A Cycle Accurate Nonlinear Hybrid Model of SI Engine for the Idle Speed Control

In this document a very detailed hybrid model of a spark ignition engine in idle conditionisprovided.Themodelcollectsthenon{linearintakemanifolddynamics, the cyclic cylinders behavior, the clutch, the spark{ignition coil, the throttle valve andsensorsdynamics.Inparticular,thehybriddynamicsofeachcylindercaptures the thermodynamic behavior of the working ∞uid during each stroke of the engine cycle.Bymodellingwithwealthofdetailsthe4{strokescycle,theproposedhybrid model efiectively reproduces a sound trustworthy pulsating torque. The complete- nessofthemodelincapturingtherealsystembehaviorallowsdesignertoefiectively verifycontrolstrategies(forinstanceidle{speedcontrol).Finally,simulationresults arepresented in orderto validatethe proposed model.