【作者】 程鹏；

【导师】 赵继印；

【作者基本信息】 吉林大学 ， 电子与通信工程， 2004， 硕士

【摘要】 1.课题目的和意义在进行内燃机新产品生产、开发和科学研究中,内燃机科学实验是至关重要的一个环节。而在内燃机实验中,对内燃机诸多性能参数进行准确、高精度的数据采集与分析又具有重要的地位。通过这些数据和分析结果不仅可以实现内燃机工作状况的实时监测,故障诊断,而且也可以用来评价和确认内燃机产品的优劣程度,以及是否达到预期设计的目标。本课题所研究开发的内燃机数据采集分析系统是一种便携式的并可与工业控制计算机或PC机及其兼容机进行远程通信的仪器设备。它可对内燃机动态参数进行实时监测及可对内燃机基本性能进行计算分析。对其进一步开发与完善,可适用于各种发动机的维护、维修和试验研究。并也可作为一台通用的数据采集分析系统。在地方和部队都具有一定的使用价值和应用前景,对其推广使用将产生一定的军事效益,经济效益和社会效益。2.基本的设计思想至今,国内国外已研制出许多内燃机数据采集和分析用的仪器设备,并随着微电子技术和计算机技术的迅速发展,仪器的精度和水平也不断提高,构成方式也各有不同。国外著名的产品主要有,奥地利AVL公司系列产品,如AVL640、650、670系列;日本小野公司系列产品,如CB366、CB466 467、CB566等。在使用功能方面:1.国外主要是针对测试和分析内燃机的燃烧特性为主,专业化强,实用于科学研究。其功能单一,全英文界面,软件功能少,固化后不能改变,不能加入自己的软件,再开发能力差,而价格昂贵。2.国内在模仿国外燃烧分析仪的基础上,研制出了一些适合我国国情的内燃机数据采集分析仪,但推广应用上存在问题。在系统硬件构成方面,不外可分为两大类:第一类是基于单片机的内燃机数据采集分析系统。基本框图如图1所示: <WP=97>图1 基于单片机的内燃机数据采集分析系统如AVL公司利用Motorola公司的6809及68020 CPU构成数采系统,采用500KHz/16ch/12bit的A/D板(新的AVL670系列A/D为2MHz),人机对话为终端与键盘操作方式;日本小野CB系列则采用Z80,51,96系列单片(板)机构成系统,采用250KHz/1-4ch/12bit的A/D板,人机对话主要为按键面板操作方式。第二类是基于计算机的内燃机数据采集分析系统。基本框图如图2所示:图2 基于计算机的内燃机数据采集分析系统如AVL617,日本小野新一代产品DS-9100等。国内许多科研人员或研究生都利用这种系统开发通用的或专门用途的数据采集分析系统。其价格适中,再开发能力强,适合国情。3.本课题简介3.1 系统功能设计本课题根据设计目的,在硬件上采用第一类和第二类模式相结合构成系统。即先用Intel 80C196KC单片机及MAX197 A/D等构成便携式内燃机数据采集分析仪,作为下位机,可独立完成全部设计要求的使用功能。通过RS232串行接口使便携式内燃机数据采集分析仪与工业控制计算机进行远程通信,工业控制计算机为上位机。一方面由工业控制计算机对便携式内燃机数据采集分析仪进行远程控制操作,完成数据和指令的上传下达,另一方面在工业控制计算机上对从下位机来的数据进行更进一步的处理,分析,判断和记录。 <WP=98>3.2 系统硬件基本组成根据设计要求,在硬件上采用第一类和第二类模式相结合构成系统,其硬件基本组成框图如图3所示。虚线已上为下位机硬件基本组成,虚线已下为上位机硬件基本组成。图3 内燃机数据采集分析系统硬件设计框图其中,各类传感器可测量包括气缸压力、泵端油管压力、嘴端油管压力、进气和排气管内低压波、针阀升程、气门升程、发动机冷却水进口和出口温度、机油压力和温度以及发动机气缸上止点位置,发动机转速、扭矩等。信号调整部分有电荷放大器、电压放大器、载波放大器、滤波器等,将传感器输出的信号线性地变换0~+5V之内电压信号。A/D转换器采用MAXIM公司的MAX197。A/D采样速率为100KHz,12bit,转换时间为6μs,8通道模入,各通道具有过流、过压保护功能。Intel 80C196KC系列单片机是Inter公司的16位单片机,其主频为16MHz,可寻址64KB空间,内部有16KB的EPROM/ROM,488B的RAM。具有68脚和80脚两种封装形式;显示部分采用EDM240128图形点阵式液晶显示器,其RAM显示容量为8KB,具有LED背光显示,8位并行数据接口;面板按键是通过键盘扫描方式对每个按键进行循检;通过80C196KC数据接口电路可外连接微型打印机;通过RS232串行标准实现分析仪与工业控<WP=99>制计算机进行远程通信; 80C196KC是低电平复位,采用RC电路产生上电延时;利用74LS138及GALI6V8构成地址分配设计电路,产生片选信号地址。3.3 系统软件功能设计3.3.1 系统下位机软件功能设计利用PL/M-96汇编语言对下位机进行软件功能设计,图4示出了系统下位机软件功能框图。图4 内燃机数据采集分析系统软件设计框图3.3.2 系统上位机软件功能设计利用VB高级语言编制了上位机程序。由于与下位机软件功能设计框图类似这里并没画出。3.3.3 数学模型的建立3.3.3.1 无负荷测功中平均功率测量由于J的计算误差及、n1、n2的测量误差以及发动机实验方法和状态误差,导致出现。 <WP=100>3.3.3.2 无负荷测功中瞬时功率测量3.3.3.3 曲轴扭转振动测量更多还原

【Abstract】 1.The aims and meanings of the task In the course of manufacturing and developing new type I.C. engines, I.C. engine science experiments play an important role. In the process of engines experiments, It is a momentous status that highly accuracy and precision of data acquisition and analysis for I.C. engine’s performance parameters.The measured data and analytic results not only carry out I.C. engine work status real time supervision and fault diagnosis, but also evaluate and affirm the excellent or inferior degree of I.C. engine products, and whether or not achieve anticipatory design adjective.The lower level computer system is a portable apparatus. It has tekecommunications with an industrial computer or PC. It can carry through I.C. engine dynamic parameter real time supervision, calculates and analyses I.C. engine’s basis performance.More exploration and perfected, more type I.C. engines shall be maintained, serviced, tested and researched. It can become a set of current data acquisition and analysis system too. It has certain applied value and foreground. Its popularity shall bring fairly benefit in the aspect of military affairs, economy and society. 2.Basic design idea As yet, many data acquisition and analysis systems for I.C. engine have been developed in our country and at abroad. With micro-electronics and computer technique rapid development, the apparatus’s precision and level are advanced. The equipment’s constituted manner is also different. Foreign notability products mostly have Austria AVL company series products, such as AVL640,650,670, Japan ONO SOKKI company series, such as CB366,466,566 and so on. From using functions:1) Foreign apparatus mostly aim at testing and analysis I.C. engine’s combustion trait, strongly specialization, and the upgrading are very complex. Their functions are singleness, English interface, lack software and solidified, not changed, not joining oneself software, difference again explored ability, but costliness. 2) On base of imitating foreign apparatus, our country develops some engine <WP=102>data acquisition and Analysis equipment fitting for the situation of our country, but being some problems of extending.From system hardware form, having two kinds:The first kind is based upon SCM.It was shown in Fig 1. Fig 1 I.C. engine data acquisition and analysis system based on SCMAVL company makes use of Motorola 6809 and 68020 to constitute the system, A/D conversion frequency is 500kHz/16ch/12bits. Man-machine conversation adopts terminal and keyboard handle manner. Japan ONO SOKKI CB Series adopts Z80,51,96 SCM,250 kHz/1-4ch/12bits A/D, key-press panel manner. The second kind is based on computer. It was shown in Fig 2. Fig 2 I.C. engine data acquisition and analysis system based on computerSuch as AVL617, ONO SOKKI DS-9100. Many domestic scientific research personnel or graduate students are using the kind manner to develop currency or specialties data acquisition and analysis system. Its manufacture outlay is well situated, has a new strongly explored ability, adapts to the situation of our country.3. The task brief introduction 3.1 The system functions design.We adopt combining first and second kind mode in hardware to constitute the system. Using Intel 80C196KC and MAX197 A/D constitutes lower level computer to accomplish independently those functions of design requiring .It can communicate with industrial control computer (upper level computer) via RS-232 serial interface. Upper level computer can control lower level computer in long-distance, send and receive data. Upper level computer handles, analyzes, judges and registers the data from lower level computer. <WP=103>3.2 The system hardware basic form.It was shown the hardware form in Fig 3. Upper level computer is on dashed, lower level computer under dashed. ]Fig 3 I.C. engine data acquisition and analysis system hardware des更多还原