15

16

20

a)
b)

a)

b)

a)
b)

b)

a)
b)

F7155

Calculate the line currents in each phase.
With the help of a neat diagram, explain the working of a nuclear power plant.

Explain the need for high voltage transmission.
Explain the principle and operation of circuit breaker used in substation.

MODULE 5

Answer any one full question
Explain different types of 60 generators with suitable circuit diagrams and obtain
voltage and current expressions of each.
The maximum value of flux density in the core of a 250/3000V, 50Hz single
phase transformer is 1.5Wb/m2. If the emf /turn 15 8V, determine 1) primary and
secondary number of turns ii) area of the core.
OR

Draw and explain the constructional details of 3 phase transformers.
A 220V DC shunt motor takes 30A at full load. Find the back emf developed if
the armature and shunt field resistances are 0.5Q and 110Q respectively.

MODULE 6

Answer any one full question
Draw and explain the constructional details of a 3 phase squirrel cage induction
motor.
A 6 pole 3phase induction motor operates from a supply whose frequency is
50Hz. Calculate
i) The speed at which the magnetic field of the stator is rotating.
ii) The speed of the rotor when the slip is 0.03
OR

Explain why single phase induction motors are not self-starting.

Draw and explain the constructional features of a three phase induction motor.
%%%%

Page 2 of 2

(10)
(5)
(5)
(7)

(3)

(5)
(5)

(5)

(5)

(5)
(5)