What does integral windup mean?
When the actuator is saturated and cannot do what the controller asks, the integral term keeps growing, then drives a large overshoot once the actuator can respond again. It is prevented by clamping the integral or pausing it while the output is saturated.
In a lesson
That is integral windup, and it produces the worst overshoot you will ever see from a controller that is otherwise correct.
Learn it
- Taught in U5.4 The integral term Feedback control, University
- Guide with live demos: PID control explained