Lesson Plan
Department:
EEE
Branch & Semester:
B.E & EEE
Course code & Title:
22EE303 & Electrical Machines I
Unit Title:
Induction Motor
CO / Lesson No (GO):
4/1
1. Prerequisite(s): Electromagnetic material, Mutual Inductance, Three phase AC system
2. Topic: Three phase Induction motor - Construction - Types of rotor - Operation
3. General Objective (GO): To understand the construction and working of three phase
induction motor
4. Specific Objectives (SO):
 SO1 – Infer the production of rotating field in a three phase induction
motor by applying three phase ac supply (U/C)
 SO2 - Illustrate with a neat diagram about the constructional details of
three phase induction motor. (U/C)
 SO3 – Compare the two types of rotor used in induction motor and its
operation.(An/C)
5. Mapping Table:
SO
PO
PO/PSO Competency
PO/PSO Indicator
SO1
1,2,4/ 14
1.1,1.2,1.3,1.4,2.1,2.2,
1.1.1,1.2.1,1.3.1,1.4.1,2.1.1,2.1.2,2.1.3.
SO2
1,2,4/ 14
1.1,1.2,1.3,1.4,2.1/14.2
1.1.1,1.2.1,1.3.1,1.4.1,2.1.1,2.1.2,4.3.2/14.2.2.
SO3
1,2,4/ 14
1.1,1.2,1.3,1.4,2.1 /14.2
1.1.1,1.2.1,1.3.1,1.4.1,2.1.1,2.1.2,2.1.3,
3.2/14.2.2.
6. Mind map and Summary:
Summary:






Very simple & extremely rugged
Cost is low very & reliable
In normal running condition, no brushes are needed
Requires minimum maintenance
Speed decreases with increase with increase in load
Starting torque is somewhat inferior to d.c shunt motor
 Made up of this laminations of silicon steel to reduce hysteresis & eddy current Loss
 Squirrel cage rotor- Rotor bars are permanently short-circuited on themselves
 (ii) Phase -wound or wound rotor

Rotor is wound for 3 phase

Slip rings are mounted on the shaft with brushes

Brushes are externally connected to a 3 phase star connected armature
7. Reference:
[1] M.G.Say, Performance and Design of Alternating Current Machines, 3rd Edition, CBS Publisher,
2017.
[2] D. P. Kothari and I. J. Nagrath, Electric Machines, Tata McGraw Hill Publishing
Company Ltd, FourthEdition 2018.
[3] Stephen J.Chapman, Electric Machinery Fundamentals, Tata McGraw Hill, New Delhi, 2018.
[4] E. Fitzgerald, Charles Kingsley, Stephen.D.Umans, Electric Machinery, Tata McGraw
Hill publishingCompany Ltd, New Delhi ,2015.
Prepared by
[Mr. A. Nandhakumar]
Lesson Plan
Department:
EEE
Branch & Semester:
B.E & EEE
Course code & Title:
22EE303 & Electrical Machines I
Unit Title:
Induction Motor
CO / Lesson No (GO):
4/2
1. Prerequisite(s): Torque, Horse Power, Relationship between speed and torque, Slip
2. Topic: Torque equation and Torque - slip characteristics
3. General Objective (GO): Students will be able to understand the torque equation of
induction motor and develop the torque speed characteristics
4. Specific Objectives (SO):
 SO1 – Formulate an expression for torque equation of three phase induction
motor. (U/C)

SO2 – Indicate the condition for maximum torque in a 3-phase induction
motor (U/C)
 SO3 – Differentiate the characteristics of squirrel cage and slip ring induction
motor.(An/C)
5. Mapping Table:
SO
PO
PO/PSO Competency
PO/PSO Indicator
SO1
1,2,13
1.1,1.2,2.1,13.1
1.1.1,1.2.1,2.1.1,13.1.2
1,2,13
1.2,2.3,13.1
1.2.1,2.3.1,13.1.2
1,2,13
1.1,1.2,2.4,13.1
1.1.1,1.2.1,2.4.1,2.4.3,13.1.2
SO2
SO3
6. Mind map and Summary:
T= 3/ws ×SE22
R2/R22 +SX22
Tst =3/2πns×
E22R2/R22+X22
TORQU
E
EQUATI
ON
Starting
torque
Condition for
maximum torque
SX2=R2
Tm=
kE22/2X2
T F.L/Tm=
2SfSm/Sm2+Sf2
Sf= Full load slip
Summary:
 Torque Equation T α SE22 (R2/R22 +SX22)
N-m
N-m
 Starting torque Tst = (3/2πns)×
 Condition for maximum torque SX2=R2
 Tm = kE22/2X2
 Range S = 0 to S = Sm ---------- Low slip region ---------- Range S = Sm to S = 1 -------- High slip region ------------ T F.L/Tm = 2SfSm/Sm +Sf
E2 R2/R2 +X22
2
2
Stable operation
Unstable operation
7. Reference:
[1] M.G.Say, Performance and Design of Alternating Current Machines, 3rd Edition, CBS Publisher,
2017.
[2] D. P. Kothari and I. J. Nagrath, Electric Machines, Tata McGraw Hill Publishing
Company Ltd, FourthEdition 2018.
[3] Stephen J.Chapman, Electric Machinery Fundamentals, Tata McGraw Hill, New Delhi, 2018.
[4] E. Fitzgerald, Charles Kingsley, Stephen.D.Umans, Electric Machinery, Tata McGraw
Hill publishingCompany Ltd, New Delhi ,2015.
Prepared by
[Mr. A. Nandhakumar]
Lesson Plan
Department:
EEE
Branch & Semester:
B.E & EEE
Course code & Title:
22EE303 & Electrical Machines I
Unit Title:
DC Machines
CO / Lesson No (GO):
4/3
1. Prerequisite(s): Power loss, slip, constant loss, variable loss
2. Topic:
Equivalent circuit model
3. General Objective (GO): The student will be able to develop an equivalent circuit for
induction motor
4. Specific Objectives (SO):
 SO1 – Classify the losses in three phase induction motor. (U/C)
 SO2 – Identify the losses computed in open circuit and blocked rotor test. (U/C)
 SO3 – Develop an equivalent circuit from the parameters obtained in the no load
and blocked rotor test. (U/C)
5. Mapping Table:
SO
PO
PO/PSO Competency
PO/PSO Indicator
SO1
1,2,14
1.1,1.2,2.1,14.1
1.1.1,1.2.1,2.1.1,14.1.2
SO2
1,2,13
1.2,2.3,13.1
1.2.1,2.3.1,13.1.2
1,2,13
1.1,1.2,2.4,13.1
1.1.1,1.2.1,2.4.1,2.4.3,13.1.2
SO3
6. Mind map and Summary:
Summary:





7. Reference:
Magnetizing component of core X0 = V1/Im
Resistance R0 = V1/Ic
Variable rotor resistance R2 = R2+ R2(1-s)/s
Gross mechanical power developed Pg = 3 I2’2 Rl’
Pg is maxmimum when Rl’ = standstill impedance of the motor
[1] M.G.Say, Performance and Design of Alternating Current Machines, 3rd Edition, CBS Publisher,
2017.
[2] D. P. Kothari and I. J. Nagrath, Electric Machines, Tata McGraw Hill Publishing
Company Ltd, FourthEdition 2018.
[3] Stephen J.Chapman, Electric Machinery Fundamentals, Tata McGraw Hill, New Delhi, 2018.
[4] E. Fitzgerald, Charles Kingsley, Stephen.D.Umans, Electric Machinery, Tata McGraw
Hill publishingCompany Ltd, New Delhi ,2015.
Prepared by
[Mr. A. Nandhakumar]
Lesson Plan
Department:
EEE
Branch & Semester:
B.E & EEE
Course code & Title:
22EE303 & Electrical Machines I
Unit Title:
Induction Motor
CO / Lesson No (GO):
4/4
1. Prerequisite(s): Magnetic fields, DC machine, Armature windings, Field system
2. Topic: Double field revolving theory.
3. General Objective (GO): To understand the principle of double field revolving theory
and construction of single phase induction motor.
4. Specific Objectives (SO):
 SO1 – Infer the concept of double field revolving theory. (U/C)
 SO2 – Illustrate the construction of single phase induction motor. (U/C)
 SO3 – Compare the single phase and three phase motor based on its operating
principle. (U/C)
5. Mapping Table:
SO
PO
SO1
1,2/ 14
1.2,1.3,1.4,2.1,2.2,2.4/14.2
1.2.1,1.3.1,1.4.1,2.1.3,2.1.1,2.2.2,2.4.4/14.1.1,14.2.2
SO2
1,2/ 14
1.2,1.3,1.4,2.2,2.4/14.2
1.2.1,1.3.1,1.4.1,2.1.3,2.2.2,2.4.4/14.1.1,14.2.2
1,2/ 14
1.2,1.3,1.4,2.1,2.2,2.4/14.2
1.2.1,1.3.1,1.4.1,2.1.3,2.1.1,2.2.2,2.4.4/14.1.1,14.2.2
SO3
PO/PSO Competency
PO/PSO Indicator
6. Mind map and Summary:
Summary:

Both the stator and rotor components rotates in opposite direction.

The resultant flux is zero and that is the instantaneous value of stator flux at
the time of start.

The net torque experienced by the rotor is zero.

Induction motor is not a self-starting motor.
7. Reference:
[1] M.G.Say, Performance and Design of Alternating Current Machines, 3rd Edition, CBS Publisher,
2017.
[2] D. P. Kothari and I. J. Nagrath, Electric Machines, Tata McGraw Hill Publishing
Company Ltd, FourthEdition 2018.
[3] Stephen J.Chapman, Electric Machinery Fundamentals, Tata McGraw Hill, New Delhi, 2018.
[4] E. Fitzgerald, Charles Kingsley, Stephen.D.Umans, Electric Machinery, Tata McGraw
Hill publishingCompany Ltd, New Delhi ,2015.
Prepared by
[Mr. A. Nandhakumar]
Lesson Plan
Department:
EEE
Branch & Semester:
B.E & EEE
Course code & Title:
22EE303 & Electrical Machines I
Unit Title:
Induction motor
CO / Lesson No (GO):
4/5
1. Prerequisite(s): Magnetic fields, self-starting, cross field, double field
2. Topic: Methods of starting induction motor.
3. General Objective (GO): To understand the working and characteristics of split phase,
capacitor start and capacitor run single phase induction motor.
4. Specific Objectives (SO):
 SO1 – Interpret the functions auxiliary and starting winding in a single phase induction
motor. (U/C)
 SO2 – Illustrate the operation of split phase motor. (U/C)
 SO3 – Compare the performance of a capacitor start and capacitor run induction motor.
(An/C)
5. Mapping Table:
SO
PO
SO1
1,2/ 14
1.2,1.3,1.4,2.1,2.2,2.4/14.2
1.2.1,1.3.1,1.4.1,2.1.3,2.1.1,2.2.2,2.4.4/14.1.1,14.2.2
SO2
1,2/ 14
1.2,1.3,1.4,2.2,2.4/14.2
1.2.1,1.3.1,1.4.1,2.1.3,2.2.2,2.4.4/14.1.1,14.2.2
1,2/ 14
1.2,1.3,1.4,2.1,2.2,2.4/14.2
1.2.1,1.3.1,1.4.1,2.1.3,2.1.1,2.2.2,2.4.4/14.1.1,14.2.2
SO3
PO/PSO Competency
PO/PSO Indicator
6. Mind map and Summary:
Summary:



Split phase motor carries a series resistance in auxiliary winding
Capacitor start improves the starting torque
Capacitor start capacitor run improves the power factor.
7. Reference:
[1] M.G.Say, Performance and Design of Alternating Current Machines, 3rd Edition, CBS Publisher,
2017.
[2] D. P. Kothari and I. J. Nagrath, Electric Machines, Tata McGraw Hill Publishing
Company Ltd, FourthEdition 2018.
[3] Stephen J.Chapman, Electric Machinery Fundamentals, Tata McGraw Hill, New Delhi, 2018.
[4] E. Fitzgerald, Charles Kingsley, Stephen.D.Umans, Electric Machinery, Tata McGraw
Hill publishingCompany Ltd, New Delhi ,2015.
Prepared by
[Mr. A. Nandhakumar]