JP4565963B2 - Failure detection processor - Google Patents

Description

The present invention is a hybrid vehicle, to fault detection apparatus that put the motor driving apparatus of a vehicle such as an electric vehicle.

  In recent years, so-called hybrid vehicles and electric vehicles are provided with a battery for power supply and an AC motor (synchronous motor) for driving and driving, and the motor drive device. For example, a high-voltage DC power supply of about 200 V is supplied to the inverter of the motor control unit (the motor control unit and the master control unit of Patent Document 1) through a power supply unit provided with the system main relay of Patent Document 1. The AC output of this inverter is supplied to the motor.

  In addition, battery voltage detection information between terminals of the power supply battery is transmitted from the battery voltage detection means formed by the so-called battery control ECU to the motor control section, and the inverter input voltage detection means of the motor control section transmits the DC input of the inverter. The voltage is detected, and the motor current supplied from the inverter to the motor is detected by the current detection means of the motor control unit.

  Then, the drive control means of the motor control unit detects the battery voltage, the input DC voltage, the motor current, controls the inverter according to the motor torque command value set based on the battery voltage, and drives the motor. .

  In this case, it is proposed to detect a power supply abnormality (failure) from the difference between the voltage on the power source side of the system main relay (corresponding to the battery voltage) and the voltage on the load side (corresponding to the DC voltage of the inverter). (For example, refer to Patent Document 1).

JP 2001-327001 A (paragraphs [0030]-[0056], FIG. 1, FIG. 2, FIG. 5)

  In the detection of the power supply abnormality as in the conventional proposal (described in Patent Document 1), the power supply means abnormality (high voltage wiring system failure) such as disconnection of the high voltage connector of the power supply means or contactor contact failure, and the inverter input voltage detection means Is not detected separately from the abnormality (inverter input voltage detection system failure).

  Therefore, there is a problem that even if a detected power supply abnormality is notified to a service person such as a driver or a repair shop, the cause of the failure cannot be easily determined.

  In addition, in the case of the inverter input voltage detection system failure, the detection result of the inverter input voltage detection means of the motor control unit is incorrect, there is no high-voltage wiring system failure, and the DC voltage of the inverter input is normal. Nevertheless, there is a problem that the normal control of the inverter becomes difficult based on the erroneous detection result of the inverter input voltage detection means, and the motor drive is stopped in some cases.

  An object of the present invention is to distinguish and detect an abnormality of a power supply means (high-voltage wiring system failure) and an abnormality of detection of an inverter input voltage detection means (inverter input voltage detection system failure) in a motor drive device for a vehicle. In addition, when the inverter input voltage detection system failure is detected, the inverter is normally controlled so as not to be affected by the failure, and the driving of the motor is continued.

In order to achieve the above object, the failure detection processing device of the present invention feeds a DC power from a power supply battery to an inverter of a motor control unit via a power supply means, and an AC output of the inverter is used for driving. Power is supplied to the motor, battery voltage detection information between the terminals of the power supply battery is transmitted from the battery voltage detection means to the motor control section, and the inverter input voltage detection means of the motor control section inputs the DC voltage of the inverter. And a motor current supplied from the inverter to the motor is detected by the current detection unit of the motor control unit, and the battery voltage, the DC voltage, and the motor current are detected by the drive control unit of the motor control unit. The inverter is controlled according to the detected and set motor torque command value, and is installed in the motor drive device of the vehicle that drives the motor. It obtained a failure detection processing apparatus, first when the motor control unit, said detected battery voltage, there is a predetermined voltage or more batteries voltage detecting system of the difference abnormality detection of the DC voltage is normal An individual that detects the establishment of the first abnormality detection condition and detects the establishment of the second abnormality detection condition when the motor torque command value is equal to or greater than a predetermined value and the detected motor current is equal to or greater than a threshold value. When the abnormality detection unit and the individual abnormality detection unit detect only the establishment of the first abnormality detection condition, the abnormality of the power supply unit is detected, and the individual abnormality detection unit simultaneously satisfies the both abnormality detection conditions. And a general abnormality detecting means for detecting an abnormality of the inverter input voltage detecting means when detecting an abnormality (claim 1).

Further, the failure detection processing device of the present invention provides the drive control means of the motor control unit with the detected DC voltage of the input of the inverter when the abnormality of the inverter input voltage detection means is detected by the general abnormality detection means. It is characterized by providing fail-safe processing means for controlling the inverter in place of the battery voltage between the terminals of the power supply battery (claim 1 ).

First, according to the configuration of claim 1, when an abnormality (high voltage wiring system failure) of the power supply means occurs and the power supply battery and the inverter are disconnected, the inverter is compared with the battery voltage. Therefore, even if the battery voltage detection system is normal, there is a difference between the detected battery voltage and the detected DC voltage of the inverter. In addition, the DC voltage of the actual inverter input is small, the motor current supplied to the motor from the inverter is reduced (or off), the motor does not rotate normally, and in some cases the rotation stops and the detected motor The current becomes smaller than the threshold value.

  Therefore, when an abnormality (high-voltage wiring system failure) occurs in the power supply means, only the first abnormality detection condition is established, and the abnormality can be detected from the establishment of only the first abnormality detection condition. .

  On the other hand, when an abnormality of the inverter input voltage detection means (inverter input voltage detection system failure) occurs, the DC voltage of the inverter input is not actually small, but the inverter input voltage detection means erroneously detects the input DC voltage. Then, a difference occurs between the detected battery voltage and the detected DC voltage of the input of the inverter, and the first abnormality detection condition is satisfied. Also, the actual DC voltage input to the inverter is large, so that sufficient motor current is supplied from the inverter to the motor according to the motor torque command value, and the motor is driven when the detected motor current exceeds the threshold value. The second abnormality detection condition for determining whether or not the motor is in a driving state is also satisfied (motor driving state).

  Therefore, when an abnormality in the detection of the inverter input voltage detection means (inverter input voltage detection system failure) occurs, both the first and second abnormality detection conditions are satisfied. Abnormalities can be detected.

  Therefore, it is possible to distinguish and detect an abnormality in the power supply means (high-voltage wiring system failure) and an abnormality in the inverter input voltage detection means (inverter input voltage detection system failure). By informing a service person such as this, it is possible to easily investigate the cause of the failure.

Next, according to the configuration of claim 2, when the abnormality of the inverter input voltage detecting means is detected, the erroneously detected DC voltage of the inverter input is detected between the terminals of the power source battery by fail-safe processing. Since it is replaced by battery voltage, the inverter is normally controlled by the drive control means of the motor control unit and the motor is driven properly without being affected by the abnormality of the inverter input voltage detection means. be able to.

  Next, in order to describe the present invention in more detail, an embodiment thereof will be described in detail with reference to FIGS.

  FIG. 1 is a block diagram of a motor drive device 2 when applied to a hybrid vehicle 1, and FIG. 2 is a flowchart for explaining failure detection processing in FIG.

  A hybrid vehicle 1 shown in FIG. 1 is formed by directly connecting an engine 3 and, for example, a three-phase AC motor (synchronous motor) 4 for driving and driving to a drive shaft. The motor drive device 2 is a microcomputer that controls the whole. A vehicle control ECU 5 having a configuration, a power source battery 6, and a motor control unit 8 having an inverter configuration connected to the battery 6 via a normally open contactor unit 7 are provided.

  The power source battery 6 is composed of, for example, a storage battery with a high voltage output of 200 V, and the battery voltage Vb between the terminals, the liquid temperature, and the like are detected and monitored by well-known battery control of the battery control ECU 9 having a microcomputer configuration, and charge / discharge control is performed. Is done.

  Further, the battery control ECU 9 forms battery voltage detection means, and analog or digital detection information of the battery voltage Vb of the detection means is wired or wirelessly transmitted to the motor control ECU 10 having a microcomputer configuration of the vehicle control ECU 5 and the motor control unit 8. Is transmitted.

  Next, the contactor unit 7 and the power supply cable between the power source battery 6 and the inverter 11 of the motor control unit 8 form a power supply unit, and the contactor unit 7 is composed of, for example, a relay switch, and has positive and negative main contacts 7p. , 7n and auxiliary contact 7s for preliminary charging, and open / close control is performed by the vehicle control ECU 5.

  Specifically, when the engine key is inserted to start the vehicle 1, the vehicle control ECU 5 initially closes the auxiliary contact 7s and the main contact 7n, and then closes the main contact 7p. The auxiliary contact 7s is opened, and thereafter, the main contacts 7p and 7n are kept closed until the engine key is pulled out.

  When the auxiliary contact 7s and the main contact 7n are closed by the start command of the vehicle 1, the DC output of the power supply battery 5 is supplied to the power supply capacitor 11a of the inverter 11 via the auxiliary contact 7s and the current limiting resistor 7r. And the charging current of the capacitor 11a flows to the power source battery 5 through the main contact 7n, preventing the occurrence of an excessive inrush current and precharging the power source capacitor 11a.

  Further, when the power supply capacitor 11a is charged to a predetermined voltage by this preliminary charging, the main contact 7p is closed and the auxiliary contact 7s is opened, and thereafter, the DC output of the power supply battery 5 is limited. Instead, the power supply capacitor 11a of the inverter 11 is charged via the main contact 7p.

  Next, the DC voltage Vdc at the input of the inverter 11 formed by the voltage between the terminals of the power supply capacitor 11a is detected by the inverter input voltage detection circuit 12 forming the inverter input voltage detection means, and the detected voltage vdc is detected by the vehicle control ECU 5. And sent to the motor control ECU 10.

  Further, when the engine key is inserted and the start of the vehicle 1 is instructed, the vehicle control ECU 5 outputs and sets the start torque command value Tj to the motor control ECU 10, and thereafter the travel mode and detected voltage of the vehicle 1. Based on vb, vdc, etc., the torque command value Tj set in the motor control ECU 10 is variably adjusted.

  The motor control ECU 10 forms drive control means and individual abnormality detection means, comprehensive abnormality detection means, and fail-safe processing means, which will be described later. The individual abnormality detection means, comprehensive abnormality detection means, and fail-safe processing means are failure detection processing devices. Form.

  The detected voltages vb and vdc, the torque command value Tj, and the current detectors 13u and 13v among the three-phase U, V and W motor currents Iu, Iv and Iw supplied from the inverter 11 to the motor 4. Based on the detected currents iu and iv of the two-phase U and V detected, and the detected rotation speed rpm of the rotation detector 14 attached to the motor 4, the drive control hand is configured to use the battery voltage Vb, the input DC voltage Vdc, According to the detection of the motor currents Iu and Iv and the motor torque command value Tj that has been set, the switching elements SW1 to SW1 of the three-phase full bridge circuit 11b of the inverter 11 are generated so that the motor 4 generates a torque of the torque command value Tj. The SW 6 is controlled to supply the three-phase AC inverter output to the motor 4 to drive the motor 4.

  Next, individual abnormality detection means, comprehensive abnormality detection means, and fail-safe processing means formed by the motor control ECU 10 will be described. These means are formed by software processing when the motor control ECU 10 executes a preset failure detection processing program.

<Individual abnormality detection means>
This means detects the establishment of the first abnormality detection condition when the difference between the detected battery voltage Vb and the input DC voltage Vdc is not less than a predetermined voltage for abnormality detection and the battery voltage detection system is normal, The establishment of the second abnormality detection condition is detected when the motor torque command value Tj is equal to or greater than a predetermined value and the detected motor currents Iu, Iv, Iw are equal to or greater than a threshold value.

  That is, the difference Δb · dc (= | vb−vdc |) between the detected battery voltage Vb and the detected voltage vb, vdc, which is the input DC voltage Vdc, is calculated and converted to the calculated difference Δb, dc and the detected voltage. It is compared with a predetermined voltage vref for abnormality detection to determine whether Δb, dc> vref.

  When the information of the detection voltage vb is transmitted by wire, it is determined whether or not the battery voltage detection system is normal by detecting data errors such as so-called disconnection detection or information parity check, and when the detection voltage vb is transmitted wirelessly. Whether or not the battery voltage detection system is normal is determined by the data error detection.

  Then, “Δb · dc> vref and the battery voltage detection system is normal” is set as the first abnormality detection condition, the battery voltage detection system is normal, the detected battery voltage Vb and the input DC voltage Vdc are When this difference is large, the establishment of this condition is detected.

  Here, the difference between the detected battery voltage Vb and the input DC voltage Vdc is an abnormality of the power supply means such as a contact failure of the contactor 7 with the inverter 11 or disconnection of the high voltage connector of the power supply cable (high voltage wiring). System voltage) and the detected voltage vdc becomes abnormal, and the inverter input voltage detection circuit 12 serving as the inverter input voltage detection means is abnormal (inverter input voltage detection system fault) and the detected voltage vdc is abnormal. When it becomes, it becomes larger than the predetermined voltage vref.

  Next, it is determined whether or not Tj> Tref by comparing the motor torque command value Tj set by the vehicle control ECU 5 with a predetermined value Tref set for detection of under torque.

  Further, if any of the motor currents Iu, Iv, Iv of the three phases U, V, W is equal to or larger than the set threshold value, it is determined that the motor 4 is driven. The detection currents iu and iv are compared with the normal drive threshold value iref set in terms of the detection currents iu and iv to determine whether iu ≧ iref or iv ≧ iref is detected. Determine.

  Then, “Tj> Tref and detection of any one of iu ≧ iref and iv ≧ iref” is set as the second abnormality detection condition, the torque command value Tj is sufficiently large, and the motor currents Iu, Iv, Iv If either of them is equal to or greater than the threshold value, it is recognized that a sufficient motor current is output from the inverter 11 to the motor 4 to drive the motor 4, and the establishment of this condition is detected.

  Here, if the motor 4 is driven, the abnormality of the power supply means (high voltage wiring system failure) has not occurred.

<Total abnormality detection means>
This means detects an abnormality of the power supply means when the individual abnormality detection means detects only the establishment of the first abnormality detection condition, and an inverter when the individual abnormality detection means detects the simultaneous establishment of both abnormality detection conditions. An abnormality of the input voltage detection means is detected.

  That is, if the first abnormality detection condition is satisfied and the second abnormality detection condition is not satisfied, an abnormality (high-voltage wiring system failure) of the power supply means has not occurred. When the occurrence of an abnormality (inverter input voltage detection system failure) is detected and the first and second abnormality detection conditions are satisfied at the same time, the occurrence of an abnormality (high-voltage wiring system failure) in the power supply means is detected.

  In the case of this embodiment, by detecting the occurrence of each abnormality, another abnormality detection output of the abnormality is output to the vehicle control ECU 5, and the abnormality alarm process of the ECU 4 is provided, for example, on the dashboard of the vehicle 1. The lamps of the inverter input voltage detection system failure and high voltage wiring system failure on the display panel 15 are turned on, and the driver and service personnel at the repair shop display the failure separately according to the inverter input voltage detection system failure and high voltage wiring system failure. This notification makes it possible to easily investigate the cause of failure.

<Fail safe processing means>
This means uses the detected DC voltage Vdc of the inverter 11 when the abnormality of the inverter input voltage detection means (inverter input voltage detection system failure) is detected by the total abnormality detection means. The inverter 11 is controlled in place of the battery voltage Vb.

  That is, when an inverter input voltage detection system failure occurs, the DC voltage Vcd at the input of the inverter 11 is actually normal and not small, so the detection voltage vdc is replaced with the detection voltage vb.

  Based on this rewriting, the drive control means converts the detected battery voltage Vb and the DC voltage Vdc input to the inverter 11 to the detected voltage vb, and refers to the motor current command value map which is a function of the inverter input voltage. The inverter 11 is normally controlled without being affected by the failure of the inverter input voltage detection system, and the motor 4 is properly driven.

  Therefore, the engine 3 can be reliably started, and the motor output accuracy during so-called assist operation and regenerative operation can be maintained with high accuracy, without being affected by the failure of the inverter input voltage detection system. Ensuring energy management.

  By the way, the failure detection processing by the individual abnormality detection means, the general abnormality detection means, and the fail safe processing means is shown in a flowchart as shown in FIG. 2, for example.

  Then, steps S1 and S2 in FIG. 2 are detection processing of establishment of the first abnormality detection condition of the individual abnormality detection means. When the first abnormality detection condition is established, the individual abnormality detection means performs steps S3 and S4. When the first abnormality detection condition is satisfied when the abnormality detection condition 2 is satisfied and the first abnormality detection condition is satisfied, the comprehensive abnormality detection means detects an abnormality of the power supply means (high-voltage wiring system failure) in step S5. When the first and second abnormality detection conditions are satisfied at the same time, the general abnormality detection means detects the occurrence of an abnormality (inverter input voltage detection system failure) in the inverter input voltage detection circuit 12 in step S6.

  Further, when the occurrence of the inverter input voltage detection system failure is detected, the fail safe processing means executes the fail safe processing in step S7.

  Further, based on the detection of the occurrence of each of the high-voltage wiring system failure and the inverter input voltage detection system failure, the general abnormality detection means executes the abnormality detection (failure alarm) output in step S8 and generates individual abnormality detection outputs. .

  As described above, in the embodiment, the high-voltage wiring system failure and the inverter input voltage detection system failure can be distinguished and detected, and the detected abnormality is displayed as an alarm on the display panel 15 to display a driver or repair shop. By notifying the service person such as, it is possible to easily investigate the cause of the failure.

  In addition, when an inverter input voltage detection system failure occurs, the inverter is normally controlled by fail-safe processing to continue the proper driving of the motor, to reliably start the engine 3, and at the time of so-called assist operation, The motor output accuracy during the regenerative operation can be maintained with high accuracy, and the energy management of the vehicle 1 can be reliably performed without being affected by the failure of the inverter input voltage detection system.

  The present invention is not limited to the above-described embodiment, and various modifications other than those described above can be made without departing from the spirit thereof. For example, in the above-described embodiment, the engine 3 and the motor However, the present invention can be similarly applied to an electric vehicle having a configuration in which the engine 3 is omitted.

  Further, the fail safe processing means may be omitted, and the predetermined voltage vref for abnormality detection, the predetermined value Tref of the motor torque command value Tj, etc. may be set appropriately based on experiments or the like.

  Of course, the failure detection procedure, the notification method, and the like are not limited to those of the embodiment.

  By the way, in order to reduce the number of equipment parts of the own vehicle 1, for example, the detection result of the rotation detector 14 of FIG.

It is a block diagram of one embodiment of this invention. 3 is a flowchart for explaining failure detection processing in FIG. 1.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Hybrid vehicle 2 Motor drive device 4 Motor 6 Battery for power supply 8 Motor control part 9 Battery control ECU
10 Motor control ECU
11 Inverter 12 Inverter input voltage detection circuit 13u, 13v Current detector Tj Torque command value Vb Battery voltage Vdc DC voltage Iu, Iv, Iw Motor current

Claims (2)

DC power is supplied from the battery for power supply to the inverter of the motor controller through the power supply means,
Supplying the AC output of the inverter to a motor for driving,
Transmitting battery voltage detection information between the terminals of the power supply battery from the battery voltage detection means to the motor control unit,
Detecting the DC voltage of the inverter input by the inverter input voltage detection means of the motor control unit,
Detecting a motor current supplied to the motor from the inverter by current detection means of the motor control unit,
A motor drive device for a vehicle that drives the motor by controlling the inverter according to detection of the battery voltage, the DC voltage, the motor current, and a set motor torque command value by the drive control means of the motor control unit. A failure detection processing apparatus provided in
In the motor control unit,
It said detected battery voltage, the difference between the DC voltage to detect the establishment of the first abnormality detection condition when there is a predetermined voltage or more batteries voltage detecting system abnormality detection is normal, the motor torque command value Individual abnormality detection means for detecting that the second abnormality detection condition is satisfied when the detected motor current is equal to or greater than a threshold value.
When the individual abnormality detection means detects only the establishment of the first abnormality detection condition, the abnormality of the power supply means is detected, and when the individual abnormality detection means detects the simultaneous establishment of both the abnormality detection conditions A failure detection processing apparatus comprising: general abnormality detection means for detecting an abnormality of the inverter input voltage detection means. The failure detection processing device according to claim 1 ,
In the drive control means of the motor controller,
Fail-safe processing means is provided to control the inverter by replacing the detected DC voltage of the inverter input with the battery voltage between the terminals of the power supply battery when an abnormality of the inverter input voltage detection means is detected by the general abnormality detection means. A failure detection processing device characterized by that.

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