Capacitor placement in unbalanced distribution networks to minimize reactive and unbalance power losses

Abstract

In this paper, the optimal placement and sizing of capacitors for the compensation of the reactive power and the unbalance power in medium voltage distribution networks with unbalanced loads is proposed. The proposed capacitor allocation reduces power losses in power networks caused by reactive power demand and unbalance. The powers are calculated by the IEEE STD 1459-2010, and presented real values of electrical magnitudes in unbalanced three-phase systems. The results of the capacitor placement obtained from the proposed method are compared with the placement of singlephase capacitors and the placement of balanced three-phase capacitors banks. The results allow to observe the efficient performance of the proposed method for reducing power losses in a 34-bus medium voltage power network with the presence of the neutral conductor. Four cases are simulated with results optimized by the Chu-Beasley genetic algorithm. The purpose of the optimization algorithm is to minimize line loss and capacitor costs.