并联DC-DC变换器系统的固定时间分布式协同控制

针对负载为超级电容的并联DC-DC变换器系统,为了在固定时间内实现电流输出均衡目标,提出固定时间分布式协同控制方法.将耦合子系统之间的通信拓扑,利用无向图进行刻画.借助输入输出反馈线性化技术,将并联DC-DC变换器系统的电流均衡控制设计难题转化为固定时间内一阶多智能体系统的一致性跟踪问题.借助符号函数、拉普拉斯矩阵、牵制增益矩阵,基于最近邻原则,设计参数可调的固定时间电流均衡分布式协同控制律.利用李亚谱诺夫函数严格证明整个闭环系统的稳定性,并推导出收敛时间的上界.所提出的固定时间电流均衡分布式协同控制方法,可以克服有限时间协同控制方法对初始状态依赖性强的缺点,同时改善了系统的收敛性.借助仿真,验证了所提出方法的有效性和可行性.

Fixed-time based distributed cooperative control for parallel DC-DC converter systems

In this paper, one class of distributed fixed-time cooperative control scheme is proposed for parallel DC-DC converter systems with super-capacitor loads in order to achieve a current-sharing objective in a fixed time. The communication network between parallel-connected sub-systems is depicted as a undirected graph. With the aid of the input output feedback linearziation technique, the difficult fixed-time current-sharing control design is converted into the consensus tracking problem of first-order multi-agent systems in a fixed horizon. Based on the nearest neighborhood rule, the fixed-time current-sharing cooperative control law with tuneable gains is designed by adopting the sign function, the Lapalican matrix and the pining gain matrix. The closed-loop system stability is rigorously proved using the Lyapunov function and the upper bound of the convergence time is derived accordingly. The proposed fixed-time current-sharing method can overcome the strong dependence on initial system states compared with the finite time control method, which can also improve the system convergence performance. The effectiveness and applicability are verified by simulations.