Electric road systems (ERS) are technologies that allow to charge electric vehicles (EVs) while they are driving. A large scale implementation of ERS would allow to significantly reduce the installed battery capacity on board the vehicles, which consequently reduces their weight and cost. Due to geographical, practical and economic constraints the ERS is not expected to cover the full extension of the road being electrified. Instead, the ERS is expected to be implemented in sections which together would cover only a fraction of the overall length of the road (). If vehicles are to perform charge sustained trips while on the electrified road, there is a tradeoff between and the required charging power. In this context, this work presents the implications of altering in the rating of the components of three alternative powertrains purposely designed to operate in conjunction with an ERS. The energy consumption and cost of the different powertrains is compared and conclusions on the effectiveness of the different configurations are drawn.

Electric road systems (ERS) are technologies that allow to charge electric vehicles (EVs) while they are driving. This makes it possible to reduce the installed battery capacity and therefore the weight and cost of the vehicle. However, while the vehicle is charging from the ERS a protective earth connection cannot be ensured, which introduces new isolation challenges in the design of the electric powertrain. This work presents, and explains the working principle of three different powertrain configurations specially designed to operate in conjunction of an ERS. These powertrain concepts differ from each other on whether or not an isolated DC-DC converter is used and in the number of traction electrical machines and converters. As case study two different applications are considered, a city bus and a heavy truck and the conclusions regarding energy consumption are cost are summarized.

Electric road systems (ERS) allows electric vehicles to charge while in motion, in turn possibly reducing the cost of the vehicle since the battery capacity can be reduced. Most conductive ERS seen today are DC and while static charging is possible from an ERS it is also often beneficial if the vehicle is able to charge from the AC grid as well. In this paper an electric powertrain with the charging functionality partially integrated in the traction components and with galvanic isolation towards the charging supply is presented and experimentally evaluated. Along with this, two other powertrain topologies with similar functionality are presented and the strengths and weaknesses of each are discussed.

An electric road system (ERS) enables transfer of electric energy to a moving vehicle, making it possible to reduce the capacity—and cost—of the battery and the need for static chargers. A conductive electric road allows for relatively low complexity whilst being able to provide high levels of power. When utilising a conductive electric road, safety precautions must be considered with regard to isolation between the charging supply (the electric road) and the vehicle’s traction voltage system (TVS), since no protective Earth connection can be guaranteed. Isolation can be achieved by separating the two systems galvanically or by double isolating the entire TVS and all equipment connected to it on-board the vehicle. This study used the experimental results from a previous paper to model and evaluate three different electric powertrains/charger topologies, including a novel integrated design fulfilling the required safety features. The models were used in a full vehicle model and further investigated in a city bus scenario in terms of how charging performance, energy consumption and battery ageing are affected by the aforementioned charging topologies and electric road characteristic. We discovered that charging topology has a strong influence on energy consumption, and that electric road characteristics have a strong influence on battery ageing.

Enabling vehicles to draw energy from an electric road system (ERS) significantly reduces the need for battery capacity on board the vehicle. It is not necessary, nor realistic, to cover every meter of every stretch of road with ERS. The question then arises how and where the ERS sections should be placed. One way of doing it is to place equally long sections of ERS with a certain separating distance. Another way is to place the sections where the highest amount of traction power of the vehicles is required. This paper presents a performance evaluation of both these methods from an energy consumption and battery degradation point of view. This study assumes a conductive ERS which allows for high power transfer. Being conductive, galvanic isolation between the energy source (the ERS) and the on board traction voltage system (TVS) is needed for electric safety reasons. In addition to the two alternative methods for location of ERS segments, three different powertrains, each with a different approach to galvanic isolation and charging, are evaluated. It is discovered that the method for location of the ERS can in fact affect both energy consumption and battery degradation depending on powertrain and driving scenario.