Two-Stage Turbocharged Gasoline Engines: Experimental Validation of Model-based Control

For increasing the efficiency of combustion engines new, increasingly complex air path concepts are viable. In case of gasoline engines one promising technology is the two-stage turbocharging. The closed-loop control of this air path concept is topic of the present paper. For this reason a model-based predictive control approach based on a piecewise affine model is investigated. It has the advantage of taking the multiple input process behavior into account, compensation for the arising dead time and respecting the turbocharger speed limits, with low demands on the calibration effort. For validating the control algorithm the investigated air path concept was installed in a vehicle and the proposed control algorithm was implemented on a prototyping control unit. In the present paper the results of the vehicle experiments, conducted on the road, are demonstrated. For validation purposes several tip-in maneuvers are demonstrated exemplary.