Interactions between fuel cells and power converters influence of current harmonics on a fuel cell stack

2004 ◽  
Author(s):  
G. Fontes ◽  
C. Turpin ◽  
R. Saisset ◽  
T. Meynard ◽  
S. Astier
Keyword(s):  
Fuel Cells ◽  
Fuel Cell ◽  
Power Converters ◽  
Current Harmonics ◽  
Fuel Cell Stack

Interactions Between Fuel Cells and Power Converters: Influence of Current Harmonics on a Fuel Cell Stack

2007 ◽  
Vol 22 (2) ◽  
pp. 670-678 ◽  
Author(s):  
Guillaume Fontes ◽  
Christophe Turpin ◽  
Stphan Astier ◽  
Thierry A. Meynard
Keyword(s):  
Fuel Cells ◽  
Fuel Cell ◽  
Power Converters ◽  
Current Harmonics ◽  
Fuel Cell Stack

Overview of Field Performance by UTC Fuel Cells’ Transportation Fuel-Cell Power Plants

2005 ◽  
Author(s):  
Praveen Narasimhamurthy ◽  
Zakiul Kabir
Keyword(s):  
Fuel Cells ◽  
Fuel Cell ◽  
Power Plants ◽  
Ambient Pressure ◽  
Polymer Electrolyte Membrane ◽  
Field Performance ◽  
Pem Fuel Cell ◽  
Low Noise ◽  
Transportation Fuel ◽  
Fuel Cell Stack

UTC Fuel Cells (UTCFC) over the last few years has partnered with leading automotive and bus companies and developed Polymer Electrolyte Membrane (PEM) fuel-cell power plants for various transportation applications, for instance, automotive, buses, and auxiliary power units (APUs). These units are deployed in various parts of the globe and have been gaining field experience under both real world and laboratory environments. The longest running UTC PEM fuel cell stack in a public transport bus has accumulated over 1350 operating hours and 400 start-stop cycles. The longest running APU fuel cell stack has accrued over 3000 operating hours with more than 3200 start-stop cycles. UTCFC PEM fuel-cell systems are low noise and demonstrate excellent steady state, cyclic, and transient capabilities. These near ambient pressure, PEMFC systems operate at high electrical efficiencies at both low and rated power conditions.

Numerical Analysis of a Molten Carbonate Fuel Cell Stack in Emergency Scenarios

2020 ◽  
Vol 142 (9) ◽  
Author(s):  
Arkadiusz Szczęśniak ◽  
Jarosław Milewski ◽  
Łukasz Szabłowski ◽  
Olaf Dybiński ◽  
Kamil Futyma
Keyword(s):  
Fuel Cells ◽  
Fuel Cell ◽  
Numerical Analysis ◽  
High Accuracy ◽  
Molten Carbonate Fuel Cell ◽  
Molten Carbonate ◽  
Fuel Cell Stack ◽  
Power Load ◽  
Emergency Scenarios ◽  
Carbonate Fuel Cell

Abstract Molten carbonate fuel cells (MCFCs) offer several advantages that are attracting an increasingly intense research and development effort. Recent advances include improved materials and fabrication techniques as well as new designs, flow configurations, and applications. Several factors are holding back large-scale implementation of fuel cells, though, especially in distributed energy generation, a major one being their long response time to changing parameters. Alternative mathematical models of the molten carbonate fuel cell stack have been developed over the last decade. This study investigates a generic molten carbonate fuel cell stack with a nominal power output of 1 kWel. As daily, weekly, and monthly variations in the electrical power load are expected, there is a need to develop numerical tools to predict the unit’s performance with high accuracy. Hence, a fully physical dynamic model of an MCFC stack was developed and implemented in aspen hysys 10 modeling software to enable a predictive analysis of the dynamic response. The presented model exhibits high accuracy and accounts for thermal and electrochemical processes and parameters. The authors present a numerical analysis of an MCFC stack in emergency scenarios. Further functionality of the model, which was validated using real operational data, is discussed.

Component Failure Analysis From the U.S. Army ERDC-CERL Residential Proton Exchange Membrane Fuel Cells Demonstration

2006 ◽  
Author(s):  
Scott A. Kenner ◽  
Nicholas M. Josefik ◽  
Scott M. Lux ◽  
James L. Knight ◽  
Melissa K. White ◽  
...  
Keyword(s):  
Fuel Cells ◽  
Fuel Cell ◽  
Proton Exchange Membrane ◽  
Pem Fuel Cells ◽  
Proton Exchange ◽  
Fuel Cell Stack ◽  
The Mean ◽  
Exchange Membrane ◽  
Mean Time ◽  
The U.S

Background: The U.S. Army Engineer Research and Development Center, Construction Engineering Research Laboratory (ERDC-CERL) continues to manage The Department of Defense (DoD) Residential Proton Exchange Membrane (PEM) Fuel Cell Demonstration Project. This project was funded by the United States Congress for fiscal years 2001 through 2004. A fleet of 91 residential-scale PEM fuel cells, ranging in size from 1 to 5 kW, has been demonstrated at various U.S. DoD facilities around the world. Approach: The performance of the fuel cells has been monitored over a 12-month field demonstration period. A detailed analysis has been performed cataloging the component failures, investigating the mean time of the failures, and the mean time between failures. A discussion of the lifespan and failure modes of selected fuel cell components, based on component type, age, and usage will be provided. This analysis also addresses fuel cell stack life for both primary and back-up power systems. Several fuels were used throughout the demonstration, including natural gas, propane, and hydrogen. A distinction will be made on any variances in performance based on the input fuel stock. Summary: This analysis will provide an overview of the ERDC-CERL PEM demonstration fuel cell applications and the corresponding data from the field demonstrations. Special emphasis will be placed on the components, fuel cell stack life, and input fuel characteristics of the systems demonstrated.

Transient Analysis of Gas Distribution in the Anodic Flow Field in a Fuel Cell Stack

2013 ◽  
Author(s):  
Yasushi Ichikawa ◽  
Nobuyuki Oshima
Keyword(s):  
Fuel Cells ◽  
Fuel Cell ◽  
Flow Field ◽  
Polymer Electrolyte Fuel Cell ◽  
Gas Distribution ◽  
Fuel Cell Stack ◽  
Analysis Experiment ◽  
Hydrogen Supply ◽  
Cathodic Side ◽  
Anodic Side

In a polymer electrolyte fuel cell (PEFC), the catalyst degradation on cathodic side is one of the fatal problems caused by mal-distributed hydrogen supply into each channel on active area in a fuel cell, especially in a fuel cell stack for automotive fuel cell systems which consist of several hundreds of fuel cells stacked. For example, before getting the fuel cell system started-up, the gas in all the anodic flow passage including channels in each fuel cell is occupied by air instead of hydrogen due to cross leak from cathodic side to anodic side through the membrane employed as an electrolyte. In this situation, if hydrogen is supplied partially or unevenly between cells to start up the system, a concentration interface of air and hydrogen will be made within a fuel cell. This causes a state of local cell within a single fuel cell and the catalyst degradation (carbon corrosion or Pt dissolution) occurs. In this paper, to avoid this catalyst degradation, the gas distribution is investigated with pressurized hydrogen supply into channels located on the hundreds stacked fuel cells statically filled with air initially. A transient computational fluid analysis was applied to the flow fields of anodic side which consist of channels on fuel cells, both distributing and collecting manifold connected to the fuel cells under parameters: 1) number of stacked fuel cells (i.e. manifold length), 2) the rate of pressure rising (Pa/sec.) which makes the gas flow velocity. A gas analysis experiment was also carried out for a validation with mass spectrometer taking gas sample from several points along the gas channels on alternative fuel cells which are made of transparent acrylic resin. The results show that the uniform distribution in concentration between cells and its profile within the channels along the flow direction are strongly affected by flow field formed within the distributing manifold located upstream of stacked plates with channels.

Bipolar Plates for PEMFCs

2014 ◽  
Vol 11 (4) ◽  
Author(s):  
C. A. C. Sequeira ◽  
L. Amaral
Keyword(s):  
Fuel Cells ◽  
Fuel Cell ◽  
Manufacturing Process ◽  
High Energy ◽  
Proton Exchange ◽  
High Energy Density ◽  
Bipolar Plates ◽  
Promising Alternative ◽  
Power Sources ◽  
Fuel Cell Stack

Proton exchange membrane fuel cells (PEMFCs) have many advantages among the various types of fuel cells, such as high energy density, low temperature operation, near-zero pollution, and quick starting. Thereby, PEMFCs have been considered as the most promising alternative power sources in the transportation and stationary fields. Among the components of PEMFCs, the bipolar plates are the most representative regarding cost and volume, however, they have relevant functions on the fuel cell stack. There are about 500 bipolar plates in a PEMFC for a typical passenger car and, thus, the commercialization of the fuel cell technology becomes quite challenging. Important key aspects for a successful fuel cell stack are the design and the manufacturing process of the bipolar plate. For efficient mass production, the cycle time of the process is even more important than the material costs. It is, therefore, very important that the used material is appropriate for a fast manufacturing process. Recent developments are overcoming these issues, leading to improvements on the overall fuel cell performance and durability.

Electricity Generation From Fuel Cell Waste Heat Using an Organic Rankine Cycle

2014 ◽  
Author(s):  
Lucien Bronicki ◽  
Carl N. Nett ◽  
Josh Nordquist
Keyword(s):  
Fuel Cells ◽  
Fuel Cell ◽  
Power Plant ◽  
Waste Heat ◽  
Local Heating ◽  
Organic Rankine Cycle ◽  
Power Production ◽  
Combined Cycle ◽  
Commercial Application ◽  
Fuel Cell Stack

Fuel cells produce exhaust waste heat that can be harnessed to either meet local heating needs or produce additional electricity via an appropriately chosen bottoming cycle. Power production can often be more economically attractive than heating due to the much higher value of electricity than heat on an equivalent energy basis, especially given fuel cell incentives and subsidies that are based on the net electrical output of the (combined cycle) fuel cell power plant. In this paper we review the application of the Organic Rankin Cycle (ORC) for power production from fuel cell waste heat, with emphasis on the resulting improvements in overall power plant power output, efficiency, economics (e.g., cents/kWh maintenance costs), and emissions levels (e.g., lb/MWh emissions). We also highlight a much less obvious advantage of ORC bottoming of fuel cells; namely, its ability to partially compensate for fuel cell stack degradation over time, and corresponding potential to extend the time required between fuel cell stack overhauls. We will also review the relative difficulty of several well established commercial applications of the ORC for power production from waste heat — such as power production from gas turbine exhaust, etc. — in comparison to fuel cell applications. We conclude that not only is the ORC ideal for fuel cell bottoming, but also that fuel cells are a nearly ideal commercial application area for the ORC. In closing, we summarize a recently completed project believed to be the world’s first commercial application of ORC technology to a fuel cell power plant. This project was completed in less than a year after its initiation, and utilizes a single ORC in conjunction with five fuel cells, all located within a fuel cell park that produces nearly 15 MW of electricity.

Operation of Carbonate Fuel Cell (MCFC) Using Syngas

2011 ◽  
Author(s):  
Joseph McInerney ◽  
Hossein Ghezel-Ayagh ◽  
Robert Sanderson ◽  
Jennifer Hunt
Keyword(s):  
Power Generation ◽  
Fuel Cells ◽  
Fuel Cell ◽  
Natural Gas ◽  
High Efficiency ◽  
Cell System ◽  
System Level ◽  
Molten Carbonate ◽  
Fuel Cell Stack ◽  
Internal Reforming

High temperature fuel cells, such as Molten Carbonate Fuel Cells (MCFC), are prime candidates for power generation using natural gas. Currently MCFC-based products are available for on-site power generation using natural gas and methane-rich biogas. These systems use the most advanced stack configuration utilizing internal reforming of methane. The in-situ reforming within the fuel cell anode provides many operational benefits including stack cooling at high current densities. Syngas from a variety of sources such as coal, biomass and renewables are anticipated to play a key role in the future landscape of power generation. MCFC is capable of utilizing syngss to produce electric power at a very high efficiency. However, because of the differences in the gas compositions between natural-gas and syngas, the fuel cell stack and system designs need to be modified for syngas fuels. The purpose of this study is to develop the design modifications at both the stack and system level needed for operation of internal reforming MCFC using low-methane content syngas without major design changes from the commercial product design. The net outcome of the investigation is a fuel cell system which meets the goals of being able to operate on low methane syngas within thermo-mechanical requirements of the fuel cell stack components. In this paper, we will describe the approach for modification of MCFC design and operating parameters for operation under syngas using both system level modeling and stack level mathematical modeling.

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