Feedforward Model Predictive Control of Fuel-Air Ratio for Lean-Burn Spark-Ignition Gasoline Engines of Passenger Cars

Precise fuel-air ratio (FAR) control on transient conditions is one of the key technologies for lean-burn spark-ignition (SI) engines. To improve fuel economy and reduce emissions, lean-burn engines must regulate their FAR immediately under different operating conditions. The precision of FAR control is limited by the large time-varying feedback delay which is caused by mixture combustion, exhaust gas transport, and lean $N{O_{x}}$ trap (LNT) module. Hence, a FAR predictive controller is proposed to track the desired FAR value precisely in the control framework of feedforward and feedback control. First of all, a feedforward predictive model for the FAR in the cylinder and a feedback predictive model for the FAR in the exhaust pipe with a time-delay characteristic are built respectively. Next, the FAR tracking requirement and the physical actuator constraints are transformed into the optimization objective function. Finally, a feedback/embedded feedforward predictive controller is designed, and the optimization problems are solved online to obtain the fuel injection quality. The simulation results based on GT-POWER illustrate that the proposed predictive control algorithm with feedforward predictive control can track the dynamic FAR precisely in a wide range. Meanwhile, the feedback controller decreases the effects of time delay and parameters uncertainty on the system dynamics.

[1]  Jay H. Lee,et al.  Model predictive control: past, present and future , 1999 .

[2]  Karolos M. Grigoriadis,et al.  Linear parameter-varying lean burn air-fuel ratio control for a spark ignition engine , 2007 .

[3]  Xun Gong,et al.  Constrained control of free piston engine generator based on implicit reference governor , 2018, Science China Information Sciences.

[4]  John Anthony Rossiter,et al.  Feed forward design in MPC , 2009, 2009 European Control Conference (ECC).

[5]  Reza Tafreshi,et al.  Fuzzy Sliding‐mode Strategy for Air–fuel Ratio Control of Lean‐burn Spark Ignition Engines , 2018 .

[6]  Zhiyuan Liu,et al.  Fuel–air ratio control for a spark ignition engine using gain-scheduled delay-dependent approach , 2015 .

[7]  David Q. Mayne,et al.  Model predictive control: Recent developments and future promise , 2014, Autom..

[8]  Luigi del Re,et al.  Automotive model predictive control : models, methods and applications , 2010 .

[9]  Lino Guzzella,et al.  Introduction to Modeling and Control of Internal Combustion Engine Systems , 2004 .

[10]  Ansgar Trächtler,et al.  Model predictive feedforward compensation for control of multi axes hybrid kinematics on PLC , 2016, IECON 2016 - 42nd Annual Conference of the IEEE Industrial Electronics Society.

[11]  J. Karl Hedrick,et al.  Adaptive sliding mode control of air–fuel ratio in internal combustion engines , 2004 .

[12]  Tao Zou,et al.  An Offline Optimization and Online Table Look-Up Strategy of Two-Layer Model Predictive Control , 2018, IEEE Access.

[13]  Hong Chen,et al.  Triple-step method to design non-linear controller for rail pressure of gasoline direct injection engines , 2014 .

[14]  Javad Mohammadpour,et al.  Linear dynamic parameter-varying sliding manifold for air-fuel ratio control in lean-burn engines , 2013 .

[15]  Junfeng Zhang,et al.  Model Predictive Control With Mixed Performances for Uncertain Positive Systems , 2018, IEEE Access.

[16]  Javad Mohammadpour,et al.  Second-Order Sliding Mode Strategy for Air–Fuel Ratio Control of Lean-Burn SI Engines , 2014, IEEE Transactions on Control Systems Technology.

[17]  Xiaohong Jiao,et al.  ADRC‐based transient air/fuel ratio control with time‐varying transport delay consideration for gasoline engines , 2017 .

[18]  Javad Mohammadpour,et al.  A parameter-varying filtered PID strategy for air–fuel ratio control of spark ignition engines , 2012 .

[19]  Lars Eriksson,et al.  Modeling and Control of Engines and Drivelines , 2014 .

[20]  Yue Li,et al.  Study on the Effect of Fuzzy PID Air-Fuel Ratio Closed Loop Control of a Natural Gas Engine , 2014 .

[21]  Hong Chen,et al.  Automotive Control: the State of the Art and Perspective , 2013 .

[22]  A. T. Shenton,et al.  A transient virtual-AFR sensor using the in-cylinder ion current signal , 2009 .

[23]  Yujia Zhai,et al.  COMPARISON OF SINGLE-DIMENSIONAL AND MULTI-DIMENSIONAL OPTIMIZATION APPROACHES IN ADAPTIVE MODEL PREDICTIVE CONTROL FOR AIR-FUEL RATIO OF SI ENGINES , 2007 .

[24]  Graham C. Goodwin,et al.  Feedforward model predictive control , 2011, Annu. Rev. Control..

[25]  Zhijun Li,et al.  Effect of exhaust gases of Exhaust Gas Recirculation (EGR) coupling lean-burn gasoline engine on NOx purification of Lean NOx trap (LNT) , 2017 .

[26]  Reza Tafreshi,et al.  Air–fuel ratio control of lean‐burn SI engines using the LPV‐based fuzzy technique , 2018, IET Control Theory & Applications.

[27]  Reza Tafreshi,et al.  Fast predictive control for air-fuel ratio of SI engines using a nonlinear internal model , 2012 .