How do I get the closed-loop transfer function of the system, fitted with a PID controller, if the input valve has a transfer function given by:
$ \frac{Q(s)}{P(s)} = \frac{Kv}{(Tv*S+I)} $
Where Kv is a constant of proportionality between the steady-state discharge and the pressure on the input valve. Tv is the time constant of the input valve.
I'm not sure how I'm meant to use the input valve transfer function to work out the closed-loop system transfer function.
Could anyone help explain the steps?