Power Semiconductor Devices
Introduction
Today there are many power semiconductor devices used in different applications of power conversion. The diode is one of the oldest semiconductors devices and is still wildly used today in power electronics. Diodes are found in virtually all power converts in one form or another. For this reason our discussion will be focused on the application of power diodes. Power Diodes are two terminal electronic devices that permit current flow in predominantly one direction. Diodes are composed of differently doped silicon or germanium bounded together at a junction.
Purpose
As an Electrical Engineering specializing in Power Electronics it is important to understanding the application of different types of diodes in power electronics. The technology behind the development of pn junctions and solid state devices is continuously advancing. This is why it is important to be informed of the most modern advances of one of the world’s oldest power semiconductor devices. This paper will focus on the construction and ratings of various types of power diodes to convey the importance diodes have power electronics.
Power Diodes:
Power diodes are successors to the very first semiconductor devices. Power diodes are mainly used as uncontrolled rectifiers to convert single-phase or three- phase AC voltage to a rippled DC voltage. Typically they are constructed of a mixture of differently doped silicon or germanium. Most common are the silicon diodes because they can operate at higher currents and junction temperatures then germanium diodes. All diodes are devices that conduct current in only one direction. Whenever the voltage on the anode is positive with respect to the cathode, the dio...
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...e a diode that will satisfy the requirements of the circuit while increasing overall circuit efficiency and maintaining reliability. Through improved modern design techniques diodes are no longer a weak component, and are becoming more important in power electronics with the increase demand for higher power quality and power efficiency.
Works Cited:
N. Mohan, T.M. Undeland, W.P. Robbins, “Power Electronics”, John Wiley & Sons, Inc. © 2003
Timothy L. Skvarenina, “The Power Electronics Handbook” CRC Press LLC © 2002
Materials Research Society Symposium Proceedings Volume 483, “Power Semiconductor Materials and Devices” Materials Research Society © 1998
“Dura-Bilt5i MV Engineering Reference Book”, GE Toshiba Automation Systems, U.S.A. © 2003
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4. Fourth Stage[t3-t4](Fig.10) : At time t3, CM finished energy get transfer at that instant the diode D1 is blocked. The energy transfer to output maintain till t4 till power switch is turn on.
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