Cart (Loading....) | Create Account
Close category search window
 

Real-Time Tomography System at ISTTOK

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

6 Author(s)
Carvalho, P. ; Fus ao Nucl.-Lab. Associado, Inst. Super. Tecnico, Lisbon, Portugal ; Duarte, P. ; Pereira, T. ; Coelho, R.
more authors

A real-time plasma position control system is mandatory to achieve long duration (up to 250 ms), Alternating Current (AC) discharges on the ISTTOK tokamak. Such a system has been used for some time supported only on magnetic field diagnostic data. However, this system is clearly challenged when the plasma current is low, rendering it inoperative during the plasma current reversal. A tomography diagnostic with 3 pinhole cameras and 8 silicon photodiode channels per camera was installed and customized to supply alternative plasma position to be used for plasma position control. As no filtering is applied most of the radiation detected is in the visible/near-UV range. The data acquisition and control system is based on a 2MSPS, 32 channel acquisition ATCA module and the data processing is performed on a GPU that is connected to another ATCA module via the PCI-Express port for fast data access. Control commands are relayed to the plasma positioning PF power supplies via optical serial ports. In this work, an overview of some of the tomographic reconstruction algorithms most commonly used for tokamak plasmas is done and an assessment is made on the best candidate for the proposed real-time implementation. The tomography acquisition and plasma control systems operating at ISTTOK are also described. This system aims at achieving the following goals: (i) execute a tomographic reconstruction; (ii) determine the average emissivity position from it; (iii) calculate the shift from the axis and (iv) supply the vertical field power supply with the desired current value, all in less than 100 μs. The horizontal magnetic field power supply unit, essential for vertical plasma positioning, is foreseen to be integrated in the system and will have no impact in the processing time.

Published in:

Nuclear Science, IEEE Transactions on  (Volume:58 ,  Issue: 4 )

Date of Publication:

Aug. 2011

Need Help?


IEEE Advancing Technology for Humanity About IEEE Xplore | Contact | Help | Terms of Use | Nondiscrimination Policy | Site Map | Privacy & Opting Out of Cookies

A not-for-profit organization, IEEE is the world's largest professional association for the advancement of technology.
© Copyright 2014 IEEE - All rights reserved. Use of this web site signifies your agreement to the terms and conditions.