Magnetic Circuits Within Electric Circuits: Critical Review of Existing Methods and New Mutator Implementations

In this paper, a critical review of existing methods to couple magnetic circuits to electric circuits is provided and explained using a two-port element called mutator. In order to couple magnetic circuits in electromagnetic transients-type programs, a new implementation of mutators is described, which uses the commonly available coupled series R-L branches. The practical case of a single-phase two-winding transformer is studied, and the results show that the new method is equivalent to the dual (inductive) model. However, it is concluded that the new method is more interesting than duality to couple large 3-D topological models (transformers, lines, motors, etc.), because it avoids difficulties of duality associated with nonplanar magnetic circuits.