WO2017130564A1

WO2017130564A1 - Charging/discharging system

Info

Publication number: WO2017130564A1
Application number: PCT/JP2016/085788
Authority: WO
Inventors: 隆志原; 信夫森部
Original assignee: 株式会社デンソー
Priority date: 2016-01-26
Filing date: 2016-12-01
Publication date: 2017-08-03
Also published as: JP2017135794A

Abstract

When a connection part (40) connects an electric vehicle (20) and a charger/discharger (11) to each other, a control unit (27) of a charging/discharging system (1) controls each of a first switch (RL1) and a second switch (RL2) to a closed state while providing a time lag between respective closing operations of the first switch (RL1) and the second switch (RL2), and thereby, electrically connects the charger/discharger (11) and a storage battery (21) to each other. When the connection part (40) disconnects the electric vehicle (20) and the charger/discharger (11) from each other, the control unit (27) controls each of the first switch (RL1) and the second switch (RL2) to an open state while providing a time lag between respective opening operations of the first switch (RL1) and the second switch (RL2), and thereby, cancels the electric connection between the charger/discharger (11) and the battery (21).

Description

Charge / discharge system

Cross-reference of related applications

This application is based on Japanese Patent Application No. 2016-12084 filed on January 26, 2016, and claims the benefit of its priority. Which is incorporated herein by reference.

This disclosure relates to a charge / discharge system.

Electric vehicles such as electric vehicles (electric vehicles: EV), small electric vehicles (light electric vehicles: LEV), plug-in hybrid vehicles (plug-in hybrid vehicles: PHV) are generally connected to an external charger / discharger. In the state, power is exchanged between the storage battery and the charger / discharger in the vehicle (for example, Patent Document 1). In this case, the electric vehicle and the charger / discharger are connected using a detachable connector or the like.

In such a charging / discharging system for an electric vehicle, a rapid charging method for shortening the charging time of the storage battery of the vehicle has been studied. Since fast output uses high output and high voltage power, common standards such as CHAdeMO (registered trademark) and Combo have been proposed to ensure the safety of users. By these standards, standardization of connectors used in charge / discharge systems, charging methods, communication methods, etc. are unified. For example, a connector corresponding to the specifications of the common standard includes an electric shock prevention structure such as an electromagnetic lock, a mechanical latch, and a plurality of interface wires.

JP 2014-54022 A

Among the above electric vehicles, a relatively small vehicle such as LEV can use a storage battery having a relatively small output or a low voltage as a power source. For this reason, it is desirable that the safety of the user can be ensured by a simple configuration such as using a ready-made part without using a dedicated product such as a connector corresponding to the specifications of the common standard.

The present disclosure has been made in view of such a problem, and an object thereof is to provide a charge / discharge system that can ensure the safety of the user with a simple configuration.

In order to solve the above problems, a charging / discharging system (1) according to the present disclosure removably connects an electric vehicle (20), a charger / discharger (11), and the electric vehicle and the charger / discharger. A connecting portion (40), and the electric vehicle includes a storage battery (21) and a charge / discharge power line (22A, 22B) that supplies power between the charger / discharger and the storage battery via the connection portion. ), A first switch (RL1) and a second switch (RL2), which are arranged in a permutation on the charge / discharge power line, and switch between interruption and energization of the charge / discharge power line by a switching operation, and the first switch and And a control unit (27) for controlling the operation of the second switch. The control unit, when the electric vehicle and the charger / discharger are connected by the connection unit, the first switch and the first switch and the second switch with a time difference in the closing operation of the first switch and the second switch When the second switch is controlled to be closed, the charger / discharger and the storage battery are electrically connected, and when the electric vehicle and the charger / discharger are disconnected by the connecting portion, the first switch The first switch and the second switch are controlled to be open while causing a time difference in the opening operation of the switch and the second switch, and the electrical connection between the charger / discharger and the storage battery is released. .

With this configuration, it is possible to configure so that no voltage is generated in the receptacle even when the switch is welded, with a simple configuration in which the switch is doubled in the existing charge / discharge circuit. The same safety as a dedicated product such as a corresponding connector can be ensured.

According to the present disclosure, it is possible to provide a charge / discharge system that can ensure the safety of the user with a simple configuration.

FIG. 1 is a diagram illustrating a schematic configuration of a charge / discharge system according to the present embodiment. FIG. 2 is a diagram showing an example of the configuration of the vehicle ECU in FIG. FIG. 3 is a flowchart for explaining an operation at the time of connection between the charge / discharge stand and the electric vehicle in the charge / discharge system according to the present embodiment. FIG. 4 is a timing chart for explaining the operation at the time of connection between the charge / discharge stand and the electric vehicle in the charge / discharge system according to the present embodiment. FIG. 5 is a flowchart for explaining the operation at the time of detachment between the charge / discharge stand and the electric vehicle in the charge / discharge system according to the present embodiment. FIG. 6 is a timing chart for explaining the operation at the time of detachment between the charge / discharge stand and the electric vehicle in the charge / discharge system according to the present embodiment.

Hereinafter, the present embodiment will be described with reference to the accompanying drawings. In order to facilitate the understanding of the description, the same constituent elements in the drawings will be denoted by the same reference numerals as much as possible, and redundant description will be omitted.

First, with reference to FIG.1 and FIG.2, the structure of the charging / discharging system 1 which concerns on this embodiment is demonstrated. The charging / discharging system 1 performs charging / discharging of the storage battery 21 mounted on the electric vehicle 20. As shown in FIG. 1, the charge / discharge system 1 includes a charge / discharge stand 10 and an electric vehicle 20.

The charging / discharging stand 10 is a device that is installed in, for example, a parking lot where the electric vehicle 20 is parked, and controls power exchange with the storage battery 21 of the electric vehicle 20 being parked. The charging / discharging stand 10 charges the storage battery 21 of the electric vehicle 20 with, for example, the power of the system, the electric power stored in the battery, or the electric power output from the solar power generation, and the like. Can be supplied. Moreover, the charging / discharging stand 10 has an external power supply mode, and can supply the electric power discharged from the storage battery 21 of the electric vehicle 20 to the outside at the time of a disaster or a power failure.

The charging / discharging stand 10 includes a charging / discharging device 11 and a charging / discharging device ECU 12 as elements for controlling power transmission / reception with the electric vehicle 20 capable of charging / discharging with a DC voltage. The charger / discharger 11 is a power conversion device that performs bidirectional conversion of power between the electric vehicle 20 and the charge / discharge stand 10. The charger / discharger 11 is connected to a pair of

power lines

13A and 13B, and a charge / discharge coupler 41 is connected to the tips of the

power lines

13A and 13B. The charger / discharger 11 is electrically connected to the storage battery 21 of the electric vehicle 20 via the power lines 13 A and 13 B when the charge / discharge coupler 41 is attached to the receptacle 42 of the electric vehicle 20. Power can be exchanged.

The charger / discharger ECU 12 communicates with the electric vehicle 20 and controls the charger / discharger 11 when charging or discharging with the electric vehicle 20. The charger / discharger ECU 12 is electrically connected to the vehicle ECU 27 of the electric vehicle 20 by allowing the charge / discharge coupler 41 of the charge / discharge stand 10 to be attached to the receptacle 42 of the electric vehicle 20, thereby enabling communication.

The charge / discharge coupler 41 of the charge / discharge stand 10 and the receptacle 42 of the electric vehicle 20 function as a connection part 40 that detachably connects the charge / discharge stand 10 (charge / discharge device 11) and the electric vehicle 20. .

The electric vehicle 20 is a vehicle that supplies electric power stored in the storage battery 21 to the main machine 30 such as a motor and travels by the driving force generated in the main machine 30. Examples of the electric vehicle 20 include an electric vehicle (EV), a small electric vehicle (LEV), a plug-in hybrid vehicle (PHV), and the like. Among these, the LEV is a vehicle that can use the storage battery 21 having a relatively lower output than the common standard such as CHAdeMO (registered trademark) and Combo as a power source. Therefore, the LEV is particularly suitable for the charge / discharge system 1 according to the present embodiment. Yes.

As shown in FIG. 1, the electric vehicle 20 includes a storage battery 21, a vehicle ECU 27 (control unit), a main machine inverter 29, and a main machine 30.

The storage battery 21 is a lithium ion battery for storing electric power for running the electric vehicle 20. The rated voltage of the storage battery 21 is, for example, 72 [V] when the electric vehicle 20 is LEV. Inside electric vehicle 20, a pair of

power lines

22A and 22B (charge / discharge power lines) is provided. When the charge / discharge coupler 41 of the charge / discharge stand 10 is connected to the receptacle 42 of the electric vehicle 20, the power line 22 A has one end connected to the power line 13 A of the charge / discharge stand 10 and the other end connected to the storage battery 21. It has become. In addition, the power line 22 B has one end connected to the power line 13 B of the charging / discharging stand 10 and the other end connected to the storage battery 21.

When the electric vehicle 20 is charged, the DC power output from the charger / discharger 11 of the charging / discharging stand 10 is converted into the

power lines

13A and 13B on the charging / discharging stand 10 side and the power line 22A on the electric vehicle 20 side. , 22B to the storage battery 21. Further, when the electric vehicle 20 is discharged, the DC power output from the storage battery 21 is supplied via the electric power vehicle 20

side power lines

22A and 22B and the charging / discharging stand 10

side power lines

13A and 13B. It is supplied to the charger / discharger 11. That is, the power lines 22 A and 22 B can supply power between the charger / discharger 11 and the storage battery 21 via the connection unit 40.

On the power line 22A, a relay 23 and a relay 25 that switch off and energize the power line 22A by opening and closing operations are installed in a permutation. The relay 23 is provided on the connecting portion 40 (receptacle 42) side of the power line 22A, and the relay 25 is provided on the storage battery 21 side of the power line 22A. Similarly, on the power line 22B,

relays

24 and 26 for switching between interruption and energization of the power line 22A by opening and closing operations are installed in a permutation. The relay 24 is provided on the connection portion 40 (receptacle 42) side of the power line 22B, and the relay 26 is provided on the storage battery 21 side of the power line 22B.

The

relays

23, 24, 25, and 26 are closed when the electric vehicle 20 and the charge / discharge stand 10 are connected by the connecting portion 40 and the storage battery 21 is charged / discharged. Further, when the electric vehicle 20 and the charging / discharging stand 10 are separated by the connecting portion 40, both are opened to prevent voltage application at the receptacle 42. The relay 23 and the relay 24 are configured to operate at the same timing. Hereinafter, the relay 23 and the relay 24 are collectively referred to as a first relay RL1 (first switch). Similarly, the relay 25 and the relay 26 are configured to operate at the same timing. Hereinafter, the relay 25 and the relay 26 are collectively referred to as a second relay RL2 (second switch). The opening / closing operation of the

relays

23, 24, 25, 26 is controlled by the vehicle ECU 27.

One end of a pair of

power lines

28A and 28B (main machine power lines) for supplying power to the main machine 30 of the electric vehicle 20 is connected to a position between the installation position of the second relay RL2 and the storage battery 21 among the

power lines

22A and 22B. Has been. More specifically, one power line 28A is connected to a position between the installation position of the second relay RL2 and the positive electrode side of the storage battery 21 in the power line 22A, and the installation position of the second relay RL2 and the storage battery 21 in the power line 22B. The other power line 28B is connected to a position between the negative electrode side and the other power line 28B. The other ends of the

power lines

28A and 28B are both connected to the main machine inverter 29.

The main machine inverter 29 is a power converter that converts DC power supplied from the storage battery 21 via the

power lines

22A and 22B and the

power lines

28A and 28B into AC power and supplies the AC power to the main machine 30. The main machine 30 is a rotating electrical machine that is driven by electric power supplied from the storage battery 21 such as a motor.

The vehicle ECU 27 performs communication with the charging / discharging stand 10 and operation control of the first relay RL1 and the second relay RL2 when charging / discharging the storage battery 21 with the charging / discharging stand 10. When the charge / discharge coupler 41 of the charge / discharge stand 10 is attached to the receptacle 42 of the electric vehicle 20, the vehicle ECU 27 is electrically connected to the charger / discharger ECU 12 of the charge / discharge stand 10 to enable communication. More specifically, as shown in FIG. 1, the opening / closing operations of the first relay RL1 and the second relay RL2 are individually controlled in response to receiving a charge / discharge coupler connection signal from the charger / discharger ECU 12.

Particularly in the present embodiment, when the electric vehicle 20 and the charging / discharging stand 10 are connected by the connection unit 40, the vehicle ECU 27 causes the first relay RL1 to have a time difference in the closing operation of the first relay RL1 and the second relay RL2. And the second relay RL2 is controlled to be closed. More specifically, first, the second relay RL2 is controlled to be closed, and then the first relay RL1 is controlled to be closed, so that the charger / discharger 11 and the storage battery 21 are electrically connected.

In addition, when the electric vehicle 20 and the charging / discharging stand 10 are separated by the connection unit 40, the vehicle ECU 27 causes the first relay RL1 and the second relay to have a time difference in the opening operation of the first relay RL1 and the second relay RL2. Control RL2 to an open state. More specifically, the first relay RL1 is first controlled to be in the open state, and then the second relay RL2 is controlled to be in the open state, so that the electrical connection between the charger / discharger 11 and the storage battery 21 is released.

An example of a specific configuration of the vehicle ECU 27 is shown in FIG. The vehicle ECU 27 includes a first power conversion device 31, a second power conversion device 32 (power conversion device), a first relay control circuit 33, and a second relay control circuit 34 (switch control circuit).

The first power conversion device 31 and the second power conversion device 32 convert the voltage of the DC power supplied from the DC power supply 36 and output it. In the first power converter 31, one of the pair of input terminals is connected to the positive electrode side of the DC power source 36 by the power line 51A, and the other of the pair of input terminals is connected to the negative electrode side of the DC power source 36 by the power line 51B. Similarly, in the second power conversion device 32, one of the pair of input terminals is connected to the positive electrode side of the DC power source 36 by the power line 53A (first power line), and the other of the pair of input terminals is the power line 53B (second power line). Is connected to the negative electrode side of the DC power source 36.

The first relay control circuit 33 controls the operation of the first relay RL1. The first relay control circuit 33 is connected to one of the pair of output terminals of the first power converter 31 by the power line 52A, and is connected to the other of the pair of output terminals of the first power converter 31 by the power line 52B. It operates by direct current power supplied from the first power converter 31. The first relay control circuit 33 outputs to the first relay RL1 a first relay drive signal for causing the first relay RL1 to perform an opening operation or a closing operation based on various input information such as a charge / discharge coupler connection signal.

The second relay control circuit 34 controls the operation of the second relay RL2. The second relay control circuit 34 is connected to one of the pair of output terminals of the second power converter 32 by the power line 54A (third power line), and is paired by the power line 54B (fourth power line). It is connected to the other output terminal and is operated by DC power supplied from the second power converter 32. The second relay control circuit 34 outputs, to the second relay RL2, a second relay drive signal for causing the second relay RL2 to perform an opening operation or a closing operation based on various input information such as a charge / discharge coupler connection signal. The first relay control circuit 33 and the second relay control circuit 34 are configured by a microcomputer or the like, and are configured as a computer system including a CPU, a ROM, a RAM, and an input / output interface.

The voltages applied to the power line 52A and the power line 54A are respectively supplied to the first relay RL1 and the second relay RL2 as the first relay voltage and the second relay voltage used for driving the first relay RL1 and the second relay RL2. .

The first power conversion device 31, the first relay control circuit 33, and the DC power supply 36 function as a first relay control unit 37 (first control unit) that controls the operation of the first relay RL1. The second power converter 32, the second relay control circuit 34, and the DC power supply 36 function as a second relay control unit 38 (second control unit) that controls the operation of the second relay RL2.

2, the second relay control unit 38 has a holding circuit 35 for holding the operating state of the second relay RL2. The holding circuit 35 includes a diode D1 (first diode), a diode D2 (second diode), a resistor R1, a capacitor C0 (first capacitor), and a capacitor C1 (second capacitor). The diode D1 is provided on the power line 53A in a direction in which current flows from the DC power source 36 to the second power conversion device 32. The resistor R1 and the capacitor C1 are connected in series between the position of the power line 53A between the diode D1 and the input terminal of the second power converter 32 and the power line 53B. The diode D2 is configured such that a current flows toward the power line 53A between an intermediate position between the resistor R1 and the capacitor C1 and a position on the second power converter 32 side from a connection position of the resistor R1 in the power line 53A. It is connected. The capacitor C0 is connected between the power line 54A and the power line 54B.

The second relay control unit 38 has the holding circuit 35 having such a circuit configuration, so that the output of the second relay drive signal and the second relay voltage is continued for a certain period even when there is no power supply from the DC power supply 36. The operation state of the second relay RL2 can be maintained.

Next, with reference to FIG.3 and FIG.4, the operation | movement at the time of the connection of the charging / discharging stand 10 and the electric vehicle 20 in the charging / discharging system 1 which concerns on this embodiment is demonstrated. In the timing chart of FIG. 4, (A) charge / discharge coupler connection signal, (B) charge / discharge permission signal, (C) charge / discharge current, (D) first relay RL1, (E) second relay RL2 over time. It is shown. The flowchart of FIG. 3 is implemented by the vehicle ECU 27 and the charger / discharger ECU 12 at predetermined intervals, for example. Hereinafter, description will be made along the flowchart of FIG. 3 with reference to the timing chart of FIG.

In step S11, the vehicle ECU 27 determines whether or not the lock of the charge / discharge coupler 41 has been detected. The vehicle ECU 27 can detect that the charge / discharge coupler 41 is attached to the receptacle 42 and locked based on the charge / discharge coupler connection signal input from the charger / discharger ECU 12. The charge / discharge coupler connection signal is a voltage value, for example, and is a signal whose voltage value changes between a state where the charge / discharge coupler 41 is locked to the receptacle 42 and a state where the lock state is released. The vehicle ECU 27 can detect the lock of the charge / discharge coupler 41 by reading the voltage change of the charge / discharge coupler connection signal. As a result of the determination in step S11, if the lock of the charge / discharge coupler 41 is detected, the process proceeds to step S12, and if not, the control flow ends.

Here, as shown in FIG. 4A, the charge / discharge coupler connection signal is 0 [V] before time T1, and the charge / discharge coupler 41 is not locked to the receptacle 42. Since the charge / discharge coupler connection signal changes to a positive value after time T1, the vehicle ECU 27 can detect a connection state in which the charge / discharge coupler 41 is locked to the receptacle 42.

In step S12, the vehicle ECU 27 determines whether or not an execution condition for charge / discharge control (charge / discharge operation) between the electric vehicle 20 and the charger / discharger 11 is established. The charging / discharging control execution conditions may include various conditions such as the charging rate of the storage battery 21 and the operating status of the charging / discharging stand 10. As a result of the determination in step S12, if the execution condition is satisfied, the process proceeds to step S13, and if not, this control flow is terminated. In the example of FIG. 4, the charging / discharging control conditions are satisfied after time T2.

In step S13, the vehicle ECU 27 controls the second relay RL2 to be in a closed state (short). For example, the vehicle ECU 27 closes the second relay RL2 after a predetermined first period (T3-T2 in FIG. 4) has elapsed since the time when the charge / discharge control execution condition was satisfied in step S12 (time T2 in FIG. 4). Control. When the process of step S13 is completed, the process proceeds to step S14.

In step S14, the first relay RL1 is controlled to be in a closed state (short circuit) by the vehicle ECU 27. For example, the vehicle ECU 27 closes the first relay RL1 after a predetermined second period (T4-T2 in FIG. 4) has elapsed since the time when the charge / discharge control execution condition was satisfied in step S12 (time T2 in FIG. 4). Control. When the process of step S14 is completed, the process proceeds to step S15.

Here, as shown in FIG. 4E, the second relay RL2 is controlled to the closed state at time T3, and is switched from the open state to the moving state. Further, as shown in FIG. 4D, at the time T4 later by the time t than the time T3, the first relay RL1 is controlled to be in the closed state and switched from the open state to the moving state.

In step S15, charge / discharge control between the electric vehicle 20 and the charger / discharger 11 is started by the charger / discharger ECU 12. Based on the charge / discharge permission signal, the charger / discharger ECU 12 can determine whether the charge / discharge control is permitted. The charge / discharge permission signal is, for example, a voltage value, and is a signal whose voltage value changes depending on whether the charge / discharge permission state is set. The charge / discharge permission signal is a signal generated by mutual communication between the charger / discharger ECU 12 and the vehicle ECU 27, for example, as shown in FIG. The charging / discharging permission signal can output a voltage value indicating a charging / discharging permission state when the charging / discharging control can be performed by both the charging / discharging device ECU 12 and the vehicle ECU 27, and at least of the charging / discharging device ECU 12 and the vehicle ECU 27. On the other hand, when an error occurs and charge / discharge control cannot be performed, a voltage value indicating a charge / discharge stop state can be output. The charger / discharger ECU 12 can detect the charge / discharge permission state by reading the change in the voltage of the charge / discharge permission signal. When the charging / discharging ECU 12 detects the charging / discharging permission state, the charging / discharging ECU 12 controls the charging / discharging device 11 to start charging / discharging control with the storage battery 21, and the

power lines

13A, 13B on the charging / discharging stand 10 side and electric A charge / discharge current flows through the

power lines

22A and 22B on the vehicle 20 side. When the process of step S15 is completed, this control flow ends.

Here, as shown in FIG. 4B, at time T5 after the first relay RL1 and the second relay RL2 are controlled to be closed, the charge / discharge permission signal changes from 0 [V] to a positive value. Transition from the charge / discharge stop state to the charge / discharge permission state. Then, the charger / discharger ECU 12 starts the operation of the charger / discharger 11 at time T6, and the charging current from the charger / discharger 11 is increased to a predetermined value and supplied to the storage battery 21 at time T7.

Next, with reference to FIG. 5 and FIG. 6, the operation when the charge / discharge station 10 and the electric vehicle 20 are detached in the charge / discharge system 1 according to the present embodiment will be described. The schematic configuration of the timing chart of FIG. 6 is the same as the timing chart of FIG. Hereinafter, description will be made along the flowchart of FIG. 5 with reference to the timing chart of FIG.

In step S21, the vehicle ECU 27 determines whether or not unlocking of the charge / discharge coupler 41 is detected. The vehicle ECU 27 can detect the unlocking of the charge / discharge coupler 41 based on the charge / discharge coupler connection signal input from the charger / discharger ECU 12. More specifically, when the proximity switch provided in the charge / discharge coupler 41 is pressed, the portion latched by the receptacle 42 is released, so that the charge / discharge coupler 41 can be removed from the receptacle 42. The vehicle ECU 27 can detect the unlocking of the charge / discharge coupler 41 by reading the change in voltage of the charge / discharge coupler connection signal at this time. As a result of the determination in step S21, if unlocking of the charge / discharge coupler 41 is detected, the process proceeds to step S22, and if not, this control flow ends.

Here, as shown in FIG. 6A, the charging / discharging coupler connection signal is a positive value before time T8, and the charging / discharging coupler 41 is locked to the receptacle 42. Since the charge / discharge coupler connection signal decreases and changes stepwise at time T8, the vehicle ECU 27 can detect the removal preparation state in which the charge / discharge coupler 41 is unlocked and is still inserted into the receptacle 42.

In step S22, charging / discharging control between the electric vehicle 20 and the charger / discharger 11 is stopped by the charger / discharger ECU 12. The vehicle ECU 27 changes the charge / discharge permission signal to the charge / discharge stop state in response to the detection of unlocking in step S21. The charger / discharger ECU 12 controls the charger / discharger 11 according to the change in the charge / discharge permission signal, and stops the charge / discharge control with the storage battery 21. When the process of step S22 is completed, the process proceeds to step S23.

In step S23, the vehicle ECU 27 determines whether or not the charge / discharge current has been reduced to 0 [A]. Due to the stop operation of the charge / discharge control in step S22, the charge / discharge current flowing through the

power lines

22A, 22B gradually decreases to 0 [A]. The vehicle ECU 27 can detect that the charge / discharge current has been reduced to 0 [A] by monitoring the transition of the charge / discharge current at this time. If the charge / discharge current is reduced to 0 [A] as a result of the determination in step S22, the process proceeds to step S23. Otherwise, the process waits until the charge / discharge current is reduced to 0 [A].

Here, as shown in FIG. 6B, at time T8, as the charge / discharge permission signal changes from the charge / discharge permission state to the charge / discharge stop state, the charge / discharge current is changed as shown in FIG. It begins to decrease gradually and decreases to 0 [A] at time T9.

In step S24, the vehicle ECU 27 controls the first relay RL1 to be in an open state (open). For example, the vehicle ECU 27 performs a predetermined third period (T10-T8 in FIG. 6) from the time when charging / discharging control between the electric vehicle 20 and the charger / discharger 11 is stopped in step S22 (time T8 in FIG. 6). After the elapse, the first relay RL1 is controlled to be in an open state. When the process of step S24 is completed, the process proceeds to step S25.

In step S25, the vehicle ECU 27 controls the second relay RL2 to be in an open state (open). For example, the vehicle ECU 27 performs a predetermined fourth period (T11-T8 in FIG. 6) from the time when charging / discharging control between the electric vehicle 20 and the charger / discharger 11 is stopped in step S22 (time T8 in FIG. 6). After the elapse, the second relay RL2 is controlled to be in an open state. When the process of step S25 is completed, the charge / discharge coupler 41 can be safely removed from the receptacle 42, and the present control flow ends.

Here, as shown in FIG. 6D, at time T10, the first relay RL1 is controlled to be in the open state, and is switched from the moving state to the released state. Further, as shown in FIG. 6E, at time T11 which is later by time t than time T10, the second relay RL2 is controlled to be in the open state, and is switched from the moving state to the released state. Thereafter, at time T12, the charge / discharge coupler connection signal is switched from the removal preparation state to the unconnected state, and the charge / discharge coupler 41 is in a state where it can be safely removed from the receptacle 42.

Next, effects of the charge / discharge system 1 according to the present embodiment will be described.

In the charging / discharging system 1 of the present embodiment, the vehicle ECU 27 of the electric vehicle 20 includes the first relay RL1 when the electric vehicle 20 and the charging / discharging stand 10 are connected by the connection unit 40 (the charging / discharging coupler 41 and the receptacle 42). The charging / discharging stand 10 is charged / discharged by controlling the first relay RL1 and the second relay RL2 to be closed while giving a time difference to the closing operation of the (relays 23, 24) and the second relay RL2 (relays 25, 26). Electric appliance 11 and storage battery 21 of electric vehicle 20 are electrically connected. Further, when the electric vehicle 20 and the charging / discharging stand 10 are separated by the connecting portion 40, the first relay RL1 and the second relay RL2 are opened while a time difference is provided in the opening operation of the first relay RL1 and the second relay RL2. The electrical connection between the charger / discharger 11 and the storage battery 21 is released. Here, the

relays

23 and 24 of the first relay RL1 and the

relays

25 and 26 of the second relay RL2 are installed in permutations on the

power lines

22A and 22B in the electric vehicle 20, respectively.

In the present embodiment, the

relays

23 and 24 of the first relay RL1 are provided on the connection part 40 side of the

power lines

22A and 22B, and the

relays

25 and 26 of the second relay RL2 are on the storage battery 21 side of the

power lines

22A and 22B. Is provided. When the electric vehicle 20 and the charging / discharging stand 10 are electrically connected by the connection unit 40, the vehicle ECU 27 first controls the second relay RL2 to the closed state, and then controls the first relay RL1 to the closed state. Then, the charger / discharger 11 and the storage battery 21 are electrically connected. Further, when the electric vehicle 20 and the charging / discharging stand 10 are separated from each other by the connecting portion 40, the first relay RL1 is first controlled to be opened, and then the second relay RL2 is controlled to be opened and charged. The electrical connection between the electric appliance 11 and the storage battery 21 is released.

With the above configuration, when the charge / discharge coupler 41 and the receptacle 42 of the connection unit 40 are removed and the storage battery 21 of the electric vehicle 20 and the charger / discharger 11 of the charge / discharge stand 10 are disconnected, the relay 23 on the power lines 22A and 22B. ˜26 are opened. Thereby, it is possible to cut off the energization of the

power lines

22A and 22B, and it is possible to prevent the voltage from being applied to the receptacle 42 of the electric vehicle 20 provided at the ends of the

power lines

22A and 22B and exposed to the outside at this time.

Here, contact welding may generally occur in the relays 23 to 26. For example, when the contact is opened in a state where current is flowing through the contact, the contact resistance of the contact surface increases due to the generated arc heat, and the contact surface melts and welds. Contact welding may also occur due to continuous arcs caused by chattering or vibration with high frequency switching. When contact welding occurs, the relay contact does not open, resulting in a return failure. If contact welding occurs in all of the relays 23 to 26 on the circuit, the circuit cannot be sufficiently cut off, and the voltage is output to the receptacle 42, which impairs safety such as electric shock of the user. There is a fear.

In this embodiment, the

relays

23, 24, 25, and 26 provided on the power line 22 are divided into two groups of the first relay RL1 and the second relay RL2, and a time difference is given to the opening / closing operation for each group, and the opening / closing timing is shifted. ing. Thereby, even when one relay group of the first relay RL1 and the second relay RL2 is welded, the other relay group can avoid welding, so that all the relays can be prevented from being welded simultaneously. Therefore, even if a situation occurs where contact welding occurs in one relay group, the other relay group can maintain an operable state, so that the

power lines

22A and 22B can be reliably cut off. As a result, in a state where the charge / discharge coupler 41 and the receptacle 42 of the connection part 40 are removed, it is possible to reliably prevent voltage from being output to the receptacle 42 exposed to the outside, and to ensure the safety of the user.

In addition, common standards such as CHAdeMO (registered trademark) and Combo related to the charging method for electric vehicles also standardize the connector standard, charging method and communication method used in the charge / discharge system in order to ensure such safety. Is planned. However, a connector corresponding to the specifications of this common standard is defined to have an electric shock prevention structure such as an electromagnetic lock, a mechanical latch, and a plurality of interface wires, and requires a complicated configuration. On the other hand, the present embodiment can be configured such that no voltage is generated in the receptacle even when the relay is welded by a simple configuration in which the relays 23 to 26 are provided in duplicate in the existing charge / discharge circuit. The same safety as a dedicated product such as a connector corresponding to the specifications of the common standard can be ensured. As described above, as a result, the charge / discharge system 1 of the present embodiment can ensure the safety of the user with a simple configuration.

In the charge / discharge system 1 of the present embodiment, the vehicle ECU 27 includes a first relay control unit 37 that controls the operation of the first relay RL1, a second relay control unit 38 that controls the operation of the second relay RL2, The second relay control unit 38 includes a holding circuit 35 that can hold the operation state of the second relay RL2 for a certain period of time.

As described with reference to FIG. 2, in the present embodiment, the first relay control unit 37 and the second relay control unit 38 are both configured as a part of a single vehicle ECU 27, and are shared by a common DC power source 36. It works. For this reason, if the power supply from the DC power supply 36 is suddenly stopped, a situation may occur in which both the first relay RL1 and the second relay RL2 cannot operate. At this time, when both the first relay control unit 37 and the second relay control unit 38 do not have the holding circuit 35, a state in which the first relay RL1 and the second relay RL2 simultaneously transition to the closed state is considered. Therefore, the first relay RL1 and the second relay RL2 may be welded at the same time.

On the other hand, in the present embodiment, only one of the first relay control unit 37 and the second relay control unit 38 has the holding circuit 35 so that the DC power supply 36 suddenly Even if the situation in which the power supply is stopped occurs, the second relay control unit 38 can continue the operation control of the second relay RL2 for a certain period after the power supply is stopped. Therefore, in this embodiment, even when the power supply to the first relay control unit 37 and the second relay control unit 38 is both stopped or reduced, the opening operation of the first relay RL1 and the second relay RL2 and It is possible to give a time difference to the closing operation and appropriately shift the operation timing. Thereby, it is possible to more reliably prevent the first relay RL1 and the second relay RL2 from simultaneously welding the contacts, and the electrical connection between the charger / discharger 11 and the storage battery 21 can be reliably released.

Moreover, in the charge / discharge system 1 of the present embodiment, the electric vehicle 20 is preferably an LEV (Light Electric Vehicle). A relatively small vehicle such as LEV among the electric vehicles 20 can use a storage battery having a relatively smaller output or a lower voltage than the common standard as a power source. For this reason, the user's safety is ensured with a simple configuration by the charge / discharge system 1 according to the present embodiment, without using a dedicated product such as a connector corresponding to the specifications of the above-mentioned common standard in the charge / discharge system. The effect of the present embodiment can be maximized.

The embodiment has been described above with reference to specific examples. However, the present disclosure is not limited to these specific examples. Those in which those skilled in the art appropriately modify the design of these specific examples are also included in the scope of the present disclosure as long as they have the features of the present disclosure. Each element included in each of the specific examples described above and their arrangement, conditions, shape, and the like are not limited to those illustrated, and can be changed as appropriate. Each element included in each of the specific examples described above can be appropriately combined as long as no technical contradiction occurs.

In the above embodiment, the first relay control unit 37 and the second relay control unit 38 are both configured as a part of a single vehicle ECU 27 and are operated by a common DC power source 36. Each of the first relay control unit 37 and the second relay control unit 38 may be configured as a part of a different ECU, and may be configured to operate individually by different power sources.

In the above embodiment, the configuration in which the holding circuit 35 is provided only in the second relay control unit 38 is illustrated, but at least one of the first relay control unit 37 and the second relay control unit 38 may include the holding circuit 35. That's fine. For example, contrary to the above embodiment, the holding circuit 35 may be provided in the first relay control unit 37, or may be provided in both the first relay control unit 37 and the second relay control unit 38 to hold the operation state. It is good also as a structure which makes duration differ. Of the first relay control unit 37 and the second relay control unit 38, the one that is turned on first when the charge / discharge coupler 41 is mounted (switched to the closed state) and turned off later (when switched to the open state) when removed. A holding circuit 35 is preferably provided in the control unit of the relay. For this reason, in the above-described embodiment, the holding circuit 35 is provided in the second relay control unit 38 that controls the second relay RL2 that is turned on first when the charge / discharge coupler 41 is attached and turned off later when the charge / discharge coupler 41 is removed.

Further, the circuit configuration of the holding circuit 35 may be a circuit configuration other than that illustrated in FIG. 2 as long as the function of holding the operation state of the relay to be controlled can be exhibited. For example, in the above embodiment, the holding circuit 35 exemplifies a configuration including the capacitor C0 provided on the rear stage side (second relay control circuit 34 side) of the second power converter 32, but the capacitor C0 is excluded, It is good also as only the diode D1, the diode D2, resistance R1, and the capacitor | condenser C1 provided in the front | former stage side (DC power supply 36 side) of 2 power converter devices 32. In addition, the holding circuit 35 can extend the time during which the operation state of the relay can be held by including the capacitor C0.

In addition, the opening / closing operation of the first relay RL1 and the second relay RL2 only needs to have a time difference in the opening / closing timing of both, and the order may be changed from the above embodiment, and the time difference t may be increased or decreased as appropriate.

Further, the installation positions of the first relay RL1 and the second relay RL2 are different from the configuration in which the first relay RL1 and the second relay RL2 are collectively installed on the connection unit 40 side from the connection positions of the

power lines

28A and 28B on the

power lines

22A and 22B as in the above embodiment. You may change it. For example, both the first relay RL1 and the second relay RL2 may be collectively installed on one of the storage battery 21 side from the connection position of the

power lines

28A and 28B on the

power lines

22A and 22B. Alternatively, the

power lines

28A and 28B are connected to a position between the installation position of the first relay RL1 and the installation position of the second relay RL2 in the

power lines

22A and 22B, whereby the first relay RL1 is connected to the

power lines

28A and 28B. The connection part 40 side and the second relay RL2 from the connection position may be separately installed on the storage battery 21 side. The number of relays included in the first relay RL1 and the second relay RL2 may be other than two.

Claims

An electric vehicle (20);
A charger / discharger (11);
A connection part (40) for detachably connecting the electric vehicle and the charger / discharger;
Comprising
The electric vehicle is
A storage battery (21);
Charge / discharge power lines (22A, 22B) for supplying power between the charger / discharger and the storage battery via the connection part,
A first switch (RL1) and a second switch (RL2) that are installed in a permutation on the charge / discharge power line and switch between interruption and energization of the charge / discharge power line by a switching operation;
A control unit (27) for controlling operations of the first switch and the second switch;
With
The controller is
When the electric vehicle and the charger / discharger are connected by the connecting portion, the first switch and the second switch are provided with a time difference in the closing operation of the first switch and the second switch. Control to a closed state, electrically connect the charger / discharger and the storage battery,
When the electric vehicle and the charger / discharger are separated from each other by the connecting portion, the first switch and the second switch are opened with a time difference in the opening operation of the first switch and the second switch. Controlling the open state to release the electrical connection between the battery charger and the storage battery,
Charge / discharge system (1).
The controller is
A first control unit (37) for controlling the operation of the first switch;
A second control unit (38) for controlling the operation of the second switch,
At least one of the first control unit and the second control unit has a holding circuit (35) that can hold the operating state of the switch for a certain period of time.
The charge / discharge system according to claim 1.
The first control unit and the second control unit include a DC power source (36), a power converter (31, 32), and a switch control circuit (33, 34).
In the power converter, one of a pair of input terminals is connected to the positive side of the DC power supply by a first power line (53A), and the other of the pair of input terminals is a negative side of the DC power supply by a second power line (53B). Connected with
The switch control circuit is connected to one of the pair of output terminals of the power converter by a third power line (54A), and connected to the other of the pair of output terminals of the power converter by a fourth power line (54B). And
The holding circuit includes a first diode (D1), a second diode (D2), a resistor (R1), a first capacitor (C0), and a second capacitor (C1).
The first diode is provided in a direction in which a current flows from the DC power source to the power converter on the first power line,
The resistor and the second capacitor are connected in series between a position of the first power line between the first diode and an input terminal of the power converter, and the second power line.
The second diode is directed toward the first power line between an intermediate position between the resistor and the second capacitor and a position on the power converter side from a connection position of the resistor in the first power line. Connected to allow current to flow,
The first capacitor is connected between the third power line and the fourth power line.
The charge / discharge system according to claim 2.
The first switch is provided on the connection part side of the charge / discharge power line, and the second switch is provided on the storage battery side of the charge / discharge power line,
Main machine power lines (28A, 28B) for supplying power to the main machine (30) of the electric vehicle are connected to a position between the charge / discharge power line between the second switch and the storage battery.
The charge / discharge system according to any one of claims 1 to 3.
The controller is
When the electric vehicle and the charger / discharger are electrically connected by the connecting portion, the second switch is controlled to be closed first, and then the first switch is controlled to be closed. , Electrically connecting the charger / discharger and the storage battery,
When the electric vehicle and the charger / discharger are separated from each other by the connecting portion, the first switch is first controlled to be in an open state, and then the second switch is controlled to be in an open state. Disconnect the electrical connection between the discharger and the storage battery,
The charge / discharge system according to claim 4.
The controller is
When the electric vehicle and the charger / discharger are electrically connected by the connecting portion, the first time (T2) from when the implementation condition of the charge / discharge operation between the electric vehicle and the charger / discharger is satisfied. The second switch is controlled to be closed after the period (T3-T2) elapses, and the first switch is turned on after the elapse of a second period (T4-T2) longer than the first period from the time when the execution condition is satisfied. Control to the closed state,
When the electric vehicle and the charger / discharger are separated from each other by the connecting portion, the third period (T10-T8) from the time (T8) when charging / discharging control between the electric vehicle and the charger / discharger is stopped. ) After the elapse of time, the first switch is controlled to be in the open state, and after the fourth period (T11-T8) longer than the third period from the time when the charge / discharge control is stopped, the second switch is set in the open state. Control,
The charge / discharge system according to claim 5.
The charge / discharge system according to any one of claims 1 to 6, wherein the electric vehicle is a LEV (Light Electric Vehicle).