Download GTU (Gujarat Technological University Ahmedabad) B.Tech/BE (Bachelor of Technology/ Bachelor of Engineering) 2020 Winter 6th Sem 2161708 Power Electronics Previous Question Paper
Enrolment No.___________
GUJARAT TECHNOLOGICAL UNIVERSITY
BE- SEMESTER?VI (NEW) EXAMINATION ? WINTER 2020
Subject Code:2161708 Date:22/01/2021
Subject Name:Power Electronics
Time:02:00 PM TO 04:00 PM Total Marks: 56
Instructions:
1. Attempt any FOUR questions out of EIGHT questions.
2. Make suitable assumptions wherever necessary.
3. Figures to the right indicate full marks.
Q.1 (a) Define:
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1) Duty cycle
2) Revers recovery time for diode
3) Hold time of filter-rectiffier.
(b) Write a short note on the following terms associated with SCR:
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1) Holding current
2) Latching current
(c) Write a short note on IGBT in detail.
07
Q.2 (a) Give comparison between single-phase and three-phase rectifier.
03
(b) Short note : applications of IGBT and MOSFET
04
(c) With waveforms explain single-phase half-wave controlled rectifier
07
with resistive load.
Q.3 (a) What is inverter? Give the difference between oscillators and
03
inverter.
(b) Short note: Quasi square wave inverter.
04
(c) Explain two-level chopper and two-level inverter using single pole 07
double throw switch.
Q.4 (a) Write a short note on isolated converter.
03
(b) Short note: Switching characteristics of transistor.
04
(c) Write a short note on power MOSFET.
07
Q.5 (a) Explain the benefits of isolation between input and output.
03
(b) Short note: Opto-isolated MOSFET drive circuit.
04
(c) Write a short note on the operation of step-down converter with
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waveforms of the various signals of circuit.
Q.6 (a) Short note : DIAC
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(b) Explain in detail the importance of freewheeling DIODE
04
(c) Draw & explain the V-I characteristics of TRIAC.
07
Q.7 (a) Short note: Single phase two level inverter topology.
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(b) Short note: Chopper
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(c) Explain in detail the Snubber circuit.
07
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Q.8 (a) Give the classification of diode based on the turn-off time.
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(b) Short note: buck-boost converter.
04
(c) Write a short note on six step inverter.
07
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This post was last modified on 04 March 2021