Fuzzy logic switching of FACTS devices for stability enhancement

This paper presents a new switching control scheme for FACTS devices such as high speed phase shifter, thyristor controlled series capacitor modules, braking resistor, and static var compensator, using a fuzzy logic to enhance overall stability of electric power systems. All the FACTS devices are set on one of the buses including generator terminals in transmission systems. The real power flow at the location of the FACTS devices is utilized to determine the thyristor switching. Because the switching control scheme is simple, it does not require heavy computation on the micro-computer based switching controller. The same fuzzy logic switching control scheme is applied to all of the FACTS devices. Simulation results show the effectiveness of the proposed fuzzy logic switching control scheme.