Development of a model for representing dynamic behaviour of synchronous motor variable speed drives

The paper introduces a compact method for representing synchronous motors connected to a source of variable frequency. The model is based on a three-phase sinusoidal oscillator that represents the components of the magnetomotive force. The whole model is of seventh order and it accurately represents the dynamic behaviour of the motors. Even simulated dynamic behaviour, in which rapid frequency modulation of the voltage source is involved, agrees well with that obtained by experimenting with a laboratory system. One of the advantages of the model is its applicability for permanent magnet motors and permanent magnet brushless DC motors