A Graph Theoretic Approach Based Capacitor Placement in Unbalanced Distribution System

This paper presents a graph theoretic centrality index based methodology to solve capacitor placement problem for unbalanced distribution system (UDS). The aim of this paper is to present a new approach for optimal placement of capacitor bank (CB), to minimize system loss and maximize the net saving for UDS. Particle Swarm Optimization is used to determine the optimal size of CB. The objective function for optimal sizing of CB consists of three terms - cost associated with CB purchase and installation, and cost of energy loss. The proposed method was tested on benchmark networks (IEEE 13-bus, and 25 bus systems) and compared with power loss index (PLI) based method. The results obtained from both methods are comparatively analysed and discussed. The comparison of power loss reduction, status of voltage profile, and net saving are presented for both approaches for the test systems.