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Permanent magnet synchronous machines and induction motors are often required to operate on‐line starting or inverter‐fed systems, which results in nonsinusoidal stator currents. These, in turn, give rise to undesirable harmonics and power losses which degrade motor performance. In this paper a time‐domain analysis is presented for evaluating the magnetic field distribution in the two‐dimensional cross section of the machine under load conditions. The analysis is applied to a permanent magnet synchronous machine under locked rotor conditions. Although for purposes of this analysis, the iron permeability has been assumed a constant, the method can be easily extended to include iron saturation.

Design of modern electrical machinery to operate at high power densities and optimal efficiency requires accurate performance prediction. To accomplish this objective, magnetic field analysis must be performed taking full account of three‐dimensional effects and iron saturation. In this paper, a three‐dimensional magnetostatic analysis using a hybrid finite‐element formulation is presented. The method employs a combined vector and scalar formulation for representing the magnetic field. The analysis developed in the paper is applied to a permanent‐magnet synchronous machine for evaluating the field distribution on no‐load, in the body of the machine and the end region. Since the operating regime of this particular machine is in the unsaturated region, it was sufficient to implement a finite permeability case. The method described could be easily extended for the full‐load case and the nonlinear algorithm implemented.