兼顾SOC均衡与电压偏差的自适应下垂控制策略OA

In islanded DC microgrids,line impedance and load fluctuations lead to uneven power distribution and voltage deviation,threatening system stability and affecting energy storage lifetime.Existing droop control strategies need to preset a fixed initial droop coefficient,which makes it difficult to balance the storage state of charge(SOC)equalization accuracy and voltage deviation suppression.To address this problem,an adaptive control strategy based on the LSHADE algorithm to optimize the droop parameters was proposed.The strategy adopted a layered structure:the communication layer utilized the consistency algorithm to obtain the average value of the system through low-bandwidth communication;the droop control layer designed a new type of allocation factor based on the inverse tangent function,and constructed a weighted objective function of the droop coefficient and the voltage reference,and then solved the optimal parameter by applying the LSHADE algorithm in real time;the direct control layer drived the DC/DC converter.Simulation results show that the proposed strategy has two core advantages:firstly,there is no need to preset the initial droop factor,eliminating the limitations of the traditional methods;secondly,there is no need to add a new control link in power-constrained scenarios,and the output power can be tightly limited,while the existing schemes require complex additional control.In the case of initial difference in storage SOC(75%/73%/70%)and capacity(5∶5∶3),the deviation of SOC equalization is less than 0.004%,and the deviation of bus voltage is less than 1%;the voltage fluctuation under load fluctuation is only 0.9 V;in the case of power constraints of the converter(1 900 W),SOC equalization is achieved within 40 s and the power does not strictly go beyond the limit,which is significantly superior to the traditional strategy of switching control modes.