Non-contact power transmission system, moving body, and non-contact power transmission method

Abstract

The invention provides a non-contact power transmission system, a moving object, and a non-contact power transmission method. A non-contact power transmission system according to an embodiment of the present invention supplies power in a non-contact manner from a power supply device provided on a movement path of a moving body to a power reception device provided on the moving body, the power reception device being provided with a control unit. The control unit transmits a pairing signal from the power receiving device to the power supply device when the distance or time corresponding to the position of the moving body and the installation position of the power supply device is less than a threshold value, and transmits the pairing signal from the power receiving device to the power supply device when a response from the power supply device to the pairing signal is received. The operation mode of the power receiving device is converted to a power receiving mode.

Description

Technical Field

[0001] The present invention relates to a non-contact power transmission system, a mobile object, and a non-contact power transmission method. Background Art

[0002] In recent years, research and development related to charging and power supply in vehicles equipped with secondary batteries has been increasingly underway to contribute to energy efficiency, aiming to ensure convenient, reliable, sustainable, and advanced energy use. In this regard, a known technology is that, in a contactless power transmission system that supplies power from outside the vehicle to the vehicle, communication between the power transmitter and the power receiver is achieved by superimposing a communication signal on a power supply signal transmitted from the power transmitter to the power receiver (see, for example, Japanese Patent Application Publication No. 2013-247807 and Japanese Patent Application No. 5348325). Summary of the Invention

[0003] Technologies related to charging and powering vehicles equipped with secondary batteries have the following problem: while a mobile object such as a vehicle is moving, the distance between the power transmitting side and the power receiving side changes, sometimes preventing proper power transmission.

[0004] The present application aims to provide a non-contact power transmission system, a mobile body, and a non-contact power transmission method that can achieve more appropriate power transmission control even when the mobile body is moving. Furthermore, the present application contributes to energy efficiency.

[0005] A contactless power transmission system according to a first embodiment of the present invention supplies power in a contactless manner from a power supply device provided on a moving path of a mobile body to a power receiving device provided on the mobile body, wherein the power receiving device includes a control unit that, when a distance or time corresponding to a position of the mobile body and a location where the power supply device is provided becomes less than a threshold, sends a pairing signal from the power receiving device to the power supply device, and, when a response to the pairing signal is received from the power supply device, switches an operation mode of the power receiving device to a power receiving mode.

[0006] The second option may be based on the non-contact power transmission system of the above-mentioned first option, and the non-contact power transmission system may also include a position detection unit, which detects the position of the power supply device existing in the moving direction of the mobile body based on the position of the mobile body and map information, and / or detects the position of the power supply device based on the analysis result of the image captured by the camera mounted on the mobile body, and the control unit sends the pairing signal when the distance to the position corresponding to the installation position of the power supply device detected by the position detection unit becomes less than a specified distance.

[0007] A third option, based on the contactless power transmission system of the first option, may be that the contactless power transmission system further includes a position detection unit, which detects the position of the power supply device in the direction of travel of the mobile body based on the position of the mobile body and map information, and / or detects the position of the power supply device based on the analysis result of the image captured by the camera mounted on the mobile body, and the control unit sends the pairing signal when the time from the mobile body to the power supply device detected by the position detection unit becomes less than a specified time.

[0008] A fourth aspect is the contactless power transmission system of the first aspect, wherein the control unit may transmit a pairing signal from the power receiving device to the power supply device when the power receiving device is in a weak coupling state with the power supply device in a weak magnetic field within a predetermined range.

[0009] A fifth aspect of the present invention is a moving body equipped with a power receiving device that receives power in a contactless manner from a power supply device installed on a moving path, wherein the moving body includes a control unit that, when a distance or time corresponding to the position of the moving body and the installation location of the power supply device becomes less than a threshold value, transmits a pairing signal from the power receiving device to the power supply device, and, when a response to the pairing signal is received from the power supply device, switches the operation mode of the power receiving device to the power receiving mode.

[0010] A contactless power transmission method according to a sixth aspect of the present invention provides contactless power supply from a power supply device provided on a moving path of a mobile body to a power receiving device provided on the mobile body, wherein the power receiving device performs the following processing: when a distance or time corresponding to a position of the mobile body and a setting position of the power supply device becomes less than a threshold value, a pairing signal is sent from the power receiving device to the power supply device; and when a response to the pairing signal is obtained from the power supply device, an operation mode of the power receiving device is changed to a power receiving mode.

[0011] According to the first to sixth aspects described above, even when the mobile object is moving, more appropriate control of power transmission can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 1 is a schematic diagram of the configuration of a contactless power transmission system according to an embodiment.

[0013] Figure 2 It is a diagram showing an example of the configuration of a power supply device according to an embodiment.

[0014] Figure 3 It is a diagram showing an example of the structure of a vehicle according to the embodiment.

[0015] Figure 4 A diagram for explaining transitions of operation modes.

[0016] Figure 5 This is a diagram showing the relationship between the coupling state and the distance.

[0017] Figure 6 This is a diagram showing an example of a bit layout of pairing information in the embodiment.

[0018] Figure 7 This is a flowchart showing an example of the contactless power transmission process in the embodiment.

[0019] Figure 8 This is a diagram for explaining a situation in which a power supply device installed on a road is detected.

[0020] Figure 9 This is a diagram for explaining a case where a plurality of power supply devices are arranged.

[0021] Figure 10 This is a flowchart showing another example (one) of the contactless power transmission process.

[0022] Figure 11 This is a flowchart showing another example (part 2) of the contactless power transmission process. DETAILED DESCRIPTION

[0023] Hereinafter, a contactless power transmission system, a movable object, and a contactless power transmission method according to embodiments of the present invention will be described with reference to the accompanying drawings.

[0024] [System Structure]

[0025] Figure 1This is a schematic diagram of the structure of a contactless power transmission system according to an embodiment. The contactless power transmission system 1 according to the embodiment includes, for example, a power supply device 100, a vehicle 200 as an example of a mobile object, and an information processing server 300. The power supply device 100 and the information processing server 300 communicate, for example, via a network NW. The network NW includes, for example, the Internet, a WAN (Wide Area Network), a LAN (Local Area Network), a cellular network, a public line, a supplier device, a wireless base station, and the like. It should be noted that in the contactless power transmission system 1, the vehicle 200 can also communicate with the information processing server 300 via the network NW using an onboard communication device. Furthermore, in the contactless power transmission system 1, the power supply device 100 and the vehicle 200 communicate using other communication methods described later. Furthermore, in the contactless power transmission system 1, the vehicle 200 is, for example, an electric vehicle such as an electric motor vehicle, a hybrid vehicle, or a fuel cell vehicle. It should be noted that, in addition to the vehicle 200, the mobile object according to the embodiment may also be an object capable of moving on a moving path, such as an electric robot. Furthermore, the mobile object may or may not carry a person. In addition, the mobile object may not only be manually driven by a passenger (driver) but may also have a structure capable of automatic driving.

[0026] The contactless power transmission system 1 supplies power from the power supply device 100 to the vehicle 200 through contactless power transmission between the power supply device 100 and the vehicle 200. It should be noted that in the contactless power transmission system 1, the power supply device 100 supplies power to multiple vehicles 200, and the vehicle 200 receives power from multiple power supply devices 100. However, for ease of explanation, the description focuses primarily on one-to-one contactless power supply.

[0027] The power supply device 100 is installed (buried) at predetermined intervals on a road surface (for example, lane L1) of a predetermined power supply lane (for example, lane L2) in lanes L1 and L2 (an example of a moving path) where the vehicle 200 can travel. Figure 1 The power supply devices 100-1, 100-2, 100-3, etc. shown in the figure).

[0028] The predetermined interval is, for example, an interval at which the magnetic field coupling regions between power supply devices 100 do not overlap. Furthermore, the predetermined interval may be set based on the type of road (e.g., general road, expressway), or may be set based on traffic regulations such as the road's speed limit. For example, power supply device 100 communicates with vehicle 200 approaching within a predetermined distance and supplies power in response to a power supply request from vehicle 200. Furthermore, power supply device 100 performs processing related to power control and power protection functions (e.g., FSA (Fail Safe Action)) in response to the request.

[0029] Vehicle 200 is equipped with a power receiving device 210. Power receiving device 210 is installed on the bottom of vehicle 200 to facilitate receiving power from a power supply device installed on the road, but the installation location is not limited to this. Power receiving device 210 performs processing related to vehicle energy management and power conservation functions (e.g., FSA). Vehicle 200 uses power stored in an onboard battery or other power storage unit to travel and supply power to other onboard equipment. While traveling on the powered lane (lane L1), vehicle 200 communicates with power supply devices 100-1 to 100-3, charging the power storage units installed in vehicle 200 using power supplied upon request. In the contactless power transmission system 1, the communication system required between power supply device 100 and vehicle 200 is a system that allows at least individual identification of vehicle 200 and enables communication while vehicle 200 is moving at a speed V1 of approximately 0 to 100 km / h. The functional configurations of the power supply device 100 and the vehicle 200 will be described in detail later.

[0030] The information processing server 300 may be, for example, a server device, a PC (Personal Computer), or a cloud server formed by cloud computing composed of one or more information processing devices. The information processing server 300 communicates with the power supply device 100, the vehicle 200, etc. to perform various processes related to electricity. The information processing server 300 may be, for example, a charging system related to contactless power supply, an electricity quotation system, or a system that cooperates with these systems. The charging system is, for example, a system for individually identifying the vehicle 200 and charging a fee based on the charged electricity. The electricity quotation system performs, for example, various controls and management for providing low-cost electricity quotation based on demand forecasts.

[0031] The information processing server 300 also manages the status of the power supply device 100 , accumulates the power supplied from each power supply device 100 - 1 to 100 - 3 to the vehicle 200 , and calculates and manages the power actually transmitted to each vehicle 200 .

[0032] [Power supply device]

[0033] Figure 2 This figure shows an example of the structure of a power supply device 100 according to an embodiment. The power supply device 100 includes, for example, a power transmission device 110 and a power supply-side communication unit 130. The power transmission device 110 includes, for example, a power supply unit 112, a power transmission power conversion unit 114, a power transmission unit 116, a power transmission-side control unit (an example of a power supply-side control unit) 118, and a communication control unit 120. The power transmission-side control unit 118 includes a voltage detection unit 118A. Part or all of the power transmission-side control unit 118 and the communication control unit 120 are implemented, for example, by a hardware processor such as a CPU (Central Processing Unit) executing a program (software). Part or all of these components may also be implemented by hardware (including circuitry) such as an LSI (Large Scale Integration), an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), a GPU (Graphics Processing Unit), or an SOC (System on Chip), or may be implemented through the collaboration of software and hardware. The program can be pre-stored in a storage device (a storage device with a non-temporary storage medium) such as the HDD (Hard Disk Drive) or flash memory of the power supply device 100, or it can be stored in a detachable storage medium such as a DVD or CD-ROM, and installed in the HDD or flash memory of the power supply device 100 by assembling the storage medium (non-temporary storage medium) in a drive device.

[0034] The power supply unit 112 of the power transmission device 110 is connected to the power transmission power conversion unit 114. The power supply unit 112 includes, for example, an AC power source such as a commercial power source, an AC-DC converter that converts the AC power into DC power, and capacitors for power smoothing. For example, the power supply unit 112 converts the AC power supplied from the AC power source into DC power using the AC-DC converter. Furthermore, the power supply unit 112 uses capacitors to smooth the power during power conversion.

[0035] The power transmission power conversion unit 114 is connected to the power transmission unit 116. The power transmission power conversion unit 114 includes, for example, an inverter that converts DC power into AC power. The inverter includes, for example, a bridge circuit formed by a plurality of switching elements connected in a two-phase bridge, a rectifier element, and a resonant capacitor for adjusting the resonance of the coil. Details of the circuit configuration of the power transmission power conversion unit 114 will be described later.

[0036] Power transmission unit 116 transmits power to an external device (e.g., power receiving device 210 of vehicle 200) using magnetic field coupling based on magnetic field resonance, for example, by utilizing changes in a high-frequency magnetic field. In magnetic field resonance, for example, when current flows through a coil on the power transmission side, magnetic field vibrations are generated, which are then transmitted to a resonant circuit on the power reception side that resonates at the same frequency, thereby flowing current. In addition to magnetic field resonance, magnetic field coupling can also utilize known coupling methods such as electromagnetic induction. In electromagnetic induction, for example, power is transmitted using the induced magnetic flux generated between the power transmission and reception sides.

[0037] The power-transmitting-side control unit 118 comprehensively controls various functions of the power transmitting device 110 or the power supply device 100 as a whole. For example, the power-transmitting-side control unit 118 controls pairing, power transmission, and other functions based on information (e.g., pairing signals, power-receiving-side operation modes) obtained through communication between the power-supplying-side communication unit 130 and the vehicle-side communication unit 230 of the vehicle 200. The pairing signal includes, for example, the power receiving device ID, which identifies the power receiving device 210, the vehicle ID, which identifies the vehicle 200, and parameter information such as the requested power and battery voltage.

[0038] For example, the power-transmitting-side control unit 118 identifies the power receiving device 210 and vehicle 200 based on the power receiving device ID and vehicle ID, and establishes (completes) pairing. Alternatively, the power-transmitting-side control unit 118 may reference user information pre-registered based on the power receiving device ID and vehicle ID, and establish pairing if the vehicle (or user) is capable of power supply (capable of using the power supply service). The power-transmitting-side control unit 118 controls power transmission so that power is supplied to the paired vehicle 200.

[0039] The power receiving side operating mode refers to the operating mode of the power receiving device 210, described later, mounted on the vehicle 200. Examples include short-circuit mode, parameter transmission mode, standby mode, and power receiving mode. Short-circuit mode prevents unintended power reception and is used, for example, in FSA. Parameter transmission mode transmits parameter information. Standby mode, for example, waits for communication with the power supply side.

[0040] The power reception mode is a mode in which pairing is established, the power reception unit 211 and the received power conversion unit 212 are in operation and waiting for power reception, or in a state in which power reception is possible or in progress based on a predetermined frequency (required frequency for resonance).

[0041] In addition, the power transmission side control unit 118 controls the operation mode of the power transmission device 110 (power transmission side operation mode) according to the situation. For example, it includes a stop mode, a search (exploration) mode, a standby (standby) mode, and a power transmission mode. The stop mode in the power transmission side operation mode is a mode in which there is no vehicle providing service within the power transmission service area (electric road) and it is not operating. The search mode is a mode in which pairing with the vehicle 200 is established, the coupling coefficient is detected to increase, and the power transmission efficiency is ensured, and the power transmission is retained. The standby mode is, for example, a mode of waiting for communication with the power receiving side. The power transmission mode is, for example, a state in which power can be transmitted based on the required frequency or a state in which power is being transmitted (power transmission state).

[0042] For example, when pairing with vehicle 200 is established, the power transmitting-side control unit 118 changes the operating mode of the power transmitting device 110 from the stop mode to the receiving (standby) mode. Furthermore, upon receiving information such as the requested frequency for power transmission from vehicle 200 from the power receiving device 210 via the communication control unit 120, the power transmitting-side control unit 118 changes the operating mode from the receiving mode to the search mode. Furthermore, when power transmission efficiency is maintained in the search mode, the power transmitting-side control unit 118 changes to the power transmitting mode. It should be noted that, during the power transmission state in the power transmitting mode, the power transmitting-side control unit 118 may also transmit power at a pre-set drive frequency, rather than the requested frequency. The power transmitting-side control unit 118 controls the switching of each switching element of the power transmission power converter 114, turning them on (conducting) and off (disconnecting), based on the requested frequency, thereby transmitting power to the power receiving device 210 of vehicle 200. Furthermore, for example, when power transmission to the vehicle 200 becomes impossible or communication becomes impossible, the power transmitting-side control unit 118 terminates pairing and shifts the power transmitting device 110 to the stop mode.

[0043] Furthermore, the power transmission-side control unit 118 can control the charging and settlement of the amount of electricity used (kWh) after the system is used on the vehicle 200 side. Furthermore, the voltage detection unit 118A of the power transmission-side control unit 118 detects the voltage in the power transmission power conversion unit 114. Based on the waveform of the detected voltage (e.g., a rectangular wave), the power transmission-side control unit 118 obtains information (e.g., bit string information) from the vehicle side. Details of this processing will be described later. The power transmission-side control unit 118 performs the various controls described above based on various information obtained from communication between the power supply-side communication unit 130 and the vehicle-side communication unit 230, or based on information obtained based on the voltage waveform.

[0044] The communication control unit 120 controls the operation of the power supply-side communication unit 130. For example, when there are multiple power supply-side communication units 130 in the power supply device 100, the communication control unit 120 controls the operation of all power supply-side communication units 130. For example, the communication control unit 120 attempts to obtain specified information (e.g., pairing signals, information related to power transmission (e.g., requested frequency, charges after system use, information required for settlement, etc.)) through communication between the power supply-side communication unit 130 and the vehicle-side communication unit 230 of the surrounding vehicle 200 at a predetermined period or other timing. The communication control unit 120 outputs the obtained information to the power transmission-side control unit 118, or transmits information obtained from the power transmission-side control unit 118 (pairing establishment information, information required to start power transmission), etc. to the vehicle-side communication unit 230 via the power supply-side communication unit 130.

[0045] The power supply-side communication unit 130 is equipped with an antenna for wireless communication and other devices, and wirelessly communicates with external devices (e.g., information processing server 300, vehicle 200). Furthermore, the power supply-side communication unit 130 transmits and receives information related to power transmission from the power transmission device 110 to the vehicle 200. Specifically, the power supply-side communication unit 130 transmits and receives information for pairing with the vehicle 200, or for adjusting the amount of power to be transmitted, so that power is supplied to a specific vehicle 200 under the control of the power transmission-side control unit 118 and the communication control unit 120. Furthermore, the power supply-side communication unit 130 can also obtain information from other external devices via the network NW.

[0046] [vehicle]

[0047] Figure 3 2 is a diagram showing an example of the structure of a vehicle 200 according to an embodiment. The vehicle 200 includes, for example, a power receiving device 210, a rotating electric machine 220, a vehicle-side communication unit 230, a detection device 240, a vehicle sensor 250, and a driving control unit 260. Figure 1Although not shown, in addition to the aforementioned on-board devices, vehicle 200 also includes various on-board devices (e.g., various devices for driving on the road, either manually or automatically by the driver (driving control devices), navigation devices, audio devices, and other devices (examples of loads and auxiliary devices). The power receiving device 210 includes, for example, a power receiving unit 211, a power receiving power conversion unit 212, a power conversion unit 213, a power storage unit 214, a power receiving-side control unit 215, a communication control unit 216, and a position detection unit 217. The power receiving-side control unit 215 includes, for example, a voltage detection unit 215A. Some or all of the power receiving-side control unit 215, the communication control unit 216, and the position detection unit 217 are implemented, for example, by a hardware processor such as a CPU executing a program (software). Some or all of these components may also be implemented using hardware (including circuitry) such as an LSI, ASIC, FPGA, or GPU, or through the collaboration of software and hardware. The program can be pre-stored in a storage device such as an HDD or flash memory of the vehicle 200 or the power receiving device 210 (a storage device having a non-transitory storage medium), or can be stored in a removable storage medium such as a DVD or CD-ROM and installed in the HDD or flash memory of the vehicle 200 or the power receiving device 210 by assembling the storage medium (non-transitory storage medium) in a drive device.

[0048] Power receiving unit 211 of power receiving device 210 is connected to received power converter 212. Power receiving unit 211 receives power by utilizing changes in the high-frequency magnetic field transmitted from power transmitting unit 116 through magnetic field coupling such as magnetic resonance or electromagnetic induction.

[0049] The receiving power conversion unit 212 is connected to the power conversion unit 213. The receiving power conversion unit 212 includes, for example, an inverter that converts AC power into DC power and performs voltage smoothing and voltage division. The inverter includes, for example, a bridge circuit formed by multiple switching elements and rectifier elements connected in a two-phase bridge, as well as capacitors for voltage smoothing. Details of the circuit configuration of the receiving power conversion unit 212 will be described later.

[0050] For example, the power receiving device 210, which includes a power receiving unit 211 and a power receiving power conversion unit 212, controls the on / off switching of each switching element of the power receiving power conversion unit 212 based on information about the frequency of power transmission from the power transmitting device 110 under the control of the power receiving-side control unit 215, thereby receiving power transmitted from the power transmitting device 110.

[0051] The power converter 213 is connected to the rotating electrical machine 220. The power converter 213 includes, for example, a power converter that converts DC power into AC power. The power converter includes, for example, a component module and a capacitor for voltage smoothing. Details of the circuit configuration of the power converter 213 will be described later.

[0052] The rotating electric machine 220 is, for example, a three-phase AC brushless DC motor used to drive the vehicle. The rotating electric machine 220 includes a rotor with permanent magnets for excitation and a stator with three-phase stator windings that generate a rotating magnetic field to rotate the rotor. The three-phase stator windings are connected to the three-phase AC terminals of the power converter 213. The rotating electric machine 220 generates a rotational driving force by operating in a power-driven manner using the power supplied from the power converter 213. For example, when the rotating electric machine 220 is coupled to the wheels of the vehicle 200, it generates a driving force by operating in a power-driven manner using the power supplied from the power converter 213. The rotating electric machine 220 can also generate electric power by regenerating the rotational power input from the wheels of the vehicle 200. When the rotating electric machine 220 is coupled to the internal combustion engine of the vehicle 200, it can also generate electric power using the power of the internal combustion engine.

[0053] The power storage unit 214 includes, for example, a battery (an example of a secondary battery) such as a lithium-ion battery, a current sensor for detecting the battery's current, a voltage sensor for detecting the battery's voltage, and a temperature sensor for measuring the battery's temperature. In the vehicle 200, the power storage unit 214 is connected to the power conversion unit 213 and the power receiving power conversion unit 212 (described later). For example, the power storage unit 214, under the control of the power receiving-side control unit 215, receives power from the power supply device 100 or the rotating electric machine 220 and supplies the received power to the rotating electric machine 220 and various other onboard devices (loads, auxiliary equipment).

[0054] The power receiving-side control unit 215 comprehensively controls various functions of the power receiving device 210 or the entire vehicle 200. For example, the power receiving-side control unit 215 generates control signals indicating the timing for driving each switching element on (conducting) and off (disconnecting), and generates gate signals for actually driving each switching element on and off based on the control signals. For example, by controlling the switching of each switching element in the power receiving device 210, the power receiving-side control unit 215 rectifies the AC power received from the power transmitting device 110 into DC power, while also improving the power factor of the input voltage and input current.

[0055] The power receiving control unit 215 also generates specified information (e.g., pairing signals and information related to power transmission) for power transmission from the power supply device 100 and transmits the generated signal externally from the vehicle-side communication unit 230. It should be noted that the power receiving control unit 215 may transmit the pairing signal at a specified period or at other specified timings. Furthermore, upon receiving permission information (pairing completion information) indicating that power supply is possible from the power supply device 100, as well as information required to start power transmission, from the vehicle-side communication unit 230, the power receiving control unit 215 obtains the target power by synchronously driving the multiple switching elements of the power receiving device 210 on and off, performing a synchronous rectification operation, or short-circuiting the secondary coil (described later). Furthermore, the power receiving control unit 215 controls the current flowing through the power transmitting device 110, thereby performing independent power control on the power receiving device 210, such as stopping power transmission.

[0056] Information related to power transmission includes, for example, the required power and frequency for power transmission, target output (power consumption) for failsafe, and information related to various abnormalities. The required power for power transmission is the target value of power that power receiving device 210 receives from power transmitting device 110. It is set based on, for example, the target driving force of vehicle 200 or rotating electric machine 220, the power consumption of various auxiliary machines connected to power storage unit 214, and the power state (SOC) of power storage unit 214. The power state includes, for example, the remaining capacity and charge rate of power storage unit 214. The required frequency for power transmission is the frequency required for power transmission by power transmitting device 110 and is set based on the required power. The required frequency is set based on, for example, the minimum ground clearance of vehicle 200 and the layout of power receiving device 210 in vehicle 200 to minimize reductions in power transmission efficiency and output (power). The required frequency can also be set based on, for example, the power transmission status between power transmitting device 110 and power receiving device 210. Furthermore, information related to power transmission may include information required for billing and settlement after system utilization.

[0057] Furthermore, the receiving-side control unit 215 controls the operating mode of the power receiving device 210 based on the status of the vehicle 200. As described above, the operating modes include short-circuit mode, parameter transmission mode, standby mode, and power receiving mode. For example, the receiving-side control unit 215 transmits a pairing signal at a predetermined interval, ranging from several tens of μs to several milliseconds. Upon receiving a response signal to the pairing signal from the power supply device 100, the receiving-side control unit 215 changes the operating mode of the power receiving device 210 from stop mode to short-circuit mode and transmits information such as the requested frequency. Furthermore, the receiving-side control unit 215 transitions from short-circuit mode to power receiving mode and begins controlling power transmission from the power supply device 100 during the power transmission interval. Furthermore, upon completion of power reception, the receiving-side control unit 215 changes the operating mode of the power receiving device 210 from receiving mode to stop mode.

[0058] The voltage detection unit 215A of the power receiving-side control unit 215 detects the voltage of the power receiving power conversion unit 212. The voltage detection unit 215A acquires predetermined information from the power supply device 100 based on the waveform (for example, a rectangular wave) of the detected voltage.

[0059] The communication control unit 216 controls the operation of the vehicle-side communication unit 230. For example, the communication control unit 216 transmits predetermined information (e.g., parameter information such as a pairing signal) to the vehicle-side communication unit 230 at a predetermined period or other timing. Furthermore, the communication control unit 216 may transmit the predetermined information when the vehicle 200 is within a predetermined distance from the installation location (power supply interval) of the power supply device 100, based on the position of the power supply device 100 detected by the position detection unit 217.

[0060] Then, when pairing is established, information related to power transmission (for example, requested frequency, charges after system use, information required for settlement, etc.) is transmitted to the vehicle-side communication unit 230 .

[0061] The position detection unit 217 detects the position of the power supply device 100 based on the surrounding conditions of the vehicle 200 detected by the detection device 240 , information related to the vehicle 200 detected by the vehicle sensor 250 , and the like.

[0062] The vehicle-side communication unit 230 is equipped with an antenna for wireless communication and other functions, and wirelessly communicates with external devices (e.g., the information processing server 300 and the power supply device 100). Furthermore, the vehicle-side communication unit 230 transmits and receives information related to power transmission from the power supply device 100, for example. Specifically, the vehicle-side communication unit 230 transmits and receives information for pairing with the power supply device 100, or for adjusting the amount of power to be transmitted, so that power can be supplied from a specific power supply device 100 under the control of the power receiving-side control unit 215. Furthermore, the vehicle-side communication unit 230 can also obtain information from other external devices via the network NW.

[0063] The detection device 240 is a device that detects the surrounding conditions of the vehicle 200 (within a specified distance from the vehicle 200). Examples of the detection device 240 include cameras, radar devices, LIDAR (Light Detection and Ranging), and sensor fusion devices. Furthermore, based on the detection results, the detection device 240 identifies the type, shape, position (relative position), and speed (relative speed) of surrounding objects. Objects include, for example, other vehicles, pedestrians, and other traffic participants, as well as the lane in which the vehicle 200 is traveling, road markings dividing the lanes, and other road structures (road signs, medians, curbs, and traffic lights). Furthermore, based on the position information of the vehicle 200 detected by the vehicle sensor 250, the detection device 240 can also refer to map information stored in a storage unit (not shown) within the vehicle 200 to identify the surrounding road shape (e.g., the position of road markings), the powered lane, and the position of the power supply device 100 according to the position of the vehicle 200. Map information, for example, is information that represents the shape of a moving path, such as a road, by mapping it to location information (e.g., latitude and longitude) and by representing the paths of movement, such as roads, and the nodes connected by those paths. Map information may also include the curvature and slope of the moving path, as well as POI (Point of Interest) information mapped to the location information. Map information may also include information related to the location and installation interval of power supply devices 100 or power transmission devices 110 installed in a specified area, such as a road (moving path) or parking lot, as well as information related to the identification information of the power supply device 100 (power supply device ID) and the identification information of the installation interval (power supply interval ID).

[0064] The vehicle sensor 250 includes, for example, a speed sensor that detects the speed V1 of the vehicle 200, an acceleration sensor that detects acceleration, a yaw rate sensor that detects yaw rate (angular velocity), an orientation sensor that detects the orientation of the front direction of the vehicle 200, and an operation amount detection sensor installed on a driving operating part. The driving operating part includes, for example, an operating part for indicating acceleration and deceleration (for example, an accelerator pedal, a brake pedal) and an operating part for indicating steering (for example, a steering wheel). In this case, the vehicle sensor 250 may include an accelerator opening sensor, a brake pedaling amount sensor, a steering torque sensor, etc. In addition, the vehicle sensor 250 may also be provided with a position sensor that detects the position of the vehicle 200. The position sensor is, for example, a sensor that obtains position information (longitude, latitude information) from a GPS (Global Positioning System) device. In addition, the position sensor may also be a sensor that obtains position information using a GNSS (Global Navigation Satellite System) receiver.

[0065] The position detection unit 217 detects the location of the powered lane and the power supply device based on the detection results from the detection device 240. For example, the position detection unit 217 analyzes the image of the surrounding area of ​​the vehicle 200 captured by the camera using known image analysis processing, and detects the location of the powered lane and the location of the power supply device 100 based on road signs, text, and markings drawn on the road. Furthermore, when the position detection unit 217 obtains vehicle position information using a position sensor mounted on the vehicle 200, it references map information pre-stored in a storage unit, etc., to obtain the installation location of the power supply device 100 (or power supply section information).

[0066] Driving control unit 260 performs driving control by controlling at least one of the steering and speed of vehicle 200 based on the surrounding conditions detected by detection device 240 and information detected by vehicle sensors 250. Driving control includes, for example, LKAS (Lane Keeping Assistance System) control (lane keeping control) to maintain the vehicle 200 in the center of its lane (travel path) (in other words, to avoid departing from the road dividing lines that demarcate the lanes). Furthermore, driving control includes ACC (Adaptive Cruise Control), which maintains the vehicle 200 at a predetermined speed and automatically accelerates and decelerates by measuring the distance and speed difference to a preceding vehicle when approaching it; and ALC (Auto Lane Changing) control, which, upon receiving a lane change instruction from the driver through operation of a turn signal switch, executes a lane change (steering control) in the indicated direction.

[0067] [About the transition of the operating mode during contactless power supply]

[0068] Next, transitions in the respective operating modes of the power transmitting device 110 and the power receiving device 210 during contactless power feeding will be described using the drawings. Figure 4 is a diagram for explaining the transition of the action mode. Figure 4 In the example, the horizontal axis represents time, and the vertical axis represents the operation of the vehicle 200, the operation mode (VA operation) of the power receiving device 210 side, and the operation mode (GA operation) of the power supply device 100. Figure 4 As an example of the action transition, an example of a case where contactless power transmission is performed between the power supply device 100 and the power receiving device 210 when the vehicle 200 is traveling at a predetermined speed (for example, about 80 [km / h]) is shown. The following describes the action transition accompanying the passage of time. It should be noted that Figure 4 In the example, during contactless power supply, abnormality detection is always performed on the power receiving device 210 side and the power supply device 100 side. When an abnormality is detected, FSA (Fail Safe Action) (VA side FSA, GA side FSA) is executed to control to the safe side.

[0069] At time T1, the power receiving-side control unit 215 of the vehicle 200 communicates with the information processing server 300, for example, via the vehicle-side communication unit 230, to perform billing for contactless power supply or pre-processing (on-board device billing) for billing corresponding to the amount of power supplied. It should be noted that before time T1, the operating mode on the power receiving device 210 is in standby mode. Furthermore, during the billing process, the operating mode on the power supply device is in shutdown (OFF) mode.

[0070] At time T2, after the toll collection process is complete, power receiving device 210 positions vehicle 200 so that it can pass over power supply device 100 located on the road surface (e.g., a powered lane). In this case, positioning can be performed by driving control unit 260 based on information detected by position detection unit 217. Alternatively, an image showing the position of power supply device 100 (or the position of the powered lane) and the current position of vehicle 200 can be displayed on a display unit (not shown) mounted on vehicle 200, and the driver can manually perform positioning while observing the image displayed on the display unit. For example, if LKAS control is being executed by driving control unit 260, vehicle 200 is controlled to travel in the center of the lane. Therefore, LKAS control allows vehicle 200 to travel in the powered lane, resulting in positioning. It should be noted that during the period from time T2 to time T3, power receiving device 210 remains in the short-circuited state, and power supply device 100 transitions from stop mode to standby mode.

[0071] At time T3, when the distance between power receiving device 210 and power supply device 100 decreases to within a predetermined distance (a communicable distance) due to vehicle 200's travel, the power receiving-side control unit 215 of vehicle 200 initiates pairing based on communication (VA-GA communication) between power receiving device 210 and power supply device 100. From time T3 to T4, the power receiving-side control unit 215 repeatedly performs a transmission mode (transmitting parameter information (ID, required power, battery voltage, etc.)) and a standby mode until the power transmission efficiency exceeds a predetermined value (e.g., greater than 0%). Meanwhile, the power transmitting-side control unit 118 of power supply device 100 repeatedly performs a reception mode and a search mode. In the search mode, for example, the efficiency is determined based on the correspondence information between power (transmitted power) and efficiency for power transmission according to horizontal distance (relative movement between the primary and secondary coils in a direction parallel to the road surface) in the contactless power transmission system 1 according to a predetermined embodiment, based on the correspondence information. Furthermore, power transmission control unit 118 performs an efficiency assessment based on the voltage-to-current ratio. If the ratio is below a specified value, it outputs information to that effect to power receiving device 210, initiating a retry. In other words, in this embodiment, even when the transmission efficiency is unsuitable for power supply, communication related to the pairing described above can be performed. For example, if vehicle 200 is traveling at 80 km / h, the assumed period from time T3 to T4 (the assumed communication completion time) is approximately 22.5 msec.

[0072] At time T4, the efficiency of power transmission becomes greater than a specified value, so power transmission control is performed. For example, on the power supply device 100 side, power control (GA power control) is performed to transmit power corresponding to the required power specified by the parameter to the outside. In addition, on the power receiving device 210 side, power control (VA charging (power reception) control) is performed to receive the power transmitted from the power supply device 100 and store the power in the power storage unit 214 mounted on the vehicle 200. That is, when the power transmission efficiency between the power supply device 100 and the power receiving device 210 is below the specified value, the power supply device 100 communicates with the power receiving device 210 (pairing communication), and when the efficiency becomes greater than the specified value, the power supply control to the power receiving device 210 is performed. As a result, when the power transmission efficiency is poor, pairing communication can be completed in advance, and when the power transmission efficiency is good, power supply can be performed more efficiently.

[0073] At time T5, the efficiency of power transmission becomes less than the specified value, so the power supply operation is terminated at this time point. Thus, power supply control using effective power transmission can be performed. For example, when the vehicle 200 is traveling at 80 [km / h], the assumed period from time T4 to T5 (the assumed power transmission time) is about 18 [msec]. It should be noted that since a plurality of power supply devices 100 are arranged at specified intervals on the power supply lane, the power supply is performed by each power supply device 100. Figure 4 The control shown above allows the vehicle 200 to be charged to the required power. When the power supply is completed, the power amount accumulated so far is accumulated, and the corresponding request processing (billing processing) is executed.

[0074] It should be noted that while the above processing illustrates a case where vehicle 200 is traveling at a high speed (e.g., 80 km / h), similar control can be applied at lower speeds or when the vehicle is parked. That is, the processing of this embodiment is broadly applicable, for example, in scenarios where vehicle 200 has a speed V1 between 0 and 100 km / h. Regarding power supply during a parked state, power control is performed based on a preset rated time, such as 1, 3, or 10 seconds.

[0075] [About pairing based on VA-GA communication]

[0076] Next, the pairing process using VA-GA communication described above will be described in detail. In this embodiment, for example, a pairing signal (parameter) is transmitted from vehicle 200 to power supply device 100 in a weak magnetic field coupling state (hereinafter referred to as a weak coupling state). Upon receiving a response indicating the start of power transmission from power supply device 100 (e.g., power transmission efficiency exceeding a specified value), power receiving device 210 is transitioned from standby mode to power receiving mode.

[0077] In the embodiment, when vehicle 200 enters the weak coupling state immediately before reaching power supply device 100 , communication control unit 216 transmits pairing information (pairing signal) from power receiving device 210 . Figure 5 is a graph showing the relationship between coupling state and distance. Figure 5 In the example, the horizontal axis represents the distance between the power transmitting device 110 and the power receiving device 210, and the vertical axis represents the coupling coefficient between the power transmitting side and the power receiving side (an index value indicating the strength of the coupling state such as magnetic field coupling).

[0078] exist Figure 5In the example, the closer the distance between the power supply and power receiving sides is, the larger the coupling coefficient becomes on the curve. Furthermore, even in a weak coupling state (e.g., a coupling coefficient of approximately 0.1) where the power supply and power receiving sides are separated, current can be induced from power receiving device 210 to power transmitting device 110. Therefore, communication control unit 216 transmits pairing information to power supply device 100 when the weak coupling state falls within a predetermined range (e.g., a coupling coefficient of approximately 0.1 to 0.3) just before vehicle 200 reaches power supply device 100.

[0079] In this case, communication control unit 216, for example, switches the signal (carrier wave) used for contactless power transmission to power transmission device 110 at a predetermined ratio, thereby generating two levels of digital signals, namely dominant (superior) and recessive (inferior), and superimposing the pairing information on the carrier wave. This carrier wave is, for example, the time-series waveform of the (induced) current measured on the power supply side. Communication control unit 216 transmits pairing information by modulating the carrier wave amplitude caused by varying the switching ratio.

[0080] The power transmission-side control unit 118 of the power supply device 100 in the embodiment demodulates the current (the aforementioned carrier wave) received by the power transmission unit 116 to acquire the contents of the pairing information.

[0081] It should be noted that in a weak coupling state, the coupling state may become unsustainable due to factors such as the surrounding environment, so the time required to complete pairing needs to be shortened. For example, assuming that the communication completion time in a weak coupling state is set to 10 msec, since the current during resonance to the power transmission device 110 is used as the signal, it must be transmitted at approximately 85 kHz, and the signal that can be transferred in this case is approximately 85 kbps. Therefore, the amount of data that can be transmitted in 10 msec is 850 bits in one direction. Considering bidirectional transmission and reception multiple times (for example, approximately three times), it is desirable to limit the data to approximately 8 bytes. Therefore, in this embodiment, the pairing information data is controlled to be within 8 bytes.

[0082] Figure 6 This is a diagram showing an example of a bit layout of pairing information in the embodiment.

[0083] exist Figure 6 In the example of , the horizontal direction indicates the bit string of each byte, and the vertical direction indicates the position of each byte 1 to 8. The pairing information in the embodiment may include not only the power receiving device ID and the vehicle ID, but also other information related to power transmission.

[0084] exist Figure 6The pairing information shown, for example, stores information such as DLC (Data Length Code), power supply section ID as identification information of the power receiving section, power receiving device ID or vehicle ID, vehicle classification (for example, ordinary automobile, truck, bus, etc.), vehicle status (for example, whether it is in a state where power can be received (or a state where power needs to be received), allowable charging power (for example, target power, required power), and resonance frequency (required frequency) during the period from the start mark (SOF) to the end mark (EOF) of the data. It should be noted that Figure 6 The "reservation" area shown may be information stored on the power supply device 100 side or a reserve area. In addition, the pairing information may also include battery voltage information. In addition, the type, order, and number of bits stored as the pairing signal are not limited to Figure 6 For example, in Figure 6 When the amount of data displayed is smaller, this can be addressed by reducing the number of bits in the specified items (e.g., the power supply interval ID) or by reducing the number of items such as "reservation." By storing the information required for contactless power supply within 8 bytes, more appropriate information for pairing can be transmitted in a weakly coupled state.

[0085] [Processing Flow]

[0086] Figure 7 This is a flowchart showing an example of a non-contact power transmission process in the embodiment. Figure 7 The processing of the present invention mainly involves sending pairing information among various processing executed in the contactless power transmission processing, and performing power reception control after pairing. Figure 7 The processing can be executed repeatedly at the specified timing. Figure 7In the example, the communication control unit 216 monitors the magnetic field coupling state with the power supply device 100 and determines whether it is a weak coupling state with a coupling degree within a specified range (step S200). If it is determined to be a weak coupling state, the communication control unit 216 transmits a signal (carrier wave) containing pairing information from the power receiving device 210 to the coupled power supply device 100 (step S210). Next, the communication control unit 216 determines whether a specified response (information indicating the start of power transmission) to the pairing signal has been received from the power supply device 100 (step S220). If it is determined that a response has been received, the communication control unit 216 causes the power receiving device 210 to transition from the sleep mode to the power receiving mode, enabling power reception (step S230), and executes power reception control (step S240). This concludes the flowchart. If it is determined that the weak coupling state is not present in step S200, or if it is determined that no response has been received from the power supply device 100 in step S220, the flowchart concludes.

[0087] Thus, according to the embodiment, in a contactless power transmission system 1 that performs contactless power supply from a power supply device 100 provided on a moving path of a vehicle 200 (an example of a mobile body) to a power receiving device 210 provided on the vehicle 200, the power receiving device 210 includes a communication control unit 216. When the power receiving device 210 and the power supply device 100 are in a weakly coupled state, the communication control unit 216 transmits pairing information from the power receiving device 210 to the power supply device 100, and when a response is received from the power supply device 100, the communication control unit 216 changes the operation mode of the power receiving device 210 to the power receiving mode. This enables more appropriate control of power transmission even when the vehicle 200 is moving.

[0088] Furthermore, according to the embodiment, pairing can be performed more quickly and reliably. Furthermore, according to the embodiment, weak magnetic field coupling between VA (power receiving device 210) and GA (power supply device 100) can be utilized to transmit pairing information from the VA side using the power transmission frequency.

[0089] Furthermore, according to the embodiment, for example, the power transmission coil on the power supply device 100 can be used for communication functions for transmitting pairing information, thereby eliminating the functions of the communication control unit 120, the power supply communication unit 130, and the vehicle communication unit 230. This can reduce the costs of the power supply device 100 and the vehicle 200.

[0090] [About the timing of sending the pairing]

[0091] Next, the timing for transmitting pairing information via VA-GA communication will be described in detail. In this embodiment, when the distance or time corresponding to the location of vehicle 200 and the installation location of power supply device 100 becomes less than a threshold, a pairing signal is transmitted from power receiving device 210 to power supply device 100. Upon receiving a response to the pairing signal from power supply device 100, the operating mode of power receiving device 210 is transitioned to power receiving mode.

[0092] Figure 8 1 is a diagram for explaining the detection of the power supply device 100 installed on the road. Figure 8 In the example, a power transmission device 110 is buried under the road RD1, and a position determination member 150 for externally determining the position of the power supply device 100 in the road area is provided above the power transmission device 110 (on the ground side). The position determination member 150 is, for example, a member that allows the signal (radio wave) from the power supply device 100 and the signal to the power supply device 100 to pass (without cutting off), and is a cover member (cover) that mitigates the impact (load) on the power supply device 100. In addition, at least the upper surface of the position determination member 150 is formed of a color different from the color of the road surface (or is coated with a different color) so that the position of the power supply device 100 can be determined based on the analysis results of the camera image captured by the camera of the detection device 240. There is no limitation on the shape and size of the position determination member 150. Figure 8 example.

[0093] For example, the position detection unit 217 detects a position corresponding to the power supply device 100 (or alternatively, the power transmission device 110) in the vicinity of the vehicle 200 (within a predetermined distance) by referring to map information based on the position information acquired by the vehicle sensor 250. The position corresponding to the power supply device 100 may be, for example, the center position P1 of the power supply device 100 or the position of the closest end as viewed from the vehicle 200. Alternatively, the position corresponding to the power supply device 100 may be a position P2 at which communication using the power supply-side communication unit 130 or power supply from the power supply device 100 is predicted to be possible. Position P2 is a position closer to position P1 as viewed from the vehicle 200. Position P2 is, for example, a position where the coupling coefficient (degree of coupling) in magnetic field coupling exceeds a threshold value (e.g., a coupling coefficient of approximately 0.003), but is not limited thereto and may also be a position a predetermined distance D1 closer to position P1 (on the vehicle 200 side).

[0094] Based on the position and travel direction of vehicle 200, communication control unit 216 obtains the distance D2 between vehicle 200 and position P1 corresponding to a power supply device 100 located in the travel direction. When the obtained distance D2 becomes less than a predetermined distance, communication control unit 216 transmits a pairing signal. Alternatively, communication control unit 216 may obtain distance D3 between vehicle 200 and position P2 instead of position P1, and transmit a pairing signal when vehicle 200 reaches distance D3. This allows the pairing signal to be transmitted at an appropriate time when there is a high probability of receiving a response from power supply device 100, thereby enabling more efficient communication with power supply device 100.

[0095] Alternatively, the communication control unit 216 may control the timing of sending the pairing signal based on time information instead of distance information (distances D2 and D3). In this case, the communication control unit 216 calculates the time it takes for the vehicle 200 to reach the position (e.g., position P1) with which the power supply device 100 has established a corresponding relationship based on the current position and speed V1 of the vehicle 200, and sends the pairing signal when the calculated time becomes less than a specified time. Assuming that the speed V1 of the vehicle 200 is constant, the specified time may be the time predicted for the vehicle 200 to reach position P2, or a fixed time. Alternatively, the communication control unit 216 may calculate the time it takes for the vehicle 200 to reach position P2 with which the power supply device 100 has established a corresponding relationship, and send the pairing signal when the calculated time has passed.

[0096] Alternatively, instead of calculating the distance to power supply device 100 using the vehicle 200's position and map information (or in addition to this), position detection unit 217 may perform known image analysis processing (e.g., edge extraction, feature extraction, pattern matching, etc.) on the camera image captured by the camera and, based on the analysis results, obtain the position of power supply device 100 located in the direction of travel of vehicle 200. In this case, detection device 240 detects the position of power supply device 100 based on the position of position identification member 150, road signs, text and markings drawn on the road, and the like, obtained from the analysis results of the camera image captured by the camera. By performing both acquisition of the position of power supply device 100 based on map information and acquisition of the position of power supply device 100 based on the analysis results of the camera image captured by the camera, position detection unit 217 can more accurately acquire the position of power supply device 100, thereby enabling the transmission of pairing signals at a more appropriate timing and achieving more efficient communication.

[0097] It should be noted that, for example, when vehicle 200's speed V1 is less than a predetermined speed, position detection unit 217 uses both map information and camera images to detect the position of power supply device 100 in order to ensure sufficient time until reaching power supply device 100. When speed V1 is greater than the predetermined speed, position detection unit 217 uses either map information or camera images to detect the position of power supply device 100. Furthermore, based on the weather and illumination surrounding vehicle 200, position detection unit 217 may detect the position of power supply device 100 using only map information in situations where detection by position determination unit 150 using camera images is expected to be difficult, such as on rainy days. This allows for more appropriate detection of the position of power supply device 100 depending on the conditions of vehicle 200.

[0098] Furthermore, when a plurality of power supply devices 100 are arranged, the position detection unit 217 may detect the sections thereof. Figure 9 1 is a diagram for explaining a case where a plurality of power supply devices 100 are arranged. Figure 9 In the example shown in FIG. 2 , vehicle 200B travels at a speed V1 in the travel direction (the X-axis direction in the figure) on road RD1, which is divided by road dividing lines LN1 and LN2. Furthermore, multiple positioning members 150-1 to 150-3 are arranged on road RD1 at predetermined intervals D4 along the direction in which road RD1 extends. Power supply devices 100-1 to 100-3 are buried beneath each of the multiple positioning members 150-1 to 150-3.

[0099] For example, if the predetermined interval D4 is less than the predetermined interval, position detection unit 217 detects power supply devices 100-1 to 100-3 as a single power supply device. Based on the detection results, communication control unit 216 controls the timing of transmitting the pairing signal during the power supply interval, using the position of the closest power supply device 100-1 among power supply devices 100-1 to 100-3 as a reference. This allows the pairing signal to be transmitted at a more appropriate time.

[0100] [Processing Flow]

[0101] Figure 10 This is a flowchart showing another example (one) of the contactless power transmission process. Figure 10 The processing involves the above Figure 7 Another example of sending pairing information and performing power control after pairing is shown. Figure 10 and the following Figure 11 The processing can be executed repeatedly at the specified timing. Figure 10In the example, the position detection unit 217 detects the position of the power supply device 100 in the direction of travel of the vehicle 200 (step S300). Next, the position detection unit 217 obtains the distance from the current position of the vehicle 200 to the position that has established a correspondence with the power supply device 100 (step S310). Next, the communication control unit 216 determines whether the obtained distance is less than a specified distance (step S320). If it is determined that the obtained distance is less than the specified distance, the communication control unit 216 causes the vehicle-side communication unit 230 of the vehicle 200 to send a pairing signal (step S330). Next, the communication control unit 216 determines whether a response to the pairing signal has been received from the power supply device 100 (step S340). If it is determined that a response has been received, the communication control unit 216 changes the operating mode of the power receiving device 210 from the standby mode to the power receiving mode (step S350) and executes control for power reception (charging control) (step S360). The processing of this flowchart is thus completed. If it is determined in step S320 that the distance is not less than the predetermined distance, or if no response is received from power supply device 100 even after a predetermined time has elapsed in step S340 , the process of this flowchart ends.

[0102] Figure 11 This is a flowchart showing another example (part 2) of the contactless power transmission process. Figure 11 The processing and Figure 10 Compared to the processing of steps S300 to S360 shown in FIG, the processing of steps S312 and S322 is replaced by the processing of steps S310 and S320. Therefore, the following description will mainly focus on the processing of steps S312 and S322.

[0103] exist Figure 11 In the example, after the processing of step S310, the position detection unit 217 obtains the arrival time until the position corresponding to the power supply device 100 is reached based on the current position and speed V1 of the vehicle 200 (step S312). Next, the position detection unit 217 determines whether the recognition time is less than the specified time (step S322). If it is determined that it is less than the specified time, the communication control unit 216 causes the vehicle-side communication unit 230 of the vehicle 200 to send a pairing signal (step S330) and performs subsequent processing. In addition, if it is determined in the processing of step S322 that it is not less than the specified time, or if no response is obtained from the power supply device 100 even after the specified time, the processing of this flowchart ends.

[0104] According to the embodiment described above, in a contactless power transmission system that supplies power in a contactless manner from a power supply device 100 installed on a moving path of a vehicle 200 (an example of a mobile object) to a power receiving device 210 installed on the vehicle 200, the power receiving device 210 includes a communication control unit 216. When the distance or time corresponding to the position of the vehicle 200 and the installation location of the power supply device 100 becomes less than a threshold value, the communication control unit 216 transmits a pairing signal from the power receiving device 210 to the power supply device. When a response to the pairing signal is received from the power supply device 100, the communication control unit 216 changes the operating mode of the power receiving device 210 to the power receiving mode. This enables more appropriate power transmission even when the vehicle 200 is moving.

[0105] Furthermore, according to the embodiment, pairing can be performed more reliably and at a higher speed. Furthermore, according to the embodiment, by adjusting the timing of sending the pairing signal from the power receiving device 210, the power consumption associated with sending the pairing signal can be reduced. When using weak magnetic field coupling, the timing of the transmission from the VA side is crucial. For example, when the distance between the power receiving device 210 and the power supply device 100 is too far, they are not coupled, so not only will no information be transmitted, but it will also lead to useless power consumption. In addition, when the distance is too close, it enters the power transmission range before pairing is completed, resulting in a loss of charging opportunities. Therefore, in the embodiment, a camera or the like is used to more accurately detect the position of the GA side, and the timing of transmission is calculated to transmit the pairing signal from the VA side, thereby suppressing power consumption and achieving efficient pairing communication.

[0106] [Modification]

[0107] For example, as a variation of the embodiment, when power receiving device 210 of vehicle 200 is in a weak coupling state (i.e., coupling with power supply device 100 within a predetermined range of weak magnetic fields), and when the distance or time corresponding to the position of vehicle 200 and the location corresponding to the installation location of power supply device 100 becomes less than a threshold, pairing information may be transmitted from power receiving device 210 (vehicle 200) to power supply device 100. Furthermore, as a variation of the embodiment, for example, vehicle 200 may not include vehicle-side communication unit 230. In this case, communication control unit 216 transmits pairing information from power receiving device 210 to power supply device 100 when the distance or time corresponding to the position of vehicle 200 and the installation location of power supply device 100 becomes less than a threshold and when the power receiving device 210 is in a weak coupling state (i.e., coupling with power supply device 100 within a predetermined range of weak magnetic fields).

[0108] The embodiments of the present invention are provided as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other ways and can be omitted, replaced, or modified without departing from the scope of the invention. These embodiments and their variations are included within the scope and spirit of the invention, and are also included in the invention described in the technical solutions and their equivalents.

Claims

1. A contactless power transmission system for supplying power in a contactless manner from a power supply device provided on a moving path of a moving object to a power receiving device provided on the moving object, wherein: The power receiving device includes a control unit that transmits a pairing signal from the power receiving device to the power supply device when a distance or time corresponding to the position of the mobile object and the installation position of the power supply device becomes less than a threshold value, and changes an operation mode of the power receiving device to a power receiving mode when a response to the pairing signal is received from the power supply device.

2. The contactless power transmission system according to claim 1, wherein: The contactless power transmission system further includes a position detection unit that detects the position of the power supply device in the direction of travel of the mobile body based on the position of the mobile body and map information, and / or detects the position of the power supply device based on an analysis result of an image captured by a camera mounted on the mobile body. The control unit transmits the pairing signal when the distance to the position corresponding to the installation position of the power supply device detected by the position detection unit becomes smaller than a predetermined distance.

3. The contactless power transmission system according to claim 1, wherein: The contactless power transmission system further includes a position detection unit that detects the position of the power supply device in the direction of travel of the mobile body based on the position of the mobile body and map information, and / or detects the position of the power supply device based on an analysis result of an image captured by a camera mounted on the mobile body. The control unit transmits the pairing signal when the time taken for the moving object to reach the power supply device detected by the position detection unit becomes shorter than a predetermined time.

4. The contactless power transmission system according to claim 1, wherein: The control unit transmits a pairing signal from the power receiving device to the power supply device in a weak coupling state in which the power receiving device is coupled to the power supply device with a weak magnetic field within a predetermined range.

5. A mobile body equipped with a power receiving device that receives power from a power supply device provided on a moving path in a contactless manner, wherein: The mobile body includes a control unit that transmits a pairing signal from the power receiving device to the power supply device when a distance or time corresponding to a position of the mobile body and an installation position of the power supply device becomes less than a threshold value, and switches an operation mode of the power receiving device to a power receiving mode when a response to the pairing signal is received from the power supply device.

6. A contactless power transmission method for supplying power in a contactless manner from a power supply device provided on a moving path of a moving body to a power receiving device provided on the moving body, wherein: The power receiving device performs the following processing: When a distance or time corresponding to the position of the mobile object and the installation position of the power supply device becomes smaller than a threshold, the power receiving device transmits a pairing signal to the power supply device; as well as When a response to the pairing signal is received from the power supply device, the operation mode of the power receiving device is switched to a power receiving mode.

Images