Wireless power supply system, power transmitter device, control method for power transmitter device, power receiver device, control method for power receiver device, and program

Abstract

A power-transmitter control unit (70) of a power transmitter device (20) calculates an intensity of a power supply request signal based on an output signal of a power-transmitter communication coil (40), and energizes the power transmitter coil (22) when determining that the calculated intensity exceeds a determination threshold. The power transmitter device (20) includes a detection circuit (91) that measures background noise near the power transmitter coil (22). When the measured background noise is large, the power-transmitter control unit (70) sets the determination threshold to a larger value than the determination threshold when the background noise is small. When the measured background noise is large, the power-receiver control unit (230) of the power receiver device (100) sets the intensity of the power supply request signal to be larger than the intensity when the background noise is small.

Description

WIRELESS POWER SUPPLY SYSTEM, POWER TRANSMITTER DEVICE, CONTROL METHOD FOR POWER TRANSMITTER DEVICE, POWER RECEIVER DEVICE, CONTROL METHOD FOR POWER RECEIVER DEVICE, AND PROGRAMCross Reference

[0001] This application is based on Japanese Application No. 2024-208030 filed on November 29, 2024, the contents of which are incorporated herein by reference.

[0002] The present disclosure relates to a wireless power supply system, a power transmitter device, a control method for the power transmitter device, a power receiver device, a control method for the power receiver device, and a program.

[0003] Patent Literature 1 discloses a system for executing wireless power supply from a ground-based power transmitter to a power receiver installed in an electric vehicle. The power transmitter includes a transmitter coil and a controller that energizes the transmitter coil. The power receiver includes a power receiver coil that is supplied with power wirelessly from the power transmitter coil.

[0004] The power transmitter and the power receiver include communication antennas for narrow area wireless communication. The power receiver supplies a power supply request signal to a power-receiver communication antenna of the power receiver. The power transmitter determines whether there is a power supply request based on an output signal from a power-transmitter communication antenna of the power transmitter. When the power transmitter determines that there is a power supply request, the power transmitter energizes the transmitter coil. On the other hand, when the power transmitter determines that there is no power supply request, the power transmitter stops energization of the power transmitter coil.

[0005] JP2024-8088A

[0006] Due to surrounding conditions of the power transmitter coil and the power receiver coil, background noise may be large near at least one of the power transmitter coil and the power receiver coil. In this case, there is a concern that the power-transmitter communication antenna may not be able to properly receive the power supply request signal transmitted from the power-receiver communication antenna. Such an issue may also occur when the power transmitter is a vehicle-side device and the power receiver is a ground-side device.

[0007] It is a main object of the present disclosure to provide a wireless power supply system, a power transmitter device, a control method for the power transmitter device, a power receiver device, a control method for the power receiver device, and a program that enables a power-transmitter communication antenna to properly receive a power supply request signal transmitted from the power-receiver communication antenna, even when background noise near at least one of the transmitting antenna and the receiving antenna is large.

[0008] According to an aspect of the present disclosure, a wireless power supply system is configured to wirelessly supply power from a power transmitter antenna to a power receiver antenna. The wireless power supply system comprises: a power receiver device including the power receiver antenna, a power-receiver communication antenna, and a power-receiver control unit configured to perform energization control of the power-receiver communication antenna to supply a power supply request signal, which indicates power supply request to the power transmitter antenna, to the power-receiver communication antenna; a power transmitter device including the power transmitter antenna, a power-transmitter communication antenna configured to perform wireless communication with the power-receiver communication antenna, and a power-transmitter control unit configured to calculate an intensity of the power supply request signal based on an output signal of the power-transmitter communication antenna, and energize the power transmitter antenna when determining that the calculated intensity exceeds a determination threshold; and a measurement unit configured to measure background noise near at least one of the power transmitter antenna and the power receiver antenna. One of the power receiver device and the power transmitter device is mounted on a vehicle, and the other of the power receiver device and the power transmitter device is a ground-side device. The wireless power supply system is configured to implement at least one of a process executed by the power-transmitter control unit to set, when the measured background noise is large, the determination threshold to be larger than the determination threshold when the measured background noise is small, and a process executed by the power-receiver control unit to set, when the measured background noise is large, an intensity of the power supply request signal supplied to the power-receiver communication antenna to be larger than the intensity when the measured background noise is small.

[0009] This configuration enables, even when the background noise near at least one of the power transmitting antenna and the power receiving antenna is large, the power transmitting side communication antenna can properly receive the power supply request signal transmitted from the power-receiver communication antenna.

[0010] The drawings described herein are intended to illustrate selected embodiments, do not depict all possible embodiments, and are not intended to limit the scope of the present disclosure.

[0011] FIG. 1 is an overall configuration diagram of a wireless power supply system according to a first embodiment.FIG. 2 is an overall configuration diagram of the wireless power supply system.FIG. 3 is a diagram illustrating a power transmitter and a power receiver.FIG. 4 is a diagram illustrating a configuration of wide area wireless communication between the power transmitter and a vehicle.FIG. 5 is a diagram showing a transmitter and its peripheral configuration.FIG. 6 is a diagram showing an example of background noise.FIG. 7 is a flowchart illustrating a process executed by the power transmitter.FIG. 8 is a flowchart illustrating a process executed by the power transmitter.FIG. 9 is a diagram showing an example of a setting mode of a determination threshold.FIG. 10 is a flowchart illustrating a process executed by the power receiver.FIG. 11 is a diagram showing the power transmitter and the power receiver according to a second embodiment.FIG. 12 is a flowchart illustrating a process executed by the power receiver.FIG. 13 is a flowchart illustrating a process executed by the power transmitter.FIG. 14 is a flowchart illustrating a process executed by the power transmitter according to a third embodiment.FIG. 15 is a flowchart illustrating a process executed by the power receiver.FIG. 16 is a flowchart illustrating a process executed by a server and the power receiver according to a fourth embodiment.

[0012] Multiple embodiments will be described with reference to the drawings. In some embodiments, parts that are functionally and / or structurally corresponding to each other and / or associated with each other are given the same reference numerals, or reference numerals with different hundred digit or more digits. The corresponding and / or associated parts may refer to the explanation in the other embodiments.

[0013] First Embodiment A first embodiment of a wireless power supply system of the present disclosure will be described below with reference to the drawings.

[0014] First, an overall configuration of the wireless power supply system will be described. As shown in FIGS. 1, 2, and 3, a wireless power supply system 10 includes a power transmitter 20 and a power receiver 100. The power receiver 100 is mounted on a vehicle 11 as a moving object that travels on a road RS. The vehicle 11 is, for example, an electric automobile or a hybrid vehicle. The power is supplied from the power transmitter 20 to the power receiver 100 while the vehicle 11 is travelling or stopped. The wireless power supply system 10 executes wireless power transfer from the power transmitter 20 to the power receiver 100 through magnetic field resonance coupling (magnetic field resonance). The wireless power supply system 10 is also referred to as a dynamic wireless power transfer (D-WPT) system.

[0015] The power transmitter 20 is a ground-side device and has a power-transmitter coil unit 21 and a power-transmitter power supply unit 51 that supplies power to the power-transmitter coil unit 21. The power transmitter 20 is, for example, a stationary device. The power-transmitter coil unit 21 is installed (for example, buried) in the road RS, a parking lot, or the like. The power-transmitter power supply unit 51 is installed, for example, on the side of the road RS. The power-transmitter coil unit 21 is connected to the power-transmitter power supply unit 51. The power-transmitter power supply unit 51 is connected to an AC power source 15 and supplies AC (alternating-current) power from the AC power source 15 to the power-transmitter coil unit 21. The AC power source 15 is, for example, a commercial power source. Multiple power-transmitter coil units 21 are arranged along the lanes of the road RS. FIG. 2 shows an example of four power-transmitter coil units 21 aligned along the road RS and connected to one power-transmitter power supply unit 51. In other words, one power-transmitter power supply unit 51 is provided for the four power-transmitter coil units 21.

[0016] The configuration is not limited to the singular power-transmitter power supply unit 51 for each of the multiple transmitter coil units 21, but the singular power-transmitter power supply unit 51 may be provided for each power-transmitter coil unit 21.

[0017] The power-transmitter power supply unit 51 includes a PFC (Power Factor Correction) circuit 61, an inverter 60, and a filter circuit 52. The PFC circuit 61 includes an AC / DC converter and is connected to the AC power source 15. The PFC circuit 61 includes switching elements (e.g., IGBTs or MOSFETs) that are switched and controlled to convert the input AC power to DC (direct current) power and improve a power factor of the AC power input from the AC power source 15.

[0018] The inverter 60 is connected to the PFC circuit 61. The inverter 60 includes switching elements (e.g., IGBTs or MOSFETs) that are switched and controlled to convert the DC power input from the PFC circuit 61 to AC power.

[0019] The filter circuit 52 removes noise contained in the AC current input from the inverter 60 and supplies the AC current from which noise has been removed to the power-transmitter coil unit 21. The filter circuit 52 is, for example, an LC filter that includes a coil and a capacitor. Circuits having various configurations can be used as the filter circuit 52, and, for example, a T-type filter circuit is used as the filter circuit 52.

[0020] The power-transmitter coil unit 21 includes a power transmitter coil 22 (corresponding to power transmitter antenna), a power-transmitter resonant circuit 30, and a power-transmitter communication coil 40. The power-transmitter resonant circuit 30 supplies the AC power supplied by the filter circuit 52 to the power transmitter coil 22. The power-transmitter resonant circuit 30 can employ various well-known resonant circuits such as a circuit including a resonant capacitor.

[0021] The power receiver 100 includes a power-receiver coil unit 101 and a power-receiver power supply unit 181. The power-receiver coil unit 101 includes a power receiver coil 102 (corresponding to a "power receiver antenna"). The power-receiver coil unit 101 is located at the bottom of the vehicle body of the vehicle 11. The power-receiver coil unit 101 is located at the bottom of the vehicle body to face the ground surface. When the vehicle 11 travels on the road RS where the power transmitter coil 22 is buried, the power transmitter coil 22 on the ground side and the power receiver coil 102 of the vehicle 11 face each other in the vertical direction.

[0022] The power receiver 100 includes a power-receiver resonant circuit 140. The power receiver coil 102 is connected to the power-receiver resonant circuit 140. The power receiver coil 102 is supplied with power from the power transmitter coil 22. The power receiver coil 102 supplies the received power to the power-receiver resonant circuit 140. The power-receiver resonant circuit 140 may employ various well-known resonant circuits such as a circuit including a resonant capacitor.

[0023] The power receiver 100 includes a filter circuit 182, a rectifier circuit 200 that functions as a DC-AC conversion circuit, and a smoothing capacitor 210. The filter circuit 182 removes noise contained in the AC current input from the power-receiver resonant circuit 140 and supplies the AC current from which noise has been removed to the rectifier circuit 200. The filter circuit 182 of the present embodiment is, for example, an LC filter that includes reactor and a capacitor.

[0024] The rectifier circuit 200 converts the input AC current into a DC current and outputs the DC current. The rectifier circuit 200 is, for example, a full-bridge circuit including semiconductor switching elements, or a diode rectifier circuit. A first end of the smoothing capacitor 210 is connected to a high potential side output terminal of the rectifier circuit 200. A second end of the smoothing capacitor 210 is connected to a low potential side output terminal of the rectifier circuit 200. The rectifier circuit 200 is also referred to as an ERB (Electronic Rectification Box).

[0025] The vehicle 11 includes a high potential main switch 301H, a low potential main switch 301L, and a high-voltage storage battery 300 as a power storage unit. The high potential main switch 301H and the low potential main switch 301L are, for example, relays (specifically, mechanical relays). The high potential side output terminal of the rectifier circuit 200 is connected to a positive terminal of the high-voltage storage battery 300 via the high potential main switch 301H. The low potential side output terminal of the rectifier circuit 200 is connected to a negative terminal of the high-voltage storage battery 300 via the low potential main switch 301L. The high-voltage storage battery 300 is a secondary battery that can be charged and discharged and has a rated voltage of several hundred volts, for example. The high-voltage storage battery 300 is, for example, a lithium-ion storage battery or a nickel-metal hydride storage battery.

[0026] The vehicle 11 includes a travelling inverter 310 and a rotary electric machine 320. The travelling inverter 310 is a 3-phase inverter and is connected to the high-voltage storage battery 300 via the high potential main switch 301H and the low potential main switch 301L. The armature windings of the rotary electric machine 320 are connected to the upper and lower arm switches that constitute the travelling inverter 310. By switching control of the upper and lower arm switches of the travelling inverter 310 while the high potential main switch 301H and the low potential main switch 301L are turned on, the travelling inverter 310 converts the DC power supplied from the high-voltage storage battery 300 into AC power and supplies it to the armature winding. This causes the rotor of the rotary electric machine 320 to rotate, and the rotational power of the rotor rotates wheels 12 (drive wheels) of the vehicle 11. As a result, the vehicle 11 travels.

[0027] As shown in FIG. 3, the power-transmitter power supply unit 51, which constitutes the power transmitter 20, includes a power-transmitter control unit 70. The power-transmitter control unit 70 includes a power-transmitter controller 71. The power-transmitter controller 71 is an electronic control unit (ECU) that executes various controls of the power transmitters 20 and includes, as hardware, a processor, a storage unit, and a communication bus connecting the processor with the storage unit.

[0028] The storage unit includes a memory and a storage as hardware. The memory is a storage device for storing data used in the processing of the power-transmitter controller 71. The memory, for example, provides the processor with a work area for temporary use when the processor performs processing. The memory 212 includes, for example, RAM and ROM. The storage is a storage device that stores various programs and data to be read and executed by the processor and is a non-transitory tangible storage medium. The storage includes, for example, HDD or flash memory. The storage contains program information and other information for the processes described below.

[0029] The power-receiver power supply unit 181, which constitutes the power receiver 100, includes a power-receiver controller 231. The power-receiver controller 231 is an ECU that executes various controls of the power receiver 100, and includes a processor as hardware, a storage unit, and a communication bus that connects the processor and storage unit.

[0030] The storage unit includes a memory and a storage as hardware. The memory is a storage device for storing data used in the processing of the power-receiver controller 231. The memory, for example, provides the processor with a work area for temporary use when the processor performs processing. The memory 212 includes, for example, RAM and ROM. The storage is a storage device that stores various programs and data to be read and executed by the processor and is a non-transitory tangible storage medium. The storage includes, for example, HDD or flash memory. The storage contains program information and other information for the processes described below.

[0031] The power-transmitter controller 71 executes a switching control of the PFC circuit 61 and a switching control of the inverter 60. Through the switching control of the inverter 60, a high-frequency AC voltage is applied to the power transmitter coil 22. This causes a high-frequency current to flow in the power transmitter coils 22 and a magnetic field for power transmission is generated in the power transmitter coils 22.

[0032] In this embodiment, the power-transmitter controller 71 switches and controls the inverter 60 so that the frequency of the high-frequency voltage applied to the power transmitter coil 22 is becomes a first specified frequency between 10 kHz and 100 GHz, specifically, 85 kHz. The resonant frequencies of the power-transmitter resonant circuit 30 and the power-receiver resonant circuit 140 are set at the same frequency or close to the first specified frequency.

[0033] When the magnetic field generated in the power transmitter coil 22 links with the power receiver coil 102 of the vehicle 11, a high-frequency current flows in the power receiver coil 102, varying with the frequency of the high-frequency current flowing in the power transmitter coil 22. The high-frequency current flowing in the power receiver coil 102 is supplied to the rectifier circuit 200 through the power-receiver resonant circuit 140 and the filter circuit 182. The rectifier circuit 200 converts the supplied AC current into a DC current and outputs the DC current. While the high potential main switch 301H and the low potential main switch 301L are turned on, the output current of the rectifier circuit 200 is supplied to the high-voltage storage battery 300 and the travelling inverter 310.

[0034] The vehicle 11 includes a low-voltage storage battery 302. The rated voltage of the low-voltage storage battery 302 is lower than the rated voltage of the high-voltage storage battery 300. The low-voltage storage battery 302 is, for example, a lead-acid battery. The power supplied from the low-voltage storage battery 302 to the power-receiver controller 231 enables the power-receiver controller 231 to operate.

[0035] The power transmitter 20 includes a detection circuit 91. The detection circuit 91 is a measurement unit that measures background noise, which is electrical noise in the vicinity of the power transmitter coil unit 21. The detection circuit 91 may be provided, for example, near a location where the power-transmitter coil unit 21 is buried in the road RS, may be provided on the road RS near the location where the power-transmitter coil unit 21 is buried, or may be built in the power transmitter coil unit 21. The noise detected by the detection circuit 91 is input to the power-transmitter controller 71.

[0036] The power receiver 100 and the power transmitter 20 each have a configuration for communication between the power receiver 100 and the power transmitter 20. In detail, the power-receiver coil unit 101, which constitutes the power receiver 100, includes a power-receiver communication coil 170 (corresponding to a power-receiver communication antenna). A power-receiver control unit 230 includes a signal transmitter 240.

[0037] The power-transmitter coil unit 21, which constitutes the power transmitter 20, includes a power-transmitter communication coil 40 (corresponding to a power-transmitter communication antenna). The power-transmitter control unit 70 includes a signal receiver 80. The power-receiver communication coil 170 and the power-transmitter communication coil 40 are communication coils for narrow area wireless communication. Narrow area wireless communications are those with a communication distance of less than 10 meters (e.g., a maximum of 3 meters). Narrow area wireless communication is a communication with a shorter communication distance than wide area wireless communication.

[0038] Various short-range wireless communications can be used as the narrow area wireless communication. For example, communications compliant with any communication standards established by IEEE, ISO, and IEC can be used. Specifically, for example, Wi-Fi (registered trademark), Bluetooth (registered trademark), ZigBee (registered trademark), RFID (Radio Frequency Identification), or DSRC (Dedicated Short Range Communication) can used as the narrow area wireless communication.

[0039] The signal transmitter 240 is connected to the power-receiver controller 231. the signal transmitter 240 is connected to the power-receiver communication coil 170. The power-receiver controller 231 controls the signal transmitter 240 to supply a power supply request signal COMM to the power-receiver communication coil 170. The power supply request signal COMM is a signal requesting the power transmitter coil 22 near the vehicle 11 to transmit power to the power receiver coil 102.

[0040] The power-receiver control unit 230 controls the signal transmitter 240 to supply information including a power supply request signal COMM and a traveling speed of the vehicle 11 in one frame to the power-receiver communication coil 170. In this embodiment, the power supply request signal includes ID information of the vehicle 11 and a requested power Weq that is a requested value of power to be supplied to the vehicle 11. This control causes a high-frequency voltage to be applied from the signal transmitter 240 to the power-receiver communication coil 170. Consequently, a high-frequency current flows in the power-receiver communication coil 170, and a magnetic field for information communication is generated in the power-receiver communication coil 170.

[0041] When the power-receiver coil unit 101 of the vehicle 11 approaches the power-transmitter coil unit 21 on the ground side, the magnetic field generated by the power-receiver communication coil 170 links to the power-transmitter communication coil 40, and a high-frequency current flows through the power-transmitter communication coil 40. This high-frequency current is input to the signal receiver 80. the signal receiver 80 recognizes the presence or absence of a power supply request and ID information based on the input signal from the power-transmitter communication coil 40. the signal receiver 80 also acquires the requested power Weq for the vehicle 11 with the recognized ID information, based on the signal from the power-transmitter communication coil 40. The information recognized by the signal receiver 80 and the requested power Weq are input to the power-transmitter controller 71.

[0042] In this embodiment, the power-receiver controller 231 controls the signal transmitter 240 so that the frequency of the high-frequency voltage applied to the power-receiver communication coil 170 becomes a second specified frequency between 10 kHz and 100 GHz. In this embodiment, the second specified frequency is a frequency that deviates from the first specified frequency above, specifically a frequency higher than the first specified frequency (e.g., 13. 56 MHz).

[0043] The power-transmitter controller 71 determines whether to energize the power transmitter coil 22 based on the input signal from the signal receiver 80. In detail, when the power-transmitter controller 71 determines that there is the power supply request based on the input signal from the signal receiver 80, the power-transmitter controller 71 applies high-frequency voltage to the power transmitter coil 22 by performing switching control of the inverter 60 and the PFC circuit 61. This results in a wireless power transmission from the power transmitter coil 22 to the power receiver coil 102.

[0044] FIG. 4 is a schematic diagram for explaining wide area wireless communication in the wireless power supply system 10. In the wireless power supply system 10, each vehicle 11 is capable of communicating with each power transmitter 20 via a communication network 16. The communication network 16 includes, for example, a WAN (Wide Area Network), which is a public communication network such as the Internet, a telephone communication network for a mobile phone, an information and communication network for ETC, and an information and communication network for a Vehicle Information and Communication System (VICS (registered trademark)). Wide area wireless communication is a communication with a longer communication distance than the narrow area wireless communication. Wide area wireless communication is communication with a communication distance of, for example, 10 meters to 10 kilometers. Examples of the wide area wireless communication include 3GPP (registered trademark), 4G, LTE, 5G, and WiMAX (registered trademark) developed by IEEE.

[0045] The vehicle 11 is equipped with a position sensor 330, a navigation device 331, and a communication unit 332. The position sensor 330 is a sensor that detects the current position of the vehicle, and is, for example, a GPS sensor. A storage unit (for example, storage) of the navigation device 331 stores map information including road information. The navigation device 331 receives information on the current position of the vehicle detected by the position sensor 330 and weather information. The power-transmitter control unit 70 of the power transmitter 20 includes a communication unit 90. The communication unit 332 of the vehicle 11 and the communication unit 90 of the power-transmitter control unit 70 perform wide area wireless communication via the communication network 16.

[0046] The wireless power supply system 10 includes a server 400. The server 400 is, for example, a cloud server, and includes a server controller 401 and a communication unit 402. The server controller 401 is an electronic control unit (ECU) that executes various controls of the server 400 and includes a processor as hardware, a storage unit, and a communication bus connecting the processor and storage unit. The storage unit includes a memory and a storage as hardware. The memory is a storage device for storing data used in the processing of the server controller 401. The memory, for example, provides the processor with a work area for temporary use when the processor performs processing. The memory 212 includes, for example, RAM and ROM. The storage is a storage device that stores various programs and data to be read and executed by the processor and is a non-transitory tangible storage medium. The storage includes, for example, HDD or flash memory. The storage contains program information and other information for the processes described below.

[0047] The server controller 401 is connected to the communication unit 402. The server controller 401 performs wide area wireless communication with the communication unit 332 of the vehicle 11 and the communication unit 90 of the power-transmitter control unit 70 via the communication unit 402 and the communication network 16.

[0048] For example, the program information stored on the non-transitory tangible storage medium is installed in the storage units of the power-receiver controller 231, power-transmitter controller 71, and the server controller401. The storage medium is, for example, a USB memory, CD-ROM or DVD. In addition, program information transmitted over a communication network 16, such as OTA (Over The Air), is installed in the storage units.

[0049] Next, the signal transmitter 240 and its peripheral configuration will be described with reference to FIG. 5.

[0050] the signal transmitter 240 includes a generating circuit 241, and a power-receiver amplifier 242. The generating circuit 241 is connected to the power-receiver controller 231 and the power-receiver amplifier 242. The generating circuit 241 generates a vehicle-side signal, which is a high-frequency signal including a power supply request signal, based on a command from the power-receiver controller 231. The frequency of the vehicle-side signal is the second specified frequency. The power-receiver amplifier 242 amplifies the high-frequency signal generated by the generating circuit 241 and supplies the amplified signal to the power-receiver communication coil 170.

[0051] The power-receiver controller 231 instructs the generating circuit 241 to generate a vehicle-side signal. The high-frequency signal output from the generating circuit 241 is amplified by the power-receiver amplifier 242. The amplified signal is supplied to the power-receiver communication coil 170.

[0052] The signal receiver 80 and its peripheral configuration will be described.

[0053] The signal receiver 80 amplifies a high-frequency signal (high-frequency current signal or high-frequency voltage signal) output from the power-transmitter communication coil 40. The high-frequency signal output from the power-transmitter communication coil 40 contains a frequency component that fluctuates at the second specified frequency.

[0054] the signal receiver 80 detects the amplified high-frequency signal and calculates an intensity Intd, which is an amplitude or an effective value of the input power supply request signal. When determining that the calculated intensity Intd exceeds a determination threshold Ijde, the signal receiver 80 determines that there is the power supply request. On the other hand, when determining that the calculated intensity Intd is below a determination threshold Ijde, the signal receiver 80 determines that there is non power supply request. The determination result information of the signal receiver 80 is input to the power-transmitter controller 71.

[0055] When determining that there is no power supply request based on the input determination result information, the power-transmitter controller 71 stops the switching control of the PFC circuit 61 and the inverter 60. As a result, the switches of the PFC circuit 61 and the inverter 60 are kept off, and the power transmitter coil 22 is not energized.

[0056] On the other hand, on condition that it is determined that there is a power supply request based on the determination result information, the power-transmitter controller 71 applies a high frequency voltage to the power transmitter coil 22 by performing switching control of the PFC circuit 61 and the inverter 60. This causes a high-frequency current to flow through the power transmitter coil 22. In this case, wireless power supply from the power transmitter coil 22 to the power receiver coil 102 that faces the power transmitter coil 22 in the vertical direction is performed. In addition, when the power-transmitter controller 71 determines that there is a power supply request, it actually performs a coupling determination process prior to executing the switching control of the inverter 60 and the PFC circuit 61 to determine whether the degree of magnetic coupling between the power receiver coil 102 and the power transmitter coil 22 is appropriate for power transmission. The power-transmitter controller 71 executes the switching control of the inverter 60 and the PFC circuit 61 on condition that the power-transmitter controller 71 has determined that the degree of magnetic coupling between the power receiver coil 102 and the power transmitter coil 22 is appropriate. As a result, the power transmitter coil 22 is energized while the power receiver coil 102 and the power transmitter coil 22 are in close proximity to each other.

[0057] Herein, depending on the surrounding conditions of the power-transmitter coil unit 21, background noise near the power-transmitter coil unit 21 may be large. A background noise level is a magnitude of electrical noise (specifically, magnitude of magnetic field strength or electric field strength) measured when a target device whose noise is to be measured is not in operation, and has a unit of [dBμV / m] or [dBμA / m], as shown in FIG. 6. When the background noise is large, there is a concern that the power-transmitter communication coil 40 cannot properly receive the power supply request signal transmitted from the power-receiver communication coil 170.

[0058] Therefore, when the background noise measured by the detection circuit 91 is large, the power-transmitter control unit 70 of the present embodiment sets a determination threshold Ijde to be larger than the determination threshold Ijde when the background noise is small. Furthermore, when the measured background noise is large, the power-receiver control unit 230 sets the intensity of the power supply request signal to be larger than the intensity when the background noise is small.

[0059] FIG. 7 is a flowchart of the process executed by the power-transmitter control unit 70 of each power-transmitter power supply unit 51 installed on the ground.

[0060] In step S10, the signal receiver 80 calculates the intensity Intd of the power supply request signal based on the high-frequency signal input from the power-transmitter communication coil 40.

[0061] In step S11, the signal receiver 80 determines whether the calculated intensity Intd exceeds the determination threshold Ijde. The determination result of the signal receiver 80 is input to the power-transmitter controller 71.

[0062] When acquiring a determination result that the calculated intensity Intd exceeds the determination threshold Ijde, the power-transmitter controller 71 proceeds to step S12. In step S12, the power-transmitter controller 71 determines that there is the power supply request, and energizes the power transmitter coil 22 that is a target of energization control by the power-transmitter controller 71. That is, the power-transmitter controller 71 performs switching control of the inverter 60 and the PFC circuit 61 that are targets of energization control by the power-transmitter controller 71.

[0063] On the other hand, when acquiring a determination result that the calculated intensity Intd is lower than the determination threshold Ijde, the power-transmitter controller 71 determines that there is no power supply request, and proceeds to step S13. In step S13, the power-transmitter controller 71 does not energize the power transmitter coil 22 that is a target of energization control by the power-transmitter controller 71. In other words, the power-transmitter controller 71 does not perform switching control of the inverter 60 and the PFC circuit 61 that are targets of energization control by the power-transmitter controller 71, and keeps the switches of the inverter 60 and the PFC circuit 61 turned off.

[0064] FIG. 8 is a flowchart of the process executed by the power-transmitter control unit 70 of each power-transmitter power supply unit 51 installed on the ground.

[0065] In step S20, the power-transmitter controller 71 determines whether a measurement condition of background noise is satisfied. The measurement condition in this embodiment includes a first condition and a second condition. The first condition is that no vehicle is present near the power-transmitter coil unit 21 and the detection circuit 91. The power-transmitter controller 71 may, for example, receive information on the current position of the vehicle detected by the position sensor 330 by wide area wireless communication, and may determine whether a vehicle is present near the power-transmitter coil unit 21 and the detection circuit 91 based on the received position information. According to the first condition, an accuracy of detecting the background noise can be improved.

[0066] The second condition is that the switching control of the inverter 60 and the PFC circuit 61 is stopped, and the power transmitter coil 22 is not energized. In other words, the second condition is a condition that the power supply control of the power transmitter coil 22 is not executed.

[0067] When determining that both the first and second conditions are satisfied, the power-transmitter controller 71 determines that the measurement condition is satisfied, and proceeds to step S21. In step S21, the power-transmitter controller 71 acquires the background noise measured by the detection circuit 91. The acquired background noise is a background noise level in a measurement frequency range of the background noise. The acquired background noise is a background noise due to electrical noise (specifically, magnitude of magnetic field strength or electric field strength) resulting from the current control of the power transmitter coil 22 and electrical noise (specifically, magnitude of magnetic field strength or electric field strength) resulting from a vehicle traveling near the power-transmitter coil unit 21. In other words, the acquired background noise is a background noise relative to electrical noise resulting from the operation of the inverter 60 and the PFC circuit 61 and electrical noise resulting from a vehicle traveling near the power-transmitter coil unit 21.

[0068] In step S22, when the acquired background noise level is high, the power-transmitter controller 71 sets the determination threshold Ijde used in step S11 in FIG. 7 to a value larger than the determination threshold Ijde when the acquired background noise level is low. Specifically, the power-transmitter controller 71 continually or stepwisely increases the determination threshold Ijde, as the acquired background noise level increases.

[0069] Furthermore, the power-transmitter controller 71 sets the determination threshold Ijde to be greater than the acquired background noise level. In more detail, for example, as shown in FIG. 9, the power-transmitter controller 71 sets the determination threshold Ijde to be greater than a maximum value of the acquired background noise level BNd in the measurement frequency range of the background noise. In addition, for example, the power-transmitter controller 71 calculates an overall value of the background noise level in the measurement frequency range, and sets the determination threshold Ijde to be greater than the calculated overall value. This configuration enables to prevent the determination threshold Ijde from being buried in the background noise, thereby improving the accuracy of determining whether there is the power supply request.

[0070] In step S23, the power-transmitter controller 71 transmits the information on the background noise acquired in step S21 to the power receiver 100 of the vehicle 11 by wide area wireless communication. Specifically, the power-transmitter controller 71 transmits information on the background noise including the acquired measurement position information on the background noise.

[0071] FIG. 10 is a flowchart of the process executed by the power-receiver control unit 230 of each vehicle 11. The process of FIG. 10 is executed while the vehicle 11 travels or stops.

[0072] In step S30, the power-receiver controller 231 determines whether the information on the background noise transmitted in the process of step S23 is received.

[0073] When the power-receiver controller 231 determines that information on the background noise is received, the process proceeds to step S31. In step S31, the power-receiver controller 231 performs a gain adjustment process based on the received information on the background noise to increase a gain of the power receiving side amplifier 242 when the background noise level is high compared to when the background noise level is low. For example, the power-receiver controller 231 increases the gain as the background noise level increases. As a result, as the background noise level becomes larger, the intensity of the power supply request signal transmitted from the power-receiver communication coil 170 becomes larger. The power-receiver controller 231 may adjust the gain based on gain adjustment information stored in the storage unit. The gain adjustment information is map information or formula information in which the background noise level is associated with the gain corresponding to the background noise level.

[0074] In step S31, when determining that the current position of the vehicle 11 (subject vehicle) detected by the position sensor 330 is near the measurement position of the background noise received in step S30, the power-receiver controller 231 may perform the gain adjustment processing. The current position of the subject vehicle is determined to be in the vicinity of the measurement position when, for example, the measurement position is within a predetermined radius Lm centered on the subject vehicle. The predetermined radius Lm satisfies, for example, "10m ≦ Lm ≦ 100m", "30m ≦ Lm ≦ 100m", or "50m ≦ Lm ≦ 100m".

[0075] According to the present embodiment described above, the background noise is measured by the microphones 91 of the power transmission devices 20 installed in various locations, and information on the measured background noise is shared by the power receivers 100 of multiple vehicles 11. As a result, when each vehicle 11 travels near the power-transmitter coil unit 21, even when the background noise near the power-transmitter coil unit 21 is high, the power-transmitter communication coil 40 can properly receive the power supply request signal transmitted from the power-receiver communication coil 170.

[0076] Modification of First Embodiment The information on the background noise transmitted from the power-transmitter control unit 70 to the power-receiver control unit 230 is not limited to the background noise level (in other words, absolute value of background noise), and may be, for example, a difference of the measured background noise level from a reference level of electrical noise, information about which of multiple noise level ranges (e.g., three ranges) the measured background noise level falls within, or information on a command intensity of the power supply request signal to the power-receiver control unit 230.

[0077] Based on the ID information of the vehicle extracted based on the output signal of the power-transmitter communication coil 40, the power-transmitter controller 71 acquires vehicle gap information included in the ID information. The gap is a height position of the power-receiver communication coil 170 relative to the surface of the road RS. When the gap is large, the power-transmitter controller 71 may set the determination threshold Ijde to be smaller than the determination threshold Ijde when the gap is small. A vehicle with a small gap is, for example, a sports car. A vehicle with a large gap is, for example, a sport utility vehicle (SUV) or a truck.

[0078] In step S23, the power-transmitter controller 71 may include information on a measurement time of the background noise in the information to be transmitted to the power receiver 100. In this case, in step S31, when determining that the current position of the vehicle is near the measurement position of the background noise received in step S30 and that the current time is near the received measurement time, the power-receiver controller 231 may perform the gain adjustment processing.

[0079] Second Embodiment Hereinafter, a second embodiment will be described with reference to the drawings, focusing on differences from the first embodiment. In this embodiment, as shown in FIG. 11, the power receiver 100 includes a detection circuit 341. More specifically, the power-receiver coil unit 101 includes the detection circuit 341. The detection circuit 341 is provided in consideration of that the background noise near the power-receiver coil unit 101 may be large due to the surrounding condition of the power-receiver coil unit 101, and the like. The detection circuit 341 may be provided in a portion of the vehicle 11 other than the power-receiver coil unit 101.

[0080] FIG. 12 is a flowchart of the process executed by the power-receiver control unit 230 of each vehicle 11. The process of FIG. 12 is executed while the vehicle 11 travels or stops.

[0081] In step S40, the power-receiver controller 231 determines whether a measurement condition of background noise is satisfied. The measurement condition is, for example, that a predetermined period has elapsed since the background noise of the subject vehicle was previously measured.

[0082] When determining that the measurement condition is satisfied, the power-receiver controller 231 proceeds to step S41 and determines whether the vehicle-side signal including the power supply request signal is being supplied to the power-receiver communication coil 170.

[0083] When determining that the vehicle-side signal is not being supplied, the power-receiver controller 231 proceeds to step S43 and acquires the background noise measured by the detection circuit 341. The acquired background noise is a background noise caused by electrical noise (specifically, magnitude of magnetic field strength or electric field strength) resulting from the energization control of the power-receiver communication coil 170. In other words, the acquired background noise is a background noise relative to the electrical noise resulting from the operation of the signal transmitter 240. During a period in which no vehicle-side signal is supplied to the power-receiver communication coil 170, the background noise is measured. This configuration enables to improve the accuracy of measurement of the background noise.

[0084] On the other hand, when determining that the vehicle-side signal is being supplied, the power-receiver controller 231 proceeds to step S42 and performs a process to temporarily stop the supply of the vehicle-side signal from the signal transmitter 240 to the power-receiver communication coil 170. Then, the power-receiver controller 231 proceeds to step S 43 and obtains the background noise measured by the detection circuit 341. This configuration enables to measure the background noise during the period in which the supply of the vehicle-side signals to the power-receiver communication coil 170 is temporarily stopped. This configuration enables to improve the accuracy of measurement of the background noise.

[0085] In step S43, the power-receiver controller 231 transmits the information on the background noise acquired in step S43 to each power transmitter 20 by wide area wireless communication or short area wireless communication. Specifically, the power-receiver controller 231 transmits the information on the background noise including the acquired measurement position information on the background noise.

[0086] In step S45, the power-receiver controller 231 performs the gain adjustment process based on the information on the background noise acquired in step S43 in a manner similar to step S31 of FIG. 10.

[0087] FIG. 13 is a flowchart of the process executed by the power-transmitter control unit 70 of each power-transmitter power supply unit 51 installed on the ground.

[0088] In step S50, the power-transmitter controller 71 determines whether the information on the background noise transmitted in the process of step S44 is received.

[0089] When determining that the information on the background noise has been received, the power-transmitter controller 71 proceeds to step S51, where the power-transmitter controller 71 sets the determination threshold Ijde in a manner similar to step S22 of FIG. 8. Specifically, when the power-transmitter controller 71 determines, based on the information on the received background noise, that the measurement position of the background noise is near the power-transmitter coil unit 21 that is the target of the energization control of the power-transmitter controller 71, the power-transmitter controller 71 sets the determination threshold Ijde in a manner similar to step S22.

[0090] The power-transmitter controller 71 may set the determination threshold Ijde based on threshold adjustment information stored in the storage unit. The threshold adjustment information is map information or formula information in which the background noise level is associated with the threshold Ijde corresponding to the background noise level.

[0091] Third Embodiment Hereinafter, a third embodiment will be described with reference to the drawings, focusing on differences from the first embodiment. In this embodiment, measurement information on the background noise associated with the measurement location and the measurement time band is transmitted to each vehicle. The power-receiver control unit 230 of a target vehicle, which is the vehicle that receives the measurement information, sets the intensity of the power supply request signal based on the received background noise.

[0092] FIG. 14 is a flowchart of the process executed by the power-transmitter control unit 70 of each power-transmitter power supply unit 51 installed on the ground.

[0093] When determining in step S20 that the measurement condition is satisfied, the power-transmitter controller 71 proceeds to step S24. In step S24, the power-transmitter controller 71 acquires the background noise measured by the detection circuit 91. The power-transmitter controller 71 associates the acquired background noise with the measurement location and the measurement time band and stores the associated information in the storage unit of the power-transmitter controller 71.

[0094] In step S25, the power-transmitter controller 71 associates the background noise acquired in step S24 with the measurement location and the measurement time band, and transmits the associated information to the power receiver 100 of each vehicle by wide area wireless communication as shown in FIG. 4. The process of step S25 corresponds to a "processing unit".

[0095] FIG. 15 is a flowchart of the process executed by the power-receiver control unit 230 of each vehicle 11. The process of FIG. 15 is executed while the vehicle 11 travels or stops.

[0096] When determining in step S30 the power-receiver controller 231 receives information on the background noise, the power-receiver controller 231 proceeds to step S32. In step S32, the power-receiver controller 231 stores, in its storage unit, the information on the background noise received in step S30 and associated with the measurement location and the measurement time band. Each time new information on the background noise is transmitted from the power transmitter 20, the new background noise information is stored in the storage unit of the power-receiver controller 231, and the information on the background noise associated with the measurement location and the measurement time band, which has already been stored, is updated.

[0097] In the next step S33, the power-receiver controller 231 determines whether there is information on the measurement location, which includes the information on the current position of the vehicle detected by the position sensor 330, and the measurement time band, which includes the information on the current time acquired from the navigation device 331 or the like and associated with the measurement location including the information on the current position, in the stored information in the storage unit. The process of step S33 is a process to determine whether the vehicle travels in the measurement location included in the stored information in the storage unit in the measurement time band included in the stored information in the storage unit.

[0098] When the determination in step S33 is affirmative, the power-receiver controller 231 proceeds to step S34, where the power-receiver controller 231 associates the measurement location including the information on the current position of the vehicle and the measurement time band including the information on the current time, and performs the gain adjustment process similar to step S31 in FIG. 10 based on the background noise stored in the memory unit.

[0099] The present embodiment described above enables to set an appropriate intensity of the power supply request signal according to the measurement location and the measurement time band of the background noise.

[0100] Modification of Third Embodiment The power-transmitter controller 71 may transmit information on the background noise associated with the measurement location and the measurement time band to the server 400 by wide area wireless communication. In this case, the server controller 401 of the server 400 may store the received information on the background noise in its storage unit, and may transmit the information on the background noise to each vehicle by wide-area wireless communication.

[0101] Fourth Embodiment Hereinafter, the fourth embodiment will be described with reference to the drawings, focusing on the differences from the above-described embodiments. In this embodiment, a transmission prevention command to prevent the power supply request signal in a specific location and in a specific time band is transmitted to the power receiver 100 of each vehicle. The power-receiver control unit 230 of the power receiver 100, which receives the transmission prevention command, stops supply of the power supply request signal to the power-receiver communication coil 170 when the vehicle in which the power receiver 100 is installed travels in the specific location during the specific time band. The detection circuit 91 and 341 located at the particular location measures the background noise in the particular time band.

[0102] FIG. 16 is a flowchart of a process executed by the server controller 401 of the server 400 and the power-receiver controller 231 of the power receiver 100.

[0103] In step S60, the server controller 401 transmits the transmission prevention command of the power supply request signal, which includes information on the specific location and the specific time band in which the background noise is to be measured, to the power receiver 100 of each vehicle by wide-area wireless communication. The specific time band is, for example, a time band of about several minutes at night when traffic volume is low. The process of step S60 corresponds to the "prevention unit".

[0104] In step S70, the power-receiver controller 231 of the power receiver 100 determines whether the transmission prevention command is received.

[0105] When determining in step S70 that the transmission prohibition command is received, the power-receiver controller 231 proceeds to step S71 and stores the information on the specific location and the specific time band included in the received transmission prevention command information in its storage unit. Every time new transmission prevention command is transmitted from the power transmitter 20, new information on the specific location and the specific time band is stored in the storage unit of the power-receiver controller 231. The power-receiver controller 231 may execute a process to delete information on the specific location and the specific time period whose validity period has expired from the storage unit.

[0106] In step S72, the power-receiver controller 231 determines whether there is information on the specific location, which includes the information on the current position of the vehicle detected by the position sensor 330, and the specific time band, which includes the information on the current time acquired from the navigation device 331 or the like and associated with the specific location including the information on the current position, in the stored information in the storage unit. The process of step S72 is a process to determine whether the vehicle travels in the specific location included in the stored information in the storage unit in the specific time band included in the stored information in the storage unit.

[0107] When the determination in step S72 is affirmative, the power-receiver controller 231 proceeds to step S73 and instructs the generating circuit 241 to stop generation of the vehicle-side signal. This stops the transmission of the power supply request signal.

[0108] In the wireless power supply system 10, the detection circuit 91 and 341 present at the specific location measures the background noise in the specific time band.

[0109] For example, the third and fourth conditions are added to the measurement condition in step S20 in FIGS. 8 and 14 of the first and third embodiments. The third condition is that the installation location of the power-transmitter coil unit 21 that is the control target of the power-transmitter control unit 70 is not included in the specific location received by the power-transmitter control unit 70 from the server 400 by wide area wireless communication. The fourth condition is that the current time is not included in the specific time band received by the power-transmitter control unit 70 from the server 400 by wide area wireless communication. When determining that all of the first to fourth conditions are satisfied, the power-transmitter controller 71 determines that the measurement condition is satisfied.

[0110] Further, for example, in step S40 of FIG. 12 in the second embodiment, the power-receiver controller 231 determines whether both the fifth and sixth conditions are satisfied. The fifth condition is that the current position of the vehicle detected by the position sensor 330 is not include in the specific location received by the power-receiver control unit 230 from the server 400 by wide area wireless communication. The sixth condition is that the current time is not included in the specific time band received by the power-receiver control unit 230 from the server 400 by wide area wireless communication. When determining that both of the fifth to sixth conditions are satisfied, the power-receiver controller 231 determines that the measurement condition is satisfied.

[0111] The present embodiment described above enables to improve an accuracy of measurement of the background noise.

[0112] Other Embodiments The above embodiments may be modified and carried out as follows.

[0113] In the fourth embodiment, the transmission prevention command may be transmitted from each power-transmitter control unit 70 to the power receiver 100 of each vehicle by wide area wireless communication.

[0114] The power transmitter 20 may include the detection circuit 91, and the power receiver 100 may include the detection circuit 341. In this case, for example, the process of the first embodiment and the process of the second embodiment may be executed in combination.

[0115] The non-contact power supply system may execute one of the process to set, when the measured background noise is large, the determination threshold to be larger than the determination threshold when the measured background noise is small, and the process to set, when the measured background noise is large, the intensity of the power supply request signal to be larger than the intensity when the background noise is small.

[0116] The wireless power supply system may have the first function of wirelessly supplying power from the vehicle-side device to the ground-side device, in addition to the second function of wirelessly supplying power from the ground-side device to the vehicle-side device. In this case, the in-vehicle power receiver 100 has a power transmitting function in addition to the power receiving function. Moreover, the power transmitter 20 on the ground side has a power receiving function in addition to the power transmitting function. The second function will be described below with reference to FIG. 3.

[0117] The power-receiver controller 231 applies a high frequency AC voltage to the power receiver coil 102 by controlling the switching of the rectifier circuit 200. This causes a high-frequency current to flow in the power receiver coil 102, and a magnetic field for power transmission is generated in the power receiver coil 102.

[0118] When the magnetic field generated in the power receiver coil 102 links with the power transmitter coil 22, a high-frequency current flows in the power transmitter coil 22, varying with the frequency of the high-frequency current flowing in the power receiver coil 102. The high-frequency current flowing through the power transmitter coil 22 is supplied to the AC power source 15 via the power-transmitter resonant circuit 30, the filter circuit 52, the inverter 60 and the PFC circuit 61. In this case, the power-transmitter controller 71 controls the switching of the inverter 60 and the PFC circuit 61.

[0119] In the wireless power supply system having the second function, for example, the power transmitter 20 may include a transmitter that supplies a power supply request signal to the power-transmitter communication coil 40. Furthermore, the power receiver 100 may include a receiver that receives the power supply request signal received by the power-receiver communication coil 170 and inputs the information to the power-receiver controller 231.

[0120] The wireless power supply system may have the function of wirelessly supplying power from the vehicle-side device to the ground-side device, instead of the function of wirelessly supplying power from the ground-side device to the vehicle-side device.

[0121] The power-receiver communication antenna and the power-transmitter communication antenna are not limited to communication coils, and may employ various antennas. For example, the communication antenna is a dipole antenna or a monopole antenna.

[0122] The method of wireless power transmission by the power transmitter antenna and the power receiver antenna is not limited to the magnetic field resonance method, and may be an electric field coupling method. In this case, a power transmitter antenna and a power receiver antenna that are different in form from coils and use an electric field coupling method may be used.

[0123] The vehicle identification information used in the processes of the above embodiments is not limited to vehicle ID information, and may be, for example, a token or credit card information of a vehicle user.

[0124] The vehicle on which the power receiver 100 is mounted is not limited to a vehicle traveling on the road RS, but may be, for example, an AGV (Automated Guided Vehicle) or a traveling robot. In this case, the power-transmitter coil unit 21 is not buried in the road RS, but may be installed on a sidewalk adjacent to the road RS, in a parking lot, or in the path along which the AGV travels.

[0125] The control units and methods thereof described in the present disclosure may be implemented by a dedicated computer including a processor programmed to execute one or more functions embodied by a computer program and a memory. Alternatively, the control units and the methods thereof described in the present disclosure may be implemented by a dedicated computer including a processor with one or more dedicated hardware logic circuits. Alternatively, the control circuit and method described in the present disclosure may be realized by one or more dedicated computer, which is configured as a combination of a processor and a memory, which are programmed to perform one or more functions, and a processor which is configured with one or more hardware logic circuits. The computer programs may be stored, as instructions to be executed by a computer, in a tangible non-transitory computer-readable medium.

[0126] Although the present disclosure has been described according to the embodiments, it is understood that the present disclosure is not limited to the above-described embodiments or structures. To the contrary, the present disclosure is intended to cover various modification and equivalent arrangements. Furthermore, although various combinations and modes are described in the present disclosure, the scope and idea of the present disclosure further include other combinations and modes including only one element, more elements, or less elements in these. When the power transmitter device includes multiple power transmitter devices, determination whether the intensity exceeds the determination threshold may be made by a part of the power transmitter devices or by all the power transmitter devices. In this case, information acquired by the power transmitter devices may be commonly shared. Basically, the background noise is measured when the vehicle does not exist. Confirmation whether the vehicle does not exist may be made based on a GPS signal and a power supply history in a crowd system. A time when the vehicle does not exist may be determined in advance, and the background noise may be measured at the determined time in another day. A big data may be utilized. When the measurement is implemented actually, confirmation whether the power supply is not implemented may be made with reference to the big data to make sure.

Claims

A wireless power supply system configured to wirelessly supply power from a power transmitter antenna to a power receiver antenna, the wireless power supply system comprising:a power receiver device (100) includingthe power receiver antenna (102),a power-receiver communication antenna (170), anda power-receiver control unit (230) configured to perform energization control of the power-receiver communication antenna to supply a power supply request signal, which indicates power supply request to the power transmitter antenna, to the power-receiver communication antenna;a power transmitter device (20) includingthe power transmitter antenna (22),a power-transmitter communication antenna (40) configured to perform wireless communication with the power-receiver communication antenna, anda power-transmitter control unit (70) configured tocalculate an intensity of the power supply request signal based on an output signal of the power-transmitter communication antenna, andenergize the power transmitter antenna when determining that the calculated intensity exceeds a determination threshold; anda measurement unit (91, 341) configured to measure background noise near at least one of the power transmitter antenna and the power receiver antenna, whereinone of the power receiver device and the power transmitter device is mounted on a vehicle (11), and the other of the power receiver device and the power transmitter device is a ground-side device, andthe wireless power supply system is configured to implement at least one ofa process executed by the power-transmitter control unit to set, when the measured background noise is large, the determination threshold to be larger than the determination threshold when the measured background noise is small, anda process executed by the power-receiver control unit to set, when the measured background noise is large, an intensity of the power supply request signal supplied to the power-receiver communication antenna to be larger than the intensity when the measured background noise is small.The wireless power supply system according to claim 1, whereinthe power-transmitter control unit is configured toexecute the process to set, when the measured background noise is large, the determination threshold to be larger than the determination threshold when the measured background noise is small, andset the determination threshold to be larger than the measured background noise.The wireless power supply system according to claim 1 or 2, whereinthe measurement unit (91) is provided to the power transmitter device,the power transmitter device is configured to transmit information on the measured background noise to the power receiver device, andthe receiver control unit is configured to, when the measured background noise is large based on the received information on the background noise, set the intensity of the power supply request signal to be larger than the intensity when the background noise is small.The wireless power supply system according to claim 3, whereinin the power transmitter device, the measurement unit is configured to measure the background noise when no vehicle is present near the power transmitter antenna.The wireless power supply system according to claim 1 or 2, whereinthe measurement unit (341) is provided to the vehicle,the power receiver device is configured to transmit information on the measured background noise to the power transmitter device, andthe power-transmitter control unit is configured to, when the measured background noise is large based on the received information on the background noise, set the determination threshold to be larger than the determination threshold when the background noise is small.The wireless power supply system according to claim 5, whereinin the power receiver device, the measurement unit is configured to, when the power supply request signal is not supplied to the power-receiver communication antenna, measure the background noise.The wireless power supply system according to claim 6, whereinthe receiver control unit is configured to execute a process to temporarily stop supply of the power supply request signal to the power-receiver communication antenna, andthe measurement unit is configured to measure the background noise in a period in which supply of the power supply request signal to the power-receiver communication antenna is temporarily stopped.The wireless power supply system according to claim 1 or 2, whereinthe power receiver device is provided to the vehicle,the wireless power supply system further comprising:a processing unit (71) configured to associate the background noise measured by the measurement unit with a measurement location and a measurement time band and transmit the the associated background noise to the power receiver device of the vehicle, whereinthe power-receiver control unit of the power receiver device that has received information on the background noise associated with the measurement location and the measurement time band is configured to, when the vehicle equipped with the power-receiver control unit travels the measurement location included in the received information in the measurement time band included in the received information, set the intensity of the power supply request signal to be supplied to the power-receiver communication antenna using the background noise included in the received information.The wireless power supply system according to claim 1 or 2, whereinthe power receiver device is provided to the vehicle,the wireless power supply system further comprising:a prevention unit (401) configured to transmit a transmission prevention command of the power supply request signal in a specific location and in a specific time band to the power receiver device of the vehicle, whereinthe power-receiver control unit of the power receiver device that has received the transmission prevention command is configured to, when the vehicle equipped with the power-receiver control unit travels the specific location in the specific time band, stop supply of the power supply request signal to the power-receiver communication antenna, andthe measurement unit that is present in the specific location is configured to measure the background noise in the specific time band.A power transmitter device to be applied to a wireless power supply system, the wireless power supply system including a ground-side device and a vehicle-side device, one of the ground-side device and the vehicle-side device being the power transmitter device (20) including a power transmitter antenna (22), the other of the ground-side device and the vehicle-side device being a power receiver device (100) including a power receiver antenna (102), the power receiver device being configured to transmit a power supply request signal for power supply request to the power transmitter device, the power transmitter device being configured to energize the power transmitter antenna to perform wireless power supply to the power receiver antenna on condition that an intensity of the power supply request signal received by the power transmitter device exceeds a determination threshold,the power transmitter device comprising:a power-transmitter communication antenna (40) configured to receive the power supply request signal wirelessly transmitted from a power-receiver communication antenna (170) of the power receiver device;a measurement unit (91) configured to measure background noise near the power transmitter antenna; anda power-transmitter control unit (70), whereinthe power-transmitter control unit is configured to, when the measured background noise is large, set the determination threshold to be larger than the determination threshold when the background noise is small.A program for a power transmitter device to be applied to a wireless power supply system, the wireless power supply system including:a ground-side device and a vehicle-side device, one of the ground-side device and the vehicle-side device being the power transmitter device (20) including a power transmitter antenna (22), the other of the ground-side device and the vehicle-side device being a power receiver device (100) including a power receiver antenna (102), the power receiver device being configured to transmit a power supply request signal for power supply request to the power transmitter device, the power transmitter device being configured to energize the power transmitter antenna to perform wireless power supply to the power receiver antenna on condition that an intensity of the power supply request signal received by the power transmitter device exceeds a determination threshold, the power transmitter device including a power-transmitter communication antenna (40) configured to receive the power supply request signal wirelessly transmitted from a power-receiver communication antenna (170) of the power receiver device, a measurement unit (91) configured to measure background noise near the power transmitter antenna, and a power-transmitter control unit (70),the program configured to carry out:causing the power-transmitter control unit to set, when the measured background noise is large, the determination threshold to be larger than the determination threshold when the background noise is small.A control method for a power transmitter device to be applied to a wireless power supply system, the wireless power supply system including:a ground-side device and a vehicle-side device, one of the ground-side device and the vehicle-side device being the power transmitter device (20) including a power transmitter antenna (22), the other of the ground-side device and the vehicle-side device being a power receiver device (100) including a power receiver antenna (102), the power receiver device being configured to transmit a power supply request signal for power supply request to the power transmitter device, the power transmitter device being configured to energize the power transmitter antenna to perform wireless power supply to the power receiver antenna on condition that an intensity of the power supply request signal received by the power transmitter device exceeds a determination threshold, the power transmitter device including a power-transmitter communication antenna (40) configured to receive the power supply request signal wirelessly transmitted from a power-receiver communication antenna (170) of the power receiver device, a power-transmitter control unit (70), and a measurement unit (91) configured to measure background noise near the power transmitter antenna,the control method comprising:causing the power-transmitter control unit to execute a process to set, when the measured background noise is large, the determination threshold to be larger than the determination threshold when the background noise is small.A power receiver device to be applied to a wireless power supply system, the wireless power supply system including:a ground-side device and a vehicle-side device, one of the ground-side device and the vehicle-side device being a power transmitter device (20) including a power transmitter antenna (22), the other of the ground-side device and the vehicle-side device being the power receiver device (100) including a power receiver antenna (102), the power receiver device being configured to transmit a power supply request signal for power supply request to the power transmitter device, the power transmitter device being configured to energize the power transmitter antenna to perform wireless power supply to the power receiver antenna on condition that an intensity of the power supply request signal received by the power transmitter device exceeds a determination threshold; anda measurement unit (91, 341) configured to measure background noise near at least one of the power transmitter antenna and the power receiver antenna,the power receiver device comprising:the power receiver antenna;a power-receiver communication antenna (170) configured to transmit the power supply request signal wirelessly to a power-transmitter communication antenna (40) of the power transmitter device; anda power-receiver control unit (230) configured tocontrol energization of the power-receiver communication antenna to supply the power supply request signal to the power-receiver communication antenna, andset, when the measured background noise is large, the intensity of the power supply request signal supplied to the power-receiver communication antenna to be larger than the intensity when the measured background noise is small.A program for a power receiver device to be applied to a wireless power supply system, the wireless power supply system including:a ground-side device and a vehicle-side device, one of the ground-side device and the vehicle-side device being a power transmitter device (20) including a power transmitter antenna (22), the other of the ground-side device and the vehicle-side device being the power receiver device (100) including a power receiver antenna (102), the power receiver device being configured to transmit a power supply request signal for power supply request to the power transmitter device, the power transmitter device being configured to energize the power transmitter antenna to perform wireless power supply to the power receiver antenna on condition that an intensity of the power supply request signal received by the power transmitter device exceeds a determination threshold, the power receiver device including a power-receiver communication antenna (170) configured to transmit the power supply request signal wirelessly to a power-transmitter communication antenna (40) of the power transmitter device, and a power-receiver control unit (230) configured to control energization of the power-receiver communication antenna to supply the power supply request signal to the power-receiver communication antenna; anda measurement unit (91, 341) configured to measure background noise near at least one of the power transmitter antenna and the power receiver antenna,the program configured to carry out:causing the power-receiver control unit to execute a process to set, when the measured background noise is large, the intensity of the power supply request signal supplied to the power-receiver communication antenna to be larger than the intensity when the measured background noise is small.A control method for a power receiver device to be applied to a wireless power supply system, the wireless power supply system including:a ground-side device and a vehicle-side device, one of the ground-side device and the vehicle-side device being a power transmitter device (20) including a power transmitter antenna (22), the other of the ground-side device and the vehicle-side device being the power receiver device (100) including a power receiver antenna (102), the power receiver device being configured to transmit a power supply request signal for power supply request to the power transmitter device, the power transmitter device being configured to energize the power transmitter antenna to perform wireless power supply to the power receiver antenna on condition that an intensity of the power supply request signal received by the power transmitter device exceeds a determination threshold, the power receiver device including a power-receiver communication antenna (170) configured to transmit the power supply request signal wirelessly to a power-transmitter communication antenna (40) of the power transmitter device, and a power-receiver control unit (230) configured to control energization of the power-receiver communication antenna to supply the power supply request signal to the power-receiver communication antenna; anda measurement unit (91, 341) configured to measure background noise near at least one of the power transmitter antenna and the power receiver antenna,the control method comprising:causing the power-receiver control unit to execute a process to set, when the measured background noise is large, the intensity of the power supply request signal supplied to the power-receiver communication antenna to be larger than the intensity when the measured background noise is small.

Images