A Sensorless Control Strategy Based on Improved Flux Observer with Dynamic Flux Limition for Permanent Magnet Synchronous Motor

This paper presents a sensorless control strategy based on Improved flux observer for permanent magnet synchronous motors (PMSMs) to Improve the accuracy of estimated rotor position under the condition of variable flux. Firstly, it is verified that the traditional flux observer cannot change the flux amplitude when the flux varies by simulation, and the estimated angle cannot track the actual angle accurately. Secondly, an improved voltage flux observer is proposed to accurately observe the stator flux by adjusting the flux limitation dynamically. Finally, an experimental platform of sensorless control for IPMSM was built to verify the effectiveness of the new algorithm, and the rotor angle could be estimated under the flux variation conditions such as acceleration/deceleration and abrupt loading/unloading.