Saving potential of HDV auxiliaries energy consumption determined by entire vehicle simulation

Due to the decreed reduction of the exhaust emissions of motor vehicles the vehicle industry is forced to make the internal combustion engines and the auxiliaries more effective and cleaner. An essential reduction of the fuel consumption and the exhaust emissions can be realised by drive train optimisations of the auxiliaries. For the investigation of the energy consumption of conventional and innovative auxiliaries an entire vehicle simulation was developed and implemented. MatLab/Simulink was used as the simulation tool. In the simulation model the energy flows in entire motor vehicle were determined and innovative concepts of the auxiliaries were investigated. A variable drive train of each auxiliary and an uncoupling of each auxiliary from the internal combustion engine were implemented. With this setup the lowest fuel consumption of the motor vehicle can be achieved. Especially the effects of the driver and the driving cycle on the fuel consumption of the entire motor vehicle were observed. An entire vehicle simulation is developed to calculate the efficiency of the conventional motor vehicle with conventionally and innovative operated auxiliaries. Three different types of real driving cycles were measured to validate the vehicle simulation model. A comparison of the simulation and measurement results will be presented. The fuel consumption reduction of the entire vehicle was calculated and simulated using the conventionally operated and the innovative operated auxiliaries. The saving potential of the exhaust emissions and the fuel consumption will be presented and discussed.