Electromobility: Inductive Charging instead of Cable Clutter TU Braunschweig develops wireless charging technology for electric vehicles in delivery services
With “emil” and “emilia”, Technische Universität Braunschweig put two electric vehicle projects on the road that implement the wireless charging of batteries. In the core research area of Mobility, it is going one step further with LISA4CL: Together with the project partner INTIS GmbH, commercial vehicles are being equipped with inductive technology for the first time. A fleet test in collaboration with the Berlin logistics and IT company Fairsenden GmbH will also demonstrate that this technology can advance the electrification of delivery transport safely, reliably and economically.
No tangled cables, no plugs: inductive charging is already standard for smartphones. In the everyday life of courier, express and parcel service providers and other logistics companies, doing without cable connections for charging their electric vehicles saves time and nerves. For this reason, TU Braunschweig and INTIS GmbH are installing inductive charging technology for the first time in commercial vehicles of an inner-city logistics company in the three-year LISA4CL research project. “TU Braunschweig has a long history of experience with high-performance inductive charging. Following the successful ’emil’ buses in Braunschweig, we want to develop and test this in real life in a smaller, lighter and more cost-effective way for passenger cars and light commercial vehicles in LISA4CL,” says Professor Bernd Engel from the elenia Institute for High Voltage Technology and Energy Systems.
Comparison of wireless and conventional charging technology
Transport vehicles will be used in the fleet test with Fairsenden GmbH in Berlin. A VW e-Crafter electric vehicle will be equipped with inductive charging technology and the charging station will be prepared accordingly to enable practical testing. In order to be able to draw a comparison between inductive technology and the plug-in charging still in use, vehicles with conventional charging technology will also be operated in the fleet test. Inductive charging technology should not only be safe and reliable, but also flexible and economical for logistics companies.
The researchers in Braunschweig have set themselves further central project goals: For example, they are developing concepts that enable vehicles to be charged with a high proportion of renewable energy. At the same time, they want to use integrated charging management to prevent overloading of the local distribution networks.
To ensure that every inductively chargeable vehicle can also use every inductive charging station, the standardization of this technology is in full swing. In spring 2022, the International Electrotechnical Commission (IEC), the international standards organization, will publish further standards so that a complete series of standards for inductive charging in public spaces will then be available. The project partner INTIS is convinced that with this level of standardization, inductive charging of vehicles in public spaces could become established by 2024 at the latest.
The standards so far cover the power range from 3.6 to 11 kilowatts. Charging systems with a charging power of up to 22 kilowatts are provided for in the standards, but have not yet been fully developed with regard to their transmission coils. In the interest of further progress in standardization, LISA4CL vehicles and charging stations are to be equipped with transmission coils of the 22 kilowatts power class. This will reduce charging times and drivers will spend less time charging. In addition, more vehicles will be able to use a charging station per day.
In order to further increase the utilization of inductive charging stations in this power class, the project partners are working on the greatest possible backward compatibility of their charging technology with the power classes already considered in the standards. “For us, wireless charging is not only a technology that will make charging e-vehicles more convenient, but primarily a technology with high potential for automated charging, e.g. for autonomous driving applications. The goal of backward compatibility with already standardized systems makes LISA4CL so exciting for us,” says INTIS Managing Director Dr. Ralf Effenberger.
A wealth of experience
The two project partners can draw on many years of experience in the everyday use of inductive charging systems. With “emil” and “emilia”, the Technical University of Braunschweig previously put two electric vehicle projects on the road that implemented wireless charging of batteries. INTIS has also equipped various series-produced cars with wireless charging technology in the past, most recently a BMW i3, which has been in trouble-free operation for more than two years.
About inductive charging technology
With inductive wireless charging, two magnetic coils transmit the energy to recharge the vehicle battery. One of the coils is located under the vehicle, the other is embedded in the floor. Inductive charging stations are maintenance-free, unobtrusive and can be used almost anywhere with robust base plates. In the future, even “snack charging” would be possible. The vehicle would then casually recharge its batteries at a red light.
The Federal Ministry of Transport and Digital Infrastructure (BMVI) is funding the LISA4CL project for three years with around 1.6 million euros until April 2023. As project coordinator, TU Braunschweig will receive over 1.3 million euros, divided between the elenia elenia Institute for High Voltage Technology and Power Systems and the Institute for Electrical Machines, Traction and Drives (IMAB). In addition to the project partner INTIS GmbH, Fairsenden, the Berlin Agency for Electromobility and VW Commercial Vehicles are associated partners. The implementation of the funding guideline is coordinated by NOW National Organisation Hydrogen and Fuel Cell Technology. Project Management Jülich is acting as project management agency within the framework of this project.