基于解耦方法的TITO分散PID控制器研究

Decentralized PID Controller Design Based on Decoupled System for TITO Processes

介绍一种在工业过程中两输入两输出(TITO)系统控制器的设计及调节方法,提出一种逆向解耦方法,该方法能对具有耦合对象的系统有效的解耦成对角矩阵,以减小各回路之间的耦合影响,解耦矩阵因其结构上较为复杂、物理上不易实现等特点,因此在不加入解耦矩阵的情况下,利用解耦后的对角矩阵对TITO系统进行分散PID控制器的独立设计。首先通过一阶加时滞的模型方法对对角矩阵元素降阶,并对降阶后的模型采用内模控制方法进行控制器各回路PID的参数整定,最后,通过仿真验证了所设计的控制器具有较好的动态性能,并将该方法用于实验室的水箱控制系统中,控制效果良好。

This paper presents a decentralized PID controller design method based on decoupled system for the two-input-two-output （TITO） interactive process. An inverted decoupler is designed, which can decouple the system with coupling objects into a diagonal matrix to minimize the interactive between the loops. Because of the complexity of the decoupling matrix, an independent PID controller is designed for TITO system by using the decoupled diagonal matrix. First, using a model reduction technique, the diagonal matrix is approximated to the first order plus dead time （FOPDT） form. Then, the individual controller of each single loop is then independently designed by applying the internal model control （IMC）-based PID tuning approach for single-input/single-output （SISO） systems. Finally, simulation examples and comparison with other works demonstrate the effectiveness of this methodology, and the methods are combined and tested in an experimentation of the water tank.