JP2020018120A - Charge / discharge device and charge / discharge system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a charging/discharging device and a charging/discharging system capable of reducing the number of times a stop signal is received from an electric vehicle without excessively narrowing the SOC band of an on-vehicle battery. A charging/discharging device (20) includes a power conversion unit (21) that performs a charging/discharging operation on a vehicle-mounted battery (61) of an electric vehicle (60), and a control unit (22) that controls the power conversion unit. , The communication unit that receives the stop signal from the electric vehicle 60 and performs the disconnection operation and the reconnection operation, and the “charging limit value” of the vehicle-mounted battery 61 to a value smaller than the SOC of the vehicle-mounted battery 61 after the stop detection. On the other hand, the limit value setting unit that sets the “discharge limit value” of the vehicle-mounted battery 61 to a value larger than the SOC of the vehicle-mounted battery 61 after the stop detection, and the SOC of the vehicle-mounted battery 61 is “charge limit value” or “charge limit value”. And a charge and discharge control unit that stops the charge and discharge operation when the discharge limit value is reached. [Selection diagram] Figure 1

Description

  The present invention relates to a charging / discharging device and a charging / discharging system for charging / discharging a vehicle-mounted battery.

  BACKGROUND ART As a charge / discharge device for charging / discharging an in-vehicle battery, for example, one described in Patent Document 1 is known. The charge / discharge device described in Patent Literature 1 uses a power generated by a solar power generation device and commercial power supplied from a grid to charge a vehicle-mounted battery of an electric vehicle such as an electric vehicle. In this charging / discharging device, the user can select a mode of charging the vehicle-mounted battery using only the generated power or a mode of charging the vehicle-mounted battery using both the generated power and the commercial power.

JP 2015-228714 A

  As shown in FIG. 6, when the SOC of the on-vehicle battery reaches a predetermined upper limit (for example, SOC 80%) or a predetermined lower limit (for example, SOC 30%), a general electric vehicle issues a stop signal regarding a normal stop. In addition to transmitting to the charging / discharging device, the contactor is opened based on the instruction from the charging / discharging device, and the connection between the vehicle-mounted battery and the charging / discharging device is released.

  A conventional charge / discharge device that charges on-vehicle batteries by using the power generated by a solar power generation device may repeat charging completion (stop) and discharge operation when the SOC of on-vehicle batteries is close to an upper limit value, for example. is there. In this case, the contactor is opened and closed many times on the electric vehicle side, so that the life of the contactor is shortened.

  Further, each time the charging / discharging device receives the stop signal from the electric vehicle, the charging / discharging device temporarily disconnects from and reconnects with the electric vehicle. The charge / discharge device performs predetermined processing such as insulation diagnosis with the electric vehicle when reconnecting. For this reason, it takes time to restart charging / discharging, and during this time, there is a problem that the power generated by the photovoltaic power generator cannot be used effectively.

  Note that the charging / discharging operation may be stopped from the charging / discharging device side immediately before the upper limit value and the lower limit value so that the SOC of the vehicle-mounted battery does not reach the upper limit value and the lower limit value. However, the upper limit value and the lower limit value differ depending on the vehicle type and the manufacturer, and when the specific numerical value is not notified to the charging / discharging device side, or even when notified, the charging / discharging operation is stopped at a numerical value different from the notified numerical value. Sometimes.

  For this reason, it is difficult for the charging / discharging device to stop the charging / discharging operation immediately before estimating the upper limit value and the lower limit value. For example, if the charging / discharging operation is stopped with a margin, it is possible to cope with many vehicles (utilize surplus power from sunlight), but the SOC band of a vehicle battery that can be used is narrowed.

  The present invention has been made in view of the above circumstances, and it is an object of the present invention to reduce the number of times a stop signal is received from an electric vehicle without excessively narrowing the SOC band of a vehicle-mounted battery. A discharge device and a charge / discharge system are provided.

In order to solve the above-described problems, a charge and discharge device according to the present invention includes:
A power conversion unit that performs a charge / discharge operation on a vehicle-mounted battery of the electric vehicle;
A control unit that controls the power conversion unit;
A charge / discharge device comprising:
The control unit includes:
A detection unit that detects a stop of the charging / discharging operation for the on-vehicle battery and disconnects the connection with the electric vehicle and performs a reconnection operation to restart the connection with the electric vehicle after the disconnection operation. ,
The charging limit value of the vehicle-mounted battery is set to a value smaller than the SOC of the vehicle-mounted battery after the stop detection, while the discharge limit value of the vehicle-mounted battery is set to be larger than the SOC of the vehicle-mounted battery after the stop detection. A limit value setting section for setting a value,
A charge / discharge control unit that stops the charge / discharge operation when the SOC of the vehicle-mounted battery reaches the charge limit value or the discharge limit value.

  In this configuration, the limit value setting unit sets the charge limit value to a value smaller than the SOC of the vehicle-mounted battery after detecting the stop of the charging operation for the vehicle-mounted battery, while setting the discharge limit value to the SOC of the vehicle-mounted battery after the stop detection. The charge / discharge control unit stops the charge / discharge operation when the SOC of the vehicle-mounted battery reaches the charge limit value or the discharge limit value. Therefore, according to this configuration, the number of receptions of the stop signal from the electric vehicle can be reduced without excessively narrowing the SOC band of the vehicle-mounted battery.

In the above charging / discharging device,
The limit value setting unit,
When the SOC of the vehicle-mounted battery is equal to or greater than a first threshold and the first condition that the operation of the power conversion unit at the time of the stop detection is a charging operation is satisfied, the SOC of the vehicle-mounted battery after the stop is detected Is stored as a charging upper limit value, while the charging limit value is set to a value smaller than the charging upper limit value,
When the SOC of the vehicle-mounted battery is equal to or less than a second threshold value and the second condition that the operation of the power conversion unit at the time of the stop detection is a discharging operation is satisfied, the SOC of the vehicle-mounted battery after the stop detection is satisfied. Is stored as the lower discharge limit, and the discharge limit value is set to a value larger than the lower discharge limit.

In the above charging / discharging device,
The limit value setting unit may store the charge upper limit value or the discharge lower limit value after the reconnection operation.

In the above charging / discharging device,
The limit value setting unit may store the charge upper limit value or the discharge lower limit value before the disconnection operation.

Further, in order to solve the above problems, the charge and discharge system according to the present invention,
A power conditioner device, and a charge / discharge system including any of the above charge / discharge devices,
The power conditioner device,
A first converter unit connected to the solar power generation device and the charge / discharge device, and configured to supply the generated power of the solar power generation device to the charge / discharge device;
An inverter unit that is connected to the first converter unit and the load, converts DC power output from the first converter unit into AC power, and supplies the AC power to the load;
A power conditioner control unit that controls the first converter unit and the inverter unit.

The charging / discharging system further includes a storage battery,
The power conditioner device,
An operation of being connected to the storage battery, the first converter unit and the inverter unit, and charging the storage battery using the DC power output from the first converter unit under the control of the power conditioner control unit; And a second converter unit for performing an operation of supplying discharge power of the storage battery to the inverter unit.

  According to the present invention, it is possible to provide a charge / discharge device and a charge / discharge system capable of reducing the number of times a stop signal is received from an electric vehicle without excessively narrowing an SOC band of a vehicle-mounted battery.

1 is a block diagram of a charge / discharge device and a charge / discharge system according to the present invention. It is a block diagram of a control part of the charge and discharge device concerning the present invention. 5 is a flowchart of charge / discharge control according to the present invention. 5 is a graph showing a change in the SOC of the vehicle-mounted battery during charge / discharge control according to the present invention. It is a flow chart of charge and discharge control concerning a modification of the present invention. 7 is a graph showing a change in SOC of a vehicle-mounted battery during conventional charge / discharge control.

  Hereinafter, embodiments of a charge / discharge device and a charge / discharge system according to the present invention will be described with reference to the accompanying drawings.

  FIG. 1 shows a charge / discharge system 1 according to an embodiment of the present invention. The charge / discharge system 1 includes a power conditioner device 10, a charge / discharge device 20 according to an embodiment of the present invention, and a storage battery 30.

  The power conditioner device 10 includes a first converter unit 11, a second converter unit 12, an inverter unit 13, and a power conditioner control unit 14. The power conditioner device 10 is connected to a storage battery 30, a solar power generation device 40, a load (home load) 50, and a system.

  The first converter unit 11 is, for example, a DC / DC converter configured by a boost chopper circuit. The first converter unit 11 outputs DC power obtained by boosting the power generated by the solar power generation device 40. The first converter unit 11 performs an MPPT operation (maximum power point tracking operation) on the power generated by the photovoltaic power generation device 40 under the control of the power conditioner control unit 14.

  The second converter unit 12 is, for example, a bidirectional DC / DC converter configured by a bidirectional chopper circuit. The second converter unit 12 charges and discharges the storage battery 30 under the control of the power conditioner control unit 14.

  The inverter unit 13 is, for example, a bidirectional AC / DC converter. The inverter unit 13 has an AC terminal side connected to the load 50 and a system (not shown), and a DC terminal side connected to the first converter unit 11 and the second converter unit 12. The inverter unit 13 converts the system power into DC and supplies the DC power to the second converter unit 12 or converts the DC power input to the DC terminal into AC and supplies the AC to the load 50 or the system.

  The power conditioner control unit 14 includes a microcomputer and / or a dedicated IC. The power conditioner control unit 14 controls the first converter unit 11, the second converter unit 12, and the inverter unit 13 while switching a plurality of operation modes.

  The power conditioner device 10 includes an economic mode and a green mode as operation modes. The economic mode is a mode in which the surplus of the generated power of the photovoltaic power generation device 40 is output to the grid side to sell the power, and the economy is emphasized. On the other hand, in the green mode, the surplus of the power generated by the photovoltaic power generation device 40 is used for charging an electric vehicle 60 such as an electric vehicle or a plug-in hybrid vehicle connected to the charging / discharging device 20 or charging the storage battery 30. This mode is used for In the present embodiment, the charging of the electric vehicle 60 is prioritized, and the storage battery 30 is charged only when the electric vehicle 60 is not charged.

  When the operation mode is the green mode and the generated power of the solar power generation device 40 is larger than the power consumption of the load 50, the surplus generated power is supplied to the electric vehicle 60 with priority. For example, when the generated power is 4 kW and the power consumption of the load 50 is 3 kW, the surplus 1 kW is supplied to the electric vehicle 60. On the other hand, when the operation mode is the green mode and the generated power of the solar power generation device 40 is smaller than the power consumption of the load 50, the shortage of the generated power is supplemented by the electric vehicle 60. For example, when the generated power is 2 kW and the power consumption of the load 50 is 3 kW, the shortage of 1 kW is supplied from the electric vehicle 60.

  As described above, when the operation mode is the green mode, the charging operation and the discharging operation of the electric vehicle 60 are frequently switched depending on the state of the power generated by the solar power generation device 40 and the power consumption of the load 50.

  The charging / discharging device 20 according to an embodiment of the present invention is, for example, a V2H (Vehicle to Home) stand, and includes a power conversion unit 21 and a control unit 22. The charging / discharging device 20 is connected to the electric vehicle 60 by a charging cable.

  The power conversion unit 21 includes, for example, a bidirectional DC / DC converter, and performs a charging / discharging operation (charging operation and discharging operation) with respect to the vehicle-mounted battery 61 of the electric vehicle 60. A contactor 62 is interposed in a power line connecting the charging cable and the vehicle-mounted battery 61.

  The control unit 22 includes a microcomputer and / or a dedicated IC, and performs mutual communication (for example, CAN communication) with the power conditioner control unit 14 and the vehicle control unit 63 of the electric vehicle 60.

  As illustrated in FIG. 2, the control unit 22 includes a communication unit 23, a charge / discharge control unit 24, and a limit value setting unit 25. Limit value setting section 25 includes storage section 26.

  The communication unit 23 communicates with the power conditioner control unit 14 and the vehicle control unit 63 mutually. The information (for example, the SOC of the vehicle-mounted battery 61 and various command signals) received by the communication unit 23 can be shared by the charge / discharge control unit 24 and the limit value setting unit 25. The communication unit 23 receives a stop signal related to a normal stop from the vehicle control unit 63 to release the connection with the electric vehicle 60, and restarts the connection with the electric vehicle 60 after the disconnection operation. Connection operation ". Thus, in the present embodiment, the communication unit 23 functions as the “detection unit” of the present invention.

  The disconnection operation includes an operation of opening the contactor 62 through an opening command from the vehicle control unit 63 (an operation of sending an opening command of the contactor 62 to the vehicle control unit 63) and an operation of disconnecting communication with the vehicle control unit 63. And are included. The reconnection operation includes an operation of restarting communication with the vehicle control unit 63 and an operation of closing the contactor 62 through a close command by the vehicle control unit 63 (operation of sending a close command of the contactor 62 to the vehicle control unit 63). Is included.

  The charge / discharge control unit 24 controls the charge / discharge operation of the power conversion unit 21. When receiving the stop signal from the vehicle control unit 63, the charge / discharge control unit 24 stops the charge / discharge operation, and restarts the charge / discharge operation after the reconnection operation of the communication unit 23.

  When the SOC of the vehicle-mounted battery 61 reaches the following “charge limit value”, the charge / discharge control unit 24 stops the charging operation of the power conversion unit 21 and the SOC of the vehicle-mounted battery 61 becomes the following “discharge limit value”. When it reaches, the discharging operation of the power conversion unit 21 is stopped.

  The limit value setting unit 25 causes the storage unit 26 to store the SOC of the vehicle-mounted battery 61 after receiving the stop signal, as a “charge upper limit value” or a “discharge lower limit value”. Specifically, when the SOC of the vehicle-mounted battery 61 is equal to or greater than the first threshold value (70% in the present embodiment) and the operation of the power conversion unit 21 at the time of receiving the stop signal is a charging operation, the limit value setting unit 25 Then, the SOC of the vehicle-mounted battery 61 is stored in the storage unit 26 as the “charge upper limit value”. On the other hand, when the SOC of the vehicle-mounted battery is equal to or less than the second threshold value (30% in the present embodiment) and the operation of the power conversion unit 21 at the time of receiving the stop signal is a discharging operation, the limit value setting unit 25 sets The SOC of 61 is stored in the storage unit 26 as the “discharge lower limit value”.

  Then, the limit value setting unit 25 sets the “charge limit value” to a value smaller than the charge upper limit value, and sets the “discharge limit value” to a value larger than the discharge lower limit value. In the present embodiment, the charge limit value is set to a value of a charge upper limit value −5%, and the discharge limit value is set to a value of a discharge lower limit value + 5%. The set “charge limit value” and “discharge limit value” are stored in the storage unit 26.

  Referring to FIG. 1 again, vehicle control unit 63 of electric vehicle 60 stops when the SOC of vehicle-mounted battery 61 reaches a predetermined upper limit (for example, SOC 80%) or a predetermined lower limit (for example, SOC 30%). The signal is transmitted to the control unit 22 of the charging / discharging device 20.

  When receiving the stop signal, the control unit 22 of the charge / discharge device 20 stops the charge / discharge operation and instructs the vehicle control unit 63 to open the contactor 62. The vehicle control unit 63 that has received the release command from the control unit 22 opens the contactor 62 to electrically cut off the vehicle-mounted battery 61 from the charge / discharge device 20. Here, if the contactor 62 is opened and closed many times a day, the life of the contactor 62 is shortened.

  In the present embodiment, after the charge / discharge limit value is set, the SOC of the vehicle-mounted battery 61 does not reach the upper limit value or the lower limit value. Therefore, the number of times the vehicle control unit 63 transmits the stop signal (for example, when the contactor 62 is opened or Closing times).

  Next, a method of controlling charging and discharging of the vehicle-mounted battery 61 performed by the control unit 22 will be described with reference to FIG. Here, it is assumed that the operation mode of the power conditioner device 10 is the green mode, and the time period in which the surplus power generated by the solar power generation device 40 can be used for charging the vehicle-mounted battery 61 is used.

  When the charge / discharge operation is started, the control unit 22 controls the power conversion unit 21 to perform the charge / discharge operation in the charge / discharge limit value band (S1). In the present embodiment, the default value of the “charge limit value” is SOC 100%, the default value of the “discharge limit value” is SOC 10%, and these values are stored in the storage unit 26.

  The control unit 22 then determines whether or not a stop signal has been received from the vehicle control unit 63 (S2), and if a stop signal has been received (YES in S2), stops the charge / discharge operation of the power conversion unit 21. Then, a disconnection operation is performed (S3). The control unit 22 performs an operation of sending a command to open the contactor 62 and an operation of disconnecting communication with the vehicle control unit 63 as a disconnection operation.

  Next, the control unit 22 determines whether the first condition regarding the upper charging limit is satisfied (S4). The first condition is a condition that the SOC of the vehicle-mounted battery 61 immediately before the disconnection operation is equal to or more than a first threshold value (70% in the present embodiment) and that the operation of the power conversion unit 21 at the time of receiving the stop signal is a charging operation. is there. By this determination, the control unit 22 can infer that the vehicle-mounted battery 61 is in a fully charged (or nearly fully charged) state.

  When determining that the first condition is satisfied (YES in S4), the control unit 22 performs a reconnection operation (S5). Specifically, the control unit 22 performs an operation of performing a predetermined process such as insulation diagnosis with the electric vehicle 60, an operation of restarting communication with the vehicle control unit 63, and an operation of sending a command to close the contactor 62. Do.

  The control unit 22 that has resumed the communication with the vehicle control unit 63 receives the information on the SOC of the vehicle-mounted battery 61 from the vehicle control unit 63, and stores the SOC in the storage unit 26 as the “charge upper limit value” (S6). Thereby, control unit 22 can store the value of the SOC of vehicle-mounted battery 61 when the stop signal is transmitted from vehicle control unit 63, in other words, the upper limit value of the SOC set by vehicle control unit 63. .

  Next, the control unit 22 sets the “charge limit value” to a value smaller than the “charge upper limit value” (in this embodiment, the charge upper limit value—5%) (S7). The set “charge limit value” is stored in the storage unit 26. When the "charge upper limit" is SOC 80%, the "charge limit" is SOC 75%, and when the "discharge limit" is not updated from the default value, the band of the charge / discharge limit is SOC 10% to 75%. Becomes

  The control unit 22 having set the charging limit value waits until the discharging operation is started. If the charging operation is performed after the discharging operation is started (return to “start of charging / discharging operation”), the operation is performed at the charging limit value or less (S1), and the operation waits when the SOC reaches 75%. Since the “charge upper limit” is 80% SOC, the control unit 22 stops the charging operation of the power conversion unit 21 before the SOC of the vehicle-mounted battery 61 reaches the “charge upper limit”, that is, before the stop signal is transmitted. Can be done. If the charging operation is to be performed immediately after the start of the discharging operation (when the SOC exceeds 75%), the standby state is set without performing the charging operation.

  Also, the control unit 22 controls the charging of the power conversion unit 21 when the standby signal regarding the standby command is received from the power conditioner control unit 14 before the “charge limit value” is updated from SOC 80% to 75%. The discharging operation is stopped and a standby state is set. Furthermore, the control unit 22 also enters the standby state when the power generation of the photovoltaic power generation device 40> the power consumption of the load 50 and the SOC of the vehicle-mounted battery 61 has reached the “charge limit value”.

  On the other hand, if it is determined in step S4 that the first condition is not satisfied (NO in S4), it is determined whether the second condition regarding the lower discharge limit is satisfied (S8). The second condition is a condition that the SOC of the vehicle-mounted battery immediately before the disconnection operation is equal to or less than the second threshold value (30% in the present embodiment) and that the operation of the power conversion unit 21 at the time of receiving the stop signal is a discharging operation. is there. Thereby, the control unit 22 can infer that the in-vehicle battery 61 is empty (or nearly empty).

  When determining that the second condition is satisfied (YES in S8), the control unit 22 performs a reconnection operation (S9). The control unit 22 that has restarted communication with the vehicle control unit 63 by the reconnection operation receives the information on the SOC of the vehicle-mounted battery 61 from the vehicle control unit 63 and stores the SOC in the storage unit 26 as the “discharge lower limit value”. (S10). Thereby, control unit 22 can store the value of the SOC of vehicle-mounted battery 61 when the stop signal is transmitted from vehicle control unit 63, in other words, the lower limit value of the SOC set by vehicle control unit 63. .

  Next, the control unit 22 sets the “discharge limit value” to a value larger than the “discharge lower limit value” (in this embodiment, the discharge lower limit value + 5%) (S11). The set “discharge limit value” is stored in the storage unit 26. When the “discharge lower limit value” is SOC 30%, the “discharge limit value” is SOC 35%, and when the “charge limit value” is updated to SOC 75%, the band of the charge / discharge limit value is SOC 35% to 75%. Becomes

  The control unit 22 having set the discharge limit value waits until the charging operation is started. If the discharging operation is performed after the charging operation is started (return to “start of charging / discharging operation”), the operation is performed at the discharge limit value or less (S1), and the operation waits when the SOC reaches 35%. Since the “discharge lower limit” is 30% SOC, the control unit 22 stops the discharging operation of the power conversion unit 21 before the SOC of the vehicle-mounted battery 61 reaches the “discharge lower limit”, and the SOC of the vehicle-mounted battery 61 becomes “charged”. Before reaching the “upper limit”, the charging operation of the power conversion unit 21 can be stopped. When the discharging operation is to be performed immediately after the charging operation is started (when the SOC is less than 35%), the standby state is performed without performing the discharging operation.

  The control unit 22 also controls the charging of the power conversion unit 21 when the standby signal regarding the standby command is received from the power conditioner control unit 14 before the “discharge limit value” is updated from SOC 30% to 35%. The discharging operation is stopped and a standby state is set. Further, the control unit 22 also enters the standby state when the power generation of the solar power generation device 40 <the power consumption of the load 50 and the SOC of the vehicle-mounted battery 61 has reached the “discharge limit value”.

  By the way, the vehicle control unit 63 transmits a stop signal to the control unit 22 even when the SOC of the on-vehicle battery 61 does not reach the upper limit value or the lower limit value when charging and discharging of several hundred W or less continue for a predetermined time. There is. In this case, the control unit 22 determines that the first condition is not satisfied in the determination of Step S4 (NO in S4), and determines that the second condition is not satisfied in the determination of Step S8 (NO in S8). ). Then, the control unit 22 shifts to the standby state without performing the reconnection operation, storing the charge upper limit value and the discharge lower limit value, and storing the charge / discharge limit value (S12).

  Next, with reference to FIG. 4, a change in the SOC of the vehicle-mounted battery 61 during the charge / discharge control of the control unit 22 will be described. Also in this case, the operation mode of the power conditioner device 10 is the green mode.

  In the time zone (a), the control unit 22 receives the standby signal from the power conditioner control unit 14 and is in the standby state, so that the SOC of the vehicle-mounted battery 61 does not change and remains at a constant value.

  In the time zone (b), the generated power of the photovoltaic power generator 40 <the power consumption of the load 50, and the control unit 22 causes the power conversion unit 21 to perform a discharging operation to discharge the vehicle-mounted battery 61. Therefore, the SOC of the vehicle-mounted battery 61 decreases.

  In the time zone (c), the generated power of the photovoltaic power generation device 40> the power consumption of the load 50, and the control unit 22 causes the power conversion unit 21 to perform a charging operation, and uses the surplus of the generated power to mount the vehicle-mounted battery. 61 is charged. Therefore, the SOC of the vehicle-mounted battery 61 increases. When the SOC of the vehicle-mounted battery 61 reaches a predetermined upper limit, a stop signal is transmitted from the vehicle control unit 63 to the control unit 22.

  In the time zone (d), the generated power of the photovoltaic power generator 40> the power consumption of the load 50, and the control unit 22 is in a standby state after receiving a standby signal from the power conditioner control unit 14. For this reason, the SOC of the vehicle-mounted battery 61 remains unchanged at a constant value. The control unit 22 stores the “charge upper limit value” in this time zone and sets the “charge limit value”.

  In the time zone (e), the generated power of the photovoltaic power generation device 40 <the power consumption of the load 50, and the control unit 22 causes the power conversion unit 21 to perform a discharging operation to discharge the vehicle-mounted battery 61. Therefore, the SOC of the vehicle-mounted battery 61 decreases.

  In the time zone (f), the generated power of the photovoltaic power generation device 40> the power consumption of the load 50, and the control unit 22 causes the power conversion unit 21 to perform a charging operation, and uses the surplus of the generated power to mount the on-vehicle battery. 61 is charged. Therefore, the SOC of the vehicle-mounted battery 61 increases. When the SOC of the vehicle-mounted battery 61 reaches the “charge limit value”, the control unit 22 stops the charging operation of the power conversion unit 21. In this case, the stop signal is not transmitted from the vehicle control unit 63 to the control unit 22, and the contactor 62 remains closed.

  In the time zone (g), the generated power of the photovoltaic power generation device 40> the power consumption of the load 50, and the SOC of the vehicle-mounted battery 61 has reached the “charge limit value”. For this reason, the control unit 22 is in a standby state, and the SOC of the vehicle-mounted battery 61 remains unchanged at a constant value.

  In the time period (h), the generated power of the photovoltaic power generation device 40 <the power consumption of the load 50, and the control unit 22 causes the power conversion unit 21 to perform a discharging operation to discharge the vehicle-mounted battery 61. Therefore, the SOC of the vehicle-mounted battery 61 decreases. When the SOC of the vehicle-mounted battery 61 reaches a predetermined lower limit, a stop signal is transmitted from the vehicle control unit 63 to the control unit 22.

  In the time zone (i), the generated power of the photovoltaic power generation device 40 <the power consumption of the load 50, and the control unit 22 receives a standby signal from the power conditioner control unit 14 and is in a standby state. For this reason, the SOC of the vehicle-mounted battery 61 remains unchanged at a constant value. The control unit 22 stores the “discharge lower limit value” in this time zone and sets the “discharge limit value”.

  In the time zone (j), the generated power of the photovoltaic power generation device 40> the power consumption of the load 50, and the control unit 22 causes the power conversion unit 21 to perform a charging operation, and uses the surplus of the generated power to mount the on-vehicle battery. 61 is charged. Therefore, the SOC of the vehicle-mounted battery 61 increases.

  In the time zone (k), the generated power of the photovoltaic power generation device 40 <the power consumption of the load 50, and the control unit 22 causes the power conversion unit 21 to perform a discharging operation to discharge the vehicle-mounted battery 61. Therefore, the SOC of the vehicle-mounted battery 61 decreases. When the SOC of the vehicle-mounted battery 61 reaches the “discharge limit value”, the control unit 22 stops the discharging operation of the power conversion unit 21. In this case, the stop signal is not transmitted from the vehicle control unit 63 to the control unit 22, and the contactor 62 remains closed.

  In the time zone (l), the generated power of the photovoltaic power generation device 40 <the power consumption of the load 50, and the SOC of the vehicle-mounted battery 61 has reached the “discharge limit value”. For this reason, the control unit 22 is in a standby state, and the SOC of the vehicle-mounted battery 61 remains unchanged at a constant value.

  In the time zone (m), the generated power of the photovoltaic power generation device 40> the power consumption of the load 50, and the control unit 22 causes the power conversion unit 21 to perform a charging operation, and uses the surplus of the generated power to mount the vehicle-mounted battery. 61 is charged. Therefore, the SOC of the vehicle-mounted battery 61 increases. When the SOC of the vehicle-mounted battery 61 reaches the “charge limit value”, the control unit 22 stops the charging operation of the power conversion unit 21. In this case, the stop signal is not transmitted from the vehicle control unit 63 to the control unit 22, and the contactor 62 remains closed.

  In the time zone (n), the generated power of the photovoltaic power generation device 40> the power consumption of the load 50, and the SOC of the vehicle-mounted battery 61 has reached the “charge limit value”. For this reason, the control unit 22 is in a standby state, and the SOC of the vehicle-mounted battery 61 remains unchanged at a constant value.

  As described above, after the “charging upper limit value” is stored and the “charging limit value” is set, the control unit 22 stops the charging operation when the SOC of the vehicle-mounted battery 61 reaches the “charging limit value”. The SOC of the vehicle-mounted battery 61 does not reach the upper limit. Similarly, after storing the “discharge lower limit value” and setting the “discharge limit value”, the control unit 22 stops the discharging operation when the SOC of the vehicle-mounted battery 61 reaches the “discharge limit value”. The SOC of the battery 61 does not reach the lower limit.

  In the present embodiment, the charge limit value is set to a value of the charge upper limit value −5%, and the discharge limit value is set to a value of the discharge lower limit value + 5%. The upper charging limit is approximately the same as the upper limit set by the vehicle controller 63, and the lower discharge limit is approximately the same as the lower limit set by the vehicle controller 63. That is, in the present embodiment, the charging limit value is set to a value of the upper limit value −5%, and the discharging limit value is set to almost the same state as the lower limit value + 5%.

  Therefore, according to the charging / discharging device 20 and the charging / discharging system 1 according to the present embodiment, the number of receptions of the stop signal from the electric vehicle 60 can be reduced without excessively narrowing the SOC band of the vehicle-mounted battery 61.

  The embodiments of the charge / discharge device and the charge / discharge system according to the present invention have been described above, but the present invention is not limited to the above embodiments.

  Regarding the charge / discharge control method performed by the control unit 22, in the above embodiment, the “upper limit of charge” or the “lower limit of discharge” is stored after the reconnection operation of the communication unit 23. Before this, the “upper limit of charge” or the “lower limit of discharge” may be stored.

  For example, the charge / discharge control method performed by the control unit 22 can be changed as shown in FIG. In the charging / discharging control method shown in FIG. 5, the control unit 22 receives the information on the SOC of the vehicle-mounted battery 61 from the vehicle control unit 63 in step S6, and stores the SOC in the storage unit 26 as the “charge upper limit value”. (S6). Next, the control unit 22 sets the “charging limit value” to the charging upper limit value −5% (S7), and thereafter performs the disconnection operation (S3-1) and the reconnection operation (S5).

  Further, in step S10, the control unit 22 receives the information on the SOC of the on-vehicle battery 61 from the vehicle control unit 63, and stores the SOC in the storage unit 26 as the "discharge lower limit value" (S10). Next, the control unit 22 sets the “discharge limit value” to the discharge lower limit value + 5% (S11), and thereafter performs the disconnection operation (S3-2) and the reconnection operation (S9).

  Further, the control unit 22 determines that the first condition is not satisfied in the determination of step S4 (NO in S4), and determines that the second condition is not satisfied in the determination of step S8 (NO in S8). ), And perform a disconnection operation (S3-3). Next, the control unit 22 shifts to the standby state without performing the reconnection operation, storing the charge upper limit value and the discharge lower limit value, and storing the charge / discharge limit value (S12).

  As described above, when the “upper limit value of charge” or “lower limit value of discharge” is stored before the disconnection operation of the communication unit 23, the “upper limit value of charge” is stored in the storage unit 26 after the charging of the vehicle-mounted battery 61 is stopped. The time required to complete is shorter than in the above embodiment. The SOC of the vehicle-mounted battery 61 may decrease with time after charging is stopped. However, according to the charge / discharge control method illustrated in FIG. 5, even if the SOC decreases, the effect is suppressed more than in the above-described embodiment. can do. As a result, the band of the charge / discharge limit value can be made wider than in the above embodiment.

  The “charge limit value” of the present invention may be set to a value smaller than the SOC of the vehicle-mounted battery 61 after the reception of the stop signal. May be set to a value larger than the SOC of the above.

  It is preferable to set how small the charge limit value and how large the discharge limit value should be set according to the capacity of the vehicle-mounted battery 61 and the like. As the charge / discharge limit value approaches the SOC of the vehicle-mounted battery 61 after the reception of the stop signal, the band of the charge / discharge limit value can be broadened. However, depending on the accuracy of the SOC detected by the vehicle control unit 63, the charge / discharge limit value may vary. The value and the upper and lower limits may overlap, and a stop signal may be transmitted again.

  In the above-described embodiment, the disconnection operation is performed when the stop signal from the electric vehicle 60 is received. However, the present invention is not limited to this. When the control unit 22 determines that the stop condition is satisfied, the disconnection operation is performed. May be performed. Specifically, when the control unit 22 can make a determination of only transmitting a stop signal regarding a normal stop based on the information on the on-vehicle battery 61 instead of the vehicle control unit 63, Instead of receiving the stop signal, the control unit 22 may perform the disconnection operation when determining that the stop condition is satisfied. Alternatively, the paralleling operation may be performed when the control unit 22 determines that the stop condition is satisfied at the same time as the reception of the stop signal from the electric vehicle 60. That is, the control unit 22 detects the stop of the charging / discharging operation for the on-vehicle battery 61 and performs the disconnection operation by receiving the stop signal from the electric vehicle 60 and / or by its own determination that the stop condition is satisfied. Good.

  The “power conditioner device” of the present invention may not include the storage battery 30, may include another power generation device in addition to the photovoltaic power generation device 40, or may be replaced with the photovoltaic power generation device 40. Alternatively, another power generation device may be provided.

REFERENCE SIGNS LIST 1 charge / discharge system 10 power conditioner device 11 first converter unit 12 second converter unit 13 inverter unit 14 power conditioner control unit 20 charge / discharge device 21 power conversion unit 22 control unit 23 communication unit (detection unit)
24 charge / discharge control unit 25 limit value setting unit 26 storage unit 30 storage battery 40 solar power generation device 50 load 60 electric vehicle 61 vehicle-mounted battery 62 contactor 63 vehicle control unit

Claims (6)

A power conversion unit that performs a charge / discharge operation on a vehicle-mounted battery of the electric vehicle;
A control unit that controls the power conversion unit;
A charge / discharge device comprising:
The control unit includes:
A detection unit that detects a stop of the charging / discharging operation for the on-vehicle battery and disconnects the connection with the electric vehicle and performs a reconnection operation to restart the connection with the electric vehicle after the disconnection operation. ,
The charging limit value of the vehicle-mounted battery is set to a value smaller than the SOC of the vehicle-mounted battery after the stop detection, while the discharge limit value of the vehicle-mounted battery is set to be larger than the SOC of the vehicle-mounted battery after the stop detection. A limit value setting section for setting a value,
A charge / discharge control unit that stops the charge / discharge operation when the SOC of the on-vehicle battery reaches the charge limit value or the discharge limit value. The limit value setting unit,
When the SOC of the vehicle-mounted battery is equal to or greater than a first threshold and the first condition that the operation of the power conversion unit at the time of the stop detection is a charging operation is satisfied, the SOC of the vehicle-mounted battery after the stop is detected Is stored as a charging upper limit value, while the charging limit value is set to a value smaller than the charging upper limit value,
When the SOC of the vehicle-mounted battery is equal to or less than a second threshold value and the second condition that the operation of the power conversion unit at the time of the stop detection is a discharging operation is satisfied, the SOC of the vehicle-mounted battery after the stop detection is satisfied. 2 is stored as a lower discharge limit, and the discharge limit value is set to a value larger than the lower discharge limit. The charging / discharging device according to claim 2, wherein the limit value setting unit stores the charging upper limit value or the discharging lower limit value after the reconnection operation. The charging / discharging device according to claim 2, wherein the limit value setting unit stores the upper charging limit or the lower discharging limit before the disconnection operation. A power conditioner device, a charge and discharge system including the charge and discharge device according to any one of claims 1 to 4,
The power conditioner device,
A first converter unit connected to the solar power generation device and the charge / discharge device, and configured to supply the generated power of the solar power generation device to the charge / discharge device;
An inverter unit that is connected to the first converter unit and the load, converts DC power output from the first converter unit into AC power, and supplies the AC power to the load;
A charge / discharge system comprising: a power conditioner control unit that controls the first converter unit and the inverter unit. Further including a storage battery,
The power conditioner device,
An operation of being connected to the storage battery, the first converter unit and the inverter unit, and charging the storage battery using the DC power output from the first converter unit under the control of the power conditioner control unit; The charging / discharging system according to claim 5, further comprising a second converter unit that performs an operation of supplying discharge power of the storage battery to the inverter unit.

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