitter 145 and outputs the information. When the voltage signal is multiplied by the phase transmission unit 145, the phase reception unit 241 performs frequency division to restore the original. For example, the phase receiving unit 241 outputs a voltage signal corresponding to the voltage Vs.

  The phase detector 242 detects the phase φij of the current Ij flowing through the power receiving resonance coil 22 based on the output from the current detection sensor SE2. For example, the phase detection unit 242 outputs a voltage signal corresponding to the waveform of the current Ij. In this case, the phase detection unit 242 may output the output of the current detection sensor SE2 as it is. Therefore, the current detection sensor SE2 can also serve as the phase detection unit 242.

  This will be described in more detail with reference to FIG. In FIG. 3, elements having the same functions as those shown in FIG. 2 may be denoted by the same reference numerals and description thereof may be omitted or simplified.

In FIG. 3, a power transmission system (power transmission device) 1 </ b> B includes a power transmission device 3 and a power reception device 4.

  The power transmission device 3 includes an AC power supply 11, a power supply coil 12 including a power supply coil 12 and a power transmission resonance coil 13, a resonance frequency control unit CTs, and the like.

  The power receiving device 4 includes a power receiving system coil JC including a power receiving resonance coil 22 and a power extraction coil 23, a resonance frequency control unit CTj, and the like.

  The resonance frequency control unit CTs on the power transmission side includes a phase comparison unit 151, a control unit 152, and a bridge type balanced circuit 160. The phase comparison unit 151 is an example of a phase detection unit or a second phase detection unit. The control unit 152 is an example of a resonance frequency control unit or a second resonance frequency control unit. The bridge type balanced circuit 160 is an example of a bridge circuit or a second bridge circuit.

  The phase comparison unit 151 compares the phase φis of the current Is detected by the current detection sensor SE1 with the phase φvs of the voltage Vs of the AC power supply 11, and outputs a phase difference Δφs that is the difference between them.

  Control unit 152 sets and stores target value φms of phase difference Δφs. Therefore, control unit 152 is provided with an internal memory for storing target value φms. As the target value φms, as described later, for example, “−π” or “a value obtained by adding an appropriate correction value a to −π” or the like is set.

  The target value φms may be set by selecting from one or a plurality of data stored in advance, or may be performed by a command from a CPU or a keyboard.

  Based on the phase difference Δφs output from the phase comparator 151 and the gate signal Gate input from the bridge-type balanced circuit 160, the control unit 152 causes the bridge-type balanced circuit 160 to set the phase difference to the target value φms. A drive signal for driving the included four switch elements SW1 to SW4 is generated and output. The target value φms is set so that the sign is opposite to the target phase difference Δφs. Therefore, when the absolute values of the phase difference Δφs and the target value φms coincide with each other, the phase difference Δφs and the target value are set. The sum with the value φms is zero.

  The bridge-type balanced circuit 160 shifts the resonance frequency of the coil 131 based on the control signal input from the control unit 152 so that the phase difference output from the phase comparison unit 151 becomes the target value φms. The circuit configuration and operation of the bridge-type balanced circuit 160 will be described later with reference to FIGS.

  The power receiving side resonance frequency control unit CTj includes a target value setting unit 243, a phase comparison unit 251, a control unit 252, and a bridge type balanced circuit 260. The bridge type balanced circuit 260 is an example of a first bridge circuit. The phase comparison unit 251 is an example of a first phase detection unit. The control unit 252 is an example of a first resonance frequency control unit.

  Control unit 252 sets and stores target value φmj of phase difference Δφj. As described later, for example, a value obtained by adding “−π / 2” to the target value φms in the power transmission side control unit 14 is set as the target value φmj. That is, “−3π / 2” is set as the target value φmj. Alternatively, a value obtained by adding an appropriate correction value b thereto is set. The method for setting the target value φmj is the same as that for the target value φms.

  The configuration and operation of each unit of the power receiving side resonance frequency control unit CTj are the same as the configuration and operation of each unit of the power transmission side resonance frequency control unit CTs described above.

  The power transmission side control unit 14, the power reception side control unit 24, the resonance frequency control units CTs, CTj, etc. in the power transmission systems 100, 100B can be realized by software or hardware, or a combination thereof. is there. For example, a computer including a CPU, a memory such as a ROM and a RAM, and other peripheral elements may be used to cause the CPU to execute an appropriate computer program. In that case, an appropriate hardware circuit may be used in combination.

  FIG. 4 is a diagram illustrating a circuit configuration of the bridge type balanced circuit 160.

  The bridge type balanced circuit 160 includes terminals 161 and 162, a comparator 163, switch elements SW1, SW2, SW3 and SW4, resistors R2 and R3, and a capacitor C3.

  The switch elements SW1, SW2, SW3, and SW4 are connected in an H-bridge type, and the middle point of the switches SW1 and SW2 is a node N1, and the middle point of the switches SW3 and SW4 is N2. The switches SW1 and SW3 are connected to the terminal 161, and the switches SW2 and SW4 are connected to the terminal 162.

  One end of a resistor R3 and a capacitor C3 is connected to the node N1 through a resistor R2. Resistor R3 and capacitor C3 are connected in parallel to each other. The other ends of the resistor R3 and the capacitor C3 are grounded.

  The switch elements SW <b> 1 to SW <b> 4 are controlled to be turned on / off by a control signal input from the control unit 152.

  The terminal 161 is connected to one end of the capacitor 132 (the right terminal in FIG. 4). The other end (left terminal in FIG. 4) of the capacitor 132 is connected to one end (upper terminal in FIG. 4) of the coil 131. The terminal 162 is connected to the other end of the coil 131 (the lower terminal in FIG. 4).

  The comparator 163 has a non-inverting input terminal connected between the terminal 162 and the switches SW2 and SW4, and the inverting input terminal is grounded. A voltage value representing the coil current ICOIL flowing through the coil 131 is input to the non-inverting input terminal of the comparator 163.

  The output terminal of the comparator 163 is connected to the control unit 152, and the comparator 163 is input to the non-inverting input terminal. The comparator 163 inputs a gate signal Gate representing a comparison result between the voltage value representing the coil current ICOIL and the ground potential to the control unit 152.

  In such a bridge-type balanced circuit 160, the duty ratio of the control signals SW1 to SW4 input from the control unit 152 to the switch elements SW1 to SW4 is 50%, and the control signals SW1 and SW4, the control signals SW2 and SW3, Is controlled so that the output of the phase comparator 151 becomes zero.

  However, in the present embodiment, the resonance frequency of the coil 131 is shifted so that the output of the phase comparison unit 151 becomes the target value φms by shifting the equilibrium operating point of the bridge-type balanced circuit 160.

  4 shows the circuit configuration of the bridge-type balanced circuit 160, the circuit configuration of the bridge-type balanced circuit 260 (see FIGS. 2 and 3) is the same. In the case of the bridge type balanced circuit 260, the capacitor 222 and the coil 22 are connected instead of the capacitor 131 and the coil 132, and the switch elements SW1 to SW4 are driven by the control signals SW1 to SW4 output from the control unit 252. . For this reason, the drawing of the circuit configuration of the bridge-type balanced circuit 260 is omitted here.

  5 to 7 are diagrams showing waveforms of the control signals SW1 to SW4 that drive the bridge-type balanced circuit 160 of the present embodiment.

  FIG. 5 shows the gate signal Gate and the control signals SW1 to SW4. The gate signal Gate shown in FIG. 5 has a signal level obtained by binarizing the sine waveform of the coil current ICOIL having a predetermined resonance frequency flowing through the coil 131 into an H level ('1') and an L level ('0'). For this reason, the gate signal Gate is a signal having a duty ratio of 50%.

  The control unit 152 includes a phase shifter circuit, and control signals SW2 and SW3 obtained by delaying the phase of the Gate signal by 90 degrees, and control signals SW1 and SW4 obtained by inverting the control signals SW2 and SW3, respectively. Is output.

  The control signals SW1 to SW4 shown in FIG. 5 are those when the duty ratio is 50% as in the case of the gate signal Gate, and the phase difference between the control signals SW1 and SW4 and the control signals SW2 and SW3 is 180 degrees. is there. This represents the control signals SW1 to SW4 when the control is performed so that the output of the phase comparison unit 151 becomes zero.

  The bridge type balance circuit 160 simultaneously controls on / off of the switch elements SW1 and SW4 based on the control signals SW1 and SW4, and switches on and off of the switch elements SW2 and SW2 based on the control signals SW2 and SW3. SW1 and SW4 are circuits that converge to an equilibrium operating point determined by the duty ratio or phase of the control signals SW1 to SW4 by controlling them simultaneously in opposite phases.

  In the first embodiment, when the duty ratio of the control signals SW1 to SW4 is 50%, the operating point of the bridge type balanced circuit 160 is the balanced operating point realized by the control signals SW1 to SW4 having the duty ratio of 50%. By converging, the output of the phase comparison unit 151 becomes zero.

  When the duty ratio of the control signals SW1 to SW4 is 50% ± Δ% (Δ ≠ 0%), the bridge is connected to the equilibrium operating point realized by the control signals SW1 to SW4 having the duty ratio of 50% ± Δ%. The operating point of the mold balancing circuit 160 converges. The equilibrium operating point when the duty ratio is 50% ± Δ% is different from the equilibrium operating point when the duty ratio is 50%.

  In the first embodiment, control is performed so that the output of the phase comparison unit 151 becomes the target value φms by setting the duty ratio of the control signals SW1 to SW4 to 50% ± Δ% and shifting the equilibrium operating point. .

  FIG. 6 shows waveforms of the control signals SW1 to SW4 in which the duty ratio is changed while fixing the phase difference with respect to the gate signal Gate.

  As shown enlarged on the right side of FIG. 6, the control unit 152 changes the duty ratio of the control signals SW1 to SW4. As a result, the ratio of the on / off periods of the switch elements SW1 to SW4 of the bridge-type balanced circuit 160 changes, and the resonance frequency of the coil 131 can be shifted. In the present embodiment, the control unit 152 changes the duty ratio of the control signals SW1 to SW4 so that the output of the phase comparison unit 151 becomes the target value φms.

  FIG. 7 shows waveforms of the control signals SW1 to SW4 in which the phase difference is changed while the duty ratio is fixed to 50% with respect to the gate signal Gate.

  As shown enlarged on the right side of FIG. 7, the control unit 152 changes the phases of the control signals SW <b> 1 to SW <b> 4. As a result, the on / off timing of the switch elements SW1 to SW4 of the bridge-type balanced circuit 160 changes, and the resonance frequency of the coil 131 can be shifted. In the present embodiment, the control unit 152 changes the duty ratio of the control signals SW1 to SW4 so that the output of the phase comparison unit 151 becomes the target value φms.

  In the present embodiment, the control unit 152 changes the duty ratio or the phase difference of the control signals SW1 to SW4 with respect to the gate signal Gate so that the output of the phase comparison unit 151 becomes zero as described above. Control is performed so that the output of the phase comparator 151 shifts to an operating point at which the target value φms is obtained.

  Next, the operation of resonance frequency control in the power transmission system 100B will be described with reference to FIGS.

  8 to 11, in each figure (A), the horizontal axis represents the frequency f [MHz] of the AC power supply 11, and the vertical axis represents the magnitude [dB] of the current I flowing through each coil. In each figure (B), the horizontal axis represents the frequency f [MHz] of the AC power supply 11, and the vertical axis represents the phase φ [radian] of the current I flowing through each coil. 8A to 11 correspond to FIGS. 8A and 11B. FIG.

  The phase φ indicates the phase difference Δφ with reference to the phase φvs of the voltage Vs of the AC power supply 11, that is, the phase φvs of the voltage Vs supplied to the power supply coil 12. That is, the phase φ becomes 0 when it coincides with the phase φvs.

  The symbols CAA1-4, CAB1-4, CBA1-4, CBB1-4, CCA1-4, CCB1-4, CDA1-4, CDB1-4 attached to each curve, These correspond to the power supply coil 12, the power transmission resonance coil 13, the power reception resonance coil 22, and the power extraction coil 23, respectively.

  In the resonance frequency control, the power transmission resonance coil 13 or the power transmission resonance coil 13 and the power reception resonance coil 22 are controlled so that the resonance frequencies fs and fj thereof are 10 MHz.

  8 to 11 show the results of computer simulation under such conditions.

  FIG. 8 shows a case where the resonance frequency control is performed only by either the power transmission side control unit 14 or the power transmission device 3, and FIG. 9 shows the power transmission side control unit 14 or the power transmission device 3 and the power reception side control unit 24 or the power reception device 4. The case where resonance frequency control is performed by both is shown.

  In FIG. 8, the resonance frequency control is performed on the power transmission resonance coil 13 so that the resonance frequency fs is 10 MHz. In this case, the frequency fd of the AC power supply 11 is set to 10 MHz, and “−π” is set as the target value φms.

  As indicated by the curve CAA2, the current Is of the power transmission resonance coil 13 is maximum at 10 MHz that matches the frequency fd of the AC power supply 11.

  As shown by the curve CAB2, the phase φis of the current Is of the power transmission resonance coil 13 is −π at 10 MHz which is the resonance frequency fs. That is, it matches the target value φms.

  Further, the power transmission resonance coil 13 can be viewed as a series resonance circuit when viewed from the power supply coil 12. Therefore, it becomes capacitive at a frequency fd lower than the resonance frequency fs and approaches -π / 2, and becomes inductive at a high frequency fd and approaches -3π / 2.

  Thus, the phase φis of the current Is flowing through the power transmission resonance coil 13 changes greatly in the vicinity of the resonance frequency fs. By controlling the phase φis, that is, the phase difference Δφs to be −π, the resonance frequency fs of the power transmission resonance coil 13 can be matched with the frequency fd of the voltage Vs with high accuracy.

  As indicated by the curve CAA1, the current I flowing through the power supply coil 12 is also maximum at the resonance frequency fs. As shown by the curve CAB1, the phase φi of the current I flowing through the power supply coil 12 becomes 0 or a leading phase in the vicinity of the resonance frequency fs, and becomes −π / 2 when it deviates from the resonance frequency fs.

  In FIG. 9, the resonance frequency control is performed on the power transmission resonance coil 13 and the power reception resonance coil 22 so that the resonance frequencies fs and fj thereof are 10 MHz. In this case, “−π” is set as the target value φms, and “−3π / 2” is set as the target value φmj.

  That is, the target value φmj is set to a value “φms−π / 2” obtained by adding −π / 2 to the target value φms, that is, a phase delayed by π / 2 from the target value φms.

  The curve CBA2 and the curve CBB2 are substantially the same as the curve CAA2 and the curve CAB2 in FIG.

  As indicated by the curve CBA3, the current Ij of the power receiving resonance coil 22 is maximum at 10 MHz that matches the frequency fd of the AC power supply 11.

  As indicated by the curve CBB3, the phase φij of the current Ij of the power receiving resonance coil 22 is −3π / 2 at 10 MHz which is the resonance frequency fs. That is, it matches the target value φmj. Further, when the frequency fd becomes lower than the resonance frequency fs, the phase difference Δφ decreases to approach −π / 2, and when the frequency fd becomes higher than the resonance frequency fs, the phase difference Δφ increases to −5π. / 2, that is, approaches -π / 2.

  Thus, the phases φis and φij of the currents Is and Ij flowing through the power transmission resonance coil 13 and the power reception resonance coil 22 change greatly in the vicinity of the resonance frequencies fs and fj. By controlling the phases φis and φij, that is, the phase differences Δφs and Δφj to be −π or −3π / 2, the resonance frequencies fs and fj of the power transmission resonance coil 13 and the power reception resonance coil 22 are increased to the frequency fd of the voltage Vs. Can be matched with accuracy.

  Thus, according to the power transmission systems 100 and 100B of the first embodiment, the resonance frequencies of the power transmission coil SC and the power reception coil JC can be controlled at high speed and accurately in real time.

  As a result, the resonance frequency of the power transmission coil SC and the power reception coil JC can be exactly matched to the frequency fd of the AC power supply 11, and the maximum power can always be transmitted from the power transmission device 3 to the power reception device 4. It is.

Therefore, even if there are changes in environmental factors, the maximum power can always be transmitted, and energy can be transmitted with high efficiency.

  Further, according to the resonance frequency control method of the first embodiment, the control is performed based on the phase difference Δφ of the coil current with respect to the voltage Vs of the AC power supply, so that the influence due to the fluctuation of the current amplitude is affected as in the case of the sweep search method. Accurate control can be performed without receiving.

  In the sweep search method, for example, L or C in the power transmission coil SC or the power reception coil JC is swept, and the position where the coil current value is maximum (peak) is searched by trial and error.

However, in the case of such a sweep search method, the following problem can be considered. That is, (1) since the current value of the coil always varies depending on the use state, a false detection occurs due to the variation (amplitude variation) of the coil current value, and it is not easy to perform accurate adjustment.
(2) A reciprocating sweep operation is required for adjustment, and time is required for adjustment, and high-speed real-time control is difficult. Even if the adjustment is performed once, it is necessary to adjust again if the use environment changes. Therefore, the use must be suspended each time.

  However, according to the resonance frequency control method of the first embodiment, since the control is performed in real time, the frequency fd of the AC power supply 11 and fluctuations such as environmental factors are always corrected, and the sweep search method is used. There is no need for readjustment or pause.

  Moreover, in the power transmission systems 100 and 100B of the first embodiment, when the Q values of the power transmission resonance coil 13 and the power reception resonance coil 22 are high, the sensitivity to the resonance frequency shift between the two coils becomes high.

  However, according to the resonance frequency control method of the first embodiment, since the Q value is increased, the rate of change in the vicinity of the resonance frequency of the phases φis and φij is increased, thereby increasing the control sensitivity. As a result, the phase differences Δφs and Δφj can be matched with the target values φms and φmj with higher accuracy, and higher efficiency power transmission can be performed by increasing the Q value.

  Next, the resonance frequency control (bimodal resonance control) when the coupling between the power transmission coil SC and the power receiving coil JC is increased and the bimodal characteristics appear will be described.

FIG. 10 shows the states of the currents Is and Ij and the phases φis and φij when the bimodal characteristics appear and the bimodal resonance control is not performed.

  That is, the state shown in FIG. 10 appears when the power receiving coil JC approaches the power transmitting coil SC and the coupling becomes large when operating in the state shown in FIG. 9, for example.

  In FIG. 9, what is a single peak as shown by curves CBA2, CBA3 is a double peak as shown by curves CCA2 and CCA3 in FIG. As a result, at the resonance frequency of 10 MHz, as indicated by the curve CCA4, the current extracted from the power extraction coil 23 decreases, and the transmission power decreases.

  Therefore, in the bimodal resonance control, the resonance frequencies of the power transmission coil SC and the power reception coil JC are shifted so that one of the two peaks appears at 10 MHz which is the resonance frequency fs.

  Therefore, in the normal resonance frequency control, “−3π / 2” is set as the target value φmj, but in the bimodal resonance control, the phase obtained by adding −π / 2 as the target value φmj, that is, only π / 2. “−2π” which is a delayed phase is set. That is, the target value φmj is switched from “−3π / 2” to “−2π”.

  Thus, in the bimodal resonance control, “−2π” is set as the target value φmj.

  The target value φms remains “−π” and does not change. Therefore, the difference between the target value φms and the target value φmj is switched from −π / 2 to −π by the bimodal resonance control.

  In FIG. 11, the phase φis of the current Is of the power transmission resonance coil 13 is −π at 10 MHz, which is the resonance frequency fs, as indicated by the curve CDB2. Further, as indicated by the curve CDB3, the phase φij of the current Ij of the power receiving resonance coil 22 is −2π at 10 MHz which is the resonance frequency fs.

  As shown by the curves CDA2, CDA3 and CDA4, all the currents I are increased by the bimodal resonance control. For example, in the curve CDA4, the current that is about −30 dB in the normal resonance frequency control is about −20 dB in the bimodal resonance control, which is increased by about 10 dB.

  FIG. 12 shows a change state of electric power extracted from the electric power extraction coil 23 when the distance between the power transmission resonance coil 13 and the electric power reception resonance coil 22 is changed between 200 mm and 100 mm.

  FIG. 12 shows the result of simulation with the coil diameter of 100 mm, the interval between the power supply coil 12 and the power transmission resonance coil 13 being 50 mm, and the interval between the power reception resonance coil 22 and the power extraction coil 23 being 40 mm. . A 10Ω resistor was connected as the device 21 which is a load of the power extraction coil 23.

  In FIG. 12, a curve CU1 indicates a case where normal resonance frequency control and bimodal resonance control are switched, and a curve CU2 indicates a case where bimodal resonance control is not performed.

  When the bimodal resonance control is not performed, the power decreases as the distance between the coils approaches, as indicated by the curve CU2. On the other hand, as shown by the curve CU1, when switching to the bimodal resonance control when the distance between the coils approaches about 140 mm, the power does not decrease but increases instead.

  Various methods are conceivable as a method for automatically switching between normal resonance frequency control and bimodal resonance control.

  For example, as shown in FIG. 15, the control unit 252 is provided with a target value setting unit 243C and a bimodal detection unit 245, and the target value setting unit 243C has a target value φmj1 for normal resonance frequency control and a bimodal resonance. The target value φmj2 for control is stored. And the double peak detection part 245 for detecting that the double peak characteristic appeared is provided.

  The target value setting unit 243C outputs the target value φmj1 as the target value φmj in the normal resonance frequency control, but outputs the target value φmj2 as the target value φmj when the bimodal detection unit 245 outputs the detection signal S1. . As a result, normal resonance frequency control and bimodal resonance control are automatically switched.

  Note that the twin peak detection unit 245 may detect, for example, that the transmission power is lower than a predetermined amount or that the distance of the power receiving coil JC is closer than a predetermined value. Alternatively, the two target values φmj1 and φmj2 may be switched and output at an appropriate timing, and the target value φm with the larger power may be selected.

  Next, resonance frequency control in the power transmission systems 100 and 100B of the first embodiment will be described with reference to flowcharts.

  In FIG. 16, the phase φvs of the AC power supply 11 is detected (# 11), the phases φis and φij of the power transmission resonance coil 13 and the power reception resonance coil 22 are detected (# 12), and the phase differences Δφs and Δφj are obtained (# 13). ).

  Then, feedback control is performed so that the phase differences Δφs and Δφj coincide with the target values φms and φmj (# 14).

  In FIG. 17, in the feedback control, the target values φmj2 and φmj1 are switched (# 22, 23) depending on whether or not a bimodal characteristic appears (# 21).

  As described above, by performing the bimodal resonance control when the bimodal characteristic appears, it is possible to suppress a decrease in transmission power and to improve the efficiency of power transmission.

  Power transmission systems 100 and 100B of the first embodiment include power supply coil 12 and power transmission resonance coil 13, power reception resonance coil 22 and power extraction coil 23. Here, the resonance frequency when power is transmitted by magnetic field resonance between the power transmission resonance coil 13 and the power reception resonance coil 22 without the power supply coil 12 and the power extraction coil 23 is actually the power supply coil 12. And the power extraction coil 23, unlike the resonance frequency when power is transmitted by magnetic field resonance between the power transmission resonance coil 13 and the power reception resonance coil 22, a bimodal characteristic appears due to this difference.

  In the first embodiment, the power supply coil 12 and the power take-out coil 23 do not exist, and the actual resonance frequency from the optimum resonance frequency when power is transmitted by magnetic field resonance between the power transmission resonance coil 13 and the power reception resonance coil 22 is actually determined. When the power supply coil 12 and the power take-out coil 23 are present, the resonance condition is changed to an optimum resonance frequency when power is transmitted between the power transmission resonance coil 13 and the power reception resonance coil 22 by magnetic field resonance. This improves the efficiency of power transmission.

  In the first embodiment, the resonance frequency can be varied by shifting the equilibrium operating point of the bridge-type balanced circuit 160. The bridge-type balanced circuit 160 is a simple circuit that can be realized by a bridge circuit including switch elements SW1 to SW4, a resistor, and a capacitor.

  For this reason, according to Embodiment 1, the efficiency of electric power transmission can be improved by changing the resonance frequency with a simple configuration.

  In the first embodiment, the maximum power is always transmitted from the power transmission device 3 to the power reception device 4 by switching between normal resonance frequency control and bimodal resonance control when the bimodal characteristics appear. Energy transmission with high efficiency.

  In each Embodiment 1 described above, −π is set as the target value φms, and −3π / 2 or −2π is set as the target value φmj. “−π” set as the target value φms is an example of the target value “β”. Further, “−3π / 2” and “−2π” set as the target value φmj are examples of the target values “β−π / 2” and “β−π”, respectively.

  These target values φms and φmj can be variously changed according to the configurations of the power transmission side control unit 14, the power reception side control unit 24, the feedback control units 144 and 244, and the resonance frequency control units CTs and CTj.

  In the first embodiment, the phase and the phase difference are expressed in radians. When the phase or phase difference is α [radian], this is equivalent to (α + 2nπ) [radian]. n is an arbitrary integer. Also, the phase and phase difference may be expressed in degrees instead of radians.

  In addition, it has been described that the correction values a and b may be added to the target values φms and φms when they are set. Such correction values a and b may be determined so that, for example, the maximum power is actually obtained.

  In the first embodiment described above, the configurations of the phase detection units 141 and 142 can be variously changed. That is, it may be a voltage waveform or a current waveform, or a value or data indicating a phase. That is, it may be a signal or data including phase information about the voltage Vs or the current Is.

  In the first embodiment described above, the adding unit 152 and the gain adjusting unit 153, and the adding unit 252 and the gain adjusting unit 253 are examples of calculating units, respectively. Although the MEMS variable capacitance device which is the capacitors 132 and 222 is driven by the drivers 156 and 256, other types of capacitors may be driven. Further, the driver 156 may be driven so as to vary the inductance of the coil instead of the capacitor.

  In the first embodiment described above, the power transmission system coil SC, the power reception system coil JC, the power transmission side control unit 14, the power reception side control unit 24, the feedback control units 144 and 244, the resonance frequency control units CTs and CTj, and the power transmission device 3 The configuration, the structure, the circuit, the shape, the number, the arrangement, etc. of each part or the whole of the power receiving device 4 and the power transmission systems 100 and 100B can be appropriately changed in accordance with the gist of the present invention.

  The power transmission system (power transmission device) 100, 100B of the first embodiment described above is charged with a secondary battery built in a mobile device such as a mobile phone, a mobile computer, and a portable music player, or an automobile. It can be applied to the charging of secondary batteries of transportation equipment such as.

  In the above description, the bridge-type balanced circuit 160 as shown in FIG. 4 is used as an example of the bridge circuit. However, the bridge-type balanced circuit includes a bridge circuit and can adjust the resonance frequency. It is not limited to the circuit configuration of the bridge type balanced circuit 160 shown in FIG.

  Further, in the above, the control is performed so that the output of the phase comparison unit 151 becomes the target value φms by changing the duty ratio of the control signals SW1 to SW4 input to the bridge type balance circuit 160 and shifting the balance operation point. Explained.

  However, instead of changing the duty ratio of the control signals SW1 to SW4 as shown in FIG. 6, the same control can be performed by changing the phase of the control signals SW1 to SW4 as shown in FIG.

  When the control signals SW2 and SW3 obtained by delaying the phase of the Gate signal by 90 degrees and the control signals SW1 and SW4 obtained by inverting the control signals SW2 and SW3, respectively, the equilibrium operating point of the bridge type equilibrium circuit 160 is the initial value. The state becomes an equilibrium state, and the output of the phase comparator 151 becomes zero. In this case, the duty ratio of the control signals SW1 to SW4 is 50%.

  When the phase of the control signals SW1 to SW4 is shifted from the above-described phase, the balanced operation point of the bridge type balanced circuit 160 is shifted from the equilibrium operation point in the initial state, so that the output of the phase comparator 151 is zero. Disappear.

  Therefore, the control may be performed so that the output of the phase comparison unit 151 becomes the target value φms by changing the phases of the control signals SW1 to SW4.

  In the above description, the mode in which the control is performed so that the output of the phase comparison unit 151 becomes the target value φms by shifting the duty ratio or phase of the control signals SW1 to SW4 from the duty ratio or phase of the Gate signal. The control may be performed so that the output of the phase comparison unit 151 becomes the target value φms by shifting the duty ratio and phase of the control signals SW1 to SW4 from the duty ratio and phase of the Gate signal.

  Further, in the above, the power transmission system SC of the power transmission system 100 includes the power supply coil 12 and the power transmission resonance coil 13, the power reception system coil JC includes the power reception resonance coil 22 and the power extraction coil 23, and the bridge-type balanced on the power transmission side. The embodiment including the circuit 160 and the bridge-type balanced circuit 260 on the power receiving side has been described.

  However, in the power transmission system 100, the power transmission system coil SC includes the power supply coil 12 and the power transmission resonance coil 13, the power reception system coil JC includes only the power reception resonance coil 22, and the bridge-type balanced circuit has a power transmission side bridge. A configuration including only the mold balancing circuit 160 may be adopted. That is, a configuration in which power is directly extracted from the power reception resonance coil 22 without including the power extraction coil 23 and the bridge-type balanced circuit 260 on the power reception side is removed may be employed.

  In the case of such a configuration, the resonance frequency of the coil 131 is set so that the phase difference output from the phase comparison unit 151 becomes the target value φms when the bridge-type balanced circuit 160 shifts the balanced operation point on the power transmission side. Will be shifted.

  On the contrary, in the power transmission system 100, the power transmission system coil SC includes only the power transmission resonance coil 13, the power reception system coil JC includes the power reception resonance coil 22 and the power extraction coil 23, and the power receiving side bridge-type balanced The embodiment including the circuit 260 has been described. That is, the power supply coil 12 may not be included and power may be directly supplied from the AC power supply 11 to the power transmission resonance coil 13 and the power transmission side bridge-type balanced circuit 160 may be removed.

  In the case of such a configuration, on the power receiving side, the bridge-type balanced circuit 260 shifts the equilibrium operating point, so that the phase difference output from the phase comparison unit 251 becomes the target value φmj. The resonance frequency will be shifted.

<Embodiment 2>
FIG. 18 is a diagram illustrating an example of a system including an apparatus including a strongly coupled non-contact power transmission device and a power reception device according to the second embodiment. The system including the power transmission device 1 and the plurality of devices 2a, 2b, and 2c including the power reception device illustrated in FIG. 18 uses the magnetic field resonance or the electric field resonance to transmit the devices 2a, 2b, and 2c, respectively. It is a system that supplies power to Further, by using the system shown in FIG. 18, even when the devices 2a, 2b, and 2c have different charging power (or received power), the balance of receiving power by the devices 2a, 2b, and 2c is adjusted. Can be charged at the same time.

  The power transmission device 1 illustrated in FIG. 18 includes a power supply unit 3, a power supply coil 4, and a power transmission resonance coil 5. In addition, each of the devices 2a, 2b, and 2c shows power receiving resonance coils 6a, 6b, and 6c, power extraction coils 7a, 7b, and 7c, and loads ZLa, ZLb, and ZLc, respectively. Details of the power transmission device 1 and the devices 2a, 2b, and 2c will be described later.

  The power supply coil 4, power transmission resonance coil 5, power reception resonance coils 6a, 6b, and 6c, and power extraction coils 7a, 7b, and 7c for the devices 2a, 2b, and 2c including the power transmission device 1 and the power reception device with reference to FIG. A case where power transmission and reception are performed by using will be described. The power supply unit 3 of the power transmission device 1 supplies power to the power transmission resonance coil 5 via the power supply coil 4. The power supply unit 3 includes, for example, an oscillation circuit, and uses electric power supplied from an external power supply (not shown) at a resonance frequency that generates resonance between the power transmission resonance coil 5 and the power reception resonance coils 6a, 6b, and 6c. Supply to the supply coil 4.

  The power supply coil 4 may be a circuit that supplies power supplied from the power supply unit 3 to the power transmission resonance coil 5 by electromagnetic induction. In addition, the power supply coil 4 and the power transmission resonance coil 5 are disposed at positions where power can be supplied by electromagnetic induction.

  The power transmission resonance coil 5 may be a circuit having a helical coil, for example. Instead of a helical coil, a combination of a spiral coil and a capacitor is also conceivable. Further, the power transmission resonance coil 5 can be represented by an LC resonance circuit, and the resonance frequency (power transmission frequency f0) of the power transmission resonance coil 5 can be expressed by Expression 1.

f0 = 1 / 2π√LC Equation 1
f0: Resonance frequency of the power transmission resonance coil L: Inductance of the power transmission resonance coil C: Capacitance of the power transmission resonance coil √LC: 1/2 power of (LC) The power reception resonance coils 6a, 6b, 6c can change the inductance, for example It is conceivable that the circuit has a coil or a capacitor whose capacitance is variable, and the resonance frequency of each of the power receiving resonance coils 6a, 6b, 6c can be varied. Each of the power receiving resonance coils 6a, 6b, and 6c can be expressed by an LC resonance circuit, and the resonance frequency f1 of the power receiving resonance coil can be expressed by Expression 2.

f1 = 1 / 2π√Lvr ・ Cvr Equation 2
f1: Resonance frequency of the power receiving resonance coil Lvr: Inductance of the power receiving resonance coil Cvr: Capacitance of the power receiving resonance coil √LC: 1/2 power of (Lvr · Cvr) Each of the power extraction coils 7a, 7b, 7c has a corresponding power receiving resonance A circuit for extracting electric power from each of the coils 6a, 6b, 6c by electromagnetic induction is conceivable. Note that the power extraction coils 7a, 7b, and 7c corresponding to the power receiving resonance coils 6a, 6b, and 6c are arranged at positions where power can be supplied by electromagnetic induction.

  The loads ZLa, ZLb, ZLc are connected to the power extraction coils 7a, 7b, 7c, respectively. Each of the loads ZLa, ZLb, and ZLc is, for example, a battery or an electronic device. Actually, a rectifier circuit, an AC-DC converter, or the like for converting alternating current into direct current is connected to the previous stage of the loads ZLa, ZLb, ZLc. Further, a voltage converter that converts the voltage into a predetermined voltage value, a transformer, a detection circuit that monitors the charge amount, and the like may be connected.

  The variable resonance frequency of the power receiving resonance coils 6a, 6b, 6c will be described.

  When there is only one device to be charged by the power transmission device 1, for example, when there is only the device 2a in FIG. 18, the power transmission frequency f0 of the transmitted power transmitted from the power transmission device 1 and the transmission power possessed by the device 2a are received. The resonance frequency f1 of the power reception resonance coil (LC resonance circuit) of the power reception device is made the same. Thereafter, the power transmission device 1 transmits power that can be supplied to the device 2a.

  Moreover, when the several apparatus charged with the power transmission apparatus 1 is the same charging power, for example, when the apparatus 2a, the apparatus 2b, and the apparatus 2c are the same charging power, each of the apparatus 2a, the apparatus 2b, and the apparatus 2c The resonance frequency f1 of the resonance circuit and the power transmission frequency f0 are the same. Thereafter, the power transmission device 1 transmits power that can be supplied to the devices 2a, 2b, and 2c. When a plurality of devices have the same charging power, the power transmission device 1 transmits power that can be supplied to all the devices. In this example, the power transmission device 1 transmits power for three devices, the device 2a, the device 2b, and the device 2c.

  Next, a case where a plurality of devices charged by the power transmission device 1 have different charging power, for example, a case where the devices 2a, 2b, and 2c have different charging power will be described. The resonance frequency f1 of the device with the maximum charging power among the devices 2a, 2b, and 2c is set to be the same as the power transmission frequency f0. The resonance frequency of a device other than the device with the maximum charging power is set to a resonance frequency determined according to the power required for charging each device, and the balance of power transfer is adjusted. Thereafter, the power transmission device 1 transmits power to each device. When a plurality of devices have different charging power, the power transmission device 1 transmits power necessary for charging corresponding to each device. In this example, the power transmitted by the power transmission device 1 is the sum of the charging power corresponding to each of the devices 2a, 2b, and 2c.

  Note that it is difficult to make the power transmission frequency f0 and the resonance frequency f1 completely coincide with each other in an actual circuit, so that the power transmission frequency f0 and the resonance frequency f1 are within a predetermined frequency range. Will be considered the same.

  The power transmission device 1 will be described with reference to FIG.

  FIG. 19 is a diagram illustrating an example of hardware of the power transmission device. The power transmission device 1 illustrated in FIG. 19 includes a control unit 321, a storage unit 322, a communication unit 323, an antenna 324, a power supply unit 325, and a power transmission unit 326. As the power transmission device 1, for example, a flat charging stand represented by a resonance-type charging pad can be considered. In addition, each of the one or more devices arranged for charging on the power transmission resonance coil of the power transmission unit 326 of the power transmission device 1 and within the range surrounded by the power transmission resonance coil has a substantially constant power via the power transmission resonance coil. Can be received. This is because the relative positional relationship between the power transmission resonance coil and the power reception resonance coil of the device can be approximated to be the same regardless of the position of the power reception resonance coil on the power transmission resonance coil and the range surrounded by the power transmission resonance coil.

  In addition, the power transmission device 1 can vary the power of the power transmission source below the maximum transmission power.

  The control unit 321 controls each unit of the power transmission device 1. In addition, the control unit 321 acquires identification information for identifying the devices 2a, 2b, and 2c and information indicating charging power associated with the devices 2a, 2b, and 2c from each of the devices. The control unit 321 uses each of the acquired identification information to vary the combination of devices and the resonance frequency or Q value of the resonance circuit included in the power receiving unit 335 of each device associated with the combination. The control unit 321 refers to combination information having variable information of each device associated with each combination of one or more devices and each of the one or more device combinations, and uses each acquired identification information to Select variable information associated with each. The variable information is used to transmit the resonance frequency of the resonance circuit of the device having the maximum charging power by changing the resonance frequency or Q value of the resonance circuit of the power receiving unit of each device by using a combination of one or more devices. Use frequency. In addition, using variable information, it is possible to charge each charging power corresponding to each device other than the device with the largest charging power by using the resonance frequency or Q value of the resonance circuit of the power receiving unit of each device other than the device with the largest charging power. Variable resonance frequency or Q value. Subsequently, for example, the control unit 321 refers to each efficiency associated with the identification information using each of the acquired identification information, and determines the transmission power using the charging power and the efficiency corresponding to each of the acquired devices. Ask.

  The control unit 321 may be a central processing unit (CPU), a multi-core CPU, or a programmable device (such as a field programmable gate array (FPGA) or a programmable logic device (PLD)).

  The storage unit 322 stores power reception information, efficiency information, combination information, and the like, which will be described later. The storage unit 322 may be, for example, a memory such as a read only memory (ROM) or a random access memory (RAM), a hard disk, or the like. The storage unit 322 may record data such as parameter values and variable values, or may be used as a work area at the time of execution.

  The communication unit 323 is an interface that is connected to the antenna 324 and performs communication such as wireless communication with the communication unit 333 of the power receiving apparatus. For example, an interface for performing wireless connection such as a wireless local area network (LAN) or Bluetooth (registered trademark) can be considered. The communication unit 323 transmits variable information for changing the resonance frequency of the resonance circuit of the power reception unit to the power transmission frequency to the device having the maximum charging power. In addition, the communication unit 323 can charge the resonance frequency of the resonance circuit of the power receiving unit for each device other than the device with the largest charging power according to each charging power corresponding to each device other than the device with the largest charging power. Variable information that changes to the resonance frequency or Q value is transmitted to each device.

  The power supply unit 325 includes the power supply unit 3 and the power supply coil 4 when performing power transmission using the power supply coil 4 and the power transmission resonance coil 5 described in FIG. 18.

  When the power supply coil 4 is not used, the power supply unit 3 directly supplies power to the power transmission resonance coil 5. The power supply unit 3 includes, for example, an oscillation circuit and a power transmission amplifier. The oscillation circuit generates a resonance frequency f0. The power transmission amplifier inputs power supplied from the external power source to the power transmission resonance coil 5 at a frequency generated by the oscillation circuit. Further, the resonance frequency of the oscillation circuit may be varied, and the variable control may be performed by the control unit 321.

  The power transmission unit 326 includes the power transmission resonance coil 5 illustrated in FIG. Note that the resonance frequency of the coil L and the capacitor C of the LC resonance circuit of the power transmission unit 326 may be varied by using a coil whose inductance can be varied or a capacitor whose capacitance can be varied. The variable control is performed by the control unit 321. It is possible to do it.

  A device including a power receiving device will be described with reference to FIGS.

  FIG. 20 is a diagram illustrating an example of hardware of a device including a power receiving device. 20 includes a control unit 331, a storage unit 332, a communication unit 333, an antenna 334, a power reception unit 335, a charging unit 336, and a device configuration unit 337. The power receiving device is, for example, a control unit 331, a storage unit 332, a communication unit 333, an antenna 334, a power receiving unit 335, and a charging unit 336.

  The control unit 331 controls each unit of the device 2 (devices 2a, 2b, and 2c in FIG. 18). The control unit 331 generates charging information including identification information for identifying the device and information indicating the charging power associated with the device, and transmits the charging information from the device to the power transmission device 1. The control unit 331 receives, from the power transmission device 1, variable information that varies the resonance frequency or Q value of the resonance circuit included in the power reception unit 335 of the device.

  In the case of a device with the maximum charge power, the resonance frequency of the resonance circuit of the power reception unit 335 is changed to the power transmission frequency. In the case of a device other than the device with the largest charge power, the transmission power transmitted from the power transmission device 1 is the resonance frequency of the resonance circuit of the power receiving unit 335 and the charge power corresponding to the device other than the device with the largest charge power. To a frequency that can be supplied.

  The control unit 331 may be a central processing unit (CPU), a multi-core CPU, or a programmable device (such as a field programmable gate array (FPGA) or a programmable logic device (PLD)).

  A storage unit 332, charging information described later, Q value variable information, and the like are stored. The storage unit 332 may be a memory such as a read only memory (ROM) or a random access memory (RAM), a hard disk, or the like. The storage unit 332 may record data such as parameter values and variable values, or may be used as a work area at the time of execution.

  The interface is connected to the communication unit 333 and the antenna 334 and performs communication such as wireless communication with the communication unit 333 of the power transmission device 1. For example, an interface for wireless connection such as a wireless local area network (LAN) or Bluetooth can be considered.

  The power receiving unit 335 includes the power receiving resonance coils 6a, 6b, and 6c and the bridge type balanced circuit 160 shown in FIG. FIG. 21 shows a circuit of the power receiving unit 335.

  In the circuit shown in FIG. 21, the balance of power transfer is adjusted by changing the resonance frequency. That is, the resonance frequency is varied by adjusting the duty ratio or phase of the control signals SW1 to SW4 that drive the switch elements SW1 to SW4 of the bridge-type balanced circuit 160 included in the power receiving unit 335, thereby adjusting the balance of power transfer. In addition, the resonance frequency of the LC resonance circuit of the device with the maximum charging power is the same as the transmission frequency, and the resonance frequency of the LC resonance circuit of the device other than the device with the maximum charging power is varied to be different from the transmission frequency. To do.

  FIG. 21 is a diagram illustrating a circuit configuration of the power reception unit 35.

  The power receiving unit 35 includes a coil 6, a capacitor C 1, and a bridge type balanced circuit 160. The coil 6 corresponds to the coils 6a to 6c shown in FIG. The capacitor C1 is a capacitor inserted in series with the coils 6a to 6c.

  The bridge type balanced circuit 160 shifts the resonance frequency of the coil 6 based on the control signal input from the control unit 331. The bridge type balanced circuit 160 is the same as the bridge type balanced circuits 160 and 260 of the first embodiment.

  The bridge type balanced circuit 160 includes terminals 161 and 162, a comparator 163, switch elements SW1, SW2, SW3 and SW4, resistors R2 and R3, and a capacitor C3.

  The switch elements SW1, SW2, SW3, and SW4 are connected in an H-bridge type, and the middle point of the switches SW1 and SW2 is a node N1, and the middle point of the switches SW3 and SW4 is N2. The switches SW1 and SW3 are connected to the terminal 161, and the switches SW2 and SW4 are connected to the terminal 162.

  One end of a resistor R3 and a capacitor C3 is connected to the node N1 through a resistor R2. Resistor R3 and capacitor C3 are connected in parallel to each other. The other ends of the resistor R3 and the capacitor C3 are grounded.

  The switch elements SW <b> 1 to SW <b> 4 are controlled to be turned on / off by a control signal input from the control unit 331.

  The terminal 161 is connected to one end of the capacitor 132 (the right terminal in FIG. 21). The other end of the capacitor 132 (the left terminal in FIG. 21) is connected to one end of the coil 6 (the upper terminal in FIG. 21). The terminal 162 is connected to the other end of the coil 6 (the lower terminal in FIG. 21).

  The comparator 163 has a non-inverting input terminal connected between the terminal 162 and the switches SW2 and SW4, and the inverting input terminal is grounded. A voltage value representing the coil current ICOIL flowing through the coil 6 is input to the non-inverting input terminal of the comparator 163.

  The output terminal of the comparator 163 is connected to the control unit 331, and the comparator 163 is input to the non-inverting input terminal. The comparator 163 inputs a gate signal Gate representing a comparison result between the voltage value representing the coil current ICOIL and the ground potential to the control unit 331.

  In such a bridge-type balanced circuit 160, the duty ratio of the control signals SW1 to SW4 input from the control unit 331 to the switch elements SW1 to SW4 is 50%, and the control signals SW1 and SW4, the control signals SW2 and SW3, Is controlled so that the resonance frequency is equal to the power transmission frequency.

  22 to 24 are diagrams showing waveforms of the control signals SW1 to SW4 that drive the bridge-type balanced circuit 160 of the present embodiment.

  FIG. 22 shows the gate signal Gate and the control signals SW1 to SW4. The gate signal Gate shown in FIG. 22 has a signal level obtained by binarizing a sine waveform of a coil current ICOIL having a predetermined resonance frequency flowing through the coil 6 into an H level ('1') and an L level ('0'). For this reason, the gate signal Gate is a signal having a duty ratio of 50%.

  The control unit 331 includes a phase shifter circuit, and control signals SW2 and SW3 obtained by delaying the phase of the Gate signal by 90 degrees, and control signals SW1 and SW4 obtained by inverting the control signals SW2 and SW3, respectively. Is output.

  The control signals SW1 to SW4 shown in FIG. 22 are those when the duty ratio is 50% and the phase difference between the control signals SW1 and SW4 and the control signals SW2 and SW3 is 180 degrees. This represents the control signals SW1 to SW4 when the control is performed so that the resonance frequency is equal to the power transmission frequency.

  FIG. 23 shows waveforms of the control signals SW1 to SW4 in which the duty ratio is changed while fixing the phase difference with respect to the gate signal Gate.

  As shown enlarged on the right side of FIG. 23, the control unit 331 changes the duty ratio of the control signals SW1 to SW4. As a result, the ratio of the on / off periods of the switch elements SW1 to SW4 of the bridge-type balanced circuit 160 changes, and the resonance frequency of the coil 6 can be shifted. In the present embodiment, the control unit 331 changes the duty ratio of the control signals SW1 to SW4 so that the resonance frequency is different from the power transmission frequency.

  FIG. 24 shows waveforms of control signals SW1 to SW4 in which the phase difference is changed while the duty ratio is fixed to 50% with respect to the gate signal Gate.

  As shown enlarged on the right side of FIG. 24, the control unit 331 changes the phase of the control signals SW1 to SW4. As a result, the on / off timing of the switch elements SW1 to SW4 of the bridge type balanced circuit 160 changes, and the resonance frequency of the coil 6 can be shifted. In the present embodiment, the control unit 331 changes the duty ratio of the control signals SW1 to SW4 so that the resonance frequency is different from the power transmission frequency.

  In the present embodiment, the control unit 331 performs control so that the resonance frequency is different from the power transmission frequency by changing the duty ratio or phase difference of the control signals SW1 to SW4 with respect to the gate signal Gate.

  The charging unit 336 includes a power extraction coil, a rectifier circuit connected to the power extraction coil, and a battery. When receiving power using the power receiving resonance coil 6a and the power extraction coil 7a in FIG. 18 and charging the received power, the charging unit 336 includes the power extraction coil 7a, a rectifier circuit connected to the power extraction coil 7a, and a battery. ing. Similarly, when receiving power using the power receiving resonance coil 6b and the power extraction coil 7b and charging the received power, the charging unit 336 connects the power extraction coil 7b and the rectifier circuit and battery connected to the power extraction coil 7b. I have. When receiving power using the power receiving resonance coil 6c and the power extraction coil 7c and charging the received power, the charging unit 336 includes a power rectification circuit connected to the power extraction coil 7c, the power extraction coil 7c, and a battery.

  When the power extraction coil is not used, the charging unit 336 is directly connected to the power receiving resonance coil of the power receiving unit 335. In the case of the power receiving resonance coil 6a of FIG. 18, a rectifier circuit and a battery are connected to the power receiving resonance coil 6a. In the case of the power receiving resonance coil 6b, a rectifier circuit and a battery are connected to the power receiving resonance coil 6b. In the case of the power receiving resonance coil 6c, a rectifier circuit and a battery are connected to the power receiving resonance coil 6c. In this example, the rectifier circuit is used as a circuit for charging the battery of the charging unit 336, but the battery may be charged using another charging circuit.

  The device configuration unit 337 indicates a portion other than the power receiving device of the device. When the device is a mobile device, the device configuration unit 337 is a part that realizes functions other than the power receiving device of the mobile device.

  Operation | movement of the power transmission apparatus 1 is demonstrated using FIG.

  FIG. 25 is a flowchart illustrating an example of the operation of the power transmission device. In step S <b> 1, the power transmission device 1 receives a signal including charging information transmitted from the device using wireless communication or the like. The communication unit 323 transfers the charging information included in the received signal to the control unit 321. The charging information includes identification information for identifying the device and information indicating the charging power of each device. FIG. 26 is a diagram illustrating an example of a data structure of charging information, power receiving information, and efficiency information. The charging information 71a, 71b, 71c illustrated in FIG. 26 includes information stored in “ID” and “charging power”. For example, the charging information 71a is transmitted from the device 2a of FIG. 18, “A” is stored in “ID” as identification information indicating the device 2a, and “50” is expressed in “Charging power” as 50 W as the charging power of the device 2a. Is stored. For example, the charging information 71b is transmitted from the device 2b of FIG. 18, "B" is stored as identification information indicating the device 2b in "ID", and "5" indicating 5W as the charging power of the device 2b is stored in "Charging power". Is stored. For example, the charging information 71c is transmitted from the device 2c of FIG. 18, “C” is stored as the identification information indicating the device 2c in “ID”, and “3” indicating 3 W as the charging power of the device 2c is stored in “Charging power”. Is stored.

  Subsequently, in step S <b> 1, the control unit 321 stores the charging information received from each of the devices 2 a, 2 b, and 2 c in the power reception information of the storage unit 322. The power reception information includes identification information for identifying the device and information indicating the charging power of each device. The power reception information 72 illustrated in FIG. 26 includes information stored in “ID” and “charging power”. In the case of this example, the charging information 71a, 71b, 71c received from the devices 2a, 2b, 2c is stored in the power receiving information 72.

  In step S1, after receiving a signal including charging information from the device, the control unit 321 proceeds to step S2 when confirming that the signal including charging information is not transmitted from the device for a certain period. That is, the device to be charged is determined. For example, when the device 2a is arranged in the power transmission device 1, a signal including the charging information 71a is transmitted from the device 2a to the power transmission device 1, and after the power transmission device 1 receives the signal, it newly When charging information is not received, it transfers to step S2. Further, when a new signal including charging information is received from the device 2b within a certain period, the apparatus further stands by for a certain period, and when no new charging information is received after a certain period of time, the process proceeds to step S2. In addition, determination of the apparatus to charge is not limited to the said method, You may use another method.

  In step S2, the control unit 321 refers to the power reception information to determine whether or not the number of devices arranged in the power transmission device 1 is singular. If the number is singular, the process proceeds to step S3 (Yes). If so, the process proceeds to step S4 (No). For example, when referring to the power reception information 72 of FIG. 26, it is detected that the three devices 2a, 2b, and 2c are arranged in the power transmission device 1, and the process proceeds to step S4 because it is not singular.

  In step S3, the transmission power when the control unit 321 is single is set. In the case of a single transmission power, the transmission power is obtained using the charging power of the power reception information and the efficiency of the efficiency information stored in the storage unit 322. The transmitted power can be expressed by Equation 3.

Transmission power = charging power / efficiency Equation 3
An example of efficiency information is shown in efficiency information 73 of FIG. The efficiency information 73 in FIG. 26 has information stored in “ID” and “efficiency”. Further, it is used when the number of charging devices is single and when the charging power and efficiency of each of the plurality of charging devices are the same. In “ID”, information for identifying the device is stored. In this example, “A”, “B”, “C”, “D”, “E”, “F”, “G”, “H”,. “Efficiency” stores the efficiency corresponding to each device. For example, the efficiency may be obtained by using power supplied from an external power source to the power supply unit 325 of the power transmission device 1 and power supplied to the battery of the charging unit 336 of the device 2. In this example, “0.8” indicating 80%, “0.9” indicating 90%, “0.85” indicating 85%, and the like are stored as information indicating efficiency.

  For example, the control unit 321 refers to the power reception information 72 to acquire “50” indicating 50 W that is the charging power corresponding to the identification information “A”, and refers to the efficiency information 73 to correspond to the identification information “A”. "0.8" indicating 80%, which is the efficiency to be acquired, is acquired. Thereafter, charging power / efficiency is calculated to obtain transmission power 62.5W. Next, the control unit 321 sets the power output from the power supply unit 325 to be 62.5 W.

  In step S4, the control unit 321 refers to the power reception information to determine whether or not the charging powers of the plurality of devices are the same and the efficiency is the same. If they are the same, the process proceeds to step S5 (Yes). Proceeds to step S6 (No).

  In step S5, the control unit 321 sets the transmission power when the charging power of the plurality of devices is the same and the efficiency is the same. The transmission power when the charging power of a plurality of devices is the same is determined by using the charging power of the power reception information, the number of devices to be charged (number), and the efficiency of the efficiency information stored in the storage unit 322. Ask for. The transmitted power can be expressed by Equation 4.

Transmission power = (charging power / efficiency) x number of units Equation 4
For example, when the number of devices to be charged stored in the power reception information is 3, the charging power corresponding to each device is 5 W, and the efficiency is 0.8 (80%), the equation 4 is used. Thus, the transmission power of 18.75 W is obtained. Next, the control unit 321 sets the power output from the power supply unit 325 to be 18.75W.

  In step S6, the control unit 321 refers to the power reception information and selects a device other than the device with the maximum charging power. For example, a device other than the device with the maximum charging power is selected with reference to “charging information” in the power receiving information 72. In this example, since the device with the maximum charging power is the device with the identification information “A”, the devices with the identification information “B” and “C” are selected.

  In step S <b> 7, a notification for changing the resonance frequency or Q value of the power reception unit 335 of each device selected by the control unit 321 is transmitted to each device. In step S7, the control unit 321 refers to the combination information using the received identification information, and acquires variable information corresponding to the combination of devices to be charged simultaneously.

  The combination information will be described. FIG. 27 is a diagram illustrating an example of the data structure of the combination information. The combination information 81 shown in FIG. 27 is used when the duty ratios of the control signals SW1 to SW4 for driving the switch elements SW1 to SW4 of the bridge type balanced circuit 160 are varied. The combination information 81 includes information stored in “device combination”, “variable information”, and “efficiency information”. In “device combination”, a combination of devices is stored. In this example, combinations of three different devices corresponding to the identification information “A”, “B”, and “C” are stored. "A" "B" combination, "A" "C" combination, "A" "C" combination, "B" "C" combination, "A" "A" "B" combination, ... A combination of “B”, “B”, “C”,... Is stored.

  In this example, three combinations are shown, but the number is not limited to three. Here, a description will be given of a form in which the variable information represents the amount by which the duty ratio of the control signals SW1 to SW4 changes with respect to 50%. This amount of change is a portion corresponding to Δ% shown in FIG. The control signals SW <b> 1 to SW <b> 4 are control signals used for controlling on / off of the switch elements SW <b> 1 to SW <b> 4 of the bridge type balanced circuit 160 of the power receiving unit 335.

  Here, when the control signals SW1 to SW4 are at the H level, the switches SW1 to SW4 are turned on, and the duty ratio represents the ratio of the H level section in one cycle of the control signals SW1 to SW4.

“Variable information” stores information for varying the resonance frequency or Q value of each device in association with the information stored in “device combination”. That is, when the power receiving unit 335 of a plurality of devices receives power from the power transmission unit 326, the variable information is used to optimize the amount of power received by each device according to the combination of the types of the plurality of devices. This is information indicating the degree to which the resonance frequency when the power reception unit 335 receives power from the power transmission unit 326 by magnetic field resonance is varied.
In this example, “CA” “CB” “CB1” “CB2” “CB3” “CB4” “CC1” “CC2” “CC3” “CC4” “CC5” “CC6”... Are stored as variable information. ing. “CA” is an amount by which the duty ratio of the control signals SW1 to SW4 for controlling the switch elements SW1 to SW4 of the bridge type balanced circuit 160 of the power receiving unit 335 of the device corresponding to the identification information “A” changes with respect to 50%. This is a value used to set (change amount). The value indicated by “CA” is a value that makes the amount of change zero (Δ = 0%). In this case, the value for changing the resonance frequency f1 of the coil 6a to the same frequency as the power transmission frequency f0. Is shown. “CB”, “CB1”, “CB2”, “CB3”, and “CB4” are control signals SW1 to SW4 for controlling the switch elements SW1 to SW4 of the bridge type balanced circuit 160 of the power receiving unit 335 of the device corresponding to the identification information “B”. This is a value used to set the amount of change (change amount) with respect to 50% of the duty ratio. “CC1”, “CC2”, “CC3”, “CC4”, “CC5”, and “CC6” are control signals for controlling the switch elements SW1 to SW4 of the bridge-type balanced circuit 160 of the power receiving unit 335 of the device corresponding to the identification information “C”. This is a value used to set an amount (change amount) by which the duty ratio of SW1 to SW4 changes with respect to 50%. The value used to set the change amount of the device corresponding to the identification information “B” and “C” is a value that makes the resonance frequency of the coil 6 c a frequency different from the power transmission frequency f 0. That is, it is a value for changing the resonance frequency or Q value for the power transmission frequency f0 in the coil 6c. However, when the device with the maximum charging power is a device corresponding to the identification information “B”, the resonance frequency f1 of the coil 6b is varied to the same frequency as the power transmission frequency f0. In this example, the value indicated by “CB” is used.

  In addition, as for the resonance frequency of the coils 6a-6c of each apparatus, it is desirable to make it the same as the power transmission frequency f0 as an initial value at the time of charge start. By charging a single device by setting the resonance frequency and the power transmission frequency f0 to the same frequency, when charging a plurality of devices having the same efficiency as the charging power, charging a device having the maximum charging power among the plurality of devices. In this case, it is not necessary to perform processing for changing to the same frequency.

  The “efficiency information” stores information indicating the efficiency of each device in association with the information stored in the “device combination”. In this example, “EA1” to “EA7”, “EB1” to “EB6”, “EC1” to “EC6”,... Are stored as efficiency information. “EA1” to “EA7” are values indicating the efficiency corresponding to the identification information “A”. “EB1” to “EB6” are values indicating the efficiency corresponding to the identification information “B”. “EC1” to “EC6” are values indicating the efficiency corresponding to the identification information “C”.

  A method for determining variable information and efficiency information for devices other than the device with the maximum charging power will be described later.

  In step S7, for example, a case where a device A having a charging power of 50W, a device B having a charging power of 5W, and a device C having a charging power of 3W are charged at the same time will be described. The control unit 321 refers to the combination information 81 of FIG. 27 using the power reception information 72 of FIG. 26, and variable information “CA” “CB4” associated with “A”, “B”, and “C” of “device combination”. "" CC4 "is acquired. Thereafter, notification (transmission data) including variable information “CB4” notified to device B and identification information identifying device B, notification including variable information “CC4” notified to device C and identification information identifying device C (Transmission data). Then, the notifications generated via the communication unit 323 and the antenna 324 are transmitted to the devices B and C, respectively. Note that if the resonance frequency of the device A is not the same as the power transmission frequency, the notification including the variable information “CA” and the identification information for identifying the device A is also transmitted to the device A.

  In step S8, the control unit 321 sets the transmission power when the charging power of the plurality of devices is different or the efficiency is different. The transmission power when the charging power of the plurality of devices is different or the efficiency is different is determined by using the charging power of the received information and the efficiency corresponding to each device of the combination information stored in the storage unit 322. Ask for power. The transmitted power can be expressed by Equation 5.

Transmission power = (charging power 1 / efficiency 1) Equation 5
+ (Charging power 2 / efficiency 2)
+ (Charging power 3 / efficiency 3)
+ ...
For example, in the devices A, B, and C that are stored in the power receiving information, the charging power of the device A is PA and the efficiency is EA6, the charging power of the device B is PB, the efficiency is EB5, and the charging power of the device C Is a PC and the efficiency is EC4, the transmission power shown in Equation 6 is obtained.

Transmission power = (PA / EA6) Equation 6
+ (PB / EB5)
+ (PC / EC4)
Next, the control unit 321 sets the power supply unit 325 so that the power output from the power supply unit 325 becomes the power shown in Expression 6. However, the method for obtaining transmitted power is not limited to the above method. The number of devices is not limited to three.

  In step S9, the control unit 321 instructs the power supply unit 325 to start power transmission. Thereafter, the power supply unit 325 outputs the set power. If a new device is added on the way, the process proceeds to step S1. If there is a device that has been fully charged, the process proceeds to step S1.

  A method for determining variable information and efficiency information of devices other than the device with the maximum charging power will be described.

  As one of the determination methods, variable information and efficiency information may be determined using an actual system. Alternatively, an equivalent circuit of an actual system may be analyzed using a circuit simulator or the like to determine variable information and efficiency information.

  FIG. 28 is a diagram illustrating an embodiment of an equivalent circuit of a contactless charging system using magnetic field resonance and electric field resonance. An equivalent circuit 91 in FIG. 28 shows a non-contact charging system of magnetic field resonance using the four coils described in FIG. The equivalent circuit 92 shows a non-contact charging system using electric field resonance using four coils.

  The equivalent circuit 91 will be described. A circuit including the coil L1 and the resistor R1 includes the power supply coil 4 described with reference to FIG. A circuit including the coil L2, the capacitor C2, and the resistor R2 is a circuit including the power transmission resonance coil 5 described with reference to FIG. A circuit including the coil L3, the capacitor C3, and the resistor R3 is a circuit including the power receiving resonance coils 6a, 6b, and 6c described with reference to FIG. The circuit composed of the coil L4, the resistor R4, and the resistor ZL is a circuit having the power extraction coil 7a and the load ZLa, the power extraction coil 7b and the load ZLb, and the power extraction coil 7c and the load ZLc described in FIG. The resistor Rb is a resistor that exists between the power supply unit 3 and the power supply coil 4. Further, the equivalent circuit 91 shows a mutual inductance M12 between the coils L1 and L2, a mutual inductance M23 between the coils L2 and L3, and a mutual inductance M34 between the coils L3 and L4. Currents I1 to I4 are also shown.

  The equivalent circuit 92 will be described. The circuit composed of the coil L1 and the resistor R1 is a circuit having the power supply coil 4 described in FIG. A circuit including the coil L2, the capacitor C2, and the resistor R2 is a circuit having the power transmission resonance coil 5 described with reference to FIG. A circuit including the coil L3, the capacitor C3, and the resistor R3 is a circuit including the power receiving resonance coils 6a, 6b, and 6c described with reference to FIG. The circuit composed of the coil L4, the resistor R4, and the resistor ZL is a circuit having the power extraction coil 7a and the load ZLa, the power extraction coil 7b and the load ZLb, and the power extraction coil 7c and the load ZLc described in FIG. The resistor Rb is a resistor that exists between the power supply unit 3 and the power supply coil 4. In addition, the equivalent circuit 92 shows the mutual capacitance C23 of the capacitors C2 and C3 and the currents I1 to I4.

  In the magnetic field resonance or electric field resonance system, an equivalent circuit is created even when a circuit composed of the coil L1 and the resistor R1 is not used or when a circuit composed of the coil L4 and the resistor R4 is not used. Then, variable information and efficiency information may be determined for the created equivalent circuit using a circuit simulator or the like.

  FIG. 29 is a diagram showing an embodiment of an equivalent circuit of a magnetic resonance non-contact charging system. In this example, a case where two devices are charged simultaneously will be described. Even if there are a plurality of devices, the circuit configured by the coil L1 and the resistor R1 on the power transmission device 1 side and the circuit configured by the coil L2, the capacitor C2, and the resistor R2 are the same as the equivalent circuit 91.

  The LC resonance circuit of the power receiving unit 335 on the device A side in FIG. 29 includes a coil L3a, a capacitor C3a, and a resistor R3a, and the power extraction coil includes a coil L4a and a resistor R4a. The load on the device A side is indicated by ZLa. The LC resonance circuit of the power reception unit 335 on the device B side includes a coil L3b, a capacitor C3b, and a resistor R3b, and the power extraction coil includes a coil L4b and a resistor R4b. The load on the device B side is indicated by ZLb. In addition, although the example of two apparatuses is shown in this example, it is not limited to two.

  FIG. 30 shows the result of simulation using the equivalent circuit shown in FIG.

  FIG. 30 is a diagram illustrating an example of a simulation result. The vertical axis shows the power balance and efficiency, and the horizontal axis shows that the duty ratio of the control signals SW1 to SW4 for controlling the switch elements SW1 to SW4 of the bridge-type balanced circuit 160 of the power receiving unit 335 of the device B changes with respect to 50%. The amount of change (change amount: Δ%) is shown. A curve e1 is a simulation result when the capacitance of the capacitor C3 of the equivalent circuit 101 corresponding to the power receiving device of the device A is varied. A curve e2 is a simulation result when the capacitance of the capacitor C3 of the equivalent circuit 101 corresponding to the power receiving device of the device B is varied. For example, when the charging power of the device A is 50 W and the charging power of the device B is 5 W, the resonance frequency of the LC resonance circuit of the device A is not changed without changing the power transmission frequency, and the change amount of the device B is changed. As shown in FIG. 30, it can be seen that the charging power of the device A increases and the charging power of the device B decreases by decreasing the amount of change. It can also be seen that there is no significant change in the curve e3 indicating the overall efficiency.

  By performing the simulation as described above for each combination of devices, variable information and efficiency information of each device for each combination can be obtained.

  Here, as an example, a mode in which the charging power of the device A increases and the charging power of the device B decreases by decreasing the amount of change is shown, but on the contrary, the amount of change is increased. By doing so, the charging power of the device A may be increased, and the charging power of the device B may be decreased.

  Further, the Q value of the LC resonance circuit including the coil L3b, the capacitor C3b, and the resistor R3b of the power reception unit 335 of the device B can be indicated by using the current I3b shown in the LC resonance circuit. FIG. 31 is a diagram illustrating an example of the relationship between the power transmission frequency and the Q value of the power receiving unit. A graph 121 shows the relationship between the resonance frequency and the current I3 when the coil L3 of the equivalent circuit 91 is varied. A curve a1 represents a case where an alternating current is input to a circuit composed of the coil L3, the capacitor C3, and the resistor R3 with the transmission frequency f0 as the center. In this example, the capacitance value of the capacitor C3 of the circuit is set to a value at which the resonance frequency of the circuit and the power transmission frequency f0 are the same. A curve b indicates a change in the current I3 when a direct current is input to a circuit including the coil L3, the capacitor C3, and the resistor R3. The Q value at the power transmission frequency of the graph 121 can be represented by Ia1 / Ib. Ia1 is the value of the current I3 when the resonance frequency is the power transmission frequency f0. Ib indicates the current at the power transmission frequency f0.

  The graph 122 shows the relationship between the resonance frequency and the current I3 when the coil L3 of the equivalent circuit 91 is varied. A curve a2 shows a case where an alternating current is input to a circuit composed of the coil L3, the capacitor C3, and the resistor R3 with the transmission frequency f0 as the center. In this example, the capacitance value of the capacitor C3 of the circuit is set to a value at which the resonance frequency of the circuit and the power transmission frequency f0 are different. A curve b indicates a change in the current I3 when a direct current is input to a circuit including the coil L3, the capacitor C3, and the resistor R3. The Q value at the power transmission frequency of the graph 121 can be represented by Ia2 / Ib. Ia2 is the value of the current I3 when the resonance frequency is the power transmission frequency f0. Ib indicates the current at the power transmission frequency f0. That is, the Q value can be varied by varying the resonance frequency.

  The operation of the device 2 will be described with reference to FIG.

  FIG. 32 is a flowchart showing an embodiment of the operation of the device. In step S <b> 131, the control unit 331 transmits charging information to the power transmission device 1. For example, the control unit 331 acquires the identification number assigned to each device stored in the storage unit 332 and the charging power for each device, and generates charging information. Thereafter, the control unit 331 transfers the charging information to the communication unit 333 and transmits it to the power transmission device 1 via the antenna 334.

  In step S132, after transmitting the charging information to the power transmission device 1, the control unit 331 determines whether or not a notification transmitted from the power transmission device 1 has been received, and when the notification has been transmitted, the process proceeds to step S133 (Yes). If it is not transmitted, it waits (No). The notification is a notification (transmission data) transmitted by the power transmission device 1 in step S7 of FIG. The determination is made, for example, if the identification information included in the received notification is the same as the device that received the notification.

  In step S133, using the variable information included in the notification received by the control unit 331, the Q value is changed with reference to the Q value variable information. The Q value variable information is stored in the storage unit 332 and has information stored in “variable information” and “setting value”.

  FIG. 33 is a diagram illustrating an example of the data structure of the Q value variable information. In the Q value variable information 141, for example, a setting value for changing the amount of change of the power reception unit 335 of the device A is stored in the storage unit 332 in association with the variable information. In the Q value variable information 142, for example, a setting value that varies the amount of change of the power reception unit 335 of the device B is stored in the storage unit 332 in association with the variable information. In the Q value variable information 143, for example, a setting value for changing the amount of change of the power reception unit 335 of the device C is stored in the storage unit 332 in association with the variable information. In “variable information”, a value for setting a change amount of the power receiving unit 335 of each device is stored. In this example, values “CA”, “CA1”, “CA2”,..., “CA8”,. As the “variable information” of the device B, values “CB”, “CB1”, “CB2”,..., “CB8”,. As the “variable information” of the device C, values “CC”, “CC1”, “CC2”,..., “CC8”,. Control data representing the duty ratio is stored in the “set value”. The ratio of opening and closing the switches SW1 to SW4 is determined by the duty ratio. In this example, “dataA0”, “dataA1”, “dataA2”,... “DataA8”,. “DataB0”, “dataB1”, “dataB2”,... “DataB8”,. “DataC0”, “dataC1”, “dataC2”,..., “DataC8”,.

  When the change amount represents a phase difference, information representing a phase is stored as a set value. This is the same for both electric field resonance and magnetic field resonance.

  In step S134, when the control unit 331 detects that the change of the Q value is completed, the control unit 331 shifts to a charging start state. In addition, you may notify the power transmission apparatus 1 that it is a charge start state.

  In step S135, the control unit 331 detects that charging is completed. When the completion of charging is detected, the control unit 331 ends charging and ends the process (Yes), and continues charging (No) when the completion of charging is not detected. For example, the charging is completed when the output voltage of the battery is measured and the charging is completed if it is equal to or greater than a threshold value. Note that the power transmission device 1 may be notified that the charging has been completed, and the power transmission device 1 may end the charging.

  Conventionally, since it is configured to receive constant power on the charging stand of the power transmission device, the charging power received by each device has the same value, so when charging devices with different charging power, excessive or insufficient power Problem occurs. However, according to the present embodiment, even when a plurality of devices having different charging powers are fed simultaneously, appropriate power can be supplied to devices having different charging powers.

  Also, as shown in FIG. 30, since it is possible to adjust the power balance, it is possible to charge a plurality of devices having different charging powers at the same time. Moreover, since the power transmission efficiency (curve e3) at that time can be maintained at a high level, the loss during power transmission can be minimized.

  Further, in the device A (50 W) and the device B (5 W) on the power receiving side, when the ratio of the charging power of the device B is set to a condition that A: B = 10: 1 in advance, the device B is singly charged. Then, the problem that power transmission efficiency will become extremely low is assumed. Furthermore, a problem that cannot be handled by a combination such as A: B = 5: 1 is assumed. However, according to the present embodiment, the resonance frequency or the Q value can be adjusted according to the power balance to be combined, so that the above problem can be solved.

  Also, even when there are a plurality of the same devices, the required charging power may differ depending on the charging status of the battery. Also, when there is a difference in power distribution on the charging stand, the required charging power may be different. For example, when the power received at the center of the charging stand is large, it is assumed that a 5 W device cannot be placed at the center and a 50 W device cannot be placed at the end of the charging stand. However, by using the present embodiment, the above problem can be solved by adjusting the resonance frequency or the Q value according to the power balance in consideration of the charging state of the battery and the power distribution of the charging stand in advance. Is also possible.

  In the second embodiment, the resonance frequency can be varied using the bridge-type balanced circuit 160. The bridge-type balanced circuit 160 is a simple circuit that can be realized by a bridge circuit including switch elements SW1 to SW4, a resistor, and a capacitor.

  For this reason, according to the second embodiment, the efficiency of power transmission can be improved by changing the resonance frequency with a simple configuration.

  In addition, although the power transmission apparatus 1 demonstrated the form containing the power supply part 3, the power supply coil 4, and the power transmission resonance coil 5 above, the power transmission apparatus 1 does not include the power supply coil 4, but from the power supply part 3. You may make it supply electric power to the power transmission resonance coil 5 directly.

<Embodiment 3>
FIG. 34 is a diagram illustrating an example of a system including the power transmission device and the power reception device according to the third embodiment. FIG. 35 is a diagram illustrating an example of a system including the power transmission device and the power reception device according to the third embodiment. In the second embodiment, the power transmission device 1 in FIG. 34 is the main body, and variable information is transmitted to each device. That is, the control unit 321 in FIG. 34 obtains variable information and transmits the variable information to each device.

  In the third embodiment, one of the devices is the main body (first device) and controls the power transmission apparatus and the other device (second device). In the example of FIG. 35, the device 2a (first device) is the main body, and variable information is transmitted to the device 2b (second device) that is a device other than the device 2a. Further, the device 2a transmits information necessary for supplying the power transmission apparatus 1 with the transmission power to be transmitted to the device 2a and the device 2b. Thereafter, the power transmission device 1 transmits power to the devices 2a and 2b.

  The control unit 331a in FIG. 35 controls each unit of the device 2a. When the device 2a is the main device shown in FIG. 35, the control unit 331a obtains variable information of the devices 2a and 2b and transmits the variable information to the device 2b.

  Further, the control unit 331a acquires charging information stored in the storage unit 332a or the like having identification information for identifying the device 2a and information indicating charging power associated with the device 2a. Further, the control unit 331a acquires the charging information transmitted from the device 2b via the communication unit 333a.

  In addition, the control unit 331a obtains transmission power using charging power and efficiency corresponding to the devices 2a and 2b, and transmits information indicating the transmission power to the power transmission device 1. Note that charging power and efficiency corresponding to the devices 2a and 2b may be transmitted from the device 2a, and the power transmission device 1 may obtain the transmitted power. For example, the transmission power may be obtained by using each of the acquired identification information and referring to each efficiency associated with the identification information and using the charging power and efficiency corresponding to each of the acquired devices. It is done.

  Further, the control unit 331a generates variable information that varies the resonance frequency or the Q value of the resonance circuit included in each of the power reception unit 335a of the device 2a and the power reception unit 335b of the device 2b. For example, the device 2a refers to the combination information having variable information of each of the devices associated with each combination of one or more devices and each of the one or more device combinations stored in the storage unit 332a. Using the identified information, variable information associated with each device is selected.

  When the resonance frequency or Q value of the device 2a is varied, the resonance frequency or Q value of the resonance circuit is varied using variable information. When changing the resonance frequency or Q value of the device 2b, variable information corresponding to the device 2b is transmitted from the device 2a. The device 2b that has received the variable information varies the resonance frequency or Q value of the resonance circuit using the variable information.

  Note that when the device 2a is a device with the maximum charging power, the resonance frequency of the resonance circuit of the power reception unit 335a is changed to the power transmission frequency. When the device 2a is a device other than the device with the largest charge power, the transmission power transmitted from the power transmission device 1 is the resonance frequency of the resonance circuit of the power receiving unit 335a and the charge power corresponding to the device other than the device with the largest charge power. To a frequency that can be supplied.

  The control unit 331b in FIG. 35 controls each unit of the device 2b. The control unit 331b generates charging information including identification information for identifying the device and information indicating charging power associated with the device. Then, the charging information is transmitted from the communication unit 333b to the communication unit 333a. In addition, the control unit 331b acquires variable information transmitted from the device 2a via the communication unit 333b.

  When the device 2b is a device with the maximum charging power, the resonance frequency of the resonance circuit of the power reception unit 335b is changed to the power transmission frequency. When the device 2b is a device other than the device with the maximum charging power, the transmission power transmitted from the power transmission device 1 is the resonance frequency of the resonance circuit of the power receiving unit 335b and the charging power corresponding to the device other than the device with the largest charging power. To a frequency that can be supplied.

  The control unit 321 in FIG. 35 controls each unit of the power transmission device 1. Moreover, the control part 321 of FIG. 35 acquires the information which shows transmitted power from the apparatus 2a. Alternatively, the charging power and efficiency corresponding to the devices 2a and 2b are received from the device 2a, and the transmitted power is obtained. Thereafter, the control unit 321 performs control to transmit power.

  The operation of the main device (first device having a power receiving device) will be described.

  36 and 37 are flowcharts showing an embodiment of the operation of the main device. In step S1701, the charging information stored in the first device and the charging information transmitted from the second device using wireless communication received by the first device are the first. Acquired by the control unit of the device. For example, when the first device is the device 2a and the second device is the device 2b, the communication unit 333a transfers the charging information of the device 2b included in the received signal to the control unit 331a.

  Subsequently, in step S1701, the control unit 331a stores the charging information received from the device 2b in the power reception information of the storage unit 332a. The power reception information includes identification information for identifying the device and information indicating the charging power of each device. See FIG. 26 for charging information and power receiving information.

  In step S1701, after the control unit 331a receives the signal including the charging information from the device and confirms that the signal including the charging information is not transmitted from the device for a certain period, the process proceeds to step S1702. That is, the device to be charged is determined. For example, when the devices 2a and 2b are arranged in the power transmission device 1, after acquiring the charging information 71a and 71b, if the charging information is not newly received even after a certain period of time, the process proceeds to step S1702. Further, when a new signal including charging information is received from the device 2c within a certain period, the apparatus further stands by for a certain period, and when no new charging information is received after a certain period of time, the process proceeds to step S1702. In addition, determination of the apparatus to charge is not limited to the said method, You may use another method.

  In step S <b> 1702, the control unit of the main device determines whether or not the main device is the only device arranged in the power transmission device 1 with reference to the power reception information. If there is only the subject (Yes), the process proceeds to step S1703, and if the device is other than the subject (No), the process proceeds to step S1704. For example, when referring to the power reception information 72 of FIG. 26, it is detected that the three devices 2a, 2b, and 2c are arranged in the power transmission device 1, and there are devices other than the main body, and the process proceeds to step S1704.

  In step S1703, the control unit of the main device sets transmission power. The transmission power in the case of only the subject is obtained using the charging power of the power reception information and the efficiency of the efficiency information stored in the storage unit 332a. The transmitted power can be expressed by Equation 3.

  For example, the control unit 331a refers to the power reception information 72, acquires “50” indicating 50 W that is charging power corresponding to the identification information “A”, and refers to the efficiency information 73 to correspond to the identification information “A”. "0.8" indicating 80%, which is the efficiency to be acquired, is acquired. Thereafter, charging power / efficiency is calculated to obtain transmission power 62.5W.

  In step S1704, the control unit of the main device refers to the power reception information to determine whether or not the charging power of the plurality of devices is the same and the efficiency is the same, and in the case of being the same (Yes), the process proceeds to step S1705. If there is a difference (No), the process moves to step S1706 in FIG.

  In step S1705, the control unit of the main device sets the transmission power when the charging power of the plurality of devices is the same and the efficiency is the same. The transmission power when the charging power of a plurality of devices is the same is determined by using the charging power of the power receiving information, the number of devices to be charged (number), and the efficiency of the efficiency information stored in the storage unit 332a. Ask for. The transmitted power can be expressed by Equation 4. For example, when the number of devices to be charged stored in the power reception information is 3, the charging power corresponding to each device is 5 W, and the efficiency is 0.8 (80%), the equation 4 is used. Thus, the transmission power of 18.75 W is obtained.

  In step S1706 of FIG. 37, the control unit of the main device selects a device other than the device with the maximum charging power with reference to the power reception information. For example, the control unit 331a refers to “charging information” in the power reception information 72 and selects a device other than the device with the maximum charging power. In this example, since the device with the maximum charging power is the device with the identification information “A”, the devices with the identification information “B” and “C” are selected.

  In step S1707 of FIG. 37, a notification for changing the resonance frequency or Q value of the power receiving unit of each of the selected devices other than the main body is transmitted to each of the selected devices by the control unit of the main power receiving apparatus. In step S1707, the control unit 331a refers to the combination information using the received identification information, and acquires variable information corresponding to the combination of devices to be charged simultaneously.

  In step S1707, for example, a case where the main device A having a charging power of 50 W, a device B having a charging power of 5 W, and a device C having a charging power of 3 W are charged at the same time will be described. The control unit 331a refers to the combination information 81 in FIG. 27 by using the power reception information 72 in FIG. 26, and variable information “CA” “CB4” associated with “A”, “B”, and “C” of “device combination”. "" CC4 "is acquired. Thereafter, notification (transmission data) including variable information “CB4” notified to device B and identification information identifying device B, notification including variable information “CC4” notified to device C and identification information identifying device C (Transmission data). Then, the notifications generated via the communication unit 333a and the antenna 334a are transmitted to the devices B and C, respectively.

  When the control unit of the main device in step S1708 of FIG. 37 needs to change the resonance frequency or the Q value of the main device, the Q value stored in the storage unit 332a using the variable information. The resonance frequency or Q value is changed with reference to the variable information.

  In step S1709 in FIG. 37, the control unit of the main device sets transmission power when charging power of a plurality of devices is different or efficiency is different. The transmission power when the charging power of the plurality of devices is different or the efficiency is different is determined by using the charging power of the received information and the efficiency corresponding to each of the devices of the combination information stored in the storage unit 332a. Ask for power. The transmitted power can be expressed by Equation 5.

  In step S1710, the control unit of the main device transmits transmission power information to the power transmission device via the communication unit. The control unit 331a transmits the transmission power information to the power transmission device 1 via the communication unit 333a.

  In step S1711, the control unit of the main device performs a charging process. For example, when the control unit 331a detects that the change of the Q value has been completed, the state is shifted to the charging start state. In addition, you may notify the power transmission apparatus 1 that it is a charge start state.

  In step S1712, the control unit of the main device detects that the charging is completed. When the control unit 331a detects completion of charging, the control unit 331a ends the charging process (Yes), and continues charging when no completion of charging is detected (No). For example, the charging is completed when the output voltage of the battery is measured and the charging is completed if it is equal to or greater than a threshold value. Note that the power transmission device 1 may be notified that the charging has been completed, and the power transmission device 1 may end the charging.

  The operation of a device other than the main device will be described.

  FIG. 38 is a flowchart showing an embodiment of the operation of devices other than the subject. In the case of Embodiment 3, in step S1901, the control unit of a device other than the main device transmits charging information to the main device. For example, the control unit 331b acquires the identification number assigned to each device stored in the storage unit 332b and the charging power for each device, and generates charging information. Thereafter, the control unit 331b transfers the charging information to the communication unit 333b and transmits it to the device 2a via the antenna 334b.

  In step S1902, after the charging information is transmitted to the device 2a, the control unit 331b determines whether or not a notification transmitted from the device 2a is received. If the notification is transmitted (Yes), the process proceeds to step S1903. If it has not been transmitted (No), it waits. The determination is made, for example, if the identification information included in the received notification is the same as the device that received the notification.

  In step S1903, using the variable information included in the notification received by the control unit 331b, the Q value is changed with reference to the Q value variable information stored in the storage unit 332b.

  In step S1904, when the control unit 331b detects that the Q value has been changed, a charging process is performed. In addition, you may notify the power transmission apparatus 1 that it is a charge process state.

  In step S1905, the control unit 331b detects that charging has been completed. When the completion of charging is detected, the control unit 331b ends the charging and ends the process (Yes), and continues charging when the completion of charging is not detected (No). For example, the charging is completed when the output voltage of the battery is measured and the charging is completed if it is equal to or greater than a threshold value. In addition, you may notify the power transmission apparatus 1 via the apparatus 2a that charging was completed, and you may complete | finish charging.

  The operation of the power transmission device according to the third embodiment will be described.

  FIG. 39 is a flowchart illustrating an example of operation of the power transmission device according to the third embodiment. In step S2001, the control unit 321 of the power transmission apparatus in FIG. 35 receives transmission power information from the main device 2a.

  In step S2002, the control unit 321 performs setting so that the power indicated by the transmitted power information can be transmitted from the power supply unit 325 and the power transmission unit 326.

  In step S2003, when it is detected that power transmission preparation is completed, the control unit 321 performs a charging process. In addition, you may notify the charging device 2a that it is a charge processing state.

  In step S2004, the control unit 321 detects that charging has been completed. When detecting the completion of charging, the control unit 321 ends the charging and ends the process (Yes), and continues the charging when the completion of the charging is not detected (No).

  According to the third embodiment, even when power is supplied to a plurality of devices having different charging powers simultaneously, appropriate power can be supplied to devices having different charging powers.

  In addition, since the power balance can be adjusted, it is possible to charge a plurality of devices having different charging powers at the same time. In addition, loss during power transmission can be minimized.

  Further, according to the third embodiment, the resonance frequency or the Q value can be adjusted according to the power balance to be combined.

  Further, by using the third embodiment, it is possible to adjust the resonance frequency or the Q value in accordance with the power balance in consideration of the charging state of the battery and the power distribution of the charging stand in advance.

  In addition, although the case where there is one main device has been described, a plurality of devices may perform the above-described processing separately.

<Embodiment 4>
FIG. 40 is a diagram illustrating an example of a system including the power transmission device, the power reception device, and the external device according to the fourth embodiment. In the fourth embodiment, the external device 2100 performs control for charging the devices 2a and 2b from the power transmission device 1 shown in FIG.

  The external device 2100 is a device such as a computer and can communicate with the power transmission device 1 and the devices 2a and 2b. The external device 2100 may be a server or a cloud, for example.

  The control unit 2101 may be a central processing unit (CPU), a multi-core CPU, or a programmable device (such as a field programmable gate array (FPGA) or a programmable logic device (PLD)).

  The storage unit 2102 stores power reception information, efficiency information, combination information, and the like, which will be described later. As the storage unit 2102, for example, a memory such as a read only memory (ROM), a flash-ROM, a random access memory (RAM), or a FeRAM, a hard disk, or the like can be considered. Data such as parameter values and variable values may be recorded in the storage unit 2102 or may be used as a work area at the time of execution. A program is stored in the storage unit 2102 (nonvolatile memory such as ROM, Flash-ROM, or FeRAM), and the processing is executed while being read by the control unit at the time of execution.

  The communication unit 2103 is an interface that is connected to the antenna 2104 and performs communication such as wireless communication with the communication units of the power transmission device 1 and the devices 2a and 2b. For example, an interface for wireless connection such as a wireless local area network (LAN) or Bluetooth can be considered.

  The external device 2100 may include a recording medium reading device and an input / output interface. The recording medium reading device controls reading / writing of data with respect to the recording medium according to the control of the control unit 2101. Then, the data written under the control of the recording medium reader is recorded on the recording medium, or the data recorded on the recording medium is read. The detachable recording medium includes a magnetic recording device, an optical disk, a magneto-optical recording medium, a semiconductor memory, and the like as a computer-readable non-transitory recording medium. The magnetic recording device includes a hard disk device (HDD). Optical discs include Digital Versatile Disc (DVD), DVD-RAM, Compact Disc Read Only Memory (CD-ROM), and CD-R (Recordable) / RW (ReWritable). Magneto-optical recording media include magneto-optical disks (MO). Note that the storage unit 2102 is also included in a non-transitory recording medium. Note that the recording medium and the recording medium reading device are not essential.

  An input / output unit such as a computer is connected to the input / output interface, receives information input by the user, and transmits the information to the control unit 2101 or the storage unit 2102 via the bus. As the input device of the input / output unit, for example, a keyboard, a pointing device (such as a mouse), a touch panel, and the like can be considered. In addition, the display which is an output part of an input / output part can consider a liquid crystal display etc., for example. The output unit may be an output device such as a Cathode Ray Tube (CRT) display or a printer.

  Further, by using a computer having the hardware configuration described above, various processing functions in the fourth embodiment to be described later may be realized. In this case, a program describing the processing contents of the functions that the computer should have is provided. By executing the program on a computer, the above processing functions are realized on the computer. The program describing the processing contents can be recorded on a computer-readable recording medium.

  When distributing the program, for example, a recording medium such as a DVD or a CD-ROM in which the program is recorded is sold. It is also possible to record the program in a storage device of the server computer and transfer the program from the server computer to another computer via a network.

  The computer that executes the program records, for example, the program recorded on the recording medium or the program transferred from the server computer in its own storage unit 2102. Then, the computer reads the program from its own storage unit 2102 and executes processing according to the program.

  The control unit 2101 controls each unit of the external device 2100. In addition, the control unit 2101 acquires identification information for identifying the devices 2a and 2b and information indicating the charging power associated with each of the devices 2a and 2b from each of the devices 2a and 2b. The control unit 2101 uses each of the acquired identification information to change the resonance frequency or Q value of the combination of the devices 2a and 2b and the resonance circuit of the power receiving unit of each of the devices 2a and 2b associated with the combination. Generate information. The control unit 2101 refers to the combination information having variable information of each of the devices 2a and 2b associated with each combination of the one or more devices 2a and 2b and each of the combinations of the one or more devices 2a and 2b. Each piece of identification information is used to select variable information associated with each of the devices 2a and 2b. The control unit 2101 transmits variable information to each of the devices 2a and 2b.

  The control unit 2101 obtains transmission power using the charging power and efficiency corresponding to the devices 2a and 2b, and transmits information indicating the transmission power to the power transmission device 1. Note that the charging power and efficiency corresponding to the devices 2a and 2b may be transmitted from the external device 2100, and the power transmission device 1 may obtain the transmission power. For example, each of the acquired identification information is used to refer to the efficiency associated with the identification information, and the transmission power is acquired for the power and efficiency corresponding to each of the devices, and the acquired charge power and efficiency are used. The transmission power can be calculated. However, the method for obtaining transmitted power is not limited to the above method.

  The operation of the external device will be described.

  41 and 42 are flowcharts showing an embodiment of the operation of the external device. In step S2201, the control unit 2101 of the external device 2100 acquires charging information transmitted from the devices 2a and 2b using wireless communication or the like. The communication unit 2103 transfers the charging information of the devices 2 a and 2 b included in the received signal to the control unit 2101.

  Subsequently, in step S2201, the control unit 2101 stores the charging information received from the devices 2a and 2b in the power reception information of the storage unit 2102. The power reception information includes identification information for identifying the device and information indicating the charging power of each device. See FIG. 26 for charging information and power receiving information.

  In step S2201, after receiving a signal including charging information from the device, the control unit 2101 proceeds to step S2202 when confirming that a signal including charging information is not transmitted from the device for a certain period. That is, the device to be charged is determined. For example, when the devices 2a and 2b are arranged in the power transmission device 1, after acquiring the charging information 71a and 71b, if the charging information is not newly received even after a certain period of time, the process proceeds to step S2202. In addition, when a signal including charging information is newly received from the device 2c within a certain period, the apparatus further waits for a certain period, and proceeds to step S2202 when no new charging information is received after a certain period. In addition, determination of the apparatus to charge is not limited to the said method, You may use another method.

  In step S2202, the control unit 2101 refers to the power reception information to determine whether the number of devices arranged in the power transmission device 1 is singular. If the number is singular (Yes), the process proceeds to step S2203. In the case (No), the process proceeds to step S2204. For example, when referring to the power reception information 72 of FIG. 26, it is detected that the three devices 2a, 2b, and 2c are arranged in the power transmission device 1, and the process proceeds to step S2204.

  In step S2203, the control unit 2101 sets transmission power. The transmission power is obtained by using the charging power of the power reception information and the efficiency information stored in the storage unit 2102. The transmitted power can be expressed by Equation 3.

  For example, the control unit 2101 refers to the power reception information 72 to acquire “50” indicating 50 W that is the charging power corresponding to the identification information “A”, and refers to the efficiency information 73 to correspond to the identification information “A”. "0.8" indicating 80%, which is the efficiency to be acquired, is acquired. Thereafter, charging power / efficiency is calculated to obtain transmission power 62.5W.

  In step S2204, the control unit 2101 refers to the power reception information to determine whether or not the charging powers of the plurality of devices are the same and the efficiency is the same. If they are the same (Yes), the process proceeds to step S2205 and is different. In the case (No), the process proceeds to step S2206 in FIG.

  In step S2205, the control unit 2101 sets transmission power when the charging power of the plurality of devices is the same and the efficiency is the same. The transmission power when the charging power of a plurality of devices is the same is calculated by using the charging power of the power reception information, the number of devices to be charged (number), and the efficiency of the efficiency information stored in the storage unit 2102. Ask for. The transmitted power can be expressed by Equation 4.

  For example, when the number of devices to be charged stored in the power reception information is 3, the charging power corresponding to each device is 5 W, and the efficiency is 0.8 (80%), the equation 4 is used. The transmission power of 18.75 W is obtained.

  In step S2206 of FIG. 42, the control unit 2101 selects a device other than the device with the maximum charging power with reference to the power reception information. For example, the control unit 2101 refers to “charging information” in the power reception information 72 and selects a device other than the device with the maximum charging power. In this example, since the device with the maximum charging power is the device with the identification information “A”, the devices with the identification information “B” and “C” are selected.

  In step S2207 of FIG. 42, the control unit 2101 transmits a notification for changing the resonance frequency or the Q value of each power receiving unit of each selected device to each selected device. In step S2207, the control unit 2101 refers to the combination information using the received identification information, and acquires variable information corresponding to the combination of devices to be charged simultaneously.

  In step S2207, for example, a case where a device A with a charging power of 50 W, a device B with a charging power of 5 W, and a device C with a charging power of 3 W are charged at the same time will be described. The control unit 331a refers to the combination information 81 in FIG. 27 by using the power reception information 72 in FIG. 26, and variable information “CA” “CB4” associated with “A”, “B”, and “C” of “device combination”. "" CC4 "is acquired. Thereafter, the variable information “CA” notified to the device A and the notification including the identification information for identifying the device A, the variable information “CB4” to be notified to the device B, the notification including the identification information for identifying the device B, and the device C The variable information “CC4” to be notified to and the notification including the identification information for identifying the device C are generated. Then, each notification generated via the communication unit 2103 and the antenna 2104 is transmitted to the devices A, B, and C.

  In step S2208 of FIG. 42, the control unit 2101 sets transmission power when charging power of a plurality of devices is different or efficiency is different. The transmission power when the charging power of the plurality of devices is different or the efficiency is different is determined by using each of the charging power of the received information and the efficiency corresponding to each of the devices of the combination information stored in the storage unit 2102. Ask for power. The transmitted power can be expressed by Equation 5.

  In step S <b> 2209, the control unit 2101 transmits transmission power information to the power transmission device 1 via the communication unit 2103. The control unit 2101 transmits transmission power information to the power transmission device 1 via the communication unit 2103.

  In step S2210, the control unit 2101 performs a charging process. For example, when the control unit 2101 detects that the change of the Q value has been completed, it shifts to a charging start state. In addition, you may notify the power transmission apparatus 1 that it is a charge start state.

  In step S2211, the control unit 2101 detects that charging has been completed. When the control unit 2101 detects the completion of charging, the control unit 2101 ends the charging process (Yes), and continues charging when the completion of charging is not detected (No). For example, the charging is completed when the output voltage of the battery is measured and the charging is completed if it is equal to or greater than a threshold value. Note that the power transmission device 1 may be notified that the charging has been completed, and the power transmission device 1 may end the charging.

  The operation of the device in the fourth embodiment will be described.

  FIG. 43 is a flowchart showing an example of the operation of the device in the fourth embodiment. In the case of the fourth embodiment, in step S2401, the control unit transmits charging information to the external device. For example, the control unit 331a acquires the identification number assigned to each device stored in the storage unit 332a and the charging power for each device, and generates charging information. Thereafter, the control unit 331a transfers the charging information to the communication unit 333a and transmits it to the external device 2100 via the antenna 334a.

  In step S2402, after transmitting the charging information to the external device 2100, the control unit of the device determines whether or not a notification transmitted from the external device 2100 has been received. If the notification has been transmitted (Yes), step S2403 is performed. If it is not transmitted (No), it waits. The determination is made, for example, if the identification information included in the received notification is the same as the device that received the notification.

  In step S2403, using the variable information included in the notification received by the control unit of the device, the Q value is changed with reference to the Q value variable information stored in the storage unit of the device.

  In step S2404, when the control unit of the device detects that the Q value has been changed, a charging process is performed. In addition, you may notify the power transmission apparatus 1 that it is a charge process state.

  In step S2405, the control unit of the device detects that charging has been completed. When the controller detects the completion of charging, the controller ends charging and ends the process (Yes), and continues charging when no completion of charging is detected (No). For example, the charging is completed when the output voltage of the battery is measured and the charging is completed if it is equal to or greater than a threshold value. In addition, the power transmission device 1 may be notified via the external device 2100 that the charging has been completed, and the charging may be terminated.

  The operation of the power transmission device according to the fourth embodiment will be described.

  FIG. 44 is a flowchart illustrating an example of operation of the power transmission device according to the fourth embodiment. In step S2501, the control unit 321 of the power transmission device 1 in FIG. 40 receives transmission power information from the external device 2100.

  In step S <b> 2502, the control unit 321 performs settings so that the power indicated by the transmitted power information can be transmitted from the power supply unit 325 and the power transmission unit 326.

  In step S2503, when it is detected that preparation for power transmission is completed, the control unit 321 performs a charging process. In addition, you may notify the apparatus 2a that it is a charge process state.

  In step S2504, the control unit 321 detects that charging has been completed. When detecting the completion of charging, the control unit 321 ends the charging and ends the process (Yes), and continues the charging when the completion of the charging is not detected (No).

  According to the fourth embodiment, it is possible to supply appropriate power to devices having different charging powers even when power is simultaneously supplied to devices having different charging powers.

  In addition, since the power balance can be adjusted, it is possible to charge a plurality of devices having different charging powers at the same time. In addition, loss during power transmission can be minimized.

  Further, according to the fourth embodiment, the resonance frequency or the Q value can be adjusted according to the power balance to be combined.

  In addition, by using the fourth embodiment, it is possible to adjust the resonance frequency or the Q value according to the power balance in consideration of the charging state of the battery and the power distribution of the charging stand in advance.

<Embodiment 5>
45 and 46 are diagrams illustrating the positional relationship between the power transmission resonance coil and the power reception resonance coil according to the fifth embodiment. The power receiving resonance coils 6a and 6b shown in FIGS. 45 and 46 are the same coil, and the efficiency of each device including the power receiving resonance coils 6a and 6b is also the same. The power receiving resonance coil 6c shown in FIG. 46 is different from the power receiving resonance coils 6a and 6b, and the efficiency of each device including the power receiving resonance coil 6c is also different from that of the power receiving resonance coils 6a and 6b.

  In FIG. 45A, the power receiving resonance coils 6 a and 6 b are at the same distance and the posture is the same with respect to the power transmission resonance coil 5. 45B of FIG. 45, the power receiving resonance coils 6a and 6b have the same posture with respect to the power transmission resonance coil 5, but the distances between the power reception resonance coils 6a and 6b are different. 45C of FIG. 45 differs from the power transmission resonance coil 5 in the distance and posture of the power reception resonance coils 6a and 6b. If the distances or postures of the power receiving resonance coils 6a and 6b with respect to the power transmission resonance coil 5 are different, the efficiency also changes. Therefore, the resonance frequency or the Q value must be adjusted in consideration of the change in efficiency, and the transmission power must also be obtained.

  46A, the power receiving resonance coils 6a and 6c are at the same distance from the power transmission resonance coil 5, and the posture is also the same. 46B, the power receiving resonance coil 6a is closer to the power transmission resonance coil 5 than the power reception resonance coil 6c, and the postures of the power reception resonance coils 6a and 6c are the same. 46C, the power receiving resonance coil 6c is closer to the power transmission resonance coil 5 than the power reception resonance coil 6a, and the postures of the power reception resonance coils 6a and 6c are the same. If the distance or posture of the power receiving resonance coil 6a, 6c with respect to the power transmission resonance coil 5 is different, the efficiency also changes. Therefore, even in the case shown in FIG. 46, the resonance frequency or Q value of the device is adjusted in consideration of the change in efficiency. And the transmission power must be determined.

  Therefore, in the fifth embodiment, even when the efficiency due to the positional relationship between the power transmission device and the device changes, it is possible to supply appropriate power to the device by taking the efficiency into consideration.

  FIG. 47 is a diagram illustrating an example of a main control unit according to the fifth embodiment. FIG. 48 is a diagram illustrating an example of a data structure of state-efficiency information according to the fifth embodiment. FIG. 49 is a diagram illustrating an example of the data structure of the combination information according to the fifth embodiment.

  The acquisition unit 2801 acquires information used to obtain the positional relationship between the power transmission device and the device. The acquisition unit may be an imaging device, for example. As information used for obtaining the positional relationship, image information captured by the imaging device, information indicating the positional relationship measured by the sensor, and the like can be considered. However, the information used for obtaining the positional relationship is not limited to image data, and may be any information as long as the positional relationship is known.

  The detection unit 2802, the efficiency calculation unit 2803, the selection unit 2804, the variable information calculation unit 2805, and the transmission power calculation unit 2806 illustrated in FIG. 47 are provided in the control unit of the main device. That is, it is provided in any one of the power transmission device 1, the device, and the external device.

  The detection unit 2802 obtains information used for obtaining the positional relationship, and obtains state information indicating the positional relationship between the power transmission apparatus and the device. As the state information, for example, information indicating the position and posture of the device in the three-dimensional space can be considered. The position is taken by photographing the device with the specific marker with the imaging device, analyzing the captured image information using image processing, etc., recognizing the device, and the visual field position from the position where the recognized device was photographed And the position in the three-dimensional space are estimated from the depth (distance). The posture is estimated using the recognized device marker and the outline image.

  The efficiency calculation unit 2803 obtains efficiency information indicating the efficiency from the obtained state information. For example, it may be obtained using the state-efficiency information 2901 in FIG. The state-efficiency information 2901 has information stored in “ID”, “state information”, and “efficiency information”. In “ID”, information for identifying the device is stored. In this example, “A”, “B”,... Are stored as identification information.

  In the “status information”, for example, position information indicating the position of the device in the three-dimensional space and attitude information indicating the attitude are stored. In this example, position information “LA1”, “LA2”... “LB1”, “LB2”,. In the posture information, posture information “RA1” “RA2”... “RB1” “RB2”... Is associated with information stored in “ID” and “position information”.

  The “efficiency information” stores the efficiency obtained from the positional relationship between the power transmission device and the device. In this example, “EA11”, “EA12”, “EA21”, “EA22”, “EB11”, “EB12”, “EB21”, “EB22”,. "Related to the information stored in" status information ". The stored efficiency information can be obtained by experiments or simulations.

  The selection unit 2804 obtains the second charging information using the first charging information and the efficiency information acquired from each device. The first charging information is, for example, charging information for each device stored in the power reception information 72 in FIG. The efficiency information is efficiency information based on the positional relationship obtained by the efficiency calculation unit 2803. The second charging information is, for example, when the first charging power acquired from the device (the power requested by the device) is 5 W and the efficiency information (single efficiency) based on the positional relationship is 10%. Can be expressed as: first charging power / single unit efficiency = 50 W (= 5 / 0.1).

  In addition, when the first charging power is 20 W and the single efficiency is 80%, the second charging information can be expressed by the first charging power / single efficiency = 25 W (= 20 / 0.8).

  Subsequently, the selection unit 2804 selects a device other than the device corresponding to the maximum second charging information from the obtained second charging information.

  The variable information calculation unit 2805 obtains variable information from the combination of the efficiency information of the devices selected by the selection unit 2804. For example, it may be obtained using the combination information 3001 in FIG. The combination information 3001 has information stored in “combination” and “variable information”.

  The “combination” stores a combination of efficiency for each device. In this example, combinations of efficiency of different devices corresponding to the identification information “A”, “B”,... Are stored. A combination of device efficiency will be described. When the efficiency of one device A is “EA11”, only “EA11” is stored in the “combination”. When the two devices A1 and A2 have the same efficiency “EA11”, the “combination” stores the efficiency “EA11” and “EA11” of the devices A1 and A2. The same applies to the case where two or more identical devices have the same efficiency. When the efficiency of the device A1 is “EA11” and the efficiency of the device B1 is “EB11”, the “combination” stores the efficiency “EA11” and “EB11” of the two devices A1 and B1. The same is true for the other combinations.

  “Variable information” stores information for varying the resonance frequency or Q value of each device in association with the information stored in “combination”. In this example, variable information “CA11” “CA12” of the devices A1, A2 and variable information “CB11”, “CB12”,... Of the devices B1, B2 are stored. The values indicated by “CA11”, “CA12”,... Are values used to set the amount of change of the power reception unit 335 of the device corresponding to the identification information “A1”, “A2”,. “CB11”, “CB12”,... Are values used to set a change amount of the power receiving unit 335 of the device corresponding to the identification information “B1” “B2”.

  In addition, the variable information calculation unit 2805 transmits a notification including variable information for changing the resonance frequency or Q value of the power reception unit 335 of each selected device to each selected device.

  It is assumed that the resonance frequency or Q value of the power reception unit 335 of the device is set to an optimum value for charging the charging power of the first charging information before the start of charging. The optimum value is, for example, a value at which charging from the power transmission device 1 to the device is most efficient.

  The transmitted power calculation unit 2806 obtains the transmitted power using the second charging power of all devices transmitted from the power transmission device 1.

  The operation of the control unit that is the subject of the fifth embodiment will be described.

  FIG. 50 is a diagram illustrating an example of the operation of the main control unit in the fifth embodiment. In step S3101 of FIG. 50, the main control unit acquires first charging information of each device. When the power transmission device 1 is the main body, in step S3101 the first charging information of each device is acquired as in step S1. When the device is the main body, for example, when the device 2a in FIG. 35 is the main body, step S3101 obtains the first charging information of each device as in step S1701. When the external device 2100 is the main body, in step S3101 the first charging information of each device is acquired in the same manner as in step S2201.

  In step S3102, the main control unit obtains status information of each device.

  When the power transmission device 1 is the main body, for example, the control unit 321 of the power transmission device 1 in FIG. 34 acquires information used to obtain the positional relationship between the power transmission device 1 and each device from the acquisition unit 2801 provided in the power transmission device 1. Then, state information indicating the positional relationship between the power transmission device and the device is obtained.

  When the device is the main body, for example, the control unit 331a of the device 2a in FIG. 35 acquires information used to obtain the positional relationship between the power transmission device 1 and the device from the acquisition unit 2801 provided in the power transmission device 1, and Status information indicating the positional relationship of the devices is obtained. Further, even if an acquisition unit 2801 is provided in each device, each device acquires information used to obtain the positional relationship between the power transmission device 1 and the device, and each information acquired by the control unit 331a of the device 2a is collected. Good.

  When the external device 2100 is the main body, for example, the control unit 2101 in FIG. 40 acquires information used to obtain the positional relationship between the power transmission device 1 and the device from the acquisition unit 2801 provided in the power transmission device 1, and the power transmission device and the device State information indicating the positional relationship is obtained. In addition, an acquisition unit 2801 is provided in each device, each device acquires information used to obtain the positional relationship between the power transmission device 1 and the device, and each information acquired by the control unit 2101 of the external device 2100 is collected. Also good.

  In step S3103, the main control unit estimates the efficiency information of each device using each state information.

  When the power transmission device 1 is the main body, for example, the efficiency calculation unit 2803 of the control unit 321 of the power transmission device 1 in FIG. 34 acquires the state information from the detection unit 2802 of the control unit 321 and estimates the efficiency information of each device. For example, it is conceivable to use the state-efficiency information 2901 stored in the storage unit 322.

  When the device is the main body, for example, the efficiency calculation unit 2803 of the control unit 331a of the device 2a in FIG. 35 acquires state information from the detection unit 2802 of the control unit 331a, and estimates the efficiency information of each device. For example, it may be obtained using the state-efficiency information 2901 stored in the storage unit 332a.

  When the external device 2100 is the main body, for example, the efficiency calculation unit 2803 of the control unit 2101 in FIG. 40 acquires state information from the detection unit 2802 of the control unit 2101 and estimates the efficiency information of each device. For example, it may be obtained using the state-efficiency information 2901 stored in the storage unit 2102.

  In step S3104, the main control unit selects a device other than the device with the maximum second charging power.

  When the power transmission device 1 is the main body, for example, the selection unit 2804 of the control unit 321 of the power transmission device 1 in FIG. 34 obtains the second charging information using the first charging information and the efficiency information acquired from each device.

  When the device is the main body, for example, the selection unit 2804 of the control unit 331a of the device 2a in FIG. 35 obtains the second charging information by using the first charging information and the efficiency information acquired from each device.

  When the external device 2100 is the main body, for example, the selection unit 2804 of the control unit 2101 in FIG. 40 obtains the second charging information by using the first charging information and the efficiency information acquired from each device.

  In step S3105, variable information is obtained by using a combination of a device (a device other than the device having the maximum second charging power) selected by the main control unit and the efficiency information of the selected device.

  When the power transmission device 1 is the main body, for example, the variable information calculation unit 2805 of the control unit 321 of the power transmission device 1 in FIG. 34 obtains variable information from the combination of efficiency information of the selected devices. For example, it may be obtained using the combination information 3001 in FIG. For example, it is conceivable to use the combination information 3001 stored in the storage unit 322.

  When the device is the main body, for example, the variable information calculation unit 2805 of the control unit 331a of the device 2a in FIG. 35 obtains variable information from the combination of efficiency information of the selected device. For example, it is conceivable to use the combination information 3001 stored in the storage unit 332a.

  When the external device 2100 is the main body, for example, the variable information calculation unit 2805 of the control unit 2101 in FIG. 40 obtains variable information from the combination of efficiency information of the selected device. For example, it can be obtained by using the combination information 3001 stored in the storage unit 2102.

  In step S3106, the main control unit transmits a notification for changing the resonance frequency or the Q value of the power reception unit 335 to each of the devices for which variable information is selected. When the power transmission device 1 is the main body, in step S3106, variable information is transmitted to the selected device in the same manner as in step S7. When the device is the main body, for example, when the device 2a of FIG. 35 is the main body, in step S3106, variable information is transmitted to the selected device in the same manner as in step S1707. When the external device 2100 is the main body, in step S3106, charging information for each device is acquired in the same manner as in step S2207.

  In step S3107, the main control unit obtains transmission power.

  When the power transmission device 1 is the main body, for example, the transmission power calculation unit 2806 of the control unit 321 of the power transmission device 1 in FIG. 34 obtains the transmission power using the second charging power of all the devices transmitted from the power transmission device 1. .

  When the device is the main body, for example, when the device 2a in FIG. 35 is the main body, the transmission power calculation unit 2806 of the control unit 331a transmits power using the second charging power of all the devices transmitted from the power transmission device 1. Ask for power.

  When the external device 2100 is the main body, the transmission power calculation unit 2806 of the control unit 2101 obtains the transmission power using the second charging power of all devices transmitted from the power transmission device 1.

  In step S <b> 3108, the main control unit transmits transmission power information to the power transmission device 1. When the power transmission device 1 is the main body, in step S3108, transmission power information is transmitted to the power transmission device 1, and charging is started as described in step S9. When the device is the main body, for example, when the device 2a of FIG. 35 is the main body, in step S3108, the transmission power information is transmitted to the power transmission device 1 in the same manner as in step S1710. Thereafter, charging is started. When the external device 2100 is the main body, in step S3108, transmission power information is transmitted to the power transmission device 1 in the same manner as in step S2209. Thereafter, charging is started.

  According to the fifth embodiment, even when power is supplied to a plurality of devices at the same time, appropriate power can be supplied to devices having different charging power.

  In addition, since the power balance can be adjusted, it is possible to charge a plurality of devices having different charging powers at the same time. In addition, loss during power transmission can be minimized.

  Further, according to the fifth embodiment, the resonance frequency or the Q value can be adjusted according to the power balance to be combined.

  Further, by using the fifth embodiment, it is possible to adjust the resonance frequency or the Q value in accordance with the power balance in consideration of the charging state of the battery and the power distribution of the charging stand in advance.

  A modification will be described.

  A case where transmission power is limited will be described.

  For example, the first charging power of the device A is 5 W, the efficiency information is 0.1, the second charging power is 50 W, the first charging power of the device B is 20 W, the efficiency information is 0.8, and the second A case where the power that can be transmitted from the power transmission device 1 is 50 W when the charging power is 25 W will be described. Since the total of the second charging power of the device A is 50 W and the second charging power of the device B is 25 W, the total is 75 W, so that the power that can be transmitted from the power transmission device 1 is 50 W. Therefore, a ratio 1: 4 in which the first charging power of the device A is 5 W and the first charging power of the device B is 20 W is obtained, and the transmission power 50 W is divided by using this ratio, and the second of the devices A and B is obtained. Find the charging power. The second charging power of the device A is 31.25W, and the second charging power of the device B is 18.75W. That is, the transmission power is divided using the ratio of the first charging power of each device, and the second charging power of each device is obtained. Then, the variable information and the transmission power are obtained using the second charging power of each of the obtained devices.

  According to the modified example, even when the transmission power is limited, appropriate power can be supplied to devices with different charging power.

The power transmission device, the power receiving device, and the power transmission device according to the exemplary embodiments of the present invention have been described above. However, the present invention is not limited to the specifically disclosed embodiments, and may be patented. Various modifications and changes can be made without departing from the scope of the claims.
Regarding the above embodiment, the following additional notes are disclosed.
(Appendix 1)
A power transmission coil that receives power from an AC power source;
A secondary side resonance coil that receives power from the power transmission system coil by electromagnetic induction by magnetic field resonance generated between the power transmission system coil, and a secondary side coil that receives power from the secondary side resonance coil by electromagnetic induction; A power receiving coil having
A first bridge circuit having a switch element connected to the secondary resonance coil;
A first phase detector that detects a first phase of a voltage supplied to the power transmission coil and a second phase of a current flowing through the power reception coil;
A duty ratio of a pulse voltage for driving the switch element of the first bridge circuit, or a phase difference between the first phase and the second phase detected by the first phase detector becomes a first target value or A first resonance frequency control unit configured to vary a resonance frequency of the power reception system coil by varying a phase.
(Appendix 2)
A second bridge circuit having a switch element connected to the primary resonance coil;
A second phase detector that detects a third phase of the voltage supplied to the primary side coil and a fourth phase of the current flowing through the primary side resonance coil;
The duty ratio of the pulse voltage for driving the switch element of the second bridge circuit, or the phase difference between the third phase and the fourth phase detected by the second phase detector becomes a second target value or The power transmission device according to appendix 1, further comprising: a second resonance frequency control unit configured to vary a resonance frequency of the power transmission coil by changing a phase.
(Appendix 3)
The power transmission device according to appendix 1, wherein the first target value is -3π / 2.
(Appendix 4)
The first resonance frequency control unit switches the first target value and sets it to −2π when a degree of coupling between the power transmission coil and the power reception coil increases and a bimodal characteristic appears. 2. The power receiving device according to 2.
(Appendix 5)
The power receiving system coil includes a primary side coil connected to an AC power source and a primary side resonance coil that receives power from the primary side coil by electromagnetic induction, and magnetic resonance generated between the power receiving coil and the power receiving system coil. A power transmission coil for transmitting power to
A bridge circuit having a switch element connected to the primary resonance coil;
A phase detector for detecting a first phase of a voltage supplied to the primary coil and a second phase of a current flowing in the power receiving coil;
By varying the duty ratio or phase of the pulse voltage that drives the switch element of the bridge circuit so that the phase difference between the first phase and the second phase detected by the phase detection unit becomes a target value. And a resonance frequency control unit that varies a resonance frequency of the power transmission coil.
(Appendix 6)
The power transmission device according to appendix 5, wherein the target value is -π.
(Appendix 7)
A secondary side resonance coil that receives power from the power transmission system coil by magnetic field resonance generated between the power transmission system coil that receives power from an AC power source, and a secondary that receives power from the secondary side resonance coil by electromagnetic induction. A power receiving coil having a side coil;
A bridge circuit having a switch element connected to the secondary resonance coil;
A phase detector for detecting a first phase of a voltage supplied to the power transmission coil and a second phase of a current flowing in the power reception coil;
By varying the duty ratio or phase of the pulse voltage that drives the switch element of the bridge circuit so that the phase difference between the first phase and the second phase detected by the phase detection unit becomes a target value. And a resonance frequency control unit that varies a resonance frequency of the power reception coil.
(Appendix 8)
The power receiving device according to appendix 7, wherein the target value is -3π / 2.
(Appendix 9)
The power receiving device according to appendix 8, wherein when the degree of coupling between the power transmission coil and the power receiving coil increases and a bimodal characteristic appears, the target value is switched to -2π.
(Appendix 10)
A power transmission unit disposed in the power transmission device and receiving power from an AC power source;
A secondary side resonance coil that is disposed in a power receiving side device and receives power from the power transmission unit by magnetic field resonance generated between the power transmission unit, and 2 that receives power from the secondary side resonance coil by electromagnetic induction. A power receiving unit having a secondary coil;
A bridge circuit having a switch element connected to the secondary resonance coil;
A charging information generation unit that generates charging information including identification information for identifying a power receiving side device including the power receiving unit, and information indicating charging power of the device;
When a plurality of devices receive power from the power transmission device, when the charging power of the device itself is not maximum, the bridge circuit is based on variable information that varies the resonance frequency or Q value of the resonance circuit of the power reception unit. By varying the duty ratio or phase of the pulse voltage that drives the switch element, the resonance frequency or Q value of the resonance circuit of the power reception unit is set to charge power corresponding to a device other than the device with the maximum charge power, A power transmission device, comprising: a control unit configured to vary a frequency that can be supplied from transmission power transmitted from the power transmission device.
(Appendix 11)
When the charging power of its own device is maximum, the control unit sets the resonance frequency or Q value of the resonance circuit to the transmission frequency of the power transmitted from the primary side resonance coil to the secondary side resonance coil. The power transmission device according to appendix 10, which is set.
(Appendix 12)
In the variable information, when the power reception unit of a plurality of devices receives power from the power transmission unit, the power reception unit of each device receives power from the power transmission unit by magnetic resonance according to the combination of the types of the plurality of devices. 12. The power transmission device according to appendix 10 or 11, which is information representing the degree to which the resonance frequency is varied.
(Appendix 13)
A secondary side resonance coil that receives power from the primary side resonance coil by magnetic field resonance generated between the primary side coil connected to an AC power source and a primary side resonance coil that receives power by electromagnetic induction; A power receiving unit having a secondary side coil that receives power from the secondary side resonance coil by electromagnetic induction;
A bridge circuit having a switch element connected to the secondary resonance coil;
A charging information generating unit that generates charging information including identification information for identifying a power receiving side device including the power receiving unit, and information indicating charging power of the device;
A receiving unit that receives variable information that varies a resonance frequency or a Q value of a resonance circuit included in the power receiving unit from the power transmission device;
When a plurality of devices receive power from the power transmission device, when the charging power of the device itself is not maximum, the bridge circuit is based on variable information that varies the resonance frequency or Q value of the resonance circuit of the power reception unit. By varying the duty ratio or phase of the pulse voltage that drives the switch element, the resonance frequency or Q value of the resonance circuit of the power reception unit is set to charge power corresponding to a device other than the device with the maximum charge power, A power receiving device, comprising: a control unit configured to vary a frequency that can be supplied from the transmitted power transmitted from the power transmitting device.

100, 100B Power transmission system 11 AC power supply 12 Power supply coil 13 Power transmission resonance coil 14 Power transmission side control unit 21 Device 22 Power reception resonance coil 23 Power extraction coil 24 Power reception side control unit 1 Power transmission device 2, 2a, 2b, 2c Equipment 3 Power source Unit 4 power supply coil 5 power transmission resonance coil 6a, 6b, 6c power reception resonance coil 7a, 7b, 7c power extraction coil 321 control unit 322 storage unit 323 communication unit 324 antenna 325 power supply unit 326 power transmission unit 331, 331a, 331b control unit 332, 332a, 332b Storage unit 333, 333a, 333b Communication unit 334, 334a, 334b Antenna 335, 335a, 335b Power reception unit 336 Charging unit 337 Device configuration unit

Claims (4)

Disposed in the power transmitting device, a primary coil connected to an AC power source, a power transmitting unit for chromatic and primary side resonance coil receives power by electromagnetic induction from said primary coil,
A secondary side resonance coil that is disposed in a power receiving side device and receives power from the power transmission unit by magnetic field resonance generated between the power transmission unit and the primary side resonance coil, and electromagnetic induction from the secondary side resonance coil A power receiving unit having a secondary coil for receiving power by
A bridge circuit having a switch element connected to the secondary resonance coil;
A charging information generation unit that generates charging information including identification information for identifying a power receiving side device including the power receiving unit, and information indicating charging power of the device;
In the case where the power transmission apparatus a plurality of said from the device is powered, when the charging power of the own device is not the maximum, the variable information for changing the resonance frequency or the Q value of the resonance circuit included in the power receiving unit of the own device By changing the duty ratio or phase of the pulse voltage that drives the switch element of the bridge circuit based on this, the resonance frequency or Q value of the resonance circuit of the power receiving unit is compatible with devices other than the device with the highest charging power variable to the charging electric power to possible frequency or Q value supplied from the power transmission power of the power transmission device, when the charge power of the own device is a maximum, the duty ratio of the pulse voltage for driving the switching elements of the bridge circuit or And a control unit that fixes a resonance frequency or a Q value of the resonance circuit of the power reception unit by fixing a phase .   When the charging power of its own device is maximum, the control unit sets the resonance frequency or Q value of the resonance circuit to the transmission frequency of the power transmitted from the primary side resonance coil to the secondary side resonance coil. The power transmission device according to claim 1, wherein the power transmission device is set.   In the variable information, when the power reception unit of a plurality of devices receives power from the power transmission unit, the power reception unit of each device receives power from the power transmission unit by magnetic resonance according to the combination of the types of the plurality of devices. The power transmission device according to claim 1, wherein the power transmission device is information representing a degree to which the resonance frequency is varied. A secondary side resonance coil that receives power from the primary side resonance coil by magnetic field resonance generated between the primary side coil connected to an AC power source and a primary side resonance coil that receives power by electromagnetic induction; A power receiving unit having a secondary side coil that receives power from the secondary side resonance coil by electromagnetic induction;
A bridge circuit having a switch element connected to the secondary resonance coil;
A charging information generation unit that generates charging information including identification information for identifying a power receiving side device including the power receiving unit, and information indicating charging power of the device;
A receiving unit that receives variable information that varies a resonance frequency or a Q value of a resonance circuit included in the power receiving unit from a power transmission device;
When a plurality of devices receive power from the power transmission device, when the charging power of the device itself is not maximum, the bridge circuit is based on variable information that varies the resonance frequency or Q value of the resonance circuit of the power reception unit. By varying the duty ratio or phase of the pulse voltage for driving the switch element, the resonance frequency or Q value of the resonance circuit of the power receiving unit is changed to the charging power corresponding to a device other than the device with the largest charging power . When the transmission power of the power transmission device is variable to the frequency or Q value that can be supplied and the charging power of its own device is maximum, the duty ratio or phase of the pulse voltage that drives the switch element of the bridge circuit is fixed. And a control unit that fixes a resonance frequency or a Q value of the resonance circuit of the power reception unit.

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