JPH1023601A - Controller for motor of electric vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a motor drive relay from being interrupted, when the operation of the control units of a motor is being checked. SOLUTION: A main control unit 11 and a sub-control unit 12 receive a torque command from TPC 21 and individually perform arithmetic operation for motor control. The control units then check whether or not their results of the arithmetic operation are identical. The mask signals output from the control units are set to 'H' during ordinary operations. If any anomaly, such as a mismatch between the results of arithmetic operation, occurs, a relay cut signal is brought into 'H', to interrupt a motor drive relay 24. At the time of operation check, the mask signals from the control units are brought into 'L', to forcedly inhibit the operation of interrupting the motor drive relay 24.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor control device for an electric vehicle, and more particularly to a technique for preventing a motor drive relay from being interrupted when the operation of a motor drive control unit is confirmed.

[0002]

2. Description of the Related Art In a conventional motor control device for an electric vehicle, the occurrence of abnormalities during normal operation of the motor is monitored,
Including a fail-safe circuit that shuts down the motor by stopping power supply to the motor in the event of an abnormality, and confirms whether the control operation of the motor including the monitoring function is performed normally before the motor is operated. There is.

[0003] This operation is confirmed by, for example, as shown in FIG. 5, a main control unit 51 for controlling the drive of the motor when an ignition switch before driving the motor is turned on.
The operation is performed by inputting a signal for operation confirmation to the sub-control unit 52 for monitoring the main control unit and activating the circuit. At this time, the fail-safe circuit operates to shut off the motor drive relay. Signal (relay cut signal)
May be output. The output of the signal for shutting off the energization of the motor causes inconvenience such as making it impossible to perform another diagnosis on the condition that the motor drive relay is ON. Therefore, the motor drive relay is not shut off during the operation check. Is masked.

That is, a main control unit 51 and a sub control unit 52
Is input to an OR circuit 54, and its output is input to an AND circuit 55, and a signal (mask signal) output from another control system 56 for inhibiting a motor drive relay from being cut off is input to an AND circuit. Enter 55. This input is made by communication. Then, the comparison result between the output of the OR circuit 54 and the output from the other control system 56 is output to the motor drive relay as a relay cut signal.

When the operation is confirmed, the cutoff operation of the motor drive relay is prohibited by switching the mask signal from the other control system 56 to "L". In this case, each control unit
The noise signal and the operation confirmation signal output from each control unit are output when the comparison processing of the calculation results in 51 and 52 is performed or when the operation of the relay cut signal output when an abnormality occurs is checked. When the signal is output as a signal and input to the OR circuit 54, the output of the OR circuit 54 becomes "H" and is input to the AND circuit 55.
However, since the mask signal which is the other input signal of the AND circuit 55 is "L", it is possible to prohibit the motor drive relay from being cut off.

Next, a conventional example of another motor control device will be described. The motor control device shown in FIG. 6 uses the operation characteristics of the relay element to prevent the motor drive relay from being cut off by the relay cut signal generated when the operation of the main control unit 61 and the sub control unit 62 is confirmed. Things. In this type of relay, for example, when the connected relay is energized, if the relay cut signal is maintained at “H” for about 50 msec or more, the relay is cut off, while the relay cut signal is about 5 msec or more. When it becomes “L”, the power is turned on.

[0007] By utilizing the operation characteristics of such a relay,
For example, when the motor drive relay is in the energized state, the relay cut signal from the main control unit 61 or the sub control unit 62 is set to “L” before reaching the “H” duration at which the motor drive relay starts the shut-off operation. By doing so, it is possible to prevent the motor drive relay from being shut off when the operation of each control unit is checked.

At the time of actual operation confirmation, the operation confirmation processing of the main control unit 61 and the sub control unit 62 is divided into a plurality of
This is performed by reducing the amount of operation confirmation processing per cycle and shortening the “H” duration of the relay cut signal.

[0009]

However, in the configuration shown in FIG. 5 in which the cutoff operation of the motor drive relay is restricted by the other control system 56, the operation of the mask circuit of the other control system 56 is not confirmed. However, there is a possibility that it is difficult to ensure the reliability of the operation, and since the signal from the other control system 56 is input to the AND circuit 55 by communication, it takes time to start up the communication and the communication itself. This makes it difficult to increase the processing speed.

On the other hand, in the configuration using the operation characteristics of the relay shown in FIG. 6, since a short-time signal is output once to confirm the operation, a long time is required for the operation confirmation. As the number of locations to be checked for operation increases, the operation check time also increases. In order to shorten the operation check time as much as possible, it is conceivable to set the pulse width of the operation check signal to be short. However, when the pulse width is set to be short in this way, for example, an individual "L" region in a noise signal generated at the time of operation confirmation may be recognized as noise, and the signal is regarded as a continuous "H" region. Judgment may cause the motor drive relay to malfunction.

Accordingly, an object of the present invention is to provide a motor control device for an electric vehicle which prevents a motor drive relay from being interrupted when the operation of a motor control unit is checked in view of the above-mentioned conventional problems.

[0012]

In order to achieve the above object, according to the first aspect of the present invention, as shown in FIG. 1, a main control for outputting a relay control signal for controlling the driving of a motor by a relay is provided. Unit 11, a sub-control unit 12 for monitoring a main control unit having a function equivalent to the main control unit 11,
When an abnormality is detected in at least one of the main control unit and the sub-control unit, a relay shut-off signal is output to output a relay shut-off signal to shut off the relay, and a motor control operation including the relay shut-off function is checked. The motor control device for an electric vehicle, comprising: an operation check unit 14; and the main control unit 11 and the sub control unit.
A mask signal generating means 15 for generating a mask signal when the operation is confirmed by the operation confirming means 14;
And a mask control unit for prohibiting a relay cutoff operation by the relay cutoff unit 13 only when a mask signal is output from both the main control unit 11 and the sub control unit 12.
16 and so on.

According to a second aspect of the present invention, a signal of an output circuit connected to the main control unit and the sub-control unit is fed back to the main control unit and the sub-control unit to confirm the operation of the signal. Added feedback confirmation means. According to a third aspect of the present invention, the feedback confirmation unit confirms the operation of the signals by individually feeding back signals from a plurality of locations of the output circuit to the main control unit and the sub control unit. I made it.

[0014]

According to the first aspect of the present invention, when the mask signal is output from both the main control unit and the sub control unit, the motor drive relay cutoff operation is forcibly prohibited. Even when the mask signal of one control unit is erroneously output during the normal operation, the operation is not masked, and the interruption operation of the motor drive relay is not hindered.

Further, since the mask generation means is provided in each control unit, it is not necessary to perform the processing of the mask signal by external communication, so that the operation confirmation processing can be sped up and the mask signal generation at the time of operation confirmation is performed. Since the operation of the means can be confirmed together, the reliability of the motor control device can be further improved. According to the second aspect of the present invention, the output signals from the main control unit and the sub-control unit can be compared with the output signals of the subsequent circuits to detect an abnormality of these subsequent circuits. The reliability of the entire control device can be further improved.

According to the third aspect of the present invention, it is possible to individually confirm an abnormal portion of the subsequent circuit, and to perform more detailed operation confirmation.

[0017]

FIG. 2 shows an embodiment of the present invention.
This will be described with reference to FIG. First, the configuration of the motor control device according to the first embodiment is shown in FIG. The motor control device according to the present embodiment has a TPC (Torque Processing Control) set according to an accelerator opening, a vehicle speed, and the like.
er) Based on the torque command from 21, the microcomputer calculates the motor current etc.
A main control unit 11 for controlling the operation of the main control unit 11;
And a sub-control unit 12 that monitors the operation of the main control unit 11 by comparing the operation results of the main control unit 11 and a DPRAM (Dual Port RAM) 23.
The main control unit 11 controls on / off of the motor drive relay 24 under a predetermined condition, and controls the drive of the motor 22 by generating a motor current according to the torque by the inverter INV25.

Then, the main control section 11 outputs a motor drive signal for generating a motor current according to the torque command by the INV 25, and a mask signal for inhibiting the shut-off operation of the motor drive relay 24 during an operation check described later. The sub-control unit 12 outputs a similar mask signal and a relay cut signal while outputting a relay cut signal for shutting off the motor drive relay 24 when an abnormality occurs.

Here, the mask signal becomes "L" when the shut-off operation of the motor drive relay 24 is prohibited, and becomes "H" otherwise. Further, the relay cut signal becomes “H” to shut off the motor drive relay 24 when an abnormality occurs, and becomes “L” otherwise. The mask signals from the main control unit 11 and the sub control unit 12 are input to an OR circuit 26, and the relay cut signals from both control units are input to an OR circuit 27. And the OR circuit 26
And the output of the OR circuit 27 are input to the AND circuit 28,
The output signal of the AND circuit 28 is applied to the motor drive relay 24c.
Output to terminal.

The output of the OR circuit 27 and the AND circuit
The output of the OR circuit 29 is input to an OR circuit 29, and the output of the OR circuit 29 is fed back to the main control unit 11 and the sub control unit 12. When the signal at the terminal c of the motor drive relay 24 is in the “L” state, the motor 22
When the terminals are energized, the driving state is established. When the terminal c is in the "H" state, the terminals a and b are shut off and the terminal is stopped.

FIG. 3 shows a specific internal configuration of the motor drive relay 24. Immediately after the operation of the motor control device before the motor is driven, the contact of the relay 31 for cutting the motor drive is always ON.
And other motor drive cut relays 32,33,34,35
Are set to be always shut off. As a result, when the control device is operated, a current is applied between a and b of the motor drive relay 24, and a current flows to the motor 22 by the INV 25.

The operation of the motor control device will be described below. In order to properly control the motor 22 based on the torque command from the TPC 21, the operation of the motor control device itself is first checked. This operation confirmation processing is performed when the motor is not driven, for example, when the ignition switch is turned on. At this time, noise signals and operation confirmation signals are output from the control units 11 and 12. It is necessary to prevent the motor drive relay 24 from being erroneously shut off by this signal and the current to the motor 22 from being cut off.

Therefore, during the operation check, the main control unit 11
And the sub control unit 12 sets the mask signal to "L" and sets O
Input to the R circuit 26, and the mask signal “L” from the OR circuit 26
Is input to the AND circuit 28 to prohibit the shut-off operation of the motor drive relay 24, that is, the shut-off operation of the relay 31. As described above, when the mask signal is in the “L” state,
The main control unit 11 and the sub-control unit 12 receive a command for operation confirmation from the TPC 21 and calculate a signal for controlling the motor 22 by the microcomputer in each of the control units 11 and 12. At this time, each of the control units 11 and 12 converts the calculation result of each microcomputer into a DP.
A comparison is made through the RAM 23 to confirm whether or not the calculation results are the same.

Further, the operation of each element in each control section, the supply voltage, the current, and the like are also shared by the main control section 11 and the sub-control section 12 to confirm whether or not the operation is normal. At this time, if the calculation results of the main control unit 11 and the sub control unit 12 are different, or if an abnormality is detected in each control unit or in the output mask signal itself, a shutdown procedure of the motor control device is performed. For example, the motor control is stopped by executing the control from the control unit in which the abnormality is detected. The execution of this shutdown procedure is performed by each control unit 1.
The control may be performed from another control system (not shown) connected to 1 and 12. In other words, when an abnormality occurs, the motor may not be driven.

On the other hand, the main control unit 11 and the sub control unit 12
Are the same, and when no abnormality is detected inside each control unit, it is determined that each control unit is normal.
, And proceeds to the next feedback process. In the feedback process, first, the relay cut signal output from each of the control units 11 and 12 as an operation confirmation signal is
And the output of the OR circuit 27 is input to the OR circuit 29.
Also, the output from the OR circuit 27 is input to the AND circuit 28,
The output of the AND circuit 28 obtained by setting the mask signal to "H" for a short time is input to the OR circuit 29. By feeding back the output of the OR circuit 29 to each of the control units 11 and 12, an abnormality in a circuit connected to each of the control units 11 and 12 is detected. If a signal corresponding to the operation confirmation signal output from each of the control units 11 and 12 cannot be obtained by the OR circuit 29, it is determined that an abnormality has been detected, and a shutdown procedure of the motor control device is executed in the same manner as described above. Stop motor control.

At the time of the above operation check, the comparison processing between the main control unit 11 and the sub control unit 12 and the control unit 1
A noise signal and an operation confirmation signal are generated by the operation confirmation processing of the circuits connected to the circuits 1 and 12. These signals are output as a relay cut signal even when each control unit is normal. Therefore, it is necessary to prevent the relay 31 from being erroneously shut off by the relay cut signal.

Therefore, in the present embodiment, by setting the mask signals from both control units to "L" and performing the operation confirmation processing, such a malfunction due to the relay cut signal at the time of operation confirmation is prevented. I have. Also, by using a configuration in which a mask signal is output from each control unit,
Unlike a system in which a mask signal is output from another control system by communication, a reduction in processing speed due to communication start-up time or communication itself can be avoided, and the speed of operation confirmation processing can be increased.

Further, except when the output of the AND circuit 28 is input to the OR circuit 29 in the above-described feedback processing, the output of the "H" state of the relay cut signal is output to prevent the relay from malfunctioning. It is not necessary to stop before reaching the H "duration, signals for operation confirmation can be output collectively in a short time, and the operation confirmation processing can be terminated quickly.

The above is the processing for confirming the operation. During normal motor driving, the mask signal is set to “H”, and the calculation result of the main control unit 11 and the calculation result of the sub control unit 12 are compared. Compare. When the calculation results are different, it is determined that an abnormality has occurred, and the control unit that has detected the abnormality outputs a relay cut signal as “H”, and outputs a “c” of the motor drive relay 24 via the OR circuit 27 and the AND circuit 28. By outputting to the terminal, the relay 31 is shut off and the motor 22 is stopped.

Also, in such a normal motor driving, even when the mask signal from one of the control units outputs "L" due to abnormality, the mask signal from each control unit is input to the OR circuit 26. By doing, AND
The circuit 28 is not erroneously masked, and the motor drive relay 24 can be reliably shut off. As described above, in the present embodiment, by performing a masking process, a relay cutoff signal such as a noise signal or an operation confirmation signal output from each control unit when an operation is confirmed is masked so that the relay is cut off erroneously. In addition to this, when an abnormality actually occurs during normal motor driving, the relay can be reliably shut off by a relay cut signal output from each control unit.

Next, a description will be given of a second embodiment in which the occurrence of an abnormality in a subsequent circuit can be distinguished and grasped up to the point of occurrence. FIG. 4 is a configuration diagram in the present embodiment.
The feedback mechanism of FIG. 2 is directly fed back to the main control unit 11 and the sub-control unit 12 without passing through the OR circuit 29, and the output signal from each control unit is compared with the output signal of the subsequent circuit.

With this configuration, since the output states of the OR circuit 27 and the AND circuit 28 are individually input to the main control unit 11 and the sub-control unit 12, it is possible to distinguish and grasp the location where the abnormality has occurred, and to carry out repair work. Can be further simplified.

[Brief description of the drawings]

FIG. 1 is a diagram corresponding to claims of the present invention.

FIG. 2 is a configuration diagram of a motor control device according to the first embodiment.

FIG. 3 is a diagram showing a configuration of a relay device.

FIG. 4 is a configuration diagram of a motor control device according to a second embodiment.

FIG. 5 is a configuration diagram of a motor control device that inputs a mask signal from another control system.

FIG. 6 is a configuration diagram of a motor control device using characteristics of a relay element.

[Explanation of symbols]

 11 Main control section 12 Sub-control section 13 Relay cutoff means 14 Operation check means 15 Mask signal generation means 16 Mask control means 22 Motor 24 Motor drive relay 26,27 OR circuit 28 AND circuit 31 Relay

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Yasuo Matsunaga Nissan Motor Co., Ltd. 2 Takaracho, Kanagawa-ku, Yokohama-shi, Kanagawa

Claims (3)

[Claims] 1. A main control unit for outputting a relay control signal for controlling driving of a motor by a relay, a main control unit monitoring sub-control unit having a function equivalent to the main control unit, and the main control unit A relay shutoff unit that outputs a relay shutoff signal to shut off the relay when an abnormality is detected in at least one of the unit and the sub control unit; and an operation check unit that checks an operation of motor control including the relay cutoff function. A motor control device for an electric vehicle, comprising: a mask signal generating unit that is provided in each of the main control unit and the sub control unit, and that generates a mask signal at the time of operation confirmation by the operation confirmation unit; Only when a mask signal is output from both the control unit and the sub-control unit, the relay is shut off by the relay shut-off means. The motor control apparatus for an electric vehicle, characterized in that it comprises a mask control means for inhibiting operation, the. 2. The apparatus according to claim 1, further comprising a feedback confirmation unit that feeds back a signal of an output circuit connected to the main control unit and the sub control unit to the main control unit and the sub control unit and confirms the operation of the signal. Item 2. An electric vehicle motor control device according to item 1. 3. The feedback confirmation means according to claim 1, wherein signals at a plurality of locations of said output circuit are individually fed back to said main control section and said sub-control section to confirm the operation of said signals. 3. The motor control device for an electric vehicle according to 2.