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 Lecture 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%)

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

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

Chapter One A Review of Power electronics Applications

Chapter One

AC-to DC Converter

Chapter One AC-to DC Converter

Chapter One AC Voltage Controllers

Chapter One AC Voltage Controllers

Chapter One DC-to AC Inverters

Chapter One DC-to AC Inverters

Chapter One DC-to AC Inverters

Chapter One DC-to-AC Converter

Chapter One DC-to-AC Converter

Chapter One DC-to-AC Converter

Chapter One DC-to DC Converter

Chapter One AC-to AC Converter

Chapter One Line Commutated Inverter

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