Control strategy for parallel-operated virtual synchronous generators

Abstract

In order to improve the frequency stability of the micro-grid, virtual synchronous generators are applied to the micro-grid. However, larger virtual inertia cause power oscillation when VSG connected into micro-grid, so a restraint method by adjusting virtual synchronous reactance, damping coefficient and difference coefficient is suggested under inertia time is constant. In addition, a method is proposed for connecting grid of parallel system. Simulation and experimental results verify the effectiveness of the proposed control strategy in this paper.