基于Hammerstein结构的电子节气门动态非线性建模

In order to realize the robust control of an electronic throttle body (ETB) system equipped with 5.7 L gasoline engine, the nonlinear inverse model of the ETB system must be established to counteract the effect of dynamic hysteresis nonlinearity on the control performance of the system. In this paper, the dynamic nonlinear characteristics of the ETB system are studied and a dynamic hysteresis model for the ETB system is proposed and identified based on the structure of Hammerstein system. It is challenging for the existing static hysteresis operators to cover the nonlinear characteristics of the ETB system. Thus, to describe the special hysteresis nonlinear characteristics of ETB system, a new static hysteresis nonlinear operator is constructed as the nonlinear subsystem for the Hammerstein model. The analytical inverse operator of the static hysteresis operator is also derived. The unmeasurable internal state in the Hammerstein system is then estimated based on the hysteresis inverse compensation strategy. Finally, the linear subsystem in the Hammerstein system is identified using the estimation method of least square. The comparison between the modeling results and experimental results shows that the proposed model can describe the dynamic hysteresis nonlinear characteristics of the ETB.