MODELING AND ANALYSIS OF A TR CTION CONTROL SYSTEM FOR TWO INDEPENDENT WHEEL DRIVES-ELECTRIC VEHICLE

Abstract

This paper presents a detailed dynamic model of an

electric vehicle with two independent wheel drives and an

improved traction control system. The present research

demonstrates a model and analysis of a traction control system

for two independent wheels drives electric vehicles. An

electrical differential was implemented assuring that in a

straight trajectory, the two rear wheels run exactly at the same

speed (for a steering angle equals zero) and for the same road

conditions under the left and right side of wheels. However, an

electrical differential with the control strategy is established due

to:

1- When the vehicle turns right and left, the references for the

rear speeds are selected according to the steering angle, to

ensure that during turning the wheels will maintain the relative

speeds imposed by the trajectory geometry.

2- When the motor is tested with two different subclasses of

four quadrant of DC/DC chopper voltage to study the method

for developing energy saving.

With the information about the real speed of the vehicle, on left

and right sides, the control algorithm changes the generated

torques in each wheel drive, in order to produce the same

traction force applied to the road surface.