【作者】 郭华锋；

【导师】 杨海青；

【作者基本信息】 南京航空航天大学 ， 车辆工程， 2007， 硕士

【摘要】 小型二冲程汽油机以其升功率大、功重比高、结构简单以及使用维护方便等优点在许多应用领域占据重要地位。但是,较高的油耗和排放问题限制了其得到更加广泛的应用。数字控制的磁电机点火系统具有能按预先设定的最佳点火提前角工作,点火时刻精确,点火范围广泛等优点,大大改善了小型二冲程汽油机的动力性、燃油经济性以及排放性。本文对以往一些点火提前角的控制方法进行了比较深入的研究,分析了各自的缺点。在此基础上,提出了点火提前角的数字控制方法。在PC机上利用NI公司的数据采集卡对点火提前角、转速、点火波形以及触发波形进行了发动机瞬态工况测量;采用单片机与PC机的RS232串行通讯技术对点火提前角和转速进行了发动机稳态工况测量。在PC机上编写了LabVIEW程序对所采数据进行显示和存储,对点火提前角进行标定,形成点火提前角的MAP图,实现点火提前角的数字控制。最后,通过试验对点火系统的测量、标定、控制方法进行了验证。结果表明,可以较准确地测量点火提前角、转速、点火波形及触发波形。本文的工作为以后的点火提前角的数字控制技术研究积累了一些经验。更多还原

【Abstract】 The small two-stroke gasoline engine has been used widely in many application areas because of its high power to weight ratio, more power per liter, simple structure and convenient maintenance. Whereas, the high fuel consumption and bad exhaust emission problem restricts it be used more widely. But the digital control of magneto ignition system can be worked according to a pre-determined optimum ignition timing, a more precisely ignition timing, a more extensively working range, it can greatly improve small two-stroke gasoline engine’s power, fuel economy and emission targets.In this paper, ignition advance angle for earlier control method were described, and the digital control of ignition advance angle was put forward based on their shortcomings analysis. The ignition advance angle, speed, ignition waveform and trigger waveform were dynamically measured by the NI collected cards. The ignition advance angle and speed were steadily measured by single chip microcomputer and RS232 communicate technology, then these parameters were displayed and storied by LabVIEW procedures. The ignition advance angles were calibrated by single chip microcomputer and LabVIEW procedures, then ignition advance angle can be control by single chip microcomputer after the ignition advance angle MAP formed.Finally, the ignition system of measure, calibration and control were tested, the ignition advance angle, speed, ignition and trigger waveform were measured, displayed and stored. The method of ignition advance angle control and its experiences were useful for subsequent work.更多还原