燃油喷嘴小油量非线性区补偿算法研究

随着机动车排放标准的日趋严格和不断升级,汽油直喷(gasoline direct injection, GDI)发动机需要采用更加先进而复杂的喷射模式和控制策略才能满足其要求。而先进的喷射模式和控制策略则需要控制GDI喷油器在特性曲线非线性的小油量区域进行喷射,且各喷油器特性曲线之间的离散性很大。如果从机械设计或加工工艺上提高小油量喷射的一致性,则难度很大且成本很高。基于轨压降的小油量补偿策略,通过对补偿原理与方法进行深入的研究和试验分析,成功开发和实施了GDI喷油器小油量补偿策略,并在某量产GDI喷射器上进行了补偿效果的验证。试验结果表明,进行了油量补偿后的油量一致性有较大改善,满足了GDI喷油器的小油量喷射要求。

Research on nonlinear compensation algorithm for small fuel volume of fuel nozzle

As energy?saving and emission?reduction regulations become more stringent and escala?ted,GDI engines need to adopt more advanced and complex injection modes and control strategies to meet requirements above.The advanced injection mode and control strategy need to control the GDI in?jector to inject in the small fuel quantity volume area that is rarely used.In the small fuel quantity area,the injector characteristic curve is nonlinear,and the dispersion between the injector characteristic curves is very large.It is very difficult to improve the consistency of small fuel injection from the mechanical de?sign or processing technology,and the cost is high.This paper proposes a small fuel quantity compensa?tion strategy based on rail pressure drop,and conducts in?depth research and experimental analysis on its compensation principles and methods.The small fuel quantity compensation strategy for GDI injectors has been successfully developed and implemented.The compensation effect was verified on the mass?pro?duced GDI injector,and a good compensation effect was achieved.