基于整车多体动力学模型的电动助力转向虚拟试验研究

【作者】 马星辰；

【导师】 王良模；

【作者基本信息】 南京理工大学 ， 车辆工程， 2008， 硕士

【摘要】 电动助力转向系统(Electric Power Steering,EPS)属于一种动力转向系统,比传统动力转向系统具有更高的可控性,能较好地解决汽车转向“轻”和“灵”的矛盾,是汽车电子化发展的成果之一,具有广泛的应用前景。在对EPS系统性能的仿真研究中,建模及控制策略是两大关键问题。由于整车模型自由度过多和EPS控制算法的复杂性的原因,使用一种软件进行基于整车的EPS系统性能分析是比较困难的。本文以某轿车为对象,采用虚拟样机软件ADAMS/Car建立整车多体动力学模型,通过转向盘角阶跃试验、角脉冲试验及转向轻便性等虚拟试验进行整车操稳性仿真和评价,得出虚拟样机与实际车辆具有较好的一致性;依据所建虚拟样机模型,确定了一种直线型助力特性曲线,在MALAB中建立起EPS系统的闭环PID控制系统模型;采用ADAMS/Control模块使机械系统和控制系统之间形成闭合回路,将EPS控制系统与整车模型相结合,进行机电一体化联合仿真。通过对装有和不装EPS系统的整车虚拟试验的对比研究,分析了EPS系统的控制效果及其对整车操纵稳定性的影响。结果表明,闭环PID控制的EPS系统在提高汽车低速行驶转向轻便性和高速行驶转向平稳性方面具有明显作用。更多还原

【Abstract】 Electric power steering system (EPS) is the inevitable developing trend for automobile power steering, which is much superior to conventional power steering system. It is a dynamic steering control system which can supply real-time assist torque according to the status of the automobile movements and driver’s requirements.As it is so difficult to analyze performance of the EPS using single software, the method of co_simulation provides a different way to research the performances of EPS. In this paper, based on the t virtual prototyping technology, a multi-body system dynamics model of full vehicle are built in the mechanical system simulation software, ADAMS/Car. Using Adams/Control module, co_simulation model is established to link the control model established in MATLAB to multi-body system dynamics model of full vehicle in ADAMS/Car. And co_simulation of full vehicle equipped with EPS system were performed in order to study the evaluation and control strategy of EPS.The simulation is then carried out using the established co_simulation model, the outcomes of the study show that, automobile equipped with EPS can meet the requirements of the maneuverability for low speed driving and the stability for high speed driving.更多还原