Hometown: Panchkula, Haryana, India
Graduation date: Spring 2023
MORE | Spring 2022
Multi-Constraint Optimization and Co-Design of a 2-MHz All-GaN based 1kW 96% Efficient LLC Converter
With the objective of minimizing the power losses in a 2 MHz LLC resonant converter, a novel multi-variable multi-constraint design optimization algorithm is developed and analyzed in this manuscript. Intricately curated constraints and corresponding design-based trade-offs are explained for a complete co-design of a multi-MHz resonant converter that result in an efficiency enhancement of 3.46%, compared to relevant state-of-the-art. In addition, the paper focuses on accurate characterization and parametric minimization of the AC resistance by optimal selection of transformer winding configuration, while achieving a controllable leakage flux for the resonant inductor integration into the high frequency planar transformer (HFPT) thereby reducing the effective winding losses by 6%. Further, the proposed optimization algorithm is experimentally verified by developing an all-GaN based LLC converter rated at 1kW, designed at 2 MHz resonant frequency. While achieving a power density of 6.2 W/cm3, the efficiency at 20% load is experimentally reported to be 92%, while the peak efficiency is estimated to be 96.08%.
Mentor: Ayan Mallik
Featured project | Spring 2022
Nitish Jolly is an electrical engineering graduate student designing dense, energy-efficient power converters for data centers with Assistant Professor Ayan Mallik. His MORE research project was also sponsored by W. L. Gore & Associates, which provided an additional $500 in project support.
How will your research project impact the world?
Considerably large loads of approximately 7 kilowatts and less space in data centers challenge the thermal stability and power density of power converters. The proposed power electronics topology in my project reduces the overall size of loads by 50% and enhances efficiency by around 8% over conventional designs. The amount of energy saved due to potential efficiency enhancements and size reduction of this unit can be equivalently mapped into powering 10 8W rack cooling systems or reducing the size to half of a smartphone.
What has been your most memorable experience as a student researcher in MORE? Did you have a particular “aha!” moment during your project?
My most memorable experience in this program was building the proof-of-concept for my research project. After multiple failures, when the hardware worked as estimated, that was my “aha!” moment.
Have there been any surprises in your research?
Yes, there have been plenty of surprises during the course of my research. One of which was the gallium nitride (GaN)-based devices used in my DC to DC power converter exploding. I discovered this was due to the lesser explored science behind circuit parasitics at a very high switching frequency.
How do you see this experience helping with your advanced degree goals?
MORE definitely provided me with an excellent opportunity, ample motivation and a key launchpad to advance my research as well as pursue a doctoral program after completing my master’s degree.
Why should other students get involved in this program?
Other students should get involved in MORE because it is an excellent platform to advance your research, enhance engineering and technical graduate curriculum by providing hands-on lab experience, faculty mentorship and also provides financial support for your research project.
Sponsored project | Spring 2022
W. L. Gore & Associates is a uniquely creative, product leadership enterprise that has served a variety of global markets for 60 years, and provides innovative solutions that its associates stand behind. Gore established funds to support undergraduate students in the Fulton Undergraduate Research Initiative program and graduate students in the Master’s Opportunity for Research in Engineering program, and values student-driven research and developing relationships with students in the programs.