Future e-mobility and the change in system requirements

Autoren

Dr. Lothar Schindele, Dr. David Schütz, Dr. Gaël Le Hen, Dr. Norbert Müller, Robert Bosch GmbH

Jahr

2019

Zusammenfassung

Mobility of tomorrow is undergoing a radical change. Against the background of increasing electrification, automated driving, the connectivity of vehicles and ever stricter CO₂ regulations, not only the powertrain technologies (e.g. BEV, FCEV, ...) but also its usage profiles (e.g. robo-taxi, car sharing, ...) and thus the requirements of the vehicle components will change considerably.
The segment of fleet operated cars will gain more importance in the mobility system of the future, and fleet operators will define vehicle requirements more and more. Their increased focus on total cost of ownership (TCO) for a given and specific use case requires flexible and scalable vehicle architectures. In order to address diverging and specific use cases, new vehicle development and optimization tools have to be applied for optimized solutions on both, a vehicle architectural level, and on a component level.
The importance of an optimal component dimensioning and design becomes obvious considering the battery sizing of an EV, where under-dimensioning may prohibit the usage for a certain application and where over-dimensioning prohibits an attractive cost situation. As an exemplary application-focused vehicle design, that entered the market in 2016, StreetScooter GmbH’s motivation was to design an EV platform specifically optimized for the purpose of parcel delivery.
Optimizing a vehicle for a specific use case like the aforementioned parcel delivery will typically lead to other vehicle architectures and component designs than optimizing a vehicle for an “average” usage. An efficiency measure that is effective during a worldwide “average” vehicle usage, as it is replicated by a WLTP test condition, might show less benefit in a specific use case like parcel delivery, or vice versa.
Bosch has developed a holistic simulation tool chain, which allows to optimize an EV’s powertrain design and vehicle architecture for a specific vehicle usage. For this purpose, usage profiles (also called “use cases”) are considered in detail, which describe the usage of the respective vehicle over the entire year. All energy flows within the vehicle (e.g. mechanical, electrical and in particular thermal) are taken into account, not only during driving, but also during parking or charging phases, in order to determine annual energy consumption. This development tool chain allows to compare a wide variety of vehicle and powertrain topologies, to assess the effectiveness of efficiency measures for a specific use case, and it allows to derive component load profiles for all relevant
components.
This paper describes the methodology of the development tool chain and gives some exemplary assessments of vehicle thermal topologies and efficiency measures for a range of vehicle use cases.

Mitglieder-Login