Electric Machines II
Course Objectives:
To impart knowledge on constructional details, operating principle and performance of 3phase Synchronous Machines and Fractional Kilowatt Motors.
 Three Phase Synchronous Generator(8 hours)
 Constructional Details, Armature Windings, Types of Rotor, Exciter
 Working Principle, Rotating Magnetic Field
 EMF equation, distribution factor, pitch factor
 Armature Reaction and its effects
 Alternator with load and its phasor diagram
 Voltage Regulations
 Parallel Operation and Synchronization
 Operation on infinite bus
 Three Phase Synchronous Motor(7 hours)
 Principle of operation
 Starting methods
 No load and Load operation, Phasor Diagram
 Effect of Excitation and power factor control, V and Inverted V Curves
 Hunting
 Power angle Characteristics of Cylindrical Rotor Machine
 Two reaction Model of Salient pole machine
 Power Angle Characteristics of Salient Pole Machine
 Fractional Kilowatt Motors(12 hours)
 Single phase Induction Motors: Construction and Characteristics
 Double Field Revolving Theory
 Split phase Induction Motor
 Capacitor start motor
 Capacitors start and run motor
 Shaded pole motor
 Reluctance start motor
 Single phase Synchronous Motor
 Reluctance motor
 Hysteresis motor
 Universal motors
 Special Purpose Machines: Stepper motor, Schrage motor and Servo motor
Practical:
 To study Noload characteristics of a 3phase synchronous generator
 To study load characteristics of synchronous generator with (a) resistive load (b) inductive load and (c) capacitive load
 To study the effect of excitation on performance of a synchronous motor and to plot V curve
 To study the effect of a capacitor on the starting and running of a singlephaseinduction motor
 To study the operating characteristics of universal motors
References:
 I.J. Nagrath&D.P.Kothari,” Electrical Machines”, Tata McGraw Hill
 S. K. Bhattacharya, “Electrical Machines”, Tata McGraw Hill
 Husain Ashfaq ,” Electrical Machines”, DhanpatRai& Sons
 A.E. Fitzgerald, C.KingsleyJr and Stephen D. Umans,”Electric Machinery”, Tata McGraw Hill
 P. S. Bhimbra, “Electrical Machines”’ Khanna Publishers
 Irving L.Kosow, “Electric Machine and Tranformers”, Prentice Hall of India.
 M.G. Say, “The Performance and Design of AC machines”, Pit man & Sons.
 Bhag S. Guru and Huseyin R. Hizirogulu, “Electric Machinery and Transformers” OxfordUniversity Press, 2001.
Evaluation Scheme
The questions will cover all the chapters of the syllabus. The evaluation scheme will be as indicates in the table below.
Chapter 
Hours 
Marks Distribution* 
1 
8 
14 
2 
7 
12 
3 
12 
14 
Total 
27 
40 
*Note: There may be a minor deviation in the marks distribution.
