废水中和处理pH值控制的研究与实践

根据pH对象的特性曲线，设计了一种利用非线性增益补偿pH静态增益的变化，同时运用模糊前馈系统抑制pH超调的前馈 反馈非线性控制模型，实现了pH值的闭环控制，并且在实际运用中取得了较好的效果．

A new class of nonlinear controllers with pH control

The acid/base neutralisation in plants is a very highly non|linear process as shown by the shape of the neutralisation curve. pH cantral is important for many processes such as boiler water treatment, biochemical reaction. Because of the high non|linearity, a linear controller can only perform well with in a small pH range. This paper presents an innovative approach to controller design, and applies it to the pH|control problem. The proposed approach uses a new non|linear controller. comprised of a non|linear cascade gain and a linear fixed|gain PID controller, and two fuzzy logical controllers in order to retrain the over|shoret of pH and flow respectively. This approach applied to the design and evaluation of a control system for a electrical chemical plant yielded good performance over widely varying conditions. These results showed the superior performance of the non|linear controller ouer that of a fixed|gain PID controller.