【作者】 刘海泉；

【导师】 陈翀；

【作者基本信息】 西华大学 ， 车辆工程， 2006， 硕士

【摘要】 随着汽车的高速发展,对汽车操纵的轻便性及灵活性要求越来越高。传统的液压式动力转向系统,存在着结构复杂、价格高、维修保养困难等缺陷,其应用范围受到了一定的影响。而电动助力转向系统(简称EPS)可广泛应用于轻型汽车及高档轿车上,并可提高汽车的操纵灵活性。 汽车EPS是集环保、节能、安全、舒适为一体的机电一体化高新技术产品,与液压助力转向技术有了很大区别,其对转向轻便性、回正性等带来了新的影响,因此需要建立一套测试系统来检测转向系统各方面的性能。由于实车与台架实验存在一定的区别,要在实验台架上得到较理想的转向性能,需要有一套模拟加载装置。如何准确模拟路面对转向系统的阻力作用是进行汽车EPS性能台架仿真试验的重要前提。单纯的液压加载和弹簧加载已经不能满足性能要求,需要一种动态负载仿真系统来实现加载,以满足模拟不同路面、不同车速下转向阻力的要求。论文研究的内容主要是汽车EPS测控系统及电液加载装置的理论分析和试验研究。 本文首先对液压加载系统包括电液伺服加载和电液比例加载系统进行了理论分析,并建立了数学模型。采用MATLAB软件对液压加载系统进行了时域、频域仿真分析。根据系统分析及仿真,从实际要求出发,兼顾加载系统性能需求、价格等诸多因素,经过众多加载方案比较后,从而确定了以电液比例加载为最终的加载方案。探讨了以电液比例溢流阀为液压系统核心部件的一种电液比例加载系统。 本文开发了基于组态软件LabVIEW的汽车EPS性能台架实时测控系统软更多还原

【Abstract】 With the development of high speed in automobile, the requirement of handiness and flexibility on manipulation is increasingly high. The traditionally hydraulic power steering system has limitation of complex structure, high cost, difficult services, and so on, so it has limited scope of application. And that the electric power steering (EPS) is widely spread in small automobile and saloon car, and can improve maneuverability and flexibility.Electric power Steering is high new techno-product integrated of environment protection, saving energy, security, comfortability, which has large difference and brings new effects on steering maneuverability, steering returnability, etc compared with hydraulic power steering. Therefore it is necessary to build a testing system to check and measure performance of every aspect in steering system. Because of the difference between true condition and test-bed, it is necessary to establish a simulated loading device in order to gain ideal steering performance. How to simulate the forces of road and apply it onto the steering system is the premise of doing experiment for performance of EPS of automobile in test-bed. Simplex hydraulic loading and spring loading have not satisfy the required performance, in order to satisfy simulating the requirement of steering resistance at various road condition and velocity, it is needing importantly dynamic loading system to realize it. Theory and experiment are studied on the hydraulic loading.The mathematical model is established firstly on the hydraulic loading in the paper, including electrohydraulic servo and proportional loading. The dynamic performance analysis to the system is also given, including time and frequency responses. The dynamic performances are improved through emendation in order to satisfying the performance of EPS system. Confirming electrohydraulic loading finally after comparing many methods of loading considering performance, price, etc according practical application. A kind of hydraulic loading system, with a proportional electrohydraulic pressure valve as its core component, is presented here.The paper develop a suit of measurement and control software of EPS. The computers carry out the tasks of friendly human-machine interface, easy data acquisition and stable measures of dealing troubles on Lab VIEW platform, and friendly HMI (Human-Machine Interface) measurement & controlling system. Including date acquirement, real time control, signal production, signal disposal module. Date acquirement can gain forces, torque, corner, etc signal of sensor;the realization of proportional pressure valve and electromagnetic direction valve by control module;simulating velocity and engine speed by signal production in order to the design of controller of EPS;signal disposal can analysis in relation to breadth, phase and filter. Based on priorities setting and execution systems selection, a multi-task scheduling based on Lab VIEW for a measurement and control system is presented. These advanced technologies are employed to enhance the performance of measurement and control system. Steady control performance, time, frequency, etc are done by utilizing loading system, measurement and control procedure can further do analyzing and graph drawing.The results of experiments show that hydraulic loading system can satisfy the performances of EPS of automobile. The results of experiments indicate the design of the hydraulic loading and the whole measurement and control system is feasible.更多还原