Optimal location and parameter settings of UPFC using ACO for enhancing power system security under single contingencies

Abstract

Optimal setting and location of Flexible AC Transmission Systems (FACTS) devices are widely used in enhancing power system security. The most effective FACTS device is Unified Power Flow Controller (UPFC) which has both series and shunt compensation. The effectiveness of FACTS device over the mitigation of security issues depends on its location and its parameter settings. Hence, this paper presents Ant Colony Optimization (ACO) methodology to optimally locate UPFC to enhance power system security under single contingencies (N-1 Contingency). The simulation is carried out on IEEE 6 bus and IEEE 14 bus test systems considering line over loads and bus voltage violations for ensuring system security. This approach is twofold. Initially, an N-1 contingency test is performed based on severity ranking is done then UPFC is placed optimally using ACO algorithm to mitigate the severity. Further to validate the proposed approach the results are compared with the conventional Non Linear Programming - Interior Point (NLP-IP) technique.