Inclusion of interbar currents in a network-field coupled time-stepping finite-element model of skewed-rotor induction motors

In order to include the interbar currents of skewed-rotor inductor motors i n finite-element analysis, a three-dimensional (3-D) model is usually neces sary, In this paper a two-dimensional multislice time-stepping finite eleme nt method of skewed-rotor induction motors is presented to solve such compl icated 3-D problems. It is shown that the network of the rotor cage is coup led to finite-element equations so that the interbar currents in the rotor can be taken into account. By arranging the unknowns and mesh-current equat ions ingeniously, the resultant coefficient matrix of the global system equ ations are made symmetrical. Compared with 3-D finite-element methods, the computation time for solving field equations with the proposed method is si gnificantly shorter. The model can be used to estimate the high-order harmo nic stray losses in induction motors. A comparison between computed and tes ted results is also given.