Enhanced Genetic Algorithm Approach for Security Constrained Optimal Power Flow Including FACTS Devices

Abstract

� Abstract—This paper presents a genetic algorithm based approach for solving security constrained optimal power flow problem (SCOPF) including FACTS devices. The optimal location of FACTS devices are identified using an index called overload index and the optimal values are obtained using an enhanced genetic algorithm. The optimal allocation by the proposed method optimizes the investment, taking into account its effects on security in terms of the alleviation of line overloads. The proposed approach has been tested on IEEE-30 bus system to show the effectiveness of the proposed algorithm for solving the SCOPF problem. Keywords—Optimal Power Flow, Genetic Algorithm, Flexible AC transmission system (FACTS) devices, Severity Index (SI), Security Enhancement, Thyristor controlled series capacitor (TCSC). preventive approach for security enhancement, the post contingency state corrective action can also be used for security enhancement. The resulting stage has the same security level as the usual security - constrained optimal power flow case with lower operating cost. The power electronics-based FACTS devices can also be employed for corrective action due to its high speed of response. Thyristor controlled series capacitor (TCSC) is one such device which offers smooth and flexible control of the line impedance, with much faster response compared to the traditional control devices. TCSC can be used effectively in maintaining system security in case of a contingency; by eliminating or alleviating overloads along the selected network branches. It is important to ascertain the location for the placement of these devices due to their considerable costs. In this paper, the location of the TCSC is