Some common power devices are the power diode, thyristor, power MOSFET, and IGBT. The power diode and power MOSFET operate on similar principles to their low-power counterparts, but are able to carry a larger amount of current and are typically able to support a larger reverse-bias voltage in the off-state. Structural changes are often made in a power device in order to accommodate the higher current density, higher power dissipation, and/or higher reverse breakdown voltage. The vast majority of the discrete (i.e., non-integrated) power devices are built using a vertical structure, whereas small-signal devices employ a lateral structure. With the vertical structure, the current rating of the device is proportional to its area, and the voltage blocking capability is achieved in the height of the die. With this structure, one of the connections of the device is located on the bottom of the semiconductor die.

1. Electrical Final Year 2014 Batch

2. PRACTICAL
SETUP
OF
POWER ELECTRONICS LAB

3. CONTENTS
1) SCR
2) TRAIC
3) GTO
4) BJT
5) IGBT
6) MOSFET
7) R-FIRING CKT
8) RC-FIRING CKT
9) UJT-FIRING CKT

4. SILICON CONTROLLED
RECTIFIER (SCR)
7000 v
5000 Amp

8. V-I Characteristics of SCR

9. APPLICATIONS OF SCR :-
• Speed control for motors
• Battery-charging regulator
• Temperature controller circuit
• Emergency-lighting system
• Temperature control for electric hot plate
• Dimmer switch for domestic lighting
• Dimmer control for stage lighting.

10. Triac
1200 V
1000 Amp

11. SYMBOL & LAYER DIAGRAM

12. V-I CHRACTERISTICS OF TRAIC

13. Applications of the TRIAC
 The TRIAC as a bidirectional thyristor has various
applications. Some of the popular applications of the
TRIAC are as follows:
(i) In speed control of single-phase ac series or universal motors.
(ii) In food mixers and portable drills.
(iii) In lamp dimming and heating control.
(iv) In zero-voltage switched ac relay.

14. GATE TURN OFF THYRISTOR
(GTO)
5000 v
3000 Amp

15. CIRCUIT SYMBOL AND STRUCTURE OF GTO

16. V-I CHRATERISTICS OF GTO

17. GTO Applications
• Counters
• Pulse generators
• Oscillators
• Voltage regulators

18. Bipolar Junction Transistor
(BJT)
1400 v
400 Amp

19. LAYER DIAGRAM

20. V-I CHARACTERISTIC OF BJT

21. Insulated Gate Bipolar
Transistor (IGBT) 1200 v
500 Amp

22. Vertical cross section of an IGBT

24. V-I characteristics of an IGBT

25. APPLICATIONS:
 The IGBT is mostly used in high-speed switching devices. They have
switching speeds greater than those of bipolar power transistors.
 Robot welding machine.
 Uninterruptible Power Supply.
 Motor control.

26. Metal Oxide
Semiconductor Field Effect
Transistor (MOSFET )
1000 v
50 Amp

28. Schematic construction of a MOSFET

30. V-I CHARATERISTIC OF MOSFET

31. Applications of Power Devices

32. R-FIRING CIRCUIT

33. R-C FIRING CIRCUIT

34. UJT TRIGRING CIRCUIT

35. UJT-Firing Circuit
&
Electronic Fan
Regulator

36. THE END
THANK YOU