Accurate ZVS Analysis of a Full-Bridge T-Type Resonant Converter for a 20-kW Unfolding-Based AC-DC Topology
Unfolding-based single-stage ac-dc converters offer benefits in terms of efficiency and power density due to the low-frequency operation of the Unfolder, resulting in negligible switching losses. However, the operation of the Unfolder results in time-varying dc voltages at the input of the subsequen...
Saved in:
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
IEEE
2024-01-01
|
| Series: | IEEE Open Journal of Power Electronics |
| Subjects: | |
| Online Access: | https://ieeexplore.ieee.org/document/10530476/ |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1850211396860510208 |
|---|---|
| author | SHUBHANGI GURUDIWAN Aditya Zade Hongjie Wang Regan Zane |
| author_facet | SHUBHANGI GURUDIWAN Aditya Zade Hongjie Wang Regan Zane |
| author_sort | SHUBHANGI GURUDIWAN |
| collection | DOAJ |
| description | Unfolding-based single-stage ac-dc converters offer benefits in terms of efficiency and power density due to the low-frequency operation of the Unfolder, resulting in negligible switching losses. However, the operation of the Unfolder results in time-varying dc voltages at the input of the subsequent dc-dc converter, complicating its soft-switching analysis. The complication is further enhanced due to the nonlinear nature of the output capacitance (<inline-formula><tex-math notation="LaTeX">$C_\text{oss}$</tex-math></inline-formula>) of MOSFETs employed in the dc-dc converter. Furthermore, unlike two-stage topologies with a constant dc-link voltage, as seen in high-frequency grid-tied converters, grid voltage fluctuations also impact the dc input voltages of the dc-dc converter in unfolding-based systems. This work comprehensively analyzes the soft-switching phenomenon in the T-type primary bridge-based dc-dc converter used in unfolding-based topologies, considering all the aforementioned challenges. An energy-based methodology is proposed to determine the minimum zero-voltage switching (ZVS) current and ZVS time during various switching transitions of the T-type bridge. It is shown that the existing literature on the ZVS analysis of the T-type bridge-based resonant dc-dc converter, relying solely on capacitive energy considerations, substantially underestimates the required ZVS current values, with errors reaching up to 50%. The proposed analysis is verified through both simulation and hardware testing. The hardware testing is conducted on a 20-kW 3-<inline-formula><tex-math notation="LaTeX">$\phi$</tex-math></inline-formula> unfolding-based ac-dc converter designed for high-power electric vehicle battery charging applications. The ZVS analysis is verified at various grid angles with the proposed analysis ensuring a complete ZVS operation of the ac-dc system throughout the grid cycle. |
| format | Article |
| id | doaj-art-a62603526d62467ca47c506dfeff907f |
| institution | OA Journals |
| issn | 2644-1314 |
| language | English |
| publishDate | 2024-01-01 |
| publisher | IEEE |
| record_format | Article |
| series | IEEE Open Journal of Power Electronics |
| spelling | doaj-art-a62603526d62467ca47c506dfeff907f2025-08-20T02:09:34ZengIEEEIEEE Open Journal of Power Electronics2644-13142024-01-01569270810.1109/OJPEL.2024.340025610530476Accurate ZVS Analysis of a Full-Bridge T-Type Resonant Converter for a 20-kW Unfolding-Based AC-DC TopologySHUBHANGI GURUDIWAN0https://orcid.org/0009-0000-9717-9737Aditya Zade1https://orcid.org/0009-0008-0633-8797Hongjie Wang2https://orcid.org/0000-0002-0162-7812Regan Zane3https://orcid.org/0000-0003-1742-9949Department of Electrical and Computer Engineering, Utah State University, Logan, UT, USADepartment of Electrical and Computer Engineering, Utah State University, Logan, UT, USADepartment of Electrical and Computer Engineering, Utah State University, Logan, UT, USADepartment of Electrical and Computer Engineering, Utah State University, Logan, UT, USAUnfolding-based single-stage ac-dc converters offer benefits in terms of efficiency and power density due to the low-frequency operation of the Unfolder, resulting in negligible switching losses. However, the operation of the Unfolder results in time-varying dc voltages at the input of the subsequent dc-dc converter, complicating its soft-switching analysis. The complication is further enhanced due to the nonlinear nature of the output capacitance (<inline-formula><tex-math notation="LaTeX">$C_\text{oss}$</tex-math></inline-formula>) of MOSFETs employed in the dc-dc converter. Furthermore, unlike two-stage topologies with a constant dc-link voltage, as seen in high-frequency grid-tied converters, grid voltage fluctuations also impact the dc input voltages of the dc-dc converter in unfolding-based systems. This work comprehensively analyzes the soft-switching phenomenon in the T-type primary bridge-based dc-dc converter used in unfolding-based topologies, considering all the aforementioned challenges. An energy-based methodology is proposed to determine the minimum zero-voltage switching (ZVS) current and ZVS time during various switching transitions of the T-type bridge. It is shown that the existing literature on the ZVS analysis of the T-type bridge-based resonant dc-dc converter, relying solely on capacitive energy considerations, substantially underestimates the required ZVS current values, with errors reaching up to 50%. The proposed analysis is verified through both simulation and hardware testing. The hardware testing is conducted on a 20-kW 3-<inline-formula><tex-math notation="LaTeX">$\phi$</tex-math></inline-formula> unfolding-based ac-dc converter designed for high-power electric vehicle battery charging applications. The ZVS analysis is verified at various grid angles with the proposed analysis ensuring a complete ZVS operation of the ac-dc system throughout the grid cycle.https://ieeexplore.ieee.org/document/10530476/Electric vehicle (EV) charging<named-content xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:ali="http://www.niso.org/schemas/ali/1.0/" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" content-type="math" xlink:type="simple"> <inline-formula> <tex-math notation="LaTeX">$C_\text{oss}$</tex-math> </inline-formula> </named-content> energy estimationmulti-level converternonlinear capacitanceresonant converterT-type converter |
| spellingShingle | SHUBHANGI GURUDIWAN Aditya Zade Hongjie Wang Regan Zane Accurate ZVS Analysis of a Full-Bridge T-Type Resonant Converter for a 20-kW Unfolding-Based AC-DC Topology IEEE Open Journal of Power Electronics Electric vehicle (EV) charging <named-content xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:ali="http://www.niso.org/schemas/ali/1.0/" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" content-type="math" xlink:type="simple"> <inline-formula> <tex-math notation="LaTeX">$C_\text{oss}$</tex-math> </inline-formula> </named-content> energy estimation multi-level converter nonlinear capacitance resonant converter T-type converter |
| title | Accurate ZVS Analysis of a Full-Bridge T-Type Resonant Converter for a 20-kW Unfolding-Based AC-DC Topology |
| title_full | Accurate ZVS Analysis of a Full-Bridge T-Type Resonant Converter for a 20-kW Unfolding-Based AC-DC Topology |
| title_fullStr | Accurate ZVS Analysis of a Full-Bridge T-Type Resonant Converter for a 20-kW Unfolding-Based AC-DC Topology |
| title_full_unstemmed | Accurate ZVS Analysis of a Full-Bridge T-Type Resonant Converter for a 20-kW Unfolding-Based AC-DC Topology |
| title_short | Accurate ZVS Analysis of a Full-Bridge T-Type Resonant Converter for a 20-kW Unfolding-Based AC-DC Topology |
| title_sort | accurate zvs analysis of a full bridge t type resonant converter for a 20 kw unfolding based ac dc topology |
| topic | Electric vehicle (EV) charging <named-content xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:ali="http://www.niso.org/schemas/ali/1.0/" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" content-type="math" xlink:type="simple"> <inline-formula> <tex-math notation="LaTeX">$C_\text{oss}$</tex-math> </inline-formula> </named-content> energy estimation multi-level converter nonlinear capacitance resonant converter T-type converter |
| url | https://ieeexplore.ieee.org/document/10530476/ |
| work_keys_str_mv | AT shubhangigurudiwan accuratezvsanalysisofafullbridgettyperesonantconverterfora20kwunfoldingbasedacdctopology AT adityazade accuratezvsanalysisofafullbridgettyperesonantconverterfora20kwunfoldingbasedacdctopology AT hongjiewang accuratezvsanalysisofafullbridgettyperesonantconverterfora20kwunfoldingbasedacdctopology AT reganzane accuratezvsanalysisofafullbridgettyperesonantconverterfora20kwunfoldingbasedacdctopology |