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DOE OSTI · 2371492

Intelligent, grid-friendly, modular extreme fast charging system with solid-state DC protection

Lukic, Srdjan
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Abstract

The development of electric vehicle (EV) charging infrastructure is crucial for the widespread adoption of electric transportation. However, implementing such infrastructure is a complex task that requires consideration of factors such as space limitations, adherence to industry standards, grid capacity, and other technical and policy issues. This project seeks to create a framework for the efficient design of compact medium voltage (MV) extreme fast charging (XFC) stations for EVs. The station design involves the use of a solid-state transformer (SST) that connects to the MV distribution network, delivering power to a shared DC bus. This innovative approach eliminates the need for a step-down transformer to provide low-voltage service by connecting directly to the MV distribution network. Eliminating the low-frequency transformer not only reduces the system footprint and losses but also eliminates inrush currents during grid black-start. Additionally, placing power electronics directly on the distribution system allows for high-bandwidth filtering and power factor correction. The inclusion of a shared DC bus enables multiple charging dispensers and DC storage/generation units to connect, forming a DC microgrid. This setup facilitates power sharing with minimal conversion stages. The project showcases a DC distribution network protected by intelligent solid-state (SS) DC circuit breakers (DCCB) capable of isolating the smallest section of the faulted circuit much faster than existing mechanical solutions.

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24 POWER TRANSMISSION AND DISTRIBUTION25 ENERGY STORAGE29 ENERGY PLANNING, POLICY, AND ECONOMY32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION42 ENGINEERING47 OTHER INSTRUMENTATIONElectric Vehicle Chargers

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Lukic, Srdjan. 2024-06-10. Intelligent, grid-friendly, modular extreme fast charging system with solid-state DC protection. https://doi.org/10.2172/2371492

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