An Arcless Step Voltage Regulator based on Paralleled Power Electronics Converter Configuration

Abstract

Step Voltage Regulators (SVR) have been widely used in power distribution systems for decades. However, the tap changing mechanism of the conventional SVR always generates electric arc under oil when tap changes, which imposes constraints on the conventional step voltage regulators, such as lifetime and maintenance period. This paper proposed a new scheme of arcless voltage regulator featured with power-electronics-assisted tap changing topology. A power converter is introduced to eliminate arc for the tap changing operation and is only rated 0.3% of the system’s full power rating. A scaled-down prototype of the arcless SVR is developed to verify the proposed arcless tap changing method. Hardware test results are presented in the paper. The proposed method can eliminate electric arc during the tap changing and significantly reduce the contact electrical erosion rate by over 11000 times when compared with the conventional SVR, hence to extend the lifetime of the SVR, save maintenance labor hours and operation cost.