JPH077806A - Electric vehicle regenerative braking control system - Google Patents

Abstract

(57) [Summary] [Structure] The inverter frequency is multiplied by the coefficient calculated from the coefficient table 7 in which the motor current pattern and the time delay of the electric brake are added by the pattern generated by the regenerative brake pattern generation unit 4. Multiply by and the result is 9
Is multiplied by the actual regenerative braking force by the multiplier 10, and the result 11 is given to the air brake device as a regenerative braking force feedback signal, so that the switching braking force between the regenerative braking and the air brake is obtained in the entire braking force command range. Get smoothly. [Effect] When switching from the regenerative brake to the air brake, a smooth braking force can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a regenerative brake control system for an electric vehicle which supplements a regenerative brake with an air brake.

[0002]

2. Description of the Related Art A conventional control method is to apply a supplementary brake with an air brake in an amount such that the electric braking force of the regenerative brake or the like is insufficient with respect to a command value, and to gradually reduce the motor current at the end of the regenerative brake. Japanese Patent Laid-Open Publication No. 54-13914, which switches to an air brake to smooth the braking force.

[0003]

In the above-mentioned prior art, the actual regenerative braking force of the regenerative brake is applied to the air brake device, and the air brake supplements only the amount that the actual regenerative braking force is insufficient with respect to the command value. Therefore, the action delay time of the air brake changes depending on the amount of shortage with respect to the command value, and a smooth braking force cannot be obtained in the brake command area, and the regenerative brake and the air at the end of the regenerative brake and the end of the regenerative brake cannot be obtained. There was a problem that a shock occurred when switching the brakes.

An object of the present invention is, when applying an actual regenerative braking force to an air brake device, an actual regenerative coefficient for the entire braking force command region consisting of a brake step and a variable load condition in consideration of the action delay of the air brake. An object of the present invention is to provide a control system that multiplies the braking force to achieve smoothness when switching between regenerative braking and air braking.

[0005]

To achieve the above object, the present invention calculates a coefficient based on a regenerative braking pattern, multiplies the actual regenerative braking force, and gives the result to an air brake device.

[0006]

The regenerative braking pattern consisting of the motor current pattern and the inverter frequency is generated by the braking force command consisting of the braking step and the variable load condition. From this regenerative braking pattern, a coefficient that takes into account the action delay time of the air brake is calculated, and by multiplying this coefficient by the actual regenerative braking force, switching between regenerative braking and air braking can be smoothly switched over in the entire braking force command range. Act to replace.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. In FIG. 1, a regenerative braking force command value is given to a regenerative braking pattern generation unit 4 by a circuit 3 that generates a regenerative braking force command by receiving commands from a brake step command device 1 and a variable load command device 2. The VVVF inverter 5 for an electric vehicle is controlled by the pattern generated by the regenerative braking pattern generation unit to control the induction motor 6. In addition, the coefficient calculated from the coefficient table 7 in which the motor current pattern and the time delay of the air brake are taken into consideration by the pattern of the regenerative brake pattern generation unit, and the inverter frequency is multiplied by 8
, The result 9 is multiplied by the actual regenerative braking force by the multiplier 10, and the result 11 is given to the regenerative braking force feedback circuit 12 to be converted into the regenerative braking force and given to the air brake device 13.

The multiplication result 9 of the multiplier 8 by which the actual regenerative braking force is multiplied also includes the rising and falling time coefficients of the regenerative braking.

The relationship between the air brake delay time and the coefficient is as follows:
If the braking force command is large, it takes time for the rising and falling times of the air brake, so the regenerative braking feedback signal is increased and decreased earlier than the actual regenerative braking force. Further, when the braking force command is small, the rising time and the falling time of the air brake do not take much time, so the regenerative braking force feedback signal is increased and decreased later than the actual regenerative braking.

[0010]

According to the present invention, in the entire range of the braking force command value, the actual regenerative braking force is multiplied by a coefficient in consideration of the delay time of the air brake at the regenerative braking rising and the end of the regenerative braking. Since the result is given to the air brake device, a smooth braking force can be obtained when switching from the regenerative brake to the air brake.

[Brief description of drawings]

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

[Explanation of symbols]

7 ... Coefficient table, 8, 10 ... Multiplier, 9 ... Multiplier result of multiplier.

Claims (1)

[Claims] 1. A control device for variable speed control of one or more induction motors for driving a vehicle by an inverter, the function of calculating a coefficient based on the pattern of the regenerative brake at the start of the regenerative brake and at the end of the regenerative brake. And a function of multiplying the coefficient of the calculation result by the actual regenerative braking force and giving the result to the air brake device as the regenerative braking force feedback signal.