Modeling and Calculation of Iron Loss With Accurate Variable Coefficients Considering Multiple Factors

The iron loss generation mechanism of permanent magnet synchronous motor (PMSM) is complex and influenced by various physical factors. The classical constant-coefficient iron loss model cannot accurately calculate the iron loss of the motor. To improve the accuracy and applicability of the iron loss model, based on iron loss data from silicon steel sheet ring specimen, this paper proposes a variable-coefficient iron loss model. The model comprehensively considers factors such as magnetic flux density, frequency of the magnetic field, skin effect, nonlinearity permeability and temperature. The stator and rotor iron losses of an 8-pole, 48-slot interior permanent magnet synchronous motor (IPMSM) are calculated based on the variable-coefficient iron loss model constructed in this paper, and the magneto-thermal coupling model is established to obtain the temperature distribution of the motor. The comparison between the simulated temperature rise and the experimental temperature rise shows that the error between the motor simulation temperature rise, calculated based on the iron loss model data, and the experimental temperature rise data is less than 5%, which verifies the accuracy of the proposed iron loss model.