纯滞后或大滞后对象在工业过程控制中是很普遍的。这类对象很难控制,用常规的 PID 方法不容易得到好的控制品质。较先进的控制方法是采用 Smith预估补偿控制。而采用这一方法必须要有一台纯滞后预估补偿器。为此本文提出用采样保持的方法,曾成功地研制出一台纯滞后时间可长达4000秒的预估补偿器,经长期实际运行,得到了满意的结果。文中介绍了这种补偿器的构成原理、线路设计方法及参数选择,并给出了原理线路。最后对用这种补偿器组成Smith 控制系统及系统整定等问题进行了讨论 Purely lagged or large-hysteresis objects are common in industrial process control. Such objects are difficult to control and not easy to get good control quality with conventional PID methods. The more advanced control method is to use Smith’s predictive compensation control. The use of this method must have a purely lag prediction compensator. For this reason, this paper presents a sample-and-hold method and has successfully developed an estimated compensator with a pure delay time of 4000 seconds. After long-term actual operation, satisfactory results have been obtained. This paper introduces the composition of this compensator principle, circuit design method and parameter selection, and gives the principle of line. At last, the problems of Smith control system and system tuning using this compensator are discussed