电动汽车悬架运动学优化方法

Optimized Rear-Axle Concept for Battery Electric Vehicles: A Show Case Study for New Suspension Development Methods

摘要:

电池电动汽车（BEV）的主要挑战之一是续航里程是否足够，因此在任何最近的车辆概念中，最大化的电池体积是合乎需要的。悬架作为最大的电动汽车子系统之一，对这一点有着重要的影响。本研究目的是使用自动化方法进行悬架开发，主要是引入一种新的可转向后悬架概念与电力推进系统，即从配备内燃机（ICE）的传统汽车开始，开发一种悬架，以满足纯电动汽车的新装配要求，同时保持有关驾驶动力学的典型要求。悬架概念是为具有大电池尺寸的高级汽车而优化的，此外还考虑了先进的主动系统，如空气弹簧和大转向角的主动后轮转向。该概念还提出了一种具有良好调整运动学性能的封装解决方案，符合原始设备制造商的调整理念。为解决由此产生的高复杂性，使用了新开发的方法，即运动学优化是用一种创新的方法完成的，该方法根据给定的要求自动提出新的硬点。在设计中，使用简化模型来表示复杂零件的形状，因此可以从包装的角度自动判断运动学概念是否可行。结果表明，新的悬架概念可以处理具有挑战性的装配问题和复杂的运动学要求。

Abstract:

One of the main challenges for battery electric vehicles （BEV） is a sufficient range. Therefore， a maximized battery volume is desirable in any recent vehicle concept. Suspension， as one of the largest subsystems， has a significant impact on that. Starting from a conventional car with an internal combustion engine （ICE）， a suspension is developed to fulfill new packaging requirements for BEVs， while at the same time maintaining typical requirements concerning driving dynamics. The objective of this study is to use automated methods for suspension development to develop a new steerable suspension concept for an electric propulsion system. The suspension concept was optimized for premium cars with large battery sizes. Moreover， advanced active systems such as air springs and active rear wheel steering with large steering angles were also considered. The concept proposes a packaging solution with a well-tuned kinematic performance which meets typical tuning philosophies. In order to address the resulting high complexity， newly developed methods were used. The kinematic optimization was done with an innovative method， which automatically proposes new hard points， depending on the given requirements. For the design， simplified models were used to represent the shape of sophisticated parts. Therefore， it was possible to automatically judge whether a kinematic concept is feasible from a packaging point of view. The results show， that the new suspension concept can handle the challenge packaging issues and complex kinematic requirements.