A Sliding-Mode Position Estimation Method With Chattering Suppression for LCL-Equipped High-Speed Surface-Mounted PMSM Drives

This paper proposes a sliding-mode position estimation method for high-speed surface-mounted permanent magnet synchronous machines with LCL filter. The implementation of the filter aims at smoothing motor current and reducing iron loss caused by harmonic currents. Firstly, discrete-time model LCL-filtered drive system is developed. Based on developed model, observer proposed more robustness against parameter variation to estimate back-EMF, which contains information rotor speed position. Because elimination capacitor voltage sensors, augmented sliding surface designed achieve arbitrary pole placement only output feedback. Besides, considering analog-to-digital scaling error PWM harmonics, reaching law enhanced chattering suppression ability proposed. Compared conventional methods, problem well alleviated thus ripple much reduced. Finally, effectiveness method, even mismatched parameters adopted validated 100 kr/min sampling frequency 20 kHz.