具有容性负载的直流微电网系统分布式协同控制

Distributed Cooperative Control of DC Micro-Grid Systems With Capacitive Loads

针对一类具有容性负载的直流微电网系统,提出了分布式协同控制方法.具有容性负载的直流微电网是一类耦合动态互联非线性网络化系统,可将DC-DC变换器在信息层视为智能体,在每个子系统模块中,引入容性负载电压观测器,耦合并联非线性系统负载均衡控制设计问题可解耦成一阶积分器多智能体系统的输出一致性跟踪问题.基于最近邻原则,通过在控制器中引入比例、积分环节,设计了增益可调的分布式协同PI控制律,当有向图满足至少含有一棵生成树的条件下,通过子系统间的局部交互,可以实现负载均衡的目标.通过分析增广系统矩阵的特征值证明了整个闭环系统的稳定性.仿真和实验说明了所提出的控制方法的有效性及可行性.

In this paper,a distributed cooperative control is proposed for DC micro-grid systems with capacitive loads that is the coupled dynamical interconnected nonlinear networked systems.By considering each DC-DC converter as an agent in the cyber layer and introducing voltage observers for capacitive loads in each sub-system,the coupled nonlinear dynamics is decoupled into a first-order integrator and the load-sharing control design is converted into an output consensus tracking problem of such linear multi-agent system.Based on the nearest neighborhood rule,a distributed cooperative PI control law with tunable gains is designed accordingly by adopting proportional and integral control loop.The load-sharing objective is achieved through local interaction in a cooperative way provided that the directed graph at least has a spanning tree.The overall closed-loop system stability is rigorously proved by analyzing the eigenvalues of the augmented system's matrix.Simulations and experimental results verify that the proposed approach is effective and feasible.