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

现代功率变换电路产生的电磁干扰(EMI)是对所有电子线路和设备的电磁污染。宽带隙(WBG)器件是一种能降低能量损耗、降低成本、减小功率转换电路体积的高速半导体器件，被认为有望在功率转换电路中取代传统的硅器件。然而，它们的高速导致了比传统硅器件更高的EMI，这阻碍了WBG器件在电力转换行业的广泛采用。包括电感和变压器在内的磁性元件在功率变换电路中电磁干扰的产生和减小中起着很大的作用。本项目旨在通过显著提高磁性元件的EMI抑制性能来抑制EMI。该项目将开发一种基本的电磁理论，将磁性部件的微观电磁行为与其宏观电性能联系起来。基于已开发的电磁理论，将开发先进的设计技术，在不牺牲能效的情况下，大幅提高磁性元件的性能，以抑制EMI。该项目的成功将有助于推进基本磁性元件理论，消除电磁干扰障碍，并促进WBG器件在电力转换行业的广泛采用。这将反过来提高能源效率，减少二氧化碳排放，减少空气污染，实现净零碳，提供更多的教育、商业和经济机会，改善我们的生活质量。本项目的目标是探索电力电子系统中磁性元件高频阻抗波峰和波谷的基本电磁机制，并开发设计技术来引导这些波阻抗波峰和波谷以抑制EMI。这个项目将首先开发一个时变的电磁理论来描述磁性部件磁芯内部的电磁行为。然后将研究磁性材料特性、电学参数和磁芯的物理尺寸对磁芯内部电磁行为的影响。基于发展的理论，将进一步揭示磁芯内部的微观电磁现象与磁性元件的宏观终端阻抗特性之间的关系。最后，将开发新的设计技术，以显著改善磁性元件的高频阻抗性能，以抑制EMI。开发的电磁理论和设计技术将通过使用有限元分析的电磁模拟和实验室原型实验进行验证。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

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.