Download AKTU B-Tech 4th Sem 2014-15 Electric Machine and Automatic Contro Question Paper

Download AKTU (Dr. A.P.J. Abdul Kalam Technical University (AKTU), formerly Uttar Pradesh Technical University (UPTU) B-Tech 4th Semester (Fourth Semester) 2014-15 Electric Machine and Automatic Contro Question Paper

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Printed Pages : 4
a 12-161 3 "
N EE?409
Roll . N 9;
(Following Paper 1]) and Roll No. to be ?lled in your Answer Book)
PAPER ID : 121413
Time : 3 Hours]
1 Attempt any four of the following :
B. Tech.
(SEM. IV) THEORY EXAMINATION, 2014-15
ELECTRIC MACHINE & AUTOMATIC CONTROL
[Total Marks ; 100
4X 5=20
(a) Explain the different speed control methods used in a
DC motor.
(b) Discuss conversion from 3 phns? to thase using Scott
connection.
(c) Brie?y enumerate the working of auto transformer with
its merits, demerits.
(d) A 10 kva single phase 500/250 v transformer gave
followingtest.
00 TEST 250V 3A 200W
SCTEST 15V 30A 300w
Find e?iciency and regulaton at full load 0.8 p.f. Lagging ?
0
121413]
1
[ Contd...

(e) Why series motor is never start on no load, also explain
application of DC series and shunt motor.
(1) Why starter is required in DC motor ? Explain different
method o'fstarting.
2 Attempt any two of the following : 1 lOXZ=20
(a) ' (i) Explain the working principle of 3-phase induction
motor. The rotor of induction motor cannot run
at synchronous speed. Explain. Why ?
(1i) 3-d) induction motor is wound for 4 poles and
is supplied from 50 Hz system Calculate
(a) synchronous speed
(b) rotor speed when slip is 4% and
(c) rotor ?equency when rotor?runs at
600 rpm
(b) Explain the working of two phase servo motor and their
application.
(0) Explain the following :
(1) Synchronizing, of altemators
Oi) V-curve of synchronous motor
3 Attempt any two of the following : 10X2=20
(a) Compare open loop and closed loop system with
suitable examples.
121413] 2 [ Contd...
(b) Obtain di?erential equation describing" equivalent
mechanical system of ?g. 1 and draw the equivalent
F?V analogy.
'Kn <3: ? E_,_I 31 _ +? ?QT. 9+
, _,,..?> ~. "I 'm l,
.,
Fig. 2
(c) What do you mean by Transfer Function; ?nd out
Transfer Function for Fig. 2 circuit.
4 Attempt any two of the following ; 10><2=20
(a) . Find out steady type en?or with unit step, ramp and
parabolic input for
(1) type zero
(1i) type one
(111) type two system
(b) (1) Explain bounded i/p bounded o/p stability criterion.
(1i) Find stability condition for following chmcte?slics
equatign
s3 + 2ks2 + (k+2)*s + 4=0
121413] 3 [ Contd...

(c) Draw polar plot for G(s) = K / (sA + l)*(sB+1) for
unity feedback system, ?nd Gain maggin, phase margin.
5 'Attempt any two of the following : V 10X2=20
(a) Draw bode plot and determine GM, P.M., comment
on stability.
G(s) H(s) = 16 (1+o.5s)/ s2 * (1+o.125s) *(1+o.1s)
(b) Explain the Proportional, Derivate, Integral controller
and write their advantages.
(c) construct root locus for
G (s) H (s)~= k/s* (3+4) * (5+5) K > 0
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