Consider the negative unity feedback configuration with gain k in the feedforward path.
The closed loop is stable for k < k0. The maximum value of k0 is ______.
Your input ____
2
GATE ECE 2018
Numerical
+2
-0
For a unity feedback control system with the forward path transfer function
$$G(s) = {K \over {s\left( {s + 2} \right)}}$$
The peak resonant magnitude Mr
of the closed-loop frequency response is 2. The
corresponding value of the gain
K
(correct to two decimal places) is _________.
Your input ____
3
GATE ECE 2017 Set 1
MCQ (Single Correct Answer)
+2
-0.6
The Nyquist plot of the transfer function
$$G(s) = {k \over {\left( {{s^2} + 2s + 2} \right)\left( {s + 2} \right)}}$$
does not encircle the point (-1+j0) for K = 10 but does encircle the point (-1+j0) for K = 100. Then the closed loop system (having unity gain feedback) is
A
stable for K = 10 and stable for K = 100
B
stable for K = 10 and unstable for K = 100
C
unstable for K = 10 and stable for K =100
D
unstable for K = 10 and unstable for K = 100
4
GATE ECE 2017 Set 2
MCQ (Single Correct Answer)
+2
-0.6
A unity feedback control system is characterized by the open loop transfer function
$$G(s) = {{10k\left( {s + 2} \right)} \over {\left( {{s^3} + 3{s^2} + 10} \right)}}$$
The Nyquist path and the corresponding Nyquist plot of g(s) are shown in the figures below.
If 0 < K < 1, then number of poles of the closed loop transfer function that lie in the right half of the s-plane is
If 0 < K < 1, then number of poles of the closed loop transfer function that lie in the right half of the s-plane is