An Improved Composite Position Controller based on Discrete-Time Terminal Sliding Mode Control for PMSM Servo System

This paper proposes an improved composite position controller of the permanent magnet synchronous motor (PMSM) for servo application. The proposed position controller consists of a feedforward controller and a discrete-time terminal sliding mode controller (TSMC) with a disturbance observer (DOB). The feedforward controller aims at improving the dynamic performance by the prior knowledge. Then the TSMC with the DOB is designed to achieve fast tracking performance and good disturbance attenuation. The effectiveness of the proposed method is validated by the simulation.