Variable-Structure MRAS Speed Identification for Vector Control of Permanent Magnet Synchronous Motor

A novel variable-structure MRAS observer for speed identification was proposed in a sensor-less vector controlled PMSM (permanent magnet synchronous motor) 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.