Voltage Improvement by a Transformerless Active Voltage Quality Regulator with the Parasitic Boost Circuit

Abstract: Voltage sags have always been a more threat to sensitive industrial and commercial electrical consumers, and deep sags with long duration time are usually more intolerable. In this paper, a new study of series-connected compensator is presented to mitigate long duration deep sags, and the solatium ability is highly improved with an unrivalled shunt converter structure acting as a parasitic boost circuit that has been theoretically analyzed. Additionally, the projected active voltage quality regulator is a cost effective solution for long duration sags that are lower than 50%of the nominal voltage as it is transformerless compared with the traditional dynamic voltage restorer. High operation efficiency is ensured by applying the dc-link voltage adaptive control method. Analysis, along with simulation and experimental results, is presented to verify the feasibility and effectiveness of the projected study.

Keywords: Dynamic Voltage Restorer (DVR), Dynamic Sag Correction, Long Duration Deep Sag, Parasitic Boost Circuit, Series Connect Compensator.