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In response to the need to decrease greenhouse gas emissions, the current trend in the transport sector is a greater focus on alternative powertrains. More recent air quality concerns have seen controlled zero emission zones within urban areas. As a result, there is growing interest in hydrogen fuel cell electric buses (FCEBs) as a zero local emission vehicle with superior range, operational flexibility and refuelling time than other clean alternatives e.g. battery electric buses (BEBs). This paper details the performance and suitability analysis of a proposed Wrightbus FCEB, using a quasistatic backwards-facing Simulink powertrain model. The model is validated against existing prototype vehicle data (Mk1), allowing it to be further leveraged for predictions of an advanced future production vehicle (Mk2) with next generation motors and fuel cell stack.

The bus sector is currently lagging behind when it comes to implementing autonomous systems for improved vehicle safety. However, in cities such as London, public transport strategies are changing, with requirements being made for advanced driver-assistance systems (ADAS) on buses. This study discusses the adoption of ADAS systems within the bus sector. A review of the on-road ADAS bus trials shows that passive forward collision warning (FCW) and intelligent speed assistance (ISA) systems have been successful in reducing the number of imminent pedestrian/vehicle collision events and improving speed limit compliance, respectively. Bus accident statistics for Great Britain have shown that pedestrians account for 82% of all fatalities, with three quarters occurring with frontal bus impacts.

This paper describes the development and on-vehicle validation testing of next generation parallel hybrid electric powertrain technology for use in urban buses. A forward-facing MATLAB/Simulink powertrain model was used to develop a rule-based deterministic control system for a post-transmission parallel hybrid urban bus. The control strategy targeted areas where conventional powertrains are typically less efficient, focused on improving fuel economy and emissions without boosting vehicle performance. Stored electrical energy is deployed to assist the IC engine system leading to an overall reduction in fuel consumption while maintaining vehicle performance at a level comparable with baseline conventional IC engine operation.

With a transition towards electric vehicles for the transport sector, there will be greater reliance put upon battery packs; therefore, battery pack modelling becomes crucial during the design of the vehicle. Accurate battery pack modelling allows for: the simulation of the pack and vehicle, more informed decisions made during the design process, reduced testing costs, and implementation of superior control systems. To create the battery cell model using MATLAB/Simulink, an electrical equivalent circuit model was selected due to its balance between accuracy and complexity. The model can predict the state of charge and terminal voltage from a current input. A battery string model was then developed that considered the cell-to-cell variability due to manufacturing defects. Finally, a full battery pack model was created, capable of modelling the different currents that each string experiences due to the varied internal resistance.

In this paper a dynamic, modular, 1-D vehicle model architecture is presented which seeks to enhance modelling flexibility and can be rapidly adapted to new vehicle concepts, including hybrid configurations. Interdependencies between model sub-systems are minimized. Each subsystem of the vehicle model follows a standardized signal architecture allowing subsystems to be developed, tested and validated separately from the main model and easily reintegrated. Standard dynamic equations are used to calculate the rotational speed of the desired driveline component within each subsystem i.e. dynamic calculations are carried out with respect to the component of interest. Sample simulations are presented for isolated and integrated components to demonstrate flexibility. Two vehicle test cases are presented.