ABSTRACT
In a Distributed Drive Electric Vehicle (DDEV) equipped with four motors, unequal driving torques on each wheel of the front axle can be output, by which the differential steering torque can be generated. An integral anti-windup PI control algorithm is designed to realize the Differential Drive Assisted Steer (DDAS) and prevent motor torque saturation. Meanwhile, aiming at improving returnability, a return-to-center control algorithm is developed. As the DDAS generates not only steering assisted torque but also extra yaw moment, the integrated control system which combines the differential drive assisted steer and Torque Vectoring Control (TVC) is developed to improve vehicle yaw motion. Field test results indicated that steering portability and returnability can be improved by the proposed assisted steering algorithm; the integrated control system can reduce operation burden and improve vehicle maneuverability.
