Dynamic modeling of universal motors

Abstract

A general time-stepping approach is presented to solve coupled field-circuit-motion problems for universal motors. Circuit equations are used to describe the dynamic connections of field and armature coils, to include the end leakage inductance and the voltage drop across brushes, and to support a voltage source with arbitrary waveforms. In addition, the effects of the coils undergoing commutation have been considered by having them removed temporarily from the main winding and excited by a controlled current source.