Spark-Ignition-Engine Idle Speed Control: An Adaptive Control Approach

The paper presents an application of a recently developed adaptive posicast controller (APC) for time-delay systems to the idle speed control (ISC) problem in spark ignition (SI) internal combustion (IC) engines. The objective is to regulate the engine speed to a prescribed set-point in the presence of accessory load torque disturbances such as those due to air conditioning and power steering. The adaptive controller, integrated with the existing proportional spark controller, is used to drive the electronic throttle actuator. We present both simulation and experimental results demonstrating the performance improvement by employing the adaptive controller. We also present the modifications and improvements to the controller structure which were developed during the course of experimentation to solve specific problems. In addition, the potential for the reduction in calibration time and effort which can be achieved with our approach is discussed.