国六排放标准下的缸内直喷汽油机颗粒捕集器精度碳载模型建立及验证

Establishment and Verification of Gasoline Particulate Filters Soot Load Model Calculation for Gasoline Direct Injection Engine under China Ⅵ Emission Standard

为了验证发动机不同修正参数对发动机电子控制单元(ECU)计算汽油机颗粒捕集器(GPF)碳载量的影响,优化和改进国六标准下的汽油机颗粒捕集器控制策略。基于GPF的碳烟加载质量流量模型,利用Simulink进行建模,搭建GPF精度碳载计算仿真模型,通过发动机原排质量流量、不同工况下发动机的空燃比修正参数、PM过滤效率修正参数、发动机运行水温修正参数、发动机负荷修正参数计算模块模拟出GPF碳载量。并通过搭载一款自主研发的1.5T缸内直喷发动机进行台架和整车道路试验,对比验证了缸内直喷汽油机颗粒捕集器精度碳载模型的准确性。通过对GPF载体进行称重,可分析出发动机各修正参数对模型碳载量计算的影响效果。通过对模型进行优化,使仿真结果更接近整车表现。研究结果有利于实现GPF离线标定功能,提升GPF的控制策略,降低相应的开发成本。

In order to verify the influence of different engine correction parameters on the calculation of the carbon load of the Gasoline Particulate Filters (GPF) by the engine electronic control unit (ECU), the control strategy of the gasoline engine particle trap under China Ⅵ emission standard is optimized and improved. Based on GPF′s soot loading mass flow model, this model is modeled by Simulink, and the GPF precision carbon load calculation simulation model is built. The engine′s original mass flow rate, air-fuel ratio correction parameters of the engine under different working conditions, PM filter efficiency correction parameters, the engine operating water temperature correction parameter and the engine load correction parameter calculation module were used to simulate the GPF carbon load. And by carrying a self-developed 1.5T in-cylinder direct injection engine for bench and vehicle road test, the accuracy of the accurate carbon load model of the direct-injection gasoline engine particle trap is verified. By weighing the GPF carrier, the effect of various modified parameters of the engine on the calculation of the model carbon load can be analyzed. By optimizing the models, the simulation results are closer to the vehicle performance. The research results are beneficial to realize the GPF offline calibration function, improve the GPF control strategy, and reduce the corresponding development cost.