B.TechSemester 52023-24Electrical Machines IiKEE503

Electrical Machines Ii (KEE503) - AKTU Question Paper 2023-24

B.Tech · Semester 5 · Free PDF Download

This is the official AKTU Electrical Machines Ii Previous Year Question Paper for B.Tech Semester 5, academic session 2023-24. Published by Dr. A.P.J. Abdul Kalam Technical University (AKTU/UPTU), Lucknow. Free PDF download — no login required.

Course:B.Tech
Semester:Semester 5
Session:2023-24
University:AKTU / UPTU

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Questions Asked in 2023-24

Electrical Machines Ii (KEE503) — complete question paper · 100 marks · 3 Hours

Section AAttempt all q u e s t i o n s i n b r i e f . 2 x 10 = 20
  • a
    A 6-pole alternator rotates at 1000rpm. What is the frequency of the generated voltage?
  • b
    Name the various methods for predetermining the voltage regula tion of 3-phase Alternator
  • c
    What are the V-curves of a synchronous motor? 2 2
  • d
    Enlist the conditions for paral lel operation of two single-pha se alternators
  • e
    Why the slots in the rotor of an induction motor are usually skewed? 2 3
  • f
    What is the condition for produci ng maximum torque in a 3-phas e induction motor?
  • g
    Define cogging in an in duction motor. 2 4
  • h
    Why the power factor of an induc tion motor is low at starting? 2 4 i. List the different types of si ngle-phase induction motors. 2 5 j. Suggest modifications to be made in a dc series motor to opera te it satisfactorily on alternating current?
Section BAttempt any three o f t h e f o l l o w i n g : 10 x 3 = 30
  • a
    Why is rotating field system used in preference to a station ary field? Describe the difference in construction of rotors of alternator s used in hydroelectric plants and steam pla nts. Draw neat sketches of th e two types of rotor
  • b
    Explain working principle of synchronous motor. Discuss how synchronous motor is started using damper winding
  • c
    A 6-pole, 50 Hz, 3-phase induc tion motor has resistance and reactance of 0.5 Ω and 5 Ω per phase respectively. Calculate (i) at what spe ed the torque is maximum (ii) the ratio Maximum torque / starting torq ue. Determine the external resistance per phase to be inserted so that starting torque is half of the maximum torque
  • d
    Describe star-delta and autotr ansformer method of starting o f 3-phase induction motor
  • e
    Explain the working and construction of (i) shaded pole moto r and (ii) Permanent-split Capacitor motor
Section CAttempt any one p a r t o f t h e f o l l o w i n g : 10x1 = 10
  • a
    A 3-phase, 16 pole, star-conne cted alternator is running at 375 rpm. The stator has 2 slots per pole per phase and 4 conductors per slot accommodated in two layers. The coil span is 150 degrees-electr ical. Determine useful flux per pole if the machine gives phase volta ge of 795.3 V on open circuit
  • b
    Derive emf equation for synchr onous generator. Also, derive and incorporate pitch factor and distribution factor in the emf equation
  • a
    Two identical 2 MVA synchronous generators are operating in parallel. The governor of the first machine is such that the frequency dr ops from 50 Hz on no-load to 48 Hz on full load and the corresponding un iform frequency drop of second machine from 50 Hz to 47.5 Hz (a) Dete rmine how will the machine share a load of 3000 kW? (b) Determine wha t is the maximum load at unity power factor that can be delivered wi thout overloading either machine
  • b
    Explain hunting in synchronous m otor. What are its causes and remedy? 10 2
  • a
    Derive and draw the torque-slip characteristics of a 3-phase induction motor indicating starting, maximum torque and the operating region
  • b
    A 4-pole, 440V 3-phase induction motor runs at 1450 rpm at 0 .85 pf developing 11 kW power. The st ator losses are 1100 W and mechan ical losses are 400 W. Determine (i) slip (ii) rotor copper loss (ii i) rotor frequency (iv) line current (v) efficiency
  • a
    Explain (i) Consequent pole me thod and (ii) V/f method for s peed control of 3-phase induction motor
  • b
    Determine the maximum permis sible full load kVA of the 3-ph ase induction motor if the supply current drawn from a 400 V, 50 Hz , 3- phase supply is 120A. The starting current is 6 times full load current, when (i) it is directly connected to the mains (ii) it is conn ected through an autotransformer with a tapping of 60% and (iii) it is design ed for use with star delta starter
  • a
    Discuss blocked rotor test and no-load test of single phase ind uction motor
  • b
    Explain the working of double cage motor induction motor. Al so, draw and describe its equivalent circuit diagram

Question text is extracted from the official AKTU question paper PDF above. Hindi translations are omitted — every question is printed in English in the original paper. Last verified: 2026-08-23.

Repeated Questions — KEE503

Questions that appeared in more than one session, found by comparing 3 years of Electrical Machines Ii papers (2021-22, 2022-23, 2023-24)

3x

Define cogging in an in duction motor. 2 4

Appeared in: 2021-22 · 2022-23 · 2023-24

3x

Derive emf equation for synchr onous generator. Also, derive and incorporate pitch factor and distribution factor in the emf equation

Appeared in: 2021-22 · 2022-23 · 2023-24

2x

What are the V-curves of a synchronous motor? 2 2

Appeared in: 2022-23 · 2023-24

2x

Explain the working and construction of (i) shaded pole moto r and (ii) Permanent-split Capacitor motor

Appeared in: 2022-23 · 2023-24

2x

Derive and draw the torque-slip characteristics of a 3-phase induction motor indicating starting, maximum torque and the operating region

Appeared in: 2022-23 · 2023-24

Electrical Machines Ii — Other Year Papers

AKTU Electrical Machines Ii PYQs from other sessions