Improvement of droop control strategy for grid-connected inverters in microgrids

The traditional droop characteristic microgrids may result in control errors because of the output impedance and line impedance. In this paper, the active and reactive circulating current of the parallel system model and the traditional droop characteristic were analyzed. Considering the output impedance and line impedance, the reactive power sharing improperly was analyzed. Because of the improper power sharing problem can not be improved by the control scheme, the improved power decouple control scheme was proposed. The improved droop algorithm can improve the condition of the power sharing. And then the proposed control scheme was verified by the MATLAB/Simulink simulation. The improved algorithm reduced the inverters control error, and got a better dynamic response. The study improves the control accuracy of the microgrids.