EE3303-EM-I-CP.pdf

FORMAT : QP09 KCE/DEPT.OF EEE
EM-I 5.1 KCE / EEE / QB / II-YR / EM-I
DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING
SUBJECT NAME : ELECTRICAL MACHINES – I
YEAR / SEMESTER: II /III
QUESTION BANK (EE3303)
(Version: 1)
PREPARED BY
Dr. P. NARASIMMAN, AP/ EEE

Format : QP09 KCE/DEPT.OF EEE
EE8301 ELECTRICAL MACHINES – I
UNIT I ELECTROMECHANICAL ENERGY CONVERSION 9
Fundamentals of Magnetic circuits- Statically and dynamically induced EMF - Principle of
electromechanical energy conversion forces and torque in magnetic field systems- energy
balance in magnetic circuits- magnetic force- co-energy in singly excited and multi excited
magnetic field system mmf of distributed windings – Winding Inductances-, magnetic fields in
rotating machines- magnetic saturation and leakage fluxes. Introduction to Indian Standard
Specifications (ISS) - Role and significance in testing.
UNIT II DC GENERATORS 9
Principle of operation, constructional details, armature windings and its types, EMF equation,
wave shape of induced emf, armature reaction, demagnetizing and cross magnetizing Ampere
turns, compensating winding, commutation, methods of improving commutation, interpoles,
OCC and load characteristics of different types of DC Generators. Parallel operation of DC
Generators, equalizing connections- applications of DC Generators.
UNIT III DC MOTORS 9
Principle of operation, significance of back emf, torque equations and power developed by
armature, speed control of DC motors, starting methods of DC motors, load characteristics of DC
motors, losses and efficiency in DC machine, condition for maximum efficiency. Testing of DC
Machines: Brake test, Swinburne’s test, Hopkinson's test, Field test, Retardation test, Separation
of core losses-applications of DC motors.
UNIT IV SINGLE PHASE TRANSFORMER 9
Construction and principle of operation, equivalent circuit, phasor diagrams, testing - polarity
test, open circuit and short circuit tests, voltage regulation, losses and efficiency, all day
efficiency, back-to back test, separation of core losses, parallel operation of single-phase
transformers, applications of single-phase transformer.
UNIT V AUTOTRANSFORMER AND THREE PHASE TRANSFORMER 9
Construction and working of auto transformer, comparison with two winding transformers,
applications of autotransformer. Three Phase Transformer- Construction, types of connections
and their comparative features, Scott connection, applications of Scott connection.
SIGNATURE OF STAFF IN-CHARGE HOD/EEE
L T P C
3 0 0 3

: 2021-2025
: 2022-23 (Odd)
Batch
Academic Year
Branch / Year / Sem: B.E EEE / II / III
: EE3303
: Electrical Machines - I
: Dr.P.Narasimman
Sub. Code
Sub. Name
Staff Name
DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING
COURSE PLAN
COURSE OBJECTIVE
To impart knowledge on the following topics
• Concept of electromechanical energy conversion system.
• Appropriate machine for a given application based on its characteristics.
• Appropriate test to determine the performance parameters of a given machine.
• Procedure for parallel operation of generators and transformers.
• Working of auto transformer and three phase transformers.
TEXT BOOKS
T1. I. J. Nagrath and D. P. Kothari, “Electric Machines”, McGraw Hill Education, 5th Edition,
2017.
T2. P. S. Bimbhra, “Electric Machinery”, Khanna Publishers, 2nd Edition, 2021.
REFERENCE BOOKS
R1. A. E. Fitzgerald and C. Kingsley, "Electric Machinery”, New York, McGraw Hill Education,
6th Edition 2017.
R2. Sahdev S. K, “Electrical Machines”, Cambridge University Press, 2018.
WEB RESOURCES
W1. https://www.bis.gov.in/index.php/the-bureau/about-bis/ (Topic No:06)
W2. https://nit-edu.org/wp-content/uploads/2021/09/ch-27-Armature-reaction-and-
commutation.pdf (Topic No:10)
W3. https://nit-edu.org/wp-content/uploads/2021/09/ch-31-Testing-of-dc
machines.pdf (Topic No:20)
W4. https://www.elprocus.com/what-is-a-single-phase-transformer-construction-and-
its-working/ (Topic No:22)
W5. https://www.elprocus.com/what-is-an-auto-transformer-construction-and-its-
working/ (Topic No:29)
W6. https://nptel.ac.in/courses/108105017 (Topic No:23)

Topic
No.
Topic Books for
Reference
Page
No.
Teaching
Methodology
No. of
Periods
Required
Cumulative
No. of
periods
UNIT I ELECTROMECHANICAL ENERGY CONVERSION (9+1)
01 Fundamentals of Magnetic
circuits - Statically and
dynamically induced EMF
R1
R2
1-56
28-34
BB/PPT 1 1
02 Principle of electromechanical
energy conversion forces and
torque in magnetic field
systems
T2 160-164 BB/PPT 2 3
03 Energy balance in magnetic
circuits- magnetic force R1 117-119 VIDEO 1 4
04 Co-energy in singly excited and
multi excited magnetic field
system mmf of distributed
windings – Winding
Inductances
R1 119-151 VIDEO 2 6
05 Magnetic fields in rotating
machines – magnetic
saturation and leakage fluxes
T1 279-282 BB/PPT 2 8
06 Introduction to Indian
Standard Specifications (ISS)
W1 -
BB/PPT
1 9
07 Role and significance in testing.
BB/PPT 1 10
LEARNING OUTCOME
At the end of unit, students should be able to
• Learn the principle of electromechanical energy conversion.
• Understand magnetic circuits and methods of analysis, flux linkage, inductance.
• Explain about statically and dynamically induced emf.
• Understand the Indian Standard Specifications (ISS) and role and significance in testing.
UNIT II DC GENERATORS (9+1)
08 Principle of operation,
constructional details
R2 301-307 BB/PPT 2 12
09
Armature windings and its
types, EMF equation
T1
324-330
340-341
VIDEO 2 14
10 Wave shape of induced emf,
armature reaction
W2 -
BB/PPT
NPTEL
1 15
11 Demagnetizing and cross
magnetizing Ampere turns,
compensating winding
T2 398-402 BB/PPT 1 16
12 Commutation, methods of
improving commutation,
interpoles
T1 358-366 BB/PPT 1 17
13 OCC and load characteristics of
different types of DC
Generators
T2 407-428 VIDEO 1 18

Topic
No. Topic
Books for
Reference
Page
No.
Teaching
Methodology
No. of
Periods
Required
Cumulative
No. of
periods
14 Parallel operation of DC
Generators
T1 399-403 BB/PPT 1 19
15
Equalizing connections-
applications of DC Generators.
R2 381-382 BB/PPT 1 20
LEARNING OUTCOME
• Understand the construction of D.C machine, different windings, their merits and demerits.
• Analyze different types of DC generators their characteristics, industrial applications and effect of
armature reaction.
• Intrept the various losses in DC machines and their efficiency.
UNIT III DC MOTORS (9+1)
16 Principle of operation,
significance of back emf
R2 395-398 BB/PPT 1 21
17 Torque equations and power
developed by armature
R2 398-401 BB/PPT 1 22
18 speed control of DC motors,
starting methods of DC motors,
load characteristics of DC
motors
T1 403-453 VIDEO 2 24
19 Losses and efficiency in DC
machine, condition for
maximum efficiency
T2 489-492 BB/PPT 2 26
20 Testing of DC Machines: Brake
test, Swinburne’s test,
Hopkinson's test, Field test,
Retardation test, Separation of
core losses
W3
T1
-
457 -469
BB/PPT 3 29
21 Applications of DC motors T1 476-477 VIDEO 1 30
LEARNING OUTCOME
• Describe the fundamental operating principles of a DC motor.
• Explain the operation of various DC motor starters and speed controls.
• Outline the torque current characteristics of different types of DC motors.
• Acquire knowledge about testing and applications of dc machines.
UNIT IV SINGLE PHASE TRANSFORMER (9+1)
22 Construction and principle of
operation
W4
R2
-
80-93
BB/PPT 1 31
23 Equivalent circuit, phasor
diagrams
T2
W6
10-26
BB/PPT
NPTEL
2 33
24
Testing - polarity test, open
circuit and short circuit tests R2 158-167 VIDEO 2 35
25 Voltage regulation, losses and
efficiency, all day efficiency T2 40-66 BB/PPT 2 37

Topic
No.
Topic Books for
Reference
Page
No.
Teaching
Methodology
No. of
Periods
Required
Cumulative
No. of
periods
26 back-to back test, separation of
core losses R2 167-179 BB/PPT 1 38
27 Parallel operation of single-
phase transformers
T2 84-100 BB/PPT 1 39
28 Applications of single-phase
transformer.
T1 147-153 VIDEO 1 40
LEARNING OUTCOME
• Identify the physical components of transformer.
• Determine and interpret efficiency and regulation of a single phase transformer.
• Analyze the performance of single phase transformers.
• Understand features and their industrial applications.
UNIT V AUTOTRANSFORMER AND THREE PHASE TRANSFORMER (9+1)
29 Construction and working of
auto transformer
W5
R2
-
195-198
VIDEO 3 42
30 Comparison with two winding
transformers, applications
of autotransformer
R2 224-225 VIDEO 1 44
31 Three Phase Transformer-
Construction
R2 225-227 BB/PPT 2 46
32 types of connections and their
comparative features
T2 129-134 BB/PPT 2 48
33 Scott connection, applications
of Scott connection
R2 275-277 BB/PPT 2 50
LEARNING OUTCOME
• Understand the construction of auto transformer and three phase transformer.
• Identify the physical components of three phase transformer.
• Learn the different types of three-phase transformer connection.
COURSE OUTCOME
At the end of the course, the students will be able to
• Apply the laws governing the electromechanical energy conversion for singly and multiple
excited systems.
• Explain the construction and working principle of DC machines.
• Interpret various characteristics of DC machines.
• Compute various performance parameters of the machine, by conducting suitable tests.
• Draw the equivalent circuit of transformer and predetermine the efficiency and regulation.
• Describe the working principle of auto transformer, three phase transformer with different types
of connections.

CONTENT BEYOND THE SYLLABUS
1. Construction, working and application of universal motor.
2. Transformer modelling using ETAP software.
INTERNAL ASSESSMENT DETAILS
Assessment No. CAT-I CAT-II MODEL
Topic Nos. 1-18 19-33 1-33
Date
ASSIGNMENT DETAILS
Class / Strength: II EEE/ 31
ASSIGNMENT: I (40 Marks) (Before CAT – I)
Topics for Reference (1-18)
Question / Activity / Activities
LEVEL-1(10 Students)
Level-I Question /Activities Evaluation
L1-
Q1-Q4
Poster Presentation
1. Indian Standard Specifications (ISS)
2. Energy balance in magnetic circuits
3. Design of armature winding
4. load characteristics of different types of DC generators
Poster Design: 10 Marks
Presentation: 25 Marks
Q&A: 05 Marks
L1-
Q5-Q7
Quiz
1. DC generators
2. DC Motors
3. Singly excited and multi excited magnetic field system
Totally 20 questions.
(20*2= 40 Marks)
L1-
Q8-Q10
Think Break exercise on
1. Statically and dynamically induced EMF
2. Principle of operation of DC generator & DC motor
3. Starting methods of DC motors
Minimum 5 problems to be
solved on the specific topic.
Formula: 5 Marks
Content: 30 Marks
Clarity: 05 Marks
L2-
Q11-Q14
Mind Mapping
1. Statically induced EMF
2. Parallel operation of DC Generators
3. Armature reaction
4. Armature windings and its types
Concept clarity: 05 Marks
Model: 25 Marks
Assignment No. I II
Topic Nos. for reference 1-18 19-33
Deadline

L2-
Q15-Q17
Power Point Presentation
1.Energy balance in magnetic circuits
2.Introduction to Indian Standard Specifications
3.Wave shape of induced emf
PPT: 15 Marks
Report: 10 Marks
Q&A: 05 Marks
L2-
Q18-Q20
Seminar
1. Co-energy in singly excited magnetic field system
2. Constructional details of DC generator
3. speed control of DC motors
Communication: 05 Marks
Report: 15 Marks
Q&A: 05 Marks
LEVEL-3 (11 Students)
L3-
Q21-Q26
APH
1. Dynamically induced EMF
2. Torque equations and power developed by armature
3. Parallel operation of DC Generators
4. ISS- Role and significance in testing
5. Demagnetizing and cross magnetizing
6. Armature windings and its types
Report: 15 Marks
Q&A: 05 Marks
L3-
Q27-31
GATE Questionaire
1. Fundamentals of Magnetic circuits
2. Co-energy in singly excited and multi excited magnetic
field system
3. Magnetic fields in rotating machines
4. Constructional details of DC generator
5. EMF equation of DC generator
Reasoning level questions 20
With necessary explanation.
(20*2=40 Marks)
Class / Strenth: II EEE/ 31
ASSIGNMENT: II (40 Marks) (Before CAT –II)
Topics for Reference (19- 33)
Question / Activity / Activities
Level-I Question /Activities EVALUATION
L1-
Q1-Q4
Poster Presentation
1. Testing of DC Machines
2. Parallel operation of single-phase transformers
3. Three Phase Transformer connection
4. Applications of DC motors.
Poster Design: 10 Marks
Q&A: 05 Marks.
L1-
Q5-Q7
Quiz
1.Losses and efficiency in DC machine
2. Voltage regulation of single phase transformer
3. Condition for maximum efficiency in DC motors
Total 20 Questions
(20x2 = 40 Marks)
L1-
Q8-Q10
Think Break exercise on
1. Separation of core losses in DC motors
2. Construction of auto transformer
3. Equivalent circuit of single phase transformer
Minimum 5 problems to be
solved on the specific topic.
Formula: 5 Marks
Content: 30 Marks
Clarity: 05 Marks

L2-
Q11-Q14
Mind Mapping
1. Open circuit and short circuit test on transformer
2. Efficiency in DC machine
3. Hopkinson's test on transformer
4. All day efficiency in single phase transformer
Concept clarity: 05 Marks
Model: 25 Marks
L2-
Q15-Q17
Power Point Presentation
1. Construction and working of auto transformer
2. Applications of DC motors.
3. Polarity test on single phase transformer
PPT: 15 Marks
Report: 10 Marks
Q&A: 05 Marks.
L2-
Q18-Q20
Seminar
1. Operating principle of single phase transformer
2. Phasor diagrams of single-phase transformer
3. Applications of scott connection
Report: 15 Marks
Q&A: 05 Marks
L3-
Q21-Q26
GATE Questionaire
1. Voltage regulation of single-phase transformer
2. Losses and efficiency in DC machine
3. Three phase transformer connection
4. Testing of DC Machines
6. Construction and working of auto transformer
Reasoning level questions
20 With necessary
explanation.
(20*2=40 Marks)
L3-
Q27-31
APH
1. Equivalent circuit of single phase transformer
2. Applications of Scott connection
3. Swinburne’s test on DC motors
4. Losses and efficiency in DC machine,
Communication: 05
Marks
Report: 15 Marks
Q&A: 05 Marks
COURSE ASSESSMENT PLAN
CO CO Description Weightage CAT1 CAT2 Model Assign.-1 PCE AU
CO1 Apply the laws governing the
electromechanical energy
conversion for singly and
multiple excited systems.
20% ✓ ✓ ✓
CO2 Explain the construction and
working principle of DC
machines.
10% ✓ ✓ ✓
CO3 Interpret various
characteristics of DC
machines.
10% ✓ ✓ ✓ ✓ ✓
CO4 Compute various performance
parameters of the machine, by
conducting suitable tests.
20% ✓ ✓ ✓ ✓ ✓
CO5 Draw the equivalent circuit of
transformer and predetermine
the efficiency and regulation.
20% ✓ ✓ ✓
CO6 Describe the working
principle of auto transformer,
three phase transformer with
different types of connections.
20% ✓ ✓ ✓

COURSE OUTCOME ALLIGNMENT MATRIX – MODEL EXAM SAMPLE QUESTION SET
Q.No Question Marks CO BTL PI
1. Define magnetic flux density. 2 CO1 L1 1.2.1
2. A coil of 1500 turns carrying a current of 5 Amps produces
a flux of 2.5 mWB. Find the self inductance of the coil.
2 CO1 L2 1.1.2
3. Give the function of armature in the D.C generator. 2 CO2 L1 2.1.3
4. Distinguish between lap and wave winding used in a D.C.
generator.
2 CO2 L2 2.3.2
5. Why do you need a starter for a DC motor? 2 CO3 L2 2.2.4
6. Draw speed -torque characteristics of DC series motor. 2 CO3 L1 5.1.1
7. What is the condition for maximum efficiency of
transformer?
2 CO5 L1 1.3.1
8. Why transformer rating is expressed in kVA? 2 CO5 L2 2.2.4
9. Draw Scott connection of a transformer 2 CO6 L1 1.4.1
10. State the advantages and applications of auto-transformer. 2 CO6 L2 2.1.2
11.a.(i) Derive an expression for an energy density in magnetic
circuits.
(07) CO1 L4 3.3.1
11.a.(ii) Draw the circuit and explain the concept of a doubly excited
magnetic system.
(06) CO1 L3 1.1.2
11.b.(i) Obtain the expression for field energy and mechanical force. (07) CO1 L3 1.2.1
11.b.(ii) Explain about the magnetic field in rotating machines. (06) CO1 L2 1.4.1
12.a. Two 500 V DC shunt generator rated at 100 kW and 200 kW
respectively are operating in parallel. Both of them have
linearly drooping external characteristics. Voltage
regulation of the first generator is 6%. Determine the
common bus voltage and current shared by each of the
generator when their parallel combination is to supply a
current of 300A.
(13) CO3 L2 2.1.3
12.b Explain the construction and operation of DC generator. (13) CO2 L3 3.1.6
13.a.(i) Explain the various methods of speed control for DC shunt
motor.
(07) CO3 L3 3.2.2
13.a.(ii) Derive in detail the condition for maximum efficiency of DC
Machine.
(06) CO4 L4 2.4.1
13.b.(i) Draw and explain the characteristics of DC shunt motor. (07) CO3 L2 3.3.1
13.b.(ii) What are the various methods of braking of dc motor?
Explain in detail.
(06) CO4 L2 2.1.3
14.a Explain the principle of operation of a transformer. Derive
its EMF equation.
(07) CO5 L1 1.3.1
14.b A 11000/230 V, 150 kVA, 1-phase, 50Hz transformer has
core loss of 1.4 kW and F.L. copper loss of 1.6 kW.
Determine (i) The kVA load for maximum efficiency at
unity p.f. (ii) The efficiency at 0.8 pf leading.
(07) CO5 L4 2.4.2
15.a Calculate the efficiency for half, full load of a 100-kVA
transformer for the P.F of unity and 0.8 the copper loss at
full load is 1000 W and iron loss is 1000 W.
(13) CO5 L4 3.2.3
15.b A 3-phase step down transformer is connected to 6.6 𝑘𝑉
mains and takes 10A. Calculate the secondary line voltage
and line current for the (i) ∆/∆ (ii) 𝑌/𝑌 (iii) ∆/𝑌 and (iv)
𝑌/∆ connections. The ratio of turns per phase is 12 and
neglects no load losses.
(13) CO6 L4 2.4.2

16.a A 3-phase, 500kVA, 6000V/400V, 50Hz, delta-star
connected transformer is delivering 300kW, at 0.8 pf
lagging to a balanced 3-phase load connected to the LV side
with HV side supplied from 6000 V. 3-phase supply.
Calculate the line and winding currents in both the sides.
Assume the transformer to be ideal.
(07) CO6 L5 3.1.6
16.(b) A 4-pole lap wound shunt generator supplies 60 lamps of
100W, 240V each; the field and armature resistance are
55Ω and 0.18Ω respectively. If the brush drop is 1Vfor each
brush finds (i) Armature current (ii) current per path (iii)
Generated emf (iv) Power output of DC machine.
(15) CO3 L6 4.1.1
ASSESSMENT PAPER QUALITY MATRIX
PART BTL1 BTL2 BTL3 BTL4 BTL5 BTL6
A 1,3,6,7,9 2,4,5,8,10 - - - -
B 14. a
11.b.ii,13.b.i,
13.b.ii,12.a
11.a.ii, 11.b. i,
12.b, 13.a. i,
11.a.i,
13.a.ii, 14.b, 15.a 15.b -
C - - - - 16.a 16.b
TOTAL 13% 24% 18% 21% 16% 8.3%
Distribution 37% 39% 24%
Prepared by Verified By
Dr.P.Narasimman HOD/ EEE
Approved by
PRINCIPAL

EE3303-EM-I-CP.pdf

Recommended

Recommended

More Related Content

Similar to EE3303-EM-I-CP.pdf

Similar to EE3303-EM-I-CP.pdf (20)

Recently uploaded

Recently uploaded (20)

EE3303-EM-I-CP.pdf