自治直流微电网分布式经济下垂控制策略

A Distributed Droop Control Scheme for Islanded DC Microgrid Considering Operation Costs

经济下垂控制策略由于考虑了并联机组发电成本、运行效率、治污成本等因素,有效地解决了传统下垂控制策略运行成本高、效率低的问题。该文鉴于已有经济下垂控制策略的不足,提出了一种分布式经济下垂控制策略。该策略利用分布式一致性算法迭代寻找发电单元的最优经济运行点,并同时改变下垂控制的系数,使得收敛后微电网总的运行成本最低。文中所提的分布式策略兼具集中控制及自治控制的优点,由于没有中心控制器,增加了控制的鲁棒性及灵活性。利用Matlab/Simulink搭建具有不同运行成本单元的直流微电网模型,在JADE平台上开发所提策略,通过联合仿真验证了控制策略的有效性。对延时的影响进行了详细分析,并提出了相应的解决措施;设计了节点的投退协议,仿真验证了所提策略的即插即用特性。

The novel economic clroop control strategy with considering of factors like generation cost, efficiency, and emission penalty has effectively solved the problems brought by conventional droop controls, which mainly focuses on achieving proportional power sharing but not others. A distributed cost-based droop control strategy was proposed, and the optimal operation was achieved based on distributed consensus algorithm which would update the droop coefficient synchronously. The proposed distributed strategy has advantages of centralized control and autonomous control. Due to having no central controller, the robustness and flexibility of the control are increased significantly. A DC microgrid model including DGs with different operation costs was built based on Matlab/Simulink, and JADE （Java agent development framework） was used to develop distributed strategy. Then, the effectiveness of the control strategy was verified based on simulation. The influence of communication delay was analyzed at length, and the improved methods were proposed. In order to verify the ＂plug and play＂ capability, the scheme of adding nodes was designed and simulated.