EX-502 RGPV B.Tech
Power Electronics (PE)
Previous year papers and the official syllabus are free to read, no account needed.
Previous Year Papers
5 papers, latest Dec 2025
- EX-502 paper, Dec 2025
- EX-502 paper, Jun 2025
- EX-502 paper, Dec 2024
- EX-502 paper, May 2024
- EX-502 paper, Nov 2023
Syllabus, notes and important questions for EX-502
Syllabus units
Topics as the official RGPV syllabus lists them.
Unit 1 Advantages and application of power electronic devices; Power diode, power transistor, GTO, Triac, Diac, Power MOSFET, IGBT, LASCR, Fast recovery diode, Schottky diode, MCTs; SCR operation, characteristics and commutation techniques 27 topics
- Advantages and applications of power electronic devices
- Characteristics, symbols and applications of power diodes
- Characteristics, symbols and applications of power transistors
- Characteristics, symbols and applications of GTOs
- Characteristics, symbols and applications of Triacs
- Characteristics, symbols and applications of Diacs
- Characteristics, symbols and applications of Power MOSFETs
- Characteristics, symbols and applications of IGBTs
- Characteristics, symbols and applications of LASCRs
- Characteristics, symbols and applications of fast‑recovery diodes
- Characteristics, symbols and applications of Schottky diodes
- Characteristics, symbols and applications of MCTs
- Principle of operation of SCRs
- Two‑transistor analogy for SCRs
- Construction features of SCRs
- Static characteristics of SCRs
- Turn‑on and turn‑off conditions of SCRs
- Gate characteristics of SCRs
- Methods for turning on SCRs
- Turn‑off methods for SCRs
- Commutation techniques (Class A, B, C, D, E, F)
- Firing of SCRs in three‑phase circuits
- Resistance firing circuit and RC firing circuit
- UJT firing circuit and ramp triggering
- Design of snubber circuits and gate protection
- SCR rating, over‑voltage and over‑current protection
- Series and parallel operation of SCRs, string efficiency and associated problems
Unit 2 Operation and analysis of rectifier circuits 12 topics
- Single‑phase half‑wave uncontrolled rectifier with resistive load
- Single‑phase full‑wave uncontrolled rectifier with resistive load
- Three‑phase uncontrolled rectifier with resistive load
- Single‑phase half‑wave controlled rectifier with resistive load
- Single‑phase full‑wave controlled rectifier with resistive load
- Three‑phase controlled rectifier with resistive load
- Operation with resistive‑inductive (R‑L‑E) loads – continuous and discontinuous conduction
- Effect of freewheeling diode on rectifier performance
- Influence of source inductance on rectifier characteristics
- Estimation of average load voltage and load current for each configuration
- Active and reactive power input calculations for each rectifier type
- Comparison between midpoint and bridge rectifier circuits
Unit 3 Inverter topologies and control 10 topics
- Series and parallel inverter configurations
- Voltage‑source and current‑source inverter principles
- Single‑phase bridge inverter
- Three‑phase bridge inverter
- Self‑commutated inverters
- McMurray and MC‑Murray‑Beddford inverter topologies
- Voltage control techniques for single‑phase bridge inverter
- Voltage control techniques for three‑phase bridge inverter
- Harmonic generation in inverters
- Harmonic reduction techniques
Unit 4 Chopper circuits and control strategies 10 topics
- Principle of operation of choppers
- Various control strategies for choppers
- Step‑up (boost) chopper configuration
- Step‑down (buck) chopper configuration
- Step‑up/step‑down (buck‑boost) chopper configuration
- Chopper types A, B, C, D, and E
- Steady‑state analysis of chopper circuits
- Current commutation in chopper circuits
- Voltage commutation in chopper circuits
- Jones & Morgen’s chopper analysis
Unit 5 Cycloconverters, AC voltage controllers and SMVRs 8 topics
- Single‑phase midpoint and bridge cycloconverter configurations
- Three‑phase cycloconverter configuration and operation principles
- AC voltage controllers using SCRs and TRIACs for single‑phase full‑wave control with R and RL loads
- Estimation of RMS load voltage and RMS load current for AC voltage controllers
- Input power factor calculation for AC voltage controllers
- Three‑phase AC voltage controller (conceptual analysis)
- Dual converter operation
- Switched‑mode voltage regulators: buck, boost, buck‑boost, and C‑k regulators
Exam insights
Counted from 5 past EX-502 papers.
Marks asked per paper, by unit
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Unit 1 Power Electronic Devices and SCR Characteristics 27 marks
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Unit 2 Phase Controlled Rectifiers 20 marks
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Unit 3 Inverters 21 marks
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Unit 4 Choppers 20 marks
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Unit 5 Cycloconverters and AC Voltage Controllers 25 marks
Average marks of the questions from each unit in one paper. You answer only some of them, so the total is more than the paper’s maximum.
Asked again and again
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Explain the working principle of a single-phase bridge-type step-down cycloconverter with circuit diagram and input-output waveforms (e.g., output frequency $f/2$ for resistive load).
Asked 4 times: 2025, 2024, 2019
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Explain the working of a single-phase fully controlled / full-wave bridge controlled rectifier with waveforms for R / RL load
Asked 4 times: 2025, 2023, 2020
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Explain the working / operation of a single-phase fully controlled (full-wave bridge) converter with RL load, circuit diagram and waveforms including load voltage and SCR voltage.
Asked 4 times: 2025, 2023, 2020