A novel discrete particle swarm optimization algorithm for optimal capacitor placement and sizing

Voltage profiles throughout the electric power system network have to be kept at acceptable levels to ensure network reliability among other issues. Capacitor banks are commonly installed in various parts of the electric grid to maintain voltage levels within proper limits. In general, feeders in distribution systems include the majority of shunt capacitors installations to boost up voltage levels. In this paper, a novel approach is proposed to optimally solve the problem of determining the location and size of shunt capacitors in distribution systems. Traditionally, the problem is usually solved in two steps; first by determining the location of the "needed" bus and then selecting the proper size. The proposed method solves the problems of finding the optimal capacitor size and location simultaneously. Throughout the optimization process, both the capacitor injected reactive power and its location are being treated as discrete variables. The objective function considered in this paper is to minimize the total feeder losses. The proposed algorithm was tested on a standard test system. Results signify the robustness of the proposed algorithm in solving this difficult integer programming problem.