Research on Control Strategy of Distributed Generation Grid-connected Inverter

Abstract

Under the carbon peak and carbon neutrality goals, it is inevitable to build a new power system with new energy as the main body. The grid-connected operation of distributed power must be able to meet the requirements of voltage and frequency support of the grid. This paper presents multiple control modes of grid-connected inverter, including dispatching mode and no dispatching mode. Then, droop control strategy based on multi-mode switching and zone control strategy based on offset are proposed. The droop control strategy of multi-mode switching is to make the inverter run in different modes such as f-P, V-Q and P-Q according to information for power system dispatching. The zone control strategy based on the offset is the inverter adopts different control methods when power system run in different regions that was divided according to the offset, and enables the distributed power to participate in the power grid voltage and frequency adjustment independently. MATLAB simulation result shows the correctness and effectiveness of the control strategy adopted in this paper.