单相供用电系统故障漏电电流特征及保护方法  

Fault leakage current characteristics and protection methods of single-phase power supply and consumption system

作　　者：李奎[1] 王超然 王尧[1] 武一[1] LI Kui;WANG Chaoran;WANG Yao;WU Yi(Key Laboratory of Electromagnetic Field and Electrical Apparatus Reliability of Hebei Province,Hebei University of Technology,Tianjin 300401,China)

机构地区：[1]河北工业大学河北省电磁场与电器可靠性重点实验室,天津300401

出　　处：《天津工业大学学报》2023年第4期63-70,共8页Journal of Tiangong University

基　　金：国家自然科学基金资助项目(51977059);河北省自然科学基金资助项目(E2020202042)。

摘　　要：为解决供用电系统和用电设备的正常漏电电流与故障漏电电流的保护和识别问题,首先针对供用电系统和用电设备的漏电特征进行分析,明确正常漏电与故障漏电的识别特征;其次分析高频电力电子设备的漏电电流特征,提出基于高频电流负反馈的磁调制漏电电流量测方法,实现故障漏电的准确检测与保护;最后提出基于漏电电流阻容特征的单相供用电系统的漏电保护策略,分别设置故障漏电动作阈值和正常漏电动作阈值,在保障供用电系统和用电设备正常运行的前提下实现故障漏电的准确保护。结果表明:正常漏电与故障漏电电流阻容特征不同;基于高频电流负反馈的磁调制漏电电流量测方法可以有效降低正常高频容性漏电电流的影响;基于漏电电流的阻容特征的漏电保护策略,可提高漏电保护的有效性和可靠性。In order to solve the protection and identification of normal leakage current and fault leakage current of power supply and consumption system and electrical equipment,firstly,the leakage characteristics of power supply and consumption system and electrical equipment are analyzed.Identify the identification characteristics of normal leakage and fault leakage;secondly,the leakage current characteristics of high-frequency power electronic equipment are analyzed.A magnetic modulation leakage current measurement method based on high frequency current negative feedback is proposed to realize the accurate detection and protection of fault leakage;finally,the leakage protection strategy of single-phase power supply and consumption system based on the characteristics of leakage current resistance and capacitance is proposed.Set the fault leakage action threshold and normal leakage action threshold respectively,on the premise of ensuring the normal operation of power supply and consumption system and electrical equipment,the accurate protection of fault leakage is realized.The results show that the characteristics of normal leakage current and fault leakage current are different;the magnetic modulation leakage current measurement method based on the negative feed-back of high-frequency current can effectively reduce the influence of normal high-frequency capacitive leakage current;the leakage protection strategy based on the resistance capacitance characteristics of leakage current can improve the effectiveness and reliability of leakage protection.

关 键 词：分布式阻抗 阻性漏电 容性漏电 电流测量 故障漏电保护 

分 类 号：TM930.1[电气工程—电力电子与电力传动]