基于多组储能动态调节的独立直流微电网协调控制

Coordinative control based on dynamic load allocation among multiple energy storages for islanded DC microgrid

针对独立运行的直流微电网,提出基于多组储能系统动态调节的协调控制策略。孤岛运行模式下,分布式电源采用最大功率点跟踪(MPPT)控制,并选择配置多组储能来维持母线电压稳定。通过设计带有电压前馈补偿的模糊下垂控制动态调整负荷功率分配,实现不同储能单元荷电状态(SOC)的快速均衡,保证多组储能单元之间的协调运行,并可减小母线电压波动。当储能系统因满充等原因退出运行后,分布式电源由MPPT控制切换为下垂控制,并根据自身的最大功率自动调整负荷功率分配,确保重要负荷正常供电和微电网的安全运行。同时,在分布式电源下垂控制器的功率环节增加前馈补偿控制,减小该模式下母线电压波动。利用MATLAB/Simulink搭建仿真模型,仿真结果表明所提的控制策略可有效减小电压波动并能实现独立直流微电网稳定运行。

A strategy of coordinative control based on （Energy Storages） is proposed for islanded DC microgrid. the dynamic load allocation among multiple ESs In the islanding mode,DGs（Distributed Generations） are under the MPFF（Maximum Power Point Tracking） control and multiple ESs are applied to stabilize the bus voltage. Fuzzy droop control with voltage feed-forward compensation is designed to dynamically allocate the load power among muhiple ESs for balancing their states of charge,which ensures their coordinative operation and reduces the bus voltage fluctuation. When ESs are fully charged,the ES system will be out of service,the control mode of DGs will change over from MPPT to droop control,which automatically allocate the load power according to their maximum powers to ensure the power-supply for important users and the safe operation of microgrid. The voltage feed-forward compensation is added to the power loop of droop control to reduce the bus voltage fluctuation. Results of MATLAB/Simulink simulation indicate that,the proposed control strategy reduces the voltage fluctuation effectively and realizes the stable operation of islanded DC microgid.