Hybrid powertrain concept evaluation using optimization

This paper describes automatic evaluation of series-parallel (combined) powertrain models using optimization. The novelty with the approach is the possibility to work with non-transparent industrial vehicle models, hidden for intellectual property reasons. The contribution extends the functionality of a recently developed tool for parallel hybrids, with the ability to operate on combined powertrains. Given the user inputs, which include dynamic vehicle model and driving cycle, the tool first produces a simplified powertrain model in the form of static maps, before dynamic programming is used to find an optimal torque split that minimizes fuel consumption. The main use of the tool is to evaluate the potential of a powertrain configuration. The paper contains an illustration of the tool operation on a non-transparent industrial vehicle model. The only requirement on the model is to provide access to some general variables and that it has a torque split that can be fully controlled