FTG-S07 Modular modeling and simulation of hybrid power trains

The power train of a hybrid vehicle is considerably more complex than that of conventional vehicles. Whilst the topology of a conventional vehicle is generally fix, the arrangement of the power train components for hybrid propulsion systems is flexible. The aim is to find those configurations which are optimal for the intended use. Fuel consumption potentials can be derived with the aid of vehicle longitudinal dynamics simulation. Mostly these simulations are carried out using software which is optimized for the standard topology and do not offer the flexibility to calculate arbitrary topologies. The present thesis deals with the modular modeling and the fuel consumption simulation of complex hybrid power trains for topology analysis. A method for modeling arbitrary drive trains with high complexity is introduced. The focus lies on an efficient and fast modeling which still provides exact simulation results. Compared with standard procedures, the simulation algorithms developed are faster and more robust. As an example, the drive train of a power-split hybrid vehicle is optimized using Matlab/Simulink. With simple modification the drive train can save up to 16 percent of fuel consumption in certain driving situations.