A Particle Swarm Optimization for Maximum Loadability and Voltage/VAR Control

Abstract

As power system networks are becoming highly stressed due to ever-increasing demand, the maximum loadability is achieving great importance. The maximum loadability is also related to voltage stability and security assessment. In this work, Particle Swarm Optimization (PSO) is presented to obtain maximum loadability. The problem to obtain maximum loadability is expressed as an optimization problem. The maximum loadability at a given bus is obtained by taking real load demand at that bus as variable. The load power factor is maintained corresponding to base case power factor at that bus or to specified value. The maximum loadabilities are obtained for various standard systems namely, 2-Bus, 4-Bus, 6-Bus and 14-Bus system and the obtained results from developed PSO based algorithm are compared with Continuation Power Flow (CPF), a widely accepted exact method. The Voltage/VAR control problem has been attempted using PSO by minimizing the real power losses. Both the continuous (automatic voltage regulation supported PV bus voltages) and the discrete variables (on-load tap changer transformers and shunt capacitors) are used as state variables in voltage/VAR control. The voltage/VAR control problem is solved for various systems namely, 4-Bus, 6-Bus and 14-Bus system.