Description: SET Group will design, build and qualify a Gallium Nitride (GaN) based High Power High Frequency Wide Range LLC Resonant Converter capable of handling high power and high frequency operation. The GaN LLC Converter will operate at 1 MHz with an input voltage of 95V - 160V and output of 600V - 2kV, capable of handling up to 5 kW. Current technology utilizes silicon-based solutions for power conversion and distribution. GaN can fundamentally perform well beyond current silicon based hardware. GaN has direct benefits such as higher power density, reduced footprint, increased power capacity, and improved power efficiency. Increasing frequency of operation results in smaller components but it also creates a challenge for thermal management and magnetic component design. SET Group will develop a novel thermal management system utilizing additive manufacturing which will consolidate the housing and cooling in a single part. Similarly, SET Group will design a novel transformer that will integrate the resonant inductor, transformer, and output voltage multiplier stage into a single unit. SET Group's goal of integration is to reduce the number of parts to decrease size of unit, mass and volume. This results in higher power density, lower manufacturing costs and higher reliability. SET Group will design the GaN-LLC Converter to be used for Solar Electric Propulsion (SEP), but the outcome of this work will serve as a platform for other power conversion products utilizing GaN technology to be developed.

Benefits: The greatest advantage of the technology proposed by SET Group is its ability to be used across a wide range of applications. An immediate application of our technology is for NASA's Solar Electric Propulsion systems. The PPUs in their system convert the 300V solar array output to the 700V - 2000V input level of an electric thruster. The proposed Wide Range GaN LLC Power Converter is a great candidate for that mission. In addition, the proposed work will serve as a platform to demonstrate GaN-based power conversion technology as a viable and better alternative than the current Si-based power conversion products.

Demand for broadband internet access in remote areas, airplanes and higher data capability (i.e. 4K TV, 360o video, etc), have pushed satellite manufacturers to provide more powerful RF transponders. These transponders require higher power, increasing satellite size and launching costs, which results in more expensive satellite services for end consumers. SET Group's proposed GaN-LLC can provide satellite manufacturers a competitive edge by increasing power capabilities while reducing size, weight, and cost. In recent years, GEO satellite service providers, such as DirecTV, have been requesting more powerful satellites to handle the wider bandwidth needed to keep up with the data demand (DirecTV now offers 4K video). To meet broadband internet demand, companies have turned to LEO satellites, which due to their closer proximity to Earth, have a lower delay of signal (latency) over a GEO satellite. This is important for broadband internet given it is a two-way communication. Oneweb, a satellite manufacturer startup, will provide developing countries affordable access to internet by deploying a large constellation of LEO satellites (750 satellites) by 2020. SpaceX has also announced their own 4000 LEO satellite constellation. These satellites are small, thus reducing launching costs. A GaN-based EPS and PPU fits the equivalent capabilities of a much larger satellite into a much smaller and cost-effective one.