Model-based design of a diesel hybrid power pack for off-highway applications

Model-based design of a diesel hybrid power pack for off-highway applications: in this master thesis , a model of parallel hybrid electric power unit (P2 architecture) has been implemented for four different off-highway applications on their respective driving cycles chosen from the American Non Regulatory Non-Road EPA: a backhoe, a crawler, an excavator and an agricultural tractor. The heavy-duty diesel engine has been hybridized to reduce NOx emissions and fuel consumption. Energy recuperation potential or hydraulics circuits for loads were not considered. After having introduced the state of the art for heavy-duty diesel engines and the main technologies to reduce pollutant emissions, it has been focused on the modeling of ICE and air path in particular through the MVEM. A possible generic model for the SCR filter was also briefly presented. In chapter 5 the main hybrid architectures have been showed, both electric and hydraulic, for heavy off-road applications, and then the chapter 6 listed the optimization techniques most used for the architectures themselves; in this analysis it has been used algorithms typical of Dynamic Programming (DP). Chapter 7 has gone more in detail about the models implemented and the simulation strategies adopted to increase the benefits of hybridization. Finally, in chapter 8 the main results of the simulations were presented and commented with a final quantitative and qualitative comparison of the types of vehicles investigated. The best results for the expected objectives were obtained by the excavator on its load profile.