High-Frequency Physics-Based Analytical Modeling of Permanent Magnet Synchronous Motor

In this paper, a physics-based analytical method is proposed in order to model the frequency behavior of laminated iron-core AC motors. The proposed model consists of frequency-dependent lumped circuit parameters representing two parts; Iron core and stator winding. These frequency-dependent components represent the skin effect and proximity effect in conductors and eddy-currents effect in the core. The total parasitic capacitance is considered to be frequency independent and estimated from impedance characteristics. The proposed method can be used in modeling various high-frequency issues such as electromagnetic interference (EMI), common-mode bearing currents, and long cable effects on motor terminals. Equivalent AC resistance and AC inductance of a Permanent Magnet Synchronous Motor (PMSM) calculated with the proposed method is compared with the Finite Element Method (FEM) results and shows a good agreement. Finally, the Impedance characteristic of the PMSM motor calculated using the proposed method is verified by the measurement data.