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This paper describes real-world driving tests with a battery-electric sport utility vehicle equipped with innovative chassis actuators such as high-torque in-wheel machines and a hybrid brake-by-wire (BBW) system tailored specifically for electric vehicles. In addition, the vehicle incorporates a new E/E architecture and communication bus systems to integrate the new components into the global bus network. Integrated control functions are used to investigate the potential of the new by-wire actuators to improve energy efficiency. To this end, the vehicle is tested in comparison with a series vehicle. The focus of the presented experiments is on the energy saving potential through integrated control of the subsystems for different functions such as regenerative wheel slip control or torque blending. At the end, a comparison is made between the baseline vehicle with standard centralized powertrain and friction braking system and the demonstrator with the adapted actuators to show the advantages in terms of overall efficiency and energy consumption.

In this study, different disc brakes and friction materials are evaluated with respect to particle emission output and characteristic features are derived. The measurements take place on an inertia dynamometer using a constant volume sampling system. Brake wear particle emission factors of different disc concepts in different sizes are determined and compared, using a grey cast iron disc, a tungsten carbide-coated disc and a carbon ceramic disc. The brakes were tested over a section (trip #10) novel test cycle developed from the database of the worldwide harmonized Light-Duty vehicles Test Procedure (WLTP). First, brake emission factors were determined along the bedding process using a series of trip-10 tests. The tests were performed starting from unconditioned pads, to characterize the evolution of emissions until their stabilization. In addition to number- and mass-related emission factors (PM2.5–PM10), the particle size distribution was determined. Another focus was the evaluation of temperature ranges and the associated challenges in the use of temperature readings in a potential regulation of brake wear particle emissions. The results illustrate the challenges associated with establishing a universal bedding procedure and using disc temperature measurements for the control of a representative braking procedure. Using tungsten carbide coated discs and carbon ceramic discs, emission reduction potentials of up to 70% (PM10) could be demonstrated along the WLTP brake cycle. The reduction potential is primarily the result of the high wear resistance of the disc, but is additionally influenced by the pad composition and the temperature in the friction contact area.

Um die Verzögerung von modernen Kraftfahrzeugen gewährleisten zu können, kommen üblicherweise Reibungsbremsen zur Anwendung. Dabei kommt es aufgrund tribologischer Mechanismen zu einem Verschleiß von Scheibe und Belag, was zur Emission eines partikelförmigen Bremsstaubes führt. Die emittierten Verschleißpartikel sind den Größenordnungen des Feinstaubs zuzuordnen, gelangen nahezu ungehindert in die Umwelt und stellen ein gesundheitliches Gefährdungspotential für den Menschen dar. Für die wissenschaftliche Untersuchung sind effiziente Probenahmesysteme erforderlich, welche eine qualitativ hochwertige und reproduzierbare Probe bereitstellen. In einem ersten Teil werden Erkenntnisse zum Partikelinjektions- und ausbreiteverhalten innerhalb eines Probenahmesystems für die Erfassung partikelförmiger Bremsenemissionen vorgestellt. In einem zweiten Teil werden Primär- und Sekundärmaßnahmen zur Minimierung des Feinstaubausstoßes vorgestellt und bewertet.