Whereas electric drives for cars have considerable market share by now and in the truck sector, technical advances have also been made, the commercial vehicle sector between 3.5 and 7 tonnes has been overlooked. Now a research group from Kassel University has made significant progress working together with the Mercedes Benz plant in Kassel, a Daimler Truck AG site. The researchers developed a system by which proven electrical components from the passenger car area can be transferred to commercial vehicles. The research team has now presented its development.
The introduction of electric mobility in the commercial vehicle sector, for example in minibuses or delivery vans, has been difficult so far. There is a lack of suitable vehicles on offer, particularly from German car manufacturers. Obstacles include the demanding technical requirements for commercial vehicles, high development costs and comparatively low quantities.
Simply transferring electric drives from the passenger car sector to commercial vehicles doesn’t work: high power reserves would be needed to meet the simultaneous torque and speed requirements. This would increase costs, volume and weight and would be disadvantageous in terms of energy. In the project ‘Scaling effects through modular drive architectures for commercial vehicles’, or Scale-E-Drive for short, researchers solved the problem through a newly-designed two-speed gearbox and a newly-developed operating strategy that makes use of the high dynamics of the e-engine as well as intelligent temperature management.
This means that lightweight and cost-effective electric drives (including inverters) from the passenger car sector can be applied in commercial vehicles in an energy-efficient manner. This enables scaling effects as well as significantly reduced development costs and risks.
The basic research objective of the project is to fulfil the highly variable and demanding driving dynamic requirements. On the one hand, a highly dynamic shift strategy was developed to implement efficient gear change in the multi-speed transmission without any loss of comfort. Secondly, a predictive driving strategy anticipates the most energy-efficient driving strategies based on current user behaviour.
The project was funded under the Electric Mobility Funding Guideline in the amount of 1.8 million euros through the Federal Ministry for Digital and Transport (BMDV). The funding guideline is coordinated by NOW GmbH and implemented by Project Management Jülich (PtJ).
Image: A team led by Dr.-Ing. Mohamed Ayeb (Vehicle Systems and Fundamentals of Electrical Engineering), Prof. Dr.-Ing. Michael Fister (Department of Mechatronics with a focus on vehicles) and Daimler Truck AG, Kassel plant, worked together on the BMDV-funded Scale-e-Drive project. In the picture (l-r): Prof. Ayeb, Prof. Fister, Henning Rimbach (Daimler Truck), Christoph Mädler (Student at Kassel University), Prof. Ute Clement (President of Kassel University).
Source: Kassel University