摘要
等离子体电子密度是托卡马克物理研究中一个重要的物理量,它是表征等离子体特性的一个重要参数。本文介绍J-TEXT托卡马克装置中HCN激光干涉仪测量等离子体电子密度的基本原理,并采用软件相位差法获得等离子体电子密度,详细叙述该软件算法流程。该算法采用傅里叶变换法获得HCN相位差值,用数字滤波器对信号进行去噪处理,该算法能够准确地去除零漂,有效的进行信号翻转处理,实现对等离子体电子密度的准确测量。该系统已在J-TEXT装置实验中成功应用,获得了高精度低噪音的等离子体电子密度值,为相关物理研究提供了重要的数据。
The plasma electron density is an important physical quantity in plasma physics research,which is one of the important parameters for characterization of plasma characteristics.This paper describes the basic principle of the HCN laser interferometer for the J-TEXT Tokamak to measure the plasma electron density and gives the way to calculate the electron density of HCN signal.Fast Fourier transform is used in signals’ phase comparison.It can remove the zero drift and deal with the signal turning effectively.The digital filter is used to eliminate the noise in signal,and the HCN signal which has the high precision and low noise is gotten.Using a better signal can more precisely reflect the spatial distribution of the plasma density.It’s confirmed that the phase technology of the Fourier transform is reliable and correct.It not only can reflect the electron density changes,but also improve the density curve to a certain extent.
出处
《电子测量与仪器学报》
CSCD
2012年第10期851-857,共7页
Journal of Electronic Measurement and Instrumentation
基金
中央高校基本科研业务费专项资金(编号:2011HGBZ1313)资助项目
国家自然科学基金(编号:11105028)资助项目
科技部ITER计划国内专项(编号:2010GB108004
2010GB107003)资助项目
