Compensation Strategy of the Numerical Analysis in Frequency Domain on Induction Motor Considering Magnetic Flux Saturation

Numerical analysis in frequency-domain guarantees convincing accuracy by reflecting non-linearity of material without massive computation time, combining advantages of the equivalent circuit method and numerical analysis method. However, at highly magnetic saturated regions where non-linearity of the material is severe, error in torque calculation is evident, as parameters in frequency domain are presumed to be in a sinusoidal condition. Many researchers have been suggested a compensating method by creating fictious material with logically modified B-H curve. Nevertheless, the error between the results of the numerical analysis in frequency-domain and time-domain analysis is not small enough to estimate motor characteristic. Therefore, the compensation method for improving accuracy on the estimation of induction motor characteristics is proposed in this paper. The numerical analysis based on finite-element method in frequency domain has been conducted using the proposed fictious material and the result is compared to those of the conventional methods and time-domain analysis to validate its improvement on accuracy.