Operation of the unified power controller as harmonic isolator

Abstract

The Unified Power Controller (UPC) is a tool in the implementation of Flexible AC Transmission Systems (FACTS). It provides for the equivalent of static VAr compensation and series injection using back-to-back force commutated converters. This paper proposes a control strategy to extend UPC operation to allow for the isolation of harmonics due to non-linear loads. Simulation results based on the Electromagnetic Transients Program (EMTP) are used to illustrate device performance in a power system environment. Experimental results based on a single phase laboratory implementation verify the proposed control algorithm.