An improved particle swarm optimization algorithm for optimal placement and sizing of STATCOM

The major concern of power utilities is to maintain, in all situations, the supply of electrical power to all its customers without any failure. However, because of a recent phenomenon such as demand power increase, insufficient power generation and other economical and environmental factors, most power system utilities operate with its equipment very close to their limits. This situation implies that events such as voltage instability and voltage collapse become more likely to occur. The static synchronous compensator, a shunt-connected Flexible AC Transmission Systems device capable of regulating the voltage level, is an important tool in order to prevent these occurrences from happening. In this paper, an approach to the problem of where these devices have to be inserted and what size should they have in order to enhance the voltage stability margin to a specified level is introduced in the form of metaheuristic approach. The approach was developed using the continuation power flow method to calculate the point of maximum loadability of the power system and using the particle swarm optimization concept to find the optimal combination of locations and sizes of a group of static synchronous compensator units. This is a known approach to the problem, but a new design of the objective function, which seeks to attain a pre-specified desired voltage stability margin, instead of maximizing it, is presented as an original contribution of the paper. Copyright © 2015 John Wiley & Sons, Ltd.