A Novel Approach for Circuit-Field-Coupled Time-Stepping Electromagnetic Analysis of Saturated Interior PM Motors

This paper presents a novel approach for circuit-field-coupled time-stepping electromagnetic analysis of a saturated interior permanent-magnet (IPM) synchronous motor. To predict the drive performance quickly, the proposed approach consists of a dynamic simulator based on a novel nonlinear model of the d-q flux linkages of the IPM motor. The model can take into account not only the magnetic saturation but also the harmonics of inductance distributions and EMF waveforms. The validity of the model is verified from suitable simulation results of the instantaneous current and torque waveforms of the IPM motor. The proposed analysis realizes a dramatic reduction in the computation time compared to circuit-field-coupled time-stepping finite-element analysis, keeping analytical accuracy. A 10-kW 15 000-r/min prototype driven by a pulsewidth-modulation inverter was used for laboratory testing to verify the analysis. The experimental results showed quite reasonable agreement with the predicted instantaneous current.