摘要
根据专用仪器对五个变电站在线运行直流绝缘监测仪现场校验结果进行分析,发现被校验的直流绝缘监测仪存在两极接地不能正确告警和选线。当存在对地电容时会误选线、漏选线以及电压波动大等问题。探讨了直流系统两极接地以及检测接地支路切换过程中产生的电压波动而导致保护误动的安全隐患,提出了采用专用设备对直流绝缘监测仪进行现场定期校验,及时发现和消除所存在的安全隐患,确保直流系统安全稳定运行。
The paper analyzes the field calibration results on the DC insulation monitor operated online in five substations with special instruments , finds that when two poles earth occur, correct alarm and line selection are not completed by the DC insulation monitor. Error and missing line selection as well as oversize voltage fluctuation appear when ground capacitance takes place. Also the paper discusses the security risk of the relay acting incorrectly that caused by the voltage fluctuating created in the process of two poles ground and detecting the grounding branch switching. Finally, the paper proposes using a special apparatus to calibrate the DC insulation monitor apparatus to find out and avoid the security risk, thus to ensure the safe and stable operation of DC system.
出处
《电力系统保护与控制》
EI
CSCD
北大核心
2010年第19期226-228,231,共4页
Power System Protection and Control
关键词
绝缘监测仪
两极接地
误选线
漏选线
电压波动
现场校验
DC insulation monitor
two poles ground
falsely select the line
miss selecting the line
voltage fluctuation
field calibration
