Matches in SemOpenAlex for { <https://semopenalex.org/work/W1551353585> ?p ?o ?g. }
Showing items 1 to 78 of
78
with 100 items per page.
- W1551353585 abstract "One of the major instabilities under study in the 0111-0 tokamak is the resistive wall mode (RWM), a form of plasma instability whose growth rate is moderated by the influence ofa resistive wall.l.2 The Far-Tech Olll-O/RWM model represents the perturbed magnetic fluctuations on the plasma surface as a toroidal current sheet and represents the resistive wall using an eigenmode approach. Although the plasma surface deformation cannot be directly measured in real time, the amplitude and phase of the RWM instability can be deduced from measurements by a set of 22 magnetic field sensors. An array of 6 internal control coil pairs can then be used to return the plasma to its original shape. Using a matched filter for the two orthogonal components (related by quadrature in toroidal angle) of a modeled toroidal mode, the resultant plant is reduced from a 22 by 6 system to a simple 2 by 2 system. Several control techniques are considered to stabilize this system. The control systems are created at a nominal growth rate and then implemented on plants of varying growth rates. The task is to find the upper and lower growth rate limits of the plant that can still be stabilized by the nominal controller. Two ranges of growth rates are found: one simply for stabilization, and another that satisfies a set of performance constraints required for quality design control. Based on these growth rate span results, the various approaches are compared for their individual advantages and disadvantages. This entire process is then applied to two 6 by 6 open-loop systems. Finally, the results of the two 6 by 6 systems are evaluated in comparison with the 2 by 2 system's results. Implications for experimental implementation and use are discussed. 1 Background The RWM is a type of plasma instability under the influence of the resistive wal1. The kink description is used to illustrate the plasma behavior because it acts much like a garden hose that kinks when abruptly pressurized. The toroidally shaped plasma deforms in a helically symmetric way and the toroidal mode number is used to characterize this deformed instability shapc. Thc most malignant toroidal modc is thc n= I mode, which occurs first with rising plasma pressure. The perturbed magnctic fluctuations on thc plasma surface associated with thc instability create cddy currcnts in thc surrounding conductive structurc, that is, thc wall. Thc prcscnce ofthc conducting wall convcrts thc plasma's cxtrcmcly rapid growth timc of a fcw microscconds into a combincd plasma/wall systcm with an instability having a slow growth timc on thc order ofthc rcsistive decay timc of eddy currents in the surrounding materials, which is a few milliscconds. The slowcr growth cnablcs the use of feedback to control the RWM instability. Thc parametcr p is dcfined as thc ratio of plasma kinetic pressure to magnetic prcssure that confines thc plasma. A primary dcfinition is where Pk equals the plasma kinetic pressure averaged over the plasma volume, BI is the vacuum toroidal magnetic field strength, and 1'0 is the magnetic permeability of the vacuum. In short, p is a mcasure of how effective the magnetic system is at containing the plasma. According to magnetohydrodynamic theory. a certain high plasma pressure makes the RWM unstable when the surrounding wall structure is far from the plasma surface. The critical plasma pressure threshold for this instability is expressed in terms of the n0n11alized beta. p~." @default.
- W1551353585 created "2016-06-24" @default.
- W1551353585 creator A5050300549 @default.
- W1551353585 date "2006-01-01" @default.
- W1551353585 modified "2023-09-26" @default.
- W1551353585 title "Comparison of potential approaches for resistive wall mode stabilization based on plasma eigenmode model" @default.
- W1551353585 cites W2131588967 @default.
- W1551353585 hasPublicationYear "2006" @default.
- W1551353585 type Work @default.
- W1551353585 sameAs 1551353585 @default.
- W1551353585 citedByCount "0" @default.
- W1551353585 crossrefType "journal-article" @default.
- W1551353585 hasAuthorship W1551353585A5050300549 @default.
- W1551353585 hasConcept C116515362 @default.
- W1551353585 hasConcept C119599485 @default.
- W1551353585 hasConcept C121332964 @default.
- W1551353585 hasConcept C127413603 @default.
- W1551353585 hasConcept C15001198 @default.
- W1551353585 hasConcept C154945302 @default.
- W1551353585 hasConcept C198394728 @default.
- W1551353585 hasConcept C207821765 @default.
- W1551353585 hasConcept C24890656 @default.
- W1551353585 hasConcept C2775924081 @default.
- W1551353585 hasConcept C30403606 @default.
- W1551353585 hasConcept C32758168 @default.
- W1551353585 hasConcept C33923547 @default.
- W1551353585 hasConcept C41008148 @default.
- W1551353585 hasConcept C47446073 @default.
- W1551353585 hasConcept C57879066 @default.
- W1551353585 hasConcept C62520636 @default.
- W1551353585 hasConcept C6899612 @default.
- W1551353585 hasConcept C82706917 @default.
- W1551353585 hasConceptScore W1551353585C116515362 @default.
- W1551353585 hasConceptScore W1551353585C119599485 @default.
- W1551353585 hasConceptScore W1551353585C121332964 @default.
- W1551353585 hasConceptScore W1551353585C127413603 @default.
- W1551353585 hasConceptScore W1551353585C15001198 @default.
- W1551353585 hasConceptScore W1551353585C154945302 @default.
- W1551353585 hasConceptScore W1551353585C198394728 @default.
- W1551353585 hasConceptScore W1551353585C207821765 @default.
- W1551353585 hasConceptScore W1551353585C24890656 @default.
- W1551353585 hasConceptScore W1551353585C2775924081 @default.
- W1551353585 hasConceptScore W1551353585C30403606 @default.
- W1551353585 hasConceptScore W1551353585C32758168 @default.
- W1551353585 hasConceptScore W1551353585C33923547 @default.
- W1551353585 hasConceptScore W1551353585C41008148 @default.
- W1551353585 hasConceptScore W1551353585C47446073 @default.
- W1551353585 hasConceptScore W1551353585C57879066 @default.
- W1551353585 hasConceptScore W1551353585C62520636 @default.
- W1551353585 hasConceptScore W1551353585C6899612 @default.
- W1551353585 hasConceptScore W1551353585C82706917 @default.
- W1551353585 hasLocation W15513535851 @default.
- W1551353585 hasOpenAccess W1551353585 @default.
- W1551353585 hasPrimaryLocation W15513535851 @default.
- W1551353585 hasRelatedWork W1976121268 @default.
- W1551353585 hasRelatedWork W1987095661 @default.
- W1551353585 hasRelatedWork W1994303501 @default.
- W1551353585 hasRelatedWork W1998958971 @default.
- W1551353585 hasRelatedWork W2016803442 @default.
- W1551353585 hasRelatedWork W2016828692 @default.
- W1551353585 hasRelatedWork W2019970874 @default.
- W1551353585 hasRelatedWork W2036239966 @default.
- W1551353585 hasRelatedWork W2048139839 @default.
- W1551353585 hasRelatedWork W2051042846 @default.
- W1551353585 hasRelatedWork W2051174774 @default.
- W1551353585 hasRelatedWork W2063969362 @default.
- W1551353585 hasRelatedWork W2066930425 @default.
- W1551353585 hasRelatedWork W2071021566 @default.
- W1551353585 hasRelatedWork W2139883813 @default.
- W1551353585 hasRelatedWork W2334135042 @default.
- W1551353585 hasRelatedWork W2791080676 @default.
- W1551353585 hasRelatedWork W2800400521 @default.
- W1551353585 hasRelatedWork W2891593111 @default.
- W1551353585 hasRelatedWork W3137060321 @default.
- W1551353585 isParatext "false" @default.
- W1551353585 isRetracted "false" @default.
- W1551353585 magId "1551353585" @default.
- W1551353585 workType "article" @default.