Signal processing for all fiber optical current transducer
来源期刊:中南大学学报(英文版)2008年第z2期
论文作者:裴焕斗 祖静 陈鸿
文章页码:404 - 408
Key words:fiber optical current transducer; demodulation; signal processing; ratio error
Abstract: The work principle of all fiber optical current transducer (AFOCT) was introduced. By analyzing the characteristic of photo-detector’s output, a measurement and signal processing scheme based on sine wave modulation and demodulation was put forward for eliminating the influence of light intensity change and modulation degree change. A digital signal processing system and a calibration scheme were also advanced. The experimental data show that the mean ratio error is 0.016 74% for direct current and 0.035% for alternating current, and the correlation coefficient of linearity is up to 0.999 982 4, meeting the precision requirement of 0.2 grade. Stability experiments and temperature drift experiments show the AFOCT has a better stable capability.