M.Sc. (Semester II) (CBCS) Examination Mar/Apr-2018
Electronic Science
CONTROL SYSTEMS
Time 2½ Hours
Max. Marks: 70
Instructions: Q.1 and Q.2 are compulsory. Attempt any three questions from Q.3 to Q.7. All questions carry equal marks. Use of nonprogrammable calculator is allowed.
Q.1

Select the correct alternatives:-
08
A system with gain margin close to unity or a phase margin close to zero is
highly stable
oscillatory
relatively stable
unstable
Which condition is used to verify the existence of a particular point on the root locus?
amplitude
frequency
magnitude
angle
Which among the following are the elements of rotational motion?
Mass, spring, friction
Inertia, damper, spring
Work, energy, power
Force, pressure, viscosity
In the P-D controller, the derivative action plays a significant role in increasing of response.
time
distance
speed
volume
A system obeys the principle of superposition.
Linear
Non-linear
Static
Dynamic
The root locus is
An algebraic method
A graphical method
Combination of both
None of these
From Routh's criterion all the terms in the column of Routh's array must have same sign.
first
second
third
fourth
If there are repeated roots of the characteristics equation are on the imaginary the system is
stable
unstable
oscillatory
conditionally stable
Q.1

State true and false
06
Settling delay time is frequency domain specification.
The ramp signal is used as standard test signals for time domain studies.
Bode plot represent the two separate plots of magnitude and phase against frequency in logarithmic value.
Page 2 of 2
SLR-UH-299
The fundamental function of a tachogenerator is the conversion of rotational speed into proportional voltage.
By equating the denominator of transfer function to zero, poles will be obtained.
In mechanical translational system force is replaced by voltage in electrical system.
Q.2
Attempt the following:-
A)Explain stability analysis using Routh's criterion.
05
B)Explain DC tachogenerator and represent in block diagram form.
05
C)Describe the concept of poles and zeroes.
04
Q.3
A)Draw and explain RLC circuit and obtain its transfer function.
08
B)Reduce the following diagram and obtain its transfer function.
06
Q.4
A)Design and calculate the transfer function for the following compensator:
Lead compensator
Lag compensator
10
B)Write a note on classifications of control system.
04
Q.5
A)Consider unity feedback system with Obtain its roots locus.
08
B)Determine the stability of a given characteristic equation by Routh's method: S3 6S2 11S 6 0 is characteristic equation.
06
Q.6
A)Explain the time response of second order system subject to unit step input for the following cases:
under-damped
critically damped
10
B)List the advantages and disadvantages of P controller.
04
Q.7
A)Explain the state space representation for the following:
Electrical Network
nth order differential equation
10
B)Compare Open loop system and closed system
04