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 permanent magnet synchronous motor (PMSM). 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 measured impedance characteristics of the PMSM. In order to verify the accuracy of the proposed model, we compared the equivalent AC resistance and AC inductance of one phase of a counter-rotating PMSM calculated from the proposed analytical method with the 3D finite element analysis (FEA) results. Finally, the Impedance characteristic of the test PMSM calculated using the proposed method is verified by the impedance measurement data, which shows a good agreement. The method proposed in this paper can be used for modeling various high-frequency issues in variable speed drives (VSDs) such as electromagnetic interference (EMI), common-mode bearing currents, and long-cable effects on motor terminals.

Keywords:

High-frequency PMSM modeling , laminated iron magnetic cores , physics-based modeling , Analytical modeling , eddy-currents effect