1
GATE ECE 2000
MCQ (Single Correct Answer)
+1
-0.3
An amplifier with resistive negative feedback has two left half-plane poles in its open-loop transfer function. The amplifier
A
will always be unstable at high frequencies
B
will be stable for all frequencies
C
may be unstable, depending on the feedback factor
D
will oscillate at low frequencies
2
GATE ECE 2000
Subjective
+8
-0
For the linear, time-invariant system whose block diagram is shown in Fig. with input x(t) and output y(t), GATE ECE 2000 Control Systems - Time Response Analysis Question 7 English 1 GATE ECE 2000 Control Systems - Time Response Analysis Question 7 English 2
(a) Find the transfer function.
(b) For the step response of the system [i.e. find y(t) when x(t) is a unit step function and the initial conditions are zero]
(c) Find y(t), if x(t) is as shown in Fig. and the initial conditions are zero.
3
GATE ECE 2000
Subjective
+5
-0
The block diagram of a feedback system is shown in Figure. GATE ECE 2000 Control Systems - Time Response Analysis Question 9 English 1 GATE ECE 2000 Control Systems - Time Response Analysis Question 9 English 2
(a) Find the closed loop transfer function.
(b) Find the minimum value of G for which the step response of the system would exhibit an overshoot, as shown in Figure.
(c) For G equal to twice this minimum value, find the time period T indicated in Figure.
4
GATE ECE 2000
Subjective
+5
-0
A certain linear, time-invariant system has the state and output representation shown below: $$$\eqalign{ & \left[ {\matrix{ {\mathop {{x_1}}\limits^ \bullet } \cr {\mathop {{x_2}}\limits^ \bullet } \cr } } \right] = \left[ {\matrix{ { - 2} & 1 \cr 0 & { - 3} \cr } } \right]\left[ {\matrix{ {{x_1}} \cr {{x_2}} \cr } } \right] + \left[ {\matrix{ 1 \cr 0 \cr } } \right]u \cr & y = \left( {\matrix{ 1 & 1 \cr } } \right)\left[ {\matrix{ {{x_1}} \cr {{x_2}} \cr } } \right] \cr} $$$
(a) Find the eigen values (natural frequencies) of the system.
(b)If u(t)=$$\delta \left( t \right)$$ and x1(0+)=x2(0+)=0, find x1(t),x2(t) and y(t), for t>0.
(c)When the input is zero, choose initial conditions $${x_1}\left( {{0^ + }} \right)$$ and $${x_2}\left( {{0^ + }} \right)$$ such that $$y\left( t \right) = A{e^{ - 2t}}$$ for t>0