Speed control of PMSM based on an improved equivalent input disturbance estimator

This paper presents an improved equivalent input disturbance estimator to solve the influence of unmeasured disturbance on permanent magnet synchronous motors (PMSM). Fuzzy PID controller is designed and the estimator combines state observer and low-pass filter to equivalent the real unknown disturbance to the input disturbance of plant. The controller and estimator satisfy the separation principle by using the estimator presented. The simulation results of a PMSM system with equivalent input disturbance estimator demonstrate that the estimate of unknown disturbance is valid and the performance of PMSM is also improvement.