Equivalent circuits for transformers and machines including non-linear effects

A simple method is described whereby appropriate equivalent circuits may be developed for transformers and rotating machines. Sections of the magnetic system are represented by analogous electric elements in the equivalent circuit and in this way the effects of magnetic non-linearity are preserved. The assumptions made in the method are those usually made by the designer in reducing the magnetic field of the apparatus to a magnetic circuit. The method is demonstrated by developing equivalent circuits for 3-phase core-type transformers, polyphase induction and commutator machines and synchronous machines of both the round-rotor and the salient-pole type.