环形直流微电网的二次控制与稳定性分析

Secondary control and stability analysis of ring-bus DC microgrids

本文阐述了一种环形直流微电网系统分布式二次控制的稳定性分析方法,实现了微网系统的电压调控和电流分配.首先,借助多智能体系统的一致性算法,设计了局部观测器来估计所有分布式能源节点的平均电压.然后,基于观测器状态和邻居节点的电流信息设计了融合误差和动态反馈控制器,并通过解耦潮流代数方程得到了关于融合误差的闭环系统.进一步基于图论、线性系统理论和矩阵特征值扰动分析方法,得到了闭环系统的稳定性条件.最后,在环形直流微电网的仿真平台上验证了该方法的有效性.

This paper presents a stability analysis method of distributed secondary control for a ring-bus DC microgrid,where voltage regulation and current sharing of the microgrid are achieved.Firstly,a local observer is designed to estimate the average voltage of distributed energy resource buses based on the consensus algorithms of multi-agent systems.Then,a combined error and its associated dynamic feedback controller are designed using the observer state and current information of neighbors.By decoupling the power flow algebraic equation,the closed-loop system of the combined error is derived.Based on graph theory,linear system theorem,and eigenvalue analysis method on the matrix,stability analysis of the closedloop system is provided.Finally,the proposed method is carried out on a tested ring-bus DC microgrid to demonstrate the effectiveness.