| 摘要 |
<p>PROCESS CONTROL A process control system is provided in which a process variable is compared to a set point for the process variable by a process controller with the results of the comparison being utilized to control the process in such a manner that the process variable will be substantially equal to the set point for the process variable. A critically damped response of the process variable to a change in the set point is achieved by utilizing a process controller which has the characteristics of a proportional-integral-derivative controller followed by a first order lag. Tuning of the process controller is accomplished by changing a time constant which is common to the proportional, integral and derivative terms of the proportional-integral-derivative controller and also common to the first order lag.</p> |
