Abstract: The booming noise of a hybrid vehicle at little accelerator pedal hybrid electric vehicle direct drive modal are studied. The noise occurs at the engine speed of 2 200 r/min. Through noise and vibration measurements, and by using the signal processing methods such as order analysis, it is confirmed that the booming noise comes from the engine the fourth order, which are transferred and amplified from high voltage harness brackets. Through test, it is found that the mode of high-voltage harness support is 150 Hz, coupled with the fourth order noise at hybird electric vehicle direct drive modal. Based on test results, the simulation model is established. According to the hybrid vehicle control unit acceleration shift point and the modal frequency avoidance strategy, the modal target of the bracket is proposed to be 180 Hz, and optimize the structure. And than the mode of the high voltage harness support system are optimized. The real vehicle verified that the fourth order booming noise is reduced by 3 dB(A) after the modes are improved.

Key words: High voltage harness brackets; Hybrid vehicle; Hybrid electric vehicle direct drive modal; Fourth order booming noise

摘要： 针对某搭载混合动力系统的车型在混联一挡小油门加速过程中，发动机转速在 2 200 r/min 时出现嗡嗡声。通过排查悬置、排气、高压线束管路等传递路径，采用带通滤波、阶次分析 等信号处理技术，确认嗡嗡声为发动机四阶噪声通过高压线束支架共振放大，经过此结构路 径传递到车内。测试发现高压线束支架模态为 150 Hz，与混联一档模式下四阶共振。根据整 车控制器的加速换挡点及模态避频策略，提出支架模态目标为 180 Hz，并进行结构优化。结 合测试结果建立仿真模型并优化提升高压线束支架系统模态，实车验证模态提升后四阶轰鸣 降低 3 dB(A)。

关键词: 高压线束支架；混合动力车；混联一挡模态；四阶轰鸣