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Electric and Hybrid-Electric buses have become a major vehicle platform for demonstrating the advantages and capabilities of electrification in heavy duty vehicles. This type of vehicle can be powered from several different sources that each have several unique operating characteristics and performance requirements that necessitate novel solutions. In this paper, a novel optimal control strategy based on the next generation range-extended electric bus (REEB) has been developed. Control strategies play an essential role in realizing the full potential of electric buses and through careful implementation can increase their effectiveness at displacing conventional internal-combustion powered buses and thus, reducing global fuel consumption and emissions. Initially, a control-oriented powertrain model was developed in Matlab/Simulink.

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.

In 2022 in the UK, the transport sector was the largest single contributing sector to greenhouse gas emissions, responsible 34% of all territorial carbon dioxide emissions [1]. In the UK there is growing uptake in zero emission powertrain technologies, with the most promising variants based on battery electric or hydrogen fuel cell electric configurations. Given the limited number of fuel cell electric buses currently in operation in Europe, vehicle models and simulations are one of the few methods available to estimate energy consumption and provide the necessary increased confidence in operating range. This paper investigates the impact of route characteristics, thermal demand and coefficient of performance of different heat source configurations on the operational energy consumption of fuel cell electric buses. Using a MATLAB/Simulink model, the total energy demand of a vehicle operating in different route/elevation profiles is considered.

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 need to decrease greenhouse gases emissions in the transport sector has resulted in the requirement for zero emission technologies in city centre bus fleets. Currently, battery electric buses are the most common choice, with both single deck and double deck vehicles in regular use. However, long-term operational capabilities are still largely unknown and unreported. Hydrogen fuel cell electric buses are an emerging zero emission technology that have the potential to complement a battery electric bus fleet where the duty cycle is challenging for current battery electric configurations. This paper compares the difference in energy consumption, for a given chassis configuration, passenger load, and heating requirement, of generic battery electric and hydrogen fuel cell electric buses operating in a typical UK city environment.