Grid

Switched Source will develop a power-electronics based hardware solution to fortify electric distribution systems, with the goal of delivering cost-effective infrastructure retrofits to match rapid advancements in energy generation and consumption. The company’s power flow controller will improve capabilities for routing electricity between neighboring distribution circuit feeders, so that grid operators can utilize the system as a more secure, reliable, and efficient networked platform.

Illinois Institute of Technology (IIT) will develop autonomously operated, programmable, and intelligent bidirectional solid-state circuit breakers (SSCB) using transistors based on gallium nitride (GaN). Renewable power sources and other distributed energy resources feed electricity to the utility grid through interfacing power electronic converters, but the power converters cannot withstand a fault condition (abnormal electric current) for more than a few microseconds.

Georgia Tech Research Corporation and its project team will develop a solid-state transformer for medium-voltage grid applications using silicon carbide with a focus on compact size and high-performance. Traditional grid connected transformers have been used for over 100 years to 'step down' higher voltage to lower voltage. Higher voltages allows for delivery of power over longer distances and lower voltages keeps consumers safe. But traditional distribution transformers lack integrated sensing, communications, and controls.

Opcondys will develop a high-voltage power converter design for energy storage systems connected directly to the power grid. Opcondys' converter design will use a modified switched multiplier topology that will allow connection to utility transmission lines without intervening step-up transformers. It uses a photonic, wide bandgap power switching device called the Optical Transconductance Varistor. This is a fast, high-voltage, bidirectional device which reduces the number of circuit elements required for charging and discharging the storage element.

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 Ohio State University (OSU) team will develop a MVDC circuit breaker prototype based on its novel “T-breaker” topology. OSU will leverage its unique high voltage and real-time simulation facilities, circuit prototyping experience with MV silicon carbide devices, and capability in developing protection strategies for faults in DC networks. The result will be a circuit breaker with reduced cost and weight, simplified manufacturing, and increased reliability, functionality, efficiency, and power density.

Georgia Tech is developing a novel hybrid direct current (DC) circuit breaker that could enable multi-terminal DC power systems. The breaker’s mechanical switch enables switching speeds 10 times faster than 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.

GE Research will develop a medium voltage direct current (MVDC) circuit breaker using gas discharge tubes (GDTs) with exceptionally fast response time. GDTs switch using no mechanical motion by transitioning the internal gas between its ordinary insulating state and a highly conductive plasma state. The team will develop a new cathode and control grid to reduce power loss during normal operation and meet program performance and efficiency targets.

Eaton will build an ultra-high efficiency, medium voltage direct current (MVDC), electro-mechanical/solid-state hybrid circuit breaker (HCB) that offers both low conduction losses and fast response times. The team will also develop a high-speed actuator/vacuum switch (HSVS) combined with a novel transient commutation current injector (TCCI). This switch will transfer power to a separate solid-state device, interrupting the current in the 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.

Drexel University is proposing a solid-state MV circuit breaker based on silicon carbide devices, a resonant topology, and capacitive wireless power transfer that aims to significantly improve breaker performance for the MVDC ecosystem. The project combines innovations in using an active resonant circuit to realize zero-current switching, wireless capacitive coupling between the conduction and breaker branches to avoid direct metal-to-metal contact for rapid response speed, and wireless powering to drive the MV switches for improved system reliability.