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Cell performances of direct methanol fuel cells with grafted membranes
06 Electrical power supply and utilization (scientific, technical) method. Next, based on experts’ estimation of elementary relations among projects over periods, mathematical formulae for covariances among projects and periods were derived. This is shown to enhance the implementability of the generation expansion planning model. Also, managerial insights are provided (e.g. a set of negatively correlated projects will reduce the financial risk associated with stranded cost). Finally, by way of a numerical example, the features of the model are illustrated. 03/00644 Aerodynamic drag of new-design electric power wire in a heavy rainfall and wind Kikuchi, N. ct al. Jourrml of Wmd Engineering and Industrlcll Aerodynumics, 2003, 9 1, ( l-2), 4 l-5 1. The authors have studied out grooved round transmission wires, developing Model LP-810 wire with lesser drag. Aerodynamic characteristic of grooved round transmission wires were studied in wind-tunnel experiments. But being located outdoors, electric power transmission facilities are subject to the design limit loading in a strong wind, which, in most cases, is based on typhoon-weather conditions. Consequently, the wind-tunnel experimentation needs to attach a factor of rainfall to the simulated wind conditions (usual wind conditions). In this laboratory test, the authors set up a watering grid upwind in the wind-tunnel’s test section, which simulated a number of rainfall: 0,2, 4, 8, 10, 16, 25 and 40 mm per 10 min. Those rainfalls were rationalized, based on the domestic weather observation data: 10 min cumulative amounts of rain and 10 min mean wind speeds of time frame. Thus, LP-810 was tested under simulated, rational wind and rainfall conditions, and its design drag coefficients were figured out. 03/00645 Alkaline fuel cells: contemporary advancement and limitations Burchardt, T. (‘1 al. Furl, 2002, 81, (lb), 2151-2155. ZeTek Power recently introduced mass manufacturable and cost effective alkaline fuel cells on the market. Today’s research is focused on further improvement both in terms of performance increase and cost reduction. This research is classically performed using small (4cm2) experimental electrodes in the half-cell configuration. This allows the primary electrochemical losses in an anode or cathode to be determined independently. Additional performance losses occur when one integrates large electrodes into a module of 24 cells and in a stack comprised of many modules. By comparing the performance of halfcell experiments to that of modules, these losses can be distinguished and addressed. The information thus obtained, both for the small electrodes and in up-scaling is vital if one is to identify the key areas in which improvement is possible and where to focus future research. Furthermore, the identification of the losses in a module and system allows us to predict the final performance from half-cell measurements of a new laboratory scale experimental electrode. 03/00646 An indirect adaptive fuzzy-logic power system stabiliser Hossein-Zadeh, N. and Kalam, A. htrrnutioncrl Journcrl of Elcc tricrrl Power & Energ\, S~~stem.~.,2002, 24. (lo), 837-842. An indirect adaptive fuzzy power system stabilizer (AFPSS) is developed using the concept of fuzzy basis functions. The power system is modelled using differential equations with non-linear parameters which are functions of the state of the system. These non-linear functions may not be known, however, some linguistic information is available about them. Utilizing this information, fuzzy logic systems are designed to model the system behaviour. The control law is obtained using the uncertainty principle. Based on the Lyapunov’s synthesis method, adaptation rules are developed to make the controller adaptive to changes in operating conditions of the power system. The simulation studies are carried out for an industrial cogenerator and utilize a one-machine infinite-bus model. Non-linear simulations reveal that the performance of AFPSS is better than the performance of a conventional (linear) power system stabilizer for a wide range of operating conditions.
proposed technique is demonstrated (21-line) test systems. Computation potential candidate for inclusion analysis package.
on 5-bus (7-line) and 1EEE 14-bus efficiency of the method makes it in on-line comprehensive security
Carbon monoxide adsorption for carbon 03/00646 monoxide removal in a fuel cell system Gittleman, C. S. et al. U.S. Pat. Appl. Publ. US 2002 110,504 (Cl. 422190; BOlD53/62), I5 Aug 2002, Appl. 780,184, 9 Feb 2001. 12. An apparatus removes carbon monoxide (CO) from a hydrogen-rich gas stream in a hydrogen fuel cell system. CO fouls costly catalytic particles in the membrane electrode assemblies of proton exchange membrane (PEM) fuel cells. A vessel houses a carbon monoxide adsorbent. The vessel may be a rotating pressure swing adsorber. A water gas shift reactor is upstream of the rotatin!; pressure swing adsorber. The water gas shift reactor may include a c;econd adsorbent adapted to adsorb carbon monoxide at low temperatures and to desorb carbon monoxide at high temperatures. The apparatus advantageously eliminates the use of a preferential oxidation (PROX) reactor, by providing an apparatus that incorporates CO adsorptilon in the place of the PROX reactor. This cleans up carbon monoxide without hydrogen consumption and the concomitant, undesirable exce’.s low-grade heat generation. The invention reduces start-up duration, and improves overall fuel processor efficiency during normal operz’tion. 03/00649 Cell performances of direct methanol fuel cells with grafted membranes Hatanaka, T. et rd. Furl, 2002, 81, (17), 2173 2170. Cell performances were evaluated with grafted polymer membranes as an electrolyte for a direct methanol fuel cell (DMFC) The membranes were prepared using a poly(ethylene-tetrafluoroethylene), or ETFE, film. The base polymer film was added to sulfonic groups using yradiation activated grafting technique as ion-exchange groups. These membranes had more suitable properties for DMFCs, i.e. higher electric conductivity and lower methanol permeability than perfluorinated ionomer membrane (Nafion). Nevertheless, the cell performance with the grafted membrane was inferior to that with Nafion. The analysis of electrode potentials vs. reversible hytlrogen electrode showed larger activation overpotential for both the electrodes on the grafted membranes. It was concluded that this is due to poor bonding of the catalyst layers to the grafted membranes. 03/00650 Combined water gas shift reactor/carbon dioxide absorber for use in a fuel cell system Gittleman, C. S. and Gupta, R. U.S. Pat. Appl. Publ. US 2002 110,503 (Cl. 422-190; BOlD53/62), 15 Aug 2002, Appl. 780,079, 9 Feb 2001. 14. An apparatus removes CO from a hydrogen-rich gas stream in a hydrogen fuel cell system. CO fouls costly catalytic particles in the membrane electrode assemblies. Both a catalyst adapted to perform a water gas shift reaction, and a carbon dioxide adsorbent are disposed in a rotating pressure swing adsorber housing. The adsorption of carbon dioxide shifts equillibrium toward carbon monoxide consumption. A second adsorbent may be disposed in the housing for adsorbing carbon monoxide at low temperatures, and is adapted to desorb carbon monoxide at high temperatures. The present invention advantageously eliminates a unit operation from a space-constrained fuel cell vehicle by combining the WGS catalyst and a CO? adsorbent in a single reactor/housing. The apparatus further eliminates the: use of a PROX reactor, by providing an apparatus which incorporate*, CO?_ adsorption and consequent carbon monoxide consumption in the place of the PROX reactor.
03/00647 ANN for transmission system static security assessment Chauhan, S. and Dave, M. P. Irrtrtxntional Journal of Electricul Po\l’rr & Erzerg~~Sy.\terns, 2002, 24. (II)). 8677873. This paper presents computationally efficient artificial neural network technique for assessing the security of the power system against line outages. Performance index (PI), which accounts for various line limit violations per contingency, is defined. The basic purpose of artificial neural networks (ANN) is to assess the severity of line outages in terms of PI, based on training examples from off-line analysis. The selection of input signals for ANN is influenced by the operating state of the cystem and the contingency in question that determines the extent of line power limit violations. In an attempt to attain perfection in PI prediction, suitable architecture and topology for the network is investigated. To expedite learning process, saturating linear coupled neuron model (sl-CONE) i< also tried out. The effectiveness of
Fuel and Energy Abstracts
May 2003
153
proposed technique is demonstrated (21-line) test systems. Computation potential candidate for inclusion analysis package.
on 5-bus (7-line) and 1EEE 14-bus efficiency of the method makes it in on-line comprehensive security
Carbon monoxide adsorption for carbon 03/00646 monoxide removal in a fuel cell system Gittleman, C. S. et al. U.S. Pat. Appl. Publ. US 2002 110,504 (Cl. 422190; BOlD53/62), I5 Aug 2002, Appl. 780,184, 9 Feb 2001. 12. An apparatus removes carbon monoxide (CO) from a hydrogen-rich gas stream in a hydrogen fuel cell system. CO fouls costly catalytic particles in the membrane electrode assemblies of proton exchange membrane (PEM) fuel cells. A vessel houses a carbon monoxide adsorbent. The vessel may be a rotating pressure swing adsorber. A water gas shift reactor is upstream of the rotatin!; pressure swing adsorber. The water gas shift reactor may include a c;econd adsorbent adapted to adsorb carbon monoxide at low temperatures and to desorb carbon monoxide at high temperatures. The apparatus advantageously eliminates the use of a preferential oxidation (PROX) reactor, by providing an apparatus that incorporates CO adsorptilon in the place of the PROX reactor. This cleans up carbon monoxide without hydrogen consumption and the concomitant, undesirable exce’.s low-grade heat generation. The invention reduces start-up duration, and improves overall fuel processor efficiency during normal operz’tion. 03/00649 Cell performances of direct methanol fuel cells with grafted membranes Hatanaka, T. et rd. Furl, 2002, 81, (17), 2173 2170. Cell performances were evaluated with grafted polymer membranes as an electrolyte for a direct methanol fuel cell (DMFC) The membranes were prepared using a poly(ethylene-tetrafluoroethylene), or ETFE, film. The base polymer film was added to sulfonic groups using yradiation activated grafting technique as ion-exchange groups. These membranes had more suitable properties for DMFCs, i.e. higher electric conductivity and lower methanol permeability than perfluorinated ionomer membrane (Nafion). Nevertheless, the cell performance with the grafted membrane was inferior to that with Nafion. The analysis of electrode potentials vs. reversible hytlrogen electrode showed larger activation overpotential for both the electrodes on the grafted membranes. It was concluded that this is due to poor bonding of the catalyst layers to the grafted membranes. 03/00650 Combined water gas shift reactor/carbon dioxide absorber for use in a fuel cell system Gittleman, C. S. and Gupta, R. U.S. Pat. Appl. Publ. US 2002 110,503 (Cl. 422-190; BOlD53/62), 15 Aug 2002, Appl. 780,079, 9 Feb 2001. 14. An apparatus removes CO from a hydrogen-rich gas stream in a hydrogen fuel cell system. CO fouls costly catalytic particles in the membrane electrode assemblies. Both a catalyst adapted to perform a water gas shift reaction, and a carbon dioxide adsorbent are disposed in a rotating pressure swing adsorber housing. The adsorption of carbon dioxide shifts equillibrium toward carbon monoxide consumption. A second adsorbent may be disposed in the housing for adsorbing carbon monoxide at low temperatures, and is adapted to desorb carbon monoxide at high temperatures. The present invention advantageously eliminates a unit operation from a space-constrained fuel cell vehicle by combining the WGS catalyst and a CO? adsorbent in a single reactor/housing. The apparatus further eliminates the: use of a PROX reactor, by providing an apparatus which incorporate*, CO?_ adsorption and consequent carbon monoxide consumption in the place of the PROX reactor.
03/00647 ANN for transmission system static security assessment Chauhan, S. and Dave, M. P. Irrtrtxntional Journal of Electricul Po\l’rr & Erzerg~~Sy.\terns, 2002, 24. (II)). 8677873. This paper presents computationally efficient artificial neural network technique for assessing the security of the power system against line outages. Performance index (PI), which accounts for various line limit violations per contingency, is defined. The basic purpose of artificial neural networks (ANN) is to assess the severity of line outages in terms of PI, based on training examples from off-line analysis. The selection of input signals for ANN is influenced by the operating state of the cystem and the contingency in question that determines the extent of line power limit violations. In an attempt to attain perfection in PI prediction, suitable architecture and topology for the network is investigated. To expedite learning process, saturating linear coupled neuron model (sl-CONE) i< also tried out. The effectiveness of
Fuel and Energy Abstracts
May 2003
153