Fuzzy-DE approach for the optimal placement of FACTS devices to relief congestion in a power system

Congestion in transmission lines is considered as a major problem for the electric power transmission. Flexible AC transmission systems (FACTS) devices play a vital role in eliminating transmission line congestion in deregulated power system, improvement of power transfer capacity of an interconnected power system under different loading conditions, thereby increases the possibilities of better economic operation of power system. In the proposed approach fuzzy membership function is used for the determination of weak nodes of a power system for the placement of SVC as one of the FACTS devices. TCSC is the other type of FACTS devices whose positions are determined by the reactive power flow in lines. Then Differential Evolution (DE) is used for the optimal setting of the power system variables, including FACTS devices. The proposed technique is compared with other methods for weak bus detection using modal analysis and the significance of the use of fuzzy membership is clearly observed from the comparative analysis.