Use of a three-phase oscillator model for the compact representation of synchronous generators

A recently suggested three-phase oscillator model system is developed further. The resulted model, although it is relatively simple and merely of a seventh order, represents fairly accurately the features and the dynamic behavior of a regulated synchronous generator (the simulated results on a digital computer are compared to measurements on a 2.2-kVA generator system). The model, in spite of its demonstrated simplicity, embraces a fully three-phase dynamics which includes variations directly at the line frequency. The three-phase oscillator signals represent in the model the components of a rotating magnetomotive force. Magnetomotive forces are regarded as the main variables, since the regulation in an experimental generator system, which is employed for comparison, is achieved by controlling the rotor current via a current source.