JPH09107602A - Controller of electric vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make an electric vehicle movable even when its monitor device operates abnormally, by making its computer judge the abnormality of its monitor device from the operation of its monitor device or from the own computational result, and by reporting to its driver the abnormality of its monitor device when sensing only the abnormality of its monitor device to continue its motor drive. SOLUTION: In the inside of a monitor-CPU 18, a sensed current value is transferred to a motor-torque estimating portion 42. Further, a torque command value is transferred respectively to a torque comparator 44 and a control computing portion 30, and a motor rotary speed is transferred to the control computing portion 30. From the torque command value and the motor rotary speed, the control computing portion 30 computes a torque current value and an excitation current value to communicate its computational results to a computation-CPU 16. From the sensed current value, the motor-torque estimating portion 42 estimates a motor real torque to transfer its estimating torque value to the torque comparator 44. The torque comparator 44 judge whether the computation-CPU 16 and a motor driver 12 are respectively abnormal or not. As a result, when only the monitor system is abnormal and the driving system is not abnormal, an electric vehicle can move without help to a safe place or the place of it being repairable therein.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric vehicle controller, and more particularly to an electric vehicle controller suitable for use in an automobile.

[0002]

2. Description of the Related Art Generally, a control device for an electric vehicle is constructed as one or a plurality of CPUs. As a CPU abnormality determination method, a method using a watchdog timer and Japanese Patent Laid-Open No. 5-122
As shown in Japanese Patent No. 801, control data is communicated between two CPUs, and when the control data reaches / does not reach C
A method of determining normality / abnormality of PU is known. In Japanese Patent Application Laid-Open No. 5-122801, the control device is configured as a CPU 1 that issues a torque command and a CPU 2 that controls an inverter based on the torque command.
PU2 means for driving the motor and CPU1 or CPU2
The means for stopping the drive of the motor when the abnormality of either one of the CPUs is determined is shown.

[0003]

In Japanese Unexamined Patent Publication No. 5-122801, the abnormality of the CPU 1 or CPU 2 immediately leads to the abnormal driving of the motor. However, when the control device is configured as the arithmetic device and the monitoring device as in the present invention, the abnormality of the arithmetic device is directly connected to the abnormality of the motor drive, but the abnormality of the monitoring device does not directly lead to the abnormal drive of the motor. . It is better to avoid unnecessary stop of the motor drive system because shutting off the driving power when driving a car causes a problem of stopping at a place where safety cannot be ensured, such as a railroad crossing or a highway.

In order to solve such a problem, it is an object of the drive device and the monitoring device to monitor each other and to enable traveling even if the monitoring device is operating abnormally.

[0005]

In order to solve the above problems, according to claim 1 of the present invention, a motor control calculation is performed based on a torque command value and an input signal value of a motor rotation speed to drive a motor. And a monitoring device for monitoring a motor drive system by comparing a command value and a measured value of at least one of torque and motor current, the arithmetic device being the monitoring device of the electric vehicle. The monitoring device is provided with means for judging an abnormality of the monitoring device from the operation or calculation result, means for notifying the operator of the abnormality when the abnormality is detected, and means for continuing the motor drive.

According to a second aspect of the present invention, there is provided means for limiting the torque command value to a predetermined value or less when the abnormality determining means detects an abnormality.

According to a third aspect of the present invention, there is provided means for monitoring the motor drive system including the arithmetic unit, the gate, the inverter and the motor to determine an abnormality, and means for stopping the driving of the motor when the abnormality is determined.

According to the first aspect of the present invention, the arithmetic unit determines the abnormality of the monitoring device. The abnormality determining means for the monitoring device inside the arithmetic unit detects the abnormality of the monitoring device and notifies the operator of the abnormality, so that the operator's attention is called and the traveling is continued according to the operator's judgment.

According to a second aspect of the present invention, the arithmetic unit limits the torque command value in the arithmetic unit when the monitoring unit determines an abnormality, and limits the output of the motor to drive the motor.
Increase the safety of electric vehicles. Further, in this configuration, when the abnormality determining means inside the control device malfunctions and the monitoring device that is normally operating normally is determined to be abnormal, the torque command value inside the monitoring device is not limited, and the torque command value is not limited. The detected value of the actual torque becomes smaller than the magnitude of the above, the abnormality determination means of the monitoring device determines the abnormality of the control device, and shuts off the drive system of the motor.

According to a third aspect of the present invention, the monitoring device has a control device and means for determining abnormality of the motor drive system. The abnormality determination means inside the monitoring device immediately shuts off the drive system of the motor when the abnormality of the control device is detected.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an embodiment of a control device for an electric vehicle of the present invention, together with a drive device for a motor and an abnormality display device for a user. The control device is an arithmetic CPU which is the arithmetic device in FIG. 1, a monitoring CPU which is a monitoring device, and a DPRAM which is a communication means between the arithmetic CPU and the monitoring CPU.
Consists of The motor drive device in FIG. 1 includes a gate, an inverter, a motor rotation speed sensor, and a current sensor. The abnormality display device for the user in FIG. 1 comprises an LED display. The calculation CPU is composed of a torque limiter, a control calculator, a 2/3 converter, a torque current comparator, an exciting current comparator, and a monitoring CPU abnormality determiner. Surveillance C
The PU is composed of a control calculator, a motor torque estimation unit, a torque comparator, a calculation CPU, and a motor drive unit abnormality determiner. The abnormality display device for the user represents a means for notifying the operator of the abnormality. The motor drive unit abnormality determiner represents an arithmetic unit abnormality determination means. The gate represents a means for stopping the driving of the motor. Torque current comparator, excitation current comparator and monitoring CP
The U abnormality determiner represents the monitoring device abnormality determination means.

The arithmetic unit receives the torque command value, detects the motor rotation speed from the rotation speed sensor, and detects the motor current value from the current sensor. Then, the PWM signal and the gate on / off command signal are output to the motor drive device. Further, a display / non-display command signal for displaying an abnormality is output to the abnormality display device for the user. Inside the control device, the torque command value and the motor rotation speed are transmitted to the calculation CPU and the monitoring CPU, respectively. The detected current value is transmitted only to the monitoring microcomputer. Data transmission from monitoring microcomputer to control microcomputer is D
The torque current value and the exciting current value calculated by the monitoring CPU via the PRAM are transmitted from the monitoring CPU to the processing CPU. The arithmetic CPU generates a PWM signal and an abnormal display / non-display command signal. The monitoring CPU generates a gate on / off command signal.

In the arithmetic CPU, the torque command value is transmitted to the torque limiter, the torque limiter limits the magnitude of the torque command, and the torque command value is transmitted to the control arithmetic unit. Further, the motor rotation speed is transmitted to the control calculator. The control calculator calculates the torque current value and the exciting current value from the torque command value and the motor speed, transmits the torque current value and the exciting current value to the 2/3 converter, and at the same time, transfers the torque current to the torque current comparator. The exciting current value is transmitted to each exciting current comparator. The 2/3 converter outputs a PWM signal from the torque current value and the exciting current value. The torque current comparator is connected to the monitoring C via DPRAM.
The torque current value calculated by PU is input, and the calculation CPU
The difference between the torque current value calculated in step 1 and the torque current value calculated in the upper monitoring CPU is calculated, and the calculation result is subjected to absolute value processing and output to the monitoring CPU abnormality determiner. The exciting current value calculated by the monitoring CPU is input to the exciting current comparator via the DPRAM, and the difference between the exciting current value calculated by the calculating CPU and the exciting current value calculated by the upper monitoring CPU is calculated. The calculation result is subjected to absolute value processing and output to the monitoring CPU abnormality determiner. The monitoring microcomputer abnormality determiner receives the outputs of the torque current abnormality determiner and the excitation current determiner, determines whether the monitoring CPU is normal or abnormal, and outputs a signal indicating the normality / abnormality of the monitoring CPU as the determination result to the torque limiter. Output to the abnormality display device for the user.

The torque limiter receives a signal indicating normality / abnormality of the monitoring CPU, and when the signal indicates abnormality, narrows the limit value of the torque command value.

Inside the monitoring CPU, the detected current value is transmitted to the motor torque estimating section. Further, the torque command value is transmitted to the torque comparator and the control calculation unit, respectively, and the motor speed is transmitted to the control calculation unit. The control calculation unit calculates the torque current value and the excitation current value from the torque command value and the motor speed, and the calculated calculation result of the torque current value and the excitation current value is DPRAM.
To the arithmetic CPU via. The motor torque estimation unit estimates the actual torque of the motor from the detected current value and transmits the estimated torque value to the torque comparator. The torque comparator receives the torque command value and the actual torque estimated value, compares the difference between the two and a predetermined reference value, and determines whether the arithmetic CPU and the motor drive device are normal or abnormal. Based on the determination result, the arithmetic CPU and the abnormality determiner of the motor drive unit generate a gate on / off command signal.

The motor driving device receives the PWM signal and the gate on / off command signal, and generates torque in the motor. The motor is an induction motor. The inverter is a device that controls the current supplied to the motor by the PWM signal.

The abnormality display device for the user receives a signal indicating the normality / abnormality of the monitoring CPU, and turns off / lights a predetermined LED.

This embodiment has the following effects. First, by notifying the operator of the state of the control device, the operator can make a comprehensive judgment when operating the electric vehicle and avoid stopping at a dangerous place. Secondly, when the motor driving device inside the control device malfunctions, the monitoring device can easily detect the abnormality of the control device and shut off the driving of the motor. Thirdly, when the abnormality determination device of the monitoring device inside the control device malfunctions,
Since the control device throttles the output of the motor, the monitoring device can easily detect the abnormality of the control device. Fourth, an abnormality of the monitoring CPU can be easily detected. Fifth, since the torque calculation of the motor is double calculated by the control device and the monitoring device and the calculation results are compared with each other, inaccurate torque can be suppressed before the motor actually outputs.

[0019]

When the abnormality is only in the monitoring system and there is no abnormality in the drive system, it is possible to move to a safe place or a repairable place by self-propelling.

[Brief description of the drawings]

FIG. 1 is a block diagram of a control device for an electric vehicle according to an embodiment of the present invention.

[Explanation of symbols]

10 ... Control device, 12 ... Motor drive device, 14 ... Abnormality display device to user, 16 ... Operation CPU, 18 ... Monitoring CP
U, 20 ... Gate, 22 ... Einverter, 24 ... Induction motor, 26 ... Rotation speed sensor, 28 ... Torque limiter, 3
0 ... Control calculation unit, 32 ... 2/3 conversion unit, 34 ... Monitoring CP
U abnormality determiner, 36 ... Torque current determiner, 38 ... Excitation current determiner, 40 ... Control calculation unit, 42 ... Motor torque estimation unit, 44 ... Torque comparator, 46 ... Calculation CPU and motor drive unit abnormality determiner , 48 ... DPRAM, 50 ... Current sensor.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Tetsuya Yokoyama 2520 Takaba, Hitachinaka City, Ibaraki Prefecture Hitachi Ltd. Automotive Equipment Division (72) Inventor Hiroyuki Yamada 2477 Takaba, Hitachinaka City, Ibaraki Stock Company In Hitachi Car Engineering (72) Inventor Atsushi Kunimi 2477 Takaba, Hitachinaka City, Ibaraki Prefecture Hitachi Car Engineering Co., Ltd.

Claims (3)

[Claims] 1. An arithmetic unit for driving a motor by performing a motor control calculation based on a torque command value and an input signal value of a motor rotation speed and a command value and / or measured value of at least one of torque and motor current are compared. In a control device for an electric vehicle including a monitoring device for monitoring a motor drive system, the arithmetic device determines an abnormality of the monitoring device from an operation or a calculation result of the monitoring device, and when the determination means detects an abnormality. A control device for an electric vehicle, comprising: means for notifying a driver of an abnormality and means for continuing motor driving. 2. The control device for an electric vehicle according to claim 1, further comprising means for limiting the torque command value to a predetermined value or less when the abnormality determining means detects an abnormality. 3. An electric vehicle according to claim 1, comprising means for monitoring the motor drive system including the arithmetic unit, the gate, the inverter and the motor to determine an abnormality, and means for stopping the driving of the motor when the abnormality is determined. Control device.