Download PTU (I.K.Gujral Punjab Technical University (IKGPTU)) B-Tech (Bachelor of Technology) (EEE)- Electrical And Electronics Engineering 2020 December 3rd Sem 72163 Asynchronous Machines Previous Question Paper
Roll No.
Total No. of Pages : 02
Total No. of Questions : 18
B.Tech. (EE) PT (Sem.?3)
ASYNCHRONOUS MACHINES
Subject Code : BTEE-401
M.Code : 72163
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 questio ns.
3 .
SECT ION-C contains THREE questions carrying T EN marks e ach and s tudents
have to atte mpt ANY TWO questions .
SECTION-A
Answer briefly :
Q1
Give analogy between transformer and three phase induction motor.
Q2
State Lenz law.
Q3
How iron losses in machines can be reduced?
Q4
What is purpose of using deep bar cage rotors?
Q5
What is working principle of shaded pole induction motor?
Q6
Why induction motor draws heavy current as compared to full load current at starting?
Q7
What is the use of slip ring induction motor?
Q8
Give the applications of capacitor start single phase induction motor.
Q9
What is cogging?
Q10
What is the use of double cage induction motors?
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SECTION-B
Q11
Describe the construction of a double cage induction motor. Explain its working.
Q12
Draw and Explain the push button operated DOL starter.
Q13
Explain the working principle of a single phase induction motor with the help of double
Revolving field theory.
Q14
Explain the construction & working of universal motor.
Q15
Why an induction generator is not a self-excited generator? How does an isolated
induction generator works?
SECTION-C
Q16
A 3-phase induction motor has a 4 pole, Y connected staor winding. The motor runs on
50Hz Supply with 200V between lines. The motor resistance and standstill reactance per
phase are 0.1 ohm and 0.9 ohm respectively, is equal to. Calculate the maximum torque
& the starting torque.
Q17
Explain the different speed control methods used in three phase induction motors.
Q18
Explain the procedure of no load test and blocked rotor test on a three phase induction
motor. How are the parameters of equivalent circuit determined from test results?
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