为了实现HCCI汽油机闭环反馈控制,提出了一种利用爆震传感器信号提取燃烧参数的思路.在装有全可变气门系统的汽油HCCI发动机上,测取了大量HCCI工况下爆震传感器信号;应用快速傅里叶变换,用时频分析的方法,从时域和频域提取表征爆震信号强度及相位的特征量,并对它们和HCCI燃烧参数之间的相关性做了量化比对.分析表明,爆震传感器信号相位特征值与HCCI发动机燃烧相位参数之间有着很强的相关性,爆震信号起始相位与CA10的相关系数在0.9以上HCCI燃烧强度参数与爆震信号的能量参数有着较高的相关性.
In order to implement close-loop feedback control of HCCI gasoline engine,a new thought of extracting HCCI combustion parameters from knock sensor signal was presented. Based on many an experiment on HCC1 engine bench equipped with a fully variable valve actuating system,characteristic signals were extracted from the knock sensor signal with fast Fourier transform. Comparisons were made between correlations of different couple parameters standing for combustion parameters and knock characteristic signals respectively. The analysis shows that the knock sensor signal and the combustion parameters are closely related. The correlation coefficient between CA10 and the start phase of the knock signal is more than 0.9. The combustion intensity parameters of HCCI have high correlation coefficient with the knock characteristic signals representing the energy of knock signal.