Voltage control of induction generator powered distributed system using a new reactive power compensator SVC-MERS

Distributed power system has attracted great interest in terms of renewable energy use and new generation technology. Induction generator is one of the most widely used energy conversion means due to its low cost, robustness and simple control. This paper proposes a distributed system which is powered by squirrel cage induction generators (SCIG). Different from the synchronous generator, SCIG has to get exciting current from outer device at normal operation. Furthermore, voltage instability problem exists at the load change when it is excited with fixed capacitor bank. In order to solve this problem, this paper proposes a new technology named Static VAR Compensation Magnetic Energy Recovery Switch (SVC-MERS) for the induction generators. The SVC-MERS aims to stabilize the generator voltage by providing continues variable reactive power. The operation principle is further developed in order to get a broader operating range. It is confirmed by simulation results. Then, voltage control of induction generator is experimented and the SVC-MERS is proved to stabilize the generator voltage with quick response. Compared to the STATCOM, the SVC-MERS has advantage in line frequency switching and small dc-capacitor.