Voltage and Frequency Regulation of a Stand-Alone Self-Excited Induction Generator

This paper discusses the regulation of the voltage and frequency of a stand-alone self-excited squirrel-cage induction generator (SEIG) connected to an unregulated prime mover by means of a single voltage source inverter (VSI) connected in shunt with the stator of the generator. A battery bank is used at the dc side of the VSI so that it can deal active and reactive power and affect the frequency and magnitude of the generated voltage. The focus of this paper is on the experimental results obtained for a 4-pole 2 HP SEIG with an unregulated prime- mover with a linear torque versus speed characteristic typical of impulse type hydro turbines. It shows that active and reactive power control yields a better voltage and frequency regulation to load variations than reactive power alone.