基于dSPACE的EPS系统ECU硬件在环实验台设计与应用

硬件在环仿真测试是ECU研发过程中重要一环,对其性能调试起着关键作用。文章重点阐述基于dSPACE的EPS(电动助力转向)系统ECU(电控单元)硬件在环仿真试验台的设计与应用。基于dSPACE硬件在环仿真器,构建了EPS ECU的硬件在环仿真试验台。通过整合dSPACE系统内部车辆动力学仿真模型与改进的转向系统模型,获得更为接近实车的汽车动力学仿真模型。基于所设计的试验台,对某开发的EPS ECU进行离线测试并分析其性能表现。结果表明,该ECU能较好地满足汽车对转向轻便性、路感及回正性能的要求。     

齿轮齿条式转向系统五轴试验台的设计与研究

设计了齿轮齿条式转向系统五轴试验台。在分析转向系统基本要求、整车转向系统评价标准及转向器行业标准的基础上,提出了该转向系统五轴试验台需实现的试验项目及基本功能,并对电液伺服加载、驱动装置控制、加载装置静压支撑等关键技术进行了探讨。对所研制的转向系统五轴试验台进行验证的结果表明,该试验台能够有效进行齿轮齿条转向系统性能匹配及耐久性测试评价,试验结果与实车试验结果具有较好的一致性。     

汽车动力转向试验台的计算机检测与控制系统

介绍了汽车动力转向模拟试验台的计算机检测与控制系统。阐明了系统的硬件设计、试验组合程序设计、绘图软件设计等。     

转向系统试验台转向阻力模拟研究现状及发展

转向系统对车辆操纵稳定性有极其重要的影响,近年来针对转向系统性能测试的试验台一直是国内外研究的热点,而准确地进行转向阻力模拟,是仿真试验系统研究中的关键,文中详细概述了国内外几种转向试验台转向阻力模拟方式及其各自的优缺点.     

基于系统级的电动助力转向控制测试评价研究

对电动助力转向(EPS)硬件在环(HIL)测试的3种方案进行了对比分析,基于HIL仿真系统和转向试验台,构建了EPS机械系统级的虚拟整车测试平台。研究分析EPS功能和故障诊断测试内容,通过车辆动态转向工况的仿真以及各类故障的注入,对EPS系统控制功能和故障模式下诊断安全策略进行了测试和评价。EPS系统级HIL测试可以在整车试装前使测试更加接近实车,又能覆盖实车难以实现的边界极限及故障工况。     

一种汽车电动助力转向装置总成性能试验台

为提高汽车电动助力转向装置的质量,减轻检测人员的劳动强度,降低生产成本,开发了汽车电动助力转向器总成性能试验台。所开发的汽车电动助力转向系统综合性能试验台,能对C-EPS各种类型的电动助力转向装置的性能进行全面测试。与现有电动助力转向系统综合性能试验台相比,能提供实时的车辆动力学仿真环境,可完成对汽车电动助力转向器总成性能的多项试验。     

基于uCOS—Ⅱ的嵌入式汽车EPS试验台液压控制系统设计

根据汽车电动助力转向系统及路面阻力的特点。分析了电动助力转向试验台液压加载装置的主要功能,设计了基于ARM7的液压控制系统。软件设计中移植了uCOS—Ⅱ操作系统,采用多任务程序设计方法,大大降低了编写程序的复杂度。实验表明系统设计可靠,能够达到良好的控制效果。     

电动助力转向系统阻力模拟器研究及实现

研究电动助力转向系统阻力模拟器的控制方法，探索一种利用单片机控制电动机转矩为试验台提供转向阻力的方法。介绍了阻力模拟器的结构、控制方法、工作原理，研究了电动助力转向系统阻力模拟器的功能及实现方法。     

汽车ESP硬件与驾驶员在回路仿真试验台的开发与应用

利用汽车驾驶模拟器技术和硬件在回路仿真技术,建立了汽车电子稳定性系统(ESP)硬件与驾驶员在回路仿真试验台。利用该试验台进行了包含ESP执行硬件和驾驶员的“人车环境”闭环仿真,验证了试验台的基本功能。该试验台为汽车ESP的开发提供了一个功能比较完备的快速开发平台。     

汽车线控转向系统实验台测试系统的开发与研究

介绍了汽车线控转向试验台测试系统的工作原理与基本构成,并对实验台进行了测试。实际运用表明：该试验台使用方便,运行稳定可靠。测试精度和效率均能满足要求,适用于线控转向系统的基本特性的测试与控制系统的开发。为后续实车试验奠定了基础。     

Torque ripple minimization control of permanent magnet synchronous motors for EPS applications

This paper identifies a control method used to reduce torque ripple of a permanent magnet synchronous motor (PMSM) for an electric power steering (EPS) system. NVH (Noise Vibration Harshness) is important for safe and convenient driving. Vibration caused by motor torque is a problem in column type EPS systems. Maintaining a very low torque ripple is one solution that allows for smoother steering. Theoretically, it is possible to design and drive the motor without torque ripple. However, in reality, a PMSM system torque ripple is caused by the motor itself (saturation in the iron core and EMF distortion) and the imperfect driver. This paper analyzes torque ripple of a PMSM system, and an advanced PMSM control method for the column typed EPS system is presented. Results of the analysis indicate that the compensation current is needed in order to minimize torque ripple when a PMSM is driven.     

电动助力转向系统永磁同步电机故障诊断方法

介绍电动助力转向系统中永磁同步电机的故障诊断方法。重点对初始电机开路诊断法、电流失控诊断法和电压估算诊断法3种电机诊断方法进行了分析。     

基于粘结-滑移理论的钢结构转向体系受力特性研究

为解决钢结构转向体系设计中锚栓受力不明确的问题,采用Abaqus/CAE三维建模软件分别对块式和横隔板式2种钢结构类型的体外预应力束转向体系建立了2种转向体系的有限元模型,并为了精确模拟锚栓的粘结-滑移特性,对锚栓节点采用了非线性弹簧本构,基于有限元计算结果分析了2种转向器受力及变形特性。结果表明:1)块式转向体系结构刚度一般,在转向力作用下锚栓受力较大,结构安全系数较低;2)横隔板式转向体系结构刚度较大,在转向力作用下,结构破坏形态是钢结构屈曲,锚栓受力较小,整个结构安全系数极高。     

Adaptive Control of 4WS System by Using Neural Network

An adaptive control system of the model following type is proposed for drive motion control of a four wheel steering (4WS) car with using neural network (NN) which has mastered nonlinear friction force between tire and road surface. A model of one rigid body is adopted which represents appropriately two kinds of car motion caused by steering action, namely the lateral displacement and the yawing rotation, and an equation of motion is described in a simplified form to make a system equation for motion control possible. Nonlinear relation between the cornering force of tire and the slip angle is obtained by numerical analysis with the tire model proposed by E. Fiala, taking friction coefficient and car speed as the parameters. The result is used as the teaching signal for NN. Three NN are used in the control system composed of both the feed-forward and the feedback circuits in order to realize adaptive control. Validity and usefulness of the proposed adaptive control system with NN are verified by three kinds of computer simulation.     

电流变转向控制器的研究

研制了一种电流变转向器，介绍它的工作原理，结构和控制方法。为了模仿人的行为，采用步进电机，实现多种波形的转动。利用NI虚拟仪器，建立了电流变转向控制机构的自动控制系统。     

Stabilization of Passenger Car-Caravan Combination Using Four Wheel Steering Control

This study aims to stabilize the trailer at high speed. The behavior of passenger cars with four wheel steering system, vehicles with rear wheel steering and of trailer and passenger car are similar. This is regarded as an optimal regulator problem with linear equation of motion, and a state variables feedback control system is adopted. The problem of stability at high speed on a straight course can be solved. Therefore, the passenger car-trailer system can be stabilized. Furthermore, this study indicates the way forward to stabilize a passenger car-trailer system.     

基于增益模糊滑模变结构的线控液压转向控制

在分析全液压转向结构与转向偏差机理的基础上,设计了一种线控液压转向系统以实现车辆转向同步,消除转向偏差;针对现有方法确定的期望转向曲线可跟踪性差而无法实现转向同步,提出一种基于转向效率的期望转向曲线及其可行域确定方法,以最大、最小转向效率对应转向曲线为期望转向曲线可行域的上、下边界,确保期望转向曲线的可跟踪性;针对系统扰动不确定性及油液泄漏非线性,基于组合趋近律滑模控制,并引入饱和函数代替符号函数,在一定程度上抑制了控制系统的抖振;由于组合趋近律增益自适应性不足,导致车轮转角及角速度发生变化时,存在系统动态响应能力差的问题,通过分析车轮转角、角速度与趋近律增益的关系,制定了基于车轮转角及角速度的模糊规则表以自适应调整趋近律增益,实现增益模糊滑模控制,进一步提高油液补偿自适应能力和线控液压转向系统的鲁棒性;最后基于MATLAB/Simulink进行了仿真和试验验证。结果表明：提出的基于转向效率的期望转向曲线均具有良好的可跟踪性能;增益模糊滑模变结构控制具有良好的动态响应特性及控制精度,可有效地消除转向偏差,实现线控液压转向系统的同步转向。     

Adaptive Control of 4WS System by Using Neural Network

SUMMARY

An adaptive control system of the model following type is proposed for drive motion control of a four wheel steering (4WS) car with using neural network (NN) which has mastered nonlinear friction force between tire and road surface. A model of one rigid body is adopted which represents appropriately two kinds of car motion caused by steering action, namely the lateral displacement and the yawing rotation, and an equation of motion is described in a simplified form to make a system equation for motion control possible. Nonlinear relation between the cornering force of tire and the slip angle is obtained by numerical analysis with the tire model proposed by E. Fiala, taking friction coefficient and car speed as the parameters. The result is used as the teaching signal for NN. Three NN are used in the control system composed of both the feed-forward and the feedback circuits in order to realize adaptive control. Validity and usefulness of the proposed adaptive control system with NN are verified by three kinds of computer simulation.     

Effects of FTP-75 mode vehicle fuel economy improvement due to types of power steering system

This paper focuses on fuel economy improvement according to the type of power steering system. Usually, a conventional power steering system is directly driven by the crankshaft of the engine with a belt, known as HPS (hydraulic power steering). However, there is some inefficiency with this system at high engine speeds. To improve this inefficiency, automobile makers have developed two power steering systems: EHPS (electro-hydraulic power steering) and MDPS (motor-driven power steering) or EPS (electric powered steering). However, there has been insufficient study of effects of the type of power steering system on fuel economy. In this paper, the effect of the type of power steering system on fuel economy is studied experimentally, and calculations of the effect on vehicle fuel economy are presenting using computer simulation with AVL cruise software. The results demonstrate that a 1% vehicle fuel economy improvement can be achieved in a vehicle with an electro-hydraulic power steering system compared to a vehicle with a hydraulic power steering system. In addition, a 1.7% vehicle fuel economy improvement can be achieved using a full electric power steering system in a FTP-75 driving cycle. These results could be used to choose a power steering system.     

装备EPS系统特锐样车操纵稳定性客观评价

对装备电动助力转向(EPS)系统的整车操纵稳定性进行评价的必要性进行了分析,介绍了装备EPS的整车操纵稳定性评价的具体内容。给出装备EPS的特锐样车原地转向轻便性、转向盘中间位置操纵稳定性、转向回正性、转向瞬态响应特性(转向盘转角脉冲输入)的试验方法和标准,对其操纵稳定性进行了评价。评价结果表明,所采用的评价方法有效、可行。