A magnetic equivalent circuit approach for predicting PM motor performance

Low power industrial motor electrical drives are dominated by the induction motor, followed by permanent magnet, (PM) motors. This paper presents a magnetic equivalent circuit (MEC) method for predicting the performance of surface mounted PM motors at the design stage. The MEC technique is interesting, as it gives fast (minutes), and acceptably accurate results. It provides a trade off between conventional, empirical methods, having fast simulation times (seconds), limited accuracy and flexibility, and the finite element method, which requires long simulation times (hours) but offers high accuracy and flexibility. Important issues such as element types, reluctance network, saturation, sensitivity to element density, and verification of obtained results are described.