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A Multiport DC Transformer to Enable Flexible Scalable DC as a Service

Conference · · IEEE Energy Conversion Congress and Exposition (ECCE)

The rapid adoption of new DC loads and sources, including photovoltaic arrays, DC fast charging of electric vehicle, battery energy storage and data centers, requires a large amount of DC power conversion. A majority of new deployments also necessitate the integration of multiple DC loads and sources at one site. The traditional approach to serve these new applications relies on multiple standard power converters, each dedicated to a source or load, and results in highly customized systems, with challenging control coordination, complex protection strategies, and poor scalability. Instead, this paper proposes the concept of a multiport DC transformer (MDCT) as a modular building block for realizing a flexible, scalable DC as a Service system and address this rapidly growing need. The MDCT uses the S4T to achieve very tight control of cycle-by-cycle energy exchange between multiple ports, with high efficiency. A single multiport converter replaces 4-6 distinct converters, integrates all energy flows and manages protection. As a result, a new layered control architecture is introduced to ensure stability and scalability of the MDCT, with multiple S4T power converter building blocks connected in parallel to realize a fully modular system and reach the target power levels.

Research Organization:
Georgia Institute of Technology, Atlanta, GA (United States)
Sponsoring Organization:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Renewable Power Office. Solar Energy Technologies Office
DOE Contract Number:
EE0008351
OSTI ID:
1923321
Journal Information:
IEEE Energy Conversion Congress and Exposition (ECCE), Vol. 2021; Conference: 2021 IEEE Energy Conversion Congress and Exposition (ECCE), Vancouver, BC (Canada), 10-14 Oct 2021; ISSN 2329-3721
Publisher:
IEEE
Country of Publication:
United States
Language:
English

References (7)

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