Sensorless Control Method for High-Speed Permanent Magnet Motors Based on Reduced-Order Observers

Abstract:

To address the challenges of the non-position sensing algorithm in response speed， dynamic stability and calculation time of high-speed permanent magnet synchronous motor under low speed conditions， a new high-frequency injection down-order estimation method is proposed. By reducing the integration link of the position observer and the use of the bandpass filter， the phase delay of the rotor is reduced， and the dynamic response and algorithm efficiency of the system are improved. Moreover， the steady-state error is eliminated by introducing the feedforward compensation of the rotor’s phase angle position， realizing error-free tracking. The experimental results demonstrate that the proposed method achieved a rotor position estimation error of 5.7 ° under steady-state conditions at 300 r·min^-1， which is only ?31 % of that of conventional methods. Additionally， the settling time during dynamic conditions is reduced by ?30 %?， and the computational time of the algorithm decreases by ?18 %?. The proposed method exhibites advantages such as ?fast response， stable dynamics， and reduces computational load， meeting the requirements for rapid and reliable startup in high-speed motor systems.