JP7669822B2 - Charging System - Google Patents

Description

This disclosure relates to a charging system.

JP 2012-170181 A (Patent Document 1) discloses a technology for detecting a connection abnormality of a charging plug (for example, a charging plug that has been left inserted or fallen off) before charging an electric storage device mounted on a vehicle.

JP 2012-170181 A

The technology described in Patent Document 1 can detect connection abnormalities in the charging plug, but cannot detect other abnormalities (errors).

The present disclosure has been made to solve the above problems, and its purpose is to provide a charging system that can detect and record various errors that may occur during charging before charging.

The charging system according to the present disclosure includes a control device that starts charging the power storage device through a plurality of steps before charging the power storage device. Each of the plurality of steps is a step in which the control device executes a process involving communication with another control device. The control device is configured to determine the presence or absence of an error in each of the plurality of steps. When it is determined that an error has occurred, the control device is configured to record error information indicating in which of the plurality of steps it has been determined that the error has occurred.

Hereinafter, determining whether an error exists or not will be referred to simply as "error determination." In addition, the above control device will be referred to as the "target control device" to distinguish it from the other control devices.

The target control device performs an error determination for each step. At this time, the target control device can check for the presence or absence of errors not only in the control range of the target control device but also in the control range of the other control devices by communicating with the other control devices. This allows the target control device to check for the presence or absence of various errors (including communication errors) that may occur during charging before charging begins. Then, if it is determined that an error has occurred in any step, the target control device records error information indicating at which step the error occurred. By recording such error information, for example, a user or maintenance company (including a repair company) can easily determine at which step the error occurred, making it easier to identify the cause of the error.

The power storage device may be a power storage device mounted on a vehicle. The vehicle may be configured to run by converting the electric power stored in the power storage device into power. The vehicle may be an EV (electric vehicle) or a PHV (plug-in hybrid vehicle).

The charging system may include a plurality of control devices as other control devices. Charging of the power storage device may be external charging in which the power storage device mounted on the vehicle is charged using power supplied from a power source external to the vehicle.

The above steps may include a first step in which the target control device turns on the power of the other control devices involved in the charging control, a second step in which the target control device requests information indicating the state of the power storage device from the other control devices, a third step in which the target control device requests permission to charge from the other control devices, and a fourth step in which the target control device transmits a charging command to the other control devices. The target control device may perform an error determination before processing each step.

In the error determination before the processing of the first step, it may be determined that an error has occurred if the charging plug is not properly connected to the vehicle inlet. Also, in the error determination before the processing of the first step, it may be determined that an error has occurred if power is not normally supplied to the vehicle from a power source external to the vehicle.

In the error determination before the second step, it may be determined that an error has occurred if the vehicle is not in a parked state.

In the error determination before the processing of the third step, it may be determined that an error has occurred if an abnormality that prevents charging from starting has occurred in the vehicle. In the error determination before the processing of the third step, it may be determined that an error has occurred if the state of the power storage device is abnormal.

In the error determination before the processing of the fourth step, it may be determined that an error has occurred if charging permission is not granted in response to the processing of the third step (request for charging permission).

This disclosure makes it possible to provide a charging system that can detect and record various errors that may occur during charging before charging.

1 is a diagram showing an overview of a vehicle equipped with a charging system according to an embodiment of the present disclosure. 2 is a diagram for explaining external charging of the power storage device performed in the vehicle shown in FIG. 1 . FIG. 10 is a diagram for explaining an error determination executed by a target control device when external charging of a power storage device is started in a charging system according to an embodiment of the present disclosure. FIG. 4 is a diagram showing a flow of processes executed by each control device when external charging of a power storage device is started in a charging system according to an embodiment of the present disclosure. FIG.

Embodiments of the present disclosure will be described in detail with reference to the drawings. In the drawings, identical or corresponding parts are given the same reference numerals and their description will not be repeated. Hereinafter, the electronic control unit will be referred to as "ECU."

Figure 1 is a diagram showing an overview of a vehicle equipped with a charging system according to this embodiment. Referring to Figure 1, vehicle 100 is a PHV (plug-in hybrid vehicle). In this embodiment, a front-wheel drive, four-wheel vehicle is assumed, but the number of wheels and the drive system can be changed as appropriate. For example, the drive system may be four-wheel drive.

The vehicle 100 includes a charging system 1, a first motor generator 21a (hereinafter referred to as "MG21a"), a second motor generator 21b (hereinafter referred to as "MG21b"), a motor ECU 23, a PCU (Power Control Unit) 24, an engine 31, an engine ECU 33, a transmission mechanism 421, and a hydraulic circuit 422.

The charging system 1 includes a main battery 11, a voltage sensor 12a, a current sensor 12b, a temperature sensor 12c, an SMR (System Main Relay) 14, an HV (Hybrid Vehicle)-ECU 50, an inlet 81, a power conversion circuit 82, a charging relay 83, a BAT (Battery)-ECU 501, a PWC (Plugin Wireless Charge)-ECU 502, and a CHG (Charge)-ECU 503.

Each of the motor ECU 23, engine ECU 33, HV-ECU 50, BAT-ECU 501, PWC-ECU 502, and CHG-ECU 503 provided in the vehicle 100 is a microcomputer including a processor, a RAM (Random Access Memory), a storage device, and a communication I/F (interface). The processor may be, for example, a CPU (Central Processing Unit). The communication I/F may include, for example, a CAN (Controller Area Network) controller. The RAM functions as a working memory that temporarily stores data processed by the processor. The storage device is configured to be able to save stored information. The storage device may include, for example, a ROM (Read Only Memory) and a rewritable non-volatile memory. In addition to programs, the storage device stores information used by the programs (for example, maps, formulas, and various parameters). The processor executes the programs stored in the storage device, thereby performing various controls in the ECU. However, this is not limited to this, and the various controls may be performed by dedicated hardware (electronic circuits). The number of processors each ECU has may be any number, and any ECU may have multiple processors.

Each ECU is connected to a specific ECU so as to be able to communicate with it. The communication method is, for example, CAN communication. The HV-ECU 50 is connected to each of the motor ECU 23, the engine ECU 33, the BAT-ECU 501, and the PWC-ECU 502 so as to be able to communicate with them. The PWC-ECU 502 is connected to each of the HV-ECU 50, the BAT-ECU 501, and the CHG-ECU 503 so as to be able to communicate with them. The PWC-ECU 502 may mediate communication between the HV-ECU 50 and the CHG-ECU 503.

The main battery 11 is a rechargeable power storage device. The main battery 11 is configured to supply power to the PCU 24 (and thus to the MGs 21a and 21b, which are the traction motors). The main battery 11 may include one or more power storage devices selected from the group consisting of a liquid secondary battery, an all-solid-state secondary battery, a battery pack, and an electric double layer capacitor. Examples of secondary batteries include a lithium-ion battery or a nickel-metal hydride battery. The main battery 11 in this embodiment corresponds to an example of a "power storage device" in accordance with the present disclosure.

The voltage sensor 12a detects the voltage of the main battery 11. The current sensor 12b detects the current flowing through the main battery 11. The temperature sensor 12c detects the temperature of the main battery 11. Each sensor outputs its detection result to the BAT-ECU 501. The BAT-ECU 501 can obtain the state of the main battery 11 (for example, temperature, current, voltage, SOC (State Of Charge), and internal resistance) using the detection results of each sensor.

The SMR 14 is configured to switch between connection and disconnection of an electrical path connecting the PCU 24 and the main battery 11. The main battery 11 is connected to the PCU 24 via the SMR 14. The SMR 14 is controlled by the HV-ECU 50. The SMR 14 is in a closed state (connected state), for example, when the vehicle 100 is running.

MG21a and 21b are each a motor generator. MG21a and MG21b have rotor shafts 43a and 43b, respectively. Rotor shafts 43a and 43b correspond to the rotation shafts of MG21a and MG21b, respectively. MG21a and 21b are provided with motor sensors 22a and 22b that detect the state (e.g., current, voltage, temperature, and rotation speed) of MG21a and 21b, respectively. Each of motor sensors 22a and 22b outputs the detection results to motor ECU 23.

Each of MGs 21a and 21b is electrically connected to the main battery 11 via the PCU 24 and the SMR 14. The PCU 24 is configured to include, for example, two inverters provided corresponding to MGs 21a and 21b, and a converter (neither shown) arranged between each inverter and the main battery 11. The PCU 24 is configured to supply the power stored in the main battery 11 to each of MGs 21a and 21b, and to supply the power generated by each of MGs 21a and 21b to the main battery 11.

The engine 31 is an internal combustion engine including multiple cylinders (e.g., four cylinders). The engine 31 generates power, for example, by burning fuel in each cylinder, and the generated power rotates a crankshaft (not shown) common to all cylinders. The rotation of the crankshaft also rotates the output shaft 41. The engine 31 is provided with an engine sensor 32 that detects the state of the engine 31 (e.g., intake volume, intake pressure, intake temperature, exhaust pressure, exhaust temperature, catalyst temperature, engine coolant temperature, and rotation speed). The engine sensor 32 outputs the detection results to the engine ECU 33.

The vehicle 100 further includes a single-pinion type planetary gear 431. The output shaft 41 of the engine 31 is connected to the planetary gear 431 via the transmission mechanism 421. The output shaft 42 of the transmission mechanism 421 and the rotor shaft 43a of the MG 21a are each connected to the planetary gear 431. The planetary gear 431 has a sun gear, a ring gear arranged coaxially with the sun gear, a pinion gear meshing with the sun gear and the ring gear, and a carrier that holds the pinion gear so that it can rotate and revolve. The output shaft 42 of the transmission mechanism 421 is connected to the carrier of the planetary gear 431. The rotor shaft 43a of the MG 21a is connected to the sun gear of the planetary gear 431. Torque is input to the carrier of the planetary gear 431 from the output shaft 42 of the transmission mechanism 421.

The transmission mechanism 421 is configured to be driven by a hydraulic circuit 422 to change the gear ratio. The hydraulic circuit 422 is configured to adjust the hydraulic pressure supplied to the transmission mechanism 421 according to commands from the HV-ECU 50. The HV-ECU 50 controls the hydraulic circuit 422 according to the shift range, for example, to put the transmission mechanism 421 into neutral or adjust the gear ratio. When the transmission mechanism 421 is in a non-neutral state, the planetary gear 431 is configured to divide and transmit the torque output by the engine 31 to the sun gear (and thus MG21a) and the ring gear. When the torque output by the engine 31 is output to the ring gear, a reaction torque from MG21a acts on the sun gear.

The planetary gear 431 and MG21b are configured so that the power output from the planetary gear 431 (i.e., the power output to the ring gear) and the power output from MG21b (i.e., the power output to the rotor shaft 43b) are combined and transmitted to the drive wheels 45a, 45b. More specifically, an output gear (not shown) that meshes with the driven gear 432 is attached to the ring gear of the planetary gear 431. In addition, a drive gear (not shown) attached to the rotor shaft 43b of MG21b also meshes with the driven gear 432. The driven gear 432 acts to combine the torque output from MG21b to the rotor shaft 43b and the torque output from the ring gear of the planetary gear 431. The combined driving torque is transmitted to the differential gear 44 and then to the driving wheels 45a, 45b via the drive shafts 44a, 44b that extend to the left and right from the differential gear 44.

The HV-ECU 50 receives detection values of the motor sensors 22a, 22b and the engine sensor 32 from the motor ECU 23 and the engine ECU 33 as necessary. The HV-ECU 50 also receives information indicating the state of the main battery 11 from the BAT-ECU 501 as necessary. Although not shown in the figure, other sensors (for example, a vehicle speed sensor, a fuel gauge, an odometer, an accelerator opening sensor, an atmospheric pressure sensor, and an outside air temperature sensor) are also mounted on the vehicle 100. The HV-ECU 50 can grasp information about the vehicle 100 based on the output of various sensors (on-board sensors) mounted on the vehicle 100.

The HV-ECU 50 is configured to output commands (control commands) for controlling the engine 31 to the engine ECU 33. The engine ECU 33 is configured to perform engine control according to commands from the HV-ECU 50. Specifically, the engine ECU 33 controls various actuators of the engine 31 (for example, a throttle valve, an ignition device, and an injector, not shown). The HV-ECU 50 can perform engine control through the engine ECU 33.

The HV-ECU 50 is configured to output commands (control commands) for controlling each of MG 21a and MG 21b to the motor ECU 23. The motor ECU 23 is configured to perform motor control in accordance with commands from the HV-ECU 50. Specifically, the motor ECU 23 generates current signals (for example, signals indicating the magnitude and frequency of the current) corresponding to the target torque of each of MG 21a and MG 21b in accordance with commands from the HV-ECU 50, and outputs the generated current signals to the PCU 24. The HV-ECU 50 can perform motor control through the motor ECU 23.

The vehicle 100 further includes a shift lever 101, a P position switch 102, and a power switch 103. The power switch 103 is a start-up switch for starting up the vehicle system. Start-up switches are generally called "power switches" or "ignition switches." By operating the power switch 103, the user can switch between an operating state (Ready-ON state) and a stopped state (Ready-OFF state) of the vehicle system.

The user can select one of N (neutral), R (reverse), D (drive), and B (brake) ranges by moving the shift lever 101 to a predetermined position (see FIG. 1). The user can select P (parking) range by stopping the vehicle 100 and pressing the P position switch 102. The HV-ECU 50 switches the shift range of the vehicle 100 to the range selected by the user. When the shift range is P range, the ring gear of the planetary gear 431 is locked by a parking device (not shown) that mechanically prevents the rotation of the ring gear of the planetary gear 431. This puts the vehicle 100 into a parked state. When the vehicle 100 is parked, the user can activate a parking brake (not shown) (a device that applies the brakes to prevent the vehicle 100 from moving when parked), thereby reducing the burden on the parking device.

The inlet 81 corresponds to the power receiving unit of the vehicle 100. The power conversion circuit 82 converts AC power supplied to the inlet 81 from outside the vehicle into DC power and outputs it. The DC power output from the power conversion circuit 82 is supplied to the main battery 11 via the charging relay 83 and the SMR 14. The power conversion circuit 82 functions as an on-board charger. The power conversion circuit 82 is controlled by the CHG-ECU 503. The charging relay 83 is controlled by the HV-ECU 50. With this configuration, the vehicle 100 can perform external charging of the main battery 11. Figure 2 is a diagram for explaining external charging of the main battery 11 performed in the vehicle 100.

Referring to FIG. 2 together with FIG. 1, the inlet 81 of the vehicle 100 is provided with a lid 81c. When the user opens the lid 81c, the inlet 81 is exposed as shown in the upper part of FIG. 2. Note that the position of the inlet 81 is not limited to the position shown in FIG. 2 (the rear side of the vehicle body) and can be set arbitrarily.

The inlet 81 is configured to be able to connect to a connector 430 of a charging cable 420 that is connected to an EVSE (Electric Vehicle Supply Equipment) 400. The connector 430 is located at the tip of the charging cable 420. The EVSE 400 has a built-in power supply circuit 410. The power supply circuit 410 performs a predetermined power conversion on the power supplied from an external power supply PG, and outputs the converted power to the charging cable 420. The external power supply PG may be a commercial power source (for example, a power system provided by a power company) that supplies AC power to the power supply circuit 410. In this embodiment, AC power is supplied from the external power supply PG to the connector 430 via the power supply circuit 410.

The inlet 81 is further provided with a lock mechanism including a lock pin 81a, a connection sensor 81b, and an actuator (not shown) that drives the lock mechanism. The connection sensor 81b detects whether the connector 430 is connected to the inlet 81 and outputs the detection result to the PWC-ECU 502 (Figure 1). The PWC-ECU 502 also controls the actuator. When the connector 430 is connected to the inlet 81, the PWC-ECU 502 controls the actuator to switch between a connector locked state and a connector unlocked state. The connector locked state is a state in which removal of the connector 430 from the inlet 81 is restricted. For example, when the connector 430 is connected to the inlet 81, the PWC-ECU 502 puts the inlet 81 into a connector locked state. In the connector locked state, the lock pin 81a driven by the actuator engages with the connector 430, thereby restricting removal of the connector 430. On the other hand, the connector unlocked state is a state in which removal of the connector 430 from the inlet 81 is permitted. For example, when external charging ends, the PWC-ECU 502 places the inlet 81 in a connector unlocked state. In the connector unlocked state, the lock pin 81a is no longer engaged with the connector 430, and removal of the connector 430 is permitted.

External charging of the main battery 11 is performed when the vehicle 100 is parked. When the vehicle 100 performs external charging of the main battery 11, the PWC-ECU 502 sets the inlet 81 to a connector lock state, and the HV-ECU 50 sets the charging relay 83 and the SMR 14 to a closed state (connected state) before the start of external charging. The PWC-ECU 502 then starts external charging of the main battery 11 through four steps (see FIG. 3) described below. During external charging, the CHG-ECU 503 controls the power conversion circuit 82 to adjust the charging power of the main battery 11. When external charging is completed, the CHG-ECU 503 requests the EVSE 400 to stop power supply, and controls the power conversion circuit 82 to stop charging the main battery 11. After that, the HV-ECU 50 opens the charging relay 83 and the SMR 14 (disconnects them), and the PWC-ECU 502 puts the inlet 81 into a connector unlock state. This allows the user to remove the connector 430 from the inlet 81.

In this embodiment, power is supplied to each ECU from an ECU power supply mounted on the vehicle 100. The ECU power supply may be the main battery 11 or an auxiliary battery (not shown). For example, power stepped down from the main battery 11 through a DC/DC converter (not shown) may be supplied to each ECU. Alternatively, power may be supplied to each ECU from the auxiliary battery.

When the vehicle 100 is parked, each ECU included in the vehicle 100 is in a stopped state (for example, in a sleep state). However, when the connector 430 is connected to the inlet 81 (i.e., when the PWC-ECU 502 receives a signal indicating plugging in from the connection sensor 81b), the PWC-ECU 502 is started (i.e., returns to an operating state from a sleep state). Then, the started PWC-ECU 502 puts the inlet 81 into a connector lock state. After that, the PWC-ECU 502 executes a predetermined process in each of the first to fourth steps described below. FIG. 3 is a diagram for explaining the error determination executed by the PWC-ECU 502 when external charging of the main battery 11 starts. In this embodiment, the PWC-ECU 502 corresponds to the "target control device", and each of the HV-ECU 50, the BAT-ECU 501, and the CHG-ECU 503 corresponds to the "other control devices".

Referring to FIG. 3 together with FIG. 1 and FIG. 2, the PWC-ECU 502 starts external charging of the main battery 11 through a first step of turning on the power of other ECUs involved in charging control, a second step of requesting battery information from the BAT-ECU 501, a third step of requesting charging permission from the HV-ECU 50, and a fourth step of sending a charging command to the CHG-ECU 503.

The PWC-ECU 502 is configured to determine the presence or absence of an error for each step. In this embodiment, the PWC-ECU 502 performs an error determination before processing each of the first to fourth steps. Hereinafter, the error determinations before processing the first, second, third, and fourth steps are referred to as the "first error determination," the "second error determination," the "third error determination," and the "fourth error determination," respectively.

In the first error determination, the PWC-ECU 502 determines whether at least one of the following errors has occurred: a plug-in error in which the connector 430 (charging plug) is not properly connected to the inlet 81, and a power supply error in which power is not normally supplied from the EVSE 400 (power source outside the vehicle) to the vehicle 100. If at least one of the errors has occurred, the PWC-ECU 502 determines that an error has occurred. On the other hand, if neither error has occurred, the PWC-ECU 502 determines that there is no error (no error has occurred). The PWC-ECU 502 may determine that a plug-in error has occurred if the inlet 81 does not enter a connector lock state even when the actuator is instructed to drive a lock mechanism (for example, the lock pin 81a shown in FIG. 2). The PWC-ECU 502 may determine that a power supply error has occurred if an external power source PG (for example, a power system) is experiencing a power outage.

If the first error determination determines that there is no error, the PWC-ECU 502 executes the above-mentioned process in the first step (powering on other ECUs involved in charging control). In this embodiment, the HV-ECU 50, the BAT-ECU 501, and the CHG-ECU 503 correspond to the other ECUs involved in charging control. Powering on means putting a stopped ECU into an active state. When a stopped ECU receives an activation signal, it becomes active. In the first step, the PWC-ECU 502 first sends an activation signal to the HV-ECU 50, thereby turning on the power of the HV-ECU 50. Furthermore, the PWC-ECU 502 requests the activated HV-ECU 50 to power on the BAT-ECU 501 and the CHG-ECU 503. Hereinafter, this request will also be referred to as an "IGB-ON request." In response to the IGB-ON request, the HV-ECU 50 sends a start-up signal to each of the BAT-ECU 501 and the CHG-ECU 503. This starts up each of the BAT-ECU 501 and the CHG-ECU 503.

After the processing of the first step, a second error determination is performed. In the second error determination, the PWC-ECU 502 determines whether the vehicle 100 is in a parked state. If the vehicle 100 is not in a parked state, the PWC-ECU 502 determines that an error has occurred. The PWC-ECU 502 also determines that an error has occurred if there is an abnormality in the power supply system of another ECU (i.e., if the PWC-ECU 502 cannot power on at least one of the HV-ECU 50, the BAT-ECU 501, and the CHG-ECU 503). On the other hand, if the vehicle 100 is in a parked state and no abnormality has occurred in the power supply system, the PWC-ECU 502 determines that there is no error. The PWC-ECU 502 may determine whether the vehicle 100 is in a parked state based on at least one of the vehicle speed, the shift range, and the state of the parking brake.

If the second error determination determines that there is no error, the PWC-ECU 502 executes the above-mentioned process in the second step (requesting battery information from other ECUs). The battery information is information indicating the state of the main battery 11 (for example, temperature, current, voltage, SOC, and internal resistance). In the charging system 1, the BAT-ECU 501 is configured to acquire battery information based on the detection results of the voltage sensor 12a, the current sensor 12b, and the temperature sensor 12c. In the second step, the PWC-ECU 502 requests battery information from the BAT-ECU 501. Hereinafter, this request is also referred to as a "start request." In response to the start request, the BAT-ECU 501 transmits the battery information to the PWC-ECU 502.

After the processing of the second step, a third error determination is performed. In the third error determination, the PWC-ECU 502 determines whether or not an abnormality that prevents the start of charging has occurred in the vehicle 100. If an abnormality has occurred in the vehicle 100 (i.e., charging cannot be started due to a vehicle factor), the PWC-ECU 502 determines that an error has occurred. The PWC-ECU 502 also determines that an error has occurred if an abnormality has occurred in the communication between the HV-ECU 50 and the BAT-ECU 501 (i.e., the HV-ECU 50 cannot obtain battery information from the BAT-ECU 501). On the other hand, if no abnormality has occurred in the vehicle 100 and no communication abnormality has occurred, the PWC-ECU 502 determines that no error has occurred. The PWC-ECU 502 may determine that an abnormality that prevents the start of charging has occurred in the vehicle 100 if the state of the main battery 11 is abnormal (for example, if the main battery 11 is in an excessively high temperature state).

If the third error determination determines that there is no error, the PWC-ECU 502 executes the above-mentioned process in the third step (requesting other ECUs for charging permission). In the third step, the PWC-ECU 502 requests the HV-ECU 50 to permit charging. Hereinafter, this request is also referred to as a "start request." In response to the start request, the HV-ECU 50 checks the status of various controls in the vehicle 100 and determines whether or not to permit external charging of the main battery 11. For example, if a control that has priority over charging control (e.g., driving control) is running and it is not possible to transition to charging control, the HV-ECU 50 transmits a signal to the PWC-ECU 502 indicating that external charging of the main battery 11 is not permitted. On the other hand, if only a control that has a lower priority than charging control is running, the HV-ECU 50 stops that control as necessary and transmits a signal to the PWC-ECU 502 indicating that external charging of the main battery 11 is permitted. In this way, the HV-ECU 50 mediates between charging control and other controls. Because the HV-ECU 50 is connected to each of the motor ECU 23, engine ECU 33, BAT-ECU 501, and PWC-ECU 502 so that it can communicate with them, it can efficiently mediate between various controls.

After the processing of the third step, a fourth error determination is made. In the fourth error determination, the PWC-ECU 502 determines whether or not charging permission has been obtained from the HV-ECU 50. The PWC-ECU 502 determines that an error has occurred if charging permission has not been granted in response to the processing (request) of the third step. The PWC-ECU 502 also determines that there is no error if charging permission has been granted through the processing (request) of the third step.

If the fourth error determination determines that there is no error, the PWC-ECU 502 executes the above-mentioned process in the fourth step (sending a charging command to other ECUs). In the fourth step, the PWC-ECU 502 sends a charging command to the CHG-ECU 503. This starts external charging of the main battery 11. During external charging, a charging command is continuously sent from the PWC-ECU 502 to the CHG-ECU 503. The charging command includes a command value for the charging power of the main battery 11. The PWC-ECU 502 calculates the charging power (command value) based on the battery information obtained from the BAT-ECU 501. The CHG-ECU 503 controls the power conversion circuit 82 so that the charging power of the main battery 11 becomes the magnitude (command value) instructed by the PWC-ECU 502. During external charging, the PWC-ECU 502 obtains the latest battery information from the BAT-ECU 501 and calculates the charging power (command value), and the CHG-ECU 503 controls the power conversion circuit 82 according to the charging command from the PWC-ECU 502.

Figure 4 shows the flow of the above-mentioned processing executed by each ECU when external charging of the main battery 11 starts.

Referring to Figure 4 together with Figures 1 to 3, when the connector 430 (charging plug) of the charging cable 420 connected to the EVSE 400 is connected to the inlet 81 (S11), the PWC-ECU 502 is started up. The started PWC-ECU 502 then performs a first error determination (S12). If the first error determination determines that there is no error, the PWC-ECU 502 turns on the power to the HV-ECU 50 and sends an IGBT-ON request to the HV-ECU 50 (S13). S13 corresponds to the first step. The PWC-ECU 502 then performs a second error determination (S14). If the second error determination determines that there is no error, the PWC-ECU 502 makes a start request to the BAT-ECU 501 (S15), and the PWC-ECU 502 acquires battery information from the BAT-ECU 501 (S16). S15 corresponds to the second step. After that, the PWC-ECU 502 makes a third error determination (S17). If the third error determination determines that there is no error, the PWC-ECU 502 makes a start request to the HV-ECU 50 (S18). S18 corresponds to the third step. After that, the PWC-ECU 502 makes a fourth error determination (S20). If the HV-ECU 50 permits external charging of the main battery 11 (S19), the fourth error determination determines that there is no error, and the HV-ECU 50 transmits a charge command to the CHG-ECU 503 (S21). S21 corresponds to the fourth step.

Referring again to FIG. 3 together with FIG. 1 and FIG. 2, when it is determined that an error has occurred in any of the first to fourth error determinations, the PWC-ECU 502 records error information indicating in which of the first to fourth steps it has been determined that an error has occurred. The error information is stored in a storage device of the PWC-ECU 502.

Furthermore, even after external charging of the main battery 11 has begun, the PWC-ECU 502 performs the same determinations as the first to fourth error determinations described above while the main battery 11 is being charged. Hereinafter, this error determination during charging is also referred to as the "fifth error determination." If an error occurs during charging that prevents charging from continuing, the fifth error determination determines that an error has occurred. If the fifth error determination determines that an error has occurred, the PWC-ECU 502 records error information indicating that an error has occurred during external charging of the main battery 11. In this case, too, the error information is saved in the storage device of the PWC-ECU 502. Hereinafter, recording error information when the first, second, third, fourth, and fifth error determinations determine that an error has occurred is referred to as the "first record," "second record," "third record," "fourth record," and "fifth record," respectively.

For example, an error flag may be prepared in advance in the storage device of the PWC-ECU 502. Then, the PWC-ECU 502 may record the error information by updating the value of the error flag. In this embodiment, the first record, the second record, the third record, the fourth record, and the fifth record update the values of the error flag to "1", "2", "3", "4", and "5", respectively. The value of the error flag being "0" (initial value) means that no error has occurred. The value of the error flag being "1" indicates that an error has occurred before (at the start of) the processing of the first step. The value of the error flag being "2" indicates that an error has occurred after the processing of the first step and before the processing of the second step. The value of the error flag being "3" indicates that an error has occurred after the processing of the second step and before the processing of the third step. The value of the error flag being "4" indicates that an error has occurred after the processing of the third step and before the processing of the fourth step. The value of the error flag being "5" indicates that an error has occurred after the processing of the fourth step. In this way, the error information (for example, the value of the error flag above) indicates at what step the error occurred.

If it is determined that an error exists in any of the first to fourth error determinations, the PWC-ECU 502 does not start external charging of the main battery 11. In this case, the PWC-ECU 502 controls a predetermined notification device (for example, at least one of a display device, a lamp, and a speaker, not shown) mounted on the vehicle 100 to notify the user that charging cannot be started. At this time, the PWC-ECU 502 may change the content of the notification (for example, a message) to the user depending on the value of the error flag. Also, if it is determined that an error exists in the fifth error determination, the PWC-ECU 502 stops external charging of the main battery 11. In this case, the PWC-ECU 502 controls the predetermined notification device to notify the user that external charging has been stopped. The PWC-ECU 502 may cause a mobile terminal carried by the user of the vehicle 100 to make the notification.

The error information recorded in the PWC-ECU 502 can be read out, for example, by a specified service tool. The error information may be used in OBD (self-diagnosis). By recording such error information, for example, a user or a maintenance company (including a repair company) can easily understand at what step the error occurred, and can easily identify the cause of the error. The PWC-ECU 502 may also transmit the error information. For example, the PWC-ECU 502 may transmit the error information to a server (not shown) of the automobile manufacturer. In this form, the automobile manufacturer can replace vehicle parts or provide the user with advice on how to use the vehicle based on the error information.

As described above, the PWC-ECU 502 is configured to monitor the sequence before the start of charging and detect the phase at which the charge start control has progressed when an error has occurred. Specifically, the charging system 1 according to this embodiment includes the PWC-ECU 502 (control device) that starts charging the main battery 11 (electricity storage device) through multiple steps (first to fourth steps) before charging the main battery 11. Each of the first to fourth steps is a step in which the PWC-ECU 502 executes a process involving communication with another ECU (another control device). The PWC-ECU 502 is configured to determine whether or not an error has occurred in each of the first to fourth steps (first to fourth error determinations). When it is determined that an error has occurred, the PWC-ECU 502 is configured to record error information indicating in which of the first to fourth steps it has been determined that an error has occurred (first to fourth records).

Charging systems that perform error determination when external charging starts are known, but in known charging systems, the error determination function is distributed and installed in multiple ECUs. In such charging systems, although it is possible to determine whether external charging can be started, it is difficult to analyze the cause of an error. In contrast, in the above embodiment, the error determination function is consolidated in the PWC-ECU 502, which enables the PWC-ECU 502 to perform error determination for each step in the control for starting external charging of the main battery 11. The PWC-ECU 502 monitors each of the state of the inlet 81 and the state of the main battery 11, and performs error determination while communicating with other ECUs. By communicating with other ECUs, the PWC-ECU 502 can check the presence or absence of errors not only in the control range of the PWC-ECU 502 but also in the control range of the other ECUs. Therefore, the PWC-ECU 502 can check the presence or absence of various errors (including communication errors) that may occur during charging before starting charging. This configuration makes it possible to record more detailed error information in the PWC-ECU 502.

The number of steps in the sequence before charging starts (more specifically, steps that execute processes involving communication between control devices) is not limited to four and can be any number equal to or greater than two. The number of steps may be increased or decreased as appropriate.

In the above embodiment, when the vehicle 100 changes from a driving state to a parked state, the PWC-ECU 502 is stopped, and the PWC-ECU 502 is activated by plugging in. However, this is not limited to the above, and the PWC-ECU 502 may not be stopped even when the vehicle 100 is parked, and the PWC-ECU 502 may always remain in operation when the vehicle is parked.

The configuration of the vehicle is not limited to the configuration shown in FIG. 1. For example, in the above embodiment, the vehicle is configured to be capable of charging the power storage device with AC (alternating current) power supplied from outside the vehicle. However, the vehicle may be configured to be capable of charging the power storage device with DC (direct current) power supplied from outside the vehicle. The vehicle may receive power from a DC-type EVSE (EVSE that outputs direct current power). The power conversion circuit (charger) may be mounted on the EVSE instead of the vehicle. The vehicle may also be configured to be capable of non-contact charging (wireless charging). A control device mounted on such a vehicle may perform the above-mentioned error determination before the start of non-contact charging.

The vehicle may be an EV (electric vehicle) that does not have an engine (internal combustion engine). The vehicle is not limited to a passenger car, but may be a bus or a truck. The vehicle may be configured to be capable of unmanned driving by automatic driving or remote driving. The vehicle may be an automated guided vehicle (AGV).

The application of the charging system is not limited to vehicles. The charging system can be applied to any medium (e.g., a moving object, a robot, a stationary device, a portable device, or a building) that has multiple control devices and a chargeable power storage device. The charging system may be installed in vehicles other than vehicles (ships, airplanes, etc.), unmanned moving objects (automated guided vehicles (AGVs), agricultural machinery, walking robots, drones, robot cleaners, space probes, etc.), wearable robots (e.g., nursing robots), stationary robots (e.g., industrial robots), household electrical appliances (air conditioners, cooking utensils, televisions, refrigerators, washing machines, etc.), portable devices (smartphones, wearable devices, etc.), or buildings (houses, factories, etc.).

The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is indicated by the claims rather than by the description of the embodiments above, and is intended to include all modifications within the meaning and scope of the claims.

1 Charging system, 11 Main battery, 12a Voltage sensor, 12b Current sensor, 12c Temperature sensor, 21a First motor generator, 21b Second motor generator, 23 Motor ECU, 31 Engine, 33 Engine ECU, 50 HV-ECU, 501 BAT-ECU, 502 PWC-ECU, 503 CHG-ECU, 81 Inlet, 82 Power conversion circuit, 100 Vehicle, 400 EVSE, PG External power source.

Claims (3)

A charging system including a control device that starts charging of a power storage device through a plurality of steps before charging the power storage device,
Each of the steps is a step in which the control device executes a process involving communication with another control device,
The steps include:
a first step of the control device turning on the power of the other control device involved in charging control;
a second step of the control device requesting information indicating a state of the power storage device from the other control device;
a third step in which the control device requests permission for charging from the other control device;
a fourth step of the control device transmitting a charging command to the other control device;
Including,
the control device is configured to perform an error determination to determine whether or not an error exists before each of the first to fourth steps;
The control device is configured to record error information indicating in which of the first to fourth steps it is determined that an error has occurred when it is determined that an error has occurred in any of the error determinations before processing each of the first to fourth steps. The control device includes:
If it is determined that there is no error in the error determination before the processing of the first step, the process proceeds to the first step and the power supply of the other control device is turned on;
When it is determined that there is no error in the error determination before the processing of the second step, the second step is performed to request information indicating a state of the power storage device from the other control device;
When it is determined that there is no error in the error determination before the processing of the third step, the process proceeds to the third step, and a request for the charging permission is made to the other control device;
If it is determined that there is no error in the error determination before the processing of the fourth step, the process proceeds to the fourth step, and the charging command is transmitted to the other control device;
2. The charging system according to claim 1, configured not to start charging the power storage device when it is determined that an error has occurred in any of the error determinations before the processing of each of the first to fourth steps. The charging of the power storage device is external charging in which the power storage device mounted on the vehicle is charged using electric power supplied from a power source external to the vehicle,
In the error determination before the processing of the first step, it is determined that an error has occurred when a charging plug is not properly connected to an inlet of the vehicle,
In the error determination before the processing of the second step, it is determined that an error has occurred when the vehicle is not in a parked state,
In the error determination before the processing of the third step, it is determined that an error has occurred when an abnormality that prevents the start of charging has occurred in the vehicle,
3 . The charging system according to claim 1 , wherein, in the error determination before the processing of the fourth step, it is determined that an error has occurred if the charging permission has not been received in the processing of the third step. 4 .

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