基于DWT的汽油机爆震特征提取及爆震强度的判定  

DWT Based Knock Detection and Knock Intensity Judgment for a Gasoline Engine

作　　者：杨建国[1] 刘晓峰[1] 林波[1] 

机构地区：[1]哈尔滨工业大学汽车工程学院,山东威海264209

出　　处：《内燃机学报》2003年第3期233-238,共6页Transactions of Csice

摘　　要：研究了利用离散小波变换提取爆震特征的方法。利用离散小波变换不但能够有效地从汽油机缸内压力信号中提取爆震特征,而且能够有效地从缸盖上的结构振动信号中提取爆震特征。在此基础上,提出了一种基于离散小波变换的爆震强度表征方法,即利用信号经离散小波变换后在特征域上的频谱值大于参考信号在相应域上频谱值的数量作为爆震强度指标。应用和分析结果表明,对于压力信号和振动信号,这种方法均能有效地表征其爆震强度。Making use of discrete wavelet transform to extract knock feature is researched. Knock feature can be extracted effectively not only from a pressure signal measured from a cylinder in an engine, but also from a vibration signal measured from the engine cap by means of discrete wavelet transform. A kind of knock intensity based on discrete wavelet transform is presented. The numbers of the larger spectrum values of a subband signal, which is the characteristic domain of a measured signal, than that of a related reference signal is defined as the knock intensity. It is shown that the defined knock intensity can give an effective judgment for a knock from a pressure signal and even from a vibration signal.

关 键 词：汽油机 DWT 爆震特征提取 爆震强度 离散小波变换 压力信号 振动信号 

分 类 号：TK411.22[动力工程及工程热物理—动力机械及工程]