A system with a controller is shown in Figure AP5.5. The zero of the controller may be varied. Let α = 0, 10, 100.
(a) Determine the steady-state error for a step input r(t) for α = 0 and α ‰  0.
(b) Plot the response of the system to a step input disturbance for the three values of α. Compare the results and select the best value of the three values of α.
Figure AP5.5
System with control parameter α.

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