Control strategy for a hydrogen combustion engine with lean and stoichiometric combustion system
摘要
Hydrogen presents a promising opportunity for the reduction of CO2 emissions in combustion processes. Due to its wide ignition limits, operation in lean mode is possible, which significantly reduces NOx emissions. However, this lean operation also leads to a reduction in the resulting torque. In contrast, stoichiometric operation increases maximum power output but leads to increased NOx emissions. In particular, a cost-effective three-way catalyst can be used in stoichiometric operation, enabling effective emission control. This investigation proposes an innovative approach that involves lean-burn operation at part load conditions and switching to stoichiometric operation at full load. The transition between these two modes has a considerable impact on overall NOx emissions. To optimize this process, new functions were developed that implement countermeasures such as lambda control, ignition timing adjustment, catalyst purging, and shortening the switching range through the use of variable valve timing and variable turbine geometry. The results show that nitrogen oxide (NOx) emissions downstream of the three-way catalyst are kept below