光电磁同步融合的弧光检测与保护

Arc Detection and Protection Based on the Synchronous Fusion of Light,Electricity and Magnetism

中压配电网开关柜所处的内外部工作环境复杂,易发生接地故障,产生的故障电弧严重危及人身安全与设备安全,现有弧光保护技术与装置的可靠性不高、灵敏性不足。发明了一种故障电弧的光、电、磁同步融合检测方法:利用电弧起弧阶段产生的特定波段的紫外光强增量与电压梯度构成或逻辑作为启动判据;利用电弧燃弧阶段可见光强增量和零序暂态电流变化趋势增量的正相关相似度作为出口;实现了开关柜内接地故障电弧光电磁同步检测,突破了接地弱电流故障分量检测的瓶颈。弧光保护出口时间不大于5 ms,包括断路器动作时间,整个保护时长小于35 ms,远小于电缆起燃的时间,避免了开关柜接地电弧发展成稳定电弧,避免永久故障的形成,提高了开关柜运行安全性与可靠性。

The internal and external working environment of the switchgear of the medium voltage distribution network is complex,and ground faults are prone to occur.The resulting arc fault seriously endangers personal safety and equipment safety.The existing arc protection technology and devices are not highly reliable and sensitive.Invented a synchronous fusion detection method of optical,electrical,and magnetic for arc faults:using the specific waveband ultraviolet light intensity increment and voltage gradient composition or logic generated during the arc starting stage as the starting criterion;Use the positive correlation similarity between the increase in visible light intensity and the trend increase in zero-sequence transient current during the arc ignition phase as an export;It realizes the electromagnetic synchronous detection of the ground fault arc in the switchgear,and breaks the bottleneck of the detection of the weak ground current fault component.The arc protection exit time is no more than 5ms,including the circuit breaker action time.The entire protection time is less than 35ms,which is much less than the cable ignition time,which prevents the switch cabinet grounding arc from developing into a stable arc,avoids the formation of permanent faults,and improves the switch Safety and reliability of cabinet operation.