Accurate Performance Prediction of Three-Phase Induction Motor by FEM Using Separate Saturation Curves for Teeth and Yoke

In this paper, the performance analyses of the three phase induction motors have been done by finite element method (FEM) using time harmonic and transient with motion solvers. If there is no saturation in the ferrous portion of the mutual-flux path, the flux wave in the motor approaches a sine-wave shape, but some amount of saturation always exists in a typical three phase induction motor that has the effect of reducing the peak value of the flux wave. To study this phenomena, initially, 60 Hz saturation curves were used for the teeth as well as core yoke and performance analyses of the 2 motors (5 hp 4 P, and 15 hp 4 P) were done by FEM and then in turn, separate AC saturation curves for the teeth and the core yoke derived from the normal DC saturation curve were used, and FEM analyses were done to calculate all the electrical parameters of the motors. In both the cases, computational results are compared with the tested results, and it has been found that the percentage error between computational and tested results is less in case of separate saturation curves for teeth and core yoke compared to the other case.