JPH09205704A - Control device for automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate abnormal torque generated at a low speed in low torque and make capable safe smooth operation of an automobile, by driving an electric motor with only reference torque, when a reference torque command is sufficiently small namely, at the so-called low torque driving condition, and actuating the motor with a value adding vibration compensation except at low torque driving time. SOLUTION: In an electric motor control means 4, a vehicle model 16 is input, a diameter of a tire 11, a vehicle weight, vehicle inertia equivalent quantity, gear ratio of a reduction gear 10 and rotor inertia of an electric motor 1 are input. These vehicle data are used, a vehicle speed is estimated in a vehicle model speed computing means 17 by a value of a reference torque command. In a compensation torque computing means 14, a difference between the estimated speed and an actual rotational speed of the electric motor 1 is calculated, calculation having a prescribed transmission coefficient is performed, vibration compensation torque is calculated. The sum of this value and the reference torque value is taken, a power converter 2 is controlled. In this way, an automobile can be safely and smoothly controlled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle control device,
In particular, the present invention relates to a control device for an electric vehicle, and particularly to a control device for an automobile that is suitable for improving drivability.

[0002]

2. Description of the Related Art Conventionally, when an electric motor is driven by a storage battery when driving an electric vehicle, the input voltage of the motor is lowered due to drooping of the storage battery voltage, or the drive torque is lowered, or the drive shaft system is driven by a certain speed range. Vibrations may occur in the car body due to resonance. As a method of suppressing this vibration, there is Japanese Patent Laid-Open No. 7-163011.

[0003]

This method is for suppressing the vibration regardless of the reference torque command obtained from the accelerator, brake or shift position only by detecting the rotational speed of the torque motor and the rotational speed of the engine. When the compensation torque command is calculated and a certain number of revolutions or more is exceeded, vibration is suppressed.

However, it is impossible to suppress the vibration generated at the extremely low rotation speed when the accelerator is pressed from the rollback to move forward. When the control of constant vibration control is operated, it is difficult to match the actual vehicle speed with the vehicle model speed incorporated in the control device due to the load capacity, road surface resistance, air resistance, and tire air pressure. The lower the number, the lower the accuracy of torque or speed detection, and the greater the difference between the actual vehicle speed and the predicted vehicle model speed. As a result, when the low torque command is issued, the ratio of the value of the compensation torque command that tries to suppress the vibration becomes larger than that of the torque command from the accelerator or brake, and the compensating torque calculation for vibration suppression adversely affects the vibration. There is a case that the car cannot be stopped safely and smoothly by amplifying.

[0005]

In order to solve the above-mentioned problems, a first aspect of the present invention comprises an electric motor and a power converter for driving the electric motor according to a torque command, and means for controlling the power converter. Motor controller, means for calculating the speed at which the motor controller detects the rotation speed of the motor to drive the load, means for inputting the torque command of the motor to calculate the load model speed from the load model, the load model speed And a speed of the electric motor based on a difference between the motor and the speed of the electric motor, the electric motor control means for stopping the compensation of the torque command by the compensation torque according to the magnitude of the torque command. The present invention provides a control device for an automobile, which is characterized by including the following. A second aspect of the present invention is an electric power converter for driving the electric motor according to the electric motor and the torque command.
An electric motor control device having a means for controlling the electric power conversion device, a means for the electric motor control device to detect a vehicle speed to calculate an actual vehicle speed, and a load model speed is calculated from a load model by inputting a torque command of the electric motor. Means for calculating the compensation torque based on the difference between the load model speed and the vehicle speed, the motor control device according to the magnitude of the torque command, the torque command according to the compensation torque. SUMMARY OF THE INVENTION An object of the present invention is to provide a control device for an automobile, which is provided with means for stopping the compensation of the above. Thirdly, according to a third aspect of the present invention, an engine for generating a driving force for an automobile, a control device for an internal combustion engine including means for controlling a torque command of the engine, and a vehicle model from which the control device simulates the operation of the automobile are used. A vehicle control device comprising means for calculating a model speed and means for calculating a compensation torque for controlling a torque of the engine based on a difference between the vehicle model speed and a rotation speed of the engine is Accordingly, the present invention provides a control device for an automobile, which is provided with means for stopping the compensation of the torque command by the compensation torque.

The control means uses the torque command of the electric motor as a reference input, and predicts the operation of the vehicle using the vehicle model. The vehicle model uses the sum of the motor inertia and the vehicle inertia converted on the electric motor side as the vehicle model inertia, and predicts and calculates the vehicle speed with respect to the torque command of the electric motor. Next, the difference between the predicted and calculated speed and the actual rotation speed of the electric motor is calculated, a calculation having a predetermined transfer function is performed, and the vibration compensation torque is calculated. This value is summed with the first reference torque command to control the power converter. Actually, in the case of a vehicle, vibration does not occur due to load disturbance or difference in mass at that time, and speeds do not match. Therefore, when the reference torque command is sufficiently small, the motor is driven only by the reference torque during so-called low torque driving, and at other times, the motor is operated with a value including the vibration compensation torque, so that the low speed, The abnormal torque generated by low torque can be eliminated, and safe and smooth operation becomes possible.

For the second object of the present invention, the vehicle speed sensor is used to obtain the actual speed in response to the sensorless detection of the rotational speed of the electric motor used for the first object. On the other hand, the vehicle model is matched with the reference torque obtained from the accelerator, brake, and shift position, the predicted speed is calculated, and the compensation torque for suppressing the vibration is calculated by comparing with the actual vehicle speed. When the reference torque command is sufficiently small, the so-called low torque drive drives the motor only with the reference torque, and at other times, it operates with the value to which the compensation torque is added. Abnormal torque can be eliminated and safe and smooth operation becomes possible.

Further, for the third object of the present invention, a compensation torque component including an error obtained from a vehicle model speed and an actual vehicle speed for a vehicle driven by an engine is not added during low torque driving. Therefore, generation of abnormal torque can be eliminated, and safe and smooth operation can be performed.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below. FIG. 1 shows a block diagram of the electric vehicle of this embodiment. The electric motor 1 for traveling with three-phase connection is driven by being supplied with AC power by the power converter 2. Most electric vehicles are equipped with a DC power supply device, which is representative of the storage battery 3. The power converter 2 receives the DC power supply of the storage battery 3 as an input,
It is converted into AC power by a circuit composed of switching elements represented by transistors. In order to convert into an alternating current, a current sensor 23 for three phases is provided to detect the current flowing through the electric motor 1, and the output of the current sensor 23 is fed back to the electric motor control means 4 so that an alternating current flows. Control P
The WM generator 5 compares the carrier wave and outputs a PWM signal. The switching element is driven by the PWM signal, and an alternating current flows through the electric motor 1 to drive the electric motor 1.
The reference torque command τ _c is calculated by the torque command generating means 13. This changes depending on the amount of depression of the accelerator 6 or the amount of depression of the brake 7 and the shift position 8. Depending on the magnitude of the reference torque command τ _c , the amplitude and frequency of the current of each phase flowing in the electric motor 1 change, and a predetermined output torque can be generated. The electric motor 1 is provided with an encoder 9 for detecting the number of revolutions, which is input to the electric motor control means 4 to detect the number of revolutions of the electric motor 1. The driving force of the electric motor 1 is transmitted to the tire 11 of the electric vehicle via the speed reducer 10 to drive the electric vehicle. Therefore, if the reduction ratio does not change, the vehicle speed can be known by the encoder 9. Generally, a vehicle has a vehicle speed sensor 12 to measure the actual vehicle speed.
Is provided. Therefore, both the encoder 9 and the vehicle speed sensor 12 can detect the vehicle speed. The value from the encoder 9 is input to the torque command generating means 13, the correction torque calculating means 14, and the generally known vector calculating means 15. Further, the electric motor control means 4 includes
The vehicle model 16 is input, and the diameter of the tire 11, vehicle weight, vehicle inertia equivalent weight, gear ratio of the speed reducer 10, electric motor 1
The rotor inertia of has been entered. Using these vehicle data, the vehicle model speed calculation means 17 predicts the vehicle speed based on the value of the reference torque command τ _c . FIG. 3 is a block diagram showing the calculation contents of the vehicle model speed calculation means 17 and the compensation torque calculation means 14 shown in FIG. The model speed calculation means 17 calculates τ _p, which is regarded as the actual torque which is the sum of the reference torque command τ _c calculated from the torque command generation means 13 and the model load torque τ _LM obtained by the compensation torque calculation means 14. , The predicted vehicle model speed ω _R is calculated according to the vehicle model characteristic G _vm (S). The compensation torque calculation means 14 performs a vibration compensation calculation G _w (s) from the difference Δω _M between the predicted vehicle model speed ω _R and the actual vehicle speed ω _V to calculate the compensation torque τ _g . The load torque calculation G _LM (s) is performed using the speed difference Δω _M , and the result is used as the model load torque τ _LM . Since the speed difference Δω _M reflects the influence of the load torque τ _{L when} the vibration component is excluded, it is possible to calculate the model load torque τ _LM by simulating the load torque τ _L by inputting this speed difference Δω _M. it can. The load torque calculation G _LM (s) may be a proportional calculation. The vibration compensation calculation G _w (s) may be a proportional control calculation, and the vehicle model speed ω _R is the vehicle speed ω _V
If it coincides with, it is equivalent to that the vehicle model 16 and the compensation torque calculation means 14 can detect the speed difference Δω _M. A model speed difference Δω _M appears when a change in speed appears differently than expected due to the occurrence of a vibration factor. Here, in order to suppress this deviation, a compensation torque τ _g is generated, and the output torque is adjusted to try to make the speed difference Δω _M zero. For actually exits vibration is obtained by integrating the speed difference [Delta] [omega _M to be the derivative element performs simple proportional calculation the speed difference [Delta] [omega _M, by feedback, to suppress generation of vibration in the initial stage This is effective in suppressing vibration. If the gain of the proportional control is increased, the vibration suppressing effect is increased. However, it is difficult to accurately match the vehicle model speed ω _R and the actual vehicle speed ω _V. Particularly in the low speed / low torque command range, the compensating torque τ _g has a bad influence and is liable to vibrate. Therefore, in this region, the compensation torque τ _g
In order not to use the compensation torque τ _g , the compensation torque τ _g and the reference torque τ _c are read in the portion which plays the role of the switch as shown in FIG. This switch corresponds to the switching means 18 in FIG. The control of this switch opens the switch in a region where the reference torque command τ _c is small, in which it is difficult for passengers of the vehicle to experience vibration. When the vibration reaches the range of the reference torque command τ _c where you can feel it, close the switch. The output after this switch control becomes the torque command τ _M for actually operating the electric motor 1. It is better to actually test and determine the value when the reference torque τ _c becomes less than or equal to which the reference torque τ _c should be released. At this time, the compensation torque τ _g
Order to not do a disassociate the connection frequently, the reference torque command tau _c when connecting to the reference torque command tau _c when detach the provision of the hysteresis differently.

These are the actual vehicle speed ω _V detected by the encoder 9 attached to the electric motor 1. It is also possible to use the vehicle speed sensor 12 for detecting the actual rotation speed of the tire 11 to detect the rotation speed of the electric motor. As shown in FIG. 1, if the converter 19 is used to convert the rotation speed of the electric motor 1 in consideration of the gear ratio of the speed reducer 10 before inputting into the electric motor control means 4, the vibration suppression control is similarly performed. It is possible.

FIG. 2 shows an embodiment in which an engine 21 is used instead of the electric motor 1 to drive an automobile. A device for detecting the number of revolutions of the engine 21 and gear ratio information 22 for transmitting a gear ratio are provided, and the torque command generating means 13 generates a reference torque command τ _c from the state of the accelerator 6, the brake 7, and the shift position 8. On the other hand, the information of the vehicle model 16 is input in advance, and the predicted vehicle speed is obtained by the vehicle model speed calculation 17 based on the reference torque command τ _c and the size of the gear ratio information 22. When this speed does not match the actual vehicle speed, the compensation torque τ _g is generated in the compensation torque calculation 14. The generated compensating torque τ _g is added to the reference torque command τ _c during high torque driving, and the vibration is suppressed when the vibration occurs. At the time of low torque driving, a switching means 18 is provided which functions as a switch so as not to add the compensation torque τ _g to the reference torque τ _c . The switching means 18 functions as a switch that can determine the magnitude of the reference torque command τ _c . As a result, it is possible to eliminate adverse effects when the control for suppressing the vibration is operated.

In this embodiment, when applying the vibration suppression control to the automobile, it is possible to prevent the generation of the abnormal torque due to the inappropriate compensation due to the difference between the vehicle and the vehicle model.

[0013]

According to the control device for an automobile of the present invention, it is difficult to feel the vibration, but on the other hand, the vehicle model does not easily match the actual vehicle, and the compensating torque for suppressing the vibration is not applied at the time of low torque driving. By controlling only with the reference torque command, the vehicle can be controlled safely and smoothly.

[Brief description of drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is a block diagram in which an engine control device and a vibration suppressing device in the case of an engine vehicle are combined.

FIG. 3 is a block diagram for calculating a compensation torque command from a vehicle model and a compensation torque calculation.

FIG. 4 is a block diagram showing a compensation torque switching unit.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Electric motor, 2 ... Electric power converter, 3 ... Storage battery, 4 ... Electric motor control means, 5 ... PWM generator, 6 ... Accelerator, 7 ...
Brake, 8 ... shift position, 9 ... encoder, 1
0 ... reducer, 11 ... tire, 12 ... vehicle speed sensor, 1
3 ... Torque command generation means, 14 ... Compensation torque calculation means,
15 ... Vector computing means, 16 ... Vehicle model, 17 ... Vehicle model speed computing means, 18 ... Switching means, 19 ... Converter, 23 ... Current sensor.

Claims (6)

[Claims] 1. An electric power converter for driving the electric motor according to an electric motor and a torque command, an electric motor controller having means for controlling the electric power converter, and the electric motor controller detecting the rotational speed of the electric motor to load the load. A vehicle having means for calculating a speed for driving a motor, means for calculating a load model speed from a load model by inputting a torque command of the electric motor, and means for calculating a compensation torque based on a difference between the load model speed and the speed of the electric motor 2. The control device for an automobile according to claim 1, wherein the electric motor control device includes means for stopping the compensation of the torque command by the compensation torque according to the magnitude of the torque command. 2. An electric power converter for driving the electric motor according to an electric motor and a torque command, an electric motor controller having means for controlling the electric power converter, and the electric motor controller detecting the number of revolutions of the electric motor to load the load. A vehicle having means for calculating a speed for driving a motor, means for calculating a load model speed from a load model by inputting a torque command of the electric motor, and means for calculating a compensation torque based on a difference between the load model speed and the speed of the electric motor 2. The control device for an automobile according to claim 1, wherein the electric motor control device includes means for adjusting the gain of the compensation torque with respect to the speed difference according to the magnitude of the torque command. 3. An electric power converter for driving the electric motor according to an electric motor and a torque command, an electric motor controller having means for controlling the electric power converter, and the electric motor controller detecting a vehicle speed to detect an actual vehicle. A vehicle control device comprising means for calculating a speed, means for calculating a load model speed from a load model by inputting a torque command of an electric motor, and means for calculating a compensation torque based on a difference between the load model speed and a vehicle speed. The motor control device according to claim 1, further comprising means for stopping the compensation of the torque command by the compensation torque according to the magnitude of the torque command. 4. An electric power converter for driving the electric motor according to an electric motor and a torque command, an electric motor controller having means for controlling the electric power converter, and the electric motor controller detecting a vehicle speed to detect an actual vehicle. A vehicle control apparatus comprising: a means for calculating a speed; a means for calculating a load model speed from a load model by inputting a torque command of an electric motor; and a means for calculating a compensation torque based on a difference between the load model speed and a vehicle speed. The motor control device includes means for adjusting the gain of the compensation torque with respect to the speed difference according to the magnitude of the torque command. 5. An engine for generating a driving force for an automobile, a control device for an internal combustion engine comprising means for controlling a torque command of the engine, and the control device for deriving a vehicle model speed from a vehicle model simulating the operation of the automobile. A vehicle control device comprising means for calculating, a means for calculating a compensation torque for controlling the torque of the engine based on the difference between the vehicle model speed and the rotation speed of the engine, is based on the magnitude of the torque of the engine. A vehicle control device comprising means for stopping the compensation of the torque command by the compensation torque. 6. An engine for generating a driving force for an automobile, a control device for an internal combustion engine comprising means for controlling a torque command for the engine, and the control device for determining a vehicle model speed from a vehicle model simulating the operation of the automobile. In a control device for an automobile, comprising: a means for calculating, a means for calculating a compensation torque for controlling the torque of the engine based on a difference between the vehicle model speed and the rotation speed of the engine, wherein the speed is determined by the magnitude of the torque command. A vehicle control device comprising means for adjusting a gain of a compensation torque with respect to a difference.