Optimal Location of UPFC and Comparative Analysis of Maximum Loadability with FACTS in Competitive Electricity Markets

Flexible ac transmission systems (FACTS) controllers, which can effectively enhance the loadability of the network by controlling the power flows, must be placed optimally due to their high cost. This paper proposes a mixed integer based non-linear programming approach for optimal location of UPFC for system loadability enhancement in competitive electricity markets. The method accounts for ac load flow equations with constraints on generation, line flows and FACTS controller parameters. New secure bilateral transaction matrix based on AC distribution factors has also been proposed. The system loadability has been determined in a hybrid electricity market model incorporating bilateral transaction matrix in the optimal power flow model. The results obtained with UPFC have been compared with the other optimally placed FACTS controllers like TCPAR and TCSC. The proposed technique has been demonstrated on IEEE 24 bus reliability test system.