基于过载特性修正的EV-VSG事件触发控制与最小切负荷优化OA

This paper proposes an event-triggered control and minimum load shedding method based on overload characteristic correction of EV-VSG for village-level DC microgrids under unplanned islanding to address the problems of source-load imbalance,DC bus voltage deviation and the over-shedding problem of traditional fixed-step schemes.First,an event-triggering window is built from the bus voltage deviation and its rate of change.Based on this window,the virtual inertia of EV-VSG is adjusted adaptively,and a limit is imposed on its output.Second,an allowable overload power envelope of the EV is constructed by considering the state of charge(SOC)and efficiency correction,so as to determine the available overload limit.Finally,a load shedding decision mechanism is established according to the power deficit and the available overload capacity of the main energy storage and EVs,and a minimum load shedding model with load priority and granularity constraints is solved.Simulation results show that the proposed method makes voltage recovery smoother and faster.Within the 0～3 s transient period,the cumulative load shedding is about 13.8%of the total load,which is reduced by about 72.3%and 66.0%compared with the two reference strategies.The method makes good use of the EV overload capability and reduces load loss while maintaining system stability.