Riassunto analitico
Over the last few years passenger cars have been no more the only ones undergoing strict limitations in terms of polluting emissions but also other vehicles such as trucks, buses, tractors, etc.. Indeed, there are new local and international regulations preserving the environment safety from being damaged by the so-called “Non-Road Mobile Machinery”, (NRMM). The work described in this thesis is the modelling of two hybrid architectures, a series and a parallel configuration, of a future agricultural tractor starting from a pre-existing conventional vehicle, propelled by a classic diesel engine. Like the actual model, the new one is targeted for operating in orchards and other narrow environments such as greenhouses. The simulation softwares MATLAB and Simulink have been employed for creating the two systems reproducing the powertrain of the tractor. All of this has been carried out looking at the results obtained by testing numerous implements operating in an open field. The purposes of this study have been: • hybrid architecture selection; • electric motors and engine sizing; • battery pack sizing; • strategy definition. These elements have been defined keeping in mind that, even though the tractor has a hybrid configuration, the all-electric range is a key factor. The results have shown no significant difference in terms of all-electric range between the two architectures, but a decisive point has been the room available on the vehicle for the powertrain components. Being the series configuration more space-saving, at the end of the study this was the one selected. The activity has been developed in the E-lab of HPE COXA s.r.l., an engineering consulting company based in Modena. Being commissioned by a customer, all the treated data are sensible. This is the reason why the reader of this document is only going to find a qualitative description of the work that has been accomplished.
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