Optimal Placement and Sizing of Capacitor Banks in Harmonic Polluted Distribution Network

In this paper, the optimal sizing and locating of capacitor banks in a 15-bus standard distribution network with harmonic effects consideration has been studied. The goal was finding the size and location of capacitor banks with power loss reduction approach and voltage stability improvement in the network. Considered constraints in optimization are capacity of capacitor banks, voltage limitation, and total harmonic distortion (THD) limit. Due to the nonlinear nature of the capacitor placement problems in the distribution network, non-linear methods should be used. Thus, the Harmony Search Algorithm (HS) has been used to achieve this goal. In simulations, first, by using the Power Loss Index (PLI) on the buses, locations of the banks were determined and then, using the HS algorithm, the appropriate capacities of the banks are calculated. Two scenarios are studied in this paper. In first scenario, it is assumed that there is no harmonic in the network, and in the second scenario, studies are conducted in the presence of harmonic loads. The results indicate that considering harmonics in the capacitor placement problem will have a noticeable influence on the network characteristics, hence it must be considered in studies.