A Heuristic Hybrid Technique for the Optimal Allocation of Capacitors in Unbalanced Multiconverter Distribution Systems

The problem of sizing and location of capacitor banks in unbalanced distribution systems with nonlinear loads is addressed. This problem can be solved by means of genetic algorithm based procedures that have been proven to find good solutions. However, when dealing with multiconverter unbalanced large scale systems, these algorithms may require significant computational effort which will reduce their effectiveness. In this paper a hybrid method, which significantly reduces the computational effort without affecting the level of accuracy is proposed. The hybrid method involves a two step procedure: first a small number of nodes are selected as candidate buses for the capacitor allocation through the application of the inherent structure theory of networks; then, a heuristic procedure based on sequential placement of discrete capacitor units is applied to the selected buses. Numerical examples are presented to demonstrate the efficiency of the proposed procedure.