Analysis and Simulation of Fuel Consumption and Energy Throughput on a Parallel Diesel-Electric Hybrid Powertrain
Examensarbete för masterexamen
The aim of this master thesis is to study the energy throughput and fuel consumption of a parallel diesel-electric hybrid vehicle. This has been done by utilising a software model of such a vehicle to simulate the results of alterations of variables believed to affect energy throughput and fuel consumption as well as other parameters of interest. These parameters are selected depending on their relative importance when it comes to hybrid technology and the power sources of such a vehicle; the diesel engine, the electric machine and also the battery. For obvious reasons it is important to focus on reducing fuel consumption but in an overall perspective it is also vital to understand how parameters related to the battery state can be affected and how the battery lifetime can be increased. Thus the key parameters in this study are energy throughput, fuel consumption, battery state of health (SOH) and state of charge (SOC), powertrain modes and drivability. Further, analyses of total used energy, costs and CO2 emissions have been made. The alterations have been made to dataset variables mainly affecting the torque distribution between the diesel engine and the electric machine and to other variables believed to affect the selected key parameters. The results show that for most variable alterations a weighting needs to be done as to the relative importance of reducing either the energy throughput or the fuel consumption since these most often change in opposite directions as the altered variables are simulated. The results can nevertheless be used as indications for how certain vehicle data alterations affect the above mentioned key parameters. It is shown that the alterations lead to reduced energy throughput more often than they lead to reductions in fuel consumption. One variable alteration however leads to decrease of both these two main key parameters, namely reduced maximum torque from the electric machine (EM). When it comes to sustainable development and CO2 emissions it can be concluded that the main source of emissions are from the diesel fuel consumption.
Elkraftteknik , Electric power engineering