Study of Fluxgate Current Detecting Method for AC-DC Earth Leakage Current Based on apFFT
Wang Yao1, 3, Li Kui1, Ren Bofei1, Zou Xu1, Ge Leijiao2, Ye Haiwu3
1. Province-Ministry Joint Key Laboratory of Electromagnetic Field and Electrical Apparatus Reliability Hebei University of Technology Tianjin 300130 China; 2. Tianjin University Tianjin 300072 China; 3. People ELE. Appliance Group China Wenzhou 325604 China
Abstract：The earth leakage current of power electronic equipment is a complicated signal when an earth fault occurs. The conventional current detecting methods based on electro-magnetic induction, hall-effect or fluxgate with double cores fail to meet the demand for such complicated signals. This paper proposes a fluxgate current detecting method for AC-DC earth leakage current based on apFFT. A voltage-based fluxgate current sensor with single core is used to detect AC-DC earth leakage current, so that the structure of the current sensor can be simplified. Meanwhile, apFFT is used to process the signals to simplify the structure of the demodulation circuit. Test results show that spectrum leakage is suppressed effectively due to apFFT and good detecting accuracy is obtained.
王尧, 李奎, 任伯飞, 邹旭, 葛磊蛟, 叶海武. 基于全相位傅里叶变换的磁调制交直流漏电电流检测方法[J]. 电工技术学报, 2015, 30(18): 254-260.
Wang Yao, Li Kui, Ren Bofei, Zou Xu, Ge Leijiao, Ye Haiwu. Study of Fluxgate Current Detecting Method for AC-DC Earth Leakage Current Based on apFFT. Transactions of China Electrotechnical Society, 2015, 30(18): 254-260.
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2015, Vol. 30 
