JP7848601B2 - Charge/discharge control method and charge/discharge apparatus - Google Patents

Description

The present invention relates to a charge/discharge control method and a charge/discharge device for controlling the charging and discharging of a storage battery installed in a vehicle.

The batteries in electric vehicles (EVs) have relatively large capacities. Technologies have been proposed to realize V2H (Vehicle to Home), which allows the stored power in these vehicles to be used not only for driving the EVs themselves, but also for supplying power to household loads, for example. Beyond V2H, technologies have also been proposed to realize V2X, including V2B (Vehicle to Building), which enables power supply to larger buildings, and V2G (Vehicle to Grid), which enables power supply to the power grid. These technologies are expected to allow for the maintenance of daily life and the continued operation of factories by supplying power stored in mobile electric vehicles, even in the event of a power outage caused by a disaster.

To realize V2X (Vehicle-to-X) power using the batteries installed in electric vehicles and to promote the widespread adoption of electric vehicles, it is necessary not only for electric vehicle owners and dealers to prepare dedicated charging and discharging equipment for their vehicles, but also for the expansion of general-purpose charging stations. Such widely used general-purpose charging stations require charging and discharging equipment capable of handling a wide variety of vehicles.

While the charging and discharging of electric vehicles are controlled according to certain standards such as CHAdeMO (registered trademark), the behavior differs slightly depending on the vehicle manufacturer and model. Therefore, general-purpose charging and discharging devices implement charge and discharge control tailored to the vehicle model (e.g., Patent Document 1).

Patent No. 6737390

The charging and discharging device can control the vehicle's battery based on instructions from a higher-level system such as a HEMS (Home Energy Management System). The higher-level system acquires data about the vehicle's battery, such as its charge and discharge capacity, from the charging and discharging device. Based on this data, it controls charging and discharging according to the power consumption of the connected load and the amount of power generated by the power generation system, or controls it according to a schedule.

The host system may frequently attempt to acquire data from the vehicle connected via the charge/discharge unit, depending on the situation. The connection between the charge/discharge unit and the vehicle is performed in a sequence that conforms to a predetermined standard. Each time the host system attempts to acquire data while the vehicle is in standby mode (not charging or discharging), the charge/discharge unit performs the connection sequence with the vehicle. This causes the vehicle to start up even if it is in a standby (stopped) state, consuming power for startup. An excessive increase in the frequency of startups will increase the vehicle's power consumption.

This invention has been made in view of these circumstances, and aims to provide a charge/discharge control method and a charge/discharge device that appropriately respond to inquiries from a higher-level device to a vehicle.

A charge/discharge device according to one embodiment of the present disclosure is connected to an on-board battery installed in a vehicle and controls charging and discharging between the on-board battery and a power source or load. The device comprises: a vehicle communication unit that communicates with an on-board control device that controls charging and discharging of the on-board battery on the vehicle side; a higher-level communication unit that communicates with a higher-level device; and a control unit that, after acquiring data related to the on-board battery from the on-board control device via the vehicle communication unit and storing the data, responds to the data acquisition instruction for the on-board battery from the higher-level device before charging and discharging begins, while the vehicle is connected to the charge/discharge device, based on the stored data.

A charge/discharge control method according to one embodiment of the present disclosure is a control method for a charge/discharge device connected to an on-board battery that serves as a DC power source in a vehicle, and which controls charging and discharging between the on-board battery and a power source or load. The charge/discharge device comprises a vehicle communication unit that communicates with an on-board control device that controls charging and discharging of the on-board battery on the vehicle side, and a higher-level communication unit that communicates with a higher-level device. The charge/discharge device acquires data related to the on-board battery from the on-board control device via the vehicle communication unit, stores the data, and, before charging and discharging begin, receives a data acquisition instruction for the on-board battery from the higher-level device. While the vehicle is connected to the charge/discharge device, the charge/discharge device responds to the data acquisition instruction based on the stored data.

In the charging/discharging device and charging/discharging control method of this disclosure, even if a data acquisition instruction is received from a higher-level device, as long as the same vehicle is connected to the charging/discharging device, the device will respond based on data acquired and stored after establishing a communication connection.

This eliminates the need to perform a predetermined connection sequence that involves establishing a communication connection with the vehicle and activating it each time a data acquisition instruction is received from a higher-level device. In other words, it eliminates the unnecessary process of activating a standby vehicle each time, even when it is clear that the same data will be acquired.

In one embodiment of the charge/discharge device of this disclosure, if a charge/discharge stop instruction is given before the start of charge/discharge, the control unit erases the stored data. Upon receiving the data acquisition instruction again, it acquires the data from the on-board control device via the vehicle communication unit and responds to the data acquisition instruction.

In the charge/discharge device of this disclosure, stored data is erased only when a command to stop charging/discharging is issued before charging/discharging begins. Otherwise, even if a data acquisition command is received before charging/discharging begins, the device will respond with the stored data, avoiding starting the vehicle. Furthermore, a higher-level device may read vehicle information before charging/discharging begins, put the charge/discharge device into a standby state, and, based on the vehicle information, may stop charging/discharging without actually charging or discharging. In this case, by responding with the retained data until the charge/discharge device stops, it is possible to avoid the repeated execution of a predetermined sequence associated with connecting to the vehicle before the charge/discharge device stops.

In one embodiment of the charging and discharging device of this disclosure, if the lock of the connector connected to the vehicle is turned OFF before charging and discharging begins, the control unit erases the stored data. Upon receiving the data acquisition instruction again, it acquires the data from the on-board control device via the vehicle communication unit and responds to the data acquisition instruction.

In the charging and discharging device of this disclosure, it is determined that the same vehicle may not be connected only when the connector lock is turned OFF before charging and discharging begins. Until the connector lock is turned OFF, even if a data acquisition command is received before charging and discharging begins, the device can respond with stored data and avoid starting the vehicle.

In one embodiment of the charge/discharge device of this disclosure, the control unit, if a stop operation is performed before the start of charging/discharging, erases the stored data. When it receives the data acquisition instruction again, it acquires the data from the on-board control device via the vehicle communication unit and responds to the data acquisition instruction. While the device is in a standby state after reading vehicle information before the start of charging/discharging, the user may decide to stop the device without charging/discharging. In this case, by responding with the data held until the stop operation is performed, it is possible to avoid the repeated execution of a predetermined sequence associated with connecting to the vehicle before stopping.

In the charging and discharging device of this disclosure, it is determined that the same vehicle may not be connected only when a stop operation is performed before the start of charging and discharging. Until a stop operation is performed, even if a data acquisition instruction is received before the start of charging and discharging, the device can respond with stored data and avoid starting the vehicle.

In one embodiment of the charging and discharging apparatus of this disclosure, the control unit responds to the data acquisition instruction based on stored data while the lock of the connector connected to the vehicle is ON before the start of charging and discharging.

In the charging and discharging device of this disclosure, while the connector lock is ON before charging and discharging begins, it is determined that the same vehicle remains connected, and in response to a data acquisition command, it responds with stored data, thus avoiding starting the vehicle.

In a charge/discharge device according to one embodiment of this disclosure, the control unit responds to the data acquisition instruction based on stored data without initiating a connection with the on-board control device, if the frequency of receiving the data acquisition instruction is above a predetermined frequency.

The charging and discharging device of this disclosure can avoid repeatedly starting the vehicle when data acquisition instructions are issued frequently.

In a charge/discharge device according to one embodiment of the present disclosure, the control unit determines whether the same vehicle is connected, and if it is determined that the same vehicle is connected, it responds to the data acquisition instruction based on stored data without initiating a connection with the on-board control device.

The charging and discharging device of this disclosure, when it is clear that the same vehicle remains connected, can respond based on stored data, unless the situation changes, thereby avoiding unnecessarily starting the vehicle.

According to this disclosure, it is possible to avoid performing a predetermined sequence of connections that involves establishing a communication connection with the vehicle and starting the vehicle each time a data acquisition instruction is received from a higher-level device, and to respond appropriately with the necessary information.

This is a schematic diagram of a charge/discharge system, including the charge/discharge device. This is a block diagram showing the connection configuration of the charging/discharging device and the vehicle. This flowchart shows an example of a processing procedure in a charging and discharging device. This flowchart shows an example of a processing procedure in a charging and discharging device. This flowchart shows an example of the processing procedure for the charging and discharging device in Modification Example 1. This flowchart shows an example of the processing procedure for the charging and discharging device in Modification Example 1. This flowchart shows an example of the processing procedure for the charge/discharge device in modified example 2. This flowchart shows an example of the processing procedure for the charge/discharge device in modified example 2. This flowchart shows an example of the processing procedure in the charge/discharge device of the second embodiment. This flowchart shows an example of the processing procedure in the charge/discharge device of the second embodiment. This flowchart shows an example of a processing procedure in the charge/discharge device of the third embodiment. This flowchart shows an example of a processing procedure in the charge/discharge device of the third embodiment. This flowchart shows an example of a processing procedure in a charge/discharge device of a modified example of the third embodiment. This flowchart shows an example of a processing procedure in a charge/discharge device of a modified example of the third embodiment. This is a block diagram showing the configuration of the charge/discharge device according to the fourth embodiment. This flowchart shows an example of the processing procedure in the charge/discharge device of the fourth embodiment. This flowchart shows an example of the processing procedure in the charge/discharge device of the fourth embodiment.

This disclosure will be specifically described with reference to the drawings illustrating its embodiments.

(First Embodiment)
Figure 1 is a schematic diagram of a charge/discharge system 200 including a charge/discharge device 1. The charge/discharge system 200 includes the charge/discharge device 1 and loads 21 of buildings such as homes and businesses that use the electricity supplied through the charge/discharge device 1. The charge/discharge system 200 is connected to a power grid E, which is the power source, by a power line PL. The power source is not limited to power grid E, but may also be a DC power grid. The power supplied from the power source is branched to the loads 21 and the charge/discharge device 1 at a distribution board 28. The charge/discharge system 200 may also include a configuration that includes multiple charge/discharge devices 1 installed in a parking lot of a public facility. The charge/discharge system 200 may also include a fuel cell.

A vehicle V, which has a built-in energy storage device, is connected to the charging/discharging device 1. The vehicle V's energy storage device can be charged, and the vehicle V's energy storage device can also be used as a power source to supply power to the load 21. As shown in Figure 1, the charging/discharging system 200 may include not only the charging/discharging device 1 and the load 21, but also interconnection devices such as an energy storage device 22 or a power generation device 23.

The charging/discharging device 1 is connected to a higher-level device 29 installed in the distribution panel 28 via a communication line CL. The higher-level device 29 is, for example, a HEMS controller. The higher-level device 29 is not limited to a HEMS controller, but is a device that controls power in equipment in the vehicle V, including the energy storage device, load 21, and interconnection devices 22, 23, etc., connected via the charging/discharging device 1. The higher-level device 29 controls the transfer of power from the power source to the load 21, the transfer of power from the power generation device 23 to the group of loads 21, and the charging and discharging of the vehicle V to the charging/discharging device 1. The higher-level device 29 may be a server device located outside the system, controlling the transfer of power for the entire region, or it may be built into each charging/discharging device 1, controlling the charging and discharging of the vehicle V's batteries.

Figure 2 is a block diagram showing the connection configuration between the charging/discharging device 1 and the vehicle V. The vehicle V is an electric vehicle (EV), a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), or a fuel cell vehicle (FCV).

Vehicle V is equipped with a large-capacity energy storage device 30 that can be used for its propulsion. Vehicle V is also equipped with a connector 35 to a power line VPL connected to the energy storage device 30, and an on-board control device 32 that controls charging and discharging in the energy storage device 30. A DC relay 33, included in the charging and discharging circuit on the vehicle V side, is interposed in the power line VPL, and the on-board control device 32 controls the ON and OFF states of the DC relay 33. The connector 35 includes a communication terminal for communication connection with the on-board control device 32.

The charging/discharging device 1 comprises a charging/discharging circuit 10, a control unit 11, a vehicle communication unit 12, a power supply unit 13, an operation unit 14, and a higher-level communication unit 16. The charging/discharging circuit 10 includes various circuit elements such as a bidirectional inverter and various relays. The charging/discharging circuit 10 includes a DC relay 10a connected to a connector 15 connected to the vehicle V, and a disconnection relay 10b interposed in the power line PL connected to the power system E. The charging/discharging circuit 10 is connected to the connector 15 and the power line PL via the DC relay 10a.

The control unit 11 controls the circuit elements included in the charge/discharge circuit 10, and controls the switching between charging and discharging, the amount of current, and the amount of voltage for the vehicle V's energy storage device 30. The control unit 11 includes a CPU (Central Processing Unit) and non-volatile memory. The CPU controls the charge/discharge circuit 10 by executing control processing based on the computer program 1P stored in the non-volatile memory.

The computer program 1P stored in the non-volatile memory of the control unit 11 may be a computer program 9P that was stored on a storage medium 9 read by the computer and then stored in memory by the CPU.

The vehicle communication unit 12 can communicate with the on-board control device 32 via connectors 15 and 35. The communication protocol of the vehicle communication unit 12 only needs to conform to the charging and discharging methods corresponding to the vehicle V and connectors 15 and 35. It may also support multiple protocols and selectively execute one of them to apply to different charging and discharging methods. In this embodiment, the vehicle communication unit 12 communicates with the on-board control device 32 via CAN (Controller Area Network). Communication may also be implemented via PLC (Power Line Communication).

The power supply unit 13 includes a UPS (Uninterruptible Power Systems) circuit and a starting battery, and supplies power to the control unit 11. In the event of a power outage, the power supply unit 13 supplies the power necessary to start the charge/discharge device 1 from the starting battery. The power supply unit 13 may also charge the starting battery with power from the power grid E, the power generator 23, or the vehicle V.

The operation unit 14 includes a display, a touch panel with an integrated display, and physical buttons. The operation unit 14 is exposed on the exterior of the charge/discharge device 1 and receives touch panel operations from the user. The operation unit 14 receives various buttons, including a start button and a stop button, on the touch panel. The start and stop buttons may be physical buttons instead of touch panel buttons. The operation unit 14 may be configured to be isolated from the main body of the charge/discharge device 1; for example, it may be configured as a remote controller within a building. The operation unit 14 may also be configured to receive operation information received via wireless communication from the operation interface of a communication terminal such as a smartphone or tablet held by the user (or administrator). The control unit 11 executes the reservation processing described later based on the operations received by the operation unit 14. The operation unit 14 may include lamps, which may be controlled by the control unit 11 to light up in a color or pattern according to the state.

The higher-level communication unit 16 communicates with the higher-level device 29 via a communication line CL or via wireless communication. The higher-level communication unit 16 is, for example, a communication module compatible with an ECHONET/ECHONET Lite (registered trademark) communication line CL. The higher-level communication unit 16 may also be a communication module compatible with an Ethernet (registered trademark) communication line CL, or it may implement communication using a PLC. The higher-level communication unit 16 may also be a wireless communication module compatible with WiFi (registered trademark), Bluetooth (registered trademark), or carrier communication.

As described above, the charge/discharge circuit 10 of the charge/discharge device 1 is connected to the vehicle V's energy storage device 30 via a power line PL through a DC relay 10a and a DC relay 33 on the vehicle V side, as shown in Figures 1 and 2, when the connector 15 is connected to the vehicle V's connector 35. The charge/discharge circuit 10 is connected to the power system E and interconnection equipment (energy storage device 22, power generation device 23, etc.) via a power line PL through a disconnection relay 10b and a distribution board 28, as shown in Figures 1 and 2. The charge/discharge device 1 controls the exchange of power between the power system E and the vehicle V's energy storage device 30 and interconnection equipment. When the disconnection relay 10b, DC relay 10a, and DC relay 33 are all ON, the charge/discharge circuit 10 can discharge the energy storage device 30 to the energy storage device 22 or load, or charge the energy storage device 30 from the power system E, via the power line PL. The control unit 11 of the charge/discharge device 1 executes a predetermined connection sequence with the on-board control device 32 before performing charge/discharge, thereby enabling the start of charge/discharge. This predetermined connection sequence between the charge/discharge device 1 and the on-board control device 32 is defined, for example, in charge/discharge control standards such as CHAdeMO (registered trademark).

The control unit 11 of the charge/discharge device 1 controls the charge/discharge circuit 10 in a selectable mode for charging or power supply (discharging from the energy storage device 30) based on user input to the operation unit 14. Alternatively, the control unit 11 controls power supply in an independent power supply mode when power supply from the power system E is interrupted (power outage). Furthermore, the control unit 11 controls the charge/discharge circuit 10 in an EMS mode, which performs charging or power supply in response to instructions from the higher-level device 29 based on user or administrator input to the operation unit 14.

In the following description, the charging/discharging device 1 will be described in terms of its EMS mode, which controls the charging/discharging circuit 10 in response to instructions from the higher-level device 29. In EMS mode, where control is performed in response to instructions from the higher-level device 29, the control unit 11 of the charging/discharging device 1 communicates with the higher-level device 29 and transmits data exchanged with the on-board control device 32 to the higher-level device 29 as appropriate. Based on these instructions from the higher-level device 29, the control unit 11 controls the charging/discharging circuit 10.

Figures 3 and 4 are flowcharts illustrating an example of the processing procedure in the charge/discharge device 1. The processing procedure shown in the flowcharts of Figures 3 and 4 is an example of the process from the start of output in EMS mode in response to instructions from the host device 29. The control unit 11 of the charge/discharge device 1, operating in EMS mode in response to instructions from the host device 29 as described above, executes the following processing procedure.

When the control unit 11 is activated by the power breaker being turned ON, a startup instruction from the host device 29, an instruction from the operation unit 14, or the start of power supply from the power supply unit 13 based on a schedule (step S101), it notifies the host device 29 that it is in a stopped state before communication connection with the vehicle V (step S102).

The control unit 11 determines, in the stopped state, whether the start button was selected on the operation unit 14 or whether a vehicle connection confirmation instruction was received from the host device 29 (step S103). If, in step S103, it is determined that neither the start button was selected nor that there was a vehicle connection confirmation instruction from the host device 29 (S103: NO), the control unit 11 returns to step S103.

In step S103, if it is determined that the start button has been selected or that a vehicle connection confirmation instruction has been received from the host device 29 (S103: YES), the control unit 11 sends a notification of connection commencement or a response to the instruction to the host device 29 (step S104). The control unit 11 starts a predetermined connection sequence for the vehicle V to the on-board control device 32 (step S105). The control unit 11 determines whether a communication connection has been established with the on-board control device 32 by starting the predetermined connection sequence (step S106). If it is determined that a communication connection cannot be established (S106: NO), the control unit 11 cancels the connection sequence (step S107), returns the process to step S102, and enters a stopped state.

If it is determined that a communication connection has been established (S106: YES), the control unit 11 turns ON the locks on connectors 15 and 35 (step S108). The control unit 11 receives vehicle data from the on-board control device 32 and stores it in memory (step S109). The vehicle data includes vehicle identification data (vehicle ID), charging capacity, current charge rate (SOC: State of Charge), lower limit charge rate, upper limit charge rate, charging power, and discharge power, etc.

The control unit 11 stops the connection sequence (step S110), disconnects the communication connection, and enters a standby state (disconnection standby) (step S111).

The control unit 11 notifies the host device 29 that it is in standby mode (step S112), and further determines whether charging and power supply are possible based on the vehicle data received in step S109, and temporarily stores this information (step S113). The control unit 11 then notifies the host device 29 of the determined status (step S114).

In step S113, the control unit 11 stores the total capacity (charging capacity) of the energy storage device 30, the amount of energy that can be discharged from a full charge, the amount of energy that can be charged from an empty state, the amount of energy that can be charged from the current charge level to the upper limit, the amount of energy that can be discharged from the current charge level to the lower limit, and the vehicle ID, based on the vehicle data. In step S114, the control unit 11 notifies the host device 29 of this information.

The control unit 11, in standby mode, determines whether or not a vehicle connection confirmation instruction has been received from the higher-level device 29 (step S115). If it is determined that there is no vehicle connection confirmation instruction (S115: NO), the control unit 11 determines whether or not the stop button has been selected on the operation unit 14 (step S116). If it is determined that the stop button has been selected while in standby mode (S116: YES), the control unit 11 turns OFF the connector lock (step S117) and clears the results of the determination of charging and power supply feasibility from the memory (step S118). The control unit 11 returns to step S102 and enters a stopped state. In some cases, while in standby mode after reading vehicle information before starting charging and discharging, the user may decide to stop without charging or discharging.

If it is determined that the stop button is not selected (S116: NO), the control unit 11 determines whether or not there is a stop instruction from the higher-level device 29 (step S119). If it is determined that there is a stop instruction (S119: YES), the control unit 11 proceeds to step S118. The higher-level device 29 reads the vehicle information before charging and discharging begins, and during the standby state, it may decide, based on the vehicle information, to stop without charging or discharging if necessary.

If it is determined in step S119 that a stop instruction has been given (S119: YES), the control unit 11 may proceed to step S117 and perform the same processing as when the stop button is selected (S117).

If it is determined that there is no instruction to stop (S119: NO), the control unit 11 determines whether there is an instruction to charge or discharge from the host device 29 (step S120). If it is determined that there is an instruction to charge or discharge from the host device 29 (S120: YES), the control unit 11 starts a predetermined connection sequence (step S121) and notifies the host device 29 that charging or discharging has started (step S122).

The control unit 11 turns on the DC relay 10a and the disconnection relay 10b on the charge/discharge device 1 side, and the DC relay 33 on the vehicle V side to start output (step S123), and then finishes the processing before starting output.

If it is determined that there is neither a charging nor a discharging instruction (S120: NO), the control unit 11 returns to step S115.

If, in step S115, it is determined that there is a vehicle connection confirmation instruction (S115: YES), the control unit 11 notifies the higher-level device 29 of the status stored in step S113 (step S124) without returning the process to step S104, and then returns the process to step S115.

In step S124, the control unit 11 will, without again performing communication connection, vehicle data acquisition, and disconnection with the on-board control device 32, will respond to inquiries with the previously determined charging and power supply status as long as the connection with the same vehicle V can be confirmed.

As a result of the processing in steps S115 and S124 described above, the charge/discharge device 1 will not execute the connection sequence with the on-board control device 32, even if it receives a vehicle connection confirmation instruction from the higher-level device 29, as long as the vehicle V is not removed from the charge/discharge device 1 and no significant change in circumstances is expected. As long as it is certain that the same vehicle V is connected, the charge/discharge device 1 only needs to notify the status it has determined. A case where a change in circumstances is expected is, for example, when a predetermined time has elapsed while the device remains in standby mode.

The higher-level device 29 may query the charge/discharge device 1 every few minutes to confirm the vehicle connection and obtain information about the vehicle V's energy storage device 30. If the connection sequence between the charge/discharge device 1 and the on-board control device 32 is repeated each time, the vehicle V would need to start up from a stopped (standby) state multiple times to respond to the query, thus consuming the 12V battery used for starting. In contrast, the charge/discharge device 1, as long as the vehicle V is not removed, can avoid this battery consumption by notifying the determined status without unnecessarily repeating the connection sequence.

After the charging/discharging device 1 executes the processing procedure shown in the flowcharts of Figures 3 and 4, and then starts charging and discharging, if it enters a stopped state, it starts processing from step S101, executes a predetermined connection sequence once, and then, based on the changes in conditions (charge rate, etc.) due to charging and discharging, it determines and stores again the amount of power that can be charged from the current charge rate up to the upper limit and the amount of power that can be discharged from the current charge rate down to the lower limit.

(Variation 1)
If it can be inferred that the vehicle V remains connected, the charge/discharge device 1 can be implemented by other means of processing to avoid unnecessarily repeating the connection sequence. Figures 5 and 6 are flowcharts showing an example of the processing procedure of the charge/discharge device 1 in modified example 1. Of the processing procedures shown in the flowcharts of Figures 5 and 6, those that are common with the processing procedures shown in the flowcharts of Figures 3 and 4 are given the same step numbers and detailed explanations are omitted.

In Modification 1, the control unit 11 is configured to notify the system of the status it has determined as long as the connector lock is ON. Therefore, when the control unit 11 determines that the start button has been selected or that there is a vehicle connection confirmation instruction from the host device 29 (S103: YES), and sends a notification of connection start or a response to the instruction to the host device 29 (S104), it determines whether the connector lock is ON or not (step S131). After a vehicle connection confirmation instruction is received and the locks of connectors 15 and 35 are turned ON once (S108), the processing procedure of steps S102-S111 is repeated in a standby state, and in step S131, the control unit 11 determines that the connector lock is ON.

In step S131, the control unit 11 may, as another method for confirming that the same vehicle V remains connected, determine not only whether the connector lock is ON, but also whether the vehicle connection confirmation line among the signal lines included in the connector 15 can continuously confirm that the vehicle is connected. If the control unit 11 detects that the signal indicating connection on the vehicle connection confirmation line has been interrupted, it can determine in step S131 that the vehicle is not connected.

If it is determined in step S131 that the connector lock is not in the ON state (i.e., it is in the OFF state) (S131: NO), the control unit 11 executes the processing from step S105 onwards.

If the control unit 11 determines in step S131 that the connector lock is ON (S131: YES), it skips the connection sequence (S105-S114, S115) and proceeds to step 132.

In Modified Example 1, if the control unit 11 determines in step S115 that a vehicle connection confirmation instruction has been received while remaining in standby mode (S115: YES), it notifies the higher-level device 29 that it is in standby mode and the stored status (step S132), and then returns the process to step S115.

Furthermore, in Modification 1, if a stop instruction is received in step S119 (S119: YES), the control unit 11 returns to step S102 instead of step S119, and returns to the stopped state (standby state) without clearing the determined status stored in step S113.

Once the locks on connectors 15 and 35 are turned ON, the connected vehicle V remains the same unless the stop button is selected and turned OFF. Therefore, the results of determining whether charging and power supply are possible can be reported to the higher-level device 29 without having to perform the connection sequence multiple times. The processing procedure in Modified Example 1 further reduces the number of times the connection sequence is performed.

(Variation 2)
In Modification 2, the determination of whether charging and power supply are possible is retained in memory until the stop button is selected, and the system responds accordingly. Figures 7 and 8 are flowcharts showing an example of the processing procedure of the charge/discharge device 1 in Modification 2. Of the processing procedures shown in the flowcharts of Figures 7 and 8, those that are common with the processing procedures shown in the flowcharts of Figures 3 and 4 are given the same step numbers, and detailed explanations are omitted.

In Modification 2, when the control unit 11 of the charge/discharge device 1 starts up in response to a start instruction from the host device 29, an instruction from the operation unit 14, or the start of power supply from the power supply unit 13 based on a schedule (S101), it determines whether the stop button has been selected on the operation unit 14 before notifying the stopped state (step S133). If the control unit 11 determines that the stop button has not been selected on the operation unit 14 (S133: NO), it notifies the stopped state (S102).

If the control unit 11 determines that the stop button has been selected in step S133 (S133: YES), it turns off the locks on connectors 15 and 35 if they are ON, and clears the status determined based on vehicle data once it has been connected to vehicle V (step S134). The control unit 11 returns to step S133. Thereafter, unless the stop button is selected again in the standby state, the control unit 11 executes the processes from step S102 onwards.

In the modified example 2, if the control unit 11 determines in step S115 that a vehicle connection confirmation instruction has been received from the host device 29 while remaining in standby mode (S115: YES), it notifies the host device 29 that it is in standby mode and the stored status (step S132), and then returns the process to step S115.

In the modified example 2, if the control unit 11 determines that there is no vehicle connection confirmation instruction from the host device 29 (S115: NO), the control unit 11 determines whether the stop button has been selected on the operation unit 14 or whether there is a stop instruction from the host device 29 (step S135). If the control unit 11 determines that neither the stop button has been selected nor that there is a stop instruction (S135: NO), the process proceeds to step S120.

If the control unit 11 determines that the stop button has been selected on the operation unit 14, or that a stop command has been received from the higher-level device 29 (S135: YES), the control unit 11 returns to step S133. In this case, unless the stop button has been selected, the control unit 11 keeps connectors 15 and 35 locked and does not clear the status it has determined and stored in memory.

In Modification 2, the control unit 11 turns off the connector lock and clears the stored status only when the stop button is selected. When the connector lock is ON, the connection sequence is not repeated, reducing the number of system startups in the vehicle V.

(Second Embodiment)
The configuration of the charge/discharge system 200 in the second embodiment is the same as that of the charge/discharge system 200 in the first embodiment, except for the details of the processing procedure up to the start of charge/discharge which will be described later. Therefore, for the charge/discharge system 200 in the second embodiment that is common with the configuration of the charge/discharge system 200 in the first embodiment, the same reference numerals are used and detailed explanations are omitted.

The processing procedure described in the second embodiment is the procedure up to the start of charging and discharging when the charging/discharging device 1, in EMS mode, maintains a communication connection with the vehicle V and remains in a standby state with the DC relay 10a and DC relay 33 ON, in order to improve responsiveness to instructions from the higher-level device 29.

Figures 9 and 10 are flowcharts illustrating an example of the processing procedure in the charge/discharge device 1 of the second embodiment. The control unit 11 of the charge/discharge device 1, in EMS mode which operates by receiving instructions from the higher-level device 29 as described above, executes the following processing procedure.

When the control unit 11 starts up in response to a startup instruction from the host device 29, an instruction from the operation unit 14, or the start of power supply from the power supply unit 13 based on a schedule (step S201), it notifies the host device 29 that it is in a stopped state before establishing communication with the vehicle V (step S202).

The control unit 11 determines, in the stopped state, whether the start button was selected on the operation unit 14 or whether a vehicle connection confirmation instruction was received from the host device 29 (step S203). If, in step S203, it is determined that neither the start button was selected nor that there was a vehicle connection confirmation instruction from the host device 29 (S203: NO), the control unit 11 returns to step S203.

In step S203, if it is determined that the start button has been selected or that a vehicle connection confirmation instruction has been received from the host device 29 (S203: YES), the control unit 11 sends a notification of connection commencement or a response to the instruction to the host device 29 (step S204). The control unit 11 starts a predetermined connection sequence for the vehicle V to the on-board control device 32 (step S205). The control unit 11 determines whether a communication connection has been established with the on-board control device 32 by starting the predetermined connection sequence (step S206). If it is determined that a communication connection cannot be established (S206: NO), the control unit 11 cancels the connection sequence (step S207), returns the process to step S202, and enters a stopped state.

If it is determined that a communication connection has been established (S206: YES), the control unit 11 turns ON the locks on connectors 15 and 35 (step S208). The control unit 11 receives vehicle data from the in-vehicle control device 32 and stores it in memory (step S209). The vehicle data includes vehicle identification data (vehicle ID), charging capacity, current charge level (SOC), lower limit charge level, upper limit charge level, upper limit charging current, minimum charging current, and upper limit discharge current, etc.

The control unit 11 enters a standby state (connection standby) while maintaining the communication connection (step S210), and notifies the host device 29 of this standby state (step S211). While in the connection standby state, the control unit 11 updates the data stored in its memory each time it receives vehicle data during communication with the on-board control device 32. The control unit 11 determines whether charging and power supply are possible based on the received vehicle data itself, or calculations performed on it, and temporarily stores this information (step S212). The control unit 11 then notifies the host device 29 of the determined status (step S213).

In step S213, the control unit 11 stores the maximum charging power, maximum discharging power, minimum charging power, minimum discharging power, current charge rate, and whether the vehicle is capable of charging/discharging, based on the vehicle data. These values and conditions may be directly received from the on-board control device 32 and stored in step S209, or they may be derived by calculation from data obtained from the on-board control device 32. Based on this information, the control unit 11 calculates and derives the total capacity (charging capacity) of the energy storage device 30, the amount of energy that can be discharged from a full charge, the amount of energy that can be charged from an empty state, the amount of energy that can be charged from the current charge rate to the upper limit, and the amount of energy that can be discharged from the current charge rate to the lower limit, and stores these as the vehicle ID. In step S213, the control unit 11 notifies the higher-level device 29 of this information.

The control unit 11, in standby mode, determines whether or not a vehicle connection confirmation instruction has been received from the higher-level device 29 (step S214). If it is determined that there is no vehicle connection confirmation instruction (S214: NO), the control unit 11 determines whether or not the stop button has been selected on the operation unit 14 (step S215). If it is determined that the stop button has been selected while the connection remains maintained in standby mode (S215: YES), the control unit 11 stops (terminates) the connection sequence (step S216) and turns off the connector lock (step S217). The control unit 11 disconnects the communication connection (step S218), clears the results of the determination of charging feasibility and power supply feasibility from memory (step S219), and returns the process to step S202, entering a stopped state.

If it is determined that the stop button is not selected (S215: NO), the control unit 11 determines whether or not there is a stop instruction from the higher-level device 29 (step S220). If it is determined that there is a stop instruction (S220: YES), the control unit 11 proceeds to step S218.

If it is determined in step S220 that there is no instruction to stop (S220: NO), the control unit 11 determines whether there is an instruction to charge or discharge from the higher-level device 29 (step S221). If it is determined that there is an instruction to charge or discharge from the higher-level device 29 (S221: YES), the control unit 11 notifies the higher-level device 29 that charging or discharging has started (step S222). The control unit 11 turns ON the DC relay 10a and disconnection relay 10b on the charge/discharge device 1 side and the DC relay 33 on the vehicle V side to start output (step S223), and ends the processing before starting output.

If it is determined that there is neither a charging nor a discharging instruction (S221: NO), the control unit 11 returns to step S214.

If, in step S214, it is determined that there is a vehicle connection confirmation instruction (S214: YES), the control unit 11 notifies the higher-level device 29 of the status stored in step S212 (step S224) without returning to step S204, and then returns the process to step S214.

In step S224, the control unit 11, without having to perform the process of acquiring vehicle data from the on-board control device 32 again, will respond to inquiries with the previously determined charging and power supply status, as long as a connection to the same vehicle V can be confirmed.

As a result of the processing in steps S214 and S224 described above, the charge/discharge device 1 will not execute the connection sequence with the on-board control device 32, even if it receives a vehicle connection confirmation instruction from the higher-level device 29, as long as the vehicle V is not removed from the charge/discharge device 1 and under conditions where no significant change in circumstances is expected. As long as it is certain that the same vehicle V is connected, the charge/discharge device 1 only needs to notify the status it has determined. A case where a change in circumstances is expected is, for example, when a predetermined time has elapsed while the device remains in standby mode.

The higher-level device 29 may query the charge/discharge device 1 every few minutes to confirm the vehicle connection and obtain information about the vehicle V's energy storage device 30. If the connection sequence between the charge/discharge device 1 and the on-board control device 32 is repeated each time, the vehicle V would need to start up from a stopped (standby) state multiple times to respond to the query, thus consuming the 12V battery used for starting. In contrast, the charge/discharge device 1, as long as the vehicle V is not removed, can avoid this battery consumption by notifying the determined status without unnecessarily repeating the connection sequence.

(Third Embodiment)
The configuration of the charge/discharge system 200 in the third embodiment is the same as that of the charge/discharge system 200 in the first embodiment, except for the details of the processing procedure up to the start of charge/discharge which will be described later. Therefore, for the charge/discharge system 200 in the third embodiment that is common with the configuration of the charge/discharge system 200 in the first embodiment, the same reference numerals are used and detailed explanations are omitted.

In the processing procedure described in the third embodiment, compared to the first and second embodiments, the charge/discharge device 1 does not have a "stopped state" and operates in a "standby state" when not performing charge/discharge.

Figures 11 and 12 are flowcharts illustrating an example of the processing procedure in the charge/discharge device 1 of the third embodiment. The control unit 11 of the charge/discharge device 1, in EMS mode which operates by receiving instructions from the higher-level device 29 as described above, executes the following processing procedure.

When the control unit 11 starts up in response to a startup instruction from the host device 29, an instruction from the operation unit 14, or the start of power supply from the power supply unit 13 based on a schedule (step S301), it notifies the host device 29 that it is in a "standby state" before establishing communication with the vehicle V (step S302).

The control unit 11, in standby mode, determines whether a vehicle connection confirmation instruction has been received from the host device 29, or whether a locking operation has been performed on connectors 15 and 35 (step S303). If the control unit 11 determines that there has been no vehicle connection confirmation instruction from the host device 29 and no locking operation has been performed (S303: NO), it determines whether a charging or discharging instruction has been received from the host device 29 (step S304).

If the control unit 11 determines that there is no instruction from the higher-level device 29 to charge or discharge (S304: NO), it returns to step S302 and enters a standby state.

If the control unit 11 determines that there is an instruction from the host device 29 to either charge or discharge (S304: YES), it starts a predetermined connection sequence for the vehicle V to the on-board control device 32 (step S305). The control unit 11 turns on the locks of connectors 15 and 35 (step S306) and notifies the host device 29 that charging or discharging has started (step S307). The control unit 11 turns on the DC relay 10a and disconnection relay 10b on the charge/discharge device 1 side and the DC relay 33 on the vehicle V side to start output (step S308), and ends the pre-output start processing.

If the control unit 11 determines that a vehicle connection confirmation instruction has been received from the host device 29, or that a locking operation has been performed on connectors 15 and 35 (S303: YES), it sends a notification of connection commencement or a response to the instruction to the host device 29 (step S309). The control unit 11 then determines whether the connector lock is ON or OFF (step S310).

If the connector lock is determined to be in the OFF state (S310: NO), the control unit 11 starts a predetermined connection sequence for the vehicle V to the on-board control device 32 (step S311). The control unit 11 then determines whether a communication connection has been established with the on-board control device 32 by starting the predetermined connection sequence (step S312).

If it is determined in step S312 that a communication connection can be established (S312: YES), the control unit 11 turns ON the locks on connectors 15 and 35 (step S313).

The control unit 11 receives vehicle data from the on-board control device 32 and stores it in memory (step S314). The vehicle data includes vehicle identification data (vehicle ID), charging capacity, current charge level (SOC), lower limit charge level, upper limit charge level, charging power, and discharge power. The control unit 11 stops the connection sequence (step S315).

The control unit 11 notifies the host device 29 that it is in standby mode (step S316), disconnects the communication connection, and enters standby mode (disconnection standby) (step S317). Furthermore, based on the vehicle data received in step S314, it determines whether charging and power supply are possible and temporarily stores this information (step S318). The control unit 11 then notifies the host device 29 of the determined status (step S319).

If it is determined in step S310 that the connector lock is already ON (S310: YES), the control unit 11 notifies the host device 29 of the status stored in step S318 (step S320), since notification has already been given, and returns the process to step S302. If it is determined in step S312 that communication connection cannot be established (S312: NO), the control unit 11 interrupts the connection sequence and returns the process to step S302.

In the third embodiment as well, the connection sequence is not repeated while the connector lock is ON, thereby reducing the number of system startups in the vehicle V.

(Variant)
Figures 13 and 14 are flowcharts showing an example of the processing procedure in a modified charge/discharge device 1 of the third embodiment. The control unit 11 of the charge/discharge device 1 operates in EMS mode, which receives instructions from the host device 29 as described above, and executes the following processing procedure.

In Modification 3, the charge/discharge device 1 does not perform the ON/OFF locking process for connectors 15 and 35. Therefore, when the control unit 11 determines that there is an instruction from the host device 29 to either charge or discharge (S304: YES), it starts a predetermined connection sequence (S305), notifies the host device 29 that charging or discharging has started without turning on the connector lock (S307), and then starts charging or discharging (S308).

Then, in step S303, if the charge/discharge device 1 determines that a vehicle connection confirmation instruction has been received from the host device 29, or that the lock operation of connectors 15 and 35 has been performed (S303: YES), the control unit 11 sends a notification of connection commencement or a response to the instruction to the host device 29 (S309), and then determines whether the connection frequency with the vehicle V is equal to or greater than a predetermined frequency (predetermined number of times) (step S321). If it is determined that the connection frequency is equal to or greater than the predetermined frequency (S321: YES), the control unit 11 notifies the host device 29 of the status stored in step S318 (S320), and the process returns to step S302.

If it is determined that the connection frequency is not above a predetermined frequency (S321: NO), the control unit 11 starts the connection sequence (S311). If a communication connection is established (S312: YES), it receives and stores vehicle data without turning on the connector lock (S314). The control unit 11 then executes the processing from step S315 onward.

Regardless of whether the connector is locked or not, if it is determined that a connection to the same vehicle V is maintained, the system performs a connection sequence (communication connection) once and notifies the host device 29 of the charging and discharging status determined from the received vehicle data. This reduces the number of times the system needs to be started unnecessarily in vehicle V.

(Fourth Embodiment)
Figure 15 is a block diagram showing the configuration of the charge/discharge device 1 of the fourth embodiment. Figure 15 also includes the connection configuration with the vehicle V, similar to Figure 2 in the first embodiment. Of the components of the charge/discharge device 1 shown in Figure 15, components common to the charge/discharge device 1 of the first embodiment are denoted by the same reference numerals and detailed explanations are omitted.

In the fourth embodiment, the charge/discharge device 1 includes an acquisition unit 17 for acquiring data from an external source. The acquisition unit 17 may be a terminal for receiving external signals, or it may be a communication interface such as a serial communication interface. The control unit 11 can acquire data from an external source via the acquisition unit 17. The acquisition unit 17 may, for example, receive an image signal or an ON/OFF switch signal. In Figure 15, a camera 5 is connected to the acquisition unit 17, and the acquisition unit 17 can acquire image data via an image signal. The acquisition unit 17 outputs the acquired image data to the control unit 11.

Camera 5 is installed to capture images of the vehicle V connected to the charging/discharging device 1. The control unit 11 can determine whether the vehicle V connected to the charging/discharging device 1 has changed, that is, whether the same vehicle V remains connected, by performing image recognition processing on the image data acquired from the acquisition unit 17.

Camera 5 can be replaced with other sensors capable of recognizing vehicle V. The control unit 11 may acquire identification data from vehicle V and determine whether vehicle V remains present at that location. Camera 5 can also be replaced with a user authentication device for vehicle V. If the user is the same, it can be recognized that the same vehicle is connected.

Figures 16 and 17 are flowcharts illustrating an example of the processing procedure in the charge/discharge device 1 of the fourth embodiment. For the processing procedures shown in the flowcharts of Figures 16 and 17, steps that are common to the flowcharts of Figures 3 and 4 of the first embodiment are given the same step numbers, and detailed explanations are omitted.

The control unit 11 is activated (S101), notifies the host device 29 that it is in a stopped state before establishing communication with the vehicle V (S102), and identifies the vehicle V based on the image data of the vehicle to be connected (step S401).

In the fourth embodiment, when the control unit 11 determines that a vehicle connection confirmation instruction has been received (S115: YES), it determines whether or not it is the same vehicle based on the image data acquired from the camera 5 (step S402). If it determines that it is the same vehicle (S402: YES), it notifies the host device 29 of the status stored in step S113 (step S124), and returns the process to step S115.

If, based on the image data acquired from camera 5, it is determined that the vehicle is not the same (S402: NO), then the control unit 11 returns to step S104 and performs a reconnection process, as it is necessary to acquire vehicle data again. At this time, the control unit 11 may also output an error to the operation unit 14.

The embodiments disclosed above are illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, and all modifications within the meaning and scope equivalent to the claims are included.

1 Charge/discharge device 11 Control unit 10 Charge/discharge circuit 10a DC relay 10b Disconnect relay 1P Computer program V Vehicle 30 Energy storage device 32 On-board control device 33 DC relay

Claims (7)

A control method for a charge/discharge device connected to an on-board battery that serves as a DC power source in a vehicle, which controls charging and discharging between the on-board battery and a power source or load,
The charging and discharging device comprises a vehicle communication unit that communicates with an on-board control device that controls the charging and discharging of the on-board battery on the vehicle side, and a higher-level communication unit that communicates with a higher-level device.
The charging and discharging device is
The vehicle communication unit acquires data related to the on-board battery from the on-board control device.
After storing the aforementioned data, if a data acquisition instruction for the on-board battery is received from the higher-level device before charging or discharging begins, the vehicle will respond to the data acquisition instruction based on the stored data while the vehicle is connected to the charging/discharging device .
If a command to stop charging/discharging is issued before charging/discharging begins, the stored data will be erased.
If the data acquisition instruction is received again, the vehicle will acquire data from the on-board control device via the vehicle communication unit and respond to the data acquisition instruction.
Charge/discharge control method. A control method for a charge/discharge device connected to an on-board battery that serves as a DC power source in a vehicle, which controls charging and discharging between the on-board battery and a power source or load,
The charging and discharging device comprises a vehicle communication unit that communicates with an on-board control device that controls the charging and discharging of the on-board battery on the vehicle side, and a higher-level communication unit that communicates with a higher-level device.
The charging and discharging device is
The vehicle communication unit acquires data related to the on-board battery from the on-board control device.
After storing the aforementioned data, if a data acquisition instruction for the on-board battery is received from the higher-level device before charging or discharging begins, the device will respond to the data acquisition instruction based on the stored data while the vehicle is connected to the charging/discharging device.
If the lock on the connector connected to the vehicle is turned OFF before charging or discharging begins, the stored data will be erased.
If the data acquisition instruction is received again, the vehicle will acquire data from the on-board control device via the vehicle communication unit and respond to the data acquisition instruction.
Charge/discharge control method. A control method for a charge/discharge device connected to an on-board battery that serves as a DC power source in a vehicle, which controls charging and discharging between the on-board battery and a power source or load,
The charging and discharging device comprises a vehicle communication unit that communicates with an on-board control device that controls the charging and discharging of the on-board battery on the vehicle side, and a higher-level communication unit that communicates with a higher-level device.
The charging and discharging device is
The vehicle communication unit acquires data related to the on-board battery from the on-board control device.
After storing the aforementioned data, if a data acquisition instruction for the on-board battery is received from the higher-level device before charging or discharging begins, the device will respond to the data acquisition instruction based on the stored data while the vehicle is connected to the charging/discharging device.
If the stop operation is performed before charging or discharging begins, the stored data will be erased.
If the data acquisition instruction is received again, the vehicle will acquire data from the on-board control device via the vehicle communication unit and respond to the data acquisition instruction.
Charge/discharge control method. A control method for a charge/discharge device connected to an on-board battery that serves as a DC power source in a vehicle, which controls charging and discharging between the on-board battery and a power source or load,
The charging and discharging device comprises a vehicle communication unit that communicates with an on-board control device that controls the charging and discharging of the on-board battery on the vehicle side, and a higher-level communication unit that communicates with a higher-level device.
The charging and discharging device is
The vehicle communication unit acquires data related to the on-board battery from the on-board control device.
After storing the aforementioned data, if a data acquisition instruction for the on-board battery is received from the higher-level device before charging or discharging begins, the vehicle will respond to the data acquisition instruction based on the stored data while the vehicle is connected to the charging/discharging device.
While the lock on the connector connected to the vehicle is ON before charging and discharging begins, the system responds to the data acquisition instruction based on the stored data.
Charge/discharge control method. A control method for a charge/discharge device connected to an on-board battery that serves as a DC power source in a vehicle, which controls charging and discharging between the on-board battery and a power source or load,
The charging and discharging device comprises a vehicle communication unit that communicates with an on-board control device that controls the charging and discharging of the on-board battery on the vehicle side, and a higher-level communication unit that communicates with a higher-level device.
The charging and discharging device is
The vehicle communication unit acquires data related to the on-board battery from the on-board control device.
After storing the aforementioned data, if a data acquisition instruction for the on-board battery is received from the higher-level device before charging or discharging begins, the vehicle will respond to the data acquisition instruction based on the stored data while the vehicle is connected to the charging/discharging device.
If the frequency of receiving the data acquisition instruction exceeds a predetermined frequency, the system will respond to the data acquisition instruction based on the stored data without initiating a connection with the in-vehicle control device.
Charge/discharge control method. A control method for a charge/discharge device connected to an on-board battery that serves as a DC power source in a vehicle, which controls charging and discharging between the on-board battery and a power source or load,
The charging and discharging device comprises a vehicle communication unit that communicates with an on-board control device that controls the charging and discharging of the on-board battery on the vehicle side, and a higher-level communication unit that communicates with a higher-level device.
The charging and discharging device is
The vehicle communication unit acquires data related to the on-board battery from the on-board control device.
After storing the aforementioned data, if a data acquisition instruction for the on-board battery is received from the higher-level device before charging or discharging begins, the device will respond to the data acquisition instruction based on the stored data while the vehicle is connected to the charging/discharging device.
Determine if the same vehicle is connected,
If it is determined that a connection is established, the system will respond to the data acquisition instruction based on the stored data without initiating a connection with the in-vehicle control device.
Charge/discharge control method. A charge/discharge device connected to an on-board battery installed in a vehicle, which controls charging and discharging between the on-board battery and a power source or load, comprising a control unit that performs the charge/discharge control method described in any one of claims 1 to 6.
Charge/discharge device.