二冲程汽油机燃油喷射标定系统的研究.pdf

南京航空航天大学硕士学位论文 I 摘 要 为了使电控汽油机获得良好的动力性经济性和排放性能在汽油机电控系统的研究开发中需要对发动机的电控单元与发动机进行匹配对控制参数进行标定和优化这些都需要借助标定系统才能实现 本文在研究国内外电控发动机标定系统的基础上结合课题的实际情况设计了标定系统的主要功能部分该系统以动力性为主要优化目标具有修改功能能够满足研究发动机电控系统的需要标定系统 PC 机软件基于Windows平台采用 MFC 编写有独特的数据形式和通信协议具有良好的扩展性和适应性 本系统由试验用电控单元 ECU通信单元PC 机软件等几部分组成重点对通信单元和 PC 机软件进行了设计PC 机软件将 MFCMATLAB 和EXCEL有机的结合在一起 充分发挥出各自的优点 使标定系统的程序简洁灵活并给后续的数据处理带来很大的方便PC 上位机和开发用 ECU 之间的数据传输采用串行通信方式能够满足发动机稳态标定的需要 最后对标定系统进行了严格的测试并进行了喷油台试验试验结果表明本文所设计的标定系统具有良好的稳定性可靠性和扩展性能够完成标定系统的主要功能为将来的电控系统的研究提供了一个基本的试验平台 关键词电控单元标定系统通信单元MFCMATLAB 二冲程汽油机燃油喷射标定系统的研究 II ABSTRACT To improve the power and economy performance and reduce the exhaust of the electronic gasoline engine, a large amount of matching experiments between electronic control unit and engine should be done, and the control parameters should be calibrated and optimized. To finish this work, a calibration system is needed. Based on studies of the calibration system of electronic control engines and the fact of the project, the core part of the calibration system is designed. This calibration system which could modify the control parameters on-line and consider the power performance as the primary optimized aim could meet the needs of the project. Based on the Windows platform and MFC, the calibration system has particular data construction and communication protocol, and it has good expansibility and adaptability. The calibration system is composed of ECU, communication unit and PC software. The design of the communication unit and the PC software is the pivot of this paper. The software of PC make MFC, MATLAB and EXCEL combine organically, and make their advantages exert adequately. All of this make the program of the calibration system terse and flexible, and simplify the later data processing. The serial communication which is adopted between the PC and the ECU could satisfy the need of the calibration system. At last, rigorous tests and fuel injection experiment is done by applying the system. The results of tests and experiments indicate the calibration system which was designed in this paper has good scalability, stability and reliability. This system has the core functions of calibration system, and provides an experimental platform for further electronic system research. Key Words: electronic control unit, calibration system, communication unit, MFC, MATLAB 二冲程汽油机燃油喷射标定系统的研究 VI 图表目录 表 2.1 发动机主要技术参数.....................................................................................7 图 2.1 电控单元 ECU的组成框图.............................................................................8 图 2.2 ECU 主控芯片 M68HCS12 ...........................................................................10 图 2.3 节气门电路原理图 ....................................................................................... 11 图 2.4 节气门输出特性曲线....................................................................................12 图 2.5 转速信号调理电路 ......................................................................................12 图 2.6 进气温度处理电路 .......................................................................................13 图 2.7 大气压力传感器输出特性............................................................................14 图 2.8 大气压力信号处理电路 ................................................................................14 图 2.9 喷油器驱动电路...........................................................................................15 图 2.10 喷油脉宽输出波形 .....................................................................................17 图 2.11 修改 MAP 图过程框图................................................................................18 表 3.1 RS-232C 接口引线信号定义分类及功能....................................................21 表 3.2 RS-232C 主要电气性能 ................................................................................22 图 3.1 串口通信接口电路 .......................................................................................23 表 3.3 通信命令表.................................................................................................25 图 4.1 一个 MFC 应用程序的结构 ..........................................................................27 图 4.2 标定系统总体结构功能图............................................................................31 图 4.3 标定平台主界面...........................................................................................31 图 4.4 通信过程结构框图 ......................................................................................33 表 4.1 ECU 发送监测数据列表...............................................................................34 图 4.5 数据监测窗口 ..............................................................................................35 图 4.6 节气门开图表盘显示....................................................................................35 图 4.7 发动机转速曲线显示....................................................................................35 图 4 . 8 喷油脉宽显示曲线 .....................................................................................36 图 4.9 MAP 图数据表格 ......................................................。