In a closed-loop process control system with a PID controller, __
A. proportional
B. integral
C. differential
D. All of these
Please scroll down to see the correct answer and solution guide.
Right Answer is: D
SOLUTION
Explanation:
\(\frac{{C\left( s \right)}}{{R\left( s \right)}} = \frac{{\left( {s{T_d} + K + \frac{{{K_I}}}{s}} \right)G\left( s \right)}}{{1 + \left( {s{T_d} + K + \frac{{{K_I}}}{s}} \right)G\left( s \right)}}\)
It represents the PID controller.
Close loop transfer function depends on all type of controller.
e(s) ∝ sTd (Derivative controller)
e(s) ∝ K (Proportional controller)
e(s) ∝ KI/s (Integral controller)
Condition for PID controller:
|K(s) × G(s)| = 1 and
∠K(s) × G(s) = 180°
where K(s) = sTd + K + KI/s
PID controller is an instrument used in control applications to regulate flow, speed, pressure, temperature and other variable process.
