JP2014226014A - Power conversion system and connector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power conversion system capable of detecting problem on a switch provided to an electric vehicle and a connector used therefor.SOLUTION: A power conversion system 10 includes: a first switch 31 disposed in a power feed line 5 in a connector 3; and a detection circuit 32 disposed in a power feed line 5 in an electric vehicle 4 for detecting problem on a second switch 43. In the connector 3, the detection circuit 32 has a measurement section 321 that measures voltage values at measuring points P1 and P2 which are set at the side closer to the electric vehicle 4 than the first switch 31 in the power feed line 5 with the second switch 43 opened. The detection circuit 32 is configured to detect problem based on the measurement result by the measurement section 321.

Description

  The present invention relates to a power conversion system to which an electric vehicle equipped with a storage battery is connected, and a connector used therefor.

  2. Description of the Related Art In recent years, attention has been paid to an electric vehicle that charges a storage battery mounted on a vehicle using a charger outside the vehicle and travels using electric energy stored in the storage battery because of resource restrictions and environmental considerations. . Examples of this type of electric vehicle include an electric vehicle (EV) that travels by the output of the electric motor, and a plug-in hybrid vehicle (PHEV) that travels by combining the output of the engine and the output of the electric motor.

  In order to charge these electric vehicles, generally, a charger / discharger including a cable extending from the main body and a connector (charge / discharge connector) for connecting the cable to the vehicle is used (for example, see Patent Document 1). . In the charger / discharger described in Patent Literature 1, when the current value of the current flowing through the cable is equal to or greater than a predetermined value, a switch (electromagnetic switch) that interrupts the current is provided in the connector. Further, the electric vehicle is provided with a contactor as a current limiting means, and the storage battery is connected to the connector via the contactor.

JP 2013-31348 A

  However, the charger / discharger described in Patent Document 1 does not have a function of detecting the presence or absence of an abnormality in a switch (contactor) provided in the electric vehicle, and an abnormality such as welding occurs in the switch in the electric vehicle. However, appropriate measures such as notification to the user cannot be taken immediately.

  The present invention has been made in view of the above-described reasons, and an object thereof is to provide a power conversion system capable of detecting the presence or absence of abnormality of a switch provided in an electric vehicle, and a connector used therefor.

  The power conversion system of the present invention is connected to a power conversion device and the power conversion device via a cable, and is detachably attached to a connection port of an electric vehicle on which a storage battery is mounted. A protective device that includes at least one of a switch and a fuse and is inserted into the power supply path in the connector, and a power supply path in the electric vehicle. A detection circuit that detects whether there is an abnormality in the vehicle switch inserted in the vehicle, wherein the detection circuit uses a voltage value at a measurement point set on the electric vehicle side from the protection device in the power feeding path. The connector has a measuring unit that performs measurement with the switch opened, and is configured to detect the presence or absence of the abnormality based on the measurement result of the measuring unit.

  In this power conversion system, the detection circuit compares the voltage value measured by the measurement unit with a predetermined threshold value, and determines that the vehicle switch is abnormal when the voltage value exceeds the threshold value. It is desirable to have a determination unit.

  In this power conversion system, it is more preferable that the detection circuit includes the determination unit and a notification unit that transmits a binary signal representing a determination result of the determination unit to the power conversion device.

  In this power conversion system, it is more preferable that the detection circuit has a discharge part in the connector for discharging charges accumulated in a capacitive component on the power conversion device side from the vehicle switch in the power supply path.

  In this power conversion system, it is more preferable that the measurement unit is also used as the discharge unit.

  The connector of the present invention is used in any one of the power conversion systems described above.

  In the present invention, the connector has a measurement unit that measures the voltage value of the measurement point set on the electric vehicle side from the protection device in the power supply path with the vehicle switch open, and the measurement of the measurement unit Based on the result, it is configured to detect whether or not the vehicle switch is abnormal. Therefore, there exists an advantage that the presence or absence of abnormality of the switch provided in the electric vehicle can be detected.

1 is a schematic block diagram of a power conversion system according to Embodiment 1. FIG. 1 is a schematic circuit diagram of a connector according to Embodiment 1. FIG. It is explanatory drawing of operation | movement of the power conversion system which concerns on Embodiment 2. FIG. It is a schematic block diagram of the power conversion system which concerns on Embodiment 3.

  In the following embodiment, a power conversion system to which an electric vehicle equipped with a storage battery is connected and a connector used for the power conversion system will be described.

  An electric vehicle charges a storage battery mounted on the vehicle using a charger outside the vehicle, and travels using electric energy stored in the storage battery. In the following, an electric vehicle (EV) that travels by the output of an electric motor is taken as an example of an electric vehicle. However, the electric vehicle is not limited to an electric vehicle, and for example, a plug-in hybrid vehicle that travels by combining an engine output and an electric motor output. (PHEV) may be used.

  In the following embodiment, the power conversion system is configured to be used for both charging and discharging the storage battery of the electric vehicle by performing power conversion in both directions.

  In other words, the power conversion system converts AC power supplied from a commercial power source (system power source) or a power generation facility such as a solar power generation facility attached to a house to DC power when charging the storage battery, and converts the converted power. The battery is charged by supplying to the electric vehicle. At the time of discharging the storage battery, the power conversion system converts the DC power discharged from the storage battery into AC power, and supplies the converted power to the house to supply power to the equipment and facilities in the house V2H (Vehicle to Home). However, the power conversion system only needs to be configured to transfer power to and from the storage battery, and may be configured to perform only one of charging and discharging of the storage battery.

  In the following, a case where the CHAdeMO (registered trademark) system is adopted as a storage battery charging system will be described as an example. In this charging method, an electronic control unit (ECU) mounted on the electric vehicle calculates a charging current value according to the state of the storage battery such as the remaining amount and temperature. The power conversion system receives an instruction of a charging current value from an electric vehicle by CAN (Controller Area Network) communication, and controls an output current value according to the instruction.

  However, the present invention is not limited to this example, and the power conversion system and connector according to the following embodiment can be applied to other charging methods. Furthermore, the device to which the connector is connected is not limited to an electric vehicle as long as it is a device equipped with a storage battery and having a switch as a vehicle switch in a power supply path, and may be a stationary power storage device, for example. .

(Embodiment 1)
As shown in FIG. 1, the power conversion system 10 of this embodiment includes a power conversion device 1 and a connector 3 connected to the power conversion device 1 via a cable 2. The connector 3 is detachably attached to the connection port 42 of the electric vehicle 4 on which the storage battery 41 is mounted, thereby forming the power feeding path 5 between the power conversion device 1 and the storage battery 41.

  The power conversion system 10 includes at least one of a switch and a fuse. The protection device inserted in the power supply path 5 in the connector 3 and the vehicle switch inserted in the power supply path 5 in the electric vehicle 4 are abnormal. And a detection circuit 32 for detecting. In the present embodiment, a switch (first switch 31) provided in the connector 3 will be described as a protection device, and a second switch 43 provided in the electric vehicle 4 will be described as a vehicle switch. .

  The detection circuit 32 measures the voltage value at the measurement points P <b> 1 and P <b> 2 set on the electric vehicle 4 side from the first switch 31 in the power supply path 5 with the second switch 43 opened. Is provided in the connector 3. The detection circuit 32 is configured to detect the presence or absence of abnormality based on the measurement result of the measurement unit 321.

  The detection circuit 32 compares the voltage value measured by the measurement unit 321 with a predetermined threshold value, and determines that the second switch (vehicle switch) 43 is abnormal when the voltage value exceeds the threshold value. Part 322. Furthermore, the detection circuit 32 includes a determination unit 322 and a notification unit 323 that transmits a binary signal representing the determination result of the determination unit 322 to the power conversion device 1.

  The protection device inserted in the power supply path 5 in the connector 3 may be composed of at least one of a switch and a fuse, and is not limited to the first switch 31 but is a fuse or a combination of a switch and a fuse. May be used as a protective device. Examples of the combination of the switch and the fuse here include an aspect in which the switch and the fuse are connected in series.

  Hereinafter, a specific configuration of the power conversion system 10 of the present embodiment will be described.

  The power conversion device 1 has a main circuit 11 that performs power conversion when the storage battery 41 is charged and discharged. The main circuit 11 is connected to the power supply path 5, and is electrically connected to the storage battery 41 via the power supply path 5 in a state where the connector 3 is attached to the connection port 42 of the electric vehicle 4. When the storage battery 41 is charged, the main circuit 11 converts the power supplied from a commercial power source or the like into DC power of, for example, 50 to 600 V and supplies it to the electric vehicle 4. When the storage battery 41 is discharged, the main circuit 11 uses the discharge power from the storage battery 41, for example. It is converted to 100V AC power and supplied to the house.

  Furthermore, the power conversion device 1 includes a communication unit 12 that performs communication with the electric vehicle 4 and a notification unit 13 that will be described later. The communication part 12 transmits a control signal bidirectionally between the electric vehicles 4 by CAN communication, for example.

  The power conversion device 1 may be a wall-mounted type that is attached to the wall of a building, or may be a stationary type that is installed on the ground.

  The cable 2 has a pair of power supply lines 21 and 22 that constitute a part of the power supply path 5. The pair of power lines 21 and 22 are used for power supply from the main circuit 11 to the storage battery 41 during charging and power supply from the storage battery 41 to the main circuit 11 during discharge. Between the main circuit 11 and the storage battery 41, direct-current power with the power supply line 21 as the high potential side (positive electrode) and the power supply line 22 as the low potential side (negative electrode) is exchanged.

  In addition to the pair of power supply lines 21 and 22, the cable 2 has a pair of CAN signal lines (not shown) and five analog control lines (not shown) used for transmission of control signals. Yes. In FIG. 1, these CAN signal lines and analog control lines are collectively referred to as a communication line 23. In a state where the connector 3 is attached to the connection port 42 of the electric vehicle 4, the communication line 23 is connected to the electric vehicle 4 via the connector 3, and the communication unit 12 of the power conversion device 1 communicates with the electric vehicle 4 through the communication line 23. Can communicate with each other.

  The connector 3 is connected to the tip of the cable 2 and is detachably attached to an inlet as a connection port 42 provided in the electric vehicle 4. The connector 3 has a contact part 33 electrically connected to the cable 2, and the power supply lines 21 and 22 and the communication line 23 of the cable 2 are connected by electrically connecting the contact part 33 to the connection port 42. Is electrically connected to the electric vehicle 4. Therefore, the connector 3 forms the power feeding path 5 between the power conversion device 1 and the storage battery 41 in a state of being attached to the connection port 42. The power feeding path 5 is a pair of electric paths composed of a high potential side and a low potential side. Below, among the feed paths 5 formed between the power converter 1 and the storage battery 41, the feed path 5 in the connector 3 is the first feed path 51, and the feed path 5 in the electric vehicle 4 is the second feed path 5. The power supply path 52 is used.

  The connector 3 includes a latch mechanism (not shown) that mechanically holds the state of being attached to the connection port 42 of the electric vehicle 4 and a lock mechanism (not shown) that restricts the operation of the latch mechanism. (Not shown). The connector 3 prohibits the latch mechanism from being released when the storage battery 41 is charged / discharged, thereby preventing the latch mechanism from being released from the connection port 42.

  The connector 3 forms a first power supply path 51 between the cable 2 and the contact portion 33, and a first switch 31 as a protection device inserted into the first power supply path 51 is provided in the housing. doing. In the present embodiment, the first switch 31 has a first contact 311 inserted on the high potential side of the first power supply path 51 and a second contact 312 inserted on the low potential side. This is a double-sided type switch capable of opening / closing (ON / OFF) each of the first contact 311 and the second contact 312. However, the first switch 31 is not limited to the double-cut type, and includes a first contact 311 inserted on the high potential side of the first power supply path 51 and a second contact 312 inserted on the low potential side. It may be a single-cut type switch having only one of them.

  The first switch 31 includes a solenoid 313 (see FIG. 2) as a driving device that opens and closes each of the first contact 311 and the second contact 312. The first switch 31 is normally closed. When the solenoid 313 is not energized, the first and second contacts 311 and 312 are closed (on state), and when the solenoid 313 is energized. Both contacts 311 and 312 are in an open state (off state).

  The connector 3 includes a drive unit 34 (see FIG. 2) that drives the solenoid 313, and a thermistor 35 (see FIG. 2) as a detection element that detects the temperature of the contact unit 33. When the temperature detected by the thermistor 35 exceeds a predetermined temperature, the drive unit 34 drives the solenoid 313 to open the first switch 31.

  The connector 3 closes both the first and second contacts 311 and 312 when the contact portion 33 is connected to the connection port 42, and both contact points when the contact portion 33 is not connected to the connection port 42. A mechanical opening / closing mechanism (not shown) for opening 311 and 312 is provided. Further, in the present embodiment, the first switch 31 trips when an overcurrent continues to flow through the first power supply path 51 for a predetermined time or longer or when a short-circuit current flows through the first power supply path 51. And it functions also as a circuit breaker which interrupts | blocks a circuit by becoming an open state.

  In the present embodiment, the connector 3 further includes a detection circuit 32 that detects whether or not the second switch (vehicle switch) 43 provided in the electric vehicle 4 is abnormal. The configuration of the detection circuit 32 will be described later.

  The connector 3 generates an operating power supply from an operating voltage (for example, DC 12V) supplied from the power conversion device 1 via the communication line 23, and supplies a power supply circuit (not shown) to each unit (detection circuit 32 or the like). )have.

  On the other hand, the electric vehicle 4 forms a second power supply path 52 between the connection port 42 and the storage battery 41, and has a second switch 43 as a vehicle contactor inserted into the second power supply path 52. doing. In the present embodiment, the second switch 43 has a first contact 431 inserted on the high potential side of the second power supply path 52 and a second contact 432 inserted on the low potential side. This is a double-sided type switch that can open and close each of the first contact 431 and the second contact 432. As in the case of the first switch 31, the second switch 43 is not limited to the double-cut type, and the first contact 431 inserted on the high potential side of the second power feeding path 52 and the low potential. A single-sided type switch having only one of the second contact 432 inserted on the side may be used.

  The second switch 43 is controlled to be opened and closed by an electronic control unit (not shown) of the electric vehicle 4. The electronic control unit basically receives the notification from the power conversion system 10 when starting the charging / discharging of the storage battery 41, closes the second switch 43, and ends the charging / discharging of the storage battery 41. The second switch 43 is configured to open. Thereby, the connection port 42 is connected to the storage battery 41 when the storage battery 41 is charged and discharged, and is electrically disconnected from the storage battery 41 except when the storage battery 41 is charged and discharged.

  Next, the charging operation (charging flow) of the storage battery 41 in the power conversion system 10 of the present embodiment will be briefly described.

  After the connector 3 is connected to the connection port 42, the power conversion system 10 starts a charging flow by performing a predetermined operation for starting charging with respect to an operation unit (not shown). A charging start signal is transmitted to the vehicle 4. When receiving the charge start signal, the electronic control unit of the electric vehicle 4 starts CAN communication with the power conversion system 10 and exchanges data such as the capacity of the storage battery 41.

  When the preparation for charging is completed, the electronic control unit of the electric vehicle 4 transmits a charge permission signal to the power conversion system 10. When the power conversion system 10 receives the charge permission signal, the power conversion system 10 drives the lock mechanism of the connector 3 by causing the drive current to flow from the power conversion device 1 to the connector 3 to be in the locked state. Thereafter, the power conversion system 10 notifies the electronic control unit of the electric vehicle 4 of the completion of preparation for charging.

  When receiving the notification from the power conversion system 10, the electronic control unit of the electric vehicle 4 closes the second switch 43 and instructs the power conversion system 10 about the charging current value. Thereby, the power conversion system 10 starts current output and charges the storage battery 41.

  When the capacity of the storage battery 41 reaches a specified value, the electronic control unit of the electric vehicle 4 transmits a stop request to the power conversion system 10. Thereafter, when the electronic control unit of the electric vehicle 4 confirms that the charging current has decreased to a predetermined value or less, it opens the second switch 43. When receiving the stop request, the power conversion system 10 stops the current output, sets the locking mechanism of the connector 3 to the unlocked state after a predetermined diagnosis process, and ends the charging flow.

  Next, the discharge operation (discharge flow) of the storage battery 41 in the power conversion system 10 of the present embodiment will be briefly described.

  After the connector 3 is connected to the connection port 42, the power conversion system 10 starts a discharge flow by performing a predetermined operation for starting discharge on an operation unit (not shown). A discharge start signal is transmitted to the vehicle 4. When receiving the discharge start signal, the electronic control unit of the electric vehicle 4 starts CAN communication with the power conversion system 10 and exchanges data such as the capacity of the storage battery 41.

  When the preparation for discharging is completed, the electronic control unit of the electric vehicle 4 transmits a discharge permission signal to the power conversion system 10. When receiving the discharge permission signal, the power conversion system 10 causes the drive current to flow from the power conversion device 1 to the connector 3 to drive the lock mechanism of the connector 3 to be in the locked state. Thereafter, the power conversion system 10 notifies the electronic control unit of the electric vehicle 4 that the discharge preparation is completed.

  When receiving the notification from the power conversion system 10, the electronic control unit of the electric vehicle 4 closes the second switch 43 and starts discharging the storage battery 41 to the power conversion system 10.

  When the capacity of the storage battery 41 reaches a specified value, the electronic control unit of the electric vehicle 4 transmits a stop request to the power conversion system 10. Thereafter, the electronic control unit of the electric vehicle 4 opens the second switch 43 when it is confirmed that the discharge current has decreased to a predetermined value or less. When the power conversion system 10 receives the stop request, the power conversion system 10 sets the lock mechanism of the connector 3 to the unlocked state after a predetermined diagnosis process, and ends the discharge flow.

  By the way, the power conversion system 10 of this embodiment is provided with the detection circuit 32 which detects the presence or absence of abnormality of the 2nd switch 43 of the electric vehicle 4 as shown in FIG. This detection circuit 32 has a measurement unit 321 that measures the voltage values of the measurement points P <b> 1 and P <b> 2 set in the power supply path 5 in the connector 3. Here, the measurement unit 321 is configured to measure the measurement points P <b> 1 and P <b> 2 set on the electric vehicle 4 side of the first switch 31 in the power supply path 5, that is, between the switch 31 and the contact part 33 in the first power supply path 51. Measure the voltage value. The measurement unit 321 is configured to measure the voltage values at the measurement points P1 and P2 with the second switch 43 opened.

  Therefore, the detection circuit 32 can measure the voltage applied from the electric vehicle 4 to the first power supply path 51 by the measurement unit 321 regardless of whether the first switch 31 is opened or closed. Therefore, even if the detection circuit 32 is in a state where the temperature of the contact portion 33 exceeds a predetermined temperature and the first switch 31 is in an open state, for example, the detection circuit 32 performs the second opening / closing based on the measurement result of the measurement portion 321. The presence / absence of abnormality of the vessel 43 can be detected.

  Further, in the power conversion system 10 of the present embodiment, the detection circuit 32 performs power conversion on a determination unit 322 that determines whether the second switch 43 is abnormal and a binary signal that represents the determination result of the determination unit 322. Each of the connectors 3 has a notification unit 323 that transmits to the device 1. The determination unit 322 compares the voltage value measured by the measurement unit 321 with a predetermined threshold, and if the voltage value (measurement value) measured by the measurement unit 321 exceeds the threshold, the second switch 43 is abnormal. It is configured to determine that there is.

  That is, even when the electronic control unit of the electric vehicle 4 opens the second switch 43, if the second switch 43 is not opened by welding, for example, the measurement points P1, P2 of the first power supply path 51 A voltage is applied from the storage battery 41 via the second switch 43. In short, the state in which the second switch 43 is opened here means a state in which an instruction signal for opening the second switch 43 is generated, and the second switch 43 is formed by welding or the like. This includes a state where the 43 contacts (the first contact 431 and the second contact 432) are not physically open. Therefore, even when the second switch 43 is opened, the contact of the second switch 43 is not actually opened due to an abnormality (for example, welding) of the second switch 43, and the measurement points P1 and P2 are not opened. There is a possibility that a voltage is applied from the storage battery 41 via the second switch 43.

  Therefore, the detection circuit 32 measures the voltage value of the measurement points P1 and P2 with the second switch 43 opened by the measurement unit 321. If the measurement value is equal to or less than the threshold value, the second switch 43 If the measured value exceeds the threshold, it is determined that the second switch 43 is abnormal. Further, the detection circuit 32 receives a determination result of the determination unit 322, and receives a signal composed of a binary value of a first value indicating “abnormal” and a second value indicating “abnormal” from the notification unit 323. It transmits to the power converter device 1.

  Specifically, as shown in FIG. 2, the measurement unit 321 includes a plurality (seven in this case) of constant current diodes D1 to D7, a photocoupler 3211, a photo MOS (metal-oxide-semiconductor) relay ( Photo mos relay (registered trademark) 3212. The plurality of constant current diodes D1 to D7, the primary side of the photocoupler 3211, and the secondary side of the photoMOS relay 3212 are connected in series between the measurement points P1 and P2 of the first power supply path 51. . The primary side of the photo MOS relay 3212 is connected to a control unit 324 described later. The secondary side of the photocoupler 3211 is connected to the determination unit 322.

  In this configuration, the measurement unit 321 receives the output of the control unit 324 and the photoMOS relay 3212 is turned on, the series current circuit of the constant current diodes D1 to D7 and the primary side of the photocoupler 3211 includes The voltages at the measurement points P1 and P2 are applied. Therefore, the measurement unit 321 determines whether the voltage at the measurement points P1 and P2 of the first power supply path 51 exceeds the forward voltage on the primary side of the constant current diodes D1 to D7 and the photocoupler 3211. The secondary side becomes conductive (ON).

  Therefore, the determination unit 322 compares the voltage value measured by the measurement unit 321 with the threshold value by monitoring the output of the photocoupler 3211 with the control unit 324 turning on the photo MOS relay 3212, and the second It is determined whether or not the switch 43 is abnormal. The notification unit 323 is connected to the communication line 23 of the cable 2, receives the determination result of the determination unit 322, and transmits a binary signal to the power conversion device 1.

  Here, the control unit 324 is configured to turn on the photo MOS relay 3212 in accordance with an instruction from the power conversion device 1 and cause the determination unit 322 to determine whether there is an abnormality in the second switch 43. In the present embodiment, the control unit 324 turns on the photo MOS relay 3212 using, as a trigger, the start of diagnostic processing immediately before the locking mechanism of the connector 3 shifts from the locked state to the unlocked state in the charging flow and discharging flow. .

  That is, when the power conversion system 10 receives a stop request from the electric vehicle 4 in the charge flow and the discharge flow, the lock mechanism of the connector 3 is unlocked after a predetermined diagnosis process. It is used as a trigger for determining the abnormality of the second switch 43. Thereby, the measurement part 321 measures the voltage value of the measurement points P1 and P2 in the state which opened the 2nd switch 43, and when the measurement value at that time exceeds the threshold value, the judgment part 322 Therefore, it is determined that the second switch 43 has an abnormality.

  However, the configuration of the measurement unit 321 illustrated in FIG. 2 is merely an example, and the measurement unit 321 is not limited to the specific circuit described above. In short, the measurement unit 321 has a function of measuring the voltage values of the measurement points P1 and P2 set on the electric vehicle 4 side from the first switch 31 in the power supply path 5 with the second switch 43 opened. The configuration can be appropriately changed within the range.

  The power conversion device 1 receives the detection result of the detection circuit 32, that is, the binary signal transmitted from the notification unit 323, and informs the notification unit 13 when the second switch 43 is abnormal. To notify. The alerting | reporting part 13 alert | reports by displaying the message to the effect that the 2nd switch 43 has abnormality on the display (not shown) of the power converter device 1, for example. Furthermore, when there is an abnormality in the second switch 43, the power conversion device 1 desirably keeps the lock mechanism in the locked state without shifting to the unlocked state, and displays that fact on the display. If there is no abnormality in the second switch 43, the power conversion device 1 shifts the lock mechanism to the unlocked state after the end of the diagnostic process.

  In the present embodiment, as described above, the measurement unit 321, the determination unit 322, the notification unit 323, and the control unit 324 that constitute the detection circuit 32 are all provided in the connector 3. The detection circuit 32 may have a function of displaying the detection result on an indicator lamp (not shown) provided in the connector 3.

  Since the power conversion system 10 of the present embodiment described above includes the detection circuit 32 that detects the presence or absence of an abnormality in the second switch 43 inserted in the power supply path 5 in the electric vehicle 4, Whether or not the second switch 43 provided in the vehicle 4 is abnormal can be detected. Therefore, according to this power conversion system 10, even if an abnormality such as welding occurs in the second switch 43 in the electric vehicle 4, appropriate measures can be taken immediately.

  Here, the detection circuit 32 measures the voltage values at the measurement points P <b> 1 and P <b> 2 set on the electric vehicle 4 side with respect to the first switch 31 in the power supply path 5 with the second switch 43 opened. The connector 3 has a measuring unit 321 and detects the presence or absence of an abnormality based on the measurement result of the measuring unit 321. Therefore, even if the detection circuit 32 is in a state where, for example, the temperature of the contact portion 33 exceeds a predetermined temperature and the first switch 31 is opened, the second opening / closing is performed based on the measurement result of the measurement portion 321. The presence / absence of abnormality of the vessel 43 can be detected.

  Furthermore, the detection circuit 32 compares the voltage value measured by the measurement unit 321 with a predetermined threshold as in the present embodiment, and if the voltage value exceeds the threshold, the second switch 43 is abnormal. It is preferable to have a determination unit 322 that determines that As a result, the detection circuit 32 can determine whether the second switch 43 is abnormal by a simple process of simply comparing the voltage value measured by the measurement unit 321 with the threshold value.

  Moreover, the detection circuit 32 may include the determination unit 322 and the notification unit 323 that transmits a binary signal representing the determination result of the determination unit 322 to the power conversion device 1 in the connector 3 as in the present embodiment. preferable. That is, the detection circuit 32 performs the determination in the connector 3 until it is determined whether there is an abnormality in the second switch 43, and only transmits a binary signal representing the determination result to the power conversion device 1. Therefore, the detection circuit 32 can suppress the amount of data transmitted to the power conversion device 1 to be smaller than that in the case where the measurement value of the measurement unit 321 is transmitted to the power conversion device 1, and is less susceptible to noise.

  Note that at least the measurement unit 321 may be provided in the connector 3, and the detection circuit 32 may be provided in a distributed manner in the connector 3 and the power conversion device 1. For example, the determination unit 322 may be provided in the power conversion device 1 as a modification of the present embodiment. In this case, the notification unit 323 transmits the measurement result of the measurement unit 321 to the power conversion device 1, and the determination unit 322 determines whether there is an abnormality based on the measurement result transmitted from the notification unit 323. As another modification, the notification unit 323 may be omitted. In this case, the detection circuit 32 displays, for example, the detection result on the indicator lamp of the connector 3.

(Embodiment 2)
In the power conversion system 10 of the present embodiment, the detection circuit 32 includes a discharge unit that discharges the charge accumulated in the capacitive component on the power conversion device 1 side from the second switch (vehicle switch) 43 in the power supply path 5. The connector 3 is different from the power conversion system 10 according to the first embodiment. Hereinafter, the same configurations as those of the first embodiment are denoted by common reference numerals, and description thereof will be omitted as appropriate.

  For example, in the electric vehicle 4, since the second power supply path 52 between the second switch 43 and the connection port 42 has a line capacitance (for example, 1 μF or less), the line capacitance is used as a capacitance component by the measuring unit 321. May affect the measured value. In this case, even if the second switch 43 is normally switched from the closed state to the open state, there is a possibility that the measurement value of the measurement unit 321 does not immediately fall below the threshold due to the influence of the capacitance component. In the power conversion system 10 of the present embodiment, in order to avoid such an influence of the capacitive component, the detection circuit 32 includes a discharge unit for discharging the charge accumulated in the capacitive component in the connector 3.

  Furthermore, in the present embodiment, in the detection circuit 32, the measurement unit 321 is also used as the discharge unit. That is, the detection circuit 32 suppresses an increase in the number of parts by sharing the measurement unit 321 and the discharge unit, instead of providing the discharge unit separately from the measurement unit 321. Specifically, the detection circuit 32 employs the measurement unit 321 having the configuration shown in FIG. 2, and when the photo MOS relay 3212 is turned on, a series circuit of the constant current diodes D1 to D7 and the primary side of the photocoupler 3211 is used. By flowing a current, the charge accumulated in the capacitive component is discharged.

  Therefore, the detection circuit 32 measures the voltage value of the measurement points P1 and P2 with the measurement unit 321 after a predetermined delay time has elapsed since the photo MOS relay 3212 is turned on, and the second switch 43 based on the measurement value. It is configured to detect whether there is an abnormality. That is, the detection circuit 32 discharges the electric charge accumulated in the capacitive component by the measurement unit 321 as a discharge unit, and then compares the measurement value of the measurement unit 321 with the threshold value in the determination unit 322. The presence or absence of abnormality 43 is judged.

  Next, operation | movement of the power conversion system 10 of this embodiment is demonstrated with reference to FIG. 3A shows the open / close state of the second switch 43, FIG. 3B shows the on / off state of the photoMOS relay 3212, and FIG. 3C shows the voltages at the measurement points P1 and P2.

  That is, when the second switch 43 is changed from the closed state to the open state (t1), the voltages at the measurement points P1 and P2 begin to gradually decrease due to the influence of the capacitance component. Thereafter, the control unit 324 turns on the photoMOS relay 3212 using the start of the diagnostic process immediately before the locking mechanism of the connector 3 shifts from the locked state to the unlocked state (t2). Thereby, the measurement part 321 functions as a discharge part, and the voltage of measurement point P1, P2 falls rapidly. Then, when the delay time elapses, the determination unit 322 reads the measurement value of the measurement unit 321 at that time (t3) and compares it with a threshold value to determine whether the second switch 43 is abnormal.

  According to the power conversion system 10 of the present embodiment described above, the detection circuit 32 includes the discharge unit that discharges the charge accumulated in the capacitive component on the power conversion device 1 side from the second switch 43 in the power supply path 5. Since the connector 3 is provided, it is possible to avoid erroneous detection due to the influence of the capacitance component.

  Furthermore, as in the present embodiment, it is desirable that the measurement unit 321 is also used as a discharge unit. As a result, the circuit configuration is simplified as compared with the case where the discharge unit is provided separately from the measurement unit 321.

  Other configurations and functions are the same as those of the first embodiment.

  Note that the discharge unit may be provided separately from the measurement unit 321. Further, the configuration described in this embodiment can be appropriately combined with the modification of the first embodiment.

(Embodiment 3)
As shown in FIG. 4, the power conversion system 10 according to the present embodiment is different from the power conversion system 10 according to the first embodiment in that the protective device inserted in the power supply path 5 in the connector 3 includes a fuse 36. Hereinafter, the same configurations as those of the first embodiment are denoted by common reference numerals, and description thereof will be omitted as appropriate.

  The fuse 36 as a protection device is inserted on the high potential side of the first power supply path 51 formed between the cable 2 and the contact portion 33 of the connector 3. The fuse 36 may be inserted on the low potential side of the first power supply path 51.

  Here, as an example, the fuse 36 uses a current (for example, 40 A) that is twice the maximum current (for example, 20 A) that flows through the first power supply path 51 in a normal state as the rated current. The rated current is a current that defines the fusing characteristics of the fuse element (fusible body), and is a current that does not blow the fuse element even if it flows through the fuse 36. In general, the fuse 36 has a fusing characteristic that is determined by using the rated current such that, for example, a current of 135% of the rated current causes the fuse element to blow within 60 minutes.

  Further, the fuse 36 is a current limiting fuse. In this case, the current-limiting fuse is filled with an arc-extinguishing agent around the fuse element in the container (tube), and after the fuse element is blown, a relatively high arc voltage is generated to limit the increase in overcurrent. It is a fuse. Note that the protection device in the present embodiment only needs to include at least one fuse 36, and may include a plurality of fuses connected in series.

  The connector 3 includes such a fuse 36, so that when an abnormal current such as an overcurrent or a short circuit current flows through the first power supply path 51, the fuse element of the fuse 36 is blown, and the fuse 36 generates an abnormal current. Can be blocked.

  Here, the detection circuit 32 includes a measurement unit 321 that measures the voltage values of the measurement points P1 and P2 set on the electric vehicle 4 side from the fuse 36 in the power supply path 5 with the second switch 43 opened. The connector 3 has an abnormality based on the measurement result of the measurement unit 321.

  According to the power conversion system 10 of the present embodiment described above, the detection circuit 32 has the second switch 43 based on the measurement result of the measurement unit 321 even when the fuse 36 serving as the protection device is blown. The presence or absence of abnormalities can be detected. That is, although the power conversion system 10 of the present embodiment uses the fuse 36 as a protection device, the configuration and technology using the switch as the protection device in that the presence or absence of an abnormality in the second switch 43 can be detected. The same. Therefore, according to this power conversion system 10, even if an abnormality such as welding occurs in the second switch 43 in the electric vehicle 4, appropriate measures can be taken immediately.

  Other configurations and functions are the same as those of the first embodiment.

  In the example of FIG. 4, the power conversion system 10 includes the fuse 36 as a protection device instead of the first switch 31 (see FIG. 1), but is not limited to this example, and the fuse 36 and the switch May be used as a protective device. In addition, the configuration described in this embodiment can be appropriately combined with the modification described in Embodiment 1 or the configuration described in Embodiment 2.

  The above-described embodiment is an example of the present invention. For this reason, the present invention is not limited to the above-described embodiment, and various modifications can be made depending on the design and the like as long as the technical idea according to the present invention is not deviated from this embodiment. Of course, it is possible to change.

DESCRIPTION OF SYMBOLS 1 Power converter device 3 Connector 31 1st switch (protection device)
32 Detection Circuit 321 Measurement Unit (Discharge Unit)
322 Judgment unit 323 Notification unit 36 Fuse (protection device)
4 Electric Vehicle 41 Storage Battery 43 Second Switch (Vehicle Switch)
5 Power supply path 10 Power conversion system P1, P2 Measurement points

Claims (6)

A power conversion path and a power supply path between the power conversion apparatus and the storage battery by being detachably attached to a connection port of an electric vehicle mounted with the storage battery and connected to the power conversion apparatus via a cable And a connector for forming
A protective device comprising at least one of a switch and a fuse and inserted into the power supply path in the connector;
A detection circuit for detecting the presence or absence of abnormality of a vehicle switch inserted in the power supply path in the electric vehicle,
The detection circuit has a measurement unit in the connector for measuring a voltage value at a measurement point set on the electric vehicle side from the protection device in the power supply path in a state where the vehicle switch is opened. It is comprised so that the presence or absence of the said abnormality may be detected based on the measurement result of a part. The power conversion system characterized by the above-mentioned. The detection circuit includes a determination unit that compares the voltage value measured by the measurement unit with a predetermined threshold value and determines that the vehicle switch has an abnormality when the voltage value exceeds the threshold value. The power conversion system according to claim 1, wherein the system is a power conversion system. 3. The power according to claim 2, wherein the detection circuit includes the determination unit and a notification unit that transmits a binary signal representing a determination result of the determination unit to the power conversion device. Conversion system. The said detection circuit has the discharge part which discharges the electric charge accumulate | stored in the capacity | capacitance component by the side of the said power converter from the said vehicle switch in the said electric power feeding path in the said connector. The any one of Claims 1-3 characterized by the above-mentioned. The power conversion system according to item 1. The power conversion system according to claim 4, wherein the measurement unit is also used as the discharge unit.   The connector used for the power conversion system of any one of Claims 1-5.

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