1
GATE ECE 1998
Subjective
+5
-0
The characteristic equation of a feedback control system is $$$s^4+20s^3+15s^2+2s+K\;=\;0$$$
(i) Determine the range of K for the system to be stable.
(ii) Can the system be marginally stable? If so, find the required value of K and the frequency of sustained oscillation.
2
GATE ECE 1998
MCQ (Single Correct Answer)
+1
-0.3
In the Bode-plot of a unity feedback control system, the value of phase of G($$j\omega $$) at the gain cross over frequency is $$ - 125^\circ $$. The phase margin of the system is
A
$$ - 125^\circ $$
B
$$ - 55^\circ $$
C
$$ 55^\circ $$
D
$$ 125^\circ $$
3
GATE ECE 1998
MCQ (Single Correct Answer)
+1
-0.3
The Nyquist plot of a loop transfer function G$$(j\omega )$$ H$$(j\omega )$$, of a system encloses the (-1, j0) point. The gain margin of the system is
A
less than zero
B
zero
C
greater than zero
D
infinity
4
GATE ECE 1998
Subjective
+5
-0
The loop transfer function of a single loop control system is given by $$G(s)H(s) = {{100} \over {s\left( {1 + 0.01s} \right)}}{e^{ - ST}}$$ Using Nyquist criterion, find the condition for the closed loop system to be stable.
EXAM MAP
Medical
NEET
Graduate Aptitude Test in Engineering
GATE CSEGATE ECEGATE EEGATE MEGATE CEGATE PIGATE IN
CBSE
Class 12