Improved Droop Voltage Control Strategy Considering the Access of Energy Storage and Distributed Generation

Owing to the difference of capacity and initial state of charge (SOC) for the multi-group energy storage units, as well as the different line resistance, the SOC of the energy storage unit cannot be equalized under the traditional droop control, which may cause the energy storage unit overcharged or overdischarged, and shorten its lifespan. Therefore, the improved droop control is designed based on the operation current and SOC, which can be obtained by taking advantage of the sample keeper and deduced by the consistency algorithm through the information interaction between neighboring agents. So the improved droop control can adjust the droop factor and voltage compensation by period, thus eliminating the influence of the above factors on the current load distribution and reduce the dependence on communication. Therefore, the current and SOC of the energy storage units may be balanced to avoid overcharged and overdischarged. Finally, the effectiveness and correctness of the proposed strategy is verified by RTLAB real-time simulation experiments.