高压共轨系统两次喷射喷油量波动规律及其组合预测模型  

Fluctuation Law of Two Injection Fuel Injection Quantity of High-Pressure Common Rail System and Its Combined Prediction Model

作　　者：屈超 费红姿[1] 魏云鹏 梁勇 郑涛 朱腾飞 QU Chao;FEI Hongzi;WEI Yunpeng;LIANG Yong;ZHENG Tao;ZHU Tengfei(School of Power and Energy Engineering, Harbin Engineering University, Harbin 150000, China)

机构地区：[1]哈尔滨工程大学动力与能源工程学院,哈尔滨150000

出　　处：《内燃机工程》2020年第6期46-54,共9页Chinese Internal Combustion Engine Engineering

基　　金：国家自然科学基金面上项目(51879059)。

摘　　要：通过对多次喷射过程的仿真分析发现喷油量波动周期与喷油器入口处第二次喷射初始压力波动的周期相同,均为1.2 ms。然后对比预主喷射和主后喷射两种喷油策略发现:当主喷脉宽达到1.4 ms时主后喷的喷油量波动曲线相位发生偏移,而预主喷射的喷油量波动曲线相位不发生偏移。最后利用BP神经网络预测模型和傅立叶逼近函数预测模型通过方差倒数法确定权值建立喷油量的组合预测模型,该组合预测模型能减少预测的系统误差,使预测结果更加精确,均方根误差仅为0.71 mg。Through a simulation analysis on multiple injections,it was found that,in the second injection,the period of injection quantity fluctuation was the same as that of the initial injection pressure fluctuation at the inlet of an injector,both were 1.2 ms.A fluctuation rate was defined to judge the severity of injection quantity fluctuation,so that the relevant laws of fuel injection quantity fluctuation were obtained.The two injection strategies of pilot-main injection and main-post injection were compared,and it was found that the injection quantity fluctuation law in the second injection changed.When the main injection pulse width reached 1.4 ms,there occurred the shift of the phase of the injection quantity fluctuation curve of the main-post injection,while the phase of the injection quantity fluctuation curve of the pilot-main injection did not shift.Finally,a combined prediction model of fuel injection quantity was established using the BP neural network prediction model and the Fourier approximation function prediction model and using the reciprocal variance method to determine the weights of the two prediction models.Results show that the combined prediction model can reduce the system error of prediction and make the prediction result more accurate,and root mean square error is only 0.71 mg.

关 键 词：多次喷射 喷油量 压力波动 组合预测模型 

分 类 号：TK421[动力工程及工程热物理—动力机械及工程]