Enhancement of the Newly Developed Nanocrystalline Ribbon Bidirectional Wireless EV Charging System

Project: Research

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The decarbonization of road transport through the use of ultralow emission electric vehicles (EVs) is critical for mitigating climate change and improving air quality. However, state-ofthe- art batteries for EVs exhibit considerably lower energy density than fossil fuels (265 Wh/kg for Li-ion battery, only 2.2% of 12200 Wh/kg for gasoline), which significantly compromises the EV driving range. Without foreseeable breakthroughs in battery technology, frequent and convenient battery charging is the only way to enable EVs as the dominant means of green decarbonized transportation.  Most current fast EV chargers require drivers to connect a tethered electrical outlet to the vehicle, which leaves drivers prone to hazards. By contrast, wireless power transfer (WPT), the most popular of which is known as inductive power transfer (IPT), eliminates the need for physical contact and enables unobtrusive and hassle-free charging. Since EVs can serve as mobile power plants to support and stabilize the power grid or household power with renewables, the development of vehicle-to-grid (V2G) or to-home (V2H) technology is promising. Therefore, bidirectional wireless EV charging/discharging can be seamlessly integrated into the IPT and can eliminate plug-in forgetfulness in our daily life. Although considerable advances in bidirectional IPT have been achieved in the last ten years, some bottleneck issues, such as low saturation of ferrite core and the parallel SiC MOSFET topology, are still awaiting enhanced solutions. This project aims to develop a novel WPT4 22 kW Nanocrystalline IPT system for a bidirectional wireless EV charging system with high energy efficiency and power density. The new laminated Nanocrystalline ribbons with less than 18 μm thickness are optimally designed as the magnetic core, which would reduce core loss by 14.8%, compact size by 20%, and improve saturation to 1.2 T. In addition, the quadrilateral current mode (QCM) switching scheme is proposed for the parallel connected SiC MOSFETs by artfully utilizing the LCC compensation network as the distributed commutation inductors to achieve zero-voltage switching for all MOSFETs. Furthermore, a dual-active topology that incorporates the QCM scheme and triple-phase shift control is proposed to attain comprehensive controllability, low switching loss, and superior thermal balance. The successful completion of this project will further enhance system performance and lead the bidirectional IPT system to a new height. Beyond the scientific contribution across the globe, the cutting-edge technologies developed in this project will have a crucial real-world application in reducing energy consumption and improving the user convenience of wireless EV chargers. 


Project number9048240
Grant typeECS
StatusNot started
Effective start/end date1/01/23 → …