Influence of Various Non-Oriented Electrical Steels on Motor Efficiency and Iron Loss in Switched Reluctance Motor

The performance of a conventional 6/4 switched reluctance motor (SRM) has been studied using various non-oriented electrical steels for core material. The motor efficiency exhibited a strong correlation with the high-frequency material iron loss W_10/400 (iron loss at 1.0 T, 400 Hz) through the influence on the motor iron loss although the fundamental frequency of the stator is about 100-200 Hz, while the material flux density B50 (magnetic flux density at 5000 A/m) had little influence on the motor efficiency. This paper also presents the calculation results of the motor iron loss based on FE analysis, which applies different equation forms to calculate the hysteresis loss according to typical flux density waveforms, and the computed iron losses agreed well with the measured losses. Then, it is shown that W_10/400 is related well to the variation of hysteresis loss fraction in the motor iron loss for different materials and that the effect of core material on iron loss at higher frequency can be evaluated by their W_10/400 values.