基于小波分析和时序分析的柴油机气缸压力识别

运用小波分析方法分析研究了柴油机缸盖振动信号的时频特性，较为详细地讨论了柴油机缸盖系统的激励源及其振动响应。用小波包分析方法对振动信号及气缸压力信号进行了有效的信噪分离，并依此利用时间序列分析方法对缸盖振动信号和气缸压力信号分别建立时序模型，求取缸盖振动系统的传递函数，再利用Ｐｏｗｅｌ算法对传递函数的参数进行优化处理，然后利用缸盖表面的振动信号识别气缸压力。

Identification of Diesel Cylinder Pressure Based on Wavelet Analysis and Time-Series Analysis

The characteristic of vibration,which is acquired from the diesel engine cylinder head,is analysed by means of wavelet analysis in this paper.The excitation and the vibration response of cylinder head are also analysed in detail.Then the signal,which responds to cylinder pressure,is effectively separated from the cylinder head vibration by using wavelet packet analysis method.Based on the time series method,the model of cylinder head vibration and the model of cylinder pressure are built respectively.Finally,the transfer function of cylinder head is obtained from the models above,and the cylinder pressure is reconstructed by using the acceleration of cylinder head.In order to get more accurate transfer function,the Powell algorithm is applied in this paper to optimize the parameters of transfer function.