Differential Evolution algorithm based Weighted Additive FGA approach for optimal power flow using muti-type FACTS devices

This paper proposes a novel approach by combining Differential Evolution (DE) algorithm with Weighted Additive Fuzzy Goal Programming (WAFGP) to solve multi-objective optimal power flow problem using multi-type FACTS devices. The Optimal power flow problem (OFF) is formulated by combining two conflicting objectives; maximize load ability and minimize real power losses of an existing system network within the security margins. Line Stability Index (LSI) is used to determine the critical lines in which the FACTS devices be inserted to enhance the performance of the system. Among the various FACTS controllers, Unified Power Flow Controller (UPFC) and Thyristor Controlled Series Capacitor (TCSC) are chosen and modeled for steady state studies. In this proposed approach, first the load ability and real power losses are optimized individually by optimal placement and control parameter settings of FACTS devices using DE algorithm. Then WAFGP is used to combine this multi-objective OPF (MOPF) problem into single standard nonlinear OPF problem. Finally optimal solution is obtained with the help of DE algorithm. This proposed approach is tested on IEEE 30 bus system and the results are used to validate the performance of the approach.