European Research Council Consolidator Grant (ERC CoG) Project
More than a century ago, the invention of alternating current (AC) transformers made AC the preferred choice over the direct current (DC) technologies. Line AC transformers are bulky but simple and reliable devices, made out of copper and iron, providing voltage adaptation and galvanic isolation in AC power systems.
Currently, DC technology is increasing its presence in AC power systems, enabled by progress in semiconductor devices and power electronics-based energy conversion. DC power distribution networks can effectively support energy transformation and high penetration of distributed energy resources and energy storage integration (both increasingly being DC by nature) in future energy systems. Despite this shift towards the DC power distribution networks, DC Transformer, offering AC transformer-like features (and beyond) does not exist, either conceptually or practically.
To enable the next (r)evolution in power systems, the EMPOWER project will develop the DC Transformer, a novel, flexible, highly efficient, compact, and reliable conversion principle for seamless energy routing in high-power DC distribution networks. Through a holistic approach, novel concepts, integration, and optimization, we will demonstrate new design paradigms for galvanically-isolated power conversion. Our approach relies on resonant conversion utilizing high-voltage semiconductor devices in combination with high-frequency magnetic materials. We propose a new approach for the DC Transformer, avoiding active power flow control and instead utilizing control effort for safety and protection. The DC Transformer will unify the functions of a power converter and a protection device into a single power electronics system, improving drastically the conversion efficiency, reliability, and power density in future DC power distribution networks. The success of this project will place Europe at the edge of reliable, efficient, and safe energy distribution and transmission technologies.
For those interested in preparing the ERC CoG application, the original project proposal files are here: Part B1 and Part B2.
The EMPOWER project-related publications:
Direct Current Transformer for MVDC Applications
D. Dujic; R. Pillon Barcelos
TUTORIAL at: 17th Brazilian Power Electronics Conference / 8th IEEE Southern Power Electronics Conference – COBEP/SPEC 2023, Florianopolis, Brazil, November, 26 – 29, 2023. Medium Voltage Direct Current Technologies
D. Dujic
KEYNOTE at: 17th Brazilian Power Electronics Conference / 8th IEEE Southern Power Electronics Conference – COBEP/SPEC 2023, Florianopolis, Brazil, November, 26 – 29, 2023. Scalability assessment of the parallel operation of direct current transformers
R. Pillon Barcelos; D. Dujic
CPSS Transactions on Power Electronics and Applications. 2023. DOI : 10.24295/CPSSTPEA.2023.0003. On Features of Direct Current Transformers
R. Pillon Barcelos; D. Dujic
2023. The 11th International Conference on Power Electronics – ICPE – ECCE Asia, Jeju, Korea, May 22 – 25, 2023. p. 1912-1918. DOI : 10.23919/ICPE2023-ECCEAsia54778.2023.10213885. Parallel Operation of Direct Current Transformers
R. Pillon Barcelos; D. Dujic
2023. PCIM Europe 2023, Nürnberg, Germany, May 9-11, 2023. p. 87-96. DOI : 10.30420/566091010. Power Reversal Algorithm for Resonant Direct Current Transformers for DC Networks
R. P. Barcelos; J. Kucka; D. Dujic
IEEE Access. 2022. Vol. 10, p. 127117-127127. DOI : 10.1109/ACCESS.2022.3225673. Winding Geometry Impact on High Power Medium Frequency Transformer Design
N. Djekanovic; D. Dujic
2022. 14th International Symposium on Industrial Electronics – INDEL 2022, Banja Luka, Bosnia and Herzegovina, November 9-11, 2022. Copper Pipes as Medium Frequency Transformer Windings
N. Djekanovic; D. Dujic
IEEE Access. 2022. Vol. 10, p. 109431-109445. DOI : 10.1109/ACCESS.2022.3214651. Design Optimization of a MW-level Medium Frequency Transformer
N. Djekanovic; D. Dujic
2022. PCIM Europe 2022, Nürnberg, Germany, May 10-12, 2022. DOI : 10.30420/565822101. SOFTGATE – An IGCT Gate Unit for Soft Switching
J. Kucka; D. Dujic
2022. PCIM Europe 2022, Nurnberg, Germany, May 10-12, 2022. DOI : 10.30420/565822047. Shoot-Through Protection for an IGCT-Based ZVS Resonant DC Transformer
J. Kucka; D. Dujic
IEEE Transactions on Industrial Electronics. 2022. p. 1-1. DOI : 10.1109/TIE.2022.3170614. Direct Current Transformer Impact on the DC Power Distribution Networks
R. P. Barcelos; D. Dujic
IEEE Transactions on Smart Grid. 2022. p. 1-1. DOI : 10.1109/TSG.2022.3162310. Modeling and Characterization of Natural-Convection Oil-Based Insulation for Medium Frequency Transformers
N. Djekanovic; D. Dujic
2022. IEEE Applied Power Electronics Conference and Exposition (APEC 2022), Houston, TX, USA, March 20-24, 2022. p. 604-610. DOI : 10.1109/APEC43599.2022.9773591. High Frequency Operation of Series-Connected IGCTs for Resonant Converters
G. Ulissi; U. Vemulapati; T. Stiasny; D. Dujic
IEEE Transactions on Power Electronics. 2021-12-02. Vol. 37, num. 5, p. 5664-5674. DOI : 10.1109/TPEL.2021.3132200. Current Limiting in Overload Conditions of an LLC-Converter-Based DC Transformer
J. Kucka; D. Dujic
IEEE Transactions on Power Electronics. 2021-02-18. Vol. 36, num. 9, p. 10660-10672. DOI : 10.1109/TPEL.2021.3060106. An IGCT Gate Unit for Zero-Voltage-Switching Resonant DC Transformer Applications
J. Kucka; D. Dujic
IEEE Transactions on Industrial Electronics. 2021. p. 1-1. DOI : 10.1109/TIE.2021.3128923. Nodal Impedance Assessment in DC Power Distribution Networks
R. Pillon Barcelos; D. Dujic
2021. 22nd IEEE Workshop on Control and Modeling for Power Electronics (COMPEL 2021), Virtual Event, November 2-5, 2021. DOI : 10.1109/COMPEL52922.2021.9646008. Thermally-Compensated Magnetic Core Loss Model for Time-Domain Simulations of Electrical Circuits
N. Djekanovic; M. Luo; D. Dujic
IEEE Transactions on Power Electronics. 2021. p. 1-1. DOI : 10.1109/TPEL.2021.3053303. Equal Loss Distribution in Duty-Cycle Controlled H-Bridge LLC Resonant Converters
J. Kucka; D. Dujic
IEEE Transactions on Power Electronics. 2021. Vol. 36, p. 4937-4941. DOI : 10.1109/TPEL.2020.3028879. Modeling and Integrating Losses of Magnetic Components Into Time-Domain Electric Circuit Simulations
N. Djekanovic; M. Luo; D. Dujic
2020. The 2020 International Power Electronics and Motion Conference – IPEMC 2020 ECCE Asia, Nanjing, China (virtual), Nov 29-Dec 02, 2020. p. 1055-1062. DOI : 10.1109/IPEMC-ECCEAsia48364.2020.9367883. Smooth Power Direction Transition of a Bidirectional LLC Resonant Converter for DC Transformer Applications
J. Kucka; D. Dujic
IEEE Transactions on Power Electronics. 2020. p. 1-1. DOI : 10.1109/TPEL.2020.3038467. Integrated Simulation Approach to Loss Calculations of Power Converter Systems
N. Djekanovic; M. Luo; D. Dujic
2020. PCIM Europe digital days 2020, Online, July, 7-8, 2020.
