Application of Fuzzy Logic - Particle Swarm Optimization for Reactive - Power Compensation of Radial Distribution Feeders

Electric distribution systems are becoming large and complex leading to higher system losses and poor voltage regulation. This has stressed the need for an efficient and effective distribution network The objective of this work is to determine optimal location and size of the capacitor to be placed in radial distribution feeders to improve the voltage profile and to reduce the energy loss. This problem of capacitor placement is solved using fuzzy expert system and sizing is solved using particle swarm optimization method.

Firstly, an efficient load flow solution for the radial feeder is obtained by forward sweeping algorithm. Voltage and real power loss index of distribution system nodes are modeled by fuzzy membership function. Then, a fuzzy inference system containing a set of heuristic rules is designed to determine candidate nodes suitable for capacitor placement in the distribution system. Capacitors are placed on the nodes with highest sensitivity index. The sizing is found by using Particle Swarm Optimization (PSO). The proposed method is tested on IEEE-11kV, 12 bus system (without lateral) and an existing 15 bus system (with lateral) in India.