基于动态扩散算法的直流微电网简化分布式二层控制  

Simplified distributed secondary control based on dynamic diffusion algorithm in DC microgrid

作　　者：廖达威 高飞[1,2] LIAO Dawei;GAO Fei(Key Laboratory of Control of Power Transmission and Conversion,Ministry of Education,Shanghai Jiao Tong University,Shanghai 200240,China;Department of Electrical Engineering,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]上海交通大学电力传输与功率变换控制教育部重点实验室,上海200240 [2]上海交通大学电气工程系,上海200240

出　　处：《电力自动化设备》2024年第1期119-125,共7页Electric Power Automation Equipment

基　　金：上海市自然科学基金资助项目(22ZR1429800)。

摘　　要：孤岛直流微电网采用下垂控制实现电流均分时,均流效果受馈线阻抗影响且带来电压跌落。为实现电压恢复和电流精确均分,提出了一种采用动态扩散算法的简化分布式二层控制策略。相比于传统二层控制,该简化二层控制策略仅包含1台积分控制器和1个通信变量,简化了控制结构,减轻了通信链路负担。策略采用动态扩散算法进行分布式通信,改善了系统的收敛速度以及稳定性。考虑到不可忽略通信采样时间对系统稳定性的影响,建立了系统的离散时间小信号模型,绘制根轨迹图分析了二层控制增益和通信采样周期等关键参数对系统稳定性的影响。最后,基于MATLAB/Simulink的仿真结果验证了所提策略在动态性能和稳定性上的优越性。When droop control is used to achieve current sharing in islanded DC microgrid,the current sharing performance is affected by feeder impedance and the voltage drop is caused.In order to achieve both voltage restoration and accurate current sharing,a simplified distributed secondary control strategy based on dynamic diffusion algorithm is proposed.Compared with the traditional secondary control,the proposed strategy only includes one integral controller and one communication variable,which simplifies the control structure and reduce the burden of communication links.The strategy adopts a dynamic diffusion algorithm for distributed communication to improve the convergence speed and stability of the system.Considering the impact of communication rates on the system stability,a discrete-time small-signal model of the system is established,based on which the influence of key parameters on the system stability,such as secondary control gains and communication rates,is analyzed through plotting the eigenvalue diagrams.Finally,the simulative results based on MATLAB/Simulink verify the superiority of the proposed strategy in dynamic performance and stability.

关 键 词：直流微电网 分布式控制 扩散算法 离散时间模型 二层控制 

分 类 号：TM761[电气工程—电力系统及自动化]