ARC-SAFE: Accelerated Response semiconducting Contactors and Surge Attenuation For DC Electrical systems
Sandia National Laboratories will develop a solid-state circuit breaker for medium to high voltage applications based on a gallium nitride (GaN) optically triggered, photoconductive semiconductor switch (PCSS). During normal operation, the current will flow through high-performance commercial silicon carbide (SiC) devices to achieve high efficiency. When a fault occurs, the fast-response GaN PCSS will be used to break the current. The concept builds on Sandia’s knowledge of optically triggered GaN devices, as well as the team’s experience in circuit design for MV applications. The GaN PCSS will enable high-voltage operation, potentially scalable from 1 to 100 kV, while achieving superior electrical isolation due to the optical triggering approach. This technology could contribute to more widespread adoption of MVDC power distribution across the grid.
The proposed breaker is installed close to loads to rapidly detect and react to the short-circuit fault. Thus, it could enable an increased number of electronic loads that operate using DC, such as ultra-fast electric vehicle charging stations and utility scale energy storage battery units, to connect to the MV distribution grid. This would improve overall power delivery efficiency.
MVDC breaker-enabled microgrids could facilitate greater deployment and adoption of distributed renewable resources, greatly reducing power sector emissions. Electrification of transportation (e.g., ships, aviation) with DC systems would also reduce emissions.
Proliferation of MVDC systems protected by more effective DC circuit breakers could drive higher energy efficiency, lower equipment costs, and bolster grid resiliency.