Application of Ultracapacitor, Superconducting Magnetic Energy Storage System Integrated with UPFC to Improve Power Systems Stability

摘要

Power transmission and distribution systems added Flexible AC Transmission Systems (FACTS) devices to improve the performance of the power system with DC link capacitor for temporary energy storage in FACTS. Unified Power Flow Controller (UPFC) with internal DC link class is one of the FACTS technologies. UPFC controls an active and/or reactive power effectively on weak nodes of the transmission power network; however, during large disturbances UPFC performance is not a predictable level of stability. In addition to standalone UPFC, substantial energy storage device is used for the retaining magnitude of system voltage during the huge voltage sag on the transmission power circuit. Chopper act as an interface between standalone UPFC and small-scale substantial energy storage systems. The comparative analysis of superconducting magnetic energy storage (SMES) with UPFC and Ultracapacitor (UC) incorporated in UPFC device is presented in this article. The energy density of SMES is higher than UC, and further exploration has been conducted to verify the performances of the UC system for charging and discharging rate close to SMES system.