Electric-Motor-in-the-Loop: Efficient Testing and Calibration of Hybrid Power Trains

Abstract New electric and hybrid vehicle propulsion architectures require the application of sophisticated control algorithms. The calibration and the validation of these control algorithms is nearly as important and time consuming as the development of the algorithms itself. Testing with the real vehicle is very expensive and only possible in late development stages. Calibration and testing tasks can be shifted to earlier phases by using precise co-simulation and Hardware-in-the-Loop approaches. This study shows the advantages of frontloading of development tasks by implementing a virtual P2-Hybrid in an Electrical-Motor-in-the-Loop test bench. As baseline, a state of the art vehicle co-simulation is used. The simulation setup is composed of a GT-Power engine model, a dSPACE vehicle dynamics model and a SimulationX power train model. This conventional model is extended by a virtual electrical motor and a hybrid control unit. With the pure Model-in-the-Loop simulation, some calibration and testing tasks are possible, but the simulation lacks of some complex physical properties, e.g. the thermal behavior of the electrical motor. In a next step, the virtual electrical motor is replaced by a real electrical motor on a test bench. The residual simulation is interacting in real-time with the real electrical motor. This enables the possibility to calibrate all relevant controllers to the real component under realistic and dynamic circumstances including mutual interaction of calibration parameter and the physical device under test.