1. POWER ELECTRONICS Instructor: Eng.Moayed N. EL Mobaied The Islamic University of Gaza Faculty of Engineering Electrical Engineering Department بسم الله الرحمن الرحيم EELE 5450 — Fall 2009-2010 Lecture 2

2. Chapter One Question: What are power electronic devices? Answer: Fast switches that can handle high voltages and currents Question: Why do we need these fast switches? Answer: To efficiently convert AC to DC, DC to DC, or DC to AC, or to efficiently control average power flow. (Efficiently usually means greater than 80% – 90%)

3. A switch Rugged, reliable, efficient, long lived, but not very fast Chapter One

4. is fast − can open and close instantly (thus no switching losses), and at a high rate (i.e., operating frequency) when closed, can conduct any amount of current with no internal voltage drop (thus no conduction losses) when open, will conduct no current and can withstand any voltage without breakdown will be unidirectional or asymmetric (that is an inherent property of power electronic devices, and we can always place two switches in antiparallel and use blocking diodes to prevent backward conduction) The ideal power electronic device is a perfect switch that

5. Chapter One A Review of Power electronics Applications

6. Chapter One

10. AC-to DC Converter

11. Chapter One AC-to DC Converter

12. Chapter One AC Voltage Controllers

13. Chapter One AC Voltage Controllers

14. Chapter One DC-to AC Inverters

15. Chapter One DC-to AC Inverters

16. Chapter One DC-to AC Inverters

17. Chapter One DC-to-AC Converter

18. Chapter One DC-to-AC Converter

19. Chapter One DC-to-AC Converter

20. Chapter One DC-to DC Converter

21. Chapter One AC-to AC Converter

22. Chapter One Line Commutated Inverter

23. H.W#1 End of Lecture **** Eng.moayed In no more than one page : Write about one of modern Applications of Power electronic converters.