UNIT-I
1. Explain the methods of
analyzing the magnetic circuits
2. Explain the two types of
magnetic circuits with neat diagram
3. Explain in detail about
electromagnetic induction
4. Draw the typical B-H curve and
hysteresis loop and explain its concepts
5. Explain the meaning of self
induced emf, mutually induced emf, statically induced emf, dynamically induced emf and give
practical examples
6. Distuingusih between
statically induced emf and dynamically induced emf
7. Prove that M=k√L1L2
8. Explain about magnetization
curve for Ferro magnetic material
9. Explain in detail about
hysteresis loss and eddy current loss in detail
10. Explain various types’ core
loss on detail
UNIT-II
1. Explain the construction of a
transformer.
2. a. Derive the emf equation of
a transformer.(8)
b. Develop an approximate
equivalent circuit for a two winding transformer. (8)
3. A 100 KVA 1100/200v single
phase transformer has the following parameters.R1 = 1Ω,
X1= 3Ω , R2=0.04Ω, X2=0.012Ω .
Find the equivalent resistance and leakage reactance as referred to High
Voltage winding.
4. a. Discuss about the working
principle of a transformer. (8)
b. Draw the phasor diagram &
explain the operation of a practical transformer on load. (8)
5. Draw the equivalent circuit of
a single phase 1100/220 V transformer on which the Following results were
obtained.
i . 1100V, 0.5A, 55W on primary,
secondary being open circuited. (8)
ii. 10v, 80A, 400W on low voltage
side, high voltage being short circuited. (8)
Calculate the voltage regulation
and efficiency of the above transformer when secondary supply is 100A at 0.8 pf
lagging.