UA professor Yue Zhao receives $3.4 million for solar inverter research

Yue Zhao, assistant professor of electrical engineering at the University of Arkansas, has received $3.4 million to continue to develop a high-density, 300-kilowatt, silicon-carbide solar inverter. On Monday (Aug. 20), the UA announced the award of which nearly $2.77 million was provided by the U.S. Department of Energy Solar Energy Technologies Office, and the remaining $713,853 was matching funds from the university and industry partners.

“Working with cutting-edge, silicon-carbide power electronics, our research team uses a holistic design approach to develop a solar inverter that will achieve higher efficiency and power density, an extended service life and lower long-term costs,” Zhao said.

Solar power arrays produce direct current, or DC, and solar inverters convert DC into alternating current, or AC, which is the type of power delivered to the grid. Existing systems use bulky step-up transformers that increase the AC voltage before transferring it to the grid.

Zhao’s solar inverter design would eliminate the need for step-up transformers as it would generate AC at the voltage needed to be transferred directly to the grid. Compared to existing systems, the inverter would have a greater power density, be smaller and reduce maintenance and installation costs.

By 2030, the U.S. Department of Energy expects to reduce the cost of solar electricity by 50%, and Zhao looks to use his research to develop a commercial-scale, silicon-carbide solar inverter system. If he’s successful, the power density of the inverter would be 10 times greater and would cost 50% less than existing technology.

Zhao was selected as a part of the Advanced Power Electronics Design for Solar Applications funding program of the Solar Energy Technologies Office. The program is focused on developing new technology to improve devices that serve as an interface between solar photovoltaic arrays and the electric power grid. The devices are expected to enhance the reliability and resilience of the U.S. power grid.

Zhao’s team is developing the solar inverter at the UA’s National Center for Reliable Electric Power Transmission, a 6-megawatt electronics testing facility at the Arkansas Research and Technology Park in Fayetteville. Researchers at the center work with silicon carbide, a semiconductor material, to build power electronic devices.

“We are very fortunate to have built a strong power electronics program with the support of (UA) administration,” Zhao said. “This award reflects the competitiveness of our program and the great team we have been able to assemble.”

The team includes Juan Balda, electrical engineering professor; Alan Mantooth, electrical engineering distinguished professor; and David Huitink, mechanical engineering assistant professor. Industry partners include Cree Fayetteville, Eaton Corp., and NextWatt LLC.