Wireless charging system

Abstract

To provide a non-contact charging system that can prevent that non-contact charging is not started with a vehicle stopped immediately above a power transmission coil.SOLUTION: A non-contact charging system comprises: a power transmission coil installed in a parking space; an organism detection unit that detects an organism present in the vicinity of the power transmission coil; a power reception coil mounted on the vehicle; an auxiliary battery mounted on the vehicle; and a control device that executes a charging control to supply electric power transmitted in a non-contact manner to the power reception coil from the power transmission coil, to the auxiliary battery. The control device adjusts a detection range of the organism detection unit, and starts charging control if it is determined that a situation where charging control is not being executed with the vehicle stopped immediately above the power transmission coil and a situation where no organism is present within the detection range have continued for a predetermined amount of time or more.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a wireless charging system. [Background technology]

[0002] Patent document 1 discloses that in a contactless charging system having a power transmission coil installed on the ground and a power receiving coil mounted on a vehicle, power is transmitted contactlessly from the power transmission coil to the power receiving coil, and the power received by the power receiving coil is used to charge the vehicle's battery. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-109716 Summary of the Invention [Problem to be solved by the invention]

[0004] In a wireless charging system including a charging facility with a power transmitting coil and a vehicle with a power receiving coil, it is conceivable to automatically start wireless charging using a timer or the like while the vehicle is parked in a parking space where the charging facility is installed. However, there is a risk that the auxiliary battery of the vehicle will be dead by the time the scheduled charging start time arrives. If the auxiliary battery is dead, the control device installed in the vehicle will be unable to start, and charging will not begin even when the scheduled charging start time arrives.

[0005] The present invention has been made in consideration of the above circumstances, and aims to provide a contactless charging system that can prevent contactless charging from not starting when a vehicle is stopped directly above a transmission coil. [Means for solving the problem]

[0006] The present invention provides a contactless charging system comprising a transmission coil installed on the ground within a parking space, a living body detection unit that detects living bodies present near the transmission coil, a vehicle that can be parked in the parking space, a receiving coil mounted on the vehicle and receiving power transmitted contactlessly from the transmission coil, an auxiliary battery mounted on the vehicle and storing the power received by the receiving coil, and a control device that performs charging control to supply the power transmitted contactlessly from the transmission coil to the receiving coil to the auxiliary battery, wherein the control device adjusts the detection range of the living body detection unit and starts the charging control when it determines that a predetermined time or more has passed since the vehicle was stopped directly above the transmission coil and the charging control was not being performed and no living body was present within the detection range.

[0007] This configuration can prevent the initiation of contactless charging when the vehicle is stopped directly above the power transmission coil.

[0008] The predetermined time may be set to the time from when the vehicle comes to a stop until the voltage of the auxiliary battery drops to a predetermined value.

[0009] With this configuration, contactless charging can be performed before the voltage of the auxiliary battery drops below a predetermined value.

[0010] Furthermore, when adjusting the detection range, the control device may widen the detection range that is effective when the charging control is not being executed compared to the detection range when the charging control is being executed.

[0011] According to this configuration, when contactless charging is not being performed, it is possible to detect the intrusion of a living organism within a wider detection range than when contactless charging is being performed.

[0012] The control device further includes a power transmission control device that controls a power transmission device having the power transmission coil, and a vehicle control device mounted on the vehicle, the living body detection unit outputs a signal to the power transmission control device, the auxiliary battery supplies power to the vehicle control device, the vehicle control device includes a first control device that is activated when the vehicle is stopped, and a second control device that is stopped when the vehicle is stopped, the first control device periodically transmits an activation signal directly above the power transmission coil when the vehicle is stopped, and periodically activates the second control device, and the power transmission control device detects the living body Based on a signal from the detection unit, it is determined whether the period during which no living organism has entered the detection range is longer than the predetermined time, and the determination result is transmitted to the second control device. The second control device is activated in response to an activation signal from the first control device, and while activated, communicates wirelessly with the power transmission control device. When the second control device receives information from the power transmission control device indicating that the predetermined time has passed, it may determine that the charging control is not being executed when the vehicle is stopped directly above the power transmission coil and no living organism is present within the detection range for longer than the predetermined time, and start the charging control.

[0013] According to this configuration, it is possible to detect the intrusion of a person into the vicinity of the vehicle by utilizing the living body detection unit provided on the ground side.

[0014] In addition, the specified time may be set to a time shorter than the elapsed time the auxiliary battery last time ran out of power, and the elapsed time may be the time from when the vehicle stopped until when the auxiliary battery ran out of power.

[0015] With this configuration, it is determined that a predetermined time has elapsed before the auxiliary battery runs out of power, and contactless charging is performed in accordance with this determination result, thereby preventing the auxiliary battery from running out of power. [Effects of the Invention]

[0016] The present invention can prevent the initiation of contactless charging when the vehicle is stopped directly above the power transmission coil. [Brief explanation of the drawings]

[0017] [Figure 1] FIG. 1 is a schematic diagram showing a contactless charging system according to an embodiment. [Figure 2] FIG. 2 is a schematic diagram showing a state in which a vehicle is stopped directly above a power transmission coil. [Figure 3] FIG. 3 is a schematic diagram showing a high-voltage circuit of a contactless charging system. [Figure 4] FIG. 4 is a diagram for explaining a low-voltage circuit of the contactless charging system. [Figure 5] FIG. 5 is a flowchart showing a charging control flow. [Figure 6] FIG. 6 is a time chart showing a case where the auxiliary battery is charged. DETAILED DESCRIPTION OF THE INVENTION

[0018] Hereinafter, a contactless charging system according to an embodiment of the present invention will be specifically described, but the present invention is not limited to the embodiment described below.

[0019] Fig. 1 is a schematic diagram showing a contactless charging system according to an embodiment. The contactless charging system 1 is a system including a charging facility 2 and a vehicle 3. The contactless charging system 1 can contactlessly transmit power from the charging facility 2 to the vehicle 3 while the vehicle 3 is stopped. The contactless charging system 1 includes a contactless power transmission system.

[0020] The charging facility 2 is a facility that supplies power to the vehicle 3, and is installed in a parking lot of a commercial facility, a parking lot at home, or the like. The charging facility 2 includes a power transmission device 10 and an AC power source 30 that supplies power to the power transmission device 10. The AC power source 30 is a commercial power source or a household power source.

[0021] The power transmission device 10 includes a power transmission unit 12 having a power transmission coil 11, and a wall box 13 connected to an AC power source 30. The power transmission unit 12 is installed on the ground 4 within the parking space. The wall box 13 is installed near the parking space, for example, on the wall of the parking space. The power transmission unit 12 and the wall box 13 are electrically connected. Power is supplied to the power transmission unit 12 from the wall box 13. The wall box 13 is connected to an AC power source 30. Power is supplied from the AC power source 30 to the wall box 13. The wall box 13 has a power conversion unit that converts AC power supplied from the AC power source 30 into power for transmission and outputs the power to the power transmission unit 12. In the power transmission device 10, power from the AC power source 30 is supplied to the power transmission unit 12 via the power conversion unit.

[0022] The power transmitting device 10 also includes a power transmitting ECU 14 that controls the power conversion unit, and a communication device 15 that communicates with the vehicle 3. The power transmitting ECU 14 and the communication device 15 are provided in a wall box 13.

[0023] The power transmitter ECU 14 includes a processor and a memory (main storage unit). The processor includes a CPU (Central Processing Unit), a DSP (Digital Signal Processor), an FPGA (Field-Programmable Gate Array), a GPU (Graphics Processing Unit), etc. The memory includes a RAM (Random Access Memory), a ROM (Read Only Memory), etc. Signals from various sensors are input to the power transmitter ECU 14. The power transmitter ECU 14 performs various controls based on the signals input from the various sensors. For example, the power transmitter ECU 14 controls switching elements included in a power conversion unit to adjust the power to be transmitted.

[0024] The communication device 15 performs wireless communication with the vehicle 3 parked in the parking space. The communication device 15 transmits information from the power transmission ECU 14 to the vehicle 3 and receives information transmitted from the vehicle 3. The communication device 15 is capable of wireless communication using, for example, Wi-Fi (registered trademark) or wireless LAN.

[0025] The charging facility 2 also includes a living body detector 16 that detects a living body (such as a person or an animal) present near the power transmission coil 11.

[0026] The living body detection unit 16 detects the intrusion of a living body into a detection range at a predetermined distance from the power transmitting coil 11. For example, the living body detection unit 16 is configured with a Doppler sensor, a laser sensor, or the like. As shown in FIG. 2, the living body detection unit 16 is placed at the rear of the parking space so that the power transmitting unit 12 is included in its detection range. The living body detection unit 16 is a ground-side device installed in the parking lot together with the power transmitting device 10. The living body detection unit 16 is electrically connected to the wall box 13.

[0027] In the contactless charging system 1, the living object detection unit 16 performs a LOD (Living Object Detection) function. The LOD function is a function for detecting living objects. During contactless charging, a magnetic field is generated near the power transmission coil 11, and there is concern that exposure to the magnetic field may affect cardiac pacemakers. Therefore, the living object detection unit 16 outputs a detection signal to the power transmission ECU 14 when it detects that a living object has entered its detection range. The power transmission ECU 14 stops contactless charging when a detection signal is input from the living object detection unit 16 during contactless charging.

[0028] The vehicle 3 is an electrically powered vehicle that can be charged with power supplied from an external power source, and is configured as, for example, an electric vehicle (BEV) or a plug-in hybrid vehicle (PHEV). The vehicle 3 is a vehicle that can be parked in a parking space in which a power transmission coil 11 is installed. The vehicle 3 includes a power receiving device 20, a battery 22 that stores the power received by the power receiving device 20, a vehicle ECU 23 that controls the vehicle 3, and a communication device 24.

[0029] The power receiving device 20 has a power receiving coil 21. The power receiving coil 21 receives power transmitted contactlessly from the power transmitting coil 11. The power receiving device 20 supplies the power received from the power transmitting device 10 to a battery 22. The power transmitting device 10 and the battery 22 are electrically connected.

[0030] The battery 22 is an on-board battery that can be externally charged. The battery 22 is configured as a secondary battery that stores the power supplied from the power receiving device 20.

[0031] The vehicle ECU 23 is a vehicle control device mounted on the vehicle 3. The vehicle ECU 23 has a hardware configuration similar to that of the power transmission ECU 14. The vehicle ECU 23 executes various vehicle controls based on signals input from various sensors mounted on the vehicle 3 and information acquired through communication using the communication device 24. The vehicle controls include contactless charging control. The contactless charging control is charging control in which power is transmitted contactlessly from the power transmission coil 11 to the power receiving coil 21 and the power received by the power receiving coil 21 is stored in the battery 22.

[0032] The communication device 24 performs wireless communication with an external device. The communication device 24 performs wireless communication with the communication device 15 of the power transmission device 10. The communication device 24 transmits information from the vehicle 3 to the power transmission device 10 and receives information transmitted from the power transmission device 10 to the vehicle 3.

[0033] In the contactless charging system 1, contactless charging of the vehicle 3 from the power transmitter 10 is performed in a state where wireless communication is established between the vehicle 3 and the power transmitter 10. That is, in a state where the vehicle 3 and the power transmitter 10 are paired by wireless communication, power is transmitted contactlessly from the power transmitter coil 11 on the ground to the power receiver coil 21 on the vehicle side. Then, in the vehicle 3, control is performed to supply the power received by the power receiver coil 21 to the battery 22. The battery 22 includes a main battery 25 that supplies power to a traction motor and an auxiliary battery 26 that supplies power to a vehicle ECU 23. The output voltage of the main battery 25 is higher than the output voltage of the auxiliary battery 26.

[0034] 3 is a diagram showing a high-voltage circuit of a contactless charging system, which includes a high-voltage circuit included in a ground-side power transmission device 10 and a high-voltage circuit included in a vehicle 3.

[0035] The power transmitting device 10 includes a PFC circuit 17, an inverter 18, and a power transmitting coil 11.

[0036] The PFC circuit 17 improves the power factor of AC power input from the AC power supply 30, converts the AC power to DC power, and outputs it to the inverter 18. The inverter 18 converts the DC power input from the PFC circuit 17 into AC power. Each switching element of the inverter 18 is configured with an IGBT and performs switching operation in response to a control signal. The inverter 18 outputs the converted AC power to the power transmitting coil 11. The PFC circuit 17 and the inverter 18 are a power conversion unit of the power transmitting device 10 and are provided in the wall box 13.

[0037] The power transmitting coil 11 contactlessly transmits AC power supplied from the inverter 18 to the power receiving device 20. The power transmitting coil 11 forms an LC resonant circuit together with a resonant capacitor.

[0038] The power transmitting device 10 may include a filter circuit between the inverter 18 and the power transmitting coil 11. In this case, the inverter 18 outputs the converted AC power to the filter circuit. The filter circuit removes noise contained in the AC current input from the inverter 18 and supplies the AC power from which the noise has been removed to the power transmitting coil 11. The power transmitting coil 11 transmits the AC power supplied from the filter circuit to the power receiving device 20 in a wireless manner.

[0039] The power receiving device 20 includes a power receiving coil 21, a rectifier circuit 27, and a voltage sensor .

[0040] The power receiving coil 21 receives the power transmitted in a contactless manner from the power transmitting coil 11. The power receiving coil 21 forms an LC resonant circuit together with a resonant capacitor.

[0041] The rectifier circuit 27 converts the AC power input from the power receiving coil 21 into DC power and outputs it to the main battery 25. The rectifier circuit 27 is configured as a full-bridge circuit in which four diodes are fully bridge-connected as rectifier elements. A switching element is connected in parallel to each diode. Each switching element of the rectifier circuit 27 is configured by an IGBT and performs switching operation in response to a control signal. The rectifier circuit 27 supplies the converted DC power to the main battery 25.

[0042] The voltage sensor 28 is provided between the rectifier circuit 27 and the main battery 25 and detects the output voltage of the rectifier circuit 27 .

[0043] The power receiving device 20 may include a filter circuit between the power receiving coil 21 and the rectifier circuit 27. In this case, the filter circuit removes noise contained in the AC current input from the power receiving coil 21 and outputs the AC power from which the noise has been removed to the rectifier circuit 27. The rectifier circuit 27 converts the AC power input from the filter circuit into DC power and outputs it to the main battery 25.

[0044] A charging relay 40 is provided between the rectifier circuit 27 and the main battery 25. That is, the charging relay 40 is provided between the power receiving device 20 and the main battery 25. The voltage sensor 28 is provided closer to the rectifier circuit 27 than the charging relay 40.

[0045] The charging relay 40 includes a positive-side relay 41 provided on the positive power line of the main battery 25, a negative-side relay 42 provided on the negative power line of the main battery 25, and a pre-charge relay 43 connected in series with a pre-charge resistor 44. When both the positive-side relay 41 and the negative-side relay 42 are closed, the power receiving device 20 and the main battery 25 are electrically connected. When both the positive-side relay 41 and the negative-side relay 42 are open, the power receiving device 20 and the main battery 25 are electrically disconnected.

[0046] The main battery 25 is a DC power supply that supplies power to a traction motor of the vehicle 3. The traction motor is electrically connected to the main battery 25 via the PCU 29. The main battery 25 is electrically connected to the PCU 29. For example, the main battery 25 is configured by a lithium ion battery, a nickel-metal hydride battery, or the like.

[0047] The PCU 29 is a power conversion device that converts DC power from the main battery 25 into AC power. The PCU 29 includes an inverter that drives the traction motor. Each switching element of the PCU 29 is composed of an IGBT, and performs switching operation in response to a control signal. The PCU 29 supplies the converted AC power to the traction motor.

[0048] A system main relay 50 is provided between the main battery 25 and the PCU 29 .

[0049] The system main relay 50 includes a positive relay 51 connected to the positive power line of the main battery 25, and a negative relay 52 connected to the negative power line of the main battery 25. When both the positive relay 51 and the negative relay 52 are closed, the main battery 25 and the PCU 29 are electrically connected. When both the positive relay 51 and the negative relay 52 are open, the main battery 25 and the PCU 29 are electrically disconnected.

[0050] An AC charger 61, an air conditioner 62, and a DC-DC converter 63 are connected to the power line between the system main relay 50 and the PCU 29.

[0051] The auxiliary battery 26 is electrically connected to the DCDC converter 63. The DCDC converter 63 adjusts the power supplied to the auxiliary battery 26. The auxiliary battery 26 is connected to the main battery 25 via the DCDC converter 63. The DCDC converter 63 steps down the output voltage of the main battery 25 and supplies the stepped down output voltage to the auxiliary battery 26.

[0052] The auxiliary battery 26 supplies power to the vehicle ECU 23. The vehicle ECU 23 operates using the power supplied from the auxiliary battery 26. The auxiliary battery 26 is electrically connected to the power receiving device 20 via the main battery 25. Therefore, during contactless charging, the power received by the power receiving device 20 can be stored in both the main battery 25 and the auxiliary battery 26. For example, the auxiliary battery 26 is formed of a lead-acid battery. The auxiliary battery 26 is electrically connected to a low-voltage circuit including the vehicle ECU 23.

[0053] In the contactless charging system 1, the system main relay 50 is connected during charging to charge the main battery 25 with power transmitted contactlessly from the transmitting coil 11 to the receiving coil 21, and the auxiliary battery 26 is charged by operating the DCDC converter 63.

[0054] 4 is a diagram showing a low-voltage circuit of the contactless charging system 1. The control device of the contactless charging system 1 includes a vehicle ECU 23 on the vehicle side and a power transmission ECU 14 on the ground side.

[0055] The vehicle ECU 23 is configured with a plurality of control devices, including a charging integration ECU 71, a power receiving ECU 72, and a host ECU 73.

[0056] The charging integration ECU 71 is a control device that controls charging of the battery 22. The charging integration ECU 71 controls charging of the main battery 25 and also controls charging of the auxiliary battery 26. Signals from various sensors mounted on the vehicle 3 are input to the charging integration ECU 71.

[0057] A signal is input to the power receiving ECU 72 from a voltage sensor 28 provided in the power receiving device 20. The power receiving ECU 72 performs switching control of the rectifier circuit 27 based on the signal input from the voltage sensor 28. The power receiving ECU 72 performs power control to control the power supplied to the main battery 25 during contactless charging. The power receiving ECU 72 performs power control during contactless charging and controls each switching element of the rectifier circuit 27.

[0058] The power receiving ECU 72 is a control device that controls contactless charging using the power transmitting device 10 and the power receiving device 20. The power receiving ECU 72 is an ECU for power reception that controls the power receiving device 20. The power receiving ECU 72 outputs a control signal to the rectifying circuit 27 and controls each switching element of the rectifying circuit 27. The power receiving ECU 72 is also capable of transmitting and receiving information to and from the power transmitting ECU 14 on the ground side using wireless communication.

[0059] The host ECU 73 is a control device that controls the running state of the vehicle 3. The host ECU 73 is a running ECU that controls the PCU 29. The host ECU 73 executes running control that controls the drive of the running motor.

[0060] The charging integrated ECU 71, the power receiving ECU 72, and the host ECU 73 are all connected to a power line 81. The power line 81 electrically connects the vehicle ECU 23 and the auxiliary battery 26. Power from the auxiliary battery 26 is supplied to the charging integrated ECU 71, the power receiving ECU 72, and the host ECU 73 via the power line 81.

[0061] The vehicle ECU 23 also includes a first control device (ECU) that is activated when the vehicle 3 is stopped, and a second control device (ECU) that is deactivated when the vehicle 3 is stopped. In this description, the state in which the vehicle 3 is stopped means that the vehicle 3 is in a READY-OFF state, that is, the vehicle 3 is in an ignition-off state (IG-OFF state). The charging integrated ECU 71 is an ECU that is activated when the vehicle 3 is stopped. The power receiving ECU 72 is an ECU that is deactivated when the vehicle 3 is stopped. The upper ECU 73 is an ECU that is deactivated when the vehicle 3 is stopped.

[0062] Therefore, the charging integrated ECU 71 has a function of activating the power receiving ECU 72 that is stopped. The charging integrated ECU 71 is electrically connected to the power receiving ECU 72 via a direct line 82. The charging integrated ECU 71 outputs an activation signal to the power receiving ECU 72 via the direct line 82. The power receiving ECU 72 is activated when an activation signal is input from the charging integrated ECU 71 while the vehicle 3 is stopped. The activated power receiving ECU 72 can transmit and receive information to and receive information from the power transmitting ECU 14 on the ground via wireless communication while the vehicle 3 remains stopped.

[0063] Furthermore, when the power receiving ECU 72 is activated, CAN communication becomes possible between the power receiving ECU 72 and the charging integrated ECU 71. The charging integrated ECU 71 and the power receiving ECU 72 transmit signals via a local CAN bus 83. The charging integrated ECU 71 transmits a control signal to the power receiving ECU 72 via the local CAN bus 83. Furthermore, the charging integrated ECU 71 is connected to the host ECU 73 via a CAN bus 84. The host ECU 73 transmits a control signal to the charging integrated ECU 71 via the CAN bus 84.

[0064] In the vehicle ECU 23 configured as described above, when the vehicle 3 is stopped (READY-OFF state), the power receiver ECU 72 is stopped, but the charging integration ECU 71 continues to operate using power from the auxiliary battery 26. Therefore, the auxiliary battery 26 experiences a voltage drop due to natural discharge and power supply to the charging integration ECU 71. If the vehicle 3 is an electric vehicle or a plug-in hybrid vehicle, and the vehicle 3 remains in the READY-OFF state for a long period of time, the voltage of the auxiliary battery 26 drops, preventing the vehicle 3 from running or charging. To prevent this voltage drop of the auxiliary battery 26, or what is known as a dead battery, it is possible to monitor the voltage drop of the auxiliary battery 26 and charge the auxiliary battery 26 as needed. However, if the power receiver ECU 72 is configured to be constantly active in order to monitor the voltage drop of the auxiliary battery 26, power consumption by the power receiver ECU 72 will result in an accelerated voltage drop of the auxiliary battery 26. Therefore, in the wireless charging system 1, a control device on the ground side, rather than a control device on the vehicle side, is configured to indirectly monitor the voltage of the auxiliary battery 26. Since the power transmission ECU 14 on the ground side is activated using power from the AC power supply 30, the power consumption by the power transmission ECU 14 can be covered by the power supply from the AC power supply 30.

[0065] Specifically, in the contactless charging system 1, the power transmitter ECU 14 uses the LOD function and determines that the voltage of the auxiliary battery 26 has dropped when the accumulated time without biological intrusion reaches or exceeds a predetermined time. At that time, the charging integration ECU 71 and the power receiver ECU 72 perform contactless charging to drive the DC-DC converter 63 and charge the auxiliary battery 26. This prevents the auxiliary battery 26 from running out of power.

[0066] More specifically, when the power transmitter 10 is in standby mode, the living body detection unit 16 is activated, and the living body detection function is enabled. When the vehicle 3 is parked in a parking space but is not being contactlessly charged, the power transmitter 10 enters standby mode and the living body detection unit 16 enters activated mode. The power transmitter ECU 14 in standby mode can detect the intrusion of a living body into the detection range using a signal from the living body detection unit 16. Therefore, the power transmitter ECU 14 can indirectly determine whether the auxiliary battery 26 is dead by utilizing the LOD function. If the power transmitter ECU 14 determines that no human has entered the detection range for a certain period of time, it determines that the voltage of the auxiliary battery 26 has dropped. Then, in response to the power transmitter ECU 14's determination that no human has entered the detection range for a certain period of time, the power transmitter ECU 14 and the power receiver ECU 72 perform contactless charging.

[0067] The vehicle periodically activates the power receiving ECU 72, and the power receiving ECU 72 and the power transmitting ECU 14 communicate with each other to acquire information from the power transmitting ECU 14. In the vehicle 3, the charging integration ECU 71 and the verification ECU continue to operate even in the READY-OFF state (a standby state during which the user is not using the vehicle 3). The verification ECU is an ECU that determines whether the doors are unlocked or locked using the smart key and whether the sliding door is opened or closed. The charging integration ECU 71 is an ECU that detects the connection of a charging connector or a vehicle power connector to a charging inlet. Therefore, the power receiving ECU 72 can be periodically activated by an activation signal from the charging integration ECU 71. In this case, the charging integration ECU 71 determines the activation timing and periodically activates the power receiving ECU 72 by outputting an activation signal to the power receiving ECU 72 via a direct line 82. The charging integration ECU 71 activates the power receiving ECU 72, for example, once a day. The activated power receiver ECU 72 establishes wireless communication with the power transmitter 10 and exchanges information with the power receiver ECU 72. The power receiver ECU 72 acquires information from the power transmitter ECU 14 through wireless communication with the power transmitter 10.

[0068] The power receiver ECU 72 then determines whether to start contactless charging based on the information obtained from the power transmitter ECU 14. If the information obtained from the power transmitter ECU 14 indicates that no human has entered the detection range for a certain period of time, i.e., if the power transmitter ECU 14 determines that the voltage of the auxiliary battery 26 has dropped, the power receiver ECU 72 determines that contactless charging needs to start. If the power receiver ECU 72 determines that contactless charging needs to start, it starts charging control. On the other hand, if the power receiver ECU 72 determines that contactless charging does not need to start, it stops charging again.

[0069] 5 is a flowchart showing the charging control. The control shown in FIG. 5 is repeatedly executed by the power transmission ECU 14 and the vehicle ECU 23.

[0070] The power transmitter ECU 14 determines whether or not a vehicle 3 has been detected (step S1). In step S1, the power transmitter 10 determines whether or not a vehicle 3 is present in a parking space. The power transmitter ECU 14 determines that a vehicle 3 is present in a parking space if a Wi-Fi (registered trademark) connection with the vehicle 3 has been established. In other words, the power transmitter ECU 14 determines whether or not a vehicle 3 that has been paired via wireless communication is present. Alternatively, a camera may be installed in the parking lot, and the power transmitter ECU 14 may analyze images captured by the camera to determine whether or not a vehicle 3 is present.

[0071] If it is determined that the vehicle 3 is not detected (step S1: No), the power transmission ECU 14 stops the LOD function (step S2). In step S2, the living body detection unit 16 is stopped. After the process of step S2 is performed, this control routine ends.

[0072] If it is determined that the vehicle 3 is detected (step S1: Yes), the power transmitter ECU 14 enables the LOD function (step S3). In step S3, the living body detector 16 is activated.

[0073] The power transmitter ECU 14 determines whether contactless charging is being performed (step S4). In step S4, it is determined whether power is being contactlessly transmitted from the power transmitter coil 11 to the power receiver coil 21. When the power transmitter ECU 14 is configured to start contactless charging based on an instruction signal from the vehicle ECU 23, it may determine whether contactless power reception is being performed by determining whether an instruction signal is received from the vehicle ECU 23. For example, the vehicle 3 includes a contactless charging stop button as a button that can be operated by the user. In this case, when the button is operated, a stop instruction signal is output from the vehicle 3 to the power transmitter 10, and contactless charging can be stopped. The power transmitter ECU 14 follows the charging instruction from the vehicle 3, and therefore determines whether charging should be performed based on the charging instruction from the vehicle 3.

[0074] If it is determined that contactless charging is being performed (step S4: Yes), the power transmitter ECU 14 executes the first activation mode as the LOD activation mode (step S5). The LOD activation mode is an activation mode of the living body detection unit 16.

[0075] The LOD activation mode includes a first activation mode and a second activation mode. The first activation mode and the second activation mode have different detection ranges by the biological detection unit 16. The first activation mode is a mode in which the detection range is the range during normal contactless charging. The second activation mode is a mode in which the detection range is expanded to the area surrounding the vehicle 3. The detection range in the first activation mode is a detection range near the power transmitting coil 11. The detection range in the second activation mode is expanded compared to the detection range in the first activation mode and includes at least the driver's seat of the vehicle 3. The power transmitter ECU 14 can switch the LOD activation mode between the first activation mode and the second activation mode. That is, the power transmitter ECU 14 can adjust the detection range by the biological detection unit 16.

[0076] In step S5, biological intrusion is monitored in the first startup mode. Because contactless charging is being performed, the detection range in the first startup mode is applied. When the vehicle 3 is parked directly above the power transmission coil 11, if the coils are within a charging range, contactless charging is initiated under control. After the processing of step S5 is performed, this control routine ends.

[0077] If it is determined that contactless charging is not being performed (step S4: No), the power transmitter ECU 14 executes the second activation mode as the LOD activation mode (step S6). The power transmitter ECU 14 adjusts the detection range of the living body detection unit 16 depending on whether contactless charging is being performed. Because contactless charging is not being performed, the detection range of the second activation mode is applied. When adjusting the detection range, the power transmitter ECU 14 widens the detection range that is effective when charging control is not being performed compared to the detection range when charging control is being performed.

[0078] When the process of step S6 is performed, the power transmitter ECU 14 starts integrating the timer (step S7). In step S7, measurement of the integrated time starts.

[0079] When the process of step S7 is performed, the power transmitter ECU 14 determines whether or not a living organism has entered the detection range around the vehicle 3 (step S8). In step S8, it is determined whether or not a living organism is present within the detection range in the second startup mode. For example, if the user of the vehicle 3 returns to the vehicle 3, it is determined that a living organism has entered the detection range.

[0080] If it is determined that no living organism has been detected in the detection range around the vehicle 3 (step S8: No), the power transmission ECU 14 increments the accumulated time of the timer (step S9). In step S9, the accumulated time of the timer is incremented by +1.

[0081] If it is determined that a living organism has been detected in the detection range around the vehicle 3 (step S8: Yes), the power transmitter ECU 14 resets the timer (step S10). In step S10, the accumulated time of the timer is reset.

[0082] When the process of step S9 or step S10 is performed, the power transmission ECU 14 determines whether the accumulated time is equal to or longer than a predetermined time (step S11). The predetermined time is a time that is set in advance. For example, the predetermined time is set to the time from when the vehicle 3 stops until the voltage of the auxiliary battery 26 drops to a predetermined value.

[0083] If it is determined that the accumulated time is equal to or greater than the predetermined time (step S11: Yes), the power transmitter ECU 14 starts charging (step S12). In step S12, the power transmitter ECU 14 determines that the voltage of the auxiliary battery 26 has dropped, and transmits information indicating the determination result to the power receiver ECU 72. In step S12, the vehicle ECU 23 and the power transmitter ECU 14 execute contactless charging control. The vehicle ECU 23 and the power transmitter ECU 14 start charging control when they determine that a predetermined time or more has passed since the vehicle 3 stopped directly above the power transmitter coil 11, no charging control is being executed, and no living body is present within the detection range. After the processing of step S12 is performed, this control routine ends.

[0084] If it is determined that the integrated time is less than the predetermined time (step S11: No), the power transmitter ECU 14 does not start charging (step S13). After the process of step S13 is performed, this control routine ends.

[0085] Fig. 6 is a time chart for explaining a case where charging control is executed, showing a state in which the vehicle 3 is parked in a parking space.

[0086] When the vehicle 3 is parked in a parking space, the living body detection unit 16 is activated, and the LOD function is therefore enabled. In this state, contactless charging is not performed, and the voltage of the auxiliary battery 26 drops. During this time, the charging integration ECU 71 periodically activates the power receiving ECU 72. When the power receiving ECU 72 is activated, wireless communication is performed between the power receiving ECU 72 and the power transmitting ECU 14. At this time, the power receiving ECU 72 determines whether or not the information acquired from the power transmitting ECU 14 indicates that the accumulated time is equal to or greater than a predetermined time (a determination result indicating a voltage drop). If the power receiving ECU 72 determines that the information acquired from the power transmitting ECU 14 is not information indicating that the accumulated time is equal to or greater than a predetermined time, the power receiving ECU 72 stops again.

[0087] The power transmitter ECU 14 then determines that the accumulated time is equal to or greater than a predetermined time (time t1). That is, at time t1, the power transmitter ECU 14 determines that the voltage of the auxiliary battery 26 has dropped. Therefore, when the power receiver ECU 72 is activated at time t1, the power receiver ECU 72 determines that the information acquired from the power transmitter ECU 14 indicates that the accumulated time is equal to or greater than the predetermined time, and starts wireless charging. After time t1, the charging integration ECU 71 and the power receiver ECU 72 execute wireless charging control to charge the auxiliary battery 26 and the main battery 25. When charging of the auxiliary battery 26 is completed, wireless charging ends (time t2). Because the purpose of this wireless charging is to charge the auxiliary battery 26, it is completed in a shorter time than charging the main battery 25. For example, when it is determined that the voltage of the auxiliary battery 26 has increased to a predetermined value, the wireless charging ends. Note that when non-contact charging is completed, the state in which it was determined that the voltage of the auxiliary battery 26 has dropped is released.

[0088] As described above, according to the embodiment, it is possible to indirectly determine a power drop in the auxiliary battery 26 of the vehicle 3 by using the LOD function of the wireless charging system 1 and the ground-side power transmission ECU 14. This makes it possible to prevent the auxiliary battery 26 from running out of power while suppressing power consumption by the vehicle-side control device.

[0089] The biometric detector 16 may be installed not only on the ground side but also on the vehicle side. When the biometric detector is mounted on the vehicle 3, it is configured by, for example, an on-board camera. The on-board camera biometric detector performs the LOD function with the periphery of the vehicle 3 as its detection range. In this case, the on-board biometric detector activates the LOD function when the vehicle 3 is stopped, and is capable of outputting a signal to the power transmission ECU 14 on the ground side via wireless communication.

[0090] Furthermore, the power transmitting device 10 does not necessarily have to include the wall box 13. The power transmitting device 10 may be one in which the power transmitting ECU 14 and the communication device 15 are installed on the ground 4 together with the power transmitting unit 12.

[0091] Furthermore, the charging facility 2 may be installed in a parking lot having a plurality of parking spaces. In this case, a power transmitting device 10 is installed for each parking space. [Explanation of symbols]

[0092] 1. Wireless charging system 2 Charging equipment 3 vehicles 4 ground 10 Power transmission equipment 11. Transmission coil 12 Power Transmission Unit 13 Wall Box 14 Power Transmission ECU 15. Communications equipment 16. Biodetection unit 17 PFC circuit 18 Inverter 20 Power receiving device 21 Receiving coil 22 Battery 23 Vehicle ECU 24 Communication equipment 25 Main battery 26 Auxiliary battery 27 Rectifier circuit 30 AC power supply 40 Charging relay

Claims

1. a power transmission coil installed on the ground within the parking space; a living body detection unit that detects a living body present near the power transmitting coil; a vehicle that can be parked in the parking space; a power receiving coil mounted on the vehicle and receiving the power transmitted from the power transmitting coil in a wireless manner; an auxiliary battery mounted on the vehicle and configured to store the power received by the power receiving coil; a control device that executes charging control to supply the auxiliary battery with the power that is contactlessly transmitted from the power transmitting coil to the power receiving coil; A contactless charging system comprising: the control device adjusts the detection range of the living body detection unit, and starts the charging control when it determines that a predetermined time or more has passed since the vehicle is stopped directly above the power transmission coil and the charging control is not being executed and no living body is present within the detection range; The predetermined time is set to the time from when the vehicle stops until the voltage of the auxiliary battery drops to a predetermined value. A non-contact charging system characterized by the above.

2. When adjusting the detection range, the control device widens the detection range that is effective when the charging control is not being executed compared to the detection range when the charging control is being executed.

2. The contactless charging system according to claim 1.

3. The control device a power transmission control device that controls a power transmission device having the power transmission coil; a vehicle control device mounted on the vehicle, the living body detection unit outputs a signal to the power transmission control device, the auxiliary battery supplies power to the vehicle control device; The vehicle control device includes: a first control device that is activated while the vehicle is stopped; a second control device that is stopped when the vehicle is stopped, the first control device periodically transmits an activation signal while the vehicle is stopped directly above the power transmission coil, thereby periodically activating the second control device; the power transmission control device determines whether a period during which no living organism has entered the detection range is equal to or longer than the predetermined period based on the signal from the living organism detection unit, and transmits the determination result to the second control device; The second control device is the power transmission control device is activated in response to an activation signal from the first control device, and wirelessly communicates with the power transmission control device during activation; When information indicating that the predetermined time has elapsed is acquired from the power transmission control device, the charging control device determines that the predetermined time has elapsed while the vehicle is stopped directly above the power transmission coil and the charging control is not being executed and no living body is present within the detection range, and starts the charging control.

3. The non-contact charging system according to claim 2.

4. The predetermined time is set to a time shorter than the time that elapsed since the previous time the auxiliary battery ran out of power, The elapsed time is the time from when the vehicle stops to when the auxiliary battery runs out of power.

4. The contactless charging system according to claim 1, wherein the charging device is a power supply.

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