汽车电动助力转向系统动力学研究与仿真车辆工程专业论文.docxVIP

摘要摘 摘要 摘 要 汽车电动助力转向(EPS)系统具有节能环保、有效提高车辆安全性及稳定性 等诸多优点，正逐步取代传统的液压动力转向，成为动力转向的新趋势。电动助 力转向系统采用电动机直接提供助力，助力大小由电子控制单元计算并控制，能 实时根据车辆的运行状态和驾驶员地转向操作，提供与之相适应的助力，使汽车 在低速行驶转向时具有良好的轻便性，在高速行驶转向时具有更好的稳定性。 电动助力转向系统的性能优势使之成为现今汽车技术的研究重点之一，论文 以多体系统动力学理论为基础，应用机械动力学仿真软件ADAMS建立整车虚拟 样机动力学模型，模型包括前后悬架、转向系统、轮胎及路面，进行整车稳态转 向仿真试验；探讨适合EPS的转向轻便性、转向回正性、转向盘中间位置区域性 能、转向盘振动以及随动灵敏度评价指标；系统分析了电动助力转向系统理想助 力特性的特征形式，并分析了确定助力特性的一般过程，为研究转向轻便性与路 感提供了方法；确定了一种直线型助力特性，结合建立的虚拟样机动力学模型， 实现了EPS的基本助力控制；对基于ADAMS／Controls与MATLAB／Simulink的 EPS系统联合仿真进行研究，对EPS系统施加PID控制，进行一系列的动力学仿 真试验，说明联合仿真对研究电动助力转向系统的动力学特性是有效可行的。 关键词： 汽车； 电动助力转向系统； 动力学； 仿真 ABSTR ABSTR ACT AB STRACT EPS(Electric Power Steering)has the advantages of saving fuel，producing less pollutions，improving driving security and stability．It is taking the place of HPS gradually and becoming the new developing direction for automobile power steering． The assist torque is provided by motor directly in EPS system，whose value is accounted and controlled by ECU．It Can real time supply assist torque according to the status of the automobile movements and driver’S handling．Automobile can meet the requirements of the excellent maneuverability for low speed and the stability for high speed． The predominance of EPS makes it become an important target of current technology．Based on the theory of Multi—Body system dynamics，the models of full automobile ar e built by the mechanical system simulation software．Multi-body dynamic models of full automobile equipped with EPS is built；the object evaluation of steering performance of EPS is studied；The ideal form and basic parameters of EPS assist characteristic，the method to built assist characteristic are analyzed；Combined wim the virtual model，a type of automobile assist curves is built．The CO—simulation method of ADAMS／Controls and MATLAB／Simulink is practised，the control model and the timing system of motor are established in MATLAB／Simulink．The simulation test is carry out with the control of PID，it proves that it is a viable pro