A UT Dallas researcher is advancing what he calls “a transformational paradigm for power management and delivery” that could significantly reduce energy consumption in battery-operated portable devices, LED lighting systems and other products.
His approach would shift power management in many cases from bulky power adaptors to tiny semiconductors, not only increasing the efficiency of power conversion but also eliminating the cost of the materials needed for external adaptors.
Regarding increasingly popular LED lighting systems alone, Dr. Hoi Lee estimates that in the United States his approach could save energy on the order of a few dozen terawatt hours a year, which is the equivalent of several power plants’ worth of electricity output.
The National Science Foundation has awarded Lee $400,000 through its Faculty Early Career Development Awards program to pursue the work. The program recognizes junior faculty who are considered likely to become leaders in their field, and this is the fifth such award received by UT Dallas engineering and computer science faculty in the past three years.
“Hoi Lee has been instrumental in advancing power management circuit design for mobile platforms, something critical in today’s wireless mobile computing and mobile information access world,” said Dr. John Hansen, head of electrical engineering at the University’s Erik Jonsson School of Engineering and Computer Science and holder of the Distinguished Chair in Telecommunications Engineering. “Basically, advancements in mobile technology for information access and computing are worthless unless you have sufficient power to sustain your devices.”
Added Lee: “The energy saving could decrease both imports of energy and the harmful carbon-equivalent emissions, while the material saving through miniaturization could lead to significant cost reductions that would promote the country’s technological leadership.”
From a technical standpoint, his research involves using tiny capacitors instead of bulky transformers in power converters.
“Capacitors are much smaller and cheaper than the inductors and transformers being used today,” Lee said. “One of the interesting research tasks is to use capacitors to achieve galvanic isolation that is only realized by bulky transformers today. This can improve the power density of the power converters by orders of magnitude, and high power density is particularly important in mobile devices, where space is limited.”
Lee received his PhD in electrical and electronic engineering from the Hong Kong University of Science and Technology in 2004.
He directs the Mixed-Signal and Power Integrated Circuit Group, and his research interests include power-management circuits for portable, energy harvesting, solid-state lighting and biomedical implant applications; integrated bioelectronics for cochlear and neural prostheses; and low-voltage low-power analog and mixed-signal circuit techniques. His research has been sponsored by the U.S. Department of Energy, the National Institutes of Health, Texas Instruments and others.