ONR, a funding agency within the U.S. Department of Defense,
has awarded this grant to Khanna to encourage collaboration with
the U.S. Navy’s corporate research laboratory, the U.S. Naval
Research Laboratory (NRL).
“We are proud to collaborate with the NRL on a project
critical to both sustainability and national security,” Khanna
said. “Fuel economy and power efficiency translate to
operational flexibility for our military.”
Silicon is the most common component in power devices, but
Khanna’s team will design circuits using instead gallium nitride
to be applied to what’s called direct-current (DC) microgrids
for electric Navy ships. The goal is to help make up to 20
kilovolt gallium nitride (GaN) power electronic devices to
facilitate power distribution.
Khanna said next-generation microgrids, self-contained power
distribution grids that can be on land running off solar and
wind or on an electric navy ship at sea, will benefit from DC
Conventional power distribution grids run off
alternating-current (AC), however, with the advent of newer
circuit materials such as gallium nitride, research suggests
that DC microgrids may be the power architecture of the future.
Gallium nitride technologies have been shown to deliver a
higher performance compared to their silicon-based counterparts,
particularly in DC microgrids, while reducing the energy and
physical space needed to achieve that performance.
“Gallium nitride can operate at much higher voltages,
frequencies and temperatures,” Khanna said.
To be able to realize the high-voltage potential of future DC
microgrid architectures, high-voltage power electronic devices
are needed, such as the devices Khanna is modeling.
Khanna is modeling what the materials would look like and
simulating how they would work, and the Naval Research
Laboratory will take the UToledo models and fabricate the
“Dr. Khanna and his group have been able to develop
experimentally validated simulation models of these important
high voltage GaN devices,” said Dr. Andrew Koehler, electronics
engineer at the Naval Research Laboratory. “Their models allow
them to closely examine the physics that govern the device’s
operation, allowing innovation of new approaches to improve
performance, manufacturability and reliability, which we can
implement into our design and fabrication process.”
The technology is being designed to be used aboard Navy ships
for power generation systems, weapons systems and communications
systems, which can all be electrified.
“We’ll start with a 1-kilovolt device, and gradually move up
to 5, 10 and 15. This will allow us to develop learning cycles
at each incremental voltage, and hopefully the process will get
faster and faster as we fulfill each milestone. By the end of
three years, we hope to have a 20-kilovolt gallium nitride-based
device,” Khanna said.
One 20 kilovolt gallium nitride device can provide power for
at least 20 Tesla car batteries.
Khanna, who focuses his research on next-generation power
electronics, also is using gallium nitride in a NASA-funded
project to improve power for space exploration. He will be
internally collaborating with faculty within the UToledo College
of Engineering who have expertise in materials to help achieve
these objectives for both the U.S. Navy and NASA.
Prior to joining UToledo in 2015, Khanna worked for HRL
Laboratories LLC in California where he was directly involved
with the development of gallium nitride-based battery chargers
for electric vehicles.