Three-phase Voltage Control Method by Single-phase Distributed Generators Connected to Islanded Distribution Network

Abstract

We have proposed a concept model of emergency islanded operation by using distributed generators (DGs) such as PVs, EVs or batteries which can provide power to customers via undamaged distribution network in order to develop the resilient power system against large disasters, and it is named Islanded Distribution Network (IDN). Since there is no guarantee that the three-phase generation system is interconnected to the IDN, the single-phase DGs which are installed in the distribution network may be treated as main generators in the IDN operation. If the IDN has only single-phase DGs, it is difficult to regulate the three-phase voltage within the allowable range and to compensate the unbalance voltage. The aim of this study is to develop the method to supply three-phase balanced voltage by single-phase generators in the IDN. First, the operating condition of the generators is proposed for the supply of three-phase balanced voltage in the IDN model by algebra calculation. The control method for three single-phase generators has been developed by using the conditions obtained from the derivation of the generators conditions.