Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2009-2-4
pubmed:abstractText
Electron cyclotron heating (ECH) is widely used in magnetic fusion devices, and the polarization of the injected millimeter-wave beams plays a crucial role in the propagation and absorption of the beam energy by the plasma. This polarization can be adjusted by grating mirror polarizers placed in the transmission lines which carry the microwaves from the power source to the plasma. In long-pulse devices such as the Large Helical Device (LHD) and ITER, it is desirable to track changes in the plasma and adjust the polarization of the ECH in real time such as to keep the absorption as high as possible and avoid shine-through which may lead to overheating of vessel components. For this purpose a real-time feedback control scheme is envisioned in which a measure of the absorption efficiency can be used to adjust the orientation of the polarizing mirrors toward an optimum. Such a setup has been tested in a low-power test stand as preparation for future implementation in the LHD ECH system. It is shown that a simple search algorithm is efficient and can in principle be used to control either the absorption efficiency or the linear polarization angle.
pubmed:language
eng
pubmed:journal
pubmed:status
PubMed-not-MEDLINE
pubmed:month
Jan
pubmed:issn
1089-7623
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
80
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
013504
pubmed:year
2009
pubmed:articleTitle
Real-time feedback control of millimeter-wave polarization for LHD.
pubmed:affiliation
Centre de Recherches en Physique des Plasmas, Association EURATOM-Suisse, Ecole Polytechnique Federale de Lausanne, 1015 Lausanne, Switzerland. federico.felici@epfl.ch
pubmed:publicationType
Journal Article