Evaluating Vibration Test Profiles for Battery Electric and Hybrid Vehicles

As the automotive industry transitions to electrification, understanding the differences in ambient operating vibration environments between a conventional internal combustion engine (ICE) propulsion system, battery electric vehicles (BEV), and hybrid electric vehicles (HEV) becomes increasingly important. Many current automotive vibration testing standards use frequency and amplitude levels based on historical ICE data. Some note the potential inaccuracies of using this data to test BEV/HEV and recommend using recorded field data when possible, while others make no note. Preliminary comparisons of BEV, HEV, and ICE vehicle ambient operating vibration environments show variations due to battery cell pack weight and engine vibration, among other reasons. As accurate testing is tantamount to vehicle safety and longevity, the automotive testing industry must confirm the suitability of current standards for BEV and HEV or create new standards. This paper delves into real-world vibration characteristics that were measured on chassis and powertrain components and systems for all three architectures. It compares the influence of powertrain architecture on vibration levels and frequencies, expressed through the fatigue damage spectrum (FDS) and shock response spectrum (SRS), which model damage response and extreme displacement, respectively. This paper discusses the implications of suitable test levels for vehicle design, reliability, and vibration testing, offering insights for vehicle development and optimization. It also introduces a suggested method of vibration test profile development for BEV/HEV using recorded data and the FDS to improve confidence in test results.