Download PTU (I.K. Gujral Punjab Technical University Jalandhar (IKGPTU) ) BE/BTech EEE (Electrical And Electronics Engineering) 2020 March 4th Sem Electrical Machinery II Previous Question Paper
Roll No. Total No. of Pages : 02
Total No. of Questions : 09
B.Tech.(Electrical & Electronics Engg.) (2013 Onwards)/
B.Tech.(Electronics & Electrical Engg.) (2013 & Onwards)
(Sem.?4)
ELECTRICAL MACHINERY-II
Subject Code : BTEEE-401
M.Code : 72385
Time : 3 Hrs. Max. Marks : 60
INSTRUCTIONS TO CANDIDATES :
1. SECTION-A is COMPULSORY consisting of TEN questions carrying TWO marks
each.
2. SECTION-B contains FIVE questions carrying FIVE marks each and students
have to attempt any FOUR questions.
3. SECTION-C contains THREE questions carrying TEN marks each and students
have to attempt any TWO questions.
SECTION-A
1. Answer briefly :
(a) Define the voltage regulation of a synchronous generator.
(b) Define Pole Pitch of the synchronous generator.
(c) What are the advantages of brushless DC motor?
(d) Define Hunting and oscillations in synchronous machines.
(e) What is the purpose of starters used in three phase induction motor?
(f) By which test synchronous reactance of synchronous machine is determined.
(g) How can the direction of capacitor run motor be reversed?
(h) What is meant by plugging in three phase induction motor?
(i) In what ratio line current and starting torque is reduced with star-delta starting of
three phase induction motor?
(j) What is the specialty of universal motor?
FirstRanker.com - FirstRanker's Choice
1 | M-72385 (S2)-1866
Roll No. Total No. of Pages : 02
Total No. of Questions : 09
B.Tech.(Electrical & Electronics Engg.) (2013 Onwards)/
B.Tech.(Electronics & Electrical Engg.) (2013 & Onwards)
(Sem.?4)
ELECTRICAL MACHINERY-II
Subject Code : BTEEE-401
M.Code : 72385
Time : 3 Hrs. Max. Marks : 60
INSTRUCTIONS TO CANDIDATES :
1. SECTION-A is COMPULSORY consisting of TEN questions carrying TWO marks
each.
2. SECTION-B contains FIVE questions carrying FIVE marks each and students
have to attempt any FOUR questions.
3. SECTION-C contains THREE questions carrying TEN marks each and students
have to attempt any TWO questions.
SECTION-A
1. Answer briefly :
(a) Define the voltage regulation of a synchronous generator.
(b) Define Pole Pitch of the synchronous generator.
(c) What are the advantages of brushless DC motor?
(d) Define Hunting and oscillations in synchronous machines.
(e) What is the purpose of starters used in three phase induction motor?
(f) By which test synchronous reactance of synchronous machine is determined.
(g) How can the direction of capacitor run motor be reversed?
(h) What is meant by plugging in three phase induction motor?
(i) In what ratio line current and starting torque is reduced with star-delta starting of
three phase induction motor?
(j) What is the specialty of universal motor?
2 | M-72385 (S2)-1866
SECTION-B
2. A 3 phase, 50 Hz, 8 pole synchronous generator has a star connected armature winding
with 120 slot and 8 conductors per slot. The flux per pole is 0.05 Wb, sinusoidally
distributed. Determine the phase and line voltages.
3. Explain the construction details of squirrel cage and slip ring rotor induction motor.
Compare the merit and demerit of each type of motor.
4. What is infinite bus? State the characteristics of an infinite bus. What are the operating
characteristics of an alternator connected to an infinite bus?
5. Draw the equivalent circuit of three phase induction motor, also explain torque slip
characteristics.
6. Explain the double field revolving theory used in single phase induction motor.
SECTION-C
7. Explain the working principle of capacitor start single - phase induction motor.
Why should be the auxiliary winding in a capacitor start motor be disconnected after the
motor has picked up speed?
8. A 10kW, 400V, 4 pole delta connected squirrel cage induction motor gave the following
test results :
No-load test : 400V, 8A, 250W
Blocked rotor test : 90V, 35A, 1350W
The dc resistance of the stator winding per phase measured immediately after the blocked
rotor test is 0.6ohm. Calculate the rotational losses and the equivalent circuit parameters.
9. A 3 phase squirrel cage induction motor with an applied voltage of 40% gives a blocked
rotor current of 250% and internal starting torque of 30% of their corresponding rated
values. If an auto transformer limits the starting line current to 150% of the motor full
load current, compute the percentage starting torque.
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.
FirstRanker.com - FirstRanker's Choice
This post was last modified on 21 March 2020