VHF Wireless Power Transfer

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(EVS)。无电缆无线功率传输(WPT)(也称为感应功率传输)可能会克服有线电动汽车充电器的缺点，并代表着一种改善电动汽车运营和用户体验的潜在变革性方法，特别是在机会充电的情况下，例如对于装卸区的面包车。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。WPT存在显著的障碍。功率传输效率高度依赖于车辆上发射器线圈(通常埋在地下)和接收器线圈的精确对准。重型电动汽车还需要比WPT目前提供的充电费率高得多的充电率。增加WPT系统的运行频率可以增加功率密度，解决这两个问题，使WPT更具全方位的吸引力。最先进的系统工作在85 kHz，原因有很多，包括铁氧体磁芯的使用、集肤效应和可用的电力电子设备。感应电力投影有限公司最近发明并保护了一种新的方法，可以为不同的应用创造VHF磁场。我们不受频率限制，因此工作在VHF频段(大致定义为30 MHz-300 MHz)。在咨询了高级推进中心后，我们意识到了VHF-WPT为电动汽车充电的潜在价值，并在与华威材料集团进行技术同行审查后，很明显，通过使用VHF，我们避免了85kHz以上的“困难频率区域”。以我们目前的理解，我们的VHF-WPT充电方法可以投射到每个模块400千瓦以上，很容易达到800毫米的非常高的效率(无线部分的效率为99%)；这与目前最先进的WPT系统相比，50千瓦/模块被认为是很好的，雄心勃勃的目标是300毫米。我们已经确定了500毫米横向偏差的艰难目标，即使没有大型车载接收器线圈，我们也可以超过这一目标。然而，需要研究和测试VHF-WPT的可行性，以便更好地了解限制，而这个项目使用我们已经拥有的设备和我们以前工作中开发的技术做到了这一点。我们的解决方案有很大的市场机会，但我们的两个研究机构合作伙伴将努力填补两个已确定的技术差距。

There are wide sociopolitical issues concerning road transportation's greenhouse gas emissions, and the UK's strategy is to encourage wide adoption of electric vehicles (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, especially with opportunity charging, for example for a van in a loading bay. Aside from its convenience, WPT can enable significant downsizing of the onboard EV battery, and has the potential for dynamically charging EVs on the move.Significant snags for WPT exist. The power transfer efficiency is highly reliant on precise alignment of the transmitter coils (usually buried in the ground) and the receiver coils on the vehicle. Heavy-duty EVs also require much higher charge rates than WPT can currently offer.Increasing the operating frequency of WPT systems increases the power density, solving both these issues and making WPT far more attractive all-round. State-of-the-art systems work at 85 kHz for a host of reasons including the use of ferrite cores, the skin effect, and available power electronics.Inductive Power Projection Ltd have recently invented and protected a new way to create VHF magnetic fields for different applications. We're not frequency-limited and so operate in the VHF band (loosely defined as 30MHz-300MHz). After consulting with the Advanced Propulsion Centre, we realised the potential value for VHF-WPT for charging EVs, and following a technical peer review with Warwick Materials Group, it became clear that by using VHF we avoid a "difficult frequency region" above 85kHz.With our present understanding, our VHF-WPT charging method can project in excess of 400 kW per module, easily to 800 mm at very high efficiencies (\> 99% for the wireless part); this compares with current state-of-the-art WPT systems where 50 kW/module is considered excellent, and an ambitious target for reach is 300 mm. A tough target of 500 mm lateral misalignment has been identified, which we can exceed even without a large vehicle-side receiver coil. However, the feasibility of VHF-WPT needs to be studied and tested in order to better understand the limitations, and this project does that, using the equipment we already own, and techniques developed during our previous work.There's a significant market opportunity for our solution, but two identified technology gaps will be worked on by our two research organisation partners.