Simultaneous Estimation of Current and Speed of Permanent Magnet Synchronous Motor Based on an Improved Dual Second-Order Observer

Abstract

The third-order state observer implements the decoupled control and the accurate estimation of the d-axis current, q-axis current, and rotor speed of the permanent magnet synchronous motor (PMSM). Its complex calculation, however, is a challenge for most digital controllers in practical applications. The authors proposed an improved dual second-order observer based on the Kalman filter. A 0.88 Nm, 1500 rpm prototype was built. The simulation and experimental results prove the effectiveness and practicability of the proposed method.