基于振动信号和瞬时转速信号的HCCI燃烧相位CA10辨识

Knock Sensor Signal and Instant Speed-Based Observer of Gasoline Engine HCCI Combustion Phasing CA10

为了实现基于循环的HCCI燃烧闭环控制,提出了一种基于爆震传感器信号和瞬时转速信号的CA10(缸内燃料燃烧10%累积放热量时的曲轴转角θ10)辨识模型.在装有全可变气门系统的汽油HCCI发动机上,测取HCCI发动机各工况下爆震传感器信号和瞬时转速信号,用时频分析方法从爆震传感器信号及瞬时转速中提取表征振动信号相位信息的特征量和瞬时转速信号特征量,分析了它们和HCCI燃烧相位θ10之间关系,提出了一种计算简单,以爆震传感器和瞬时转速信号特征量为因变量的CA10辨识模型.分析表明,CA10辨识模型能比较准确地识别HCCI燃烧相位的θ10值,对于HCCI动态过程燃烧相位θ10的预测平均误差小于1.7,°CA.

In order to implement close-loop feedback control of HCCI gasoline engine, an observer model of CA10 is presented based on knock sensor signals and instant engine speed by the mathematical method of Artificial Neural Networks. Based on a great deal of experiment on HCCI engine bench equipped with a fully variable valve actuating system, analysis of and comparison between knock signal, instant speed and CA10 are made, and characteristic parameters are extracted from knock sensor signal and instant speed. Then, an observer of CA10 is built with the characteristic signals of knock sensor and instant speed, which is simple in computation and easy to be implemented on microcontroller. It is shown that the observer is capable of calculating CA 10 and the detecting average deviation of combustion phase CA10 is less than 1.7 °CA.