Position estimation of surface permanent-magnet synchronous motors based on a new reduced-order model with guaranteed global stability

This paper proposes a new reduced-order model for a surface permanent-magnet synchronous motor (SPMSM). A position estimator with global stability is then designed based on the proposed model. Design criteria for stability, dynamic and tracking performances are clearly given. The importance of global stability is emphasized by comparison with the design with only local stability. Theoretical results are verified by simulation and experiment.