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

现代电源转换电路产生的电磁干扰是对所有电子电路和设备的一种电磁污染。宽带隙（WBG）器件是一种高速半导体器件，可以减少能量损耗、成本和功率转换电路的尺寸，因此被认为有希望取代功率转换电路中的传统Si器件。然而，它们的高速导致比传统Si器件更高的EMI，这减缓了WBG器件在功率转换行业的广泛采用。在功率转换电路中，电感和变压器等磁性元件在产生和降低电磁干扰方面起着重要作用。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。该项目将发展一个基本的电磁理论，以连接磁性元件的微观电磁行为和宏观电性能。先进的设计技术将基于已开发的电磁理论，在不牺牲能源效率的情况下大幅提高磁性元件的性能，以抑制电磁干扰。该项目的成功将有助于推进磁性元件的基础理论，消除电磁干扰障碍，促进WBG器件在功率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，实现净零碳排放，提供更多的教育、商业化和经济机会，并提高我们的生活质量。该项目的目标是探索电力电子系统中磁性元件高频阻抗峰谷的基本电磁机制，并开发设计技术来控制这些阻抗峰谷以抑制电磁干扰。该项目将首先发展时变电磁理论，以表征磁性元件磁芯内的电磁行为。然后将研究磁性材料特性、电气参数和磁芯物理尺寸对磁芯内部电磁行为的影响。在此基础上，将进一步揭示磁芯内部微观电磁现象与磁性元件宏观端阻抗特性之间的关系。最后，将开发新的设计技术，以大幅度提高磁性元件的高频阻抗性能，以抑制电磁干扰。所开发的电磁理论和设计技术将通过有限元仿真和实验室原型实验进行验证。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值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.