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This paper discusses the dependency between powertrain design and automated driving. The research questions are to what extent automated driving influences the powertrain design and how energy and fuel consumption is affected in comparison to customer driving. For this investigation a concept study is carried out for a D-segment vehicle and multiple powertrain topologies, ranging from non-electrified to plug-in hybrids and battery electric vehicles. In order to answer the research questions, the used development process and the methods for optimizing the drive system are presented accordingly, taking into account all vehicle requirements, the drive system and the components and their interactions with each other. This work focuses on two automated driving functions developed at the Institute of Automotive Engineering of the Technische Universität Braunschweig. The functions are an “automated valet parking” and a “highway pilot”.

Due to the complexity and timeliness of the dual power source control system for range extended electric vehicles, a real-time predictive fuzzy energy management strategy based on speed prediction, which comprehensively takes into account the demand power of auxiliary power unit, future average speed and driving distance is proposed in this work. Firstly, to improve the topicality and accuracy of the control system, the convolutional neural network with long short-term memory neural network (CNN-LSTM) algorithm is adopted to predict the future driving speed by the speed features and adjacent speeds.

The increasingly severe energy problems and environmental pollution have imposed severe requirements on the fuel saving level of vehicles. The range extender configuration is a tandem structure that has attracted more and more researchers’ attention due to its architectural features and control methods. An intelligent APU operating point adjustment model based on PMP-GWO-Bi-LSTM is proposed in this paper to enhance adaptability to real driving conditions for the traditional optimal strategy. Firstly, a PMP model has been applied into a range extended electric vehicle model from which the optimized power distribution data under several standard driving cycles was recorded as the input to deep learning model. Secondly, a Bi-LSTM model fed by control parameters and power distribution data was established and trained using aforementioned datasets. The aim is to learning the nonlinear regression relationship model between APU control variables and power distribution.

AIR5317 establishes the foundation for developing a successful APU health management capability for any commercial or military operator, flying fixed wing aircraft or rotorcraft. This AIR provides guidance for demonstrating business value through improved dispatch reliability, fewer service interruptions, and lower maintenance costs and for satisfying Extended Operations (ETOPS) availability and compliance requirements.

This paper presents a numerical model of a Polymer Electrolyte Membrane Fuel Cell (PEMFC) system reproducing an automotive-type powertrain. The 0D model is developed in MATLAB/Simulink environment, and it incorporates all the main auxiliary components (air and hydrogen supply line, cooling circuit) as well as the PEMFC stack unit. The model includes an ageing model to estimate the PEMFC stack degradation over time, resulting in progressive efficiency loss as well as in increased auxiliary power and thermal dissipation demand. The presented model enables the estimation of both PEMFC duration and of the time-varying request of heat rejection, facilitating the selection of auxiliaries to optimize the lifelong performance. The model constitutes the backbone for the design and optimization of PEMFC systems for automotive applications, and the integration with a degradation model provides a comprehensive research tool to estimate the long-term performance and lifetime of PEMFC system.

As the United States Army strives for electrification and hybridization of tactical and combat vehicles in alignment with its Climate Strategy, it is necessary to capture all aspects of the drive cycle. One key area for consideration is the amount of time that the vehicles spend idling. Indeed, military vehicles can idle for a considerable amount of time, especially given that soldiers must keep their vehicles running to power critical electronic subsystems. Current, standardized drive cycles do not fully capture the degree that military vehicles idle. This study begins to address this gap by analyzing geo-location data collected from the National Training Center (NTC) for several different tactical vehicles including the High Mobility Multipurpose Wheeled Vehicle (HMMWV), the Bradley Fighting Vehicle, and the Abrams Main Battle Tank. This paper details the extraction, cleaning, and analysis of the geo-location data.

This SAE Information Report contains definitions for HEV, PHEV, and EV terminology. It is intended that this document be a resource for those writing other HEV, PHEV, and EV documents, specifications, standards, or recommended practices.

The port-logistic sector has a crucial role in goods transport, as the 85-90% of international trade is achieved by means of maritime routes. The latest reports from the International Maritime Organization show that the port-logistic related activities are an important source of air pollution, both for the use of large auxiliary power systems on ships, which operate during port stays, as well as for the employment of fossil fueled road vehicles for on-site operations. As a matter of fact, the most important maritime facilities are located nearby urban areas and therefore reduction of the environmental impact in ports becomes of primary importance. Thus, in the pursuit of a greener in-port mobility, a progressive replacement of fossil fuels with cleaner alternatives must be promoted. This paper presents the analysis of the performance of a hydrogenfueled plug-in fuel cell/battery hybrid vehicle for cargo-handling in roll-on and roll-off port operations.

This is a comparative experimental study on the power generation output characteristics of auxiliary power units (APUs), with different permanent magnet materials, for trucks and special vehicles applications. The efficiency of the generator, rotor speed, torque, changes in power generation output, current, and voltage were compared and analyzed with different permanent magnet materials on the rotor. The permanent magnets composed of NdFe38 and Sm2Co17 were assembled on the generator rotor (flywheel), and their output performance characteristics were compared. The experimental results showed that efficiency is slightly higher when Sm2Co17 was installed. Moreover, when power is generated at the operating condition of the APU system, comparative tests for the rotational speed of the flywheel-mounted rotor showed that the speed of the NdFe38 permanent-magnet rotor was lower by 400 rpm.

In this paper, a high-efficiency and low-cost lithium-ion battery pack active balance system is designed. It adopts a distributed structure and consists of three parts: auxiliary power module, one-way isolated DC/DC conversion module, and a battery group. The battery single cells in the battery pack are layered and divided into m battery groups in total, and each battery group is composed of n battery single cells. Each battery group is connected to an isolated DC/DC conversion module, and all the conversion modules are connected in parallel with the auxiliary power. Taking the SOC average value of the all-single cells in one battery group as the balancing variable, the auxiliary power is controlled to charge the battery group with the lower SOC average value, so that the difference of the SOC average value of all battery groups is within the set threshold range, so as to realize the active balance of each battery group.

Suppose we have two identical variable-inertia flywheels and we connect them to the inputs of a differential. The output is connected to the driveline of a vehicle. There are several types of three-element mechanical differentials (e.g. ring-gear/carrier, epicyclic, etc.). The specific type of 3-element mechanical differential is inconsequential in the following analysis except to say there are two inputs (e.g. side gears) and one output (e.g. carrier/ring-gear). What’s important is simply the relationship - For example, using the notation ‘a’ for the first side gear and ‘b’ for the second side gear and ‘c’ for the carrier, then the relationship is: c=(a+b)/2. Understand that ‘a’, ‘b’, and ‘c’ can each be an input or an output. Using the designation ‘omega’ (ω) then the relationship looks like this: ωc=(ωa+ωb)/2.

As vehicles are getting electrified and more intelligent, the energy consumption of the auxiliary system increases rapidly. The auxiliary battery acts as the backbone of the system to support the proper operation of the vehicle. It is important to ensure the auxiliary battery has enough energy to meet the basic loads regardless the vehicle is in park or running. However, the existing methods only focus on auxiliary energy management when the vehicle is in a dynamic event. To fulfill the gap, we propose an intelligent strategy that detects the low state of charge (SOC) condition, temporarily turns down the auxiliary loads based on their priorities and charges the auxiliary battery at the maximum efficiency of the auxiliary power unit. In addition, the proposed strategy allows the vehicle to get the park duration update and make intelligent decisions on charging the auxiliary battery.

This SAE Information Report contains definitions for HEV, PHEV, and EV terminology. It is intended that this document be a resource for those writing other HEV, PHEV, and EV documents, specifications, standards, or recommended practices.

The purpose of this SAE Information Report is to provide an overview of special requirements and practices in fuel cell vehicle thermal management. This document is primarily directed to fuel cell applications in motor vehicles.

Abstract This article proposes an electric vehicle (EV) onboard microgrid for battery module balancing and vehicle-to-grid (V2G) applications. The proposed microgrid is formed by an onboard photovoltaic (PV) system, a bidirectional charger, an auxiliary power module (APM), and selection switches. The system is designed to use solar energy if available for battery balancing by supporting the battery modules with low state-of-charge (SOC) during driving or charging. During charging, when the battery pack is fully charged, the PV system is disconnected from the battery and delivers the solar power to the grid. When the number of these PV-assisted EVs is big enough, they can work together as an aggregated virtual solar farm with energy storage. When there is no solar energy available, the battery management system is able to use the APM for battery management.

The growing need for a sustainable worldwide mobility is leading towards a paradigm shift in the automotive industry. The increasingly restrictive regulations on vehicle emissions are indeed driving all of the world-leading road vehicles manufacturers to redesign the concept of transportation by developing new propulsion solutions. To this aim, a gradual electrification strategy is being adopted, and several hybrid electric solutions, such as extended-range electric vehicles with reciprocating engines or fuel cells, already represent a valid alternative to conventional vehicles powered by fossil fuels. Despite their appealing features, these hybrid propulsion systems present some drawbacks, mainly related to their complex architecture, causing high overall dimensions, weight and costs, which pose some limitation in their use for small-size vehicles.

The article presents studies of the operating process of the pneumatic engine, that can be installed on small vehicles as main or auxiliary power generating system. The aim is to assess the possibility of converting an internal combustion engine into a pneumatic engine capable of moving a vehicle with a small mass in urban settings with dense traffic flows using mathematical modelling. The behaviour in the operating processes of the engine under study has been performed by the computational method and verified experimentally at the installation created in the laboratory of the ICE department in Kharkiv National Automobile and Highway University. The computational technique in question differs from the existing ones because it is based on a dynamic model of an internal combustion engine. The developed pneumatic engine was mounted on the stand for determining its power, developed torque, compressed air consumption, pressure in its cylinders and the temperature of heating the engine.

Due to the continuous electrification of vehicles, the variety of different hybrid topologies is expected to increase in the future. As the calibration of real-time capable energy management systems (EMS) is still challenging, a development framework for the EMS that is independent of the hybrid topology would simplify the overall development process of hybrid vehicles. In this paper an analytical methodology, which is used to derive a fuel-optimal, rule-based EMS for parallel hybrids, is transferred to a series topology. It is shown that the fundamental correlations can be applied universally to both parallel and series configurations. This enables the possibility to develop a real-time capable, rule-based controller for a series HEV based on maps that ensures a fuel-optimal operation. These maps provide the optimal power threshold for the activation of the auxiliary power unit and the optimal power output dependent on the driver’s power request.

New internal combustion engines (ICE) are characterized by increasing maximum efficiency, thanks to the adoption of strategies like Atkinson cycle, downsizing, cylinder deactivation, waste heat recovery and so on. However, the best performance is confined to a limited portion of the engine map. Moreover, electric driving in urban areas is an increasingly pressing request, but battery electric vehicles use cannot be easily spread, due to limited vehicle autonomy and recharging issues. Therefore, hybrid propulsion systems are under development, in order to reduce vehicle fuel consumption, by decoupling the ICE running from road load, as well as to permit energy recovery and electric driving. This paper analyses a new-patented solution for power split hybrid propulsion system with gearbox. The system comprises an auxiliary power unit, adapted to store and/or release energy, and a planetary gear set, which is interposed between the ICE and the gearbox.

This SAE Recommended Practice establishes uniform test procedures and performance requirements for the defrosting system of enclosed cab trucks, buses, and multipurpose vehicles. It is limited to a test that can be conducted on uniform test equipment in commercially available laboratory facilities. For laboratory evaluation of defroster systems, current engineering practice prescribes that an ice coating of known thickness be applied to the windshield and left- and right-hand side windows to provide more uniform and repeatable test restults, even though—under actual conditions—such a coating would necessarily be scraped off before driving. The test condition, therefore, represents a more severe condition than the actual condition, where the defroster system must merely be capable of maintaining a cleared viewing area.