Advanced Electromagnetic Analysis and High-frequency Impedance Design for Magnetic Ferrite Inductors and Transformers

University Of Florida, Gainesville FL

Investigators

Abstract

Electromagnetic interference (EMI) generated by modern power conversion circuits is an electromagnetic (EM) pollution to all electronic circuits and equipment. Wide bandgap (WBG) devices are high-speed semiconductor devices that can reduce energy loss, cost, and size of the power conversion circuits, so they are deemed promising to replace conventional Si devices in power conversion circuits. However, their high speeds lead to higher EMI than conventional Si devices, which slows down the wide adoption of WBG devices in the power conversion industry. Magnetic components including inductors and transformers play a big role in the generation and reduction of EMI in power conversion circuits. This project aims to suppress EMI by significantly improving magnetic components’ EMI suppression performance. The project will develop a fundamental EM theory to bridge the magnetic components’ microscopic EM behavior with their macroscopic electrical performance. Advanced design technologies will be developed based on the developed EM theory to drastically improve magnetic components’ performance to suppress EMI without sacrificing energy efficiency. The success of this project will help to advance the fundamental magnetic component theory, remove the EMI barrier, and facilitate the wide adoption of WBG devices in the power conversion industry. This will in turn increase energy efficiency, reduce CO2 emission, and air pollution toward net-zero-carbon, provide more education, commercialization, and economic opportunities, and improve our life quality. The objective of this project is to explore the fundamental electromagnetic mechanism of the high-frequency impedance peaks and valleys of magnetic components in power electronics systems and develop design technologies to steer these impedance peaks and valleys for EMI suppression. This project will first develop a time-varying electromagnetic theory to characterize the EM behavior inside the magnetic cores of the magnetic components. The impacts of magnetic material characteristics, electrical parameters, and cores’ physical dimensions on the EM behavior inside the cores will then be investigated. The relationship between the microscopic EM phenomena inside the cores and the macroscopic terminal impedance characteristics of magnetic components will be further disclosed based on the developed theory. Finally, novel design technologies to drastically improve magnetic components’ HF impedance performance for EMI suppression will be developed. The developed EM theory and design technologies will be validated by both the EM simulations using finite element analysis and laboratory prototype experiments. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.