Evolutionary fuzzy control of flexible AC transmission system

A fuzzy-controller design by the hybrid of genetic algorithm and particle-swarm optimisation (F-HGAPSO) is employed for a thyristor-controlled series capacitor (TCSC) to improve the transient stability of flexible AC transmission systems (FACTS). According to the variation of rotation speed, a fuzzy controller decides an approximate series capacitance to achieve a better dynamic response of FACTS. To design the fuzzy controller, a new design approach, the F-HGAPSO, is proposed. F-HGAPSO introduces the concept of the maturing phenomenon in nature into the evolution of individuals originally modelled by a genetic algorithm. The maturing phenomenon is mimicked by particle-swarm optimisation, where individuals enhance themselves based on social interactions and their private cognition. Simulations and comparisons with other approaches have demonstrated the effectiveness and efficiency of the proposed F-HGAPSO.