Power converters are an essential component of many electrical systems, from a smartphone or electric car to the electric grid. These devices flip current from AC to DC or DC to AC, modulate electric frequency, stabilize voltages, and generally make sure electricity is in a form usable by our electronics.
Mahima Gupta
One of the problems is, the capacitors in the analog versions of these essential components are quite bulky, sometimes taking up 40 to 50 percent of the converter volume. That’s why Mahima Gupta, who joined the University of Wisconsin-Madison Department of Electrical and Computer Engineering as an assistant professor in June 2024, is designing new types of small, high-density semiconductor-based power converters to more efficiently power the next generation of electric devices. Ranging from just a few kilowatts to many megawatts, the new converters could accelerate integration of solar and wind farms, microgrids, electric cars and other electrified transportation systems.
“My work is mostly theoretical devising new converter circuits and using advanced modeling approaches, asking what can be done to make power converters really, really small and efficient,” she says. “I also work in integration of power semiconductor devices into circuits and look at the modulation and control for new circuit topologies. I’ve also been doing research in overcoming the challenges of wide bandgap devices due to high electromagnetic noise at the noise source which is the device itself.”
During her sophomore year as an undergraduate at the Birla Institute of Technology and Science-Pilani in India, Gupta signed on for a three-month internship at a nuclear power plant. There, with the help of a mentor, she explored the plant’s incredibly complex electrical system, with layers of backups, generators and transformers. “Seeing the vastness and the scale of the systems was quite motivating,” she says.
She dedicated the rest of her undergraduate career to power systems, electrical machines and power electronics. That interest led her to UW-Madison and the Wisconsin Electric Machines and Power Electronics Consortium (WEMPEC) research group for her graduate work. At UW-Madison, advised by ECE Professor and WEMPEC Director Giri Venkataramanan, Gupta began her research into power converters.
After earning her PhD, she spent a year at Ford Motor Company, working on electric vehicles as part of the research and advanced engineering group, designing electrified powertrain systems. In 2020, Gupta joined Portland State University in Oregon as an assistant professor.
UW-Madison, Gupta says, is an ideal place to pursue her research. As the world electrifies, there’s a need for power converters that can operate at the gigawatt level. “With the development of clean energy solutions and the integration of renewable energy applications, there are lots of interesting design challenges coming up for the power electronics community,” she says. “What I’m hoping to do at UW-Madison is to look more holistically at addressing the challenges of power electronics, from materials and devices to packaging, thermals, layout circuits, control systems, computing and systems. More like a full-stack approach.”
Madison, she says, has the facilities, resources and researchers to support this type of full-stack research. “Obviously, not one person can do this all. Collaboration is the key to what I’m envisioning, and there is an excellent group of researchers at UW-Madison,” she says. “I’m very excited and look forward to the next steps in collaborative research.”
Gupta also says the university’s industry connections and the Wisconsin Alumni Research Foundation, which helps patent and commercialize innovations, will aid in growing her research.
PhD student Araz Saleki also will be joining Gupta at UW-Madison. Saleki is working on a National Science Foundation-funded project to design very-high-density and efficient power converters for integration of battery energy storage systems into the electric grid.
Gupta says she’s happy to return to Madison, where she spent six years pursuing her PhD. “I’m not looking forward to the cold,” she says. “But I love Madison. The ability to do cross-cutting research is what appeals to me most, along with the community at work and otherwise.”