1、I 空气流量信号处理系统设计 The design of air flow rate signal processing system 摘 要 空气流量计是发动机中的一个重要部分， ， 是测量发动机吸入空气量多少的传感 器，空气流量计能够把空气流量的大小转变为电信号，空气流量计将吸入的空气量 转换成的电信号送至发动机 ECU（电控单元） ，进气量的电信号被用来计算基本喷 油持续时间和基本点火提前角。 本课题的任务是为汽车发动机空气流量计设计出一套简明的信号采集系统，使 人们能够清楚的认识到空气流量计工作过程。 本设计介绍了空气流量计的工作原理，工作方式。以及根据空气流量计的原理 和硬件结构，
2、使用相应的软件进行系统编程,并加以模拟。 软件编程主要分为两部分： A/D 转换，SCI 通信。除此之外，还要编写一个用 labview 软件做出来的界面。通过 A/D 转换将空气流量计的电压信号转换为可识别的数字信号，用 SCI 通信将数据传 递给电脑。 然后用 labview 编译的界面将数据的变化显示出来。 通过模拟实验给单片 机一个模拟的变化的电压信号使空气流量计中的电压变化在界面上显示出来。 关键词：空气流量计 A/D 转换 SCI 通信 II ABSTRACT Air flow meter ，which is an important part of the engine, is
3、a measure of how much the engine intake air quantity sensor. Air flow meter takes the size of the air flow into an electrical signal, and sends it to the engine ECU (electronic control unit). Electric signal of intake air used to calculate the basic fuel injection duration and basic ignition advance
4、 angle. The task of the project is to design a concise signal acquisition system for automotive engine air flow meter so that people can clearly be acquainted with Air flow meter working process. This design describes the air flow meter works and work. And in accordance with the principles of air fl
5、ow meter and hardware architecture, use the appropriate software to do system programming, and make simulations. Software programming is divided into two parts: A / D converter, SCI communication. In addition,we also need write a interface with labview software. The A / D conversion of the air flow
6、convert a voltage signal into a digital identification signal ,and the SCI communication pass data to the computer. Then the interface compiled with labview will display the change of the data. Via Simulation experiment , giving SCM a varying voltage signal to make the chang of air flow meter in the voltage displayed in the interface . Key words: air flow meter A/D conversion SCI communication 1 目录目录 摘 要. I ABSTRACT. II 1 绪论 1 1.1 前言 .1 1.2 空气流量计系统介绍 1 1.3 空气流量计国内外的现状和趋势.2 2 硬件设计 4 2
