I was reading about on/off, P,I,D and lead,lag compensators, questions are
1)Are there any example of a system which can work appreciably well without controllers.
2) How do I decide that I need a particular type of controller as listed above
You figure out how it works without the controller and figure out what the system is missing (or has very little).
Based on that, you choose the controller that helps you improve the thing that is missing or has very little of it.
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1)Are there any example of a system which can work appreciably well without controllers.
By adding a P to say a second order system , I find change in the transient response. But my question is what takes you from no controller to choosing a P controller, if quicker transient response is not the goal.
Hi CataM,
By adding a P to say a second order system , I find change in the transient response. But my question is what takes you from no controller to choosing a P controller, if quicker transient response is not the goal.
Yeh, I got the point. Control system's goal are three fold, Viz. Transient, steady state and stability. So With the feedback (with no controllers) if the goals are not satisfactory, then we go about different combinations to achieve the target. So this is clear.
This brings me to next level of clarification about the proof for PID controller math(particularly why P+I+D and why not P*I*D or any other combo)