Control oriented modeling and analysis of gas exchange and combustion processes for LTC diesel engine

Diesel low temperature combustion (LTC) has great potential for the realization of ultra low emission of internal combustion engine, which has been widely studied in recent years. Precise control of the LTC combustion is essential for the real applications of LTC concept on diesel engine. Constructing the model which can accurately describe the dynamic characteristics of diesel LTC is the foundation of the model-based controller design. In this paper, a dynamic physics based control oriented model of low temperature combustion diesel engine is presented. This model is a three-input-three-output physics-based control oriented model and consists of gas exchange sub-model and combustion sub-model. The inputs of the model are fuel rate, EGR opening rate and VGT position. The outputs are intake oxygen mass fraction, CA50 and IMEP. The model has eight states and all the states are able to be measured easily. The model is validated by a large number of steady-state and transient diesel experimental test data. The steady-state and transient validation results show that the model can accurately describe the dynamic characteristics of LTC diesel engine with high accuracy for control applications. Which lays a foundation for model-based controller design and verification of different control algorithms in LTC diesel engine.