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Title: Optimization of an Unregulated Low-Q Resonant Isolated DC-DC Stage for Low-Power AC-AC Converters
Low-power line-frequency transformers are common across several applications, but these transformers are found to have large standby losses, low efficiencies, large weights, and high costs. In this paper we optimize a power conversion stage for this and other applications where an unregulated, isolated converter is needed. The selected topology uses low-impedance passives to reduce their size; to address this case we analyze operation of a lower-Q resonant tank. Lastly, because of the application of low-power line-frequency transformers, we optimize around a typical usage cycle to minimize the yearly average power loss. For the application of a Class 2 line-frequency transformer, model results are accurate to simulation by within 12.1%, and optimization produced a design that was experimentally validated to achieve a yearly average power loss of 285.1 mW, a peak efficiency of 99.26% and a standby loss of 155 mW.  more » « less
Award ID(s):
1820089 1822140
PAR ID:
10531576
Author(s) / Creator(s):
;
Publisher / Repository:
IEEE
Date Published:
ISSN:
2151-1004
ISBN:
979-8-3503-0723-8
Page Range / eLocation ID:
1 to 8
Subject(s) / Keyword(s):
Transformers Power electronics Topology DC-DC converter unregulated DC-DC converter
Format(s):
Medium: X
Location:
Lahore, Pakistan
Sponsoring Org:
National Science Foundation
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