System level evaluation of diesel engine and emission after treatment systems for hybrid drivetrain applications in dynamic drive cycles
Modern, efficient combustion powertrains includes, besides the combustinengine, an exhaust aftertreatment system (EATS) to limit the emissions. In a hybrid vehicle application the combustion powertrain is complemented with e.g. an electric motor/generator and some electric energy storage capability. To obtain an efficient vehicle that minimizes fuel costs and obey legislative emission limits an overall control system is required. The efficiency of the EATS is highly dependent on the temperature in the catalysts. In the traditional, non-electrically heated, catalysts the temperature can only indirectly be influenced through the control of the combustion engine. In transient work cycles, where the combustion engine is operating at various loads, the after treatment system temperature and efficiency to reduce emissions will vary significantly. In hybrid applications, where engine shut-off is employed the situation is further pronounced. Efficient/optimal system level control strategies that explicitly accounts for the temperature effects are non-trivial for transient work cycles.
In this project an experimental investigation of the whole hybrid powertrain (including EATS) in the newly built hybrid rig at Chalmers will be performed. Data from the system will be collected to enable control oriented models to be developed and a system optimization to be done. This data collection is vital as a platform for further studies. It will enable a strong collaboration within several departments, industry and research fields.