Transient analysis of induction motor using finite element analysis

This paper presents the analysis of the induction motor behavior during transient periods using the coupled electric circuit with two-dimensional finite element electro-magnetic field analysis. The designed geometric dimension of induction motor is modeled in the finite element domain. In the circuit domain, stator conductors are connected in distributed winding pattern and phase windings are connected in delta. Resistance and inductance values are added in series with each phase winding in the circuit domain to account the 3D parameter values in the 2D modeling [S. Williamson et al., 1990 and Pham, TH et al., 1999]. Each rotor conductor is connected in parallel and a resistance is added in the rotor circuit to account the end-ring resistance. The circuit domain degrees of freedom (DOF) (i.e) the winding current, induced e.m.f. in the windings and supply voltage, are coupled with finite element domain DOF (i.e) magnetic vector potential (MVP). The rotor motion is included in this model to get the real time simulation results. The transient performances are found at the starting of the motor with no load, the operation of the motor with asymmetrical excitation of the stator and turn to turn fault condition. Simulated results for a 3 hp, 4 pole, 50 Hz and 3-phase squirrel cage induction motor is presented.