A High Precision Observer Using a Full-Range Harmonics Suppression Scheme for High-Speed Permanent Magnet Synchronous Motor

The stator currents of the high-speed permanent magnet synchronous motor contain both low-frequency and high-frequency harmonic components, which lead to errors in the estimation of the back electromotive force and affect the performance of the observers. Traditional harmonic filtering solutions mostly focus on low-frequency harmonics, but for high-speed motors with low inductance, the hazards of high-frequency harmonics cannot be ignored. This paper proposes a full-range harmonics suppression scheme to improve the accuracy of the observer. The LC filters are applied to filter out high-frequency harmonics of the stator currents and the notch filters are designed to eliminate the system resonance peak. The comb filters are used to suppress the low-frequency harmonics in the back electromotive force at a low computational cost. The proposed scheme is simulated and verified in Simulink/MATLAB.