Yuhao Zhang receives NSF CAREER award to develop new generation of power devices for electric vehicles, data centers, and renewable energy processing
Yuhao Zhang, assistant professor at the Center for Power Electronics Systems (CPES) in the Bradley Department of Electrical and Computer Engineering, has received a National Science Foundation CAREER Award to develop a new generation of medium-voltage power devices that will enable advancement in the performance, frequency, efficiency, and form factor of the power electronic systems in electric vehicles, among other applications.
“Currently, many medium-voltage power electronics systems provide only about 70 percent efficiency; 30 percent of energy is lost in power conversion,” Zhang said. “By monolithically integrating a power device and an integrated circuit into the same chip, we will be able to significantly increase efficiency.”
Zhang’s research is particularly timely in support of an auto industry striving to meet the challenges of climate change. In August, President Joe Biden signed an executive order to encourage more sales of electric cars, and some automakers announced their shared aspiration to achieve sales of 40 to 50 percent of annual U.S. volumes of electric vehicles (battery electric, fuel cell and plug-in hybrid vehicles) by 2030 in order to move the nation closer to a zero-emissions future consistent with Paris climate goals.
As consumers move to electric cars, the demand for smaller, lighter-weight, and higher-efficiency powertrain systems will increase, Zhang said, and these new powertrain systems will make improved energy efficiency possible in electric vehicles. Zhang estimates that the power devices he is developing can ultimately enable a significantly higher range in electric cars like the Tesla.
“We also believe that we can increase performance at a lower cost - a benefit to automakers and, ultimately, the consumer,” Zhang said.
From an academic perspective, the interdisciplinary nature of this project allows significant intellectual merits in materials, devices, processing technologies, and power modules, he said.
Data centers in Google, Facebook, and Amazon as well as other entities like solar and wind power plants that rely on how electricity is converted will also benefit from these new power electronic devices.
To create a new generation of medium-voltage power devices, Zhang and his team will focus on understanding the fundamental leakage current and breakdown physics in vertical gallium nitride devices on silicon substrates; probe new device designs and functional structures for vertical and lateral gallium nitride FinFETs; develop innovative epitaxial structure and processing technologies for monolithic integration; and explore advanced device simulation and modeling that account for material non-idealities (defects and traps) and circuit dynamics.
The CAREER award is the National Science Foundation’s most prestigious award for early-career faculty with the potential to serve as academic role models in research and education, and to lead advances in the mission of their organization, as stated by NSF.
CAREER awardees are also required to find ways to integrate education and research and to conduct outreach.
To address these components, Zhang is establishing a unique research program in collaboration with the Major Design Experience program that will train undergraduate students in technical, research, and professional skills and allow them the opportunity to tackle interdisciplinary problems in the fields of materials, devices, and power electronics.
“Mentoring is an important part of the program,” he said. “Leveraging the substantial resources at the Center for Power Electronics Systems, we will facilitate student interactions with our collaborators in the power semiconductor industries.”
Results of Zhang’s research will also be integrated into graduate level-course curriculum. “One of our goals is to develop and promote power semiconductor education materials to help maintain the U. S. power semiconductor workforce,” he said.
Outreach efforts will also include involvement in pre-college summer camps and provide summer research opportunities to K-12 students and teachers that encourage their participation in microelectronics and power electronics research.
“In all of these undertakings, we are putting particular emphasis on advising under-represented and minority students,” Zhang said.
Written by Barbara L. Micale