汽油机爆震在线检测系统设计与试验

Design and Test of Gasoline Online Knock Detection System

在嵌入式工控机的控制下,应用NI数据采集卡及LabVIEW软件,完成了对非共振型压电式爆震传感器和光电式转速传感器输出信号的采集及处理,实现了基于机体振动检测的汽油机爆震在线检测。完成了检测系统的软件设计,通过信号采集模块、处理模块、爆震判别模块和数据保存模块,实现了基于LabVIEW的爆震识别。对某3缸汽油机进行爆震试验,通过分析振动信号,确定了爆震特征频率范围和爆震阈值,并研究了阈值的影响因素。最后进行发动机爆震状况在线检测,试验结果表明本检测系统对发动机爆震的识别是有效的。

Under the control of the embedded industrial computer,NI data acquisition card and Lab VIEW software were used to realize the acquisition and processing of output signals of non-resonant piezoelectric knock sensor and photoelectric tachometric transducer,and hence the online detection of gasoline knock based on the body vibration detection was realized.The software design of detection system was completed and the knock detection based on Lab VIEW was realized through the signal acquisition module,processing module,knock determination module and data storage module.The knock test of a 3-cylinder gasoline engine was conducted.By analyzing the vibration signal,the characteristic frequency range and knock threshold were determined and the influencing factors of threshold were further studied.Finally,the online detection of engine knock was conducted.The test results show that the detection system can identify engine knock effectively.