Inductance Calculation of Flux Concentrating Permanent Magnet Motor through Nonlinear Magnetic Equivalent Circuit

Abstract

In order to design a permanent magnet synchronous motor (PMSM), the inductance must be computed. In this paper, the flux concentrating PMSM (FCPMSM) is introduced. Calculating the inductance is difficult because of the complex structure of the rotor. Because the rib and the bridge consist of an iron core, they have nonlinear characteristics. In order to obtain the effective value of the inductance, nonlinear characteristics must be considered in a magnetic equivalent circuit (MEC). In this paper, to calculate the inductance of an FCPMSM, the relative permeance of the rotor was analyzed. Then, the dq-axis MEC, including the nonlinear magnetic reluctance, was created using the flux line. Finally, we verified the validity of the proposed inductance calculation method by comparing the results between the finite-element method and the proposed method.