Igbt Working

Basic Structure; Working: Industrial Importance; Switching Characteristics

1. IGBT Group Name: GA-7 Group Leader: Azfar Rasool 12-EL-04 Group Members: Musa Ali 12-EL-37 M.Imran 12-EL-30 Saba Nazeer 11-12EL-57

2. IGBT (Insulated Gate B ipolar Transistor) What does word stand for….. Combination of BJT and MOSFET {[(HOW)} Lab Symbol Detailed description of symbol

3. Construction and Basic Structure Revert the polarities and.. Check!

4. Changing to simplified circuit…

5. Working And Operation Controlling factor: Gate Voltage Called as voltage-controlled BJT Input current zero at gate; as insulated Input is MOSFET characteristics Output is BJT characteristics Threshold Voltage

6. Working And Operation npnp structure Thyristor Parasitic transistor and resistence no effect under normal operation Max collector current Parasitic transistor activates Thus parasitic thyristor activates Latch up condition dominates i.e. IGBT will remain on Cannot controlled by gate voltage

7. How do IGBT LOOK like…. 1RGT10075M12 Made in Italy 5EMK80N Made in China Internal Structure A Dissectional view of IGBT All of the IGBT’s related to any model do have the simplified circuit drawn on it.

8. Importance & Advantages of IGBT in Electrical & Electronics world Combine features of MOSFET & BJT under single device High current & High voltage Switching Applications, provides safe gateway Low on state voltage drop (MOSFET part) & High on state current density; so smaller chip size & low cost manufacturing & production Low voltage drop at input gate; so easily controlled compared to thyristors & BJT’s. High density current conduction provides excellent forward & reverse blocking capabalites . It can be used in every electronic and electrical circuits where high switch repletion is need.

9. Applications of IGBT’s in Electrical & Electronics World Switch Mode Power Supplies (SMPS) Safe controlling to work with high voltage or high current.

10. Uninterruptible Power Supplies (UPS) Old UPS gives audible irritating sound IGBT use in UPS gives it high dynamic range and low noise. Ex: China company HOMAGE UPS

11. Pulse Width Modulation (PWM) Increase or decrease the pulse width according to requirement and desire

12. Three Phase Drivers

13. Switching Characteristics of IGBT’s IGBT S witching T est Time Circuit Switching Characteristics similar to Power Mosfet Difference is; tailing collector current due to stored charge in N (negative) Drift region Tail current increases turn off loss Also increase the dead time between the two devices in half-bridge circuit Operates at -15V at gate to switch off

14. Turn off speed limited of IGBT (How) Lifetime stored charge or minority carriers in N(- ve ) drift-region Base is parasitic PNP transistor No External means to sweep the minority carriers from N(- ve ) drift region To improve Switching time N(+ ve ) buffer layer helps

15. References: Powered by google images Abdus Sattar 1XYS Corporation Text book: Electronic Device and Circuits by Floyd

16. Thank You

17. Any Queries