VHF rectification for fleet and HGV wireless charging solutions

该项目旨在开发VHF整流作为机队和HGV无线充电解决方案的关键部分。感应动力投影有限公司是该项目的负责人，华威制造集团将提供学术支持。关于道路交通的温室气体排放，存在广泛的社会政治问题，英国的战略是鼓励广泛采用电动汽车。无缆无线功率传输(WPT)(也称为感应功率传输)可以潜在地克服有线电动汽车充电器的缺点，并代表着一种潜在的变革性方法，可以改善电动汽车的运营和用户体验。除了方便之外，WPT还可以大幅缩小车载电动汽车电池的尺寸，并具有在移动中为电动汽车动态充电的潜力。尽管WPT解决方案正在被广泛探索，但由于功率密度低，充电速度很慢；虽然制造商声称WPT已准备好上市，但传输距离(覆盖范围)很差，发射器/接收器线圈的角度不对准经常导致电池无法充满电。然而，最大的挑战是重型车辆。与WPT目前所能提供的服务相比，这些服务需要更高的费率和更多的覆盖范围。解决充电率问题以及覆盖范围和不对准问题的唯一方法是显著提高磁场中的功率密度。功率密度可以通过几种方法提高，但基于最先进的铜线圈的WPT系统已经得到了高度优化。增加运行频率将满足技术挑战，但会导致不可接受的功率损失，从而增加运行成本。导电线圈是没有出路的。新兴的第二代汽车频率标准是85 kHz，由第一代的20 kHz发展而来。在85 kHz以上存在一个“困难区域”。然而，在降低成本的情况下，通过增加功率密度来显著提高WPT系统的充电率、覆盖范围和对失调容差的稳健性，仍是一种强烈的业务需求。为此，我们使用VHF技术提供了一种全新的能力，它超越了“困难区域”，提供了极大的功率密度。到目前为止，还没有人能够制定出大功率VHF-WPT，但整改是一个主要障碍，需要解决才能实现我们技术的商业潜力。WPT中已经使用的功率二极管切换速度不够快。可以足够快开关的VHF二极管被用于中等效率可以容忍的较小信号的环境中。因此，该项目将开始为VHF-WPT的高功率VHF整流解决方案建立新的能力。

This project aims to develop VHF rectification as a key part of fleet and HGV wireless charging solutions. Inductive Power Projection Ltd is the project lead, and Warwick Manufacturing Group is to provide the academic support.There are wide-ranging socio-political issues concerning road transportation's greenhouse gas emissions, and the UK's strategy is to encourage broad adoption of EVs. Cable-free wireless power transfer (WPT) (also known as inductive power transfer) can potentially overcome the drawbacks of wired EV chargers, and represents a potentially transformational method for improving the EV operation and user experience. Aside from its convenience, WPT can significantly downsize the onboard EV battery, and has potential for dynamically charging EVs on the move. Although WPT solutions are being widely explored, charging rates are slow because the power density is low; and while manufacturers claim WPT is market ready, the transmission distance (reach) is poor, and angular misalignment of transmitter/receiver coils regularly results in batteries not receiving full charge. However, the greatest challenge is with heavy-duty vehicles. These require much higher charge-rates and more reach than WPT can currently offer. The only way to solve the charge-rate problem, as well as the reach and misalignment problems, is to significantly increase power density in the magnetic field.Power density can be increased in several ways, but the state-of-the-art copper-coil based WPT systems are already highly optimised. Increased operating frequency will meet the technical challenge but leads to unacceptable power losses and therefore more operating costs. There's no way out for conducting coils. The emerging 2nd-generation frequency standard for automotives is 85kHz, rising from 20kHz with 1st-generation. A "difficult region" exists above 85kHz. Nevertheless, there's a strong business need to significantly increase charging rates, reach and robustness to misalignment tolerance of WPT systems by increasing the power density, at reduced costs. To this end, we offer a completely new capability using VHF technology that transcends the "difficult region" and delivers greatly enhanced power densities.Until now, nobody has been able to formulate high-power VHF-WPT, but rectification is a major barrier and needs to be addressed before the commercial potential of our technology can be realised. Power diodes already used in WPT can't switch fast enough. VHF diodes that can switch fast enough are used in the context of smaller signals where moderate efficiency is tolerable. This project will therefore start to build a new capability for high-powered VHF rectifier solutions for VHF-WPT.