【摘要】 以一实测中和滴定曲线为例，引出缓冲指数及平衡迟缓的概念。从而说明酸碱中和（ｐＨ）控制的困难性。然后文章指出一般的位式控制和常规的反馈控制难以克服ｐＨ控制对象的强非线性和大滞后特性。因此研制一种既可用于一般工业过程又经济的ｐＨ控制系统十分必要。最后文章简要地介绍了作者研制Ｓ７２００ｐＨ控制系统，在间歇流程及连续过程中使用的控制系统方案、软件程序框图及使用情况。同时指出Ｓ７２００ｐＨ系统的优异特性及尚待研究的有关问题。更多还原

【Abstract】 This paper obtains the concepts of buffer exponent and equilibrium lag from a practical neutralization titration curve and shows the difficulties of controlling the pH neutralization process Then it points out that the normal position control strategies and the conventional feed-back control strategies can not deal with the heavy nonlinear behavior and the great time lag of the pH control process So it is necessary to develop a control system for pH process which is financially practical and can be used in the industrial process of pH control This paper also describes the control strategies, software and program framework of the S7-200 pH control system which is used in the continuous system and intermittent system Finally, the author points out the excellent performance of the S7-200 pH control system and the problems to be solved更多还原