现代汽车发动机的“感觉器官”

随着电子控制系统在汽车上的应用，使得现代汽车焕然一新。发动机电子控制系统主要由电控单元(ECU)、各种传感器及执行器组成。其中电控单元由微机和辅助电路组成，是整个控制系统的核心，用以     

AJR型电控发动机试验台的开发研究

汽车电子电控技术是现代汽车技术的主体,是汽车新技术的具体应用。以桑塔纳2000Gsi轿车电控AJR型发动机试验台的开发研究为例,应用汽车新技术对电控发动机进行改造,把传感器采集到的发动机工作信息,在经过ECU信息处理后,用仪表显示传感器的工作电压,进而监控发动机各部位的工作情况,同时还能根据需要对发动机设置故障,利用发动机自诊断系统或汽车解码器诊断故障部位,提高故障诊断的准确性和诊断速度,尽快排除故障。     

数字万用表在汽车电子器件检测与模拟中的作用

1气车电子信号的主要类型汽车的传感器、执行器的电信号可以看成控制系统中互相通讯的语言。汽车电子信号主要有直流电压信号、交流电压信号、频率调制信号、脉宽调制信号和串行数据信号等。正是这些电子信号利用各自不同的特点,实现了汽车电子控制系统中各传感器与ECU(电子控制单元),ECU与各执行器,ECU与ECU之间的不同通信的目的。     

测片式空气流量传感器的故障检修

测片式空气流量传感器(以下简称空气流量传感器),在L型电子控制汽油发动机上有着比较广泛的应用.它的作用是:直接检测进入发动机气缸的空气量,将空气流量转换成电信号,输送给电子控制单元(ECU).     

数据流在发动机故障诊断中作用

随着经济与科学技术的进步与发展,我国各个行业的制造水平与生产技术都得到了相应的提升,汽车机电一体化产品制造技术也获得了飞跃式发展。当前诸多数据电控技术已经被广泛应用到汽车中,如电控系统、传感器、执行器等部分都是以数据流为核心。在汽车向自动化程度不断加深的背景下,汽车发动机故障已经引起更多人的关注。而数据流技术恰好能够帮助人们解决多种复杂的发动机故障问题,使得汽车修理工可以精准捕捉传感器与执行器工作时状况数据。数据流分析对发动机故障的作用是巨大的,能够通过传感器、电子控制单元与执行器来反映参数,这些数据能够真实的反映汽车内部的器件的工作电压与状态,给发动机故障诊断解决问题提供数据依据。     

电子式汽车机油压力传感器设计

机油压力是汽车发动机的重要参数之一。当机油压力过低时，可能损坏发动机，因此在汽车上需要安装油压表，以监测发动机运行过程中的机油压力。在介绍油压指示表的工作原理以及传统的机油压力传感器的基础上，提出了一种新型的电子式汽车机油压力传感器，详细讲述了传感器的结构、工作原理，并给出了其主要性能指标和实验结果。     

传感器在汽车发动机上的典型应用

论述了汽车发动机用的传感器与发动机控制装置ＥＣＵ控制功能的关系，概述了几种传感器的工作原理及其典型应用。     

发动机ECU标定系统设计

发动机ECU标定系统在我国目前的通用汽车行业中起到重要作用。该标定系统包括数据库单元、监测数据读写单元、CAN通信接口以及监控单元等。数据库单元用于存储控制发动机不同工况点工作状态的控制信号;检测数据单元主要用于标定系统中读取发动机处于不同工作状态的测试信号;而CAN通信接口主要用于连接外围设备。额定值人员对于ECU标定系统的额定值进行处理,保证系统可以根据车况数据及时调整ECU标定系统的策略。相关研究人员根据ECU标定系统的实际情况进行优化处理,很大程度上提高了引擎进行实时数据采集的能力。     

AE300发动机ECU自检和Wizard软件故障诊断

AE300系列发动机是一款煤油压燃式活塞发动机,具有电子发动机控制组件(EECU),ECU自检则是对整个EECU系统的逻辑进行自动控制,检测其功能是否正常。本文通过分析ECU自检的流程,同时让机务维护人员掌握如何使用软件对发动机信息和数据进行分析。     

ECU信号模拟器在发动机故障诊断中的研究与应用

发动机ECU是控制发动机工作的核心单元。MST12000 ECU信号模拟器能够模拟发动机实际工作时产生的各种信号。文中使用ECU信号模拟器对发动机ECU进行故障诊断,既保护了发动机,省去了ECU的安装程序,又节约了发动机工作过程中的燃油消耗。结论对于提高发动机电控系统的诊断水平和效率具有重要意义。     

基于LabVIEW的汽车电控发动机信号采集与分析系统

随着汽车电子技术的发展,对汽车电控发动机各电信号的检测愈发重要.利用虚拟仪器技术及LabVIEW软件开发平台,配以数据采集卡,实现对发动机上各传感器和执行器产生的电信号进行采集与分析.通过试验证明,这种方法能够实时准确地对发动机上各种电信号进行采集、分析及显示.     

车辆动态称重技术

随着公路运输业和商业贸易的发展，车辆动态称重技术已成为车辆载荷测量的关键技术和发展方向。文中对车辆动态称重系统的结构和弯板、压电传感器、单传感器及光纤传感器4种常用的动态称重传感器进行了介绍，并对系统产生的轴重信号进行了分析，重点讨论和研究了算术平均、神经网络、系统辨识等运用到车辆动态称重系统中的算法，并且阐述了今后的发展趋势。     

重型运输车柴油发动机电控系统研究与展望

介绍了重型运输车辆用大功率柴油机电控系统的研究现状、核心关键技术,如电子调速系统、高压共轨燃油喷射系统、废气再循环系统、冷却系统功率匹配和电子油门控制系统等,指出了重型运输车辆柴油机电控系统的发展趋势。     

OPTIMAL CONTROL APPLIED IN AUTOMATIC CLUTCH ENGAGEMENTS OF VEHICLES

Start-up working condition is the key to the research of optimal engagement of auomaticclutch for AMT. In order to guarantee an ideal dynamic performance of the clutch engagement, anoptimal controller is designed by considering throttle angle, engine speed, gear ratio, vehicle accelera-tion and road condition. The minimum value principle is also introduced to achieve an optimal dy-namic performance of the nonlinear system compromised in friction plate wear and vehicle drive qual-ity. The optimal trajectory of the clutch engagement can be described in the form of explicit and ana-lytical expressions and characterized by the deterministic and accurate control strategy in stead ofindeterministic and soft control techniques which need thousands of experiments. For validation of thecontroller, test work is carried out for the automated clutch engagements in a commercial car with antraditional mechanical transmission, a hydraulic actuator, a group of sensors and a portable computersystem. It is shown through     

基于转矩的低附路面机械式自动变速器控制策略

从机械式自动变速器控制系统所能获取的有限数据,判断行驶路面的附着系数以及车辆轮胎打滑情况,并进行驱动防滑控制;通过发动机转矩、变速器数据、整车状态等对车辆正常的加速度范围进行计算,并和轮速加速度进行比较,以确定车轮打滑情况。根据轮加速度的大小进一步判断路面附着系数。轮胎打滑时,通过对发动机的降扭和离合器的控制,实现驱动防滑的控制;在试验车辆上进行低附路面识别和控制的试验,能够正确识别出路面附着系数。在低附路面起步时,通过打滑时发动机转矩和离合器的控制,避免了车轮连续的滑转,大大提高了车辆的稳定性。这说明该低附路面识别和控制方法是可行的,能够在车上使用。     

发动机综合故障检修实训台的设计研究

随着实验(实训)设备在教育教学中的作用日益突出,各高校十分重视对其研究与开发。目前,教学实验(实训)设备正趋向智能化、微型化以及网络化的方向发展,有关汽车方面的实训设备,市面上多数的发动机实训台制造简单、价格昂贵,可进行的实训项目少之又少,而且很少具备故障检修的内容。为此,论文模拟电控发动机真实的工作原理,研发了一台可进行数十个项目实训的嵌入式智能化汽车发动机综合故障检修实训台,其既可用肉眼观察发动机各控制系统元器件的工作状况,又可用现场接线的方式学习发动机系统的结构组成和工作原理,还可进行现场实操,故障设置、排除和检修等多种功能,其性能稳定,运行良好,深受师生们的喜爱。     

Modeling and control of an electronic-vacuum booster for vehicle cruise control

A mathematical model and control laws for an Electronic-Vacuum Booster (EVB) For application to vehicle cruise control will be presented. Also this paper includes performance test result of EVB and vehicle cruise control experiments. The pressure difference between the vacuum chamber and the apply chamber is controlled by a PWM-solenoid-valve. Since the pressure at the vacuum chamber is identical to that of the engine intake manifold, the output of the electronic-vacuum booster is sensitive to engine speed. The performance characteristics of the electronic-vacuum booster have been investigated via computer simulations and vehicle tests. The mathematical model of the electronic-vacuum booster developed in this study and a two-state dynamic engine model have been used in the simulations. It has been shown by simulations and vehicle tests that the EVB-cruise control system can provide a vehicle with good distance control performance in both high speed and low speed stop and go driving situations.     

Integrated motion measurement illustrated by a cantilever beam

The combination of inertial sensors and satellite navigation receivers like those of GPS (Global Positioning System) represents a very typical integrated navigation system. Integrated navigation is the most common example of integrated motion measurement determining the translational and angular position, velocity, and acceleration of a vehicle. Traditionally, this object is assumed to be a rigid body and the signals of its closely spaced sensors are referenced to a single point of the structure. During periods of low vehicle dynamics such common navigation systems typically show stability problems due to a loss of observability of some of the motion variables.The range of applications for integrated navigation systems can be expanded due to the continuously increasing performance of data processing and cheap sensors. Further, it can be shown that the stability of such a navigation system (i. e. of the motion observer employed for the system, typically a Kalman filter) can be sustained by distributing appropriately additional sensors over the vehicle structures at distinct locations. This comprises the compensation of drift effects of the system by adding sensors that are drift-free and the guarantee of the observability of all estimated motion components. Large structures like airplanes, space stations, skyscrapers, and tower cranes with distributed sensors, however, have to take the flexibility of the structure into account. This includes an appropriate kinematical model of the structure. In this case, the theory of integrated systems has to be expanded to flexible structures. On the other hand, the additional system information obtained can be used not only for vehicle guidance but also for structural control.Within this work individual kinematical models especially of a cantilever beam, idealizing e.g. the wing of an airplane, are developed and investigated with regard to the observability of the motion variables to guarantee a stable integrated system behaviour. Finally, the application and verification of integrated measurement systems for flexible structures is shown by experiments.     

Research on an on-line wear condition monitoring system for marine diesel engine

This paper introduces a kind of on-line wear condition monitoring system for marine diesel engines. The system consists of three functions i.e. particle detecting, lubricant quality detecting and shaft torque moment and instantaneous rotation velocity detecting. The system detects wear particles in lubricant with an on-line ferrograph so as to judge wear condition of tribo-pairs of the diesel engine. A vertical detector fixed is used for environment of the marine diesel engine in this system, and the rule of distribution of particles in the vertical detector fixed and the horizontal detector fixed are alike in substance. The system detects the relative variation of lubricant quality by the grid capacitance sensors in an on-line way, which consists of an upper capacitance and a lower capacitance and can distinguish the relative variation of the dielectric constant of lubricant caused by pollutants such as water, metal particles etc. The system detects the shaft torque moment and the instantaneous rotation velocity of the diesel engine with photoelectric sensors, and corresponds the wear condition with the power condition by the change of instantaneous rotation velocity due to burning pressure change, which is helpful to judge cylinder wear.     

复合功率分流系统发动机起动模型预测控制

复合功率分流混合动力系统从纯电动模式至电子无级变速(Electronic-continuously variable transmission,E-CVT)混合动力模式的切换过程,伴随发动机的起动。由于发动机在整个起动过程始终与传动系相连,其低速往复脉动阻力矩特性对车辆模式切换过程的驾驶平顺性有直接影响,若控制不当,常引起较大的车辆纵向冲击。针对复合功率分流混合动力系统模式切换过程,基于Matlab/Simulink平台建立传动系动态模型和发动机阻力矩模型;提出一种发动机起动模型预测优化控制策略,在线计算电机转矩拖转发动机跟踪目标最优转速曲线并补偿输出端转矩波动。离线仿真及硬件在环台架试验结果表明,所开发的发动机模型预测转速跟踪控制策略能够快速起动发动机并使车辆平稳切换,将整车纵向冲击度限制在11.0m/s3以内,且对整车参数摄动具有较好的鲁棒抑制效果。