Thermal behavior of 48 V hybrid Systems

摘要

With regard to the current electrification of powertrains the role of 48 V hybrid systems is increasing. It offers a cost efficient possibility for a significant reduction of the fuel consumption. The Institute of Automotive Engineering developed a modular simulation model based on an optimal CO_2 operating strategy in order to compare the potential of various powertrain topologies. So far, in this simulation model thermal behavior of electric components is not taken into account. This paper describes the thermal behavior of electric components In 48 V hybrid powertrains based on simulations with an optimal CO_2 operating strategy. Therefore, different 48 V powertrain topologies with various types of electric machines are simulated first and the performance of the electric machines is varied. Furthermore, legal cycles as well as Real Driving Emissions cycles and representative customer data are used for simulation. Afterwards, for the resulting operating points the thermal behavior is simulated. Based on the results, the thermal stress is analysed and evaluated. With this, investigations if the thermal behavior and thus statements of CO_2-optimal simulation have to be evaluated critically.