开关型废气氧传感器稳态非线性输出特性的建模研究

Modeling Study on Steady State Non-linerar Output Characteristics of a Switch-Type Exhaust Gas Oxygen Sensor

为了获得开关型废气氧(EGO)传感器的静态模型,使之可以用于发动机空燃比闭环控制系统的设计和分析。在发动机实验台上,采用比较法对EGO传感器进行了稳态标定实验。根据所得到实验数据,利用分段多项式法和非线性回归分析法建立了传感器的静态模型,并通过实验数据对模型进行了验证。研究结果表明,利用非线性回归法建立的模型具有更高的预测精度,所建模型可以作为一个静态非线性环节用于空燃比闭环控制系统的仿真研究。

In order to gain static state model of a switch-type exhaust gas oxygen sensor that could be used for the design and analysis of the engine air-fuel ratio control system, the static cahbration experiment was implemented using comparison method in an engine test-bed. The static state models of an EGO sensor were obtained by using piecewise polynomial method and nonlinear regression analysis method based on available experimental data. The model was verified by means of experimental data. The result shows that the static state model of the sensor built by nonlinear regression method is higher predictive accuracy. It can be used in simulation research of the engine air-fuel ratio control system as a static nonlinear link.