Voltage regulation scheme for distribution lines is one of the key technologies to realize an independent small-scale electric power network consisting of many distributed generators that convert from renewable energy into electric energy. In this study, a small independent electric power system model has been made from the actual island-power system, and three types of FACTS devices, Static Synchronous Compensator(STATCOM), Static Synchronous Series Compensator(SSSC) and Unified Power Flow Controller(UPFC) are analyzed by comparison of required minimum capacity of the inverters in a residential distribution network with a large peneration of photovoltaic generations. From a comparison of the required minimum capacity in radial distribution network, UPFC needs less capacity than STATCOM and SSSC. In this simulation, if can be said that injecting AC voltage via series transformer is effective for the voltage control of the distribution network.
Photo Voltaic Generation, Flexible AC Transmission System, Unified Power Flow Controller, Voltage Regulation, Independent Power System