【作者】 王凯；

【导师】 罗哲； 张建武；

【作者基本信息】 上海交通大学 ， 车辆工程， 2013， 硕士

【摘要】 采用混合动力驱动的汽车的振动噪声问题要比常规汽车更加复杂,其扭转振动及引起的车内噪声对混合动力汽车NVH品质有着重要影响。研究其传动系统扭转振动特性也就具有更重要的理论和应用价值。为解决某型混合动力汽车的传动系统扭转振动与噪声问题,本文建立了复合行星轮系和整车传动系统的扭转振动力学模型,并对传动系统分别进行自由扭转振动分析及强迫扭转振动分析。为进行动力学分析,要确定传动系统各部件的动力学参数。该混合动力汽车传动系统的复合行星齿轮机构采用拉威娜(Ravigneaux)行星齿轮机构。复合行星齿轮机构的动力学模型的建立是整个传动系统建模的重点。固有振动特性(固有频率和振型)对传动系统的动态响应以及振动的形式有重要的影响。本文通过对传动系统固有频率的计算与仿真,分别得到了纯电动工况与混合动力工况下的振动模态,为传动系统的动态特性分析提供了理论基础。在计算传动系统的固有频率基础上,通过扭转减振器的刚度匹配实现共振转速的优化。研究发现,系统共振转速在某特定转速比下出现共振特性且在一定范围内随减振器刚度增大而增大。通过减小减振器刚度可以使共振转速远离发动机怠速转速范围,从而提高整车平顺性和乘坐舒适性。另外,分析了传动系统的动力学幅频与相频特性。在ADAMS中,通过加载激励到动力学模型中,进行动力传动系统强迫扭振仿真分析。在本论文中通过建立虚拟齿轮副模型来建立行星轮部分动力学模型。重点研究了传动系统各参数变化在不同激励源下对动力学特性的影响,包括扭转减振器阻尼系数与刚度、飞轮转动惯量、左右半轴刚度与阻尼以及车轮的扭转刚度。另外,对混合动力传动系各部件在纯电动工况和混合动力工况下的时域响应进行了分析。为确定噪声激励源,对动力合成箱进行噪声测试,并与所建动力学模型中仿真计算得出的固有频率与振型进行对比。研究发现,齿轮副啮合是该传动系的主要噪声源,而扭转振动是引起传动系噪声的重要原因。在试验与仿真计算的基础上,研究不同参数对传动系统的影响方式与影响程度,为传动系统的减振降噪提供可靠的参数优化及匹配方案。更多还原

【Abstract】 The vibration and noise problems of vehicles with hybrid drive are more complicated than those of the conventional vehicles, which have significant impacts on the NVH quality of the hybrid electric vehicle. The research on the characteristics of the torsional vibration on the driveline of vehicle has great theoretical and practical values.In this research, a dynamic model of the compound planetary gear sets and the whole transmission system are established respectively for the free and forced torsional vibration analysis of the Hybrid Electric Vehicle(HEV).The dynamic parameters of the components of the driveline are calculated. “Ravigneaux” gear set is applied in this transmission system. So the modeling of the compound planetary gear set is the most important part of the whole driveline system.Natural vibration characteristics are composed of natural frequency and vibration mode which have significant impacts on dynamic response and vibration forms. Through the analysis and calculation of natural frequency and vibration mode, the vibration modes of the driveline system under hybrid electric condition and pure electric condition are obtained, which provide the theoretical basis for the dynamic characteristic analysis of the driveline system. On basis of the calculation the natural frequency, resonant speed of the powertrain was optimized through the stiffness matching of torsional damper. The analysis results indicate that the resonant speed can be reduced out of the engine idling speed range by decreasing the stiffness of the torsional damper. Besides, the amplitude-frequency and phase-frequency characteristics of the driveline system are analyzed.The forced torsional vibration of the driveline model is simulated in ADAMS. In this paper, the dynamic model of the compound planetary gear set is established by adding virtual gears. The studies focus on the driveline system parameters change on the dynamic characteristics, including damping coefficient and stiffness of the torsional damper, moment of inertia of the flywheel, damping coefficient and stiffness of axle shaft and torsional stiffness of the wheels. Besides, the time domain responses of the components of the driveline are respectively analyzed under hybrid electric condition and electric condition.For the purpose of determining the noise excitation source, the acoustic test of the powertrain is needed. Comparing with the results of acoustic test, the natural frequency and vibration mode of the system are analyzed. It is demonstrated that the noise is mainly caused by the engagement of gear pairs. Moreover, numerical results show torsional vibration has a significant impact on the noise of transmission system.According to the results of the test and simulation, the influence manner and the influence degree on the driveline system of different parameters are discussed in order to find feasible solution to minimize the vibration and noise by optimizing some parameters.更多还原