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Title: Nonlinear Capacitance-Based Accurate ZVS Analysis for Full-Bridge T-Type Resonant Converters
To optimize the utilization of a T-type bridge structure in resonant converters, one must thoroughly examine the soft-switching criteria specific to the T-type configuration. This work proposes an energy-based method to determine the softs-witching requirements of a T-type bridge during its various switching transitions. The study estimates the minimum required zero voltage switching (ZVS) current while considering the nonlinearity and voltage dependence associated with the output capacitance of MOSFETs. Moreover, this paper demonstrates that existing studies on ZVS analysis for T-type bridge-based resonant dc-dc converters, which rely only on capacitive energy considerations, significantly underestimate the necessary ZVS current values, with errors as high as 50%. Simulation and hardware results on a T-type primary bridge circuit validate the accuracy of the proposed minimum ZVS current calculation. Hardware tests are conducted on a T-type bridge in a 20 kW electric vehicle charger.  more » « less
Award ID(s):
2239169
PAR ID:
10617221
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
IEEE
Date Published:
ISBN:
979-8-3503-7606-7
Page Range / eLocation ID:
3288 to 3295
Format(s):
Medium: X
Location:
Phoenix, AZ, USA
Sponsoring Org:
National Science Foundation
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