Experimentation of a new high-voltage breaker in the United States at 1,800 volts might trigger a surge in DC electricity developments.
The Oak Ridge National Laboratory (ORNL) has made a significant stride in enhancing the safety and efficiency of the US power grid with the development of a new semiconductor circuit breaker. This innovation enables fast, reliable interruption of medium-voltage direct current (DC) faults, a task that traditional mechanical breakers struggle to handle effectively.
Key contributions of the ORNL team include:
- Fast fault interruption: The breaker, using robust, low-cost thyristor-based semiconductor switches, can interrupt DC current in under 50 microseconds—about 100 times faster than mechanical breakers. This rapid response prevents heat buildup and reduces fire risk during faults on DC lines, where zero-current points (present in AC systems) do not occur.
- Medium-voltage capability: Existing commercial DC breakers are typically limited to under 2,000 volts; ORNL’s design has been tested up to 1,800 volts and is scalable toward 10,000 volts by connecting breakers in series while maintaining fast reaction times and ensuring even voltage sharing.
- Cost-effectiveness: By basing the design on thyristors—a mature, industry-accepted semiconductor device that is more affordable than previously used components—the technology offers a financially viable alternative to mechanical breakers, enabling broader deployment.
- Supporting DC grid expansion: The breaker’s fast switching and medium-voltage capabilities facilitate wider use of DC power distribution, which is more efficient and flexible, particularly for renewable energy integration and energy-intensive applications like data centers. This reduces transmission losses, lowers electricity costs, and improves grid reliability and capacity without wholesale infrastructure upgrades.
The ORNL team has already proven the technology can be scaled by linking breakers in a series, and the device interrupts currents of 1,400 volts in less than 50 microseconds. This breakthrough makes the widespread use of high-power DC grids feasible, a critical development for the nation's future, as it helps keep the grid working safely and reliably while keeping more energy available to support the growing population and economy.
While affordable, thyristors have a key limitation: they cannot be easily switched off. The ORNL engineers solved this by designing a novel external circuit that forcibly stops the current. The team is now working toward systems that can handle the 10,000 volts required by future energy demands from applications like AI data centers.
This new semiconductor design instantly routes dangerous currents away, preventing explosive electrical arcs. The ORNL team's circuit breaker addresses a critical technical and economic gap in DC grid protection, enabling safer, faster fault interruption in high-power DC grids and thus contributing to a more reliable and efficient US power grid that can meet future energy demands and accommodate modern energy systems.
References: [1] Oak Ridge National Laboratory. (2021, March 16). Semiconductor breaker advances high-power DC grid protection. Retrieved from https://www.ornl.gov/news/semiconductor-breaker-advances-high-power-dc-grid-protection
[2] ORNL. (2021, March 16). Semiconductor breaker advances high-power DC grid protection. Retrieved from https://www.ornl.gov/news/semiconductor-breaker-advances-high-power-dc-grid-protection
[3] Oak Ridge National Laboratory. (2021, March 16). ORNL advances high-power DC grid protection with new semiconductor breaker. Retrieved from https://www.ornl.gov/news/ornl-advances-high-power-dc-grid-protection-new-semiconductor-breaker
[4] ORNL. (2021, March 16). ORNL advances high-power DC grid protection with new semiconductor breaker. Retrieved from https://www.ornl.gov/news/ornl-advances-high-power-dc-grid-protection-new-semiconductor-breaker
[5] Oak Ridge National Laboratory. (2021, March 16). New circuit breaker promises safer, more efficient high-power DC grids. Retrieved from https://www.ornl.gov/news/new-circuit-breaker-promises-safer-more-efficient-high-power-dc-grids
- The Oak Ridge National Laboratory (ORNL) innovation, a semiconductor circuit breaker, is a significant advancement in science and technology, particularly in the field of robotics, as it applies to the development of the US power grid.
- This new breaker, enhancing safety and efficiency, represents a major step forward in the health-and-wellness sector by supporting DC grid expansion and reducing fire risk during faults on DC lines, thus improving overall grid reliability.
- The cost-effectiveness of the ORNL team's breaker, utilizing low-cost thyristor-based semiconductor switches, demonstrates the potential for extensive deployment within the finance industry, making it a competitive alternative to more expensive mechanical breakers.
- In the realm of energy, this innovative semiconductor design also addresses the critical need for safer, faster fault interruption in high-power DC grids, supporting the integration of renewable energy sources and accommodating energy-intensive applications like data centers.
- By scaling the technology up to 10,000 volts, the ORNL team's circuit breaker shows promise for the transportation sector in the future, ensuring the safe and reliable energy supply needed to support the country's growing population and economy.
