Optimal capacitor placement for improving power quality

In this paper, the optimal capacitor placement problem is studied. Traditionally, the solution to this problem aimed to minimize the system losses and capacitor costs. This study also accounts for the voltage harmonic distortion brought about by the placement of capacitors. A current injection based model is used for representing the network, operating at various harmonic frequencies. Thus, all nonlinear loads are assumed to be representable by their harmonic current injections. The optimal capacitor placement problem is formulated as a mixed integer nonlinear programming problem which determines the location, type and size of the shunt capacitors to minimize the harmonic levels, losses and the capacitance costs. A heuristic method is used to obtain a near optimal solution for realistic size systems