Parker Aries AR-04CE - Controlling Integral Windup; Figure 34 Integrator Windup (Without Using ILIMIT)

Parker Hannifin
- 56 - Aries Controller Hardware Installation Guide
Controlling Integral Windup
If you are using integral control (IGAIN) and there is an appreciable position
error that persists long enough during the transient period (time taken to
reach the setpoint), the control signal generated by the integral action can
end up too high; this saturates to the maximum level of the controller's
analog control signal output. This phenomenon is called integrator windup
(see Figure 34.)
Figure 34 Integrator Windup (Without Using ILIMIT)
After windup occurs, it takes time before the integrator output returns to a
level within the limit of the controller's output. Such a delay causes excessive
position overshoot and oscillation.