摘要
轮毂电机驱动的电动汽车簧下质量大导致轮胎动载荷增加,电机电磁力也会加剧车辆振动,同时车辆和道路通过动态轮胎力相互耦合。为了探究电动汽车的振动机理,建立电动汽车机-电-路耦合系统非线性动力学模型,考虑悬架刚度、阻尼和轮胎刚度的非线性,并在传统路面不平顺激励的基础上叠加了轮毂电机的电磁激励和车路耦合引起的路面二次激励。解析推导电机电磁激励的表达式,建立轮毂电机三维实体有限元模型,计算磁通分布及电磁转矩,验证理论结果的有效性。利用模态叠加法推导了两端简支黏弹性地基梁的垂向位移响应,将其作为路面二次激励引入耦合系统模型。以车身加速度、悬架动挠度、轮胎力和轮胎四次幂合力作为评价指标,分析电磁激励、路面二次激励、车速和车辆非线性对车辆平顺性和道路友好性的影响。研究发现,车辆非线性对车辆振动和道路友好性的影响最大,电磁激励的影响次之,路面二次激励的影响较小;车辆高速行驶时,车身振动加剧且车辆载荷对道路损伤的影响更为显著;路面越平坦,以上三个因素的影响越大。所提出的车辆与电机、道路一体化建模思路,可为电动汽车动态设计和道路友好性研究提供借鉴。
The increase in the unsprung mass of the electric vehicle driven by the in-wheel motor enlarges the tire dynamic loads, and the electromagnetic force of the motor will aggravate the vehicle vibration too. In the meanwhile, the vehicle and the road are interacted with each other through dynamic tire forces. In order to explore the vibration mechanism of electric vehicles, a non-linear dynamic model of the mechanic-electro-road coupling system for the electric vehicle is established, which takes into account the non-linearity of suspension stiffness, damping and tire stiffness. Based on the traditional road surface irregularity excitation, the electromagnetic excitation of the in-wheel motor and the road secondary excitation caused by the vehicle-road coupling are also considered. The expression of the electromagnetic excitation of the motor is analytically deduced, the three-dimensional solid finite element model of the in-wheel motor is established, the magnetic flux distribution and electromagnetic torque are calculated, and the validity of the theoretical results is verified. The modal superposition method is used to derive the vertical displacement response of the viscoelastic beam on the foundation simply supported at both ends, which is the secondary excitation of the road considered in the coupled system model. Taking vehicle body acceleration, suspension dynamic deflection, tire force and tire quartic force as evaluation indicators, the effects of electromagnetic excitation, road secondary excitation, vehicle driving speed and vehicle nonlinearity on vehicle vibration and road friendliness are analyzed. It is shown that vehicle nonlinearity has the greatest impact on vehicle vibration and road friendliness, followed by electromagnetic excitation, and road surface secondary excitation;When the vehicle is running at higher speed, the vehicle body vibration intensifies and the impact of vehicle load on road damage is more significant;On the flatter road, the influences of the above three factors are more obvious. The proposed vehicle and motor, road and integrated modeling ideas can provide reference for the dynamic design of electric vehicles and road-friendliness research.
作者
李韶华
罗海涵
冯桂珍
杨建森
LI Shaohua;LUO Haihan;FENG Guizhen;YANG Jiansen(State Key Laboratory of Structural Mechanical Behavior and System Safety of Traffic Engineering Structures,Shijiazhuang Tiedao University,Shijiazhuang 050043;School of Mechanical Engineering,Shijiazhuang Tiedao University,Shijiazhuang 050043;CATARC(Tianjin)Automotive Engineering Research Institute Co.,Ltd.,Tianjin 300300)
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2021年第12期51-61,共11页
Journal of Mechanical Engineering
基金
国家自然科学基金资助项目(11972238)。
关键词
电动汽车
电磁激励
路面二次激励
平顺性
道路友好性
electric vehicle
electromagnetic excitation
secondary excitation of road surface
ride comfort
road friendliness