Improved and Time-Efficient Harmonic Model of Induction Motor Considering Iron Nonlinearity

Abstract

Comprehensive implementation of magnetic nonlinearity with Fourier-based modeling poses critical challenges of convergence, rigging, and time and space complexities. The proposed model puts forward an alternate analytical method to consider the magnetic nonlinearities of all the motor segments. The formulation employed to develop the model attempts the implications of saturation and magnetic nonlinearities to incorporate them in the form of geometry modulation. The implementation does not correspond to any domain extension or magnetic vector-potential dependent term and, hence, does not endure the rank deficiency with infinitely permeable iron. The estimation accuracy of the model is demonstrated by evaluating the performance of a four-pole medium-scale laboratory prototype of a squirrel cage induction motor for a wide range of magnetic loading. Comparing the results obtained with the proposed method, finite element analysis, and measurements, it is observed that the proposed formulation enables the subdomain to achieve reasonable accuracy.