µ-Synthesis Robust Torque Coordinated Control of Two-Wheel Driving Electric Vehicles

Based on analyzing the driving system of motors in series, it indicates that the system simplifies the structure and realizes the effective self-action differential when the electric vehicle(EV) runs on the level road without any variety or at low velocity. When the EV runs on the variational road, especially the friction force is variant, the EV is unstable according to the character of the permanent-magnet brushless DC motors (PMBDCMs). In this paper, the structure was improved and a mu-synthesis robust controller of a two-wheel steering vehicle is designed with the optimized weighting functions to attenuate the external disturbances while the yaw rate is chosen as the only feedback signal. The experimental result shows that the series connected two-wheel driving EV via mu-synthesis robust controller has better maneuverability and stronger ability to resist disturbances; it is not sensitive to the variations in vehicle parameters. The propose system improve the EV´s maneuverability and stabilization.