Wireless power transmission system and control device for supply device

Abstract

To provide a wireless power transmission system and a controller for a supply device which can suppress generation of a magnetic connection between a power supply unit and a power reception unit.SOLUTION: The present invention relates to a wireless power transmission system for performing wireless sending or receiving of power by a magnetic connection between a supply device on the ground side and a vehicle which is travelling, and the wireless power transmission system has a controller for controlling a wireless power transmission from a power transmission unit of a supply device to a power reception unit of a vehicle. The controller determines that a displacement is happening in a magnetic connection if the power reception unit keeps receiving power smaller than a target value by at least a predetermined value for a predetermined length of time during a wireless power transmission from the supply device to the vehicle, and in that case, moves the state of Magnetic Coupling Check and confirms the connection coefficient of the magnetic connection.SELECTED DRAWING: Figure 9

Description

[Technical Field]

[0001] The present invention relates to a wireless power transmission system and a control device for a power supply device. [Background technology]

[0002] Patent Document 1 discloses a wireless power transmission system that transmits power contactlessly from a power transmitting device on the ground to a power receiving device on the vehicle. In the configuration described in Patent Document 1, an abnormality in the power transmitting device is detected based on the output voltage and output current output from the power supply circuit of the power transmitting device and the phase difference between the output voltage and output current. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-115833 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the configuration described in Patent Document 1, if a misalignment occurs in the magnetic coupling between the power transmitting unit of the power transmitting device and the power receiving unit of the power receiving device, various parts may overheat or magnetic field leakage may occur due to misalignment.

[0005] The present invention has been made in consideration of the above circumstances, and aims to provide a wireless power transmission system and a control device for a supply device that can suppress deviations in magnetic coupling between a power transmitting unit and a power receiving unit. [Means for solving the problem]

[0006] The wireless power transmission system of the present invention is a wireless power transmission system that transmits wireless power via magnetic coupling between a supply device on the ground and a moving vehicle, and includes a control device that controls wireless power transmission from a power transmitting unit of the supply device to a power receiving unit of the vehicle, and is characterized in that the control device determines that a coupling error has occurred in the magnetic coupling when a state in which the received power at the power receiving unit is smaller than a target value by a predetermined value or more continues for a predetermined time during wireless power transmission from the supply device to the vehicle, and if it determines that a coupling error has occurred, transitions the state to Magnetic Coupling Check to check the coupling coefficient of the magnetic coupling.

[0007] According to this configuration, if it is determined that a coupling error has occurred in the magnetic coupling between the power transmitting unit and the power receiving unit during wireless power transmission from the supply device to the vehicle, the state transitions to Magnetic Coupling Check, and the coupling coefficient of the magnetic coupling is checked, thereby preventing the magnetic coupling between the power transmitting unit and the power receiving unit from being misaligned.

[0008] Furthermore, the control device may transition the state to Pairing if the coupling coefficient does not increase within a predetermined time in the Magnetic Coupling Check state.

[0009] With this configuration, the magnetic coupling coefficient is checked in the Magnetic Coupling Check, and if the coupling coefficient does not increase, the state transitions from the Magnetic Coupling Check to the Pairing state, which makes it possible to prevent the magnetic coupling between the power transmitting unit and the power receiving unit from becoming misaligned.

[0010] The control device of a supply device according to the present invention is a control device for a supply device that performs wireless power transmission via magnetic coupling with a moving vehicle, and includes a control unit that controls wireless power transmission from a power transmitting unit of the supply device to a power receiving unit of the vehicle, and the control unit determines that a coupling error has occurred in the magnetic coupling when it is determined that a state in which the received power at the power receiving unit is smaller than a target value by a predetermined value or more has continued for a predetermined time during wireless power transmission from the supply device to the vehicle, and if it is determined that a coupling error has occurred, it transitions the state to Magnetic Coupling Check to check the coupling coefficient of the magnetic coupling.

[0011] According to this configuration, if it is determined that a coupling error has occurred in the magnetic coupling between the power transmitting unit and the power receiving unit during wireless power transmission from the supply device to the vehicle, the state transitions to Magnetic Coupling Check, and the coupling coefficient of the magnetic coupling is checked, thereby preventing the magnetic coupling between the power transmitting unit and the power receiving unit from being misaligned.

[0012] Furthermore, when the coupling coefficient does not increase within a predetermined time in the Magnetic Coupling Check state, the control unit may transition the state to Pairing.

[0013] With this configuration, the magnetic coupling coefficient is checked in the Magnetic Coupling Check, and if the coupling coefficient does not increase, the state transitions from the Magnetic Coupling Check to the Pairing state, which makes it possible to prevent the magnetic coupling between the power transmitting unit and the power receiving unit from becoming misaligned. [Effects of the Invention]

[0014] In the present invention, when it is determined that a coupling error has occurred in the magnetic coupling between the power transmitting unit and the power receiving unit during wireless power transmission from the supply device to the vehicle, the state transitions to Magnetic Coupling Check, and the coupling coefficient of the magnetic coupling is checked, thereby preventing the magnetic coupling between the power transmitting unit and the power receiving unit from being misaligned. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 1 is a schematic diagram showing a wireless power transmission system according to an embodiment. [Figure 2] FIG. 2 is a diagram showing the overall configuration of a wireless power transmission system. [Figure 3] FIG. 3 is a schematic diagram for explaining wide-area wireless communication in a wireless power transmission system. [Figure 4] FIG. 4 is a block diagram illustrating the functional configuration of the power transmission ECU. [Figure 5] FIG. 5 is a block diagram illustrating the functional configuration of the vehicle ECU. [Figure 6] FIG. 6 is a diagram for explaining the power transmission process. [Figure 7] FIG. 7 is a sequence diagram showing a case where communication is performed between a vehicle and a supply device using wide-area wireless communication. [Figure 8] FIG. 8 is a sequence diagram showing the operation after the power supply from the supply device to the vehicle during travel is completed. [Figure 9] FIG. 9 is a diagram illustrating an example of a power transfer process. [Figure 10] FIG. 10 is a flowchart showing control during power transmission. [Figure 11] FIG. 11 is a flowchart showing the control during the magnetic coupling check. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, a wireless power transmission system and a control device for a power supply device according to an embodiment of the present invention will be specifically described, although the present invention is not limited to the embodiment described below.

[0017] 1 is a schematic diagram showing a wireless power transfer system according to an embodiment. The wireless power transfer system 1 includes a supply facility 2 and a vehicle 3. The supply facility 2 is a facility that supplies power to the traveling vehicle 3 in a contactless manner. The vehicle 3 is an electrically powered vehicle that can be charged with power supplied from an external power source, such as a battery electric vehicle (BEV) or a plug-in hybrid vehicle (PHEV).

[0018] This wireless power transmission system 1 transmits wireless power from a supply facility 2 to a vehicle 3 by magnetic field resonant coupling (magnetic resonance). The wireless power transmission system 1 transmits power contactlessly from the supply facility 2 to the vehicle 3 traveling on a road 4. In other words, the wireless power transmission system 1 transmits power by a magnetic field resonant method, and realizes power supply to the vehicle 3 while it is traveling by using magnetic field resonant coupling (magnetic field resonance). The wireless power transmission system 1 can be expressed as a dynamic wireless power transmission (D-WPT) system or a magnetic field dynamic wireless power transmission (MF-D-WPT) system.

[0019] The supply facility 2 includes a supply device 5 and an AC power source 6 that supplies power to the supply device 5. The supply device 5 contactlessly transmits the power supplied from the AC power source 6 to the vehicle 3. The AC power source 6 is, for example, a commercial power source. The supply device 5 includes a power transmission device 10 having a primary coil 11.

[0020] The supply device 5 includes a segment 7 including a primary coil 11 and a management device 8 that manages the segment 7. The segment 7 is embedded in a lane of the road 4. The management device 8 is installed beside the road 4. The segment 7 is electrically connected to the management device 8. The management device 8 is electrically connected to an AC power source 6 and supplies power from the AC power source 6 to the segment 7. The segment 7 is electrically connected to the AC power source 6 via the management device 8. A plurality of segments 7 can be arranged along the lane of the road 4. For example, as shown in FIG. 1 , the supply device 5 includes three segments 7 installed side by side along the lane of the road 4 and one management device 8 to which the three segments 7 are connected. The segment 7 has the function of contactlessly transmitting power from the supply device 5 to the vehicle 3. The management device 8 has the function of controlling wireless power transmission in the segment 7.

[0021] The vehicle 3 is equipped with a power receiving device 20 having a secondary coil 21. The power receiving device 20 is provided on the bottom of the body of the vehicle 3. When the vehicle 3 travels on a road 4 on which a primary coil 11 is installed, the primary coil 11 on the ground side and the secondary coil 21 on the vehicle side face each other in the vertical direction. The wireless power transmission system 1 transmits power contactlessly from the primary coil 11 of the power transmitting device 10 to the secondary coil 21 of the power receiving device 20 while the vehicle 3 is traveling on the road 4.

[0022] In this explanation, "driving" refers to a state in which the vehicle 3 is positioned on the road 4 in order to drive. "Driving" also includes a state in which the vehicle 3 is temporarily stopped on the road 4. For example, a state in which the vehicle 3 is stopped on the road 4 while waiting at a traffic light is also included in "driving." On the other hand, even if the vehicle 3 is positioned on the road 4, for example, if the vehicle 3 is parked or stopped, it is not included in "driving."

[0023] In this description, a lane in which the primary coil 11 (segments 7) is embedded may be referred to as a D-WPT lane, and a section of the road 4 where wireless power transmission by the supply device 5 is possible may be referred to as a D-WPT charging site. In the D-WPT lane and the D-WPT charging site, multiple primary coils 11 (multiple segments 7) are installed side by side in the direction of travel of the vehicle 3 over a predetermined section of the road 4.

[0024] 2 is a diagram showing the overall configuration of a wireless power transmission system. In a power supply facility 2, a power supply device 5 is electrically connected to an AC power source 6. In the power supply device 5, a segment 7 is electrically connected to a management device 8.

[0025] The supplying device 5 includes a configuration provided in the management device 8 and a configuration provided in the segment 7. The supplying device 5 includes a power transmitting device 10, a power transmitting ECU (Electronic Control Unit) 110, a first communication device 120, a second communication device 130, and a foreign object detection device 140.

[0026] The power transmitting device 10 includes an electric circuit connected to an AC power supply 6. The power transmitting device 10 includes a PFC (Power Factor Correction) circuit 210, an inverter (INV) 220, a filter circuit 230, and a power transmitting side resonant circuit 240.

[0027] The PFC circuit 210 improves the power factor of AC power input from the AC power supply 6, converts the AC power into DC power, and outputs it to the inverter 220. The PFC circuit 210 includes an AC / DC converter. The PFC circuit 210 is electrically connected to the AC power supply 6.

[0028] The inverter 220 converts the DC power input from the PFC circuit 210 into AC power. Each switching element of the inverter 220 is configured by an IGBT (Insulated Gate Bipolar Transistor), a MOSFET (Metal-Oxide-Semiconductor Field Effect Transistor), or the like, and performs switching operations in response to control signals from the power transmission ECU 110. For example, the drive frequency of the inverter 220 is 85 kHz. The inverter 220 outputs the converted AC power to the filter circuit 230.

[0029] The filter circuit 230 removes noise contained in the AC current input from the inverter 220 and supplies the AC power from which the noise has been removed to the power transmitting side resonant circuit 240. The filter circuit 230 is an LC filter that combines a coil and a capacitor. For example, the filter circuit 230 is configured as a T-type filter in which two coils and one capacitor are arranged in a T shape. The PFC circuit 210, the inverter 220, and the filter circuit 230 configure the power conversion unit 12 of the power transmitting device 10.

[0030] The power transmitting side resonant circuit 240 is a power transmitting unit that contactlessly transmits the AC power supplied from the filter circuit 230 to the power receiving device 20. When AC power is supplied from the filter circuit 230 to the power transmitting side resonant circuit 240, a current flows in the primary coil 11, generating a magnetic field for power transmission.

[0031] The power transmitting side resonant circuit 240 includes a primary coil 11 and a resonant capacitor. The primary coil 11 is a power transmitting coil. The resonant capacitor is connected in series to one end of the primary coil 11 and adjusts the resonant frequency of the power transmitting side resonant circuit 240. This resonant frequency is 10 kHz to 100 GHz, and preferably 85 kHz. For example, the power transmitting device 10 is configured so that the resonant frequency of the power transmitting side resonant circuit 240 matches the drive frequency of the inverter 220. The power transmitting side resonant circuit 240 constitutes the primary device 13 of the power transmitting device 10.

[0032] The power transmission device 10 includes a power conversion unit 12 and a primary device 13. The power conversion unit 12 includes a PFC circuit 210, an inverter 220, and a filter circuit 230. The primary device 13 includes a power transmission side resonant circuit 240. The power transmission device 10 has a configuration in which the power conversion unit 12 is provided in the management device 8, and the primary device 13 is provided in the segment 7.

[0033] In the supply device 5, the power conversion unit 12 of the power transmission device 10, the power transmission ECU 110, and the first communication device 120 are provided in the management device 8, and the primary device 13 of the power transmission device 10, the second communication device 130, and the foreign object detection device 140 are provided in the segment 7.

[0034] The power transmission ECU 110 is an electronic control device that controls the supply device 5. The power transmission ECU 110 includes a processor and a memory. The processor includes a central processing unit (CPU), a digital signal processor (DSP), a field-programmable gate array (FPGA), etc. The memory is a main storage device and includes a random access memory (RAM) and a read-only memory (ROM). The power transmission ECU 110 loads a program stored in the storage unit into a working area of ​​the memory (main storage device) and executes it. The power transmission ECU 110 controls each component through the execution of the program, thereby achieving functions that meet a predetermined purpose. The storage unit includes recording media such as an erasable programmable read-only memory (EPROM), a hard disk drive (HDD), and removable media. Examples of removable media include disc recording media such as a universal serial bus (USB) memory, a compact disc (CD), a digital versatile disc (DVD), and a Blu-ray disc (BD). The storage unit can store an operating system (OS), various programs, various tables, various databases, etc. Signals from various sensors are input to the power transmitter ECU 110. A signal from the foreign object detection device 140 is input to the power transmitter ECU 110. The power transmitter ECU 110 then executes various controls based on the signals input from the various sensors.

[0035] For example, the power transmitter ECU 110 executes power control to adjust the power to be transmitted. In the power control, the power transmitter ECU 110 controls the power transmitting device 10. The power transmitter ECU 110 outputs a control signal to the power conversion unit 12 to control the power supplied from the power conversion unit 12 to the primary device 13. The power transmitter ECU 110 controls the switching elements included in the PFC circuit 210 to adjust the power to be transmitted, and also controls the switching elements included in the inverter 220 to adjust the power to be transmitted.

[0036] Furthermore, the power transmitter ECU 110 executes communication control to control communication with the vehicle 3. In the communication control, the power transmitter ECU 110 controls the first communication device 120 and the second communication device 130.

[0037] The first communication device 120 is a ground-side communication device that performs wide-area wireless communication. The first communication device 120 performs wireless communication with a vehicle 3 that is traveling on a road 4 and is about to approach a WPT lane. The state before approaching a WPT lane refers to a state in which the vehicle 3 is in a position where it cannot perform short-range wireless communication with the supply device 5.

[0038] Wide-area wireless communication is communication with a communication distance of 10 meters to 10 kilometers. Wide-area wireless communication is communication with a longer communication distance than short-range wireless communication. Various wireless communication methods with long communication distances can be used for wide-area wireless communication. For example, communication compliant with communication standards such as 4G, LTE, 5G, and WiMAX established by 3GPP (registered trademark) and IEEE is used for wide-area wireless communication. In the wireless power transmission system 1, vehicle information linked to vehicle identification information (vehicle ID) is transmitted from the vehicle 3 to the supply device 5 using wide-area wireless communication.

[0039] The second communication device 130 is a ground-side communication device that performs short-range wireless communication. The second communication device 130 performs wireless communication with a vehicle 3 that is approaching or has entered a WPT lane among vehicles 3 traveling on a road 4. The state of approaching a WPT lane means that the vehicle 3 is in a position where it can perform short-range wireless communication with the supply device 5.

[0040] Short-range wireless communication is communication with a communication distance of less than 10 meters. Short-range wireless communication is communication with a shorter communication distance than wide-area wireless communication. As short-range wireless communication, various short-distance wireless communication methods with short communication distances can be used. For example, communication compliant with any communication standard established by IEEE, ISO, IEC, etc. is used for short-range wireless communication. As examples, Wi-Fi (registered trademark), Bluetooth (registered trademark), ZigBee (registered trademark), etc. are used for short-range wireless communication. Alternatively, technologies for performing short-range wireless communication may include RFID (Radio Frequency Identification), DSRC (Dedicated Short Range Communication), etc. In the wireless power transmission system 1, vehicle identification information, etc. is transmitted from the vehicle 3 to the supply device 5 using short-range wireless communication.

[0041] The foreign object detection device 140 detects metallic foreign objects, living organisms, etc. present above the primary coil 11. The foreign object detection device 140 is configured, for example, with a sensor coil or an imaging device installed on the ground. The foreign object detection device 140 is intended to perform a foreign object detection function (FOD) and a living object protection function (LOP) in the wireless power transmission system 1.

[0042] In the power supply device 5, the power transmission device 10 is configured to be divided into segments 7 and a management device 8, and three segments 7 are connected to one management device 8. The power transmission device 10 is configured so that one inverter 220 supplies power to three power transmission-side resonant circuits 240. In the power supply device 5, signals from each segment 7 are input to the management device 8. Signals from the second communication device 130 and foreign object detection device 140 provided in the first segment are input to the power transmission ECU 110. Similarly, signals from the second communication device 130 and foreign object detection device 140 provided in the second segment are input to the power transmission ECU 110. Signals from the second communication device 130 and foreign object detection device 140 provided in the third segment are input to the power transmission ECU 110. The power transmission ECU 110 can grasp the status of each segment 7 based on the signals input from each segment 7.

[0043] The vehicle 3 includes a power receiving device 20, a charging relay 310, a battery 320, a vehicle ECU 330, a third communication device 340, a fourth communication device 350, and a GPS (Global Positioning System) receiver 360.

[0044] The power receiving device 20 supplies the power received from the power transmitting device 10 to the battery 320. The power receiving device 20 is electrically connected to the battery 320 via a charging relay 310. The power receiving device 20 includes a power receiving-side resonant circuit 410, a filter circuit 420, and a rectifier circuit 430.

[0045] The power receiving side resonant circuit 410 is a power receiving unit that receives power transmitted contactlessly from the power transmitting device 10. The power receiving side resonant circuit 410 includes a secondary coil 21 and a resonant capacitor. The secondary coil 21 is a power receiving coil that receives power transmitted contactlessly from the primary coil 11. The resonant capacitor is connected in series to one end of the secondary coil 21 and adjusts the resonant frequency of the power receiving side resonant circuit 410. The resonant frequency of the power receiving side resonant circuit 410 is set to match the resonant frequency of the power transmitting side resonant circuit 240.

[0046] The resonant frequency of the power receiving side resonant circuit 410 is the same as the resonant frequency of the power transmitting side resonant circuit 240. Therefore, when the power transmitting side resonant circuit 240 generates a magnetic field while the power receiving side resonant circuit 410 faces the power transmitting side resonant circuit 240, the vibration of the magnetic field is transmitted to the power receiving side resonant circuit 410. The primary coil 11 and the secondary coil 21 are in a resonant state. When an induced current flows in the secondary coil 21 due to electromagnetic induction, an induced electromotive force is generated in the power receiving side resonant circuit 410. In this way, the power receiving side resonant circuit 410 receives the power transmitted contactlessly from the power transmitting side resonant circuit 240. The power receiving side resonant circuit 410 then supplies the power received from the power transmitting side resonant circuit 240 to the filter circuit 420. The power receiving side resonant circuit 410 constitutes the secondary device 22 of the power receiving device 20.

[0047] The filter circuit 420 removes noise contained in the AC current input from the power receiving side resonant circuit 410, and outputs the AC power from which the noise has been removed to the rectifier circuit 430. The filter circuit 420 is an LC filter that combines a coil and a capacitor. For example, the filter circuit 420 is configured as a T-type filter in which two coils and one capacitor are arranged in a T shape.

[0048] The rectifier circuit 430 converts the AC power input from the filter circuit 420 into DC power and outputs it to the battery 320. The rectifier circuit 430 is configured, for example, as a full-bridge circuit in which four diodes are full-bridge connected as rectifier elements. A switching element is connected in parallel to each diode of the rectifier circuit 430. Each switching element of the rectifier circuit 430 is configured by an IGBT, and performs switching operation in response to a control signal from the vehicle ECU 330. The rectifier circuit 430 supplies the converted DC power to the battery 320. The filter circuit 420 and the rectifier circuit 430 configure the power conversion unit 23 of the power receiving device 20.

[0049] The power receiving device 20 includes a secondary device 22 and a power conversion unit 23. The secondary device 22 includes a power receiving side resonant circuit 410. The power conversion unit 23 includes a filter circuit 420 and a rectifier circuit 430.

[0050] Charging relay 310 is provided between rectifier circuit 430 and battery 320. The open / close state of charging relay 310 is controlled by vehicle ECU 330. When power transmission device 10 charges battery 320, charging relay 310 is controlled to a closed state. When charging relay 310 is in a closed state, rectifier circuit 430 and battery 320 are electrically connected to each other. When charging relay 310 is in an open state, rectifier circuit 430 and battery 320 are electrically disconnected from each other. For example, when charging relay 310 is in an open state, vehicle 3 does not request power supply.

[0051] The battery 320 is a rechargeable DC power supply, and is configured, for example, by a lithium-ion battery or a nickel-metal hydride battery. The battery 320 stores the power supplied from the power transmitting device 10 to the power receiving device 20. The battery 320 can also supply power to the traction motor of the vehicle 3. The battery 320 is electrically connected to the traction motor via a PCU (Power Control Unit). The PCU is a power conversion device that converts the DC power of the battery 320 into AC power and supplies it to the traction motor. Each switching element of the PCU is configured by an IGBT, and performs switching operation in response to control signals from the vehicle ECU 330.

[0052] The vehicle ECU 330 is an electronic control device that controls the vehicle 3. The vehicle ECU 330 has the same hardware configuration as the power transmission ECU 110. Signals from various sensors mounted on the vehicle 3 are input to the vehicle ECU 330. Furthermore, a positioning signal received by a GPS receiver 360 is input to the vehicle ECU 330. The vehicle ECU 330 can acquire current position information of the vehicle 3 from the GPS receiver 360. Then, the vehicle ECU 330 executes various controls based on the signals input from the various sensors.

[0053] For example, the vehicle ECU 330 performs contactless charging control, in which power is transmitted contactlessly from the primary coil 11 to the secondary coil 21 and the power received by the secondary coil 21 is stored in the battery 320. In the contactless charging control, the vehicle ECU 330 controls the rectifier circuit 430, the charging relay 310, the third communication device 340, and the fourth communication device 350. The contactless charging control includes power control for controlling charging power and communication control for controlling communication with the supply device 5. In the power control, the vehicle ECU 330 controls a switching element included in the rectifier circuit 430 to adjust the power (charging power) supplied from the power receiving device 20 to the battery 320. In the communication control, the vehicle ECU 330 controls the third communication device 340 and the fourth communication device 350.

[0054] The third communication device 340 is a vehicle-side communication device that performs wide-area wireless communication. The third communication device 340 performs wireless communication with the first communication device 120 of the supply device 5 before the vehicle 3 traveling on the road 4 approaches the WPT lane. The wide-area wireless communication is two-way wireless communication. The communication between the first communication device 120 and the third communication device 340 is performed by high-speed wireless communication.

[0055] The fourth communication device 350 is a vehicle-side communication device that performs short-range wireless communication. The fourth communication device 350 performs wireless communication with the second communication device 130 of the supply device 5 when the vehicle 3 is approaching or entering a WPT lane. The short-range wireless communication is unidirectional wireless signaling. The unidirectional wireless signaling is P2PS (Point to Point Signaling). P2PS is used to notify vehicle identification information from the vehicle 3 to the supply device 5 in each of the activities of pairing, alignment check, magnetic coupling check, power transmission execution, and power transmission termination. P2PS can also be used as a means for lateral alignment check. The lateral direction refers to the width direction of the lane, i.e., the width direction of the vehicle 3.

[0056] The GPS receiver 360 detects the current position of the vehicle 3 based on positioning information obtained from a plurality of positioning satellites. The current position information of the vehicle 3 detected by the GPS receiver 360 is transmitted to the vehicle ECU 330.

[0057] In the supply device 5, the filter circuit 230 may be included in the management device 8 instead of in the segment 7. That is, the filter circuit 230 may be installed at the side of the road 4. In this case, the power conversion unit 12 includes the PFC circuit 210, the inverter 220, and the filter circuit 230, and the primary device 13 includes the power transmitting side resonant circuit 240.

[0058] The filter circuit 230 may be provided for each primary coil 11 individually, or may be provided for a plurality of primary coils 11 collectively.

[0059] Furthermore, the filter circuit 230 is not limited to a T-type filter, and may be, for example, a band-pass filter in which a coil and a capacitor are connected in series. This also applies to the filter circuit 420 of the vehicle 3.

[0060] Furthermore, in the power transmission device 10, when the inverter 220 is connected to the multiple primary coils 11, a changeover switch for switching the primary coil 11 to be energized may be provided in each primary device 13. This changeover switch may be provided in the management device 8 at the side of the road 4, or may be provided near the primary coil 11.

[0061] Furthermore, the power transmitting side resonant circuit 240 is not limited to a configuration in which the primary coil 11 and the resonant capacitor are connected in series. The primary coil 11 and the resonant capacitor may be connected in parallel, or a combination of parallel and series may be used. In short, the power transmitting side resonant circuit 240 is only required to be configured so that the resonant frequency of the power transmitting side resonant circuit 240 matches the drive frequency of the inverter 220, and there are no particular limitations on the connection relationship of its components. The same applies to the power receiving side resonant circuit 410 of the vehicle 3.

[0062] Furthermore, the drive frequency of the inverter 220 is not limited to 85 kHz, but may be a frequency close to 85 kHz. In other words, the drive frequency of the inverter 220 may be in a predetermined frequency band including 85 kHz.

[0063] Furthermore, the power transmitting device 10 may have a configuration in which a plurality of inverters 220 are connected to the output side power line (DC power line) of the PFC circuit 210.

[0064] Furthermore, the foreign object detection device 140 is not limited to being provided on the ground side, but may also be provided on the vehicle 3 side. For example, if the foreign object detection device on the vehicle 3 side detects a foreign object or living organism present above the primary coil 11, it can be configured to stop requesting power supply until the vehicle 3 passes the primary coil 11.

[0065] Furthermore, in the wireless power transmission system 1, the information transmitted from the vehicle 3 to the power supply device 5 using short-range wireless communication includes, in addition to vehicle identification information, a power supply request, a power supply request value, etc. The power supply request is information indicating a request for power transmission from the primary coil 11. The power supply request value is a request value for the amount of power to be transmitted from the power supply device 5 to the vehicle 3. The vehicle ECU 330 can calculate the power supply request value based on the SOC of the battery 320.

[0066] Furthermore, the wireless power transmission system 1 is not limited to a method of feeding power from the ground to the vehicle 3, but can also realize a method of feeding power from the vehicle 3 to the ground. In this case, by replacing the rectifier circuit 430 with an inverter, rectification during power supply and power reception can be realized.

[0067] FIG. 3 is a schematic diagram for explaining wide-area wireless communication in a wireless power transmission system.

[0068] In the wireless power transmission system 1, the vehicle 3 can communicate with the server 30, and the supply device 5 can communicate with the server 30. The server 30 is connected to a network 40, and can communicate with a plurality of vehicles 3 and a plurality of supply devices 5 via the network 40. The network 40 is configured by a WAN (Wide Area Network), which is a public communication network such as the Internet, a telephone communication network for mobile phones, or the like.

[0069] The vehicle 3 connects to the network 40 by wide area wireless communication using the third communication device 340. The vehicle 3 transmits information to the server 30 and receives information from the server 30.

[0070] The supplying device 5 connects to the network 40 by wide-area wireless communication using the first communication device 120. The supplying device 5 transmits information to the server 30 and receives information from the server 30.

[0071] The server 30 processes information related to wireless power transmission between the vehicle 3 and the supply device 5. The server 30 includes a communication device and a control device. This control device has a hardware configuration similar to that of the power transmission ECU 110. The server 30 creates various lists related to wireless power transmission based on the information received from the vehicle 3 and the information received from the supply device 5. Then, the server 30 provides the necessary information related to wireless power transmission to the required vehicle 3 and supply device 5 at the required timing based on the various lists.

[0072] 4 is a block diagram showing the functional configuration of the power transmitting ECU 110. The power transmitting ECU 110 includes a first communication control unit 510, a second communication control unit 520, and a power transmitting control unit 530.

[0073] The first communication control unit 510 executes first communication control that controls the first communication device 120. The first communication control controls wide area wireless communication on the supplying device 5 side, and controls communication of the supplying device 5 using the first communication device 120. In other words, the first communication control controls communication of the management device 8 of the supplying device 5. The first communication control controls communication between the supplying device 5 and the network 40, and also controls communication between the supplying device 5 and the server 30 via the network 40. The first communication control unit 510 is a Supply Equipment Communication Controller (SECC).

[0074] The second communication control unit 520 executes second communication control to control the second communication device 130. The second communication control controls short-range wireless communication on the supplying device 5 side, and controls communication of the supplying device 5 using the second communication device 130. In other words, the second communication control controls communication of segment 7 of the supplying device 5. The second communication control controls communication between the supplying device 5 and the vehicle 3 as communication that does not go through the network 40. The second communication control unit 520 is a PDCC (Primary Device Communication Controller).

[0075] The power transmission control unit 530 executes power transmission control to control the power transmitting device 10. The power transmission control is to control the power for transmission, and controls the power conversion unit 12 of the power transmitting device 10. The power transmission control unit 530 executes power control to control the PFC circuit 210 and the inverter 220.

[0076] 5 is a block diagram showing the functional configuration of vehicle ECU 330. Vehicle ECU 330 includes third communication control unit 610, fourth communication control unit 620, and charging control unit 630.

[0077] The third communication control unit 610 executes third communication control that controls the third communication device 340. The third communication control controls wide area wireless communication on the vehicle 3 side, and controls communication of the vehicle 3 using the third communication device 340. The third communication control controls communication between the vehicle 3 and the network 40, and also controls communication between the vehicle 3 and the server 30 via the network 40. The third communication control unit 610 is an EVCC (EV Communication Controller).

[0078] The fourth communication control unit 620 executes fourth communication control that controls the fourth communication device 350. The fourth communication control controls short-range wireless communication on the vehicle 3 side, and controls communication of the vehicle 3 using the fourth communication device 350. The fourth communication control controls communication between the vehicle 3 and the supply device 5 as communication that does not go through the network 40. The fourth communication control unit 620 is an SDCC (Secondary Device Communication Controller).

[0079] The charging control unit 630 executes charging control to control the power receiving device 20 and the charging relay 310. The charging control includes power control to control the received power in the secondary device 22 and relay control to control the connection state between the secondary device 22 and the battery 320. The charging control unit 630 executes power control to control the rectifier circuit 430. The charging control unit 630 executes relay control to switch the open / closed state of the charging relay 310.

[0080] In the wireless power transmission system 1 configured as above, when wireless communication is established between the vehicle 3 and the supply device 5, wireless power transmission is performed from the supply device 5 to the vehicle 3. When the vehicle 3 and the supply device 5 are paired by wireless communication, power is transmitted contactlessly from the primary coil 11 on the ground side to the secondary coil 21 on the vehicle side. Then, in the vehicle 3, charging control is performed to supply the power received by the secondary coil 21 to the battery 320.

[0081] Next, the power transfer process (D-WPT process) will be described with reference to Fig. 6. The power transfer process is structured as a chain of multiple activities, and is a process derived from states and corresponding transitions.

[0082] Fig. 6 is a diagram for explaining the power transmission process. Fig. 6 shows basic activities for explaining the power transmission process. The thick arrows shown in Fig. 6 represent transition lines. The state of the wireless power transmission system 1 in the power transmission process is represented by the activities that make up the power transmission process.

[0083] The activities that make up the power transmission process include a power transmission service session (D-WPT service session A70) that is an activity in the stage where power transmission is performed, activities in the stage before power transmission, and activities in the stage after power transmission. The activities can be explained by dividing the actors that perform them depending on whether or not communication is performed between the supply device 5 and the vehicle 3. The activities are divided into those that represent the state of only the supply device 5 side without communication, those that represent the state of only the vehicle 3 side without communication, and those that represent the state of both the supply device 5 and the vehicle 3 with communication.

[0084] As shown in FIG. 6, the activities include a master power on state (Master power On) A10, preparation A20, waiting for a request from vehicle 3 (Waiting for D-WPT service request) A30, a master power on state (Master power On) A40, preparation A50, communication setup and D-WPT service request (Request D-WPT service) A60, a D-WPT service session (D-WPT service session) A70, and termination of the D-WPT service session (Terminate D-WPT service session) A80.

[0085] Preparation A20 is a preparation state of the supplying device 5. In preparation A20, the supplying device 5 starts up the circuit and checks safety without communicating with the vehicle 3. The supplying device 5 transitions to the preparation A20 state when the master power supply enters the on state A10. Then, if the supplying device 5 starts up the circuit and checks safety in preparation A20, the state transitions to waiting for a request from the vehicle 3 (Waiting for D-WPT service request) A30. On the other hand, if there is a problem with the supplying device 5, the supplying device 5 notifies the vehicle 3 by wide-area wireless communication of information indicating that the wireless power transmission system 1 cannot be used (unavailable notice). The first communication device 120 transmits the unavailable notice to the vehicle 3.

[0086] Preparation A50 is the preparation state of vehicle 3. In preparation A50, vehicle 3 starts the circuit and checks safety without communicating with supply device 5. Vehicle 3 transitions to the preparation A50 state when the master power supply enters the on state A40. Then, if vehicle 3 starts the circuit and checks safety in preparation A50, the state transitions to communication setup and D-WPT service request A60. On the other hand, if there is a problem with vehicle 3, vehicle 3 does not start wide-area wireless communication and does not perform the subsequent sequence in the D-WPT process.

[0087] The communication setup and D-WPT service request A60 is initiated by the vehicle ECU 330. In response to the communication setup and D-WPT service request A60, the vehicle ECU 330 initiates wide-area wireless communication. First, when the vehicle 3 transitions from preparation A50 to communication setup and D-WPT service request A60, the third communication device 340 transmits a D-WPT service request signal. The third communication device 340 wirelessly communicates with the first communication device 120 corresponding to the D-WPT lane into which the vehicle 3 is scheduled to enter or has entered. The first communication device 120 to communicate with is selected based on the relative positional relationship between the current position of the vehicle 3 and the position of the D-WPT lane. On the supply device 5 side, when the first communication device 120 receives a D-WPT service request signal while in a request waiting state A30 from the vehicle 3, the state transitions to communication setup and D-WPT service request A60. Various pieces of information between the wide-area wireless communication and P2PS communication are linked using vehicle identification information. The processing sequence for this communication setting and D-WPT service request A60 is shown in FIG.

[0088] FIG. 7 is a sequence diagram showing a case where communication is performed between a vehicle and a supply device using wide-area wireless communication. The vehicle 3 transmits vehicle information to the server 30 (step S11). In step S11, the third communication device 340 of the vehicle 3 transmits the vehicle information to the server 30. The vehicle information includes vehicle identification information, various parameters of the power receiving device 20, current location information of the vehicle 3, and requested power. The vehicle ECU 330 calculates the requested power based on the SOC (State Of Charge) of the battery 320. The calculated requested power becomes the requested power supply value. In step S11, the vehicle ECU 330 causes the third communication device 340 to transmit the vehicle information at predetermined time intervals. The predetermined time interval is set according to the distance from the current location of the vehicle 3 to the start point of the WPT lane. The shorter the distance from the vehicle 3 to the start point of the WPT lane, the shorter the interval of the predetermined time.

[0089] When the server 30 receives the vehicle information from the vehicle 3, it identifies the vehicle identification information of the vehicle 3 located within the vicinity area of ​​the supply device 5 based on the current location information of the vehicle 3 included in the vehicle information (step S12). In step S12, the server 30 identifies the vehicle 3 located within a predetermined vicinity area from the supply device 5 based on the current location information of the vehicle 3 and the location information of the supply device 5. The vicinity area is set to an area within 500 meters, for example.

[0090] When the server 30 identifies the vehicle identification information of the vehicle 3, it transmits the vehicle information to the supplying device 5 (step S13). In step S13, the transmitting device of the server 30 transmits the vehicle information to the supplying device 5.

[0091] When the supplying device 5 receives the vehicle information from the server 30, it registers or deletes the vehicle identification information in the identification information list (step S14). In step S14, the power transmitting ECU 110 registers or deletes the vehicle identification information in the identification information list so that the vehicle identification information linked to the vehicle information is registered in the identification information list without excess or deficiency.

[0092] After registering or deleting the vehicle identification information in the identification information list, the supplying device 5 transmits the vehicle identification information registered in the identification information list to the server 30 (step S15). In step S15, the first communication device 120 of the supplying device 5 transmits the vehicle identification information to the server 30.

[0093] Then, when the server 30 receives the vehicle identification information from the supplying device 5, it transmits a list registration notification to the vehicle 3 corresponding to the vehicle identification information registered in the identification information list (step S16). In step S16, the communication device of the server 30 transmits the list registration notification to the vehicle 3. The list registration notification is a notification indicating that the vehicle identification information has been registered in the identification information list, and includes the identification information of the supplying device 5 and the location information of the supplying device 5.

[0094] In this way, when the vehicle 3 starts wide-area wireless communication and both the supply device 5 and the vehicle 3 are in the state of communication setup and D-WPT service request A60, the communication setup via wide-area wireless communication is successful. With this successful communication setup, the state transitions to a D-WPT service session A70.

[0095] Returning to Figure 6, the D-WPT service session A70 transmits power contactlessly from the power transmitting resonant circuit 240 of the supplying device 5 to the power receiving resonant circuit 410 of the vehicle 3 when a communication connection is established between the supplying device 5 and the vehicle 3. The D-WPT service session A70 begins when communication is successfully set up and ends when communication ends. When communication ends in the state of the D-WPT service session A70, the state transitions to Terminate D-WPT service session A80.

[0096] At the end of the D-WPT service session A80, the vehicle 3 ends the wide-area wireless communication with the supplying device 5. The vehicle 3 and the supplying device 5 can receive a trigger to end the D-WPT service session A70. Then, the vehicle ECU 330 prevents the D-WPT from starting for the secondary device 22 and the vehicle 3 until the third communication device 340 receives the next notification (a request signal for the D-WPT service).

[0097] Here, detailed activities of the D-WPT service session A70 will be described.

[0098] The D-WPT service session A70 includes a compatibility check and service authentication A110, a fine positioning A120, a pairing and alignment check A130, a magnetic coupling check A140, a perform power transfer A150, a standby A160, and a power transfer terminated A170.

[0099] The compatibility check and service authentication A110 will now be described. After the communication setup is successful, the vehicle ECU 330 and the power transmission ECU 110 confirm that the primary device 13 and the secondary device 22 are compatible. The compatibility check is performed on the supply device 5 side based on information associated with the vehicle identification information acquired through communication. Check items include the minimum ground clearance of the secondary device 22, the shape type of the power receiving side resonant circuit 410, the circuit topology of the secondary device 22, the self-resonant frequency of the secondary device 22, the number of secondary coils 21, etc.

[0100] In the compatibility check and service authentication A110, first, the vehicle 3 transmits compatibility information of the power receiving device 20 from the third communication device 340 to the supplying device 5. The compatibility information of the power receiving device 20 is transmitted by wide-area wireless communication. The first communication device 120 of the supplying device 5 receives the compatibility information of the power receiving device 20 from the vehicle 3. Then, the first communication device 120 of the supplying device 5 transmits the compatibility information of the power transmitting device 10 to the vehicle 3. The compatibility information of the power transmitting device 10 is transmitted by wide-area wireless communication. The third communication device 340 of the vehicle 3 receives the compatibility information of the power transmitting device 10 from the supplying device 5. The compatibility information can be transmitted and received between the vehicle 3 and the supplying device 5 by wide-area wireless communication via the network 40 and the server 30.

[0101] The elements of the compatibility information that the vehicle 3 sends to the supply device 5 include vehicle identification information, WPT power classes, air gap classes, WPT operating frequencies, WPT frequency adjustment, WPT type, WPT circuit topology, fine positioning method, pairing method, alignment method, and information on whether or not the power adjustment function is available.

[0102] The elements of the compatibility information that the supply device 5 sends to the vehicle 3 include supply device identification information, WPT power class, gap class, WPT drive frequency, WPT frequency adjustment, WPT type, WPT circuit topology, detailed alignment method, pairing method, alignment method, and information on whether or not the power adjustment function is present.

[0103] The names of each element will be explained in detail. Note that each element of the compatibility information transmitted from the vehicle 3 to the supply device 5 will be explained, and explanations of compatibility information transmitted from the supply device 5 to the vehicle 3 that overlaps with the compatibility information transmitted from the vehicle 3 to the supply device 5 will be omitted.

[0104] The gap class is information indicating the gap class that the secondary device 22 can receive power. The WPT power class is information indicating the power class that the secondary device 22 can receive power. The WPT drive frequency is information indicating the frequency of the power received by the secondary device 22. The WPT frequency adjustment is information indicating whether the drive frequency can be adjusted. The WPT type is information indicating the shape type of the power receiving side resonant circuit 410, and indicates the coil shape of the secondary coil 21. Examples of WPT types include circular and solenoid. The WPT circuit topology is information indicating the connection structure between the secondary coil 21 and the resonant capacitor. The WTP circuit topology includes series and parallel. The detailed alignment method is information indicating the method for performing alignment. The pairing method is a method for performing pairing in which the vehicle 3 identifies the supply device 5. The alignment method indicates a method for confirming the relative positions of the secondary device 22 and the primary device 13 before starting power transmission.

[0105] Detailed alignment A120 will now be described. The vehicle 3 performs detailed alignment A120 prior to or in parallel with the pairing and alignment check A130. The vehicle ECU 330 starts detailed alignment A120 when it determines that the vehicle 3 has approached or entered an area (WPT lane) where the supply device 5 is installed.

[0106] Vehicle ECU 330 guides vehicle 3 to align primary device 13 and secondary device 22 within a range that establishes sufficient magnetic coupling for wireless power transfer.

[0107] The detailed alignment A120 is basically performed manually or automatically on the vehicle 3 side. The detailed alignment A120 can be linked with an ADAS (Automated Driving Assistance System).

[0108] The detailed alignment A120 activity may then continue based on the alignment information transmitted from the supply device 5 to the vehicle 3 via wide-area wireless communication until the vehicle 3 leaves the D-WPT charging site or the state changes to communication termination, which is the end of the D-WPT service session A80.

[0109] The pairing / alignment check A130 will now be described. Here, pairing and alignment check will be described separately.

[0110] Pairing: The P2PS interface, which provides short-range wireless communication, ensures that the primary device 13 and secondary device 22 are uniquely paired. The pairing process is as follows:

[0111] First, the vehicle ECU 330 recognizes that the vehicle 3 has approached or entered a D-WPT lane. For example, the vehicle ECU 330 has map information including the D-WPT lane, and compares the vehicle's position information obtained by the GPS receiver 360 to recognize the approach or entry based on the straight-line distance. The vehicle 3 transmits information about which D-WPT lane it has approached to the server 30 via wide-area wireless communication. In other words, the third communication device 340 notifies the cloud with a signal indicating that the vehicle 3 has approached one of the D-WPT lanes. Furthermore, when the vehicle ECU 330 recognizes that the vehicle 3 has approached or entered a D-WPT lane, the fourth communication device 350 begins transmitting modulated signals at regular intervals to pair the primary device 13 and the secondary device 22.

[0112] Furthermore, the supplying device 5 may recognize that the vehicle 3 is approaching or entering a D-WPT lane using information obtained from the server 30 via wide-area wireless communication. The server 30 assigns the vehicle identification information of the vehicle 3 approaching each D-WPT lane to the supplying device 5 corresponding to that lane. Since the supplying device 5 only needs to refer to the vehicle identification information narrowed down by the server 30, the authentication process can be completed in a short time. When the supplying device 5 recognizes that the vehicle 3 is approaching a D-WPT lane, the second communication device 130 enters standby mode. In standby mode, the supplying device 5 waits to receive a modulated signal from the fourth communication device 350 of the vehicle 3. This modulated signal includes the vehicle identification information.

[0113] When the second communication device 130 receives the modulated signal from the vehicle 3, the supplying device 5 compares the vehicle identification information received by the short-range wireless communication with the vehicle identification information in the identification information list obtained as a result of the wide-area wireless communication with multiple vehicles 3 approaching the D-WPT lane. Through this comparison, the supplying device 5 identifies the vehicle 3.

[0114] When the vehicle ECU 330 recognizes that the vehicle 3 is outside the D-WPT lane, it stops transmission of the modulated signal from the fourth communication device 350. The vehicle ECU 330 can determine whether or not the vehicle 3 has passed through the D-WPT lane based on the map information and the position information of the vehicle itself.

[0115] The supply device 5 stops waiting for a modulated signal from the fourth communication device 350 when it determines that the vehicle 3 is not traveling in a D-WPT lane or when it determines that the vehicle 3 is not approaching a D-WPT lane.

[0116] Pairing is performed for the primary device 13 until the vehicle 3 leaves the D-WPT charging site or the state changes to communication end. When pairing is complete, the state transitions to alignment check.

[0117] The alignment check is intended to verify that the lateral distance between the primary device 13 and the secondary device 22 is within an acceptable range. The alignment check is performed using short-range wireless communication (P2PS).

[0118] The alignment check continues to be performed based on P2PS until the vehicle 3 leaves the D-WPT charging site or the state changes to communication end. The result of the alignment check can be transmitted from the first communication device 120 to the third communication device 340 via wide-area wireless communication.

[0119] The magnetic coupling check A140 will now be described. In the magnetic coupling check A140, the supply device 5 checks the magnetic coupling state and verifies that the secondary device 22 is within an allowable range. When the magnetic coupling check A140 is completed, the state transitions to power transmission execution A150.

[0120] The execution of power transmission A150 will now be described. In this state, the power supply device 5 transmits power to the power receiving device 20. The power transmission device 10 and the power receiving device 20 must be capable of controlling the transmitted power (transmitted power and received power) to ensure the usefulness of MF-D-WPT and to protect the power receiving device 20 and the battery 320. Larger power transmission helps increase the travel distance of the power receiving device 20 without static wireless charging or conductive charging. However, the capacity of the battery 320 varies depending on the model of the vehicle 3, and the power demand for driving may fluctuate suddenly. One example of this sudden fluctuation is sudden regenerative braking. When regenerative braking is performed while traveling on a D-WPT lane, regenerative braking takes priority, so the received power from the power receiving device 20 is supplied to the battery 320 in addition to the regenerated power. In this case, the power receiving device 20 needs to adjust the transmitted power to protect the battery 320 from overcharging.

[0121] Despite the need for power control, no new communication is initiated between the power supplying device 5 and the power receiving device 20 in this state because the instability and latency of communication may impair response and accuracy in power control. Therefore, the power supplying device 5 and the power receiving device 20 transmit and control power based on the information known up to this state.

[0122] The supplying device 5 increases the transmitted power of the magnetic coupling check in response to a power request previously sent by the third communication device 340 using wide area wireless communication. The supplying device 5 keeps the current and voltage fluctuations within their limits and attempts to maximize the transmitted power during the transition.

[0123] The power receiving device 20 basically receives the transmitted power from the power transmitting device 10 without any control. However, the power receiving device 20 starts control when the transmitted power exceeds or is about to exceed a limit, such as the rated power of the battery 320, which fluctuates depending on the state of charge and the drive power demand of the vehicle 3. Furthermore, the power control in the vehicle ECU 330 must also address malfunctions in wide-area wireless communication. Such malfunctions can lead to a discrepancy between the power control target in the primary device 13 and the request from the third communication device 340, and sudden failures of the power receiving device 20 and the battery 320 during power transmission. The power receiving device 20 controls the transmitted power based on the power request rate notified by the first communication device 120.

[0124] The power requirements are determined based on compatibility check information such as the WPT circuit topology, geometry, ground clearance, and EMC (electromagnetic compatibility) of the vehicle 3 and primary device 13. The magnetic field varies depending on these specifications, and power must be transmitted within a range that satisfies EMC.

[0125] There is a possibility that the power control in the power transmission ECU 110 and the power receiving device 20 may interfere with each other. This may occur particularly when the supplying device 5 attempts to realize a power request greater than the latest power limit of the power receiving device 20 through wide-area wireless communication. An example of this is sudden regenerative control of the relatively small battery 320 in the vehicle 3. If possible, it is desirable that the supplying device 5 be able to detect a mismatch between the power control target and the limit and adjust the power transmission to resolve the mismatch.

[0126] If power transmission is interrupted for a short period while the secondary device 22 is still above the primary device 13, for example, when the foreign object detection device 140 detects a foreign object on the primary device 13, or when misalignment of the secondary device 22 reduces the magnetic coupling coefficient, the state transitions to Stand-by A160. Note that if the vehicle 3 is equipped with a foreign object detection device, the vehicle 3 may also detect foreign objects.

[0127] When the secondary device 22 passes over the primary device 13, the state transitions to end power transfer A170. In this case, the magnetic coupling between the two devices weakens, so less power is transferred. The supplying device 5 can detect this weakening of the magnetic coupling by monitoring the transmitted power, so it essentially decides to transition to end power transfer A170 and then begins reducing the voltage to stop the power transfer.

[0128] The standby A160 will now be described. In this state, if power transmission is interrupted for a short time for some reason, and once D-WPT is ready in both the vehicle 3 and the supply device 5, the state returns to the execution of power transmission A150. If there is a possibility that power transmission may be interrupted, the state becomes standby A160.

[0129] The power transmission termination A170 will now be described. In this state, the supplying device 5 reduces the transmitted power to zero and retains or uploads power transmission result data such as total transmitted power, power transmission efficiency, and fault history. Each data is tagged with vehicle identification information. Finally, the supplying device 5 deletes the vehicle identification information of the vehicle 3 that has passed through the D-WPT lane. This allows the supplying device 5 to prepare for subsequent pairing and power transmission to other vehicles. The processing sequence for the power transmission termination A170 is shown in Figure 8.

[0130] 8 is a sequence diagram showing the operation after power supply from the supply device to the vehicle during travel is completed. When power reception from the supply device 5 is completed at the power receiving device 20 of the vehicle 3 (step S21), the vehicle 3 transmits power reception end information to the server 30 (step S22). In step S22, the power reception end information is transmitted from the third communication device 340 of the vehicle 3. The power reception end information includes, as information related to power reception from the supply device 5, for example, vehicle identification information of the vehicle 3, the received power from the supply device 5, the power receiving efficiency, and an abnormality detection result.

[0131] When the process of step S21 is performed, the supplying device 5 ends the power transmission to the vehicle 3 (step S23). The process of step S21 and the process of step S23 may or may not be performed simultaneously. When the process of step S23 is performed, the supplying device 5 transmits power transmission end information to the server 30 (step S24). In step S24, the power transmission end information is transmitted from the first communication device 120 of the supplying device 5.

[0132] When the server 30 receives the power reception end information from the vehicle 3 and the power transmission end information from the supply device 5, the server 30 performs a power supply end process to end the power supply from the supply device 5 to the vehicle 3 (step S25). In the power supply end process, based on the power reception end information and the power transmission end information, a process of calculating the amount of power to be supplied from the supply device 5 to the vehicle 3 and a process of charging the user of the vehicle 3 based on the calculated amount of power to be supplied are performed.

[0133] Furthermore, the vehicle 3 transmits the vehicle information to the server 30 regardless of the power supply termination process (step S26). In step S26, the vehicle information is transmitted from the third communication device 340 of the vehicle 3.

[0134] When the server 30 receives the vehicle information from the vehicle 3 after performing the power supply end process, the server 30 identifies the vehicle identification information of the vehicle 3 located within the vicinity of each supply device 5 based on the vehicle information (step S27).

[0135] Then, if a power supply device 5 has already performed the power supply termination process for a certain vehicle 3, the server 30 deletes the vehicle identification information of the vehicle 3 for which the power supply termination process has already been performed from the vehicle identification information of the vehicles 3 within the vicinity of the supply device 5 identified in the process of step S27 (step S28).

[0136] Then, the server 30 transmits to each supply device 5 vehicle information linked to the vehicle identification information of the vehicle 3 identified as being located within the vicinity area of ​​each supply device 5 that has not been deleted in the processing of step S28 (step S29).

[0137] After the vehicle information is transmitted to each supplying device 5 in the process of step S29, when the supplying device 5 receives the vehicle information from the server 30, the supplying device 5 registers or deletes the vehicle identification information in the identification information list (step S30). The process of step S30 is the same as the process of step S14 in FIG. 7. Thereafter, the supplying device 5 transmits the vehicle identification information registered in the identification information list to the server 30 (step S31). The process of step S31 is the same as the process of step S15 in FIG. 7.

[0138] Then, when the server 30 receives the vehicle identification information from the supplying device 5, it transmits a list registration notification to the vehicle 3 corresponding to the vehicle identification information registered in the identification information list (step S32). The processing of step S32 is similar to the processing of step S16 in FIG. 7.

[0139] 8 is performed, the identification information list will contain the vehicle identification information of vehicles 3 that are located within the vicinity of each supply device 5, that have not terminated power supply from that supply device 5, and that have not received a request to delete the vehicle identification information. If the vehicle identification information of the vehicle 3 is registered in the identification information list of any supply device 5, the vehicle 3 will receive a list registration notification. Therefore, by receiving the list registration notification, the vehicle ECU 330 can determine that the vehicle is registered in any supply device 5. If the vehicle 3 moves out of the vicinity of the supply device 5, the vehicle identification information of the vehicle 3 will be deleted from the identification information list of the supply device 5.

[0140] Returning to FIG. 6 , at the end of power transfer A170, the power receiving device 20 does not need to take any action to zero the transmitted power. The P2PS interface remains active when the vehicle 3 is in the D-WPT lane, and the state of the power receiving device 20 automatically transitions to pairing for the next power transfer from the primary device 13. As shown in FIG. 6 , the state transitions from the end of power transfer A170 to the pairing and alignment check A130. As shown in FIG. 6 , when a predetermined transition condition is met, it is possible to transition from the magnetic coupling check A140 to the pairing and alignment check A130, or from the execution of power transfer A150 to the pairing and alignment check A130. Pairing may be performed individually for multiple primary coils 11, or may be performed at a representative point for multiple primary coils 11.

[0141] If there is no D-WPT request from the vehicle ECU 330, or if the series of states from the communication setup and D-WPT service request A60 to the power transmission termination A170 is prohibited, the D-WPT service session A70 transitions to the D-WPT service session termination A80, which terminates the wide-area wireless communication between the first communication device 120 and the third communication device 340. For example, D-WPT is terminated when the battery 320 is too charged or when the power receiving device 20 is too hot for continuous power transmission. Such unnecessary D-WPT can be disabled simply by deactivating the P2PS interface. However, by terminating the wide-area wireless communication, the power transmitting ECU 110 can free up memory occupied by the vehicle 3 without requiring D-WPT by terminating the established wide-area wireless communication.

[0142] Furthermore, the D-WPT service session A70 is not limited to the transitions indicated by the transition lines in FIG. 6 . When the activities following the pairing and alignment check A130 in the D-WPT service session A70 are completed, if a condition for the power transmission process to remain in the D-WPT service session A70 is met, the D-WPT service session does not transition to the end of the D-WPT service session A80 but transitions to the compatibility check and service authentication A110. For example, if a predetermined transition condition is met in the state of the magnetic coupling check A140, the state can transition to the compatibility check and service authentication A110. The transitions of each activity in the D-WPT service session A70 are controlled by a control device of the wireless power transmission system 1. The control device of the wireless power transmission system 1 includes a power transmitter ECU 110 and a vehicle ECU 330. The power transmitter ECU 110 functions as a control device for the power supply device 5. The vehicle ECU 330 functions as a control device for the power receiving device 20.

[0143] Fig. 9 is a diagram showing an example of a power transmission process. In a D-WPT service session A70 shown in Fig. 9, the pairing and alignment check A130 shown in Fig. 6 is subdivided into pairing A131 and alignment check A132.

[0144] In the D-WPT service session A70 shown in FIG. 9, once the compatibility check and service authentication A110 is completed, the state transitions to pairing A131. In pairing A131, the pairing state process described above is executed. Once pairing A131 is completed, the state transitions to alignment check A132. The alignment check A132 verifies that the lateral distance between the primary device 13 and the secondary device 22 is within an acceptable range. Once the alignment check A132 is completed, the state transitions to magnetic coupling check A140.

[0145] The magnetic coupling check A140 verifies that the coupling coefficient of the magnetic coupling between the power transmitting unit of the power transmitting device 10 and the power receiving unit of the power receiving device 20 is within an allowable value. Magnetic coupling is synonymous with magnetic resonance coupling (magnetic resonance). The magnetic coupling check A140 determines whether the coupling coefficient of the magnetic coupling is greater than a threshold value. If the coupling coefficient is greater than the threshold value, the magnetic coupling check A140 is completed. Then, when the magnetic coupling check A140 is completed, the state transitions to power transmission execution A150.

[0146] In addition, in the D-WPT service session A70, it is possible to transition from the state of power transmission execution A150 to the state of magnetic coupling check A140. Furthermore, it is also possible to transition from the state of magnetic coupling check A140 to the state of pairing A131.

[0147] Specifically, the control device of the wireless power transmission system 1 determines whether the received power is smaller than the requested value (target power) by a predetermined value or more during power transmission execution A150. If the control device determines that the received power at the power receiving device 20 is smaller than the requested value by a predetermined value or more, the control device determines that a coupling error has occurred in the magnetic coupling between the power receiving unit and the power transmitting unit. If the control device determines that a coupling error has occurred in the magnetic coupling during power transmission execution A150, the control device transitions the state to magnetic coupling check A140. Then, the control device checks the coupling coefficient of the magnetic coupling during the magnetic coupling check A140. At this time, if the coupling coefficient does not increase to a predetermined value within a predetermined time during the magnetic coupling check A140, the control device transitions the state to pairing A131. In this way, if the control device determines that a coupling error has occurred in the magnetic coupling between the power receiving unit and the power transmitting unit during power transmission execution A150, the control device can transition the state to magnetic coupling check A140. This makes it possible to prevent overheating of various components and magnetic field leakage due to magnetic coupling error.

[0148] 10 is a flowchart showing the control during power transmission. The control shown in FIG.

[0149] The control device determines whether or not wireless power is being transmitted from the supply device 5 to the vehicle 3 (step S101). In step S101, it is determined whether or not the state is power transmission execution A150. In step S101, the control device determines whether or not the state is power transmission execution A150.

[0150] If it is determined that power is not being transmitted from the supply device 5 to the vehicle 3 (step S101: No), this control routine ends.

[0151] If it is determined that power is being transmitted from the supply device 5 to the vehicle 3 (step S101: Yes), the control device determines whether a state in which the received power of the vehicle 3 is smaller than the target power by a predetermined value or more has continued for a predetermined time (step S102). In power transmission execution A150, the control device controls the transmitted power from the supply device 5 so that the received power at the power receiving unit becomes the target power. The target power is a required value of supplied power set by the vehicle ECU 330. The required value of supplied power is transmitted from the vehicle 3 to the supply device 5 by short-range wireless communication. The power transmitting ECU 110 controls the transmitted power to satisfy the target power. In step S102, the vehicle ECU 330 determines whether a state in which the received power at the power receiving device 20 is smaller than the target power by a predetermined value or more has continued for a predetermined time. The predetermined time is a time set in advance by the vehicle ECU 330.

[0152] If it is determined that the state in which the received power on the vehicle 3 side is smaller than the target power by a predetermined value or more has not continued for a predetermined time (step S102: No), this control routine ends. In this case, the state is maintained in power transmission execution A150.

[0153] If it is determined that the state in which the received power on the vehicle 3 side is smaller than the target power by a predetermined value or more has continued for a predetermined time (step S102: Yes), the control device transitions the state to magnetic coupling check A140 (step S103). In step S103, the state transitions from power transfer execution A150 to magnetic coupling check A140. In this case, the power transmitter ECU 110 ends power transfer from the power transmitter 10. When the processing of step S103 is performed, this control routine ends.

[0154] In step S102, power transmitter ECU 110 may determine whether the state in which the transmitted power of power transmitter 10 is smaller than the target power by a predetermined value or more has continued for a predetermined time. In this case, when it is determined that the state in which the transmitted power is smaller than the target power by a predetermined value or more has continued for a predetermined time, the control routine proceeds to step S103. When it is determined that the state in which the transmitted power is smaller than the target power by a predetermined value or more has not continued for a predetermined time, the control routine ends while maintaining the state of power transmission execution A150.

[0155] 11 is a flowchart showing the control during the magnetic coupling check. The control shown in FIG.

[0156] In magnetic coupling check A140, the control device determines whether the state in which the coupling coefficient is smaller than a predetermined value has continued for a predetermined time (step S201). In step S201, the power transmitter ECU 110 checks the coupling coefficient of the magnetic coupling between the power transmitting unit of the power transmitter 10 and the power receiving unit of the power receiving device 20. In this case, the power transmitter ECU 110 determines whether the coupling coefficient is larger than a threshold value. Furthermore, the power transmitter ECU 110 determines whether the state in which the coupling coefficient is smaller than the predetermined value has continued for a predetermined time. The predetermined value and the predetermined time are values ​​that are set in advance by the control device.

[0157] If it is determined that the state in which the coupling coefficient is smaller than the predetermined value has not continued for the predetermined time (step S201: No), this control routine ends. In this case, the state is maintained in the magnetic coupling check A140.

[0158] If it is determined that the state in which the coupling coefficient is smaller than the predetermined value has continued for a predetermined time (step S201: Yes), the control device transitions the state to pairing A131 (step S202). In step S202, the state transitions from magnetic coupling check A140 to pairing A131. After the processing of step S202 is performed, this control routine ends.

[0159] As described above, according to the embodiment, if it is determined that a magnetic coupling mismatch has occurred during power transmission execution A150, the state can be transitioned to magnetic coupling check A140. This makes it possible to suppress a magnetic coupling mismatch between the power transmitting unit of the power transmitting device 10 and the power receiving unit of the power receiving device 20. Furthermore, since it is possible to prevent power transmission from continuing while a magnetic coupling mismatch remains, it is possible to suppress overheating of various components and magnetic field leakage due to the mismatch. [Explanation of symbols]

[0160] 1. Wireless power transmission system 2 Supply equipment 3 vehicles 4 road 5 Feeding device 6 AC power supply 7 segments 8 Management device 10 Power transmission equipment 11 Primary coil 13 Primary device 20 Power receiving device 21 Secondary coil 22 Secondary device 110 Power Transmission ECU 330 Vehicle ECU 240 Power transmission side resonant circuit 410 Receiving side resonant circuit 530 Power transmission control unit

Claims

1. A wireless power transmission system that performs wireless power transmission by magnetic coupling between a ground-side supply device and a running vehicle, a control device that controls wireless power transmission from a power transmission unit of the power supply device to a power receiving unit of the vehicle; The control device determining that a coupling error has occurred in the magnetic coupling when a state in which the received power at the power receiving unit is smaller than a target value by a predetermined value or more continues for a predetermined time during wireless power transmission from the supply device to the vehicle; If it is determined that the coupling error has occurred, the state is transitioned to Magnetic Coupling Check, and the coupling coefficient of the magnetic coupling is checked. A wireless power transmission system.

2. The control device transitions the state to Pairing if the coupling coefficient does not increase within a predetermined time in the Magnetic Coupling Check state.

2. The wireless power transmission system according to claim 1 .

3. A control device for a power supply device that performs wireless power transmission by magnetic coupling with a running vehicle, a control unit that controls wireless power transmission from a power transmission unit of the power supply device to a power receiving unit of the vehicle; The control unit determining that a coupling error has occurred in the magnetic coupling when it is determined that a state in which the received power at the power receiving unit is smaller than a target value by a predetermined value or more has continued for a predetermined time during wireless power transmission from the supply device to the vehicle; If it is determined that the coupling error has occurred, the state is transitioned to Magnetic Coupling Check, and the coupling coefficient of the magnetic coupling is checked. A control device for a supply device.

4. The control unit transitions the state to Pairing when the coupling coefficient does not increase within a predetermined time in the Magnetic Coupling Check state.

4. The control device for a supply device according to claim 3.

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