What is PID control?
PID can be described as a set of rules with which precise regulation of a closed-loop control system is obtained. Closed loop control means a method in which a real-time measurement of the process being controlled is constantly fed back to the controlling device to ensure that the value that is desired is, in fact, being realized. The mission of the controlling device is to make the measured value, usually known as the PROCESS VARIABLE, equal to the desired value, usually known as the SET POINT. The very best way of accomplishing this task is with the use of the control algorithm we know as PID. In its basic form, PID involves three mathematical control functions working together: Proportional-Integral-Derivative. The most important of these, Proportional Control, determines the magnitude of the difference between the SET POINT and the PROCESS VARIABLE (known as ERROR). This then applies appropriate proportional changes to the CONTROL VARIABLE to eliminate ERROR. Many control systems w