摘要

Based on the nonlinear characteristics of permanent magnet synchronous motor (PMSM), a nonlinear speed and direct torque control (DTC) using sliding mode backstepping method for PMSM is presented in this paper. The sliding mode speed controller is implemented with exponential reaching law to improve the robustness of the system, and further a step-by-step recursive design for backstepping torque and flux controllers is presented. The system stability with proposed scheme is mathematically proved using Lyapunov stability criteria. At the same time, the load torque is observed with the extended state observer (ESO), and is fed-forward to the controller for rejecting the load disturbance and to mitigate the chattering affect due to the sliding mode controller. Finally, simulation test results are demonstrated to support the effectiveness and feasibility of the proposed strategy.