Reachability Analysis of Droop-controlled Microgrids Considering Uncertainty

Considering the uncertain factors in droop- controlled microgrids, a reachability analysis method based on zonotopes was proposed to study the dynamic performance of the system under uncertainties. Firstly, zonotopes were used as set representation to describe the uncertain variables of the system, and the calculation method for reachable set of linear dynamic system was presented. Then, based on the dynamic model of the droop-controlled microgrid, simulation analysis was performed on a microgrid test system, and the effectiveness of the proposed method was verified by time domain sampling simulation. The results show that reachability analysis method can consider the continuous impact of various uncertain factors, compute the bounds of all possible dynamic trajectories and determine the maximum fluctuation range of state variables such as frequency and voltage by one single simulation, so as to analyze the system dynamic security and stability under uncertain conditions. © 2019 Chin. Soc. for Elec. Eng.