PFI汽油机空燃比控制仿真及试验研究

基于发动机台架试验,建立并标定了进气道燃油喷射单缸汽油机一维仿真模型,探索了空燃比控制的新方法。依据经典控制理论,通过所建空燃比PID控制器与参数整定,实现了稳态空燃比控制。基于x-τ油膜模型,提出了其代数控制X-Y油膜方程,分析了进气道燃油传输过程对空燃比控制的影响;通过燃油阶跃扰动法,对X,Y参数进行识别,获得了X,Y参数MAP图,构建了离散化燃油动态补偿器,实现了空燃比在瞬态工况下的前馈控制。

Simulation and Experimental Study on Air-fuel Ratio Control of PFI Gasoline Engine

Based on the engine bench test,one-dimensional simulation model of intake port fuel injection for single gasoline en-gine was built and calibrated and the control method of air-fuel ratio was explored.Steady-state AFR control was achieved by the PID controller with the built AFR and parameter identification according to the classical control theory.Based on the model of x-τ fuel film,the X-Y fuel film equation of algebraic control was proposed and the influence of fuel flow process in intake port on AFR control was analyzed.The parameters X andY were identified,the MAP of X andY was achieved,the discrete fuel dynamic compensator was constructed and the feed forward control of AFR control for transient conditions was realized by the fuel step interference method.