Despite recent advances, there remains a significant technology gap in the safety and protections mechanisms required to mitigate potentially damaging faults in those systems. HMNTL's Can Bayram has a new collaborative project that will help address these difficulties.
Recent advances in hardware for handling direct current (DC) electricity have created an opportunity to greatly improve the efficiency, security, and safety of the U.S. power system, while supporting new industries and grid design options. According to HMNTL Associate Professor Can Bayram, there remains a significant technology gap in the safety and protections mechanisms required to mitigate potentially damaging faults in those systems. His work with the Sandia National Laboratories on the ARC-SAFE (Accelerated Response semiconducting Contactors and Surge Attenuation For DC Electrical systems) project will help address these difficulties.
“DC power brings a strong set of attributes for today's evolving grid and beyond,
including lower distribution losses and higher power carrying capacity,” says Bayram, an ECE Associate Professor. “It’s extremely useful in industrial applications, electrified transportation, and resource production including offshore oil, gas, and wind power.”
Despite these advantages, today’s power grid is primarily powered by alternating current (AC) electricity as the risk of electrical fault (shorts, overloads, etc.) remains an important hurdle that prevents the increased use of DC power.
“In AC networks, electricity alternates direction periodically, naturally providing a ‘zero crossing’ where no current flows for a brief moment,” says Bayram. “This allows electrical faults to easily be extinguished.”
DC networks deliver power without these zero crossings which greatly increases the likelihood of electrical arcs (an electrical breakdown of a gas that creates a prolonged electrical discharge that could potentially cause injuries through burns or fire).
“Project teams will either develop transformational improvements to conventional DC circuit breakers or construct circuit breakers based on completely novel designs,” says Bayram. “Combined with recent advances in wide band-gap semiconductors, voltage source converters, and DC-to-DC converters, there is a significant opportunity to enable greater use of DC across many important applications.”
The projects that comprise ARPA-E's BREAKERS (Building Reliable Electronics to Achieve Kilovolt Effective Ratings Safely) program will develop novel technologies for medium voltage direct current (MVDC) circuit breakers.
“BREAKERS projects will need to overcome current limitations while supporting greater power and voltage ratings than traditional low voltage solutions,” says Bayram. “Ultimately, innovations in MVDC circuit breakers could enable significant efficiency improvements in the United States, transforming how electricity is delivered and managed across the entire power grid, in transportation, and other valuable parts of the economy.”
DC microgrids could also mean greater deployment and adoption of renewable energy sources. Electrification of transportation such as ships and planes with DC power systems would also significantly reduce damaging emissions.