Core Loss Estimation for an Inverter-Fed Induction Motor With More Accurate Realisation of Material Non-Linearity and Impact of Hysteresis Minor Loops

Abstract

The work presents a fast and accurate core loss evaluation method for inverter-fed induction machines. The proposed method takes into account the influence of time variation of magnetic permeability on the eddy current loss. Furthermore, the proposed method presents an accurate approach to precisely evaluate the hysteresis loss. The results obtained from the proposed method are compared with the existing methods for a 1.5kW inverter-driven induction motor. The method shows sufficiently high accuracy with reduced complexity and implementation-time for a wide range of inverter switching frequency and motor's loading.

Magnetic Field-Based Induction Machine Modeling Incorporating Space and Time Harmonic Effects

“…This then followed the nearly sinusoidal variations with the sinusoidal excitations. Furthermore, these additional time-variant non-sinusoidal magnetic fields based on their magnitudes and phase shifts, create additional minor loops, which are influenced by their DC bias levels [26], as shown in Fig. 7.…”

“…7. Determining the minor hysteresis loops requires experimentation that is not feasible at the IM design stages and the mathematical approaches are used for determining the hysteresis losses of the minor loops [26], which are not used to determine the MMF drops at the minor loops. Therefore, the alternative method proposed in this paper is to calculate the frequency of the minor loop (f m ) using its period (T m ), as shown in Fig.…”