4. (a) How to determine when a controller is at its best performance? Justify your
answers.
(10 marks)
(b) In your opinion, why it is important to tune a PID controller?
(5 marks)
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KKKR3713
(c) As a control engineer, you are required to monitor the bottom product composition
of a distillation column to separate alcohol and water. The bottom composition
shows offset, oscillation, and high overshoot from its response curve.
(i) What type of controller used for this distillation column? Justify.
(5 marks)
(ii) Tune the controller in 4(c)(ii) with ONE (1) tuning method of your choice.
Provide the steps to perform the tuning in a flowchart.
(10 marks)