针对一类工业过程运行控制中采用无线网络传输运行指标反馈值时存在的噪声和丢包问题,建立了输入为过程控制的输入输出、输出为运行指标的随机过程模型;提出了由不同采样速率的过程控制与过程控制设定值反馈控制组成的运行反馈控制方法;采用Lyapunov函数和不同采样频率的提升技术设计了过程PI控制器参数和过程控制设定值反馈控制器参数,保证了双闭环控制系统的随机稳定性;同时实现了运行指标实际值与目标值稳态误差的均值为零;通过浮选过程运行反馈控制仿真实验验证了本文所提方法的有效性.
This paper studies operational control design for a class of industrial processes in which the operational index is transmitted back via wireless networks, whose noise and packet dropout may negatively affect the operational control performance. Firstly, a stochastic process model of operational index is established with the input and output of process control as its input and the operational index as its output. Secondly, a dual-layer model combining process control and set-point feedback control is presented with different sampling rates. Thirdly, a Lyapunov function and a lifting method between multirate systems are adopted to design a process PI controller and a set-point feedback controller to guarantee the stochastic stability of the dual closed-loop control system and that the mean value of steady-state error between the realistic and target operational index is zero. Finally, a simulation experiment on the operational feedback control in an industrial flotation process is conducted to demonstrate the effectiveness of the proposed method.