DSTATCOM integrated with Y-y connection transformer for reactive power compensation

Abstract

This paper proposes a distribution static synchronous compensator (DSTATCOM) integrated with a Y-y connection transformer for reactive power compensation. A cascaded DSTATCOM is connected to a group of taps on the primary windings of the transformer to form an integrated structure. The proposed structure can achieve a flexible connection point voltage selection to achieve a compromise between the voltage rating and current rating. Therefore, the initial investment, voltage stress and size of the compensation system can be reduced. The winding currents distribution and compensation capacity constraint are analyzed in detail to determine the attainable compensation range. To improve the dynamic response performance of the system, a feedforward compensation control strategy is introduced in this paper. To prevent the transformer windings from overcurrent, a reactive reference current calculation method is also presented. Finally, both simulation and experimental results are provided to verify the effectiveness of the proposed system.