A single-phase to three-phase UPQC topology with universal filtering capabilities

This paper presents a single-phase to three-phase unified power quality conditioner (UPQC) system, which uses dual control strategy to perform series-parallel active power line compensation. The proposed system is indicated to be applied in remote rural areas, which usually are supplied by only single-phase systems, and, hence, three-phase four-wire or three-phase four-wire systems are not available to provide power for three-phase loads. The UPQC system is able to drain sinusoidal current from the single-phase utility grid, such that high power factor is carried out. In addition, voltage harmonic suppression and voltage sag/swell compensation are achieved, such that the three-phase output voltages are balanced, regulated and sinusoidal with low harmonic contents. Simulation results are presented to evaluate the performance of the UPQC system, taking into account the power flow through the series and parallel converters.