电缆分布电容对出口继电器动作的影响分析及应对措施

发布时间：2018-01-24 15:37

本文关键词： 分布电容直流接地动作功率动作电压母线电压　出处：《电力系统自动化》2017年15期 　论文类型：期刊论文

【摘要】：《国家电网公司十八项电网重大反事故措施》从设计角度对继电器动作功率和动作电压提出了要求,但在发生直流接地或交流窜入时,若控制电缆的分布电容超过临界值,出口继电器仍旧会误动作。从设备运维检修的角度,设计了一种电缆分布电容的在线监测系统,实现对该类风险的预警,并给出了相应的控制措施。该监控系统通过向直流系统注入低频交流信号,以交流电流为量测量,计算其分布电容并与临界值比较。为实现分布电容的平稳准确测量,基于磁饱和原理和磁通感应原理,设计了一种测量微小交直流信号的电流互感器;采用直流电子负载中的恒阻模式,设计了一种电压均衡模块来平衡直流母线电压。
[Abstract]:"State Grid Company" 18 major anti-accident measures of power grid. From the design point of view, the requirements for relay operation power and operating voltage are put forward, but when DC grounding or AC entering occurs. If the distributed capacitance of the control cable exceeds the critical value, the outlet relay will still misoperate. From the point of view of the maintenance and repair of the equipment, an on-line monitoring system of the cable distributed capacitance is designed to realize the warning of this kind of risk. The low frequency AC signal is injected into the DC system and the AC current is measured. The distributed capacitance is calculated and compared with the critical value. Based on the principle of magnetic saturation and flux induction, a kind of current transformer is designed to measure the small AC / DC signal based on the principle of magnetic saturation and magnetic flux induction. A voltage balancing module is designed to balance DC bus voltage using constant resistance mode in DC electronic load.
【作者单位】：国网上海市电力公司检修公司;河海大学能源与电气学院;国网技术学院;深圳奥特迅电力设备股份有限公司;
【基金】：国网上海市电力公司科技项目(SGSHJX00ZSJS1401134)资助
【分类号】：TM58
【正文快照】： 0引言当直流系统接地或交流窜入直流时,会通过电缆的分布电容构成回路,产生电容电流,导致一些动作值低、灵敏度高的继电器误动[1]。误动的主要因素为继电器的动作值(电压和功率)[2]、电缆对地的分布电容值[3]。《国家电网公司十八项电网重大反事故措施》6.7节中提出:所有涉及

【参考文献】