Anti-skid control system for an electrically operated vehicle

摘要

The present invention is directed to an anti-skid control system for controlling a braking force applied to road wheels including driven wheels of an electrically operated vehicle which has an electrical motor for driving the driven wheels. A hydraulic braking pressure is supplied to each wheel brake cylinder through an actuator. The actuator is controlled by a braking force controller into which output signals of wheel speed sensors are fed. A band-pass filter is provided for passing the wheel speeds of the driven wheels having an oscillation property within a predetermined band of frequencies, out of the wheel speeds detected by the wheel speed sensors. And, a coefficient of friction of a road is estimated to be relatively low when the output of the band-pass filter is in a predetermined range of frequencies. The hydraulic braking pressure in each wheel brake cylinder is controlled by the braking force controller in accordance with the estimated coefficient of friction and in response to the wheel speeds detected by the wheel speed sensors, thereby to control the braking force applied to each road wheel.