Variable-structure MRAS Speed Identification for Permanent Magnet Synchronous Motor

This paper proposes a novel variable-structure model reference adaptive system(MRAS) observers for speed identification in a sensor-less vector controlled permanent magnet synchronous motor(PMSM) drive.This strategy selects PMSM itself as the reference model and its current model as the adjustable model by combining MRAS with variable-structure control to formulate a slide mode surface according to two model output errors.Theoretical analysis and simulation results show that the proposed strategy has stronger robustness and satisfactory performance.