A nonlinear voltage driven field approach for the analysis of closed slot induction motors

The paper presents a Finite Element approach for the solution of voltage driven nonlinear electromagnetic field problems under periodic supply conditions. The formulation includes the field and circuit equations using as unknowns the nodal values of magnetic vector potential and the currents in the branches of electric circuits. The problem, linearized by the iterative Fixed Point technique, is solved in the frequency domain. The formulation is applied to the analysis of a closed slot induction motor under short circuit test conditions, considering several values of supply frequency and voltage. The computational results are compared with measurements.