Finite element modeling of the magnetizing inductance of an induction motor as a function of torque

The torque dependency of the magnetizing inductance of an induction motor is studied. A calculation procedure based on accurate finite element (FE) modeling solution of the air-gap flux linkage to obtain the magnetizing inductance of an induction motor at different load conditions is introduced. Two-dimensional nonlinear time stepping FE analysis is used to calculate the instantaneous rotor and stator currents as well as the flux density distribution in the air-gap. The amplitude of the magnetizing current vector is calculated using the sum magnetomotive forces of the rotor and the stator. The magnetizing inductance is calculated from the air-gap flux linkage and the magnetizing current vector. It is shown that the magnetizing inductance of an induction motor decreases as a function of torque.