Title page for ETD etd-173510281975580


Type of Document Dissertation
Author Zhang, Michael Tao
URN etd-173510281975580
Title Electrical, Thermal, and EMI Designs of High-Density, Low-Profile Power Supplies
Degree PhD
Department Electrical and Computer Engineering
Advisory Committee
Advisor Name Title
Boroyevich, Dushan
Chang, Lay Nam
Chen, Dan Y.
Nelson, Douglas J.
Jovanovic, Milan M. Committee Co-Chair
Lee, Fred C. Committee Co-Chair
Keywords
  • none
Date of Defense 1998-02-17
Availability unrestricted
Abstract
This work presents the analyses and designs of

high-density, low-profile power supplies, including the

electrical, thermal, and EMI aspects. Emphasis is placed

on forward and flyback converters. The efficiency

improvements of employing synchronous rectification

are theoretically derived and experimentally verified in

forward and flyback converters. The performances of

synchronous rectifiers in forward converters are

analyzed with regards to transformer reset and SR

driven method. The effectiveness of synchronous

rectification in flyback converters is evaluated in various

operation modes and control schemes. The paralleling

techniques utilized to realize high-density, low-profile

power conversion are presented. Current sharing in

transformer paralleling is addressed and evaluated in

forward topology. The performance and the operation

principles of one-choke and two-choke interleaved

forward converters are analyzed. The thermal

management of high-density power supplies in sealed

enclosures is optimized using computational fluid

dynamics simulations. The theoretical limit of power

density due to thermal constraint is determined. In

addition, the thermal-design optimization guidelines are

given and verified experimentally. A systematic

methodology is developed to facilitate the analysis and

design of conducted EMI problems in high-density

power supplies. Partial element equivalent circuit method

is employed for parasitic parameter extraction. Layout

and packaging are optimized to minimize conducted EMI

noises. Noise predictions by Saber simulations are

confirmed by experimental measurements.

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  append.pdf 49.03 Kb 00:00:13 00:00:07 00:00:06 00:00:03 < 00:00:01
  chapter1.pdf 23.38 Kb 00:00:06 00:00:03 00:00:02 00:00:01 < 00:00:01
  chapter2.pdf 437.86 Kb 00:02:01 00:01:02 00:00:54 00:00:27 00:00:02
  chapter3.pdf 477.64 Kb 00:02:12 00:01:08 00:00:59 00:00:29 00:00:02
  chapter4.pdf 229.72 Kb 00:01:03 00:00:32 00:00:28 00:00:14 00:00:01
  chapter5.pdf 642.88 Kb 00:02:58 00:01:31 00:01:20 00:00:40 00:00:03
  chapter6.pdf 10.64 Kb 00:00:02 00:00:01 00:00:01 < 00:00:01 < 00:00:01
  etd.pdf 39.19 Kb 00:00:10 00:00:05 00:00:04 00:00:02 < 00:00:01
  referenc.pdf 30.39 Kb 00:00:08 00:00:04 00:00:03 00:00:01 < 00:00:01
  vita.pdf 4.62 Kb 00:00:01 < 00:00:01 < 00:00:01 < 00:00:01 < 00:00:01

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