Patent ID: 7183751
Filing Date: 2007-02-27
Classification: H02J,Y02E

Abstract:
1. A reactive power compensator device comprising: an AC capacitor set providing a fundamental reactive power; a power converter serially connected with the AC capacitor set, said power converter comprising: a power electronic switch set having a bridge configuration providing one or more arms according to a phase number of power systems, and containing two DC terminals and one or more AC terminals depending on the number of arms; a DC capacitor acting as an energy buffer to supply the power electronic switch set with a dc vo a high-frequency ripple filter adapted to filter a high-frequency ripple current generated by a switching operation of the power electronic switch set; and a controller arranged to generate drive signals and sent them to the power electronic switch set such that the power converter controls reactive power compensation to provide a fundamental reactive power current. wherein one power line of the power system connects to one of the two DC terminals of the power electronic switch set without passing through any power electronic switch to permit omission of one arm of the power electronic switch set; and wherein switching the power electronic switch set controls said reactive power compensator device to supply a nearly sinusoidal compensation current; whereby the serial connection of the AC capacitor with the power converter avoids problems of power resonance and harmonic current injection and reduce the capacity of the power converter.