基于无线传感器网络的控制系统采样频率优化算法

Optimization algorithm for sampling frequency assignment in wireless sensor network-based control system

针对基于无线传感网的网络化控制系统,讨论了采样频率的优化问题.建立了以数字和模拟控制系统性能差距指数最低为目标,以无线节点的通信容量为约束条件的非线性优化模型,并以障碍函数法进行求解,提出了基于节点缓冲区信息的分布式迭代算法.该算法在传感节点的计算量小,易于实现.仿真表明该算法能有效收敛到系统的最优目标点,并能适应于系统的负载变化.

A sampling frequency assignment problem is discussed in networked control systems which are based on wireless sensor network. The problem is formulated as a nonlinear optimization problem, whose objective function is to minimize the difference indexes between the digital and the anolog control systems, subject to node communication capacity constraints. With a barrier function method, an iterative distributed algorithm based on local buffer information is then proposed. This algorithm has features of low computational complexity and good feasibility. Simulation results show that the frequency sequence generated by the iterative distributed algorithm can effectively converge to an optimal solution, and can adapt to the changes of system load.