Hybrid PI-fuzzy controller based static var compensator for voltage regulation under uncertain load conditions

This paper presents the voltage regulation strategy under uncertain load condition,using hybrid pi-fuzzy controller based static var compensator. the static var compensator could obtain the appropriate value of injected susceptance by triggering the thyristor of the svc with proper firing angle. this proper firing angle could be acquired by hybrid pi-fuzzy control strategy. a series of connected simple pi controller and fuzzy logic controller formed the hybrid pifuzzy controller. the simulations showed that this control strategy is capable to regulate the voltage under uncertain load. the proposed controller resulted in an average settling time of 0.1346 seconds for the first case and 0.1469 seconds for the second case. the conventional pi controller resulted in an average settling time of 0.188 seconds for the first case and 0.1702 seconds for the second case.