Experimental Analysis and Control-Oriented Modeling for Cyclic Variation of Cylinder Pressure in IC Engines

Cyclic variability control is the essential way for torque generation balance, which is an important index when engine works in the steady mode. This paper proposes an idea for indirectly balancing cyclic variability by keeping cylinder pressure of fixed crank shift degree at its nominal value. Ignition time is chosen as the actuator after sensitive analysis is executed, and the dynamics from spark advance to cylinder pressure at the given crank shift degree is modeled, parameters are identified by using least variance algorithm, an simulation for this model is established and the PI control validated by this simulation is tested by experiments too.