Modeling and Control of a Proton Exchange Membrane Fuel Cell-Battery Power System

A general methodology of modeling, control and building a proton exchange membrane fuel cell-battery system is introduced in this thesis. A set of fuel cell-battery power system model has been developed and implemented into Simulink environment. The model is able to address the dynamic behaviours of PEM fuel cell stack, boost DC/DC converter and lithium-ion battery. In order to control the power system to achieve a proper performance, a set of system controller including a PEM fuel cell reactant supply control, a humidification controller, and a power management controller was developed based on the system model. A physical 100W PEM fuel cell-battery power system using microcontroller as embedded controller is built to validate the simulation results as well as demonstrate this new environment-friendly power source. Experimental results show that the 100W PEM fuel cell-battery power system can operates automatically with the varying load condition as a stable power supply. The experiment results follow the basic trend of the simulation results

A Novel Structure of a Direct Methanol Fuel Cell: Design, Research and Assembly

Siirretty Doriast

07041 Abstracts Collection -- Power-aware Computing Systems

From January 21, 2007 to January 26, 2007, the Dagstuhl Seminar 07041``Power-aware Computing Systems\u27\u27 was held in the International Conference and Research Center (IBFI), Schloss Dagstuhl. During the seminar, several participants presented their current research, and discussed ongoing work and open problems. This report compiles abstracts of the seminar presentations as well as the seminar results and ideas, providing hyperlinks to full papers wherever possible

E-transportation: the role of embedded systems in electric energy transfer from grid to vehicle

Electric vehicles (EVs) are a promising solution to reduce the transportation dependency on oil, as well as the environmental concerns. Realization of E-transportation relies on providing electrical energy to the EVs in an effective way. Energy storage system (ESS) technologies, including batteries and ultra-capacitors, have been significantly improved in terms of stored energy and power. Beside technology advancements, a battery management system is necessary to enhance safety, reliability and efficiency of the battery. Moreover, charging infrastructure is crucial to transfer electrical energy from the grid to the EV in an effective and reliable way. Every aspect of E-transportation is permeated by the presence of an intelligent hardware platform, which is embedded in the vehicle components, provided with the proper interfaces to address the communication, control and sensing needs. This embedded system controls the power electronics devices, negotiates with the partners in multi-agent scenarios, and performs fundamental tasks such as power flow control and battery management. The aim of this paper is to give an overview of the open challenges in E-transportation and to show the fundamental role played by embedded systems. The conclusion is that transportation electrification cannot fully be realized without the inclusion of the recent advancements in embedded systems

Classical EIS and square pattern signals comparison based on a well-known reference impedance

International audienceElectrochemical impedance spectroscopy or ac impeda nce methods are popularly used for the diagnosis of electrochemical generators (batteries or fuel cell) . It is now possible to acquire and quantitatively interpret the experimental electrical impedances of such syst ems, whose evolutions indirectly reflect the modifications of the internal electrochemical proce ss. The scope of these measurement methods is to identify the frequency response function of the sys tem under test by applying a small signal perturbat ion to the system input, and measuring the corresponding r esponse. Once identified, and according to the application, frequency response functions can provi de useful information about the characteristics of the system. Classical EIS consists in applying a set of frequency-controlled sine waves to the input of th e system. However, the most difficult problem is the integration of this type of measuring device in embedded systems. In order to overcome this problem , we propose to apply squared pattern excitation signals to perform such impedance measurements. In this paper, we quantify and compare the performance of classical EIS and the proposed broadband identif ication method applied to a well-known impedance circuit

The use of metal hydrides in fuel cell applications

This paper reviews state-of-the-art developments in hydrogen energy systems which integrate fuel cells with metal hydride-based hydrogen storage. The 187 reference papers included in this review provide an overview of all major publications in the field, as well as recent work by several of the authors of the review. The review contains four parts. The first part gives an overview of the existing types of fuel cells and outlines the potential of using metal hydride stores as a source of hydrogen fuel. The second part of the review considers the suitability and optimisation of different metal hydrides based on their energy efficient thermal integration with fuel cells. The performances of metal hydrides are considered from the viewpoint of the reversible heat driven interaction of the metal hydrides with gaseous H2. Efficiencies of hydrogen and heat exchange in hydrogen stores to control H2 charge/discharge flow rates are the focus of the third section of the review and are considered together with metal hydride-fuel cell system integration issues and the corresponding engineering solutions. Finally, the last section of the review describes specific hydrogen-fuelled systems presented in the available reference data.IS

Sustainable energy solutions for stand-alone IoT devices : Technical, environmental and economic assessment to find alternative tecnologies to power RecySmart and Single Sensor IoT devices

This work is intended to provide a high-level assessment of energy solutions to power Internet of Things (IoT) devices. The criteria for the evaluation are technical, environmental, and economic. Different technologies will be covered with support from published scientific research and the market existing solutions. The analysis will be done for a particular case study but the followed steps should serve for others looking to tackle the same issue. The intended outcome is a preselection of one or more alternatives to improve the power supply of the case study devices according to the mentioned criteria. The selection of alternatives will also include a guideline on which developments to follow and the main reasons to do so. The work is done from a business and practical perspective, meaning that after taking a first decision thanks to this work or the steps followed on it, the R&D departments of the ICT (Information and communications technologies) companies applying the methodology should then study the selected alternatives in a deeper technical analysis. In the conclusions, general next steps to carry out the development will be established. Throughout the work, it is demonstrated that there is not one single combination of technologies that is the best in all aspects, for all weathers and locations, and all applications. On the contrary, the assessment reveals how different devices and conditions affect the decision on which is the most suitable decision. In addition, there is not any alternative that has the best ranking in all aspects, as there are always technical, environmental and economical compromises. As for the specific assessment for the current status of RecySmart device (the first device of the case study), it is recommendable to follow the development towards solar photovoltaic panels in combination with Li-ion or LiPo rechargeable batteries to remove the current primary cells. The selected alternative will involve some developments but has the capability of reducing the cost of the device’s power supply by 48.9% in a 5 years period, while reducing the overall environmental impact. Thanks to the use of a solar panel and secondary cells, it is possible to eliminate 92.1% of the lithium batteries used (moving from primary to secondary cells) and ensuring the autonomy of the device. Finally, for the Single Sensor studied (the second device of the case study), the recommendation is different to the one of RecySmart, as it is more suitable to use secondary cells but without energy harvesting unit

Soft Materials for Wearable/Flexible Electrochemical Energy Conversion, Storage, and Biosensor Devices

none6Next-generation wearable technology needs portable flexible energy storage, conversion, and biosensor devices that can be worn on soft and curved surfaces. The conformal integration of these devices requires the use of soft, flexible, light materials, and substrates with similar mechanical properties as well as high performances. In this review, we have collected and discussed the remarkable research contributions of recent years, focusing the attention on the development and arrangement of soft and flexible materials (electrodes, electrolytes, substrates) that allowed traditional power sources and sensors to become viable and compatible with wearable electronics, preserving or improving their conventional performances.openBocchetta, P.; Frattini, D.; Ghosh, S.; Mohan, A.M.V.; Kumar, Y.; Kwon, Y.Bocchetta, P.; Frattini, D.; Ghosh, S.; Mohan, A. M. V.; Kumar, Y.; Kwon, Y