Control devices, charging systems, vehicles

The control device addresses the issue of outlet and power path deterioration in charging systems by disconnecting one wire during inspections, using C-contact relays and voltage sensors to accurately assess relay states, ensuring reliable and less deteriorative system checks.

JP2026070844APending Publication Date: 2026-04-28TOYOTA JIDOSHA KK
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Patent Information

Authority / Receiving Office
JP · JP
Patent Type
Applications
Current Assignee / Owner
TOYOTA JIDOSHA KK
Filing Date
2024-10-16
Publication Date
2026-04-28

AI Technical Summary

Technical Problem

The existing inspection methods for charging systems, such as those described in Japanese Patent Application Laid-Open No. 2021-112017, apply voltage to the vehicle interior outlet during inspections, which can accelerate the deterioration of the outlet and power paths, and do not accurately determine the state of the power path switching function.

Method used

A control device is implemented to perform inspections by disconnecting one wire of the power circuit from the energy storage device during voltage application, allowing for accurate determination of switching device functionality while minimizing deterioration. This device includes a switching device with C-contact relays and voltage sensors to detect voltage changes, enabling precise assessment of relay states.

Benefits of technology

The solution allows for accurate grasping of the charging system's state, including relay malfunctions, while reducing deterioration, enabling more frequent inspections and preventing control failures by prohibiting inappropriate power controls based on relay states.

✦ Generated by Eureka AI based on patent content.

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Abstract

The system's condition (for example, whether or not there is a malfunction in the power switching function) is accurately assessed while minimizing deterioration of the charging system due to inspection. [Solution] The control device performs a first inspection and a second inspection. In the first inspection, when a voltage is applied between the first and second wires constituting the first power line, the control device controls the switching device so that the first wire is electrically connected to the energy storage device and the second wire is disconnected from the energy storage device, and determines whether the switching device is faulty based on the voltage applied to the energy storage device side of the switching device. If the control device determines in the first inspection that the charger is not faulty, in the second inspection, it controls the switching device so that the second wire is electrically connected to the energy storage device and the first wire is disconnected from the energy storage device, and determines whether the switching device is faulty based on the voltage applied to the energy storage device side of the switching device.
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Description

Technical Field

[0001] The present disclosure relates to a control device, a charging system, and a vehicle.

Background Art

[0002] Japanese Patent Application Laid-Open No. 2021-112017 (Patent Document 1) discloses a charging system including a bidirectional charger, an inlet, a vehicle interior outlet, and a C-contact relay that switches between a first power path on the inlet side and a second power path on the vehicle interior outlet side. This charging system performs an inspection of the C-contact relay. In this inspection, the C-contact relay and the bidirectional charger are controlled such that the C-contact relay connects the bidirectional charger to the vehicle interior outlet and the bidirectional charger outputs a voltage of less than 100 V to the vehicle interior outlet. Then, if a voltage is detected at the inlet, it is determined that the C-contact relay is welded, and if no voltage is detected at the inlet, it is determined that the C-contact relay is normal. Note that the bidirectional charger described in Patent Document 1 functions as a bidirectional power converter.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the inspection method described in Patent Document 1, the bidirectional power converter outputs a voltage for the inspection of the C-contact relay. Then, while the C-contact relay is normal, a voltage is applied to the vehicle interior outlet and the second power path every time the inspection is performed. Such application of the voltage may accelerate the deterioration of the vehicle interior outlet and the second power path.

[0005] This disclosure was made to solve the above-mentioned problems, and its purpose is to accurately grasp the state of the charging system (for example, whether or not there is a malfunction in the function of switching the power path) while suppressing deterioration of the charging system due to inspection. [Means for solving the problem]

[0006] According to the first aspect of this disclosure, the following control device is provided. (Paragraph 1) The control device is configured to control a charger configured to be electrically connectable to each of the first power line, the second power line, and the energy storage device. The charger includes a switching device configured to electrically connect either the first power line or the second power line to the energy storage device. The control device is configured to control the charger so that the energy storage device and the first power line are electrically connected via the charger, and the charger charges the energy storage device using power supplied from the first power line. The control device is configured to control the charger so that the energy storage device and the second power line are electrically connected via the charger, and the charger supplies power to the second power line using power supplied from the energy storage device. The control device is configured to perform a first test and a second test. In the first test, the control device controls the switching device so that when a voltage is applied between the first and second wires constituting the first power line, the first wire is electrically connected to the energy storage device and the second wire is disconnected from the energy storage device, and determines whether the switching device is faulty based on the voltage applied on the energy storage device side of the switching device. If the control device determines in the first inspection that the charger is not faulty, in the second inspection it controls the switching device so that the second wire is electrically connected to the energy storage device and the first wire is disconnected from the energy storage device, and determines whether the switching device is faulty based on the voltage applied to the energy storage device side of the switching device.

[0007] As described above, in each of the first and second inspections, the control device controls the switching device to disconnect one of the first and second wires constituting the first power circuit from the energy storage device. Therefore, if the switching device is functioning correctly, the voltage from the first power circuit will not be applied to the energy storage device side of the switching device. Thus, deterioration of the charging system due to inspection is suppressed. Furthermore, by suppressing deterioration of the charging system due to inspection, it becomes easier to perform inspections at a higher frequency.

[0008] On the other hand, in each of the first and second tests described above, if the voltage from the first power line is applied to the energy storage device side rather than the switching device side, it is considered that the switching device is not functioning properly. Therefore, the control device makes it possible to accurately grasp the state of the charging system (especially whether or not the switching device is malfunctioning). Furthermore, by performing the first and second tests, the control device can confirm whether or not the switching device is being correctly controlled for two patterns of operation of the switching device.

[0009] According to a second aspect of this disclosure, the following charging system is provided: (Section 2) The charging system comprises the control device described in Section 1 and a charger controlled by the control device. The charger further comprises a power conversion circuit located between the switching device and the energy storage device, and a first voltage sensor that detects a first voltage applied between the switching device and the power conversion circuit. The power conversion circuit is configured to convert DC power supplied from the energy storage device into AC power and output it to the switching device, and to convert AC power supplied from the first power line into DC power and output it to the energy storage device. The first voltage sensor is configured to output the detected value of the first voltage to the control device.

[0010] According to the above configuration, the charging system can easily perform both charging of the energy storage device using AC power and supplying power to the first or second power line using the power (DC power) of the energy storage device. Furthermore, by using the detected value of the first voltage sensor, the control device can easily perform the aforementioned first and second inspections appropriately.

[0011] (Clause 3) In the charging system described in paragraph 2, the switching device includes a first C contact relay and a second C contact relay. Each of the first C contact relay and the second C contact relay is configured to disconnect the power conversion circuit from the other power path when the power conversion circuit is connected to one of the first power path and the second power path.

[0012] The above-described first C-contact relay and second C-contact relay enable the switching device to appropriately switch between the first power path and the second power path.

[0013] (Article 4) In the charging system described in Article 3, the control device is configured to determine that the second C contact relay is welded when, in the first inspection, the first voltage does not drop by controlling the switching device so that the first C contact relay connects the power conversion circuit to the first power circuit and the second C contact relay connects the power conversion circuit to the second power circuit when a voltage is applied from the first power circuit to the power conversion circuit.

[0014] With the above configuration, the control device can more easily determine the state of the second C contact relay through the first inspection. Specifically, if the first inspection determines that the second C contact relay is welded, it is considered that the second C contact relay is welded to the first power line side.

[0015] (Article 5) In the charging system described in Article 4, the control device is configured to determine that the first C contact relay is welded when the first voltage rises in the second inspection by controlling the switching device so that the first C contact relay connects the power conversion circuit to the second power line and the second C contact relay connects the power conversion circuit to the first power line.

[0016] With the above configuration, the control device can more easily determine the state of the first C contact relay through the second inspection. Specifically, if the second inspection determines that the first C contact relay is welded, it is considered that the first C contact relay is welded to the first power line side.

[0017] According to the third aspect of this disclosure, the following vehicles are provided: (Article 6) The vehicle is equipped with a charging system as described in any one of paragraphs 2 to 5. The vehicle further includes an inlet electrically connected to a first power line and an outlet electrically connected to a second power line. The vehicle is configured to perform AC charging, which converts alternating current power supplied from outside the vehicle to the inlet into direct current power using a charger, and supplies the converted direct current power to a power storage device. The control device is configured to start the first inspection when AC charging is completed.

[0018] In AC charging, voltage is applied between the first and second wires that constitute the first power circuit. In the above vehicle, this voltage is used to perform an inspection when AC charging ends. Therefore, it is not necessary to apply voltage solely for the purpose of inspection.

[0019] According to the fourth aspect of this disclosure, the following vehicles are provided: (Section 7) The vehicle is equipped with the charging system described in Section 5. The vehicle is configured to be able to run using power output from the energy storage device. The charger further includes a second voltage sensor that detects a second voltage applied to a first power line and a third voltage sensor that detects a third voltage applied to the second power line. The second voltage sensor and the third voltage sensor are configured to output the detected values ​​of the second and third voltages, respectively, to the control device. The control device is configured to perform a third inspection in which, when the first C contact relay connects a power conversion circuit to the second power line, and the second C contact relay connects a power conversion circuit to the first power line, and the power conversion circuit converts the DC power supplied from the energy storage device into AC power and outputs it to the switching device, the control device determines that the first C contact relay is welded if the second voltage rises, and determines that the second C contact relay is welded if the third voltage rises. The control device is configured to perform a fourth inspection in which, if the third inspection determines that neither the first C contact relay nor the second C contact relay is welded, the control device further performs a fourth inspection. The control device is configured such that, in the fourth inspection, when the first C-contact relay connects the power conversion circuit to the first power line, the second C-contact relay connects the power conversion circuit to the second power line, and the power conversion circuit converts the DC power supplied from the energy storage device into AC power and outputs it to the switching device, the control device determines that the second C-contact relay is welded if the second voltage rises, and determines that the first C-contact relay is welded if the third voltage rises. The control device is configured to start the third inspection when the vehicle starts running and / or while it is running.

[0020] Typically, the inlet is used while parked. Also, while the vehicle is in motion (especially at startup), the user is unlikely to use the outlet to prevent the battery from running out. Therefore, both the inlet and the outlet are likely to be disconnected when the vehicle starts up and while it is in motion. With the above configuration, if the charger does not operate properly in the third or fourth test, the voltage applied to the inlet or outlet is less likely to damage external devices connected to the inlet or outlet (e.g., power supply equipment connected to the inlet, or a power load connected to the outlet). Furthermore, with the above configuration, the control unit can more easily determine the state of the first C contact relay and the second C contact relay through the third and fourth tests.

[0021] (Clause 8) In the vehicle described in paragraph 7, the control device is configured to prohibit the first control for supplying power from the first power line to the energy storage device in each case where the second C contact relay is determined to be welded in the third inspection and where the first C contact relay is determined to be welded in the fourth inspection. The control device is configured to prohibit the second control for supplying power from the energy storage device to the second power line in each case where the second C contact relay is determined to be welded in the first inspection, where the first C contact relay is determined to be welded in the second inspection, where the first C contact relay is determined to be welded in the third inspection and where the second C contact relay is determined to be welded in the fourth inspection.

[0022] If the third inspection determines that the second C contact relay is welded, it is likely that the second C contact relay is welded to the second power line side. If the fourth inspection determines that the first C contact relay is welded, it is likely that the first C contact relay is welded to the second power line side. Therefore, by prohibiting the first control (charging control of the energy storage device using the first power line) as described above, control malfunctions can be prevented.

[0023] Also, when it is determined in the first inspection that the second C-contact relay is welded, it is considered that the second C-contact relay is welded to the first power path side. When it is determined in the second inspection that the first C-contact relay is welded, it is considered that the first C-contact relay is welded to the first power path side. When it is determined in the third inspection that the first C-contact relay is welded, it is considered that the first C-contact relay is welded to the first power path side. When it is determined in the fourth inspection that the second C-contact relay is welded, it is considered that the second C-contact relay is welded to the first power path side. Therefore, by prohibiting the second control (discharge control of the power storage device using the second power path) as described above, control failures can be prevented in advance.

[0024] Thus, according to the first to fourth inspections, it becomes easier for the control device to accurately grasp the states of each of the first C-contact relay and the second C-contact relay. For this reason, the control device can prohibit a predetermined control (for example, a control that does not match the grasped state) based on the grasped state.

Effect of the Invention

[0025] According to the present disclosure, it becomes possible to accurately grasp the state of the charging system (for example, the presence or absence of a failure in the function of switching the power path) while suppressing the deterioration of the charging system due to inspections.

Brief Description of the Drawings

[0026] [Figure 1] It is a diagram showing a schematic configuration of a vehicle according to an embodiment of the present disclosure. [Figure 2] It is a flowchart showing first inspection control according to an embodiment of the present disclosure. [Figure 3] It is a diagram showing an example of the state of the charger determined to be normal in the control of FIG. 2. [Figure 4] It is a diagram showing a first example of the state of the charger determined to be faulty in the control of FIG. 2. [Figure 5] It is a diagram showing a second example of the state of the charger determined to be faulty in the control of FIG. 2. [Figure 6]This figure shows a third example of a charger state that is determined to be a failure by the control system in Figure 2. [Figure 7] This figure shows a fourth example of a charger state that is determined to be a failure by the control system in Figure 2. [Figure 8] This figure shows the fifth example of a charger state that is determined to be a malfunction by the control system in Figure 2. [Figure 9] This is a flowchart showing the second inspection control according to an embodiment of the present disclosure. [Figure 10] This figure shows an example of a charger state that is determined to be normal by the control system in Figure 9. [Figure 11] This figure shows the first example of a charger state that is determined to be a malfunction by the control system in Figure 9. [Figure 12] This figure shows a second example of a charger state that is determined to be a malfunction by the control system in Figure 9. [Figure 13] This is a flowchart showing the control prohibition process according to the embodiment of this disclosure. [Figure 14] This figure shows a modified example of the vehicle configuration shown in Figure 1. [Modes for carrying out the invention]

[0027] The embodiments of this disclosure will be described in detail below with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and their descriptions will not be repeated.

[0028] Figure 1 is a diagram showing the configuration of vehicle 1 according to this embodiment. Referring to Figure 1, vehicle 1 is, for example, an electric vehicle (BEV) without an internal combustion engine. However, it is not limited to this, and vehicle 1 may be a PHEV (plug-in hybrid vehicle) equipped with an internal combustion engine, or another electric vehicle (xEV).

[0029] Vehicle 1 is equipped with an AC inlet 11, an outlet 12, a DC inlet 21, a relay 22, a charger 100, a battery 30, an SMR 31, an inverter 32, an MG (Motor Generator) 33, an ECU 50, and an HMI (Human Machine Interface) 80. The charger 100 functions as an OBC (On Board Charger). The ECU 50 corresponds to an example of a "control device" according to this disclosure. "ECU" means Electronic Control Unit. "SMR" means System Main Relay.

[0030] The charger 100 comprises a housing 101 and ports 102, 103, and 104 provided on the housing 101. The charger 100 is configured to be electrically connectable to each of the power lines PL1 to PL3 via ports 102, 103, and 104. The battery 30 is connected to power line PL1. The charger 100 is configured to be detachable at each port. This makes it easy to replace the charger 100.

[0031] Port 102 is connected to the connector for power line PL2, which connects the AC inlet 11 and the charger 100. Power line PL2 includes a first-polarity wire PL2a and a second-polarity wire PL2b. Power line PL2 is electrically connected to both the AC inlet 11 and the charger 100. Port 103 is connected to the connector for power line PL3, which connects the outlet 12 and the charger 100. Power line PL3 includes a first-polarity wire PL3a and a second-polarity wire PL3b. Power line PL3 is electrically connected to both the outlet 12 and the charger 100. Port 104 is connected to the connector for power line PL5, which connects power line PL1 and the charger 100. Power line PL5 includes a first-polarity wire PL5a and a second-polarity wire PL5b. Power line PL5 is electrically connected to both power line PL1 and the charger 100. The power line PL1 includes a first-polarity wire PL1a and a second-polarity wire PL1b. The power line PL1 is electrically connected to both the battery 30 and the power line PL5. The battery 30 outputs the drive power of the vehicle 1 to the power line PL1. The first and second polarities are opposite polarities. In this embodiment, the first polarity is the negative terminal and the second polarity is the positive terminal. However, it is not limited to this, and the first polarity may be changed to the positive terminal and the second polarity to the negative terminal.

[0032] Power path PL1 is the power path from battery 30 to inverter 32. SMR31 includes a pair of relays (e.g., electromagnetic mechanical relays) provided on wires PL1a and PL1b and is configured to switch the connection / disconnection of wires PL1a and PL1b. Power path PL4 is the power path from DC inlet 21 to power path PL1. Power path PL4 includes wire PL4a of first polarity and wire PL4b of second polarity. Power path PL4 is electrically connected to DC inlet 21 and power path PL1, respectively. Relay 22 includes a pair of relays (e.g., electromagnetic mechanical relays) provided on wires PL4a and PL4b and is configured to switch the connection / disconnection of wires PL4a and PL4b. Wire PL1a is connected to wires PL4a and PL5a, respectively, on the inverter 32 side of SMR31. Wire PL1b is connected to wires PL4b and PL5b respectively on the inverter 32 side of SMR31.

[0033] Vehicle 1 is configured to run using power output from battery 30. Specifically, MG33 functions as a drive motor, and inverter 32 functions as the drive circuit for MG33. Power is supplied from battery 30 to inverter 32 through wires PL1a and PL1b. Inverter 32 drives MG33 using power output from battery 30. MG33 converts power into torque, which rotates the drive wheels of vehicle 1. MG33 regenerates power, for example, when vehicle 1 is decelerating, and charges battery 30.

[0034] Vehicle 1 is configured to perform AC charging by converting alternating current power supplied from outside the vehicle to the AC inlet 11 into direct current power using a charger 100, and supplying the converted direct current power to the battery 30. Specifically, the AC inlet 11 is equipped with a connector locking device. When the connector of the charging cable of the AC power supply equipment outside the vehicle (hereinafter referred to as "AC connector") is connected to the AC inlet 11, the connector locking device locks the AC connector (connector lock). This prevents the AC connector from being removed. After AC charging is completed, the lock on the AC connector is released (unlocked) by the connector locking device. This allows the AC connector to be removed. The charger 100 also includes a power conversion circuit 110 and a switching device 120. In this embodiment, the power conversion circuit 110 functions as a bidirectional power converter (for example, a bidirectional converter). The switching device 120 is located at the point where the wires electrically connected to power line PL2 (wires PL11a, PL11b), the wires electrically connected to power line PL3 (wires PL12a, PL12b), and the wires electrically connected to power conversion circuit 110 (wires PL13a, PL13b) converge. The switching device 120 is configured to switch between connecting and disconnecting power line PL2 and power conversion circuit 110. When the switching device 120 has selected power line PL2, power line PL2 and power conversion circuit 110 are electrically connected, and power line PL3 is disconnected from power conversion circuit 110. AC charging is performed in this state.

[0035] For example, after the AC connector is connected to the AC inlet 11 and the connector lock is performed, a predetermined test (pre-power supply test) is performed. If no abnormality is found in the pre-power supply test, AC power is supplied from the AC power supply equipment to the AC inlet 11. Then, the power conversion circuit 110 converts the AC power input from the AC inlet 11 to port 102 into DC power having a predetermined voltage (for example, the voltage corresponding to the battery 30), and outputs the converted DC power to port 104. As a result, DC power is output from the charger 100 to the battery 30, and the battery 30 is charged.

[0036] Vehicle 1 is configured to perform DC charging, which supplies DC power supplied to Vehicle 1 from outside the vehicle to the battery 30 without passing through the charger 100. Specifically, the DC inlet 21 is equipped with a connector locking device. When the connector of the charging cable of the DC power supply equipment outside the vehicle (hereinafter referred to as "DC connector") is connected to the DC inlet 21, the connector locking device locks the DC connector (connector lock). This prevents the DC connector from being removed. After DC charging is completed, the lock on the DC connector is released (unlocked) by the connector locking device. This allows the DC connector to be removed.

[0037] For example, after the DC connector is connected to the DC inlet 21 and the connector lock is performed, a predetermined test (pre-power supply test) is performed. If no abnormality is found in the pre-power supply test, DC power is supplied from the DC power supply equipment to the DC inlet 21. Then, when the ECU 50 sets the relay 22 to the connected state (closed state), DC power is supplied from the DC inlet 21 to the battery 30 through the power line PL4, and the battery 30 is charged.

[0038] In the following, AC charging and DC charging may be collectively referred to as "external charging." The power supply equipment used for external charging may be an EVSE (Electric Vehicle Supply Equipment) electrically connected to the power grid.

[0039] Vehicle 1 is configured to perform external power supply by converting DC power supplied from battery 30 to charger 100 into AC power by charger 100, and supplying the converted AC power to outlet 12. Specifically, the switching device 120 is configured to switch the connection / disconnection of power path PL3 and power conversion circuit 110. When the switching device 120 has selected power path PL3, power path PL3 and power conversion circuit 110 are electrically connected, and power path PL2 is disconnected from power conversion circuit 110. External power supply is performed in this state. The power conversion circuit 110 converts the DC power input from battery 30 to port 104 into AC power having a predetermined voltage (for example, the voltage corresponding to outlet 12), and outputs the converted AC power to port 103. As a result, AC power is output from charger 100 to outlet 12, and outlet 12 becomes usable. The user can supply power to the power load by connecting the power load to outlet 12, thereby supplying power output from outlet 12 during external power supply to the power load. Examples of power loads include lighting equipment, air conditioning equipment, cooking appliances, refrigerators, and information processing equipment. The outlet 12 may be installed inside the vehicle 1. The number of outlets 12 is not limited to one, but may be multiple. The ECU 50 may supply external power in response to a user request.

[0040] Relay 22, SMR 31, inverter 32, and charger 100 are controlled by ECU 50. SMR 31 is kept connected (closed) while vehicle 1 is running, externally charging, and externally supplying power. ECU 50 connects relay 22 when DC charging starts and disconnects relay 22 when DC charging is finished.

[0041] As the battery 30, a known vehicle energy storage device (e.g., lithium-ion secondary battery, nickel-metal hydride secondary battery, or sodium-ion secondary battery) can be used. The type of secondary battery may be either a liquid-type secondary battery or an all-solid-state secondary battery. Multiple secondary batteries may form a battery pack. An electric double-layer capacitor may be used instead of a secondary battery. The battery 30 corresponds to an example of an "energy storage device" according to this disclosure.

[0042] Inside the charger 100, in addition to the aforementioned power conversion circuit 110 and switching device 120, there are further wires PL11a, PL12a, PL13a, PL14a of the first polarity, wires PL11b, PL12b, PL13b, PL14b of the second polarity, and voltage sensors Sa, Sb, Sc.

[0043] The switching device 120 is configured to switch between power lines PL2 and PL3. Specifically, the switching device 120 includes a first-polarity relay C2 and a second-polarity relay C1. Each of relays C1 and C2 is a C-contact relay. Each of relays C1 and C2 is configured to disconnect the power conversion circuit 110 from one of the power lines PL2 and PL3 when the power conversion circuit 110 is connected to the other power line, as will be described below. In this embodiment, relays C1 and C2 correspond to examples of the "first C-contact relay" and "second C-contact relay" according to this disclosure, respectively.

[0044] Wire PL11a is electrically connected to wire PL2a via port 102. One end of relay C2 is connected to power conversion circuit 110 via wire PL13a. The other end of relay C2 is connected to only one of wires PL11a and PL12a, selected by ECU 50. Wire PL12a is electrically connected to wire PL3a via port 103. Power conversion circuit 110 is electrically connected to wire PL2a or PL3a of the corresponding power line via wire PL11a or PL12a connected by relay C2. On the other hand, power conversion circuit 110 is disconnected from wire PL3a or PL2a of the power line not connected by relay C2. Hereinafter, the connection of relay C2 to wire PL11a will be referred to as "C2 external connection". Also, the connection of relay C2 to wire PL12a will be referred to as "C2 internal connection".

[0045] Wire PL11b is electrically connected to wire PL2b via port 102. One end of relay C1 is connected to power conversion circuit 110 via wire PL13b. The other end of relay C1 is connected to only one of wires PL11b and PL12b, selected by ECU 50. Wire PL12b is electrically connected to wire PL3b via port 103. Power conversion circuit 110 is electrically connected to wire PL2b or PL3b of the corresponding power line via wire PL11b or PL12b connected by relay C1. On the other hand, power conversion circuit 110 is disconnected from wire PL3b or PL2b of the power line not connected by relay C1. Hereinafter, the connection of relay C1 to wire PL11b will be referred to as "C1 external connection". Also, the connection of relay C1 to wire PL12b will be referred to as "C1 internal connection".

[0046] The power conversion circuit 110 is located between the switching device 120 and port 104. One end of the power conversion circuit 110 is connected to the switching device 120 via wires PL13a and PL13b. The other end of the power conversion circuit 110 is connected to port 104 via wires PL14a and PL14b. In addition, wires PL14a and PL14b are electrically connected to wires PL5a and PL5b, respectively, via port 104.

[0047] When the switching device 120 selects power line PL2, "external connection of C1" and "external connection of C2" are performed. As a result, the power conversion circuit 110 is electrically connected to the respective wires PL2a and PL2b that constitute power line PL2. Hereinafter, this state will be referred to as the "first switching state".

[0048] When the switching device 120 selects power line PL3, "C1 central connection" and "C2 central connection" are performed. As a result, the power conversion circuit 110 is electrically connected to each of the wires PL3a and PL3b that constitute power line PL3. Hereinafter, this state will be referred to as the "second switching state".

[0049] The power conversion circuit 110 is configured to perform DC (direct current) / AC (alternating current) conversion bidirectionally. The power conversion circuit 110 may include an inverter and an isolation transformer. The power conversion circuit 110 is controlled to one of three states: a stopped state in which it does not output power, a DC output state in which it outputs DC power to port 104, or an AC output state in which it outputs AC power to the switching device 120. During AC charging, the power conversion circuit 110 is in the DC output state and the switching device 120 is in the first switching state. Specifically, the AC power supplied from the AC inlet 11 to port 102 is input to the power conversion circuit 110 through the switching device 120 in the first switching state, and the power conversion circuit 110 converts that AC power into DC power and outputs it to the battery 30. During external power supply, the power conversion circuit 110 is in the AC output state and the switching device 120 is in the second switching state. Specifically, the DC power supplied from the battery 30 to the port 104 is input to the power conversion circuit 110, which converts the DC power into AC power and outputs it to the switching device 120. The AC power output from the power conversion circuit 110 is supplied to the outlet 12 through the switching device 120 in the second switching state.

[0050] As described above, the switching device 120 is configured to electrically connect either power path PL2 or power path PL3 to the battery 30 (power conversion circuit 110). However, in the inspection of the charger 100 described later, the switching device 120 is controlled to be in a state that is neither the first switching state nor the second switching state. In the inspection, the detection values ​​of the voltage sensors Sa, Sb, and Sc, described below, are used.

[0051] The voltage sensor Sb is located between the switching device 120 and the power conversion circuit 110. The voltage sensor Sb detects the voltage applied between the wires PL13a and PL13b (hereinafter referred to as "Vb"). Vb represents the first voltage applied between the switching device 120 and the power conversion circuit 110.

[0052] The voltage sensor Sa is located between port 102 and the switching device 120. The voltage sensor Sa detects the voltage applied between wires PL11a and PL11b (hereinafter referred to as "Va"). Va represents the second voltage applied between wires PL2a and PL2b in the power line PL2.

[0053] The voltage sensor Sc is located between port 103 and the switching device 120. The voltage sensor Sc detects the voltage applied between wires PL12a and PL12b (hereinafter referred to as "Vc"). Vc represents the third voltage applied between wires PL3a and PL3b in the power line PL3.

[0054] The voltage sensors Sa, Sb, and Sc are configured to output Va, Vb, and Vc, respectively, to the ECU 50. The voltage sensors Sb, Sa, and Sc correspond to examples of the "first voltage sensor," "second voltage sensor," and "third voltage sensor" as described herein.

[0055] The ECU50 comprises a processor and a memory device. Various processes are executed by the processor executing programs stored in the memory device. However, these processes may be performed solely by hardware (electronic circuits) without the use of software.

[0056] The HMI80 includes input devices and notification devices. Examples of notification devices include displays, speakers, and lamps. The HMI80 may also include a touch panel display. Through the HMI80, the user may request processing from the ECU50 (for example, initiating control related to the driving of vehicle 1, AC charging, DC charging, or external power supply) or input parameter values ​​to the ECU50.

[0057] In this embodiment, when vehicle 1 changes from a parked state to a driving state, the ECU 50 executes the inspection control shown in Figure 2. Figure 2 is a flowchart of the first inspection control according to this embodiment. In the flowchart, "S" means step.

[0058] For example, when the control system (vehicle system) of vehicle 1 is stopped (including sleep mode), if the user requests vehicle 1 to start the vehicle system via HMI 80, the vehicle system (including ECU 50) starts up, and the started ECU 50 controls the switching device 120 to the second switching state. Furthermore, if the user requests the ECU 50 to start driving via HMI 80, the ECU 50 connects the SMR 31 so that the voltage of the battery 30 is applied to the inverter 32. This makes it possible for vehicle 1 to be driven by the MG 33. Subsequently, the ECU 50 starts the processing flow F1 shown in Figure 2. At the start of processing flow F1, if the charger 100 is functioning normally, the power conversion circuit 110 is in a stopped state, and the switching device 120 is in the second switching state ("C1 connected" and "C2 connected").

[0059] In processing flow F1, ECU 50 drives relay C2 to "C2 external connection" in S61 and instructs power conversion circuit 110 to supply AC power. The control of relay C2 and the control of power conversion circuit 110 may be performed simultaneously or sequentially. ECU 50 sends control commands to power conversion circuit 110 so that it enters an AC output state in a predetermined pattern (see Figure 3 described later).

[0060] In S62, the ECU 50 determines whether Vb increased as a result of the processing in S61. If Vb did not increase (NO in S62), the ECU 50 executes the processes in S63 and S77, and then the processing flow F1 (inspection control) ends.

[0061] In the S63, the ECU 50 records diagnostic information. Diagnostic information is information used in the vehicle's self-diagnosis process to determine whether the vehicle is operating normally, and will be referred to as "diagnostic" below. In the S63, the ECU 50 stores diagnostic D1 in its memory. Diagnostic D1 is information indicating that the power conversion circuit 110 is faulty. In this way, the ECU 50 determines that the power conversion circuit 110 is faulty if Vb does not rise even when the power conversion circuit 110 controls the charger 100 to convert the DC power supplied from the battery 30 into AC power and output it to the switching device 120. With this configuration, the ECU 50 can more easily grasp the status of the charging system.

[0062] In the following step S77, the ECU 50 controls the HMI 80 so that the user is notified of an abnormality. The HMI 80 may notify the user of the abnormality by illuminating a lamp. The HMI 80 may display a message indicating that an abnormality has occurred in the charger 100. The HMI 80 may also display a message prompting the user to replace the faulty charger 100. The HMI 80 may display on a map the location of a place where the charger 100 can be replaced (for example, the nearest dealer) and the route from the vehicle 1's current location to that location, and guide the user to that location.

[0063] If Vb increases as a result of the process in S61 (YES in S62), ECU50 determines in S64 whether Va has increased as a result of the process in S61. If Va has increased (YES in S64), ECU50 executes processes S65 and S77. In S65, ECU50 saves diagnostic D4 to its storage device. Diagnostic D4 is information indicating that relay C1 is welded in the "C1 external connection" state. After that, the process in S77 described above is executed, and the process flow F1 (inspection control) ends.

[0064] If Va does not increase as a result of the process in S61 (NO in S64), the ECU50 determines in S66 whether Vc increased as a result of the process in S61. If Vc increases (YES in S66), the ECU50 executes processes S67 and S77. In S67, the ECU50 saves diagnostic D5 to its storage device. Diagnostic D5 indicates that relay C2 is welded in the "C2 connected" state. After that, the process in S77 described above is executed, and the process flow F1 (inspection control) ends.

[0065] If neither Va nor Vc increased as a result of the processing in S61 (NO in S66), the ECU 50 drives relay C2 to "C2 connected internally" in S71. Subsequently, in S72, the ECU 50 drives relay C1 to "C1 connected externally" and instructs the power conversion circuit 110 to supply AC power. The control of relay C1 and the control of power conversion circuit 110 may be performed simultaneously or sequentially. In the following S73, the ECU 50 determines whether Va increased as a result of the processing in S71 and S72. If Va increased (YES in S73), the ECU 50 executes the processes in S74 and S77. In S74, the ECU 50 saves diagnostic D2 to the memory. Diagnostic D2 is information indicating that relay C2 is welded in the "C2 connected externally" state. After that, the process in S77 described above is executed, and the processing flow F1 (inspection control) ends.

[0066] If Va does not increase as a result of processing S71 and S72 (NO in S73), ECU50 determines in S75 whether Vc increased as a result of processing S71 and S72. If Vc increases (YES in S75), ECU50 executes processes S76 and S77. In S76, ECU50 saves diagnostic D3 to the storage device. Diagnostic D3 is information indicating that relay C1 is welded in the "C1 connected" state. After that, the process in S77 described above is executed, and processing flow F1 (inspection control) ends.

[0067] If neither Va nor Vc increases as a result of processing S71 and S72 (NO in S75), the ECU 50 determines in S78 that the charger 100 is functioning correctly and executes "C1 connected". This returns the state of relays C1 and C2 to their state before the test.

[0068] In processing flow F1, S61, S64, and S66 correspond to an example of the "third inspection," and S71 to S73 and S75 correspond to an example of the "fourth inspection." As described above, the third inspection is started when vehicle 1 starts running. If the charger 100 is determined not to be faulty in the third inspection, the fourth inspection is performed. However, this is not limited to this, and after vehicle 1 starts running, the ECU 50 may start processing flow F1 at a timing when the voltage applied to the power line PL1 has stabilized (i.e., while vehicle 1 is running). For example, the ECU 50 may start processing flow F1 when a predetermined time has elapsed since the ECU 50 switched the SMR31 from the disconnected state to the connected state in order to start vehicle 1 running. The ECU 50 may also execute processing flow F1 each time a predetermined amount of time has elapsed while vehicle 1 is running.

[0069] Figure 3 is a diagram illustrating the state of the charger 100 when a normal judgment is made in processing flow F1. In the time chart, "t" represents timing. Line L21 shows the output voltage pattern of the power conversion circuit 110. Line L21 indicates whether the power conversion circuit 110 is in a stopped state (0V), an AC output state (power supply), or a DC output state (charging) at each timing. Lines L22, L23, and L24 show the transitions of Va, Vb, and Vc, respectively. Lines L25 and L26 show the transitions of the connection state (external connection / internal connection) of relays C1 and C2, respectively.

[0070] Referring to Figure 3, when vehicle 1 starts moving, the processing flow F1 shown in Figure 2 is executed. Due to the processing in S61, the "C2 external connection" control (see line L26) is executed at t21. Also, the power conversion circuit 110 is controlled to go from the stopped state to the AC output state at t21, and from the AC output state to the stopped state at t22 (see line L21). During the period t21 to t22, Vb changes according to the pattern shown by line L21 (see line L23). For this reason, the power conversion circuit 110 is judged to be normal. Also, during the period t21 to t22, when voltage is applied between wires PL13a and PL13b by the battery 30, the ECU 50 controls the switching device 120 so that wire PL13a is electrically connected to power line PL2 and wire PL13b is electrically connected to power line PL3 (see lines L23, L25, L26). In the example shown in Figure 3, during the period t21-t22, both Va and Vc remain unchanged and at 0V (see lines L22 and L24). Therefore, the third inspection determines that the charger 100 is not faulty.

[0071] Furthermore, the processing in S71 executes the "C2 internal connection" control at t23 (see line L26). The processing in S72 executes the "C1 external connection" control at t24 (see line L25). Also, the power conversion circuit 110 is controlled to switch from a stopped state to an AC output state at t24, and from an AC output state to a stopped state at t25 (see line L21). During the period t24-t25, when a voltage is applied between wires PL13a and PL13b by the battery 30, the ECU 50 controls the switching device 120 so that wire PL13a is electrically connected to power line PL3 and wire PL13b is electrically connected to power line PL2 (see lines L23, L25, L26). In the example shown in Figure 3, during the period t24-t25, neither Va nor Vc changes and remains at 0V (see lines L22, L24). Therefore, in the fourth inspection, it was determined that charger 100 was not faulty, and "C1 connection" was executed in t26.

[0072] Figure 4 is a diagram illustrating the state of the charger 100 when diagnostic D1 is recorded in processing flow F1. In the example shown in Figure 4, as indicated by line L23A, Vb does not rise during period t21-t22 due to a failure in the power conversion circuit 110. Therefore, NO is determined at S62 in Figure 2, and diagnostic D1 is recorded.

[0073] Figure 5 is a diagram illustrating the state of the charger 100 when diagnostic D4 is recorded in processing flow F1. In the example shown in Figure 5, relay C1 is welded in a state where it is connected to wire PL11b (C1 external connection state), as indicated by line L25A. As a result, Va increases during the period t21-t22 (see line L22A). This leads to a determination of YES at S64 in Figure 2, and diagnostic D4 is recorded.

[0074] Figure 6 is a diagram illustrating the state of the charger 100 when diagnostic D5 is recorded in processing flow F1. In the example shown in Figure 6, relay C2 is welded in a connected state with wire PL12a (connected in C2), as indicated by line L26A. As a result, Vc rises during the period t21-t22 (see line L24A). This leads to a YES determination at S66 in Figure 2, and diagnostic D5 is recorded.

[0075] Figure 7 is a diagram illustrating the state of the charger 100 when diagnostic D2 is recorded in processing flow F1. In the example shown in Figure 7, relay C2 is welded in a state where it is connected to wire PL11a (C2 externally connected), as indicated by line L26B. As a result, Va increases during the period t24-t25 (see line L22B). This leads to a determination of YES at S73 in Figure 2, and diagnostic D2 is recorded.

[0076] Figure 8 is a diagram illustrating the state of the charger 100 when diagnostic D3 is recorded in processing flow F1. In the example shown in Figure 8, relay C1 is welded in a connected state with wire PL12b (connected in C1), as indicated by line L25B. As a result, Vc rises during the period t24-t25 (see line L24B). This leads to a YES determination at S75 in Figure 2, and diagnostic D3 is recorded.

[0077] When the AC charging is finished, the ECU 50 further performs the inspection control shown in Figure 9. Figure 9 is a flowchart of the second inspection control according to this embodiment. In this embodiment, when the vehicle 1 changes from a driving state to a parked state, the ECU 50 controls the SMR 31 to a shut-off state, the power conversion circuit 110 to a stopped state, and the switching device 120 to a first switching state. When the AC connector is connected to the AC inlet 11 of the parked vehicle 1 and the AC connector is locked, the ECU 50 connects the SMR 31 and performs a pre-power supply inspection. If no abnormality is found in the pre-power supply inspection, the ECU 50 sets the power conversion circuit 110 to a DC output state and starts AC charging.

[0078] The ECU 50 determines whether the conditions for terminating AC charging have been met during AC charging. AC charging continues as long as the conditions for terminating AC charging have not been met. The conditions for terminating AC charging may be met when the State of Charge (SOC) of the battery 30 reaches a target value through AC charging. SOC indicates the remaining charge, and is expressed as a percentage from 0 to 100% of the current charge amount relative to the charge amount when fully charged. The conditions for terminating AC charging may also be met when a predetermined time has elapsed since the start of AC charging. Furthermore, the conditions for terminating AC charging may be met in response to a charging termination request from the user.

[0079] When the conditions for terminating AC charging are met, the ECU 50 stops the power conversion circuit 110 and starts the processing flow F2 shown in Figure 9. At the start of processing flow F2, if the charger 100 is functioning correctly, the switching device 120 is in the first switching state ("C1 externally connected" and "C2 externally connected"). Therefore, the voltage from the AC power supply equipment (power line PL2) is applied to the power conversion circuit 110.

[0080] In S11, the ECU 50 drives relay C2 to "C2 connected". Specifically, the ECU 50 sends a control command for this drive. In the following S12, the ECU 50 determines whether Vb has decreased as a result of the process in S11. If Vb has not decreased (NO in S12), the ECU 50 saves diagnostic D2 to the memory in S13, and then executes the processes in S31 to S33 described below.

[0081] In S31, the ECU 50 controls the HMI 80 to notify the user that an abnormality has been detected. The HMI 80 may also notify the user of the abnormality by illuminating a lamp. The HMI 80 may display a message indicating that the DC charging sequence will be stopped due to an abnormality in the charging system. The HMI 80 may also display a message prompting the user to replace the faulty charger 100. The HMI 80 may display the location of a place where the charger 100 can be replaced (e.g., the nearest dealer) on a map.

[0082] In the following step S32, the ECU 50 requests the AC power supply equipment to stop supplying power (stop charging). This stops the power supply from the AC power supply equipment to the AC inlet 11. Subsequently, in S33, the ECU 50 unlocks the AC connector. This allows the user to remove the AC connector from the AC inlet 11. Once the process in S33 is executed, the processing flow F2 ends.

[0083] If Vb decreases as a result of the processing in S11 (YES in S12), the ECU 50 drives relay C1 to "C1 connected in" in S21 and relay C2 to "C2 connected out" in S22. Specifically, the ECU 50 sends control commands to drive each of these relays. The driving of each relay may be performed simultaneously or sequentially (either relay may be driven first).

[0084] In the following S23, the ECU 50 determines whether Vb has increased as a result of the processes in S21 and S22. If Vb has increased (YES in S23), the ECU 50 saves diagnostic D4 to the memory in S24 and then executes the processes in S31 to S33 described above. On the other hand, if Vb has not increased (NO in S23), the ECU 50 determines in S31A that the charger 100 is functioning normally and executes "C2 connected". This puts the switching device 120 into the second switching state. Subsequently, the ECU 50 executes the processes in S32 and S33 described above. In either case, once the process in S33 is executed, the processing flow F2 ends.

[0085] In processing flow F2, S11 and S12 correspond to an example of the "first inspection," and S21 to S23 correspond to an example of the "second inspection." As described above, the first inspection is started when AC charging is completed. If the charger 100 is determined not to be faulty in the first inspection, the second inspection is performed. After the completion of processing flow F2, the ECU 50 may switch the SMR31 from the connected state to the disconnected state. Also, if in processing flow F2 it is determined that one of relays C1 and C2 is welded in an external connection state, the ECU 50 may control the other relay to an internal connection state after the completion of processing flow F2.

[0086] Figure 10 is a diagram illustrating the state of the charger 100 when a normal determination is made in processing flow F2. In Figure 10, line L11 indicates the charge request signal (permit / stop) transmitted from vehicle 1 (ECU 50) to the AC power supply equipment. When the charge request signal indicates "permit," the AC power supply equipment supplies power to vehicle 1. When the charge request signal indicates "stop," the AC power supply equipment does not supply power to vehicle 1. Lines L12 to L16 in Figure 10 correspond to lines L22 to L26 in Figure 3, respectively. However, lines L12 and L13 each indicate charging power (power to battery 30), not power supply power (power to the outside of the vehicle).

[0087] Referring to Figure 10, the processing flow F2 shown in Figure 9 is executed when AC charging is complete. At the start of processing flow F2, a voltage is applied between wires PL2a and PL2b that constitute the power line PL2. In this state, the processing in S11 executes the "C2 connection" control (see line L16) at t11. In this way, when a voltage is applied between wires PL2a and PL2b, the ECU 50 controls the switching device 120 so that wires PL2b and PL11b are electrically connected to wire PL13b (and thus to the battery 30) by relay C1, and wires PL2a and PL11a are disconnected from wire PL13a (and thus to the battery 30) by relay C2 (see lines L12, L15, L16). In the example shown in Figure 10, the voltage (Vb) applied to the battery 30 side of the switching device 120 is reduced by the processing in S11 (see line L13). Therefore, the first inspection determines that charger 100 is not malfunctioning.

[0088] Furthermore, the process in S21 executes the "C1 internal connection" control at t12 (see line L15). The process in S22 executes the "C2 external connection" control at t13 (see line L16). In this way, if the ECU 50 determines in the first inspection that the charger 100 is not faulty, relay C2 electrically connects wires PL2a and PL11a to wire PL13a (and consequently to the battery 30), and relay C1 disconnects wires PL2b and PL11b from wire PL13b (and consequently to the battery 30) (see lines L15, L16). In the example shown in Figure 10, even after the processes in S21 and S22 are executed, the voltage (Vb) applied to the battery 30 side of the switching device 120 does not rise (see line L13). For this reason, the charger 100 is determined not to be faulty in the second inspection as well. Subsequently, at t14, "C2 connection" is performed (see line L16), and at t15, a request is made to stop the power supply to the AC power supply equipment (see line L11). As a result, at t16, the power supply from the AC power supply equipment to vehicle 1 is stopped (see line L12), and at t17, the connector is unlocked.

[0089] Figure 11 is a diagram illustrating the state of the charger 100 when diagnostic D2 is recorded in processing flow F2. In the example shown in Figure 11, relay C2 is welded in a state where it is connected to wire PL11a (C2 externally connected), as indicated by line L16A. Therefore, the voltage (Vb) applied to the battery 30 side of the switching device 120 does not decrease due to the processing in S11 (see line L13A). In this case, AC charging is terminated by processing different from the normal state (processing for abnormal conditions). Specifically, processing in S21 is not executed (see line L15A), and at t15a, a request is made to stop the power supply to the AC power supply equipment (see line L11A). As a result, at t16a, the power supply from the AC power supply equipment to the vehicle 1 is stopped (see lines L12A, L13A), and at t17a, the connector is unlocked.

[0090] Figure 12 is a diagram illustrating the state of the charger 100 when diagnostic D4 is recorded in processing flow F2. In the example shown in Figure 12, relay C1 is welded in a state where it is connected to wire PL11b (C1 external connection state), as indicated by line L15B. Therefore, when "C2 external connection" is executed at t13 (see line L16B), the voltage (Vb) applied to the battery 30 side from the switching device 120 increases (see line L13B). In this case, AC charging is terminated by a different process than in the normal case (processing in the abnormal case). Specifically, at t15b, a request is made to stop the power supply to the AC power supply equipment (see line L11B). As a result, at t16b, the power supply from the AC power supply equipment to the vehicle 1 is stopped (see lines L12B, L13B), and at t17b, the connector is unlocked.

[0091] Figure 13 is a flowchart showing the control prohibition process by the ECU 50. The processing flow F3 shown in Figure 13 is executed by the ECU 50 each time it is started up. Processing flow F3 is also executed when at least one of the diagnostics D1 to D5 is recorded in the ECU 50 by the processing flow F1 or F2 described above. Initially, none of the diagnostics D1 to D5 are recorded in the ECU 50. Furthermore, even if at least one of the diagnostics D1 to D5 is recorded in the storage device of the ECU 50, the diagnostics D1 to D5 in the storage device are erased when the charger 100 is replaced.

[0092] Referring to Figure 13, the ECU 50 determines in S41, S42, S43, S44, and S45 whether diagnostics D1, D2, D3, D4, and D5 exist in the storage device, respectively.

[0093] If diagnostic D1 is present (YES in S41), control of AC charging and external power supply by the ECU 50 is prohibited in S51. For example, if the user requests AC charging or external power supply from the ECU 50 via the HMI 80, the ECU 50 will reject the request. In this case, the HMI 80 may notify the user to replace the charger 100.

[0094] If diagnostic D1 does not exist (NO in S41), and diagnostic D2 or D4 exists (YES in S42 or S44), then in S52 or S54, control by the ECU 50 regarding external power supply is prohibited. For example, if the user requests external power supply from the ECU 50 via the HMI 80, the ECU 50 will reject the request. In this case, the HMI 80 may notify the user to replace the charger 100.

[0095] If diagnostic D1 does not exist (NO in S41), and diagnostic D3 or D5 exists (YES in S43 or S45), then control by the ECU 50 regarding AC charging is prohibited in S53 or S55. For example, if the user requests AC charging from the ECU 50 via the HMI 80, the ECU 50 will reject the request. In this case, the HMI 80 may also notify the user to replace the charger 100.

[0096] In this embodiment, the AC charging initiation condition includes the fact that none of the diagnostic codes D1, D3, and D5 are stored in the ECU 50. Furthermore, the external power supply initiation condition includes the fact that none of the diagnostic codes D1, D2, and D4 are stored in the ECU 50. Therefore, if any of the diagnostic codes D1, D3, or D5 are stored in the ECU 50, it is determined in one of S51, S53, or S55 that the AC charging initiation condition is not met, and AC charging is prohibited. Similarly, if any of the diagnostic codes D1, D2, or D4 are stored in the ECU 50, it is determined in one of S51, S52, or S54 that the external power supply initiation condition is not met, and external power supply is prohibited. Note that when the charger 100 is replaced, the diagnostic codes D1 to D5 are erased, and the processes in S51 to S55 are not executed. Therefore, the respective initiation conditions for AC charging and external power supply can be met. For example, AC charging will begin when other requirements for starting AC charging (e.g., AC connector locking is complete, and the cable check is deemed successful) are met. However, not limited to the above, both AC charging and external power supply may be prohibited if any of diagnostic codes D2 to D5 are stored in the ECU50.

[0097] As described above, the ECU 50 (control device) according to this embodiment is configured to control the charger 100, which is electrically connected to the power line PL2 (first power line), the power line PL3 (second power line), and the battery 30, respectively. During AC charging, the ECU 50 controls the charger 100 so that the battery 30 and the power line PL2 are electrically connected via the charger 100, and the charger 100 charges the battery 30 using the power supplied from the power line PL2. During external power supply, the ECU 50 controls the charger 100 so that the battery 30 and the power line PL3 are electrically connected via the charger 100, and the charger 100 supplies power to the power line PL3 using the power supplied from the battery 30. The ECU 50 executes processing flows F1 to F3 (Figures 2, 9, and 13). In this embodiment, each process is executed by one or more processors executing programs stored in one or more memories. However, these processes may be executed by hardware (electronic circuits) alone without using software.

[0098] Specifically, the ECU 50 controls the switching device 120 through processing S11 and S12 in processing flow F2 (Figure 9) so that when a voltage is applied between wires PL2a and PL2b constituting the power line PL2, wire PL2b (first wire) is electrically connected to the battery 30 and wire PL2a (second wire) is disconnected from the battery 30, and determines whether the switching device 120 is faulty based on the voltage (Vb) applied to the battery 30 side of the switching device 120. If it is determined in S12 that the switching device 120 is not faulty, the ECU 50 controls the switching device 120 through processing S21 to S23 in processing flow F2 (Figure 9) so that wire PL2a (second wire) is electrically connected to the battery 30 and wire PL2b (first wire) is disconnected from the battery 30, and determines whether the switching device 120 is faulty based on the voltage (Vb) applied to the battery 30 side of the switching device 120. This configuration makes it possible to accurately determine the status of the charging system (especially whether or not the switching device 120 is malfunctioning).

[0099] In the processing flow F2 shown in Figure 9, when voltage is applied from power line PL2 to power conversion circuit 110, the ECU 50 controls the switching device 120 so that relay C1 connects power line PL2 to power conversion circuit 110 and relay C2 connects power line PL3 to power conversion circuit 110 (S11). The ECU 50 then determines that relay C2 is welded if Vb does not decrease as a result of this control (S12, S13). This inspection makes it easier for the ECU 50 to accurately understand the state of relay C2.

[0100] Furthermore, if the switching device 120 is determined not to be faulty in S12 of Figure 9, the ECU 50 controls the switching device 120 so that relay C1 connects the power conversion circuit 110 to power line PL3 and relay C2 connects the power conversion circuit 110 to power line PL2 (S21, S22). Then, if Vb rises as a result of this control, the ECU 50 determines that relay C1 is welded (S23, S24). This type of inspection makes it easier for the ECU 50 to accurately understand the state of relay C1.

[0101] Furthermore, the ECU 50 initiates the processing flow F1 shown in Figure 2 when the vehicle 1 starts driving and / or while driving. In processing flow F1, the ECU 50 controls the charger 100 so that relay C1 connects the power conversion circuit 110 to power line PL3, relay C2 connects the power conversion circuit 110 to power line PL2, and the power conversion circuit 110 converts the DC power supplied from the battery 30 into AC power and outputs it to the switching device 120 (S61). In this control, the ECU 50 determines that relay C1 is welded if Va rises (S64, S65), and determines that relay C2 is welded if Vc rises (S66, S67). Furthermore, if it is determined that neither relay C1 nor C2 is welded, the ECU 50 controls the charger 100 so that relay C1 connects to power line PL2 and relay C2 connects to power line PL3 and power conversion circuit 110 converts the DC power supplied from battery 30 to AC power and outputs it to switching device 120 (S71, S72). In this control, the ECU 50 determines that relay C2 is welded if Va rises (S73, S74), and that relay C1 is welded if Vc rises (S75, S76). This inspection makes it easier for the ECU 50 to accurately grasp the status of relays C1 and C2.

[0102] In this embodiment, if relay C2 is determined to be welded in S66 and S67 (third inspection) in Figure 2, or if relay C1 is determined to be welded in S75 and S76 (fourth inspection) in Figure 2, the first control (e.g., AC charging control) for supplying power from power line PL2 to battery 30 is prohibited in S55 or S53 of Figure 13, respectively. Also, if relay C2 is determined to be welded in S12 and S13 (first inspection) in Figure 9, or if relay C1 is determined to be welded in S23 and S24 (second inspection) in Figure 9, the second control (e.g., external power supply control) for supplying power from battery 30 to power line PL3 is prohibited in S52 or S54 of Figure 13, respectively. Furthermore, if relay C1 is determined to be welded in S64 and S65 (third inspection) in Figure 2, or if relay C2 is determined to be welded in S73 and S74 (fourth inspection) in Figure 2, then the second control (e.g., external power supply control) for supplying power from battery 30 to power line PL3 is prohibited in S54 or S52 of Figure 13, respectively. This control prohibition process makes it possible to prevent control malfunctions.

[0103] In the vehicle 1 according to the above embodiment, the AC inlet 11 is used only for charging. However, it is not limited to this, and the AC inlet 11 may also be used for external power supply (power supply from a power storage device mounted on the vehicle 1 to the outside of the vehicle). The vehicle 1 may be configured to output the power stored in the battery 30 to the outside of the vehicle through one of the AC inlet 11 and the outlet 12 selected by the switching device 120. In this configuration, if at least one of relays C1 and C2 is welded in an internal connection state, the switching device 120 will not be able to select the AC inlet 11 (power path PL2). Also, if at least one of relays C1 and C2 is welded in an external connection state, the switching device 120 will not be able to select the outlet 12 (power path PL3). Therefore, the ECU 50 may prohibit external power supply using the AC inlet 11 if at least one of relays C1 and C2 is welded in an internal connection state. Furthermore, the ECU 50 may prohibit external power supply using the outlet 12 if at least one of relays C1 and C2 is welded in an externally connected state.

[0104] The vehicle configuration is not limited to the configuration shown in Figure 1. For example, the configuration of the switching device may be changed. The switching device may include three or more C-contact relays, or it may include an A-contact relay and / or a B-contact relay. Also, the circuit configuration shown in Figure 1 may be changed.

[0105] Figure 14 shows a modified configuration of the vehicle shown in Figure 1. Referring to Figure 14, in the modified vehicle 1A, an AC / DC inlet 11A is provided instead of the AC inlet 11 and DC inlet 21. The AC / DC inlet 11A is an inlet common to both AC charging and DC charging. Both AC connectors and DC connectors can be connected to the AC / DC inlet 11A. The AC / DC inlet 11A is electrically connected to port 102 of the charger 100 and to power line PL1, respectively. Specifically, power line PL2 connected to port 102 is connected to the middle of power line PL4 (more specifically, to the part of power line PL4 closer to the AC / DC inlet 11A than relay 22). During AC charging, the ECU 50 controls the charger 100 by keeping relay 22 in the off state. During DC charging, the ECU 50 selects power line PL3 using the switching device 120 and keeps relay 22 in the connected state. If at least one of relays C1 and C2 is welded in an externally connected state, the switching device 120 will be unable to select power path PL3. Therefore, the ECU 50 may prohibit DC charging if at least one of relays C1 and C2 is welded in an externally connected state.

[0106] The control device is not limited to energy storage systems mounted on vehicles, but is applicable to any vehicle. The control device may also be applied to vehicles other than automobiles (railway vehicles, ships, airplanes, amphibious vehicles, etc.), mobile machinery (agricultural machinery, construction machinery, etc.), unmanned mobile vehicles (automated guided vehicles (AGVs), walking robots, security robots, flying drones, underwater drones, robotic cleaners, space probes, etc.), wearable robots (e.g., caregiving robots), stationary robots (e.g., industrial robots), or energy storage systems used in buildings (houses, factories, etc.).

[0107] The processing flows F1, F2, and F3 shown in Figures 2, 9, and 13 can be modified as appropriate. For example, the order of processing may be changed or unnecessary steps may be omitted depending on the purpose. Also, the content of any of the processes may be changed. For example, the inspection of the power conversion circuit 110 (S62 and S63 in Figure 2) may be omitted.

[0108] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of the present invention is indicated by the claims rather than by the description of the embodiments above, and all modifications within the meaning and scope equivalent to the claims are intended to be included. [Explanation of Symbols]

[0109] 1 Vehicle, 30 Battery, 50 ECU, 100 Charger, 110 Power Conversion Circuit, 120 Switching Device, C1, C2 Relays, PL1, PL2, PL3, PL4, PL5 Power Lines, PL11a, PL11b, PL12a, PL12b, PL13a, PL13b Wires, Sa, Sb, Sc Voltage Sensors.

Claims

1. A control device for controlling a charger configured to be electrically connectable to a first power line, a second power line, and an energy storage device, The charger includes a switching device configured to electrically connect either the first power line or the second power line to the energy storage device. The control device is configured to control the charger such that the energy storage device and the first power line are electrically connected via the charger, and the charger charges the energy storage device using power supplied from the first power line. The control device is configured to control the charger such that the energy storage device and the second power line are electrically connected via the charger, and the charger supplies power to the second power line using the power supplied from the energy storage device. The control device is A first inspection is performed in which, when a voltage is applied between the first and second wires constituting the first power circuit, the switching device is controlled so that the first wire is electrically connected to the energy storage device and the second wire is disconnected from the energy storage device, and the presence or absence of a malfunction in the switching device is determined based on the voltage applied to the energy storage device side of the switching device, If the first inspection determines that the charger is not faulty, the second inspection involves controlling the switching device so that the second wire is electrically connected to the energy storage device and the first wire is disconnected from the energy storage device, and determining whether the switching device is faulty based on the voltage applied to the energy storage device side of the switching device, A control device configured to perform the following actions.

2. A charging system comprising the control device described in claim 1 and the charger controlled by the control device, The aforementioned charger, A power conversion circuit located between the switching device and the energy storage device, A first voltage sensor for detecting a first voltage applied between the switching device and the power conversion circuit, Furthermore, The power conversion circuit is configured to convert the DC power supplied from the energy storage device into AC power and output it to the switching device, and to convert the AC power supplied from the first power line into DC power and output it to the energy storage device. A charging system in which the first voltage sensor is configured to output the detected value of the first voltage to the control device.

3. The switching device includes a first C-contact relay and a second C-contact relay, The charging system according to claim 2, wherein each of the first C-contact relay and the second C-contact relay is configured to disconnect the power conversion circuit from the other power path when the power conversion circuit is connected to one of the first power path and the second power path.

4. The charging system according to claim 3, wherein the control device is configured to determine that the second C contact relay is welded when, in the first inspection, the first voltage does not decrease by controlling the switching device so that the first C contact relay connects the power conversion circuit to the first power circuit and the second C contact relay connects the power conversion circuit to the second power circuit when a voltage is applied from the first power circuit to the power conversion circuit.

5. The charging system according to claim 4, wherein the control device is configured to determine that the first C contact relay is welded when the first voltage rises in the second inspection by controlling the switching device so that the first C contact relay connects the power conversion circuit to the second power path and the second C contact relay connects the power conversion circuit to the first power path.

6. A vehicle comprising a charging system according to any one of claims 2 to 5, The aforementioned vehicle is An inlet electrically connected to the first power circuit, The outlet electrically connected to the second power circuit, Furthermore, The vehicle is configured to perform AC charging, which involves converting AC power supplied from outside the vehicle to the inlet into DC power using the charger, and supplying the converted DC power to the energy storage device. The control device is configured to start the first inspection when the AC charging is terminated, in a vehicle.

7. A vehicle comprising the charging system described in claim 5, The vehicle is configured to be able to run using the power output from the energy storage device, The aforementioned charger, A second voltage sensor for detecting the second voltage applied to the first power line, A third voltage sensor for detecting the third voltage applied to the second power path, Furthermore, The second voltage sensor and the third voltage sensor are configured to output the detected values ​​of the second voltage and the third voltage, respectively, to the control device. The control device is configured to perform a third inspection in which, when the first C-contact relay connects the power conversion circuit to the second power path, and the second C-contact relay connects the power conversion circuit to the first power path, and the power conversion circuit converts the DC power supplied from the energy storage device into AC power and outputs it to the switching device, the first C-contact relay is determined to be welded if the second voltage rises, and the second C-contact relay is determined to be welded if the third voltage rises. The control device is configured to perform a fourth inspection if the third inspection determines that neither the first C contact relay nor the second C contact relay is welded. The control device is configured such that, in the fourth inspection, when the first C-contact relay connects the power conversion circuit to the first power path, the second C-contact relay connects the power conversion circuit to the second power path, and the power conversion circuit converts the DC power supplied from the energy storage device into AC power and outputs it to the switching device, the control device determines that the second C-contact relay is welded if the second voltage rises, and determines that the first C-contact relay is welded if the third voltage rises. The control device is configured to initiate the third inspection when the vehicle starts moving and / or while it is moving.

8. The control device is configured to prohibit the first control for supplying power from the first power line to the energy storage device in each case where the third inspection determines that the second C contact relay is welded, and in the fourth inspection determines that the first C contact relay is welded. The vehicle according to claim 7, wherein the control device is configured to prohibit the second control for supplying power from the energy storage device to the second power line in each of the following cases: when the second C contact relay is determined to be welded in the first inspection; when the first C contact relay is determined to be welded in the second inspection; when the first C contact relay is determined to be welded in the third inspection; and when the second C contact relay is determined to be welded in the fourth inspection.

Citation Information

Patent Citations

  • On-vehicle charging apparatus

    JP2021112017A