Download or read book Electron Cyclotron Emission Imaging System for HL-2A Tokamak written by Shao Che and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Magnetic confinement thermonuclear fusion energy has long been considered a potential substitute for fossil fuels as the major long term energy source of global development. With its effective magnetic field configuration, tokamak devices have received extensive investigations with advancement in plasma diagnostic tools [1]. A comprehensive millimeter wave passive imaging diagnostic system for measurement of electron temperature fluctuations in tokamaks has been conceived and developed at the University of California at Davis utilizing the Electron Cyclotron Emission from the plasma [2,3]. HL-2A is a diverted tokamak developed and constructed by the Southwestern Institute of Physics (SWIP) in Chengdu, China based on the vacuum vessel and magnetic coil system of the former German ASDEX device. Previous millimeter wave diagnostics including reflectometry and ECE radiometry have been installed on the tokamak for electron density and temperature profile measurements [4,5]. However, there is increasing need for fluctuation measurements over the plasma volume for research into plasma confinement and instabilities. Through a collaborative effort between the Davis Millimeter Wave Research Center (DMRC) of the University of California at Davis and SWIP, a new 192 channel (24 vertical by 8 radial) Electron Cyclotron Emission Imaging system has been designed and constructed at UC Davis for a 2 dimensional coverage of the plasma temperature with high spatial resolution. A new imaging optical system with zooming capability is optimized for the available port window on HL-2A with a versatile coverage of the plasma volume ranging from a magnification ratio of 1 to 1.8. A novel local oscillator (LO) optical system is designed to maintain the optimum illumination onto the antenna array under different operating frequencies of the Backward Wave Oscillator. The RF electronics for double down-conversion heterodyne frequency mixing and signal detection is developed from the DIIID ECEI system with improved sensitivity and reduced noise. Other millimeter wave components such as the dual-dipole antenna array and dichroic plate high-pass filters are fabricated and characterized. The complete system is assembled and calibrated in the laboratory at UC Davis with extensive testing and characterization of the functionality of each subsystem.