Adaptive observer for sensorless permanent magnet synchronous machines with online pole placement

This paper presents a rotor speed estimation method applied to Permanent Magnet Synchronous Machines (PMSM) based on an adaptive Luenberger observer. adaptive observer is designed through the PMSM model. An online pole placement algorithm is proposed to improve the observer performance. The Luenberger observer gains are updated in accordance with the rotor speed variation. The design methodology of the pole placement of the observer is discussed. Experimental results are presented to validate the proposed technique.