14.5
PID control
Introduction
PID control (Proportional Integral Derivative control) is a well established and widely used
method for feedback control of processes. This chapter contains a brief discussion about
PID control, and how it is used in ÄKTA ready.
Principles
A PID controller uses the difference (error) between the actual (measured) value and a
desired setpoint to compute the adjustment required in order to keep a process within
defined boundaries.
A typical PID controller is tuned using the following three parameters:
•
P — The weight of the current error. Proportional to the error.
•
I — The weight of the stationary, or long term change in the error. Reduces effects
of error “trends”.
•
D — The weight of the current rate-of-change of the error. Reduces effects of short
term error changes.
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ÄKTA ready Operating Instructions 28960345 AD
14 Reference information
14.5 PID control
