Research on Direct Torque Control of Permanent Magnet Synchronous Motor Drive Based on Extended State Flux Linkages Observer

This paper describes an investigation of direct torque control (DTC) for permanent magnet synchronous motor (PMSM). The drawback that the flux observation accuracy was influenced by uncertain parameters in tradition flux model could be overcame by using observer method, and the flux is estimated accurately under whole speed range. This paper designs the nonlinear extended state observer and uses it in the stator magnet flux linkage estimation. The simulation results indicate that observed flux with the uncertain stator resistance values is more precise and robust than conventional flux model.