| Feedback control of a Homogeneous Charge Compression Ignition (HCCI) internal combustion engine through the aid of camshaft phasing and dual fuels is discussed in this dissertation. Control is achieved by modulating the effective compression ratio inside the combustion chamber and by varying the ratio of the input fuels; iso-octane and n-heptane. Varying the ratio of these two fuels changes the fuel octane number of the mixture, effecting the timing of combustion. Increasing the effective compression ratio increases the temperature inside the combustion chamber, advancing combustion. Proportional Integral (PI) control is implemented for the single-input single-output control problems. System identification is also applied to the engine in order to derive dynamic models between the inputs and outputs of the engine. These identified black box models are then used in the design of model based controllers. The performance of all control algorithms is validated experimentally and tested for the disturbance rejection characteristics. |
