Zero Emission Drive Unit - overview of the braking concepts

Abstract

As part of the ZEDU1 (Zero Emission Drive Unit Generation 1) project, both a conventional electric vehicle, as a reference vehicle, and a test vehicle of the Zero Emission Drive Unit, were designed for metrological characterization and tested. A central element of the project was the investigation and characterization of a cast iron and a carbide-coated brake disc in real operation as well as on a compo-nent test bench. The influence of recuperation on the braking emissions of airborne particles was also measured. The measurement results show that the temperature of the brake mainly has an influence on the generation of particles in the size range of 10 nm, whereas the braking process mainly produces particles in the size range 200 nm to 300 nm. It was also shown by measurement results that recuperation during real driv-ing, RDE cycle, can reduce airborne abrasion emissions by up to almost 90 %. A further reduction in abrasion of up to 83 % was determined for particles of size 300 nm to 10 μm for carbide-coated brake discs. In the course of the measurements, it was shown that the driving cycles used to determine the brake abrasion have a decisive influence on the measurement re-sults. In the scope of the project a novel braking system without airborne abrasion emissions was developed and validated. For this purpose, a demonstrator vehicle, as a carrier of the newly developed technology, the ZEDU1 unit, was designed, constructed, built, measured and examined for its suitability for everyday use. Suitable methods and measurement concepts for on-board characterization have also been developed and successfully implemented in use. Furthermore, the full functionality as well as fatigue strength and thus suitabil-ity for everyday use were confirmed for the developed multi-disc brake