Wireless Power Transfer System
The wireless power transmission system addresses the challenge of charging multiple devices on a vehicle by using a roadside supply device with a processor to manage power distribution, enabling efficient charging during travel.
Patent Information
- Application Number
- JP2023013397
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2023-01-31
- Publication Date
- 2026-03-04
- Estimated Expiration
- 2043-01-31
Smart Images

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Abstract
Description
[Technical Field]
[0001] The present disclosure relates to a wireless power transfer system. [Background technology]
[0002] Patent Document 1 describes a technology for a contactless charging system that includes a vehicle equipped with a power receiving device having a secondary coil and a contactless charger equipped with a primary coil, and charges the vehicle contactlessly. In this technology, when the contactless charger receives a signal indicating an abnormality in the power receiving device or detects a charging abnormality in the contactless charger, charging is temporarily stopped and then, after a predetermined time has passed, a procedure is taken to resume charging. [Prior art documents] [Patent documents]
[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-092978 Summary of the Invention [Problem to be solved by the invention]
[0004] However, Patent Document 1 only considers the case where one power receiving device is provided on the vehicle side, and does not consider the case where multiple power receiving devices are provided, so there is room for improvement.
[0005] The present disclosure has been made in view of the above, and aims to provide a wireless power transmission system that can charge even when a plurality of power receiving devices are provided on the vehicle side. [Means for solving the problem]
[0006] In order to solve the above-mentioned problems and achieve the objectives, the wireless power transmission system of the present disclosure is a power transmission system that contactlessly transmits power from a roadside supply device to a vehicle, the vehicle comprising a plurality of power receiving devices that receive power from the supply device, and a processor, the processor determining the power to be received by each of the plurality of power receiving devices, and transmitting power information regarding the power of each of the plurality of power receiving devices to the supply device. [Effects of the Invention]
[0007] According to the present disclosure, it is possible to achieve an effect of enabling charging even when a plurality of power receiving devices are provided on the vehicle side. [Brief explanation of the drawings]
[0008] [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 diagram showing the overall configuration of a wireless power transmission system. [Figure 4] FIG. 4 is a schematic diagram for explaining wide-area wireless communication in a wireless power transmission system. [Figure 5] FIG. 5 is a block diagram illustrating the functional configuration of the power transmission ECU. [Figure 6] FIG. 6 is a block diagram illustrating the functional configuration of the vehicle ECU. [Figure 7] FIG. 7 is a diagram for explaining the power transmission process. [Figure 8] FIG. 8 is a sequence diagram showing a case where communication is performed between a vehicle and a supply device using wide-area wireless communication. [Figure 9] FIG. 9 is a sequence diagram showing the operation after the power supply from the supply device to the vehicle during travel is completed. [Figure 10] FIG. 10 is a sequence diagram showing the operation using P2PS between the vehicle and the supply device when power transmission is performed. [Figure 11] FIG. 11 is a sequence diagram showing the operation using P2PS between a vehicle and a supply device when power transmission is performed. DETAILED DESCRIPTION OF THE INVENTION
[0009] Hereinafter, a wireless power transmission system according to an embodiment of the present invention will be specifically described, although the present invention is not limited to the embodiment described below.
[0010] [Configuration of wireless power transmission system] 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 large vehicle such as a plug-in hybrid electric vehicle (PHEV), a bus, or a truck.
[0011] 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.
[0012] [Configuration of supply device] 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.
[0013] 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 a function of contactlessly transmitting power from the supply device 5 to the vehicle 3. The management device 8 has a function of controlling wireless power transmission in the segment 7.
[0014] [Vehicle configuration] 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.
[0015] 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, "driving" also includes a state in which the vehicle 3 is stopped on the road 4 while waiting for a traffic light, etc. 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, this does not include "driving."
[0016] 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 in a row along the direction of travel of the vehicle 3 over a predetermined section of the road 4.
[0017] [Overall configuration of wireless power transmission system] 2 and 3 are diagrams showing the overall configuration of a wireless power transmission system. Note that the wireless power transmission systems 1 shown in FIGS. 2 and 3 have the same configuration of the supply facility 2, and only differ in partial configuration of the vehicles 3A and 3B. The following description will be given in the order of the supply facility 2, vehicle 3A, and vehicle 3B.
[0018] [Functional configuration of supply device] In the power supply facility 2, a power supply device 5 and an AC power source 6 are electrically connected. In the power supply device 5, a segment 7 and a management device 8 are electrically connected. The power supply device 5 includes a configuration provided in the management device 8 and a configuration provided in the segment 7. The power supply device 5 includes a power transmission device 10, a power transmission ECU (Electronic Control Unit) 110, a first communication device 120, a second communication device 130, and a foreign object detection device 140.
[0019] 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.
[0020] 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.
[0021] 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.
[0022] 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.
[0023] 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.
[0024] 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. The 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.
[0025] 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.
[0026] 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.
[0027] 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), and the like. 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 programs stored in the storage unit into a working area of the memory (main storage device) and executes them. The power transmission ECU 110 controls each component through the execution of the programs, 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 transmission ECU 110. A signal from the foreign object detection device 140 is input to the power transmission ECU 110. The power transmission ECU 110 then executes various controls based on the signals input from the various sensors.
[0028] 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.
[0029] Furthermore, the power transmitter ECU 110 executes communication control for controlling 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.
[0030] 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.
[0031] 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.
[0032] 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.
[0033] 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.
[0034] 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.
[0035] 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 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.
[0036] [Vehicle functional configuration] First, the functional configuration of the vehicle 3A will be described. As shown in FIG. 2, the vehicle 3A includes power receiving devices 201 to 20 n (n = integer equal to or greater than 2) and charging relay 3101 to charging relay 310 n (n=an integer equal to or greater than 2), a battery 320, a vehicle ECU 330, a third communication device 340, and fourth communication devices 3501 to 350. n (n=an integer equal to or greater than 2) and a GPS (Global Positioning System) receiver 360. n When referring to any one of the above, it is simply referred to as the power receiving device 20. Furthermore, the fourth communication device 3501 to the fourth communication device 350 n When referring to either one of the vehicles 3A and 3B, it will be simply referred to as the fourth communication device 350. When referring to either the vehicle 3A or the vehicle 3B, it will be simply referred to as the vehicle 3.
[0037] 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.
[0038] 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 is configured by a power receiving side resonant circuit including 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. This 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. 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.
[0039] 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. As a result, 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.
[0040] 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.
[0041] 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, by 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.
[0042] 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.
[0043] 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.
[0044] 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 power supplied from the power transmitting device 10 to the power receiving device 20. The battery 320 can also supply power to a 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 DC power from 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.
[0045] 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 performs various controls based on the signals input from the various sensors.
[0046] 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.
[0047] The vehicle ECU 330 also includes power receiving devices 201 to 202 that receive power from the supply device 5.n The vehicle ECU 330 determines the power of each of the power receiving devices 201 to 202 and transmits power information relating to the determined power to the power supply device 5. Furthermore, the vehicle ECU 330 n The corresponding fourth communication devices 3501 to 350 n 2, the power receiving device 201 to the power receiving device 20 n Each of the power receiving devices 201 to 202 transmits power information relating to the power received from the power supply device 5. Furthermore, the vehicle ECU 330 n The maximum value of the power received from the power supply device 5 and the power receiving devices 201 to 20 n The vehicle ECU 330 causes the third communication device 340 to transmit total power information relating to the total power obtained by adding up the maximum values of the power received by each of the power receiving devices 201 to 20. n If there is a faulty power receiving device 20 among them, the charging relay 310 corresponding to the faulty power receiving device 20 is opened (open state). In the embodiment, the vehicle ECU 330 functions as the processor.
[0048] 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.
[0049] 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 supplying device 5 when the vehicle 3 is approaching or entering a WPT lane. The short-range wireless communication is one-way wireless signaling. The one-way wireless signaling is P2PS (Point to Point Signaling). P2PS is used to notify the vehicle 3 of vehicle identification information to the supplying device 5 in each activity of pairing, alignment check, magnetic coupling check, end of power transmission, and end of power transmission. P2PS can also be used as a means for checking lateral alignment (alignment check). The lateral direction refers to the width direction of the lane, that is, the width direction of the vehicle 3. In the vehicle 3A, the fourth communication devices 3501 to 350 correspond to the power receiving devices 201 to 20n, respectively. n That is, the vehicle 3A is provided with a fourth communication device 350 equal to the number of power receiving devices 20. The vehicle 3A also has charging relays 3101 to 310 corresponding to the plurality of power receiving devices 201 to 20n, respectively. n is provided.
[0050] 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.
[0051] Next, the configuration of vehicle 3B will be described. As shown in FIG. 3, vehicle 3B has the same configuration as vehicle 3A, and includes power receiving devices 201 to 20 n (n = integer equal to or greater than 2) and charging relay 3101 to charging relay 310 n (n=an integer of 2 or more), a battery 320, a vehicle ECU 330, a third communication device 340, one fourth communication device 350, and a GPS (Global Positioning System) receiver 360. Therefore, detailed description of each component constituting the vehicle 3B will be omitted.
[0052] In addition, the filter circuit 230 of the supply device 5 may be included in the management device 8, not 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.
[0053] 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.
[0054] 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.
[0055] 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.
[0056] 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.
[0057] Furthermore, the drive frequency of the inverter 220 is not limited to 85 kHz, but may be any 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.
[0058] 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.
[0059] 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.
[0060] 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.
[0061] 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, the rectifier circuit 430 can be replaced with an inverter to realize rectification during power supply and power reception.
[0062] [Outline of wide-area wireless communication] FIG. 4 is a schematic diagram for explaining wide-area wireless communication in a wireless power transmission system.
[0063] In the wireless power transmission system 1, vehicles 3 (3A, 3B) can communicate with a server 30, and supply devices 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.
[0064] 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.
[0065] 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.
[0066] [Functional configuration of the power transmission ECU] 5 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.
[0067] 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).
[0068] 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).
[0069] 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 power 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.
[0070] [Vehicle ECU Functional Configuration] 6 is a block diagram showing the functional configuration of vehicle ECU 330. Vehicle ECU 330 includes a third communication control unit 610, a fourth communication control unit 620, and a charging control unit 630.
[0071] 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).
[0072] 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).
[0073] 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.
[0074] 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.
[0075] [Outline of the power transmission process] Next, the power transfer process (D-WPT process) will be described with reference to Fig. 7. The power transfer process is structured as a chain of multiple activities, and is a process derived from states and corresponding transitions.
[0076] Fig. 7 is a diagram for explaining the power transmission process. Fig. 7 shows basic activities for explaining the power transmission process. The thick arrows shown in Fig. 7 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.
[0077] 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. Furthermore, 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.
[0078] As shown in FIG. 7, 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.
[0079] 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 of the power transmission process 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.
[0080] Preparation A50 is the preparation state of the vehicle 3. In preparation A50, the vehicle 3 starts up the circuit and checks safety without communicating with the supply device 5. The vehicle 3 transitions to the preparation A50 state when the master power supply enters the on state A40. Then, if the vehicle 3 starts up the circuit and checks safety in preparation A50, the state of the power transmission process transitions to communication setup and D-WPT service request A60. On the other hand, if there is a problem with the vehicle 3, the vehicle 3 does not start wide-area wireless communication and does not perform the subsequent sequences in the D-WPT process.
[0081] 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 the vehicle 3 is planning to enter or has entered. The first communication device 120 to communicate with is selected based on the relative positional relationship between the current location of the vehicle 3 and the location of the D-WPT lane. On the power supply device 5 side, when the first communication device 120 receives a D-WPT service request signal while waiting for a request A30 from the vehicle 3, the state of the power transmission process transitions to communication setup and D-WPT service request A60. Various pieces of information related to 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.
[0082] FIG. 8 is a sequence diagram showing a case where communication is performed between the vehicle 3 and the supply device 5 using wide-area wireless communication.
[0083] 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 required power. The vehicle ECU 330 calculates the required power based on the SOC (State Of Charge) of the battery 320. 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.
[0084] 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.
[0085] 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.
[0086] 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.
[0087] 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.
[0088] 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.
[0089] 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 communication setup and D-WPT service request A60 state, 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.
[0090] Returning to Figure 7, the D-WPT service session A70 transmits power contactlessly from the power transmitting side resonant circuit 240 of the supplying device 5 to the power receiving side 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 starts 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.
[0091] 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).
[0092] [Details of the D-WPT Service Session A70] Here, detailed activities of the D-WPT service session A70 will be described.
[0093] 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.
[0094] 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 secondary device 22, the circuit topology of the secondary device 22, the self-resonant frequency of the secondary device 22, and the number of secondary coils 21.
[0095] 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 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 third communication device 340 of the vehicle 3 receives the compatibility information of the power transmitting device 10 from the supplying device 5.
[0096] 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.
[0097] 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.
[0098] The name of each element will be described in detail. Note that, in the following, each element of the compatibility information transmitted from the vehicle 3 to the supply device 5 will be described, and the explanation of the 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.
[0099] The gap class is information indicating the gap class that the secondary device 22 can receive power from. The WPT power class is information indicating the power class that the secondary device 22 can receive power from. 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 or not the drive frequency can be adjusted. The WPT type is information indicating the shape type of the secondary device 22, and indicates the coil shape of the secondary coil 21. Examples of WTP types include circular and solenoid. The WPT circuit topology is information that indicates the connection structure between the secondary coil 21 and the resonant capacitor. The WPT circuit topology can be either series or parallel. The detailed alignment method is information indicating the method to be used when alignment is performed. The pairing method is a method for performing pairing in which the vehicle 3 identifies the supplying device 5. The alignment method is a method for confirming the relative positions of secondary device 22 and primary device 13 before starting power transmission.
[0100] Detailed alignment A120 in the lateral direction of the vehicle will now be described. The vehicle 3 performs a detailed lateral vehicle alignment A120 prior to or in parallel with the pairing and alignment check A130. The vehicle ECU 330 begins the detailed lateral vehicle alignment A120 when it determines that the vehicle 3 is approaching or entering an area where a supply device 5 is installed (WPT lane).
[0101] 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.
[0102] The vehicle lateral fine alignment A120 is basically performed manually or automatically on the vehicle 3 side. The vehicle lateral fine alignment A120 can be linked with an ADAS (Automated Driving Assistance System).
[0103] The vehicle lateral detailed positioning A120 activity may then continue based on the positioning 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.
[0104] The pairing and alignment check A130 will now be described. Here, pairing and alignment check will be explained separately.
[0105] First, pairing will be described. The P2PS interface, which provides short-range wireless communication, ensures that the primary device 13 and secondary device 22 are uniquely paired. The pairing state process is as follows:
[0106] 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 it with the vehicle's own position information obtained by the GPS receiver 360 to recognize the approach or entry based on the straight-line distance, etc. The vehicle 3 transmits to the server 30 via wide-area wireless communication which D-WPT lane it has approached. In short, 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.
[0107] 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.
[0108] 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.
[0109] 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.
[0110] 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.
[0111] 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 completed, the state transitions to alignment check.
[0112] Next, the alignment check will be described. 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).
[0113] 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.
[0114] 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 the allowable range. When the magnetic coupling check A140 is completed, the state transitions to power transfer execution A150.
[0115] The execution of power transmission A150 will 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 vehicle model 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.
[0116] 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.
[0117] 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 tries to keep the current and voltage fluctuations within their ranges and maximize the transmitted power during the transition.
[0118] 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.
[0119] 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.
[0120] The power control in the power transmitter ECU 110 and the power receiving device 20 may interfere with each other, especially when the supply 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 regeneration control of the relatively small battery 320 in the vehicle 3. If possible, it is desirable for the supply device 5 to be able to detect a mismatch between the power control target and the limit and adjust the power transmission to resolve the mismatch.
[0121] If power transmission is interrupted for a short period while the secondary device 22 is still above the primary device 13, for example, if the foreign object detection device 140 detects a foreign object on the primary device 13, or if misalignment of the secondary device 22 causes low magnetic coupling, 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.
[0122] 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 the supplying device 5 essentially decides to transition to end power transfer A170 and then begins reducing the voltage to stop the power transfer.
[0123] 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.
[0124] The termination of power transmission A170 will now be described. In this state, the supplying device 5 reduces the transmitted power to zero and stores 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 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 terminating power transmission A170 is shown in Figure 9.
[0125] FIG. 9 is a sequence diagram showing the operation after the power supply from the supply device 5 to the vehicle 3 during travel is completed.
[0126] When the power receiving device 20 of the vehicle 3 finishes receiving power from the supply device 5 (step S21), the vehicle 3 transmits power receiving end information to the server 30 (step S22). In step S22, the power receiving end information is transmitted from the third communication device 340 of the vehicle 3. The power receiving end information includes, as information related to the reception of power 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.
[0127] 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.
[0128] 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.
[0129] 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.
[0130] 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).
[0131] 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).
[0132] 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).
[0133] 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. 8. 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. 8.
[0134] 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. 8.
[0135] 9 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 facility 2, 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.
[0136] Returning to FIG. 7 , 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. 7 , the state transitions from the end of power transfer A170 to the pairing and alignment check A130. As shown in FIG. 7 , 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.
[0137] 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.
[0138] Furthermore, the D-WPT service session A70 is not limited to transitions such as those indicated by the transition lines in Figure 7. When activities after the pairing and alignment check A130 in the D-WPT service session A70 are completed, if the conditions for the power transmission process to remain in the D-WPT service session A70 are met, the state 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.
[0139] [Details of vehicle 3A for power transmission execution A150] Next, the execution A150 of power transmission will be described. Fig. 10 is a sequence diagram showing the operation using P2PS between the vehicle 3A and the supply device 5 in the execution A150 of power transmission.
[0140] As shown in FIG. 10, the vehicle ECU 330 includes power receiving devices 201 to 20 n Specifically, the vehicle ECU 330 determines whether or not there is a faulty power receiving device 20 among the plurality of power receiving devices 201 to 202 (step S41).n For each of the power receiving devices 201 to 202, a predetermined abnormality checking operation is performed, for example, the power receiving device 20 is determined to be faulty if the current value from an ammeter (not shown) or the voltage value from a voltmeter (not shown) is less than a predetermined value. n The vehicle ECU 330 may determine that the power receiving device 201 to the power receiving device 202 are malfunctioning if the power receiving device 201 receives electric power from the power supply device 5 or the magnetic coupling is less than a predetermined value. n If it is determined that there is a faulty power receiving device 20 among them (step S41: Yes), the charging relay 310 corresponding to the faulty power receiving device 20 is set to an open state (step S42), and the process proceeds to step S43. This makes it possible to suppress unnecessary charging of the vehicle 3A. In response to this, the vehicle ECU 330 controls the power receiving devices 201 to 20 n If it is determined that there is no faulty power receiving device 20 (step S41: No), the process proceeds to step S43.
[0141] Next, the vehicle ECU 330 controls the power receiving devices 201 to 202 to receive power from the supply device 5. n In this case, the vehicle ECU 330 determines the power of each of the plurality of power receiving devices 201 to 202 (step S43). n Based on the coil shape of each primary coil 11, the circuit specifications such as the arrangement position of the primary coil 11 in the vehicle 3A, the coil gap between the primary coils 11, the vehicle speed of the vehicle 3A, and the SOC of the battery 320, the power receiving devices 201 to 20 n Each determines the power it receives from the supply device 5.
[0142] Thereafter, the vehicle ECU 330 controls the power receiving device 201 to the power receiving device 202. n In this case, the vehicle ECU 330 calculates the total power by adding up the maximum value of the power received from the power supply device 5 (step S44). n The total power that each receives from the power supply device 5 is calculated.
[0143] Subsequently, the vehicle ECU 330 transmits the power information and the total power information to the supply device 5 (step S45). n The corresponding fourth communication devices 3501 to 350 n 2, the power receiving device 201 to the power receiving device 20 n Each of the power receiving devices 201 to 202 transmits power information relating to the power it receives from the power supply device 5. In this case, the vehicle ECU 330 n The corresponding fourth communication devices 3501 to 350 n Furthermore, the vehicle ECU 330 causes the power receiving devices 201 to 20 to transmit power information by a modulated signal. n The maximum value of the power received from the power supply device 5 and the power receiving devices 201 to 20 n The third communication device 340 is made to transmit total power information relating to the total power obtained by adding up the maximum values of the power received by each device. The reason for transmitting the total power information is that the capacity of the battery 320 varies depending on the type of vehicle 3, and the demand for driving power fluctuates suddenly. One example of this sudden fluctuation is sudden regenerative braking. When regenerative braking is performed while traveling in a D-WPT lane, priority is given to regenerative braking, and therefore the received power from the power receiving device 20 is supplied to the battery 320 in addition to the regenerated power. In this case, in order to protect the battery 320 from overcharging, it is necessary for the power receiving device 20 to adjust the transmitted power. For this reason, the vehicle ECU 330 controls the power receiving devices 201 to 20. n The vehicle ECU 330 transmits the total power obtained by adding up the maximum value of the power that each vehicle receives from the supply device 5 to the supply device 5. The vehicle ECU 330 may transmit the power information and the total power information to the server 30. In this case, the server 30 transmits the power information and the total power information received from the vehicle 3A to the supply device 5.
[0144] Thereafter, the supplying device 5 transmits electric power to the vehicle 3A based on the combined power information and the total power information transmitted from the vehicle 3A (step S46). Specifically, the power transmitting ECU 110 of the supplying device 5 transmits electric power to the vehicle 3A based on the combined power information and the total power information transmitted from the vehicle 3A (step S46). nBased on the amount of power that each of the power receiving devices 201 to 202 can receive, the power transmitting ECU 110 transmits power to the segments 7 in a contactless manner. n The power receiving devices 201 to 20 are configured so that the total power does not exceed the maximum power that each receives from the power supply device 5. n Each vehicle transmits the power it can receive to segment 7. This makes it possible to protect battery 320 from overcharging even when regenerative power is generated in vehicle 3A. After power transmission execution A150 ends, the state transitions to power transmission end A170.
[0145] [Details of vehicle 3B for power transmission execution A150] Next, execution A150 of power transmission will be described. Fig. 11 is a sequence diagram showing the operation using P2PS between the vehicle 3B and the supply device 5 in execution A150 of power transmission. In Fig. 11, steps S51 and S52 correspond to steps S41 and S42 in Fig. 10, respectively, and therefore detailed description thereof will be omitted.
[0146] In step S53, the vehicle ECU 330 controls the power receiving device 201 to the power receiving device 202. n Set the respective identification information (coil ID).
[0147] Next, the vehicle ECU 330 controls the power receiving device 201 to the power receiving device 202. n The position and power of each coil are determined (step S54).
[0148] Thereafter, the vehicle ECU 330 controls the power receiving device 201 to the power receiving device 202. n The maximum value of the power that each of them receives from the power supply device 5 is added together to calculate the total power (step S55).
[0149] Subsequently, the vehicle ECU 330 transmits the power information and the total power information to the supply device 5 (step S56). nThe maximum value of the power received from the power supply device 5 and the power receiving devices 201 to 20 n The vehicle ECU 330 causes the third communication device 340 to transmit total power information relating to the total power obtained by adding up the maximum values of the power received by each of the power receiving devices 201 to 20. n The corresponding identification information, power receiving device 201 to power receiving device 20 n Position information relating to the position of each vehicle 3B and power receiving devices 201 to 20 n Each of the vehicles causes the fourth communication device 350 to transmit power information relating to the power received from the supply device 5. In this case, the vehicle ECU 330 causes the fourth communication device 350 to transmit the identification information, position information, and power information by a modulated signal.
[0150] Thereafter, the supplying device 5 transmits power to the vehicle 3B based on the identification information, the position information, the power information, and the total power information transmitted from the vehicle 3B (step S57). n Based on the corresponding identification information, position information, and power information, the power receiving devices 201 to 20 n In this case, the power transmission ECU 110 transmits the power that each of the power receiving devices 201 to 200 can receive in a contactless manner. n The power receiving devices 201 to 20 are configured so that the total power does not exceed the maximum power that each receives from the power supply device 5. n Each of the power receiving devices 201 to 202 transmits the power that it can receive to the segment 7. This makes it possible to protect the battery 320 from overcharging even when regenerative power is generated in the vehicle 3B. n Even if the fourth communication device 350 is installed in the vehicle 3B, only one fourth communication device 350 can communicate with the power receiving device 201 to the power receiving device 202. n It is possible to transmit power appropriate for each of them. After the execution of power transmission A150 is completed, the state transitions to the end of power transmission A170.
[0151] According to the embodiment described above, the vehicle ECU 330 receives power from the power supply device 5 via the power receiving devices 201 to 20. n In order to determine the respective powers and transmit power information relating to the determined powers to the supply device 5, the power receiving devices 201 to 20 are provided on the vehicle 3 side. n Even when the battery is provided with the battery, charging is possible.
[0152] According to the embodiment, the vehicle ECU 330 controls the power receiving device 201 to the power receiving device 202. n The corresponding fourth communication devices 3501 to 350 n 2, the power receiving device 201 to the power receiving device 20 n Each of the power receiving devices 201 to 20 transmits power information relating to the power received from the power supply device 5. n The power reception can be controlled independently for each device.
[0153] According to the embodiment, the vehicle ECU 330 controls the power receiving device 201 to the power receiving device 202. n The maximum value of the power received from the power supply device 5 and the power receiving devices 201 to 20 n Total power information relating to the total power obtained by adding up the maximum values of the power received by each of the vehicles is transmitted to the third communication device 340. This makes it possible to protect the battery 320 from being overcharged even when regenerative power is generated in the vehicle 3A.
[0154] According to the embodiment, the vehicle ECU 330 controls the power receiving device 201 to the power receiving device 202. n The corresponding identification information, power receiving device 201 to power receiving device 20 n The position information of each of the power receiving devices 201 to 20 n Each of the fourth communication devices 350 transmits power information relating to the power received from the power supply device 5. As a result, only one fourth communication device 350 can control the power receiving devices 201 to 20. n It is possible to transmit power that is appropriate for each.
[0155] According to the embodiment, the vehicle ECU 330 includes a plurality of power receiving devices 201 to 20 n If there is a faulty power receiving device 20 among them, the charging relay 310 corresponding to the faulty power receiving device 20 is set to an open state (open state), thereby making it possible to suppress unnecessary charging of the vehicle 3A.
[0156] Furthermore, in the wireless power transmission system according to the embodiment, the above-described "power receiving device" can be read as "means" or "circuit," etc. For example, the power receiving device can be read as power receiving means or a power receiving circuit.
[0157] In addition, the program to be executed by the wireless power transmission system according to the embodiment is provided as file data in an installable or executable format recorded on a computer-readable recording medium such as a CD-ROM, a flexible disk (FD), a CD-R, a DVD (Digital Versatile Disk), a USB medium, or a flash memory.
[0158] In the explanation of the flowcharts in this specification, the order of processing between steps is clearly indicated using expressions such as "first," "then," and "continue," but the order of processing required to implement this embodiment is not uniquely determined by these expressions. In other words, the order of processing in the flowcharts described in this specification can be changed within a consistent range.
[0159] Further advantages and modifications will readily occur to those skilled in the art. The invention in its broader aspects is not limited to the specific details and representative embodiments shown and described above. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.
[0160] Although some of the embodiments of the present application have been described in detail above with reference to the drawings, these are merely examples, and the present invention can be implemented in other forms that have undergone various modifications and improvements based on the knowledge of those skilled in the art, including the aspects described in the disclosure of the present invention. [Explanation of symbols]
[0161] 1. Wireless power transmission system 2 Supply equipment 3 vehicles 4 road 5 Feeding device 6 AC power supply 10 Power transmission equipment 11 Primary coil 201~20 n Powered Device 21 Secondary coil 130 First communication device 140 Second communication device 3101~310 n Charging relay 320 Battery 330 Vehicle ECU 340 Third communication device 3501~350 n Fourth communication device
Claims
1. A wireless power transmission system that transmits power from a roadside supply device to a vehicle in a non-contact manner, The supply device comprises: a first communication device capable of wide-area wireless communication; a second communication device capable of short-range wireless communication; Equipped with The vehicle is a plurality of power receiving devices that receive power from the power supply device; a third communication device capable of wide-area wireless communication; a plurality of fourth communication devices capable of short-range wireless communication and provided in association with the plurality of power receiving devices, respectively; a processor; Equipped with The processor: determining the power to be received by each of the plurality of power receiving devices; calculating a total power by adding up the maximum values of the power of each of the plurality of power receiving devices; causing the third communication device to transmit to the supplying device total power information relating to the maximum value of the power of each of the plurality of power receiving devices and the total power; causing each of the plurality of fourth communication devices to transmit power information regarding the power of each of the plurality of power receiving devices to the supplying device; Wireless power transfer system.
2. 2. The wireless power transmission system according to claim 1, The supply device comprises: transmitting power to each of the plurality of power receiving devices based on the total power information received via the first communication device and the power information of each of the plurality of power receiving devices received via the second communication device; Wireless power transfer system.
3. 2. The wireless power transmission system according to claim 1, The processor: setting identification information for identifying each of the plurality of power receiving devices; determining the power to be received by each of the plurality of power receiving devices; transmitting position information of each of the plurality of power receiving devices, the identification information, and power information regarding the power of each of the plurality of power receiving devices; Wireless power transfer system.
4. A wireless power transmission system that transmits power from a roadside supply device to a vehicle in a non-contact manner, The supply device comprises: a first communication device capable of wide-area wireless communication; a second communication device capable of short-range wireless communication; Equipped with The vehicle is a plurality of power receiving devices that receive power from the power supply device; a processor; a third communication device capable of wide-area wireless communication; a fourth communication device capable of short-range wireless communication; Equipped with The processor: setting identification information for identifying each of the plurality of power receiving devices; determining the power to be received by each of the plurality of power receiving devices; calculating a total power by adding up the maximum values of the power of each of the plurality of power receiving devices; causing the third communication device to transmit to the supplying device total power information relating to the maximum value of the power of each of the plurality of power receiving devices and the total power; causing the fourth communication device to transmit to the supplying device location information of each of the plurality of power receiving devices, the identification information, and power information regarding the power of each of the plurality of power receiving devices; Wireless power transfer system.
5. 2. The wireless power transmission system according to claim 1, The vehicle is A battery, a charging relay provided in each of the plurality of power receiving devices, the charging relay electrically connecting the power receiving device and the battery; Equipped with The processor: When any one of the plurality of power receiving devices has a fault, a charging relay electrically connected to the power receiving device in which the fault has occurred is opened. Wireless power transfer system.
Citation Information
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