Torque Control for Electric Drive System Used in Electric Vehicle in the Presence of Permanent Magnet Demagnetization Faults

The performance of conventional torque control for PMSM drive used in electric vehicles (EVs) from the viewpoint of permanent magnet (PM) demagnetization faults has not been satisfactory. Therefore, a combination method based on sliding-mode observer and active disturbance rejection control is presented. First, the model of the PMSM system with PM demagnetization faults is constructed. Then, a sliding-mode observer is designed based on a minimum extended flux linkage to estimate the torque and the PM flux linkages of the system. A current controller is presented based on active disturbance rejection control approach to reject the PM demagnetization faults. The method is useful to improve the control performance of the PMSM drive system. And the system is robust to system parameters variations. Finally, an RT-LAB real-time simulation is used to build a simulation model of hardware-in-the-loop based on the experimentally validated model that is derived from the actual development process for an electric bus. The simulation and experimental results demonstrate the effectiveness of the method.