JP6642073B2 - Failure diagnosis method for electric power supply system of electric vehicle - Google Patents

Description

The present disclosure relates to a fault diagnosis method of the power supply system of the electric dynamic vehicle.

  A vehicle (EV or HV) using an electric motor as a power source may be in a state where power cannot be transmitted to wheels during traveling (so-called READY off), and the traveling system may stop. The stop of the traveling system in this way is due to an emergency stop operation being performed or a problem occurring in the power supply system.

  Patent Literature 1 discloses an operation receiving unit that receives an operation of starting or stopping a traveling system including an electric motor, a power control unit that controls a power mode determined according to the operation received by the operation receiving unit and a vehicle state, A guidance device is disclosed that includes a stop detection unit that detects a stop of a traveling system during traveling, and a stop factor determination unit that determines whether a stop of the traveling system is caused by an artificial operation based on a power supply mode. ing. According to such a guidance device, it is possible to specify whether or not the cause of the stop of the traveling system is caused by an artificial operation.

Japanese Patent No. 55944432

  In the guidance device disclosed in Patent Document 1, it is possible to specify whether or not the cause of the stop of the traveling system is caused by an artificial operation (emergency stop operation). It is not possible to identify whether a problem has occurred.

In view of the above circumstances, at least one embodiment of the present invention has an object to provide a failure diagnosis method of the power supply system of Ru electrodeposition dynamic vehicle can easily identify where a failure has occurred .

A failure diagnosis method for a power supply system of an electric vehicle according to at least one embodiment of the present invention includes a power switch for instructing power supply, a power control unit connected to an ON terminal of the power switch, A power control relay, wherein a coil is connected to an on terminal of the power switch via an internal circuit of the unit, and a control device including a motor control unit is connected to a contact contacted and separated by the coil. A failure diagnosis method for a system, comprising: an output unit configured to output an input signal for connection confirmation from each of the power switch, the coil, and the contact, and a traveling determination step of determining whether the electric vehicle is traveling. And transmitting the driving force of the motor to the wheels when it is determined that the vehicle is traveling in the traveling determination step. And determining a state determination step of determining a state or not possible, when it is determined that it is not possible status transmission by the state determination step, an input signal output from the power switch, an input signal output from said coil, said A diagnosis step of diagnosing the output in the order of the input signals output from the contact points to specify a failure portion.

According to the above method SL, power switch, coil, and an output unit for outputting the input signal for connection confirmation from each disposed in contact, a driving determining step of determining whether or not the electric vehicle is either running, running determination A state determination step for determining whether or not the driving force of the motor can be transmitted to the wheels when it is determined that the vehicle is traveling in the step, and an output from the power switch when it is determined that the state cannot be transmitted in the state determination step. Diagnosis step of diagnosing the output in the order of the input signal output from the coil, the input signal output from the coil, and the input signal output from the contact to specify the fault location, so that the fault location can be easily identified. can do.

  According to at least one embodiment of the present invention, it is possible to easily identify a location where a problem occurs.

1 is a circuit diagram schematically illustrating a power supply system of an electric vehicle according to a first embodiment of the present invention. 4 is a flowchart schematically illustrating a procedure for diagnosing a power supply system of the electric vehicle according to the first embodiment of the present invention. FIG. 4 is a circuit diagram schematically illustrating a power supply system of an electric vehicle according to a second embodiment of the present invention.

Hereinafter, some embodiments of the present invention will be described with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in the embodiments or shown in the drawings are not intended to limit the scope of the present invention thereto, but are merely illustrative examples. Absent.
For example, expressions representing relative or absolute arrangement such as “in a certain direction”, “along a certain direction”, “parallel”, “orthogonal”, “center”, “concentric” or “coaxial” are strictly described. Not only does such an arrangement be shown, but also a state of being relatively displaced by an angle or distance that allows the same function to be obtained.
In addition, for example, an expression representing a shape such as a square shape or a cylindrical shape not only represents a shape such as a square shape or a cylindrical shape in a strictly geometrical sense, but also has a concavo-convex portion as long as the same effect can be obtained. A shape including a chamfered portion and the like is also represented.
On the other hand, the expression “comprising”, “comprising”, “including”, “including”, or “having” one component is not an exclusive expression excluding the existence of another component.

[Embodiment 1]
FIG. 1 is a circuit diagram schematically showing a power supply system 1A of an electric vehicle according to Embodiment 1 of the present invention.
As shown in FIG. 1, a power supply system 1A for an electric vehicle according to a first embodiment of the present invention includes a power switch 2, a power control unit 3, and a power control relay 4.

The power switch 2 is a switch for instructing power supply, and is configured to select any one of “LOCK”, “ACC”, “ON”, and “ST”.
The "LOCK" position is a position where a key (not shown) can be inserted and removed, and a handle (not shown) is locked at the "LOCK" position so that the key can be inserted and removed. .
The “ACC” position is a position at which electrical components such as an accessory socket (not shown) can be used, and can be shifted from the “LOCK” position and the “ON” position.
The “ON” position is a position that enables the power supply control unit 3 to supply power, and is configured to be shiftable from the “ACC” position and the “ST” position.
The “ST” position is a position for starting the starter in an electric vehicle equipped with an engine such as a hybrid vehicle, and is configured to be able to shift only from the “ON” position.
Note that the power supply system of the electric vehicle according to the present embodiment uses a rotary power switch as the power switch 2, but is not limited to this, and for example, a push power switch may be used.

The power supply control unit 3 (hereinafter, referred to as “EV-ECU 3”) is a control device that comprehensively manages power supply of the electric vehicle. The EV-ECU 3 is connected via an harness 11 to an ON terminal provided at the “ON” position of the power switch 2, and shifts the power switch 2 from the “ACC” position to the “ON” position. Turns on.
The EV-ECU 3 totally controls control devices such as a motor control unit 5 (hereinafter, referred to as “MCU5”), a battery management unit 6 (hereinafter, referred to as “BMU6”), and an on-board charger 7 (hereinafter, referred to as “OBC7”). (Not shown) and an internal circuit 31 for supplying power to the power control relay 4. The internal circuit 31 is provided with a diode 311, and the upstream side of the diode 311 is connected to the harness 11.

  The power control relay 4 is for opening and closing the electric circuit 12 to which the MCU 5, the BMU 6, and the OBC 7 are connected, and includes an exciting coil 41 and a contact 42 separated by the exciting coil 41. The exciting coil 41 is provided on the downstream side of the diode 311 of the internal circuit 31, and the contact point 42 is provided on the upstream side of the MCU 5, BMU 6, and OBC 7.

  The MCU 5 includes output units 32 to 34 for outputting input signals for connection confirmation from the power switch 2, the exciting coil 41 of the power control relay 4, and the contact 42 of the power control relay 4.

  The first output unit 32 for outputting an input signal for connection confirmation from the power switch 2 is provided upstream of the exciting coil 41 of the power control relay 4 and downstream of the ON terminal of the power switch 2. Specifically, it is provided at a connection point between the harness 11 and the internal circuit 31. The first output unit 32 has a resistor 321 for stepping down to a predetermined voltage (for example, 1 to 4 V) and a resistor 322 for generating an input signal for connection confirmation. As a result, an input signal (voltage signal) is generated between the first output unit 32 and the ground.

A second output unit 33 for outputting an input signal for connection confirmation from the excitation coil 41 of the power control relay 4 is provided downstream of the excitation coil 41 of the power control relay 4.
Specifically, it is provided at the other end of the harness 13 whose one end is connected to the exciting coil 41 of the power control relay 4. The second output section 33 has a resistor 332 for generating an input signal for connection confirmation. As a result, an input signal (voltage signal) is generated between the second output unit 32 and the ground.

  The third output unit 34 that outputs an input signal for connection confirmation from the contact 42 of the power control relay 4 is provided in an electric circuit that is opened and closed by the contact 42 of the power control relay 4. Specifically, it is provided at the other end of the harness 14 having one end connected to the electric circuit 12 to which the MCU 5, the BMU 6, and the OBC 7 are connected. The third output unit 34 has a resistor 342 for generating an input signal for connection confirmation. As a result, an input signal (voltage signal) is generated between the third output unit 33 and the ground.

FIG. 2 is a flowchart schematically illustrating a procedure for diagnosing the power supply system 1A of the electric vehicle according to the first embodiment of the present invention. At the time of diagnosis, a device for measuring a voltage signal such as a tester is used.
As shown in FIG. 2, the electric power supply system 1A of the electric vehicle according to the embodiment of the present invention performs diagnosis when traveling becomes impossible (Step S2: No) while the electric vehicle is traveling (Step S1: Yes). Be executed.

  When the power switch 2 is in the “ACC” position or the “LOCK” position (Step S3: Yes), it is diagnosed that the high voltage by the user operation has been terminated.

  When the power switch 2 is not in the “ACC” position or the “LOCK” position (Step S3: No), an input signal generated between the first output unit 32 and the ground (hereinafter, “switch input”) Is diagnosed (step S4). If the switch input is not Hi (Step S4: No), that is, if the input signal generated between the first output unit 32 and the ground is Lo, an abnormality (failure) of the power switch 2 and the power switch 2 It is diagnosed that the harness 11 or the connector (not shown) between the ECU and the EV-ECU 3 is abnormal (disconnection).

  If the switch input is Hi (Step S4: Yes), an input signal (hereinafter, referred to as "coil input") generated between the second output unit 33 and the ground is diagnosed (Step S5). When the coil input is not Hi (Step S5: No), that is, when the input signal generated between the second output unit 33 and the ground is Lo, the abnormality (failure) of the exciting coil 41 of the power control relay 4 ), Diagnosis is made that the harness 13 or the connector (not shown) between the exciting coil 41 of the power control relay 4 and the EV-ECU 3 is abnormal (disconnection).

  If the coil input is Hi (Step S5: Yes), an input signal (hereinafter referred to as “contact input”) generated between the third output unit 34 and the ground is diagnosed (Step S6). If the contact input is not Hi (Step S6: No), that is, if the input signal generated between the third output unit 34 and the ground is Lo, the contact 42 of the power control relay 4 is abnormal (failure). It diagnoses that the harness 13 or the connector (not shown) between the contact 42 of the power control relay 4 and the EV-ECU 3 is abnormal.

  If the contact input is Hi (Step S6: Yes), it is diagnosed as a temporary failure of the EV-ECU3.

  As described above, the power supply system 1 </ b> A of the electric vehicle according to the embodiment of the present invention transmits the input signal for connection confirmation from the power switch 2, the excitation coil 41 of the power control relay 4, and the contact 42 of the power control relay 4. Since the output sections 32 to 34 for outputting are included, it is possible to easily specify a portion where a problem has occurred.

  In addition, since the first output unit 32 is provided upstream of the exciting coil 41 of the power control relay 4 and downstream of the ON terminal of the power switch 2, a problem occurs in the power switch 2 or its connection path. In this case, an abnormality occurs in the input signal generated between the first output unit 32 and the ground. Accordingly, when a failure occurs in the power switch 2 or the connection path thereof, the location where the failure occurs (the power switch 2 or the connection path thereof) can be easily specified.

  Further, since the second output unit 33 is provided downstream of the exciting coil 41 of the power control relay 4, the second output unit 33 is provided when a problem occurs in the exciting coil 41 of the power control relay 4 or a connection path thereof. An abnormality occurs in the input signal generated between the unit 33 and the ground. Thus, if a problem occurs in the excitation coil 41 of the power control relay 4 or the connection path thereof, the location where the problem occurs (the excitation coil 41 of the power control relay 4 or the connection path thereof) is easily specified. be able to.

  Further, since the third output unit 34 is provided in the electric circuit 12 which is opened and closed by the contact 42 of the power control relay 4, the third output unit 34 is connected to the contact 42 of the power control relay 4 or the connection route thereof when a failure occurs. 3 has an abnormality in the input signal generated between the output unit 34 and the ground. Thereby, when a failure occurs in the contact 42 of the power control relay 4 or the connection path thereof, the location of the failure (the contact 42 of the power control relay 4 or the connection path thereof) can be easily specified. it can.

[Embodiment 2]
FIG. 3 is a circuit diagram schematically showing a power supply system 1B of the electric vehicle according to Embodiment 2 of the present invention. In addition, the same reference numerals are given to portions common to the power supply system 1B of the electric vehicle according to Embodiment 1 of the present invention described above, and description thereof will be omitted.

  As shown in FIG. 3, the electric power supply system 1 </ b> B of the electric vehicle according to the second embodiment of the present invention includes a diagnosis unit 35 to diagnose whether there is a failure based on the input signals output from the output units 32 to 34 described above. 37.

  The first diagnostic unit 35 is for diagnosing whether or not a failure has occurred in the power switch 2 or the connection path thereof, and an input signal generated between the first output unit 32 and the ground ( Based on the switch input), a diagnosis is made as to whether or not a failure has occurred in the power switch 2 or its connection path. Specifically, when the switch input output from the first output unit 32 is not Hi, that is, when no voltage is output from the first output unit 32, an abnormality (failure) of the power switch 2 Diagnosis is made that the harness 11 or the connector (not shown) between the EV 2 and the EV-EC 3 is abnormal (disconnection).

  The second diagnostic unit 36 is for diagnosing whether or not a problem occurs in the excitation coil 41 of the power control relay 4 or the connection path thereof, and generates a signal between the second output unit 33 and the ground. Based on the input signal (coil input), it is diagnosed whether or not the excitation coil 41 of the power control relay 4 or the connection path thereof has a problem. Specifically, when the coil input output from the second output unit 33 is not Hi, that is, when the voltage is not output from the second output unit 33, the abnormality of the exciting coil 41 of the power control relay 4 ( Failure is diagnosed as an abnormality in the harness 13 or the connector (not shown) between the exciting coil 41 of the power control relay 4 and the EV-ECU 3.

  The third diagnostic unit 37 is for diagnosing whether or not the contact 42 of the power control relay 4 or a connection path thereof has a problem, and is generated between the third output unit 33 and the ground. Based on the input signal (contact input), whether the contact 42 of the power control relay 4 or its connection path has a failure is diagnosed. Specifically, when the contact input output from the third output unit 34 is not Hi, that is, when the voltage is not output from the third output unit 33, the abnormality (failure) of the contact 42 of the power control relay 4 ), Diagnosis is made that the harness or the connector (not shown) between the contact 42 of the power control relay 4 and the EV-ECU 3 is abnormal.

  The first diagnostic unit 35, the second diagnostic unit 36, and the third diagnostic unit 37 are collectively controlled by the diagnostic unit 38, and the first diagnostic unit 35, the second diagnostic unit 36, and the third diagnostic unit The control is performed so that the diagnosis is performed in the order of the unit 38. This is because when the power switch 2 fails, not only the switch input output from the first output unit 32 becomes Lo, but also the coil input output from the second output unit 33 and the third output unit. This is because the contact input output from the terminal 34 becomes Lo, and it becomes impossible to specify a defective portion. Similarly, when the excitation coil 41 of the power control relay 4 fails, the switch input output from the first output unit 32 becomes Hi, but the coil input output from the second output unit 33 and the 3, the contact input output from the output unit 34 becomes Lo, so that it is not known whether the excitation coil 41 of the power supply control relay 4 has a defect or the contact 42 has a defect.

  The power supply system 1 </ b> B of the electric vehicle according to the embodiment of the present invention described above is provided with the diagnosis units 35 to 37 for diagnosing whether or not there is a failure in the power switch 2, the excitation coil 41 of the power control relay 4, and the contact of the power control relay 4. , It is possible to easily identify a portion where a defect has occurred.

  The present invention is not limited to the embodiments described above, and includes embodiments in which the above-described embodiments are modified, and embodiments in which these embodiments are appropriately combined.

DESCRIPTION OF SYMBOLS 1 Power supply system 11 Harness 12 Electric circuit 13 Harness 14 Harness 2 Power switch 3 Power control unit (EV-ECU)
31 Internal circuit 311 Diode 32 First output part 321 Resistance 322 Resistance 33 Second output part 332 Resistance 34 Third output part 342 Resistance 4 Power control relay 41 Excitation coil 42 Contact 5 Motor control unit (MCU)
6 Battery management unit (BMU)
7 On-board charger (OBC)

Claims (1)

A power switch for instructing power supply,
A power control unit connected to an on terminal of the power switch;
A power supply control relay, wherein a coil is connected to an ON terminal of the power switch through an internal circuit of the power supply control unit, and a control device including a motor control unit is connected to a contact which is separated and contacted by the coil;
A failure diagnosis method for a power supply system of an electric vehicle including:
An output unit that outputs an input signal for connection confirmation from each of the power switch, the coil, and the contact point is provided,
A travel determination step of determining whether or not the electric vehicle is traveling;
A state determination step of determining whether or not the driving force of the motor can be transmitted to the wheels when it is determined that the vehicle is traveling in the travel determination step,
If it is determined not to be state-like that can be transmitted by the state determination step, the diagnostic output input signal outputted from the power switch, an input signal output from the coil, in order of the input signal outputted from said contact Diagnostic steps to identify the failure location
A failure diagnosis method for a power supply system of an electric vehicle, comprising:

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