OM ENGINEERING COLLEGE, JUNAGADH
QUESTION BANK
ELECTRICL ENGINEERING DEPARTMENT
SUBJECT :-EED(2150904)
QUSTION
NUMBER CH.:-1 Fundamental of Magnetic
Circuit.
1 Explain various methods for calculating the mmf required for tapered
*** teeth. ( JAN.-2013,JUNE-2011)
2 What is Carter’s fringing curves? Discuss its application.
3 Define and clearly explain the terms: (1) Gap contraction factor for slots
*** and ducts (2) Stacking factor (3)Field form factor
(JUNE-2011,JUNE-2012)
4 Define real and apparent flux densities in the tooth of a d.c machine
******* armature. Explain difference between them and also derive relation
between them.
(DEC.-2013,JAN.-2013,NOV.-2011,JUNE-2011,MAY-2013)
5 Derive an expression of reluctance of an air gap in d.c. machine. Explain
clearly the effects of (1) Slotting and (2) Ventilating ducts.
(JUNE-2014)
6 What is carter’s coefficient? How does it help in estimation of mmf in
******* case of slotted armature? What are the expressions to be used for
estimation ?
(DEC.-2010,NOV.-2011,MAY-2013, JUNE-2014)
CH.:-2 Design of Starters, Field Regulators
7 Write a short note on field regulator.
******* Or
Explain the design procedure to design a field regulator to change the
EMF generated in a self-excited dc generator.
(DEC.-2013,DEC.-2010,JUNE-2012,MAY-2013)
8 Prove that the section resistances of DC shunt motor starters are in
geometrical progression.
OR
Derive the steps for calculate the starter resistance for D.C shunt motor.
(JAN.-2013)
9 Describe at least two important components of a simple control panel
*** for a three phase induction motor. (DEC.-2013,DEC.-2010)
10 Explain with neat sketch power and control circuit of Direct On Line
***** Starter. (DEC.-2013,JUNE-2012)
11 With neat sketch explain power and control circuit diagram of a star
delta starter. (JUNE-2014)
12 Show that section resistances of three phase slip ring induction motor
starter in geometric progression. (JUNE-2014)
13 Draw main circuit and control circuit of star delta starter for sq cage
induction motor. (JAN.-2013)
CH.:-3Design of small Transformers and
Choke coils.
14 Derive expressions for the weight of active iron and copper in case of a
single phase transformer in terms of core dimensions and winding
diameters. (DEC.-2010)
15 Discuss design procedure of single phase small transformer.
******* (JAN.-2013,NOV.-2011,JUNE-2012,MAY-2013, JUNE-2014)
16 How does the design procedure differ from a fixed core design to a
variable air-gap rector design? (DEC.-2010)
17 Explain the selection of the flux density in case of a variable air-gap
reactor from the fundamentals. (DEC.-2010)
18 Give complete procedural steps for designing single phase variable
******* choke coil for given supply voltage, air-gap variation and current
variation. (DEC.-2012,NOV.-2011,JUNE-2012)
19 Explain the design procedure of a 3-phase variable choke coil.
***** (JUNE-2011,MAY-2013)
20 What are the functions of welding transformer? Give the steps for
*** designing reactor for welding transformer. (JUNE-2012)
21 Discuss design procedure for welding transformer.
***** (JAN.-2013, JUNE-2014)
CH.:-4 Armature Windings
22 Explain the use of dummy coils and equalizer connections in d.c.
******* armature windings. Also explain why equalizer connections are not
necessary in case of wave windings?
OR
What do you mean by “dummy coil”? What is its application? Also
explain the use of equalizer connections in DC armature winding.
(NOV-2011,JUNE-2011, JUNE-2014)
23 Differentiate clearly between a mush winding and a double layer
***** winding for three phase ac machines.
(DEC.-2010,MAY-2013)
24 Differentiate between integral and fractional slot windings also state
*** advantages of fractional slot windings.
OR
What is fractional slot winding? Discuss its advantages.
(NOV.-2011,JUNE-2011)
25 With suitable diagram explain the terms with respect to a.c. armature
*** winding. (1) Phase spread (2) Chorded winding (3) Coil span (4) Full
pitch coils. (5) Coil (6)Turn
(JAN.-2013,JUNE-2014)
CH.:-5 Estimating Costing for Residential,
Commercial &Service Connections (1- ø &3-ø)
26 Write all steps to estimate the total cost of electric wiring installation for
Building. (JAN.-2013)
27 Explain the design procedure for electrification of a small industry
******* having a load of about 50 KW and a shade area of about 1100 m2.
(DEC.-2013)
CH.:-6 Design consideration of Electrical
Installation
28 Explain load assessment and permissible voltage drop for electric
***** installations.
(JAN.-2013,JUNE-2014)
29 Describe and compare the different systems of wiring used for domestic
******* installations.
(DEC.-2013,NOV.-2011,JUNE-2012,MAY-2013,JUNE-2014)
30 What is electric load? Giving examples classify different types of load
***** (NOV.-2011,JUNE-2011,MAY-2013)
31 Discuss the factors that should be considered while selecting the type of
a wiring system. (JUNE-2011)
32 Write all steps to estimate the total cost of electric wiring installation for
building . (JAN.-2013)
33 Explain a typical 3- Φ , 4 -wire supply system. (JUNE-2012)
