CAREER: High-Frequency Power Electronics for Wireless Power Transfer Systems

无线电能传输(WPT)通过在从电动汽车(EVS)和机器人到便携式电子产品和生物医学植入物的各种应用中实现自动充电，具有解决关键能源问题和改善人类生活质量的潜力。例如，高效、小巧、经济高效和安全的WPT可以大幅减少对昂贵而笨重的车载电池的需求，扩大续航里程，并加快电动汽车的普及。由于公路运输占美国总能源消耗的22%，电动汽车的行驶效率大约是汽油车的两倍，即使是10%的电动汽车普及率(目前为0.1%)也可以使美国的总能源消耗减少1%以上。同样，有效的WPT可以使人工心脏泵无需穿过腹壁的电线，从而避免美国510万心力衰竭患者的不适和潜在的感染。此外，WPT可以消除每年近4万人进行心脏起搏器电池更换手术的需要。然而，要想广泛采用WPT系统，需要在性能、成本和安全性方面进行相当大的改进。这一综合的研究和教育职业发展计划旨在高频(1-100 MHz)电力电子技术方面取得根本性进展，并利用激动人心的WPT应用来点燃未来工程师的想象力。该计划更广泛的教育目标包括培训通过科罗拉多大学(CU)发现学习学徒计划参与的研究生和本科生。将研究成果纳入CU Boulder课程，并通过免费在线课程更广泛地传播研究成果，将加强对CU Boulder、社区学院和其他地方学生的教育。针对K-12学生的特别外展计划，让他们参与制作教育视频，让他们了解电力电子和WPT在提高能效和生活质量方面的作用，并吸引他们追求STEM职业生涯。为了实现WPT系统的效率、尺寸和安全性与有线系统相当的目标，本职业计划的研究目标是：(I)推广PI引入的新的阶跃叠加(S2)分析技术，并利用它来更好地建模和优化具有多个逆变器和/或整流器的高阶谐振变流器；(Ii)创新和采用高阶谐振变流器拓扑结构，在电感和电容WPT系统中适当控制多个逆变器和整流器，以补偿耦合的变化，实现更高的效率和更小的体积，然后通过一系列实验原型验证这些优势；以及(Iii)通过测量具有不同耦合器几何和配置的原型中的边缘场的减少来论证通过分布式WPT架构实现近场聚焦和增强安全性的可行性。这一努力促成了重大创新和根本性进展。这里开发的阶跃叠加分析技术将使WPT应用以及其他电力电子和复杂系统应用的高阶谐振转换器能够精确建模和优化。在证明了高阶多逆变器/整流谐振转换器可在并网电力电子设备中提供能效效益后，PI的研究将推出先进的变种，有效补偿WPT系统中耦合的变化，同时在ISM(即工业、科学和医疗)频段内以固定频率运行。这项研究还将通过为场抵消而设计的分布式耦合器来更好地理解近场相控阵聚焦，并使功率传输密度和安全性得到显著提高。

Wireless power transfer (WPT) has the potential to address critical energy issues and improve human quality of life by enabling autonomous charging in applications ranging from electric vehicles (EVs) and robotics to portable electronics and biomedical implants. For example, efficient, small, cost-effective, and safe WPT can drastically reduce the need for expensive and bulky on-board batteries, extend range, and accelerate EV penetration. With road transportation accounting for 22% of the nation's total energy consumption, and EVs having roughly twice the well-to-wheel efficiency of gasoline vehicles, even a 10% EV penetration (versus 0.1% currently) can reduce total U.S. energy consumption by over 1%. Likewise, effective WPT can enable artificial heart pumps without abdominal-wall-penetrating electric cords, avoiding discomfort and potential infections for the 5.1 million people in the U.S. suffering from heart failure. Furthermore, WPT could eliminate the need for cardiac pacemaker battery replacement surgeries for nearly 40,000 people each year. However, for WPT systems to be widely adopted, considerable improvements are needed in their performance, cost, and safety. This integrated research and education career development proposal aims to make fundamental advancements in high frequency (1-100 MHz) power electronics technologies, and leverage exciting WPT applications to ignite the imagination of future engineers. The program's broader educational goals include the training of graduate research students and undergraduates participating through the University of Colorado's (CU) Discovery Learning Apprenticeship Program. Incorporating the research findings into the CU Boulder curriculum and disseminating the findings more broadly through a free online course will enhance the education of students at CU Boulder, community colleges, and elsewhere. The special outreach program for K-12 students, involving them in the development of educational videos, will expose them to the role of power electronics and WPT in improving energy efficiency and quality of life and attract them to pursue STEM careers. To achieve the goal of WPT systems with efficiencies, sizes, and safety comparable to their wired counterparts, the research objectives of this CAREER proposal are to: (i) generalize the new step-superposition (S2) analysis technique introduced by the PI, and use it to better model and optimize high-order resonant converters with multiple inverters and/or rectifiers; (ii) innovate and employ high-order resonant converter topologies with appropriately controlled multiple inverters and rectifiers in inductive and capacitive WPT systems to compensate for changes in coupling and achieve higher efficiency and reduced size, then validate these advantages through a series of experimental prototypes; and (iii) demonstrate feasibility of near-field focusing and enhanced safety through distributed WPT architectures by measuring the reduction in fringing fields in prototypes with different coupler geometries and configurations. This effort enables important innovations and fundamental advances. The step-superposition analysis technique developed here will enable accurate modeling and optimization of high-order resonant converters for WPT applications, as well as other power electronic and complex system applications. Having demonstrated high-order multi-inverter/rectifier resonant converters to provide efficiency benefits in grid-interfaced power electronics, the PI's research will introduce advanced variants that effectively compensate for variations in coupling in WPT systems, while operating at fixed frequency within ISM (i.e., industrial, scientific and medical) frequency bands. The research will also yield a better understanding of near-field phased-array field focusing through distributed couplers designed for field cancellation, and enable dramatic advances in power transfer densities and safety.