A utility and accurate electrical loss model and application for induction motors utilizing 2-D finite element analysis

The estimation of electrical losses is a basic requirement for motor design based on efficiency optimization. A utility and accurate electrical loss calculation method for induction motors utilizing 2-D finite element analysis is proposed in this paper. The stator copper losses are directly calculated on the basis of Joule´s Law; the rotor copper losses are expressed as the integration of current density; the Bertotti loss separation model is used to predict the fundamental core loss; the surface core losses and pulsating core losses are calculated according to the FFT of air-gap flux density, while the high-frequency stray copper losses are classified into the rotor copper losses. The influence of magnetic wedge on the motor performance is presented during the method. Three experiments are implemented on 450kW, 710kW and 1250kW motors and the validity of the calculation method is proved. An application of the proposed method is carried out on the machine with sinusoidal windings.