Experimental Evaluation of VECTO Hybrid Electric Truck Simulations 2023-01-0485

In European Union (EU), new heavy-duty vehicles are simulated with the Vehicle Energy Consumption calculation TOol (VECTO) to certify their fuel consumption and CO₂ emissions. VECTO will also be used to certify vehicles with hybrid-electric powertrains in all topological configurations from P0 to P4 parallel systems and series hybrids. A development version of VECTO able to simulate these configurations is already available and was used for this study.

The study team collected measurement data from a specific P2 hybrid lorry, instrumented with wheel torque sensors, current and voltage sensors, fuel flow sensor and a PEMS device. The vehicle was tested on the chassis dyno and on the road, and a representative model was created in VECTO.

The regional delivery certification cycle was simulated in VECTO in charge sustaining and full electric mode. The results show that the development version of VECTO is able to predict the fuel consumption of the vehicle under test in charge sustaining mode with a maximum error of 6.5% and the electrical energy consumption in full electric mode with an error of 2.5%. The VECTO Hybrid Controller was evaluated by comparing the measured and simulated decisions on utilising the available power sources (fuel/stored electric energy), regenerative braking, and gear shifting. Validation simulations with gear input were run for the regional delivery, showing significant improvements for the predicted fuel and electrical energy consumption error down to 2.5% and 1.5% respectively.