Scale-e-Drive

Scaling effects through modular drive architectures for commercial vehicles

The share of electric commercial vehicles, for example, almost doubled in 2018 compared with 2017, but is largely attributable to the class smaller than 3.5 tons. The 3.5 to 7-ton class is currently still based almost exclusively on combustion engines. A major reason for this is the lack of technically suitable vehicles on offer, particularly from German automakers. The hurdles are the technically demanding requirements profiles specific to commercial vehicles, the comparatively low unit numbers in economic terms, and the associated high development costs with the time problem of timely market launch. The approach in this research project is to enable the use of existing e-machines, e.g. from the passenger car sector, for light trucks. This will enable scaling effects and the timely introduction of commercial vehicles with electric drives, which is important in global competition.

However, simply applying electric drives from the passenger car sector to commercial vehicles is not sufficient here, since high power reserves would be required to meet the torque and speed requirements simultaneously, which drive up costs, volume and weight and are also disadvantageous in terms of energy. Such over-specification is to be avoided with the help of suitable transmission concepts and operating strategies that take advantage of the high dynamics of the e-machine and intelligent temperature management, so that lightweight and low-cost electric drives (including converters) such as those from the passenger car sector can also be applied energy-efficiently in the commercial vehicle sector. This results in the listed scaling effects as well as significantly reduced development costs and risks, through which the economic and time constraints can be met.

The fundamental research objective is to fully cover the highly variable and demanding vehicle dynamics requirements. The gained knowledge allows the optimization of the efficiency as well as the system weight. The results will be verified on test rigs and in a test vehicle using a prototype designed and implemented as part of the research project.

Project duration: 01.08.2020 to 31.07.2023

• Daimler Truck AG, Mercedes-Benz plant Kassel
• Department of Mechatronics with a focus on vehicles, Prof. Dr.-Ing. Michael Fister, University of Kassel
• Department of Vehicle Systems and Fundamentals of Electrical Engineering, Prof. Dr. rer. nat. Ludwig Brabetz, University of Kassel