Online location determination of switched capacitor bank in distribution system

Abstract

This report describes new approaches for the determination of the direction of switched capacitor banks. It is an efficient technique for estimating the distance of switched capacitors from the monitoring location in distribution systems. At first, new indices based on branch voltage and current changes immediately after the capacitor switching instant are proposed for determining the direction of switched capacitor banks. The wavelet transform is used to detect the exact instant of switching. Mathematical analysis of a capacitor bank energizing proves that, the energized capacitor bank affects only the upstream reactive power flow and, the energizing instant, the gradients, time derivatives of voltage and current waveforms measured upstream from the capacitor location will have opposite signs bank by simply evaluating power factor changes and the signs of voltage and current waveform gradients at the switching instant. Simulation results show that the error of the estimated distance is acceptable. Signatures of shunt capacitor bank switching transient phenomena from which one can accurately determine the relative location of an energized capacitor bank whether it is upstream or downstream from the monitoring location.