Analysis of torque and eddy current characteristics for induction motor using equivalent circuit and field parameters

A method for the time-step analysis of single-phase induction motors is proposed. The unknown variables in the differential equations are the currents flowing through the rotor bars. They are coupled with the distributed magnetic flux densities in the air gap instead of the inductance matrix while applying Kirchhofes and Faraday's induction laws. Two patterns for magnetic flux densities are necessary. One is given by an ideal stator winding distribution, whereas the other is produced by currents flowing through a rotor bar with unit magnitude and is calculated using the finite element method (FEM). The formulated set of equations is solved for a simple three-phase and single-phase example model and the resultant speed torque curve is shown in this paper.