18-10-2009, 04:00 PM
plz send me details on superconducting generators
18-10-2009, 04:00 PM
plz send me details on superconducting generators
20-10-2009, 03:19 PM
man please read https://seminarproject.net/Thread-Superc...-Generator i think it may suffient for knowing whats Superconducting Generator
23-02-2011, 11:57 PM
i need a pdf document,ppt and a report work on superconducting generators
18-04-2011, 11:06 PM
hi
you can refer this page to get the details on super-conducting-generators https://seminarproject.net/Thread-super-...generators
20-08-2012, 01:21 PM
Superconducting Generators
Hts generator.docx (Size: 1.2 MB / Downloads: 67) ABSTRACT The superconducting generator using super conductors in field winding is superior to conventional generator in terms of power system stability, generator efficiency, generator dimensions and weight. They have been expected as a key generator technology to realize large capacity more them 1GVA.. Recently for then advantages are pointed out compared to conventional generator like small internal impedance that is effective to make system voltages in deregulated power system. These technical merits have pushed the development of superconducting generator in Japan, US, Germany and other countries. This paper covers the structural details of rotor and stator, the working and the cooling system for super conducting field windings. Also the main features and research and development on super conducing generator are covered briefly. . Fundamental technology for higher density and larger capacity is now under research. It is expected that superconducting generators becomes superior to conventional generators from economical and performance point of view. Superconducting generators are useful for solving problems appeared in power system and they are expected to the major source of electrical power in the coming decades. T h e H i s t o r y o f Superconductors Superconductors, materials that have no resistance to the flow of electricity, are one of the last great frontiers of scientific discovery. Not only have the limits of superconductivity not yet been reached, but the theories that explain superconductor behavior seem to be constantly under review. In 1911 superconductivity was first observed in mercury by Dutch physicist Heike Kamerlingh Onnes of Leiden University (shown above). When he cooled it to the temperature of liquid helium, 4 degrees Kelvin (-452F, -269C), its resistance suddenly disappeared. The Kelvin scale represents an "absolute" scale of temperature. Thus, it was necessary for Onnes to come within 4 degrees of the coldest temperature that is theoretically attainable to witness the phenomenon of superconductivity. Later, in 1913, he won a Nobel Prize in physics for his research in this area. Superconductors And a Periodic Chart Comparison The Type 1 category of superconductors is mainly comprised of metals and metalloids that show some conductivity at room temperature. They require incredible cold to slow down molecular vibrations sufficiently to facilitate unimpeded electron flow in accordance with what is known as BCS theory. BCS theory suggests that electrons team up in "Cooper pairs" in order to help each other overcome molecular obstacles - much like race cars on a track drafting each other in order to go faster. Scientists call this process phonon-mediated coupling because of the sound packets generated by the flexing of the crystal lattice. Type 1 superconductors - characterized as the "soft" superconductors - were discovered first and require the coldest temperatures to become superconductive. They exhibit a very sharp transition to a superconducting state (see above graph) and "perfect" diamagnetism - the ability to repel a magnetic field completely. Below is a list of known Type 1 superconductors along with the critical transition temperature (known as Tc) below which each superconducts. The 3rd column gives the lattice structure of the solid that produced the noted Tc. Surprisingly, copper, silver and gold, three of the best metallic conductors, do not rank among the superconductive elements. Why is this ? High Temperature Superconductivity The History of Superconductivity Superconductivity was discovered in 1911 by the Dutch physicist, Heike Kammerlingh Onnes. Onnes dedicated his science career to the studies of the properties of materials at extremely cold temperatures. In order to study materials at these very low temperatures, major advances in refrigeration had to be made. The first advance was the invention of a vacuum insulated cryostat- a cryostat is essentially a large "thermos bottle" designed for low temperature research. A few years later on July 10, 1908, Onnes liquefied a few drops of helium by cooling it to 452 degrees below zero Fahrenheit (or 4 Kelvin’s or 4 K); this was the start of his explorations in the properties of materials at low temperatures previously unreachable. Liquid helium enabled him and future scientists to cool materials to temperatures within 4 Kelvin’s of Absolute Zero (0 Kelvin’s), the coldest temperature physically possible. Absolute Zero is the temperature at which the thermal energy of atoms becomes as small as possible. Later in 1911, Onnes began to study the electrical properties of metals at these newly accessible low temperatures. It was known that the resistance of metals dropped as the temperature was lowered, but, no one knew how much the resistance would drop as one approached Absolute Zero. Some scientists including William Kelvin, believed that the electrons would actually stop as temperature reached Absolute Zero causing the resistance to increase. Other scientists including Onnes, believed that the resistance would continue to decrease and disappear completely only at Absolute Zero. Still others felt that a plateau in resistance would be reached at some low temperature. High Temperature Superconducting Materials & Devices group In the High Temperature Superconducting Materials & Devices group, the development of (Bi,Pb)2Sr2Ca2Cu3O10+x [Bi-2223] bulk tube/rod and current leads and long length tapes for high current transport was taken up. A pair of bulk tube (L=430mm, OD=48mm, ID=46mm) joint current leads carrying transport critical current of 85% of that of the individual tube carrying >1KA at 77K in self field has been developed. Optimization of preparation parameters to improve the transport current through the joint is in progress. Multi-filamentary Bi-2223 tapes (> 35 m long) having 7, 13 and 21 filaments carrying Ic ~7-10A at 77K in self-field have been developed. To understand the nature of pairing and in search of effective pinning centers, CESR studies of Bi-2223 samples doped with Pr (0-0.1M%) prepared under optimized conditions have been carried out at RT and 77K. Presence and disappearance of CESR signal along with Platzmann- Wolf lines at RT and 77K respectively confirms further the role of enhanced exchange interaction in this HTS system. Temperature/angular variation studies of this series are in progress. XRD, SEM of these samples have also been carried out. AC susceptibility and RT measurements of these samples showed a slight decrease in Tc from 112K for pure and 110K for 0.10M% Pr doped sample (Fig. 4.10). Transport Jc of bar-shaped samples (L=35mm,W=12mm,t=2mm) is in the range of 103 to 102A at 77K in self field.
04-10-2012, 06:46 PM
Helow, I am looking for a model for the superconductying generator in the D-Q park 's refrence with the constant time and the sunchronous reactance
05-10-2012, 12:07 PM
to get information about the topic "superconducting generators" full report ppt and related topic refer the link bellow
https://seminarproject.net/Thread-super-...-generator https://seminarproject.net/Thread-super-...ator--6505 https://seminarproject.net/Thread-superc...#pid115931 https://seminarproject.net/Thread-downlo...-generator |
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