The US Department of Energy announced $35 million in awards for 12 projects that find new ways to harness medium-voltage electricity for applications in industry, transportation, on the grid and beyond. The selected projects are part of ARPA-E’s Building Reliable Electronics to Achieve Kilovolt Effective Ratings Safely (BREAKERS) program, as well as the latest OPEN+ cohort, Kilovolt Devices.

The 8 BREAKERS projects will work to develop new direct current (DC) devices to better manage power by eliminating electrical faults, improving efficiency and reaction times, and potentially enabling greater proliferation of energy storage and renewable resources.

The four Kilovolt Devices OPEN+ projects will focus on a variety of challenges facing power electronics in the medium-voltage space, with a particular eye toward grid security and reliability.

Today’s power distribution networks are primarily powered by alternating current (AC) electricity, but DC can provide lower distribution losses and higher power carrying capacity. BREAKERS projects will develop DC devices that prevent electric arcing, a safety hazard, while handling large amounts of power and voltage.

Medium-voltage DC circuit breakers could enable significant improvements in the United States’ electrical system, transforming how electricity is delivered and managed across the entire power grid, as well as critical applications in industry, transportation, and resource production.

BREAKERS projects include:

• Drexel University, Ultra-Efficient Intelligent MVDC Hybrid Circuit Breaker – $4,413,913.
  Drexel University aims to design a significantly more efficient, fast, low-cost, compact, and reliable circuit breaker for medium-voltage direct-current (MVDC) power system. The breaker is designed to protect MVDC systems from electrical faults and expected to respond in 500 microseconds. To realize this goal, Drexel proposes a solid-state circuit breaker based on silicon carbide devices that aims to significantly improve breaker performance for the MVDC ecosystem.

• Eaton Corporation, DC Wide Bandgap Static Circuit Breaker – $3,760,000.
  Eaton will develop a silicon carbide-based direct-current circuit breaker design that boosts efficiency and can scale up or down medium voltage application requirements. The team’s comprehensive approach includes a robust design that effectively dissipates excess energy and autonomously coordinates fault protection across multiple devices. The project results will extend to future ultra-wide bandgap power semiconductor devices and other advances affecting future generations of devices and power electronics.

• Eaton Corporation, Ultra-Efficient Intelligent MVDC Hybrid Circuit Breaker – $4,413,913.
  Eaton will build an ultra-high efficiency, medium-voltage direct-current (MVDC), electro-mechanical/solid-state hybrid circuit breaker prototype, combining the advantages of both breaker types in offering low conduction losses and fast response times. The team will develop a high-speed actuator/vacuum switch to carry the normal electrical load. Combined with a novel transient commutation current injector, this switch will transfer power to a separate solid-state device, interrupting the current in event of a fault. The design should allow for scaling in voltage and current, enabling a range of circuit breakers across the MV application space.

• GE Global Research, Inline Gas Discharge Tube Breaker for Meshed MVDC Grids – $4,350,686.
  GE Global Research will develop a medium-voltage direct-current (MVDC) circuit breaker with exceptionally fast response time based on its innovative gas tube technology. Gas tubes switch without mechanical motion by transitioning the internal gas between its ordinary insulating state and a highly conductive gas plasma. The team will develop a new cathode and control grid to reduce power loss during normal operation and meet program performance and efficiency targets. A fast MVDC breaker is an important component to enable uprating existing alternating-current distribution corridors in congested urban areas to MVDC, and connect distributed renewable energy sources to concentrated demand for growing applications such as electric vehicle charging.

• Georgia Tech Research Corporation, EDISON – Efficient DC Interrupter with Surge Protection – $3,000,000.
  Georgia Tech is proposing a novel hybrid direct-current (DC) circuit breaker technology that will enable multi- terminal DC power systems. The breaker’s mechanical switch enables switching speeds 10 times faster than the existing technology, severing the mechanical linkage while the power-electronics-based circuit handles the fault current. A new configuration of the fast switch and solid-state devices/circuits will reduce steady-state losses compared to state-of-the-art hybrid circuit breakers. A new control scheme dramatically reduces the peak fault current levels, enabling more compact packaging and increasing reliability. A consortium of industry partners will guide the design process and advise on commercialization.

• Marquette University, Ultra-Fast Resonant DC Breaker – $500,000.
  Marquette University will develop a direct-current (DC) breaker combining the advantages of a vacuum interrupter with a wide-bandgap based resonant current source and novel actuator topology. The proposed solution represents a transformational state-of-the-art DC breaker scalable across voltage and current in medium voltage DC applications, such as power distribution, solar, wind, and electric vehicles.

• The Ohio State University, T-Type Modular DC Circuit Breaker (T-Breaker) for Future DC Networks – $2,309,950.
  The Ohio State University will develop a medium-voltage direct-current (MVDC) circuit breaker prototype based on a modular design using silicon carbide modules to reduce cost and weight while enabling simpler manufacturing, increased reliability, functionality, efficiency, and power density. The modular structure will be self-sustaining and allow for inherent scalability while providing possibilities for multiple ancillary functions.

• Sandia National Laboratories, ARC-SAFE: Accelerated Response semiconducting Contactors and Surge Attenuation for DC Electrical systems – $2,250,000.
  Sandia National Laboratories will develop a solid-state circuit breaker for medium-to-high voltage applications using switches based on the wide-bandgap semiconductors silicon carbide (SiC) and gallium nitride (GaN). The concept builds on Sandia’s knowledge of optically triggered GaN devices, as well as the team’s experience in circuit design for medium-voltage (MV) applications. Sandia will build a prototype breaker to demonstrate a fast response time using a photoconductive switch that is potentially scalable from 1 to 100 kV for direct-current (DC) systems. This technology could contribute to more widespread adoption of MVDC power distribution across the grid.

The OPEN+ Kilovolt Devices selections are:

• GE Global Research, Advanced Medium Voltage SiC-SJ FETs with Ultra-Low On-Resistance – $3,090,746.
  GE Global Research will develop a device architecture for the world’s first high-voltage silicon carbide (SiC) super junction (SJ) field-effect transistors. These devices will provide highly efficient power conversion (such as from direct to alternating current) in medium voltage applications, including renewables like solar and wind power, as well as transportation. The transistors will scale to high voltage while offering up to 10 times lower losses compared to commercial silicon-based transistors available today.

• The Ohio State University, GaN MOCVD Growth on Native Substrates for High Voltage (15-20 kV) Vertical Power Devices – $2,211,712.
  The Ohio State University will develop gallium nitride (GaN) semiconductor materials suitable for high voltage (15-20 kV) power control and conversion. The team will develop a unique method to grow thick GaN films with low background impurity contamination, necessary to allow high voltage operation with high efficiency. The thick GaN layers will be deposited on high-quality bulk GaN base materials with reduced defects, critical to depositing high-quality GaN films on top, and perform high-voltage device design, fabrication, and testing to provide feedback for further GaN material growth and optimization.

• Sandia National Laboratories, 20 kV Gallium Nitride pn Diode Electro-Magnetic Pulse Arrestor for Grid Reliability – $5,415,000.
  Sandia National Laboratories will develop a new device to prevent damage to the power grid caused by electromagnetic pulse (EMP). The EMP arrestor will comprise diodes fabricated from the semiconductor gallium nitride (GaN), capable of responding on the nanosecond timescale required to protect the grid against EMP threats. The arrestor will be capable of blocking 20 kilovolts (kV), enabling a single device to protect distribution-level equipment on the grid. The team will focus on GaN crystal growth and device design to achieve the 20 kV performance target. In addition, the team will create a pilot production line to serve as a model for eventual commercial production.

• Virginia Tech, 20-kV GaN Switch Technology Demonstrated in High-Efficiency Medium-Voltage Building Block – $3,000,000.
  Virginia Tech will accelerate deployment of power electronics into grid-scale energy applications by developing 20 kV gallium nitride devices integrated into a medium-voltage power module. For the GaN power devices, high quality substrates and innovative growth techniques will be used to reduce the background impurity contamination in the thick layers needed to block 20 kV. The power module will be fabricated using three- dimensional (3D) packaging for improved thermal management and high power density at 20 kV. The power module will enable the full potential of high-voltage, high-temperature, and fast-switching GaN devices in medium-voltage power converters for use in renewable energy grid-level applications and transportation.