Particle Swarm Optimization using Adaptive Inertia Weight for Optimal Capacitor Bank Placement in Radial Distribution Networks

The steady increase in energy demand results in under-voltage problems and an increase in the active power losses in electrical distribution networks. The optimal placement of capacitor banks in distribution systems is essential for enhancing the voltage profile and reducing power losses. This paper proposes a modified particle swarm optimization (PSO) algorithm using an adaptive inertia constant to expand the search space and determine the optimal locations and sizes of capacitor banks. Two loss sensitivity indices (LSI) were applied to identify candidate buses. This methodology was applied to the IEEE 33-bus radial distribution system considering two scenarios: one with fixed capacitors (Case 1) and the other with switched capacitors (Case 2). The results demonstrate that the proposed algorithm effectively reduces system losses by 31.30% and 31.38% in Cases 1 and 2, respectively. In addition, in both cases, the voltage profiles were improved and maintained within allowable limits. Therefore, the proposed methodology is expected to work well in larger electrical distribution networks.