A control design and calibration reduction methodology for AFR control in gasoline engines

作者：Rajagopalan Sai S V^*; Midlam Mohler Shawn; Yurkovich Stephen; Dudek Kenneth P; Guezennec Yann G; Meyer Jason

来源：Control Engineering Practice, 2014, 27: 42-53.

DOI：10.1016/j.conengPrac.2014.02.020

• AFR control
• Servo-mechanism
• Coordinated control
• Calibration reduction
• Linear parameter varying systems
• Offline calibration

A control architecture for air to fuel ratio (AFR) control of gasoline engines designed to work with switching and/or wide range oxygen sensors, with the goal of minimizing calibration effort while meeting performance requirements, is described. A high bandwidth, dithered inner-loop reference tracking controller with pre-catalyst oxygen sensor feedback coupled with a low bandwidth setpoint tracking outer-loop with post catalyst oxygen sensor feedback, is used to control engine exhaust and O-2 storage in the three-way catalyst (TWC), respectively. A total synthesis inspired design ensures that significant non-linearity in the system is handled through a coordinated and corrective action and expected response blocks in the open-loop, without burdening the closed loop controller. Calibration is achieved offline, through closed loop optimization using genetic algorithms, while simultaneously meeting performance and stability criteria with significantly reduced need for in-vehicle tuning. Experimental results show comparable emissions performance with the stock OEM AFR controller under warmed up conditions over a standard drive cycle.

• 出版日期2014-5