{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T18:28:21Z","timestamp":1777487301519,"version":"3.51.4"},"reference-count":38,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2025,2,24]],"date-time":"2025-02-24T00:00:00Z","timestamp":1740355200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Alliance for the Energy Transition (56)","award":["101072414 (E2GO)"],"award-info":[{"award-number":["101072414 (E2GO)"]}]},{"name":"Alliance for the Energy Transition (56)","award":["ATE_BI_2023_02_CALG (2)"],"award-info":[{"award-number":["ATE_BI_2023_02_CALG (2)"]}]},{"name":"Alliance for the Energy Transition (56)","award":["ATE_BI_2024_01_CALG (1)"],"award-info":[{"award-number":["ATE_BI_2024_01_CALG (1)"]}]},{"name":"Alliance for the Energy Transition (56)","award":["2021.08965.BD"],"award-info":[{"award-number":["2021.08965.BD"]}]},{"name":"Marie Sklodowska-Curie Doctoral Networks","award":["101072414 (E2GO)"],"award-info":[{"award-number":["101072414 (E2GO)"]}]},{"name":"Marie Sklodowska-Curie Doctoral Networks","award":["ATE_BI_2023_02_CALG (2)"],"award-info":[{"award-number":["ATE_BI_2023_02_CALG (2)"]}]},{"name":"Marie Sklodowska-Curie Doctoral Networks","award":["ATE_BI_2024_01_CALG (1)"],"award-info":[{"award-number":["ATE_BI_2024_01_CALG (1)"]}]},{"name":"Marie Sklodowska-Curie Doctoral Networks","award":["2021.08965.BD"],"award-info":[{"award-number":["2021.08965.BD"]}]},{"name":"scholarship","award":["101072414 (E2GO)"],"award-info":[{"award-number":["101072414 (E2GO)"]}]},{"name":"scholarship","award":["ATE_BI_2023_02_CALG (2)"],"award-info":[{"award-number":["ATE_BI_2023_02_CALG (2)"]}]},{"name":"scholarship","award":["ATE_BI_2024_01_CALG (1)"],"award-info":[{"award-number":["ATE_BI_2024_01_CALG (1)"]}]},{"name":"scholarship","award":["2021.08965.BD"],"award-info":[{"award-number":["2021.08965.BD"]}]},{"name":"scholarship","award":["101072414 (E2GO)"],"award-info":[{"award-number":["101072414 (E2GO)"]}]},{"name":"scholarship","award":["ATE_BI_2023_02_CALG (2)"],"award-info":[{"award-number":["ATE_BI_2023_02_CALG (2)"]}]},{"name":"scholarship","award":["ATE_BI_2024_01_CALG (1)"],"award-info":[{"award-number":["ATE_BI_2024_01_CALG (1)"]}]},{"name":"scholarship","award":["2021.08965.BD"],"award-info":[{"award-number":["2021.08965.BD"]}]},{"name":"FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","award":["101072414 (E2GO)"],"award-info":[{"award-number":["101072414 (E2GO)"]}]},{"name":"FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","award":["ATE_BI_2023_02_CALG (2)"],"award-info":[{"award-number":["ATE_BI_2023_02_CALG (2)"]}]},{"name":"FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","award":["ATE_BI_2024_01_CALG (1)"],"award-info":[{"award-number":["ATE_BI_2024_01_CALG (1)"]}]},{"name":"FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","award":["2021.08965.BD"],"award-info":[{"award-number":["2021.08965.BD"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Energies"],"abstract":"<jats:p>This article presents the design and implementation of a DC\u2013DC power converter for application in electric vehicle (EV) fast-charging systems. The prototype is of the resonant LLC type and consists of a high-power transformer operating at high frequency, which is an essential feature for the adequate behavior of the EV fast-charging system as a whole. As demonstrated throughout the article, by using this converter topology as well as its specific operating modes, such as for achieving zero-voltage switching (ZVS) and zero-current switching (ZCS), it is possible to enhance efficiency by reducing conduction and switching losses as well as to increase power density. The details of the high-power high-frequency transformer (HFT), considering different designs, are presented and discussed. With the implemented laboratorial prototype fully developed with silicon carbide (SiC) power semiconductor devices, it was possible to demonstrate and validate the main features of the resonant LLC converter, including high efficiency, under distinct conditions of operation.<\/jats:p>","DOI":"10.3390\/en18051099","type":"journal-article","created":{"date-parts":[[2025,2,24]],"date-time":"2025-02-24T07:46:57Z","timestamp":1740383217000},"page":"1099","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Design and Implementation of a DC\u2013DC Resonant LLC Converter for Electric Vehicle Fast Chargers"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-3065-2221","authenticated-orcid":false,"given":"Joao","family":"Rocha","sequence":"first","affiliation":[{"name":"ALGORITMI Research Centre, LASI, University of Minho, 4800-058 Guimar\u00e3es, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2898-8685","authenticated-orcid":false,"given":"Saghir","family":"Amin","sequence":"additional","affiliation":[{"name":"ALGORITMI Research Centre, LASI, University of Minho, 4800-058 Guimar\u00e3es, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4888-6827","authenticated-orcid":false,"given":"Sergio","family":"Coelho","sequence":"additional","affiliation":[{"name":"ALGORITMI Research Centre, LASI, University of Minho, 4800-058 Guimar\u00e3es, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-9681-7889","authenticated-orcid":false,"given":"Gon\u00e7alo","family":"Rego","sequence":"additional","affiliation":[{"name":"ALGORITMI Research Centre, LASI, University of Minho, 4800-058 Guimar\u00e3es, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9195-1239","authenticated-orcid":false,"given":"Joao L.","family":"Afonso","sequence":"additional","affiliation":[{"name":"ALGORITMI Research Centre, LASI, University of Minho, 4800-058 Guimar\u00e3es, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6640-8955","authenticated-orcid":false,"given":"Vitor","family":"Monteiro","sequence":"additional","affiliation":[{"name":"ALGORITMI Research Centre, LASI, University of Minho, 4800-058 Guimar\u00e3es, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,2,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"53614","DOI":"10.1109\/ACCESS.2022.3175585","article-title":"Comprehensive Assessment of Electric Vehicle Development, Deployment, and Policy Initiatives to Reduce GHG Emissions: Opportunities and Challenges","volume":"10","author":"Sathiyan","year":"2022","journal-title":"IEEE Access"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"58","DOI":"10.3390\/wevj5010058","article-title":"Governing and Innovation: The Transition to E-Mobility\u2014A Dutch Perspective","volume":"5","year":"2012","journal-title":"World Electr. Veh. J."},{"key":"ref_3","unstructured":"International Energy Agency (IEA) (2024, November 18). Trends in Electric Cars\u2014Global EV Outlook 2024\u2014Analysis. Available online: https:\/\/www.iea.org\/reports\/global-ev-outlook-2024\/trends-in-electric-cars."},{"key":"ref_4","first-page":"244","article-title":"Three-Level Zero-Voltage Transition Interleaved Buck Converter with DC Transformer-based Isolation for EV Fast Charging Stations","volume":"Volume 716","author":"Ferrada","year":"2024","journal-title":"Technological Innovation for Human-Centric Systems, Proceedings of the 15th IFIP WG 5.5\/SOCOLNET Advanced Doctoral Conference on Computing, Electrical and Industrial Systems, DoCEIS 2024, Caparica, Portugal, 3\u20135 July 2024"},{"key":"ref_5","unstructured":"Redondo-Iglesias, E., Vinot, E., Venet, P., and Pelissier, S. (2019, January 19\u201322). Electric Vehicle Range and Battery Lifetime: A Trade-Off. Proceedings of the EVS32, Lyon, France. Available online: https:\/\/hal.science\/hal-02143273."},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Omahne, V., Knez, M., and Obrecht, M. (2021). Social Aspects of Electric Vehicles Research\u2014Trends and Relations to Sustainable Development Goals. World Electr. Veh. J., 12.","DOI":"10.3390\/wevj12010015"},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Bisoyi, S., Terang, P., Pathak, L., Singh, A., Singh, S., and Khare, R. (2022). Design of an EV Charging System with Improved Performance. Sustainable Energy and Technological Advancements, Proceedings of the ISSETA Shillong, India, 24\u201325 September 2021, Springer.","DOI":"10.1007\/978-981-16-9033-4_40"},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Trivedi, N., Gujar, N.S., Sarkar, S., and Pundir, S.P.S. (2018, January 13\u201314). Different fast charging methods and topologies for EV charging. Proceedings of the 2018 IEEMA Engineer Infinite Conference (eTechNxT), New Delhi, India.","DOI":"10.1109\/ETECHNXT.2018.8385313"},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Saadaoui, A., Ouassaid, M., and Maaroufi, M. (2023). Overview of Integration of Power Electronic Topologies and Advanced Control Techniques of Ultra-Fast EV Charging Stations in Standalone Microgrids. Energies, 16.","DOI":"10.3390\/en16031031"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"40753","DOI":"10.1109\/ACCESS.2022.3166935","article-title":"A Comprehensive Review of Power Converter Topologies and Control Methods for Electric Vehicle Fast Charging Applications","volume":"10","author":"Safayatullah","year":"2022","journal-title":"IEEE Access"},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Zhou, K., Wu, Y., Wu, X., Sun, Y., Teng, D., and Liu, Y. (2023). Research and Development Review of Power Converter Topologies and Control Technology for Electric Vehicle Fast-Charging Systems. Electronics, 12.","DOI":"10.3390\/electronics12071581"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"7486","DOI":"10.1109\/JESTPE.2020.3028057","article-title":"Isolated and Nonisolated DC-to-DC Converters for Medium-Voltage DC Networks: A Review","volume":"9","author":"Alhurayyis","year":"2021","journal-title":"IEEE J. Emerg. Sel. Top. Power Electron."},{"key":"ref_13","unstructured":"Wei, C., Hu, Z., Zhang, F., Shao, J., and Narain, A. (2022, January 10\u201312). A SiC Based 30kW Three-Phase Interleaved LLC Resonant Converter for EV Fast Charger. Proceedings of the PCIM Europe 2022\u2014International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management, N\u00fcrnberg, Germany."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Sheng, B., Zhou, X., Liu, W., Chen, Y., Liu, Y.-F., and Sen, P.C. (2020, January 11\u201315). Analysis and Control of Three-Phase Interleaved SCC-LLC Resonant Converter Load Sharing Considering Component Tolerance. Proceedings of the 2020 IEEE Energy Conversion Congress and Exposition (ECCE), Detroit, MI, USA.","DOI":"10.1109\/ECCE44975.2020.9236113"},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Trung, T.H., Linh, N.H., Canh, H.V., and Pham, P.V. (2022). Unbalanced three-phase interleaved LLC resonant converter: Current phase angle balancing technique. Int. J. Power Electron. Drive Syst., 13.","DOI":"10.11591\/ijpeds.v13.i2.pp1056-1067"},{"key":"ref_16","unstructured":"Hasseni, S. (2021). Design and Control of Bidirectional Dual Active Bridge DC-DC Converter for Dynamic Electric Vehicle Charging and Vehicle-to-Grid Operations. [Ph.D. Thesis, Glasgow Caledonian Univesiry]."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"216","DOI":"10.30574\/ijsra.2024.12.1.0768","article-title":"Analysis of dual active bridge-based on-board battery charger for electric and hybrid vehicles","volume":"12","author":"Eyvazi","year":"2024","journal-title":"Int. J. Sci. Res. Arch."},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Mathew, A., Prasad, U.R., Madhu, G.M., Naik, N., Vyjayanthi, C., and Subudhi, B. (2022, January 21\u201322). Performance Analysis of a Dual Active Bridge Converter in EV Charging Applications. Proceedings of the 2022 International Conference for Advancement in Technology (ICONAT), Goa, India.","DOI":"10.1109\/ICONAT53423.2022.9725886"},{"key":"ref_19","unstructured":"Coelho, S., Sousa, T.J.C., Monteiro, V.D.F., Machado, L., Afonso, J.L., and Couto, C. (2024, November 18). Comparative Analysis and Validation of Different Modulation Strategies for a Dual Active Bridge Converter. Available online: https:\/\/repositorium.sdum.uminho.pt\/handle\/1822\/80157."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"48774","DOI":"10.1109\/ACCESS.2020.2977663","article-title":"Multi-Level DC-DC Converter for E-Mobility Charging Stations","volume":"8","author":"Lim","year":"2020","journal-title":"IEEE Access"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"2533","DOI":"10.1109\/TIE.2010.2049719","article-title":"Recent Advances and Industrial Applications of Multilevel Converters","volume":"57","author":"Kouro","year":"2010","journal-title":"IEEE Trans. Ind. Electron."},{"key":"ref_22","unstructured":"Ngo, T., and Nguyen-Quang, N. (2016, January 2\u20134). Improving Battery Charging Efficiency with Soft Switching Technique. Proceedings of the 5th World Conference on Applied Sciences, Engineering & Technology, Ho Chi Minh City, Vietnam."},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Kim, D.-H., Kim, M.-S., Hussain Nengroo, S., Kim, C.-H., and Kim, H.-J. (2019). LLC Resonant Converter for LEV (Light Electric Vehicle) Fast Chargers. Electronics, 8.","DOI":"10.3390\/electronics8030362"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"33037","DOI":"10.1109\/ACCESS.2023.3263486","article-title":"High-Efficiency LLC Resonant Converter with Wide Output Range of 200\u20131000 V for DC-Connected EVs Ultra-Fast Charging Stations","volume":"11","author":"Elezab","year":"2023","journal-title":"IEEE Access"},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Israr, M., and Samuel, P. (2023, January 6\u20138). Study and Design of DC-DC LLC Full Bridge Converter for Electric Vehicle Charging Application. Proceedings of the 5th International Conference on Power, Control & Embeded Systems (IPSCES), Allahabad, India.","DOI":"10.1109\/ICPCES57104.2023.10076234"},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Rocha, J., Amin, S., Rego, G., and Monteiro, V. (2024, January 5). Step-by-Step Design of a LLC Resonant Converter for EV Fast Charging Applications. Proceedings of the 2024 8th International Young Engineers Forum on Electrical and Computer Engineering (YEF-ECE), Caparica\/Lisbon, Portugal.","DOI":"10.1109\/YEF-ECE62614.2024.10625506"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"21","DOI":"10.1109\/MIE.2016.2549981","article-title":"Resonant Power Converters: An Overview with Multiple Elements in the Resonant Tank Network","volume":"10","author":"Delgado","year":"2016","journal-title":"IEEE Ind. Electron. Mag."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1644","DOI":"10.1109\/TIE.2009.2031950","article-title":"Zero-Voltage and Zero-Current-Switching PWM Combined Three-Level DC-DC Converter","volume":"57","author":"Liu","year":"2010","journal-title":"IEEE Trans. Ind. Electron."},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Lalitha, A.S., Chakraborty, S., and Kumar, S.S. (2022, January 27\u201329). A Zero Voltage Switching Based Soft Switching Boost DC-DC Converter for Vehicle to Grid Applications with Enhanced Energy Efficiency. Proceedings of the 2022 3rd International Conference for Emerging Technology (INCET), Belgaum, India.","DOI":"10.1109\/INCET54531.2022.9824207"},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Cittanti, D., Gammeter, C., Huber, J., and Bojoi, R. (2022). A Simplified Hard-Switching Loss Model for Fast-Switching Three-Level T-Type SiC Bridge-Legs. Electronics, 11.","DOI":"10.3390\/electronics11111686"},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Abdulhakeem, M., Sahid, M.R., and Sutikno, T. (2006). Overview of Soft-Switching DC-DC Converters. Int. J. Power Electron. Drive Syst. IJPEDS, 9.","DOI":"10.11591\/ijpeds.v9.i4.pp2006-2018"},{"key":"ref_32","doi-asserted-by":"crossref","unstructured":"Riegler, B., and M\u00fctze, A. (2021, January 10\u201314). Volume Comparison of Passive Components for Hard-Switching Current- and Voltage-Source-Inverters. Proceedings of the 2021 IEEE Energy Conversion Congress and Exposition (ECCE), Vancouver, BC, Canada.","DOI":"10.1109\/ECCE47101.2021.9595392"},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Ebli, M., and Pfost, M. (2017, January 13\u201314). An analysis of the switching behavior of GaN-HEMTs. Proceedings of the 2017 International Symposium on Signals, Circuits, and Systems (ISSCS), Iasi, Romania.","DOI":"10.1109\/ISSCS.2017.8034939"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"112","DOI":"10.1109\/TPEL.2012.2199520","article-title":"Soft-Switching DC-DC Converter With a Full ZVS Range and Reduced Output Filter for High-Voltage Applications","volume":"28","author":"Lee","year":"2023","journal-title":"IEEE Trans. Power Electron."},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Nadolny, Z. (2023). Design and Optimization of Power Transformer Diagnostics. Energies, 16.","DOI":"10.3390\/en16186466"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"1645","DOI":"10.1002\/cta.2681","article-title":"A new design strategy for DC-DC LLC resonant converter: Concept, modeling, and fabrication","volume":"47","author":"Khosrogorji","year":"2019","journal-title":"Int. J. Circuit Theory Appl."},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Sucameli, M., and Adragna, C. (2023). LLC Resonant Converters as Isolated Power Factor Corrector Pre-Regulators\u2014Analysis and Performance Evaluation. Energies, 16.","DOI":"10.3390\/en16207114"},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"Liu, Y.-C., Chen, C., Chen, K.-D., Syu, Y.-L., and Tsai, M.-C. (2019). High-Frequency LLC Resonant Converter with GaN Devices and Integrated Magnetics. Energies, 12.","DOI":"10.3390\/en12091781"}],"container-title":["Energies"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1996-1073\/18\/5\/1099\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T16:41:30Z","timestamp":1760028090000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1996-1073\/18\/5\/1099"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,2,24]]},"references-count":38,"journal-issue":{"issue":"5","published-online":{"date-parts":[[2025,3]]}},"alternative-id":["en18051099"],"URL":"https:\/\/doi.org\/10.3390\/en18051099","relation":{},"ISSN":["1996-1073"],"issn-type":[{"value":"1996-1073","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,2,24]]}}}