Topic: PID control loop

topics > engineering > Group: process control

digital simulation of analog


The standard control loop for process control is called PID. This consists of a proportional component relating an output signal to an input signal, an integral component for modifying the base line set point, and a derivative component which increases the rate of change according to the error size. The control loop may contain a deadband to prevent hunting when the error is small. (cbb 5/80)
Subtopic: proportional control up

Quote: in proportional control, the change in output is proportional to the error (measurement-setpoint) [»fishJ10_1978]
Quote: a controller may include a deadband which prevents changes for small errors [»fishJ10_1978]
Quote: in most process plants, 80% of loops use simple PI analog controllers; most of these are never adjusted after tuning [»instrumentcontrol]

Subtopic: PID loop up

Quote: in a PID loop, the integral (reset) changes the base level of the output when a setpoint or load changes [»fishJ10_1978]
Quote: in a PID control loop, the derivative (rate/pre-act) is the rate of change of output due to the rate of change of error

Related Topics up

Topic: digital simulation of analog
(8 items)

Updated barberCB 11/04
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