Engine Idle Dynamics and Control: A 5.8L Application

An experimentally obtained low order sampled data description of the response of engine speed to throttle opening and spark advance is used to describe the idle speed dynamics of a 5.8L engine with an automatic transmission. Based upon the sampled data model, a multi-input idle speed controller is designed that returns the idle speed to its set point within five engine revolutions after the application of a load. The “cost” of control is examined and experimental data is shown for application of a sudden power steering load utilizing control of spark advance and a slow throttle actuator.