The transfer function model for level control of a water
tank system is described by a first order transfer function:
G(s) = 2
30s + 1
where the input is the flow rate and the output is the fluid level in the
tank. Design a PI controller to regulate the fluid level, where the desired
closed-loop performance is specified by the closed-loop polynomial s
2 +
2ξwns + w
2
n
, ξ = 0.707 and wn = 1. Simulate the closed-loop output
response to a unit step set-point signal.
