Design of a Digital Signal Current Detector
The single-phase earthed protection based on the S’ signal injection method has been successfully applied for more than ten years in non-effective earthed power system in China. Detecting and processing the injected weaker diagnostic current has always been implemented by analog integrated circuits. But its measuring accuracy and interference rejection are limited. So, a digital signal current detector (DSCD) is designed in this paper. According to characteristics of the injected diagnostic current and requirements for detecting it, the design solution for the DSCD is proposed. High performance digital filters are designed. And the amplitude of the injected current is calculated by Fourier algorithm. The DSCD samples the injected diagnostic current by the high-accuracy Analog-to-Digital converter ADS8325 and processes it by the mixed signal microcontroller MSP430 family. Field applications verified the effectiveness of the project.
Non-effective earthed power system Single-phase earthed fault S’ signal injection method Signal Current Detector Digital Filter
Xiuxiang Zhu Huifen Zhang Ying Zhang
School of Control Science and Engineering, University of Jinan, Jinan, 250022
国际会议
The 22nd China Control and Decision Conference(2010年中国控制与决策会议)
徐州
英文
1713-1717
2010-05-26（万方平台首次上网日期，不代表论文的发表时间）