An improved power sharing control scheme of distributed generation converters in microgrid

Abstract

This paper proposes an improved power sharing control scheme to achieve the accurate power sharing control and offer an improved PCC voltage regulation capability in islanding microgrid. An enhanced virtual impedance design is assumed in the conventional droop control scheme to manage distributed generation (DG) units to export the accurate reactive power in proportion to their rating. A point of common coupling (PCC) voltage restoration control is implemented to eliminate the PCC voltage deviation produced by the droop control effect and voltage drop effect on the impedance. This control scheme of each individual DG unit was designed to only use the locally measured feedback variables of inverter. It can realize accurate reactive power sharing and guarantee the PCC voltage quality. Matlab simulations are presented to show the effectiveness of proposed control performance in islanding microgrid.