Torque optimization analysis with magnetic saturation models for induction machines

A new model based on MT synchronous rotating frame of induction machines with magnetic saturation is developed. In this model, it is assumed that the saturated area mainly on the M-axis and the undersaturated magnetic path is kept when stator and rotor currents make balanced MMF. This assumption is proved by finite element analysis (FEA). The result is the suitable condition of the assumption when neglecting the “cross saturation” in the model. By applying this nonlinear model, the torque per ampere output was analyzed. The results show that the peak torque per ampere is available by selecting optimum rotor flux other than constant flux controlling strategy