10,611 research outputs found

    The State of the Art in Fuel Cell Condition Monitoring and Maintenance

    Get PDF
    Fuel cell vehicles are considered to be a viable solution to problems such as carbon emissions and fuel shortages for road transport. Proton Exchange Membrane (PEM) Fuel Cells are mainly used in this purpose because they can run at low temperatures and have a simple structure. Yet to make this technology commercially viable, there are still many hurdles to overcome. Apart from the high cost of fuel cell systems, high maintenance costs and short lifecycle are two main issues need to be addressed. The main purpose of this paper is to review the issues affecting the reliability and lifespan of fuel cells and present the state of the art in fuel cell condition monitoring and maintenance. The Structure of PEM fuel cell is introduced and examples of its application in a variety of applications are presented. The fault modes including membrane flooding/drying, fuel/gas starvation, physical defects of membrane, and catalyst poisoning are listed and assessed for their impact. Then the relationship between causes, faults, symptoms and long term implications of fault conditions are summarized. Finally the state of the art in PEM fuel cell condition monitoring and maintenance is reviewed and conclusions are drawn regarding suggested maintenance strategies and the optimal structure for an integrated, cost effective condition monitoring and maintenance management system

    New business models for electric cars: A holistic approach

    Get PDF
    Climate change and global resource shortages lead to a rethinking of classic individual mobility basing on combustion engines. As a result of technological improvements first electric vehicles are introduced and further market penetrations can be expected. But due to a possible wider implementation of battery-powered electrical propulsion systems in future, new challenges arise for both the classic automotive industry and further new players, e.g. battery manufacturers, the power supply industry or other service providers. Due to the various application cases of electric vehicles discussed topically, numerous business models can emerge leading to new shares in the value creation and involving new participating players. Consequently, the individual stakeholders are uncertain as to which business models are really effective with regard to targeting a profitable overall concept. Therefore, the aim of this contribution is to define a holistic approach to developing business models for electric mobility, regarding the holistic system on the one hand and giving decision support for concerning enterprises on the other hand. For this, the basic elements of electric mobility will be observed and topical approaches for business models for various stakeholders will be discussed. The paper closes with a systemic instrument for business models basing on morphological methods. --business models,electric vehicles,morphologic box

    Urban and extra-urban hybrid vehicles: a technological review

    Get PDF
    Pollution derived from transportation systems is a worldwide, timelier issue than ever. The abatement actions of harmful substances in the air are on the agenda and they are necessary today to safeguard our welfare and that of the planet. Environmental pollution in large cities is approximately 20% due to the transportation system. In addition, private traffic contributes greatly to city pollution. Further, “vehicle operating life” is most often exceeded and vehicle emissions do not comply with European antipollution standards. It becomes mandatory to find a solution that respects the environment and, realize an appropriate transportation service to the customers. New technologies related to hybrid –electric engines are making great strides in reducing emissions, and the funds allocated by public authorities should be addressed. In addition, the use (implementation) of new technologies is also convenient from an economic point of view. In fact, by implementing the use of hybrid vehicles, fuel consumption can be reduced. The different hybrid configurations presented refer to such a series architecture, developed by the researchers and Research and Development groups. Regarding energy flows, different strategy logic or vehicle management units have been illustrated. Various configurations and vehicles were studied by simulating different driving cycles, both European approval and homologation and customer ones (typically municipal and university). The simulations have provided guidance on the optimal proposed configuration and information on the component to be used

    Transformative and Disruptive Role of Local Direct Current Power Networks in Power and Transportation Sectors

    Get PDF
    The power sector is about to undergo a major disruptive transformation. In this paper, we have discussed the best possible energy solution for addressing the challenges of climate change and eradication of energy poverty. This paper focusses on the decentralized power generation, storage and distribution through photovoltaics and lithium batteries. It encompasses the need for local direct current (DC) power through the factors driving this change. The importance of local DC power in the transportation sector is also established. Finally, we conclude with data bolstering our argument towards the paradigm shift in the power network

    Eighth National Garrett Morgan Symposium on Sustainable Transportation, Report MTI 08-03

    Get PDF
    On April 1, 2008, the Mineta Transportation Institute at San José State University hosted a videoconference that brought together experts in surface transportation and students from middle and high schools across the nation to discuss the importance of sustainable transportation. The goal was to introduce students to future career opportunities in transportation and to inspire them to take the high school and college courses that will prepare them for professional careers. Students from California, Maryland and Virginia participated in the 2008 symposium, during which they heard opening remarks from Vice Admiral Thomas J. Barrett, Deputy Secretary of the U.S. Department of Transportation. Five teams of students presented their ideas on sustainable transportation alternatives for the future. These included a magnetic hover bus that can traverse both land and water, a plug-in electric-biodiesel-solar hybrid car, applications of the Stirling engine, a solar-hydropower bus, and an electric car with back-up power from solar panels and an internal windmill. The formal presentations were followed by a moderated question-and-answer session in which student teams questioned each other about their projects and sought the advice of experts about preparation for transportation careers and the critical issues they will face in the future. This publication is an edited summary of the April 2008 event, named in honor of Garrett A. Morgan, a black American inventor honored by Congress for his contributions to transportation and public safety

    Electric Vehicle Requirements for Operation in Smart Grids

    Get PDF

    Experimental implementation controlled SPWM inverter based harmony search algorithm

    Get PDF
    An optimum PI controller using harmony search optimization algorithm (HS) is utilized in this research for the single-phase bipolar SPWM inverter. The aim of this algorithm is to avoid the conventional trial and error procedure which is usually applied in finding the PI coefficients in order to obtain the desired performance. Then, the control algorithm of the inverter prototype is experimentally implemented using the eZdsp F28355 board along with the bipolar sinusoidal pulse width modulation (SPWM) to control the output voltage drop under different load conditions. The proposed overall inverter design and the control algorithm are modelled using MATLAB environment (Simulink/m-file Code). The mean absolute error (MAE) formula is used as an objective function with the HS algorithm in finding the adaptive values of  and  parameters to minimize the error of the inverter output voltage. Based on the output results, the proposed voltage controller using HS algorithm based PI (HS-PI) showed that the inverter output performance is improved in terms of voltage amplitude, robustness, and convergence rate speed as compared to PSO algorithm based PI (PSO-PI). This is to say that the proposed controller provides a good dynamic responses in both cases; transient and steady-state. Finally, the experimental setup result of the inverter controller is verified to validate the simulation results

    Development and experimental evaluation of the control system of a hybrid fuel cell vehicle

    Get PDF
    This work presents the development and experimental evaluation of a Fuel Cell Hybrid Vehicle, focusing on the control system. The main objective of this paper is to present a real vehicle which has been designed in order to demonstrate the feasibility of the use of hydrogen as an energy source for automotive applications. The paper describes the components that are integrated in the vehicle and presents several experimental results obtained during normal operation. A control system is designed and tested in order to perform all the operations related to the coordinated operation of the fuel cell, the intermediate electrical storage and the power train. Its main task is to compute the power that must be demanded to the fuel cell in real time. This computation is done in order to satisfy the power demand of the electric motor taking into account the state of charge of the batteries and the operating regime of the fuel cell. This is accomplished by manipulating the electronic converter which regulate the current that the fuel cell supplies to the batteries.Ministerio de Ciencia y TecnologĂ­a DPI2007-66718-C04-0
    • 

    corecore