Control Systems
Signal Flow Graph and Block Diagram
Marks 1Marks 2Marks 5
Basic of Control Systems
Marks 1Marks 2
Frequency Response Analysis
Marks 1Marks 2Marks 5Marks 8Marks 10
Root Locus Diagram
Marks 1Marks 2
State Space Analysis
Marks 1Marks 2Marks 5Marks 10
1
GATE ECE 2025
MCQ (Single Correct Answer)
+2
-0.67

Consider a system where $x_1(t), x_2(t)$, and $x_3(t)$ are three internal state signals and $u(t)$ is the input signal. The differential equations governing the system are given by

$$ \frac{d}{d t}\left[\begin{array}{l} x_1(t) \\ x_2(t) \\ x_3(t) \end{array}\right]=\left[\begin{array}{ccc} 2 & 0 & 0 \\ 0 & -2 & 0 \\ 0 & 0 & 0 \end{array}\right]\left[\begin{array}{l} x_1(t) \\ x_2(t) \\ x_3(t) \end{array}\right]+\left[\begin{array}{l} 1 \\ 1 \\ 1 \end{array}\right] u(t) $$

Which of the following statements is/are TRUE?

A
The signals $x_1(t), x_2(t)$, and $x_3(t)$ are bounded for all bounded inputs.
B
There exists a bounded input such that at least one of the signals $x_1(t), x_2(t)$, and $x_3(t)$ is unbounded.
C
There exists a bounded input such that the signals $x_1(t), x_2(t)$ and $x_3(t)$ are unbounded.
D
The signals $x_1(t), x_2(t)$ and $x_3(t)$ are unbounded for all bounded inputs.
2
GATE ECE 2024
MCQ (More than One Correct Answer)
+2
-0

Consider a system $S$ represented in state space as

$$\frac{dx}{dt} = \begin{bmatrix} 0 & -2 \\ 1 & -3 \end{bmatrix}x + \begin{bmatrix} 1 \\ 0 \end{bmatrix}r , \quad y = \begin{bmatrix} 2 & -5 \end{bmatrix}x.$$

Which of the state space representations given below has/have the same transfer function as that of $S$?

A

$$\frac{dx}{dt} = \begin{bmatrix} 0 & 1 \\ -2 & -3 \end{bmatrix}x + \begin{bmatrix} 0 \\ 1 \end{bmatrix}r , \quad y = \begin{bmatrix} 1 & 2 \end{bmatrix}x.$$

B

$$\frac{dx}{dt} = \begin{bmatrix} 0 & 1 \\ -2 & -3 \end{bmatrix}x + \begin{bmatrix} 1 \\ 0 \end{bmatrix}r , \quad y = \begin{bmatrix} 0 & 2 \end{bmatrix}x.$$

C

$$\frac{dx}{dt} = \begin{bmatrix} -1 & 0 \\ 0 & -2 \end{bmatrix}x + \begin{bmatrix} -1 \\ 3 \end{bmatrix}r , \quad y = \begin{bmatrix} 1 & 1 \end{bmatrix}x.$$

D

$$\frac{dx}{dt} = \begin{bmatrix} -1 & 0 \\ 0 & -2 \end{bmatrix}x + \begin{bmatrix} 1 \\ 1 \end{bmatrix}r , \quad y = \begin{bmatrix} 1 & 2 \end{bmatrix}x.$$

3
GATE ECE 2018
MCQ (Single Correct Answer)
+2
-0.67
The state equation and the output equation of a control system are given below:

$$\mathop x\limits^. = \left[ {\matrix{ { - 4} & { - 1.5} \cr 4 & 0 \cr } } \right]x + \left[ {\matrix{ 2 \cr 0 \cr } } \right]u,$$

$$y = \left[ {\matrix{ {1.5} & {0.625} \cr } } \right]x.$$

The transfer function representation of the system is
A
$${{3s + 5} \over {{s^2} + 4s + 6}}$$
B
$${{3s - 1.875} \over {{s^2} + 4s + 6}}$$
C
$${{4s + 1.5} \over {{s^2} + 4s + 6}}$$
D
$${{6s + 5} \over {{s^2} + 4s + 6}}$$
4
GATE ECE 2017 Set 2
MCQ (Single Correct Answer)
+2
-0.6
A second order LTI system is described by the following state equation. $$$\eqalign{ & {d \over {dt}}{x_1}\left( t \right) - {x_2}\left( t \right) = 0 \cr & {d \over {dt}}{x_2}\left( t \right) + 2{x_1}\left( t \right) + 3{x_2}\left( t \right) = r\left( t \right) \cr} $$$

When x1(t) and x2(t) are the two state variables and r(t) denotes the input. The output c(t)=X1(t). The systyem is

A
undamped (oscillatory)
B
under damped
C
critically damped
D
over damped
GATE ECE Subjects
Signals and Systems
Network Theory
Control Systems
Digital Circuits
General Aptitude
Electronic Devices and VLSI
Analog Circuits
Engineering Mathematics
Microprocessors
Communications
Electromagnetics