Download PTU (I.K.Gujral Punjab Technical University (IKGPTU)) B-Tech (Bachelor of Technology) (EEE)- Electrical And Electronics Engineering 2020 December 4th Sem 57105 Linear Control Systems Previous Question Paper
Roll No.
Total No. of Pages : 03
Total No. of Questions : 18
B.Tech. (Electronics Engg/ECE/Electronics & Electrical Engg/Electrical
Engineering & Industrial Control/Electronics & Computer Engg)
(2012 to 2017)/B.Tech.(EE/Electrical & Electronics Engg.)
(2012 Onwards) (Sem.?4)
LINEAR CONTROL SYSTEMS
Subject Code : BTEE-402
M.Code : 57105
Time : 3 Hrs. Max. Marks : 60
INST RUCT IONS T O CANDIDAT ES :
1 .
SECT ION-A is COMPULSORY cons is ting of TEN questions carrying TWO marks
each.
2 .
SECT ION-B c ontains F IVE questions c arrying FIVE marks eac h and s tud ents
have to atte mpt any FOUR q ues tions.
3 .
SECT ION-C contains THREE questions carrying T EN marks e ach and s tudents
have to atte mpt any T WO questio ns.
SECTION-A
Answer briefly :
1.
Explain the importance and need of compensation.
2.
Find the restriction of K so that closed loop system given by the following characteristic
equation is absolutely stable.
s3 + 2 Ks2 + (K + 2)s + 4 = 0
3.
Define Nyquist criterion.
4.
Explain the effect of on the output response of any system.
5.
Differentiate between break away and break in points.
6.
Describe the output response of type-I and type-II systems for ramp input.
7.
Derive the mathematical model of a series RLC circuit.
8.
Evaluate the static error coefficients for unit step input for the system having :
20
G(s)
2
s(s 2)(s 2s 20)
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9.
Give the F-V and F-I analogy for the following system :
K1
K2
B2
F(t)
M1
M
M
2
3
B1
K3
10. Explain the effect of the location of poles on the stability of any system.
SECTION-B
11. Derive the frequency domain specifications Mr and r for a second order system and
correlate them with their time domain specifications.
12. For the system represented by the given equations find C/R using SFG technique only.
X2 = G1X1 ? HlX3 ? H2X4 ? H3X5
X3 = G2X2 ? H4X5
X4 ? G3X3 + G5X4
X5 = G4X3 + G6X4
13. A unity feedback system having open loop transfer function as :
K (s 1)
G(s)
3
2
s as 2s 1
System oscillates with frequency . Determine the values of `K' and `a' so that the
system oscillates at a frequency of 2 rad/sec.
14. The open loop transfer function of a unity feedback control system is :
K
G(s) =
s(1 sT )
By what factor the amplifier gain K should be reduced so that Mp of unit step response of
the system is reduced from 80% to 30%?
15. Write a short note on working of synchros as error detector.
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SECTION-C
16. Construct the bode plot for the system whose open loop transfer function is given below
and determine (a) gain margin (b) phase margin (c) closed loop stability.
512(s 3)
G(s) H(s)
2
s(s 16s 256)
17. Sketch the root locus for the open-loop transfer function of a unity feedback control
system given below and find : (a) value of K for marginal stability (b) frequency of
oscillations.
K
G(s)
2
s(s 4s 8)
18. State the necessity of compensation. Derive the transfer function of phase lead and phase
lag compensator along with the circuit diagrams and state the advantages and limitations.
NOTE : Disclosure of Identity by writing Mobile No. or Making of passing request on any
page of Answer Sheet will lead to UMC against the Student.
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This post was last modified on 13 February 2021