宽域废气氧传感器控制器的研究与实验

宽域废气氧（universal exhaust gas oxygen,UEGO）传感器是发动机闭环空燃比控制系统中最重要的传感器之一,其结构特殊,必须由控制器控制其温度和泵电压才能正常工作。针对温控对象的非线性特性,研究了分段加热控制算法。针对泵电压控制模块被控对象的不确定性,研究了鲁棒PID控制算法。基于dSPACE实时仿真系统实现UEGO传感器控制器,并在化油器发动机台架上进行实验。实验结果表明,控制器具有良好的鲁棒性和运行性能。λ值稳态时,控制器精度良好;λ值变化时,控制器能够快速响应。

Research and experiment of controller for UEGO sensor

Universal Exhaust Gas Oxygen（UEGO） Sensor is one of the most important sensors for the close-loop air-fuel-ratio control system of automobile engine.Due to its special structure,controller is used to control sensor’s tem-perature and pump cell voltage so that UEGO sensor can work normally.Aiming at nonlinear characteristic of the tem-perature control module,a subsection heating control method is studied.Considering uncertainty of controlled object of pump cell voltage control module,a robust PID algorithm is researched.UEGO controller is implemented by means of dSPACE real time simulation system,and experiments are conducted on a carburetor engine.Experimental results show that the UEGO controller has good robustness and running performances.Its measurement accuracy is high when λ value is in steady statues,and its response speed is fast when λ value changes.