There is high potential in the hybrid drive technology for reducing fuel consumption and CO2 emissions. The use and requirements of a hybrid drive for commercial vehicles differ in many ways from the one of hybrid passenger cars. The success of hybrid solutions for commercial vehicles relies primarily on significant fuel savings, whereas energy storage and energy management play an important role.
This paper shows a simulation model which has been used for the dimensioning and detailed simulations of hybrid drive trains. To simulate the thermal effect, a co-simulation environment between longitudinal dynamics and thermal management software has been applied. The longitudinal dynamics software calculates the propulsion power which determines the thermal load of the components. Particular attention has been directed to electrical and thermal behavior of the high-traction battery. The coupling of longitudinal and
thermal simulation enables a realistic calculation of the energy use, since the effects such as the change of efficiency by temperature and load effect can be considered. This behavior also plays an important role in the development and tuning of the vehicles’ components and operating strategy.
Finally this application shows simulated data of a hybrid commercial vehicle with a lithiumion battery. For these simulations standardized driving cycles (HUDDS, JE05, …) and also cycles with a high proportion of urban driving have been simulated. These simulations show a meaningful influence on the temperature of the components, especially the battery.
For a higher hybrid market share in the future, the development of electrical components, especially energy storage systems with high power and energy densities and the reduction of system cost and weight will be essential.