Nonlinear sliding mode observer based on back EMF of PMSM

Since Permanent Magnet Synchronous Motors (PMSM) came in use in industry, major research (Furuhashi, 1992), (Chen et al., 2000), 436 (Misawa, 1987), (Fakham et al., 2004), (Fakham et al., 2005) was done to eliminate sensors that are needed for proper control. Tllis leads the whole system (motor and control) to be cheaper and more robust to noises and other “electrical pollution”. Tltis paper proposes the observability analysis of PMSM as a high order nOlllillear system. Also it presents a design of a sliding mode observer based 011 back EMF which has a good robustness against the variation of electrical parameters of the motor. The effect of the variations of motor parameters such as stator resistance and stator inductance has been studied too. The simulation and experimental results are shown to demonstrate the effectiveness of the approach.