1. Three Phase Supply
a) Advantages of 3 phase system over single phase system
b) Star delta connections
c) Relation between phase voltage and line voltage, phase current and line
current in a 3 phase system
d) Power and power factor(p.f.) in 3 phase system and their measurements,
importance of p.f. (simple problems)
(06 hrs)
2. Transformer
Principle of transformer, construction, voltage and current transformation.
Methods of connection in 3 phase transformers, current and voltage relationship,
auto transformer and its uses, instrument transformer, voltage regulation and its
significance, need for isolation, electrical and transients suppression, principles
of isolation transformer, specifications of all types of transformers. Losses in a
transformer
(08 hrs)former
3. DC Motor
Principle, significance of back emf, types of motors and their construction, motor
characteristics for shunt and series, speed control of DC motors and factors
controlling the speed. Starting methods, construction and working of 3 point
starter, applications (simple problems)
(08 hrs)
4. Three Phase Induction Motors
Principle, construction, concept of slip, torque and characteristics, effect of motor
resistance on torque (running and starting), rotor current, output power, different
(08 hrs)
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methods of speed control. Starting methods and constructional and working of
3 point starter, applications (simple problems)
5. Synchronous Motors
Principle, construction and working, effect of load and excitation on synchronous
motor. Starting of motor and their applications
(06 hrs)
6. Single Phase Motors
Principle, construction, working speed, control, starting and applications of the
following motors:
a) Induction motor
c) Universal motor
(06 hrs)
7. Stepper Motor and Servo Motor
Types, construction, working and their applications