Reliability and Efficiency of Electric Vehicle Transmissions

电动车辆（EV）设计对EV变速箱施加了特别苛刻的摩擦学条件。这包括在一个极端的高扭矩和低齿轮速度的组合和在另一个极端的非常高的速度与相对低的扭矩。此外，冷却要求要求使用非传统的润滑液，一些专门为此应用开发的最新润滑剂含有大量的水。这导致传动元件如轴承和齿轮中的恶劣摩擦条件，同时也增加了油搅动损失。该项目旨在优化电动汽车变速器的效率和可靠性。它建议设计一个模型，它是能够预测的摩擦学条件和总功率损失的变速器适用于电动汽车。至关重要的是，该方法将包括齿轮和轴承操作的详细处理，以准确预测这些部件的使用寿命和摩擦损失。这将包括使用目前使用或正在开发的用于电动汽车变速器的润滑剂的测量流变性能。该项目的总体目标是：-通过优化变速器结构（传动比数量，传动比分配，重量）来提高效率，从而增加电动汽车的范围，以提供足够的输入输出匹配给定的车辆负载。- 优化EV润滑油配方，以最大限度地减少变速箱功率损失（从而延长车辆续航里程），同时保持耐用性。润滑剂的考虑将涉及摩擦学性能、冷却、电气性能和材料兼容性。

Electric vehicle (EV) design imposes particularly harsh tribological conditions on EV gearboxes. This includes the combination of high torque and low gear speed at one extreme and very high speeds with relatively low torques at another. In addition, cooling requirement call for unconventional lubricating fluids, with some of the latest lubricants developed specifically for this application containing significant amounts of water. This results in harsh tribological conditions in transmission elements such as bearings and gears while also increasing oil churning losses. This project is concerned with optimising efficiency and reliability of EV transmissions. It proposes to devise a model which is able to predict the tribological conditions and the overall power losses in transmissions suitable for use in electric vehicles. Crucially, the approach will include a detailed treatment of gear and bearing operation in order to accurately predict operational lifetimes and friction losses in these components. This will include the use of measured rheological properties of lubricants currently used or being developed for use in EV transmissions.The overall aims of this project are:- To improve the efficiency and hence increase the range of EVs through optimising transmission architecture (number of ratios, ratio split, weight) required to provide adequate input-output matching for a given vehicle duty. - To optimise EV lubricant formulation to minimise gearbox power losses (and hence extend vehicle range) while maintaining durability. Lubricant considerations will address tribological performance, cooling, electrical properties and material compatibility.