Performance based standards for heavy vehicle combinations with electrified dolly
Ladda ner
Typ
Examensarbete för masterexamen
Master's Thesis
Master's Thesis
Program
Mobility engineering (MPMOB), MSc
Publicerad
2023
Författare
Rishi, Aakash
Modellbyggare
Tidskriftstitel
ISSN
Volymtitel
Utgivare
Sammanfattning
The need to create environmentally friendly transport solutions has guided research
in vehicle engineering over the past few decades. As a result, Battery Electric Powertrains are now in operation in small vehicles like cars. However, these solutions
often fall short in terms of providing long mission ranges and high payload capacity. Consequently, implementing them independently in Long Combination Vehicles
(LCVs) presents a challenge. This situation creates an opportunity to explore longer
and heavier High Capacity Transport (HCT) vehicles, which could reduce the number of trips required. These HCTs could potentially feature hybridized powertrains
with multiple propelling units, at least for the time being.
However, the use of multiple propelling units is likely to have an impact on vehicle
dynamics, particularly in the areas of braking stability and traction capability. This
effect could potentially lead to instability issues, such as jack-knifing. Therefore,
to ensure their compliance with street regulations, it is imperative to analyze their
performance based on the tests outlined in the Performance Based Standards (PBS)
framework.
The HELPED project has been exploring the integration of electrified dollies in Adouble HCT combinations. This thesis work falls within the scope of this project
and seeks to address several questions: How does the performance of an electrified A-double differ from that of a conventional one in terms of vehicle stability
and traction when subjected to specific PBS tests? Is the existing PBS framework
sufficient to ensure the safe operation of an electrified dolly? If necessary, what
additional tests might be required to assess and establish legislation for electrified
dolly combinations?
To address these questions, this thesis work involves modeling an A-double HCT
vehicle combination. The investigation includes modeling specific test cases to study
the traction capability and stability of the combination with and without an electrified dolly. The simulations encompass maneuvers such as Startability, Gradability,
Single Lane Change, and Deceleration in a curve. The results indicate that in terms
of traction, the electrified A-double performs significantly better than a conventional
one. However, the results from the stability simulations show that in certain conditions, such as when carrying a lighter payload on low-friction surfaces, it performs
worse when subjected to aggressive maneuvers. Hence, the implementation of an
A-double may require striking a balance between environmental efficiency and safety
considerations.
Beskrivning
Ämne/nyckelord
Battery Electric Powertrian , Performance Based Standards , Long Combination Vehicle , High Capacity Transport , HELPED , Single Lane Change