缸内直喷汽油机的自抗扰轨压跟踪控制器设计

获得期望的共轨压力是保证缸内直喷发动机(GDI)稳定工作和喷油量精确控制的一个重要前提. 本文针对缸内直喷汽油发动机轨压控制问题, 首先通过动力学分析建立了共轨燃油喷射系统的数学模型; 由于系统中存在有较强的非线性和不确定性, 采用基于模型但对模型的精确形式依赖较小的自抗扰控制技术设计轨压跟踪控制器,其中线性扩张状态观测器(ESO) 对系统存在的总扰动和不确定性进行了估计, 非线性误差反馈控制(NLSEF) 则采用反馈补偿实现扰动的抑制. 最后, 通过给定不同的参考轨压对控制器的有效性进行验证, 仿真结果表明控制性能是满意的.

Active disturbance rejection control of fuel rail pressure for gasoline direct injection engines

The desired fuel rail pressure is a very important precondition for engine stable operation and precise control of fuel injection quantity. In this paper, the rail pressure control problem of gasoline direct injection (GDI) engine is considered. Firstly, a mathematical model of fuel rail injection system is established through dynamic analysis. To deal with the highly nonlinear dynamics and the uncertainties, the active disturbance rejection control technique is applied, which requires little information of the plant, to design the rail pressure tracking controller. In this controller, a linear extended state observer (ESO) is used to estimate the unknown dynamics of the system together with the external disturbance in realtime. The estimated disturbance is compensated by the control law of nonlinear error state feedback (NLESF) controller. The effectiveness of these controllers is validated by tracking different given reference of rail pressures. Simulation results also demonstrate that controller performance is satisfactory.