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APJ ABDUL KALAM TECHNOLOGICAL UNIVERSITY
FIFTH SEMESTER B.TECH DEGREE EXAMINATION, DECEMBER 2018

Course Code: EC307
Course Name: POWER ELECTRONICS & INSTRUMENTATION

Max. Marks: 100 Duration: 3 Hours
PART A
Answer any two full questions, each carries 15 marks. Mar
ks

a) Compare power MOSFETs and power BJTs. (5) ४) With neat sketch explain the static
and dynamic characteristics of power diodes. (10)
a) Draw the circuit of a Buck converter and explain its working with relevant (6) waveforms.
b) What are the advantages of isolated converter circuits over the basic converter (9)
circuits? Explain the forward converter circuit with relevant waveforms.
a) Draw the structure of an IGBT and explain its operation. (8) b) Explain the operation

of a Flyback converter. (7)

PART 8
Answer any two full questions, each carries 15 marks.
a) With relevant waveforms explain the circuit of a push pull single phase inverter ) 9)
circuit.
b) Explain the principle of space vector modulation in three phase inverter circuits. (
6)
a) Draw the block diagram and explain the functional elements of an instrument? (5)

b) What do you mean by static characteristics of an instrument? Define any six static (10)
parameters of an instrument.

a) Explain the principle of operation of switched mode inverters. Draw the circuit of (8) a full

bridge single phase inverter circuit and explain its operation with relevant waveforms for R load.

b) Draw a Maxwell’s bridge circuit and derive the condition for balance of the bridge (7)
for finding the unknown inductance value.
PARTC
Answer any two full questions, each carries 20 marks.
a) Mention a few criterion that has to be considered in the selection of transducer for (5)
a particular application.

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