Modeling of Saturation Due to Main and Leakage Flux Interaction in Induction Machines

Saturation due to main flux and rotor leakage flux interaction appears in induction machines, particularly if rotor slots are skewed or closed. Conventional saturation models used in connection with dynamic equivalent-circuit models do not take this phenomenon into account. In this paper, explicit functions for modeling this mutual saturation are proposed. These functions are physically reasonable and are easy to fit, and the number of their parameters is small. The proposed functions can be used in real-time applications and in computer simulations if high accuracy and physical consistency are preferable. The model fits well to the data obtained from finite-element analysis or experimental data of a 2.2-kW motor. The model predicts the stator current with good accuracy both in steady state and in transients.