混合动力汽车的发动机会频繁地出现点熄火，提高熄火工况下的动力总成悬置系统的隔振性能是提高汽车NVH性能的重要措施之一。本文建立了动力总成十三自由度模型，在点熄火工况下，计算了悬置主动端的加速度，测试了各个悬置的主、被动端和座椅导轨上振动加速度。测试结果与计算的对比验证了模型的有效性。考虑与不考虑悬置刚度和位置参数的不确定性，提出了两种悬置系统的优化方法，优化目标为减小动力总成纵向加速度的振动剂量值。当悬置的参数为区间不确定时，利用摄动中心差分法计算得到了振动响应的上下界，并用于不确定性优化。试验结果表明，采用确定性优化优化方法时，悬置系统的振动性能最好但稳健性不足，而采用不确定性优化方法得到的悬置系统的振动性能和稳健性都较好。

Hybrid electric vehicles often experiences key-on/off conditions, to increase vibration isolation performance of the Powertrain Mounting System (PMS) under key-on/off conditions is one of the important measures to enhance NVH (Noise , Vibration and Harshness) performance of the vehicle. A model with 13 DOFs for PMS was established , and acceleration of the mounts at active side was estimated under the key-on/off condition. Also vibration acceleration of the mounts and the seat rail were measured. The comparison between calculations and experiments validated the proposed model. Considering or not considering the uncertainty of mount stiffness and locations, two optimization methods for reducing the vibration dose value of longitudinal acceleration of the powertrain were proposed. When the mount parameters were interval uncertain, the upper and lower bounds of the vibration response were calculated using the perturbation center difference method and then used for uncertainty optimization. The experimental results show that if mount parameters are optimized using deterministic methods, the vibration performance of the PMS is the best but the robustness is insufficient, while the vibration isolation performances and robustness of the PMS are compromised using uncertainty optimization methods.

U464.13;U461.4

国家自然科学基金(12272137)