By Bob Rice1 and Doug Cooper The control objective for the pumped tank process is to maintain liquid level at set point by adjusting the discharge flow rate out of the bottom of the tank. This process displays the distinctive integrating (or non-self regulating) behavior, and as such, presents an interesting control challenge. The process […]
By Bob Rice1 and Doug Cooper Integrating (or non-self regulating) processes display counter-intuitive behaviors that make them surprisingly challenging to control. In particular, they do not naturally settle out to a steady operating level if left uncontrolled. To address this distinctive dynamic character, we modify the controller design and tuning recipe to include a FOPDT […]
By Bob Rice1 and Doug Cooper As has been discussed elsewhere in this e-book, it is best practice to follow a formal recipe when designing and tuning a PID controller. A recipe lets us move a controller into operation quickly. And perhaps most important, the performance of the controller will be superior to one tuned […]
By Bob Rice1 and Doug Cooper The case studies on this site largely focus on the control of self regulating processes. The principal characteristic that makes a process self regulating is that it naturally seeks a steady state operating level if the controller output and disturbance variables are held constant for a sufficient period of […]