Estimation of core loss in a switched reluctance motor based on actual flux variations

Accurate calculation or the core loss in a motor is essential for computing the actual efficiency. In a switched reluctance motor (SRM), the non-sinusoidal flux waveform with different frequencies of flux reversals in various parts of the motor makes the core loss calculation difficult. The conventional method for calculation of the core loss is based on the stator pole flux density variation in the triangular fashion with the peak flux density at the rotor position corresponding to the conduction angle from the unaligned position, which will not give accurate results. In this paper, an accurate method for the calculation of the core loss based on actual flux waveforms in various parts of the SRM is presented. The proposed method is validated using the FE analysis. The difference in the core loss estimated using the proposed and the conventional methods with the one obtained using the FE analysis is 4.89 % and 17.23 % respectively.