Download PTU B-Tech EEE 2020 Dec 3rd Sem 76465 Electrical Machines I Question Paper

Download PTU (I.K.Gujral Punjab Technical University (IKGPTU)) B-Tech (Bachelor of Technology) (EEE)- Electrical And Electronics Engineering 2020 December 3rd Sem 76465 Electrical Machines I Previous Question Paper

Roll No.
Total No. of Pages : 02
Total No. of Questions : 18
B.Tech. (Electrical & Electronics Engg. / Electronics & Electrical Engg.)
(2018 Batch) (Sem.?3)
ELECTRICAL MACHINES-I
Subject Code : BTEEE-303-18
M.Code : 76465
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
Write briefly :
1.
What is the importance of Magnetic Circuits? Explain.
2.
Explain briefly the effect of permeability of materials on the magnetic flux density.
3.
What is the significance of flux per pole? Explain.
4.
Discuss the significance of torque in electrical machines.
5.
What do you mean by back emf? Explain.
6.
Explain the need of three winding transformers.
7.
What do you mean by Bar Magnet? Discuss.
8.
Explain the term Critical Field Resistance.
9.
What do you mean by Tap Changing Transformers? Explain.
10. Explain the term efficiency w.r.t. transformers.
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SECTION-B
11. Explain the following terms in detail :
a) MMF
b) Flux
c) Reluctance
d) Inductance
12. Discuss (in detail) the working principle and construction of a single-phase transformer.
Also discuss its equivalent circuit and phasor diagram.
13. Explain :
a) Difference between Lap and Wave winding.
b) Induced EMF in an armature coil.
14. Discuss the parallel operation of three phase transformers.
15. Discuss the open circuit characteristics of separately excited DC generator.
SECTION-C
16. Explain :
a) Auto-transformers
b) Scott connection of transformers
17. Explain the VI characteristics and torque speed characteristics of separately excited, shunt
and series motors.
18. Explain the following :
a) Construction of DC machines
b) Magnetic flux lines and influence of highly permeable materials on the magnetic flux
lines.
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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