A New Observer of Stator Flux Linkage for Permanent Magnet Synchronous Motor Based on Kalman Filter

A new observer of stator flux linkage for permanent magnet synchronous motor new observer of stator flux linkage for permanent magnet synchronous motor (PMSM) based on Kalman filter theory is proposed. The design principle and realized means of Kalman filter are explained in detail. The observer has the following attractive features: 1) it can be applied to both of salient-pole and nonsalient-pole PMSMs; 2) it can eliminate the defects of conventional pure integrator such as dc drift and error accumulation; 3) it is robust to all kinds of noise; 4) it doesn´t need measure permanent stator flux linkage in advance; and 5) it adopts a set of recursive arithmetic for computer so the memory storage and computing time can be decreased dramatically. Finally the observer is applied to a control system of direct torque control (DTC) for a nonsalient-pole PMSM and the results of simulation show that the new method has better observation effect for stator flux linkage as well as performance of control system.