JP2017079496A - Contactor failure determining device and contactor failure determining method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve accuracy in determining a failure of a contactor.SOLUTION: A contactor failure determining device 10 is configured to determine a failure of a contactor group which includes: a positive electrode-side contactor 30 provided on a positive electrode-side power source line L1 connecting a positive electrode of a battery 22, which supplies power to a driving motor 24 for a vehicle, to a positive electrode of the driving motor 24; a negative electrode-side contactor 32 provided on a negative electrode-side power source line L2 connecting a negative electrode of the battery 22 to a negative electrode of the driving motor 24; and a precharge contactor 34 connected in parallel with the positive electrode-side contactor 30 or to the negative electrode-side contactor 32. An ammeter 28 detects electric currents flowing into the positive electrode-side power source line L1 closer to the battery 22 than the positive electrode-side contactor 30. A failure determining portion 102 sequentially opens and closes the contactor group, and determines whether or not a failure occurs in any contactor of the contactor group on the basis of change in electric currents caused by the opening and closing.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a contactor failure determination device and a contactor failure determination method for determining whether or not a contactor group provided in a power supply line from a battery has a failure.

Conventionally, a contactor (positive electrode side contactor) that connects / disconnects an electrical connection to a power supply line between a battery mounted as a driving power source of a vehicle such as an electric vehicle or a hybrid vehicle and a load device (for example, a driving motor). And a negative electrode side contactor).
Further, since the driving power source of the vehicle has a high voltage, a precharge contactor is provided in parallel with the positive electrode side contactor to suppress an inrush current when the high voltage power source is activated (when the high voltage circuit is connected).

  The above contactor group is a safety mechanism of the power supply circuit, and it is necessary to periodically check whether these contactors operate normally. For this reason, in general, the contactor is opened and closed when the vehicle is started (when the high voltage circuit is connected) and when the vehicle is terminated (when the high voltage circuit is disconnected) to determine whether or not the contactor has failed. .

For example, in Patent Document 1 below, welding abnormality of the negative electrode contactor is diagnosed at the timing of outputting a start time command for starting the vehicle to the positive electrode contactor, the negative electrode contactor, and the precharge contactor, and the stop for stopping the vehicle is performed. A technique for diagnosing a welding abnormality of a positive contactor and a precharge contactor at a timing of outputting a time command is disclosed.
In Patent Document 1, each contactor is sequentially opened and closed, and the voltage of a capacitor (smoothing capacitor) provided in the inverter of the drive motor is detected to determine whether or not the contactor is welded.

Further, for example, in Patent Document 2 below, when it is determined that the battery is not charged / discharged not only at the time of starting or ending the vehicle but also during traveling, contactor failure determination is performed, and contactor failure detection frequency is determined. Is increasing so that welding can be detected earlier.
That is, in Patent Document 2 below, when the vehicle speed is approximately zero and the brake pedal is depressed, it is determined that the battery is not being charged / discharged, and the switching element of the inverter is switched and stored in the capacitor. The generated charge is discharged. After the discharge, the relays (positive contactor and negative contactor) are turned off to detect voltages RV1 and RV2 between the terminals of the relay, and one of the voltages RV1 and RV2 is equal to or less than a threshold value RVref (approximately 0). It is determined whether or not. When the value is equal to or less than the threshold value RVref, it is determined that the relay is welded and the LED is turned on.

JP2013-169087A JP 2002-175750 A

As described above, the contactor failure determination is generally performed when the high voltage circuit is connected or disconnected, that is, at the timing when the vehicle start switch is turned on / off.
Here, in general, the operation of the start switch is performed in a state where the vehicle is stopped. However, if the user operates the start switch accidentally or intentionally while the vehicle is traveling, the operation is interlocked with the operation. Thus, the contactor failure determination is performed even during traveling.
When the vehicle drive motor is a direct drive motor whose output shaft is directly connected to the axle, the voltage of the capacitor fluctuates due to the induced voltage of the drive motor while the vehicle is running (when the axle is rotating).
Therefore, when contactor failure determination is performed while running on a vehicle equipped with a direct drive motor, an increase in the capacitor voltage is detected even if the contactor has not failed (welding), and failure determination cannot be performed correctly. There is a problem.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a contactor failure determination device and a contactor failure determination method capable of improving contactor failure determination accuracy.

In order to achieve the above-mentioned object, a contactor failure determination device according to claim 1 is a positive electrode provided on a positive power line connecting a positive electrode of a battery that supplies power to a load device and a positive electrode of the load device. A contactor failure determination device for determining a failure of a contactor group including a side contactor, and a negative electrode side contactor provided on a negative electrode side power line connecting a negative electrode of the battery and a negative electrode of the load device, wherein the positive electrode Sequentially opening and closing the contactor group, a current detection unit for detecting a current flowing in the positive side power line on the battery side from the side contactor, or the negative side power line on the battery side from the negative side contactor, A failure determination unit that determines whether or not a failure has occurred in any of the contactor groups based on a change in the current accompanying opening and closing. And wherein the Rukoto.
In the contactor failure determination apparatus according to the invention of claim 2, the failure determination unit performs the determination when a predetermined failure determination trigger occurs, and the failure determination trigger opens the contactor group and opens the load An instruction for instructing a transition from a state in which the connection between the device and the secondary battery is disconnected to a state in which the positive electrode side contactor and the negative electrode side contactor are closed to connect the load device and the secondary battery. And when the instruction is input, the contactor failure determination unit determines that no failure has occurred in the contactor group, and then closes the positive electrode side contactor and the negative electrode side contactor and A battery connection part for connecting the secondary battery is further provided.
In the contactor failure determination device according to a third aspect of the invention, the load device is a drive motor for driving a vehicle, the battery is a drive battery for the vehicle, and the drive motor rotates an output shaft. It is a direct drive motor that transmits directly to the axle of the vehicle.
The contactor failure determination device according to the invention of claim 4 further comprises notification means for notifying a user when it is determined by the contactor failure determination section that a failure has occurred in any of the contactor groups. Features.
According to a fifth aspect of the present invention, there is provided a contactor failure determination method comprising: a positive contactor provided on a positive power line connecting a positive electrode of a battery supplying power to a load device and a positive electrode of the load device; and a negative electrode of the battery A contactor failure determination method for determining failure of a contactor group including a negative electrode side contactor provided on a negative electrode side power supply line connecting the negative electrode of the load device and a contactor opening / closing step of sequentially opening and closing the contactor group A current detection step for detecting a current flowing through the positive power line on the battery side from the positive contactor or the negative power line at the battery side from the negative contactor; and opening and closing of the contactor group A failure that determines whether or not a failure has occurred in any of the contactor groups based on the change in the current accompanying the Characterized in that it includes a constant step.

According to the first and fifth aspects of the invention, when determining the failure of the contactor group connecting the load device and the battery, the failure is determined using the change in the current flowing from the contactor to the battery side. This is advantageous in avoiding erroneous determination as a contactor failure when an induced voltage is generated on the load device side, improving the determination accuracy of failure determination, and improving the reliability of the power supply circuit. Become.
According to the invention of claim 2, when there is an instruction to connect the load device to the battery, the load device and the battery are connected after confirming that no failure has occurred in the contactor group. This is advantageous for reliably connecting and disconnecting the load device and the battery.
According to the invention of claim 3, even when the drive motor is a direct drive motor and the capacitor voltage is increased by the induced voltage of the drive motor due to the rotation of the axle, avoid erroneous determination as a contactor failure. This is advantageous in improving the determination accuracy of the failure determination and improving the reliability of the vehicle system.
According to the invention of claim 4, when it is determined that a failure has occurred in any of the contactor groups, the user is notified. Thereby, the user can recognize that the vehicle is in a state different from the normal state, which is advantageous in quickly performing the necessary response.

It is explanatory drawing which shows the structure of the high voltage circuit by which the contactor failure determination apparatus 10 was mounted. It is a flowchart which shows the procedure of the failure determination process by the contactor failure determination apparatus. It is explanatory drawing which shows typically the failure determination by the failure determination part 102. FIG.

Exemplary embodiments of a contactor failure determination device and a contactor failure determination method according to the present invention will be explained below in detail with reference to the accompanying drawings.
In the present embodiment, it is assumed that the vehicle is an electric vehicle (electric vehicle) that travels by driving a driving motor with electric power.
(Embodiment)
<Configuration of Contactor Failure Determination Device 10>
FIG. 1 is an explanatory diagram showing a configuration of a high voltage circuit on which the contactor failure determination device 10 is mounted.
The contactor failure determination device 10 according to the embodiment is mounted on a high voltage circuit 20 including a vehicle driving power supply (battery 22). The contactor failure determination device 10 is realized by performing failure determination processing, which will be described later, by an ECU (Electronic Control Unit) 12 of the vehicle.

The battery 22 is mounted as a driving power source for the driving motor 24 that is a load device in the vehicle, and supplies power to the driving motor 24.
The battery 22 is an assembled battery in which a plurality of battery cells are connected in series, and a driving motor 24 (more specifically, a driving motor) supplies power to the positive power line L1 connected to the positive electrode of the battery 22. The negative electrode of the drive motor 24 (motor inverter 26) is connected to the positive electrode of the motor inverter 26) that supplies an alternating current to the motor 24, and the negative electrode power line L2 connected to the negative electrode.
The battery 22 is a high-voltage power supply, and in this embodiment, the battery voltage Vb is assumed to be 300V, for example.

The drive motor 24 is driven by electric power supplied from the battery 22 and rotates the axle of the vehicle.
More specifically, a motor inverter 26 that converts a direct current supplied from the battery 22 into an alternating current is provided between the drive motor 24 and the battery 22. The drive motor 24 includes a motor inverter 26. The current converted into alternating current is supplied.
In the present embodiment, it is assumed that the drive motor 24 is a direct drive motor whose output shaft is directly connected to the axle of the vehicle.
For this reason, even when the user travels downhill or the like without operating the accelerator pedal or the brake pedal, an induced voltage is generated in the drive motor 24 due to the rotation of the axle, The voltage Vc of the capacitor 264 will increase.

The motor inverter 26 includes a switching circuit 262 and a capacitor 264.
The switching circuit 262 converts the direct current supplied from the battery 22 into an alternating current by switching. The switching circuit 262 is controlled according to a required output to the drive motor 24 by an MCU (Motor Control Unit) (not shown).
Both ends of the capacitor 264 are connected to the positive power supply line L1 and the negative power supply line L2 on the battery 22 side from the switching circuit 262, and smooth the voltage fluctuation generated by the switching in the switching circuit 262.
In addition, the motor inverter 26 is provided with a discharge resistor or the like for discharging the charge stored in the capacitor 264 when the high-voltage circuit 20 of the vehicle is disconnected.

A contactor group including a positive contactor 30, a negative contactor 32, and a precharge contactor 34 is provided on the power supply lines L1 and L2 between the battery 22 and the motor inverter 26.
More specifically, the positive electrode side contactor 30 is provided on the positive electrode side power supply line L 1 connecting the positive electrode of the battery 22 and the positive electrode of the driving motor 24, and the negative electrode side contactor 32 is provided on the negative electrode of the battery 22 and the driving motor 24. The precharge contactor 34 is provided in parallel with the positive electrode side contactor 30 on the positive electrode side power supply line L1.
In the present embodiment, the precharge contactor 34 is provided in parallel with the positive electrode side contactor 30, but the precharge contactor 34 may be provided in parallel with the negative electrode side contactor 32.

The positive electrode side contactor 30 and the negative electrode side contactor 32 are provided to connect and disconnect the electrical connection between the drive motor 24 and the battery 22 in the high voltage circuit 20. In the following description, the connection state of the high voltage circuit 20 means a state in which both the positive contactor 30 and the negative contactor 32 are closed and the drive motor 24 and the battery 22 are electrically connected.
The precharge contactor 34 is a contactor that is closed before closing the positive electrode side contactor 30 in order to prevent an inrush current from flowing through the capacitor 264 when the high voltage circuit 20 is connected (starting up).
More specifically, a precharge resistor 36 is connected in series to the precharge contactor 34. When the precharge contactor 34 and the negative contactor 32 are closed, the current flowing on the circuit is limited.
When the high voltage circuit 20 is connected, first, the precharge contactor 34 and the negative contactor 32 are closed, and the voltage of the capacitor 264 is made equal to the battery voltage by the limited current (precharge). Thereafter, the positive electrode side contactor 30 is closed and the precharge contactor 34 is opened to complete the connection of the high voltage circuit 20.

The contactor failure determination device 10 described above determines whether or not there is a failure in the contactor group including the positive contactor 30, the negative contactor 32, and the precharge contactor 34.
In the present embodiment, welding (closed sticking maintained in a closed state) will be mainly described as a contactor failure form. However, contactor failure forms include, for example, open sticking maintained in an open state, Also included are control failures (the state is not switched because the control signal is not transmitted but the control signal is not transmitted).

Further, an ammeter 28 is provided on the positive power supply line L <b> 1 of the battery 22 rather than the positive contactor 30. The ammeter 28 detects the current Ib flowing through the positive power supply line L1 and outputs it to the ECU 12. The ammeter 28 corresponds to the current detector in the claims.
The ammeter 28 may be provided in the negative power supply line L2 of the battery 22 rather than the negative contactor 32.

The ECU 12 is a control unit that controls the entire vehicle, and includes a CPU, a ROM that stores and stores a control program, a RAM as an operation area of the control program, an EEPROM that holds various data in a rewritable manner, peripheral circuits, and the like. It is configured to include an interface unit that takes an interface.
In the present embodiment, the ECU 12 is described as realizing the contactor failure determination device 10, but other control units mounted on the vehicle, for example, a BMU (Battery Management Unit) for controlling the battery 22 or the above-described MCU. The contactor failure determination device 10 may be realized.

The ECU 12 is connected to the start switch 40 and the notification unit 42.
The activation switch 40 is provided in the driver's seat and accepts vehicle activation and termination operations.
The notification unit 42 notifies the user when it is determined by the failure determination unit 102 described later that a failure has occurred in any of the contactor groups.
As the notification unit 42, various conventionally known notification devices such as a display, an indicator lamp, and a speaker can be used.

  The ECU 12, the start switch 40, and the notification unit 42 are driven by electric power stored in an auxiliary battery (not shown) provided separately from the battery 22. The auxiliary battery is provided to drive various auxiliary machines in the vehicle, and is a battery having a lower voltage (for example, 12 V) than the battery 22. That is, the contactor failure determination device 10 is driven using a power supply system different from the high-voltage power supply system that receives power supply from the battery 22.

The ECU 12 implements the failure determination unit 102 and the battery connection unit 104 when the CPU executes the control program.
Failure determination unit 102 sequentially opens and closes the contactor group (positive contactor 30, negative contactor 32, and precharge contactor 34), and based on the change in current (detection current Ib of ammeter 28) associated with the opening and closing. It is determined whether or not a failure has occurred in any of the above.
In the present embodiment, failure determination unit 102 determines whether or not there is a failure when a predetermined failure determination trigger occurs. The failure determination trigger is, for example, an on operation or an off operation of the start switch 40, that is, an operation of switching connection / disconnection of the high voltage circuit 20 including the battery 22 and the drive motor 24 (including the motor inverter 26). .
In the present embodiment, the on-operation of the start switch 40 is a failure determination trigger. When the start switch 40 is turned on, the contactor group is controlled to be opened and the drive motor and the battery 22 are disconnected (the high voltage circuit 20 is not connected) from the positive contactor 30 and the negative contact side. This is an instruction input for instructing switching to a state in which the contactor 32 is closed to connect the drive motor and the battery 22 (connection state of the high voltage circuit 20).
The timing at which the failure determination unit 102 performs the failure determination is not limited to this, and any timing may be used as long as the failure determination can be performed accurately.

As a failure determination method of the failure determination unit 102, for example, in the initial state, all contactor groups are controlled to be opened, and one of the positive contactor 30, the negative contactor 32, and the precharge contactor 34 is closed. By sequentially performing the above, it is possible to determine whether or not the contactor group is welded.
In this case, when all the contactor groups are opened, the connection between the battery 22 and the drive motor 24 (motor inverter 26) is disconnected, so that the current Ib in the initial state becomes zero. If the current Ib does not become zero at this time, it is considered that welding has occurred in both the positive electrode side and the negative electrode side contactor.
When only the positive electrode side contactor 30 is controlled to be closed from the initial state, only the contactor of one of the poles is in a closed state, and thus the current Ib normally remains zero. On the other hand, when the current Ib increases, it is considered that the positive and negative contactors are closed, and it can be determined that the negative electrode side contactor 32 is welded.
Similarly, if the current Ib increases when only the negative electrode side contactor 32 is controlled to be closed from the initial state, it can be determined that welding has occurred in the positive electrode side contactor 30 or the precharge contactor 34.
At this time, for example, it may be determined whether the positive contactor 30 or the precharge contactor 34 is welded based on the current value of the current Ib. That is, since the precharge resistor 36 is connected to the precharge contactor 34, the current Ib flowing through the circuit is limited, and the current value Ib is smaller when the precharge contactor 34 is welded than when the positive contactor 30 is welded. . Using this, it is possible to determine which contactor on the positive electrode side is welded.

Here, in this embodiment, the failure determination trigger is an ON operation of the start switch 40, but in general, an ON operation (and an OFF operation) of the start switch 40 is performed in a state where the vehicle is stopped. On the other hand, the user may accidentally or intentionally perform an ON operation (or OFF operation) of the start switch 40, that is, a connection operation or a disconnection operation of the high voltage circuit 20 while the vehicle is traveling. During the running, contactor failure determination is performed.
When the drive motor 24 is a direct drive motor as in the present embodiment, the capacitor voltage Vc varies with the induced voltage of the drive motor 24 while the vehicle is traveling (when the axle is rotating).
When the contactor failure is determined using the voltage Vc of the capacitor 264 as in the prior art in a state where such an induced voltage is generated, the voltage Vc of the capacitor 264 is obtained even when the contactor has not failed (welded). Is detected, and it is erroneously determined that the contactor has failed.

On the other hand, when the failure determination is performed using the current Ib as in the failure determination unit 102, the current Ib is generated due to the failure of the contactor group except when the capacitor voltage Vc is equal to the battery voltage Vb. A failure can be determined.
More specifically, the current Ib increases as the difference between the capacitor voltage Vc and the battery voltage Vb increases, and decreases as the capacitor voltage Vc approaches the battery voltage Vb. Further, when the capacitor voltage Vc is equal to the battery voltage Vb, the current Ib does not flow.
If there is even a slight difference between the capacitor voltage Vc and the battery voltage Vb, the current Ib flows. Therefore, by performing the failure determination using the current Ib, the accuracy of the failure determination can be improved.

The battery connection unit 104 controls the positive-side contactor 30 and the negative-side contactor 32 to be closed from the ON operation of the start switch 40, that is, the state where the connection of the high voltage circuit 20 is disconnected, and the drive motor 24 and the battery 22. When there is an instruction input for instructing switching to the connected state, the positive side contactor 30 and the negative side contactor 32 are closed to connect the driving motor 24 and the battery 22.
When the drive motor 24 and the battery 22 are actually connected, first, the precharge contactor 34 and the negative contactor 32 are closed and the capacitor voltage Vc is made equal to the battery voltage by the limited current (pre-charge). Charge), and then the positive contactor 30 is closed and the precharge contactor 34 is opened, and the drive motor 24 and the battery 22 are connected.

Here, after the failure determination unit 102 determines that no failure has occurred in the contactor group, the battery connection unit 104 closes the positive contactor 30 and the negative contactor 32 to connect the drive motor 24 and the battery 22 together. Connect.
That is, the battery connection unit 104 connects the driving motor 24 and the battery 22 only when the failure determination unit 102 determines that no failure has occurred in the contactor group, and the failure determination unit 102 causes the contactor group to have a failure. If it is determined that this occurs, the drive motor 24 and the battery 22 are not connected.
This avoids connecting the high voltage circuit 20 in a state where the contactor is out of order, for example, the positive electrode side and the negative electrode side contactor are welded on both sides, and the high voltage circuit 20 remains in the connected state. Problems such as overdischarge can be avoided.

FIG. 2 is a flowchart illustrating a procedure of failure determination processing by the contactor failure determination device 10.
First, the contactor failure determination device 10 determines whether or not the high voltage circuit 20 is in a connected state, that is, whether the positive contactor 30 and the negative contactor 32 are closed and the drive motor and the battery 22 are connected ( Step S200).
When the high voltage circuit 20 is in the connected state (step S200: Yes), the contactor failure determination device 10 continues the connection of the high voltage circuit 20 as it is until the start switch 40 is operated (end operation) (step S202). ).

On the other hand, when the high voltage circuit 20 is in a disconnected state, that is, when the positive contactor 30 and the negative contactor 32 are opened and the drive motor and the battery 22 are not connected (step S200: No), the contactor. The failure determination apparatus 10 waits until the start switch 40 is operated (start operation) (step S204: No loop).
When the activation switch 40 is operated (activation operation) (step S204: Yes), the failure determination unit 102 performs failure determination (step S206).

FIG. 3 is an explanatory diagram schematically showing failure determination by the failure determination unit 102. FIG. 3A shows a case where no failure occurs in any of the contactors, and FIG. 3B shows a case where a failure occurs in the positive contactor 30. Is shown.
First, FIG. 3A will be described. In FIG. 3A, since no failure has occurred in any of the contactors, and the actual open / close state of the contactor is in accordance with the control signal from the ECU 12, the actual open / close state of the contactor and the control signal from the ECU 12 are distinguished. Shown without.
In the initial state T <b> 0, the positive electrode side contactor 30, the negative electrode side contactor 32, and the precharge contactor 34 are all open, and power is not supplied from the battery 22 to the drive motor 24.
Thus, when all the contactors are open, the normal capacitor voltage Vc is 0V. However, when the axle is rotating, for example, when the vehicle is traveling on a downhill coast, the induced voltage of the drive motor 24 becomes higher than 0V as shown in FIG. When the failure determination is performed using the capacitor voltage Vc as in the prior art, there is a possibility that the failure is erroneously determined due to such an increase in the capacitor voltage Vc.
On the other hand, the current Ib used for failure determination by the failure determination unit 102 is 0 A from the initial state T0, and remains 0 A even when, for example, only the negative contactor is closed at time T1. As described above, by using the current Ib for contactor failure determination, it is possible to avoid erroneous determination of failure due to the increase in the capacitor voltage Vc.

Next, FIG. 3B will be described. In FIG. 3B, failure (welding) has occurred in the positive electrode side contactor 30, and the positive electrode side contactor 30 is in a closed state contrary to the control signal from the ECU 12 indicated by the dotted line.
In this case, the current Ib used for failure determination by the failure determination unit 102 is 0 A from the initial state T0 to time T1, but when the negative contactor is closed at time T1, a closed circuit is formed between the battery 22 and the load device. And a current Ib that is inversely proportional to the capacitor voltage Vc flows. As a result, the failure determination unit 102 can detect that a failure has occurred in the contactor (the positive contactor 30 or the precharge contactor 34) on the positive power supply line L1.
Note that the current Ib becomes 0 A when the capacitor voltage Vc becomes substantially equal to the battery voltage Vb at time T2 (charging of the capacitor is completed), for example. More specifically, when the induced voltage of the driving motor 24 is lower than the battery voltage, Ib = 0 as shown in FIG. 3B. Further, when the vehicle speed is high and the induced voltage of the driving motor 24 is higher than the battery voltage, Ib <0 (direction in which the battery 22 is charged). The capacitor voltage Vc is not completely the same as the battery voltage Vb because there is a difference in voltage drop due to the harness resistance between the motor inverter 26 and the battery 22.

Returning to the description of FIG. 2, when there is no failure in any of the contactors (step S <b> 208: Yes), the battery connection unit 104 controls the positive side contactor 30 and the negative side contactor 32 to be closed to drive the drive motor 24. And the battery 22 are connected, the high voltage circuit 20 is connected (step S210), and the processing according to this flowchart ends.
On the other hand, if any of the contactors has a failure (step S208: No), the battery connection unit 104 does not connect the high voltage circuit 20 (connection prohibition of the high voltage circuit 20), and the notification unit 42 sets the contactor group. That a failure has occurred in either of them (step S212), and the processing according to this flowchart is terminated.

As described above, according to the contactor failure determination device 10 according to the embodiment, when determining a failure of the contactor group connecting the load device and the battery 22, the change in the current flowing from the contactor group to the battery 22 side. Is used to determine the failure.
This is advantageous in avoiding erroneous determination as a contactor failure when an induced voltage is generated on the load device side, improving the determination accuracy of failure determination, and improving the reliability of the power supply circuit. Become.
Further, according to the contactor failure determination device 10, when there is a connection instruction between the load device and the battery 22, the load device and the battery 22 are connected after confirming that no failure has occurred in the contactor group. This is advantageous in reliably connecting and disconnecting the load device and the battery 22.
Further, according to the contactor failure determination device 10, the drive motor 24 that is a load device is a direct drive motor, and even when the capacitor voltage Vc is increased by the induced voltage of the drive motor 24 due to the rotation of the axle, This is advantageous in avoiding erroneous determination as a failure, improving the determination accuracy of the failure determination, and improving the reliability of the vehicle system.
Moreover, according to the contactor failure determination apparatus 10, when it is determined that a failure has occurred in any of the contactor groups, the user is notified. Thereby, the user can recognize that the vehicle is in a state different from the normal state, which is advantageous in quickly performing the necessary response.

  DESCRIPTION OF SYMBOLS 10 ... Contactor failure determination apparatus, 102 ... Failure determination part, 104 ... Battery connection part, 20 ... High voltage circuit, 22 ... Battery, 24 ... Motor for drive, 26 ... Motor inverter, 262 ... Switching circuit, 264 ... capacitor, 28 ... ammeter, 30 ... positive contactor, 32 ... negative contactor, 34 ... precharge contactor, 36 ... precharge resistor, 40 ... start switch, 42 ... ... notification part, L1 ... positive electrode side power line, L2 ... negative electrode side power line.

Claims (5)

A positive-side contactor provided on a positive-side power supply line that connects a positive electrode of a battery that supplies power to a load device and a positive electrode of the load device, and a negative-side power supply line that connects a negative electrode of the battery and a negative electrode of the load device A contactor failure determination device for determining a failure of a contactor group including a negative electrode side contactor provided on the top;
A current detection unit for detecting a current flowing in the positive power line on the battery side from the positive contactor or the negative power line on the battery side than the negative contactor;
A failure determination unit that sequentially opens and closes the contactor group and determines whether or not a failure has occurred in any of the contactor groups based on a change in the current associated with the opening and closing;
A contactor failure determination device comprising: The failure determination unit performs the determination when a predetermined failure determination trigger occurs,
The failure determination trigger is configured to close the positive electrode side contactor and the negative electrode side contactor from the state where all the contactor groups are opened and the connection between the load device and the secondary battery is disconnected, and the load device and the It is an instruction input to instruct the transition to the state where the secondary battery is connected,
When the instruction is input, the contactor failure determination unit determines that no failure has occurred in the contactor group, and then closes the positive contactor and the negative contactor to close the load device and the secondary battery. A battery connection part for connecting
The contactor failure determination apparatus according to claim 1. The load device is a drive motor for driving the vehicle, and the battery is a drive battery for the vehicle;
The drive motor is a direct drive motor that directly transmits the rotation of the output shaft to the axle of the vehicle.
The contactor failure determination apparatus according to claim 1 or 2, wherein When the contactor failure determination unit determines that a failure has occurred in any of the contactor groups, the contactor failure determination unit further includes notification means for notifying a user.
The contactor failure determination device according to any one of claims 1 to 3, wherein A positive-side contactor provided on a positive-side power supply line that connects a positive electrode of a battery that supplies power to a load device and a positive electrode of the load device, and a negative-side power supply line that connects a negative electrode of the battery and a negative electrode of the load device A contactor failure determination method for determining a failure of a contactor group including a negative electrode side contactor provided above,
A contactor opening and closing step for sequentially opening and closing the contactor group;
A current detection step of detecting a current flowing through the positive power line on the battery side relative to the positive contactor or the negative power line on the battery side relative to the negative contactor;
A failure determination step of determining whether or not a failure has occurred in any of the contactor groups, based on a change in the current accompanying opening and closing of the contactor groups;
The contactor failure determination method characterized by including.

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