The invention discloses an arc light online monitoring device for an
energy storage power distribution switch cabinet, and belongs to the technical field of arc fault monitoring. Comprising a monitoring unit and a collecting unit, a
quartz window short horn mouth captures 2pi spherical degree arc light at a time, and a closed
plastic optical fiber sends a pulse into an
integrating sphere within 50 microseconds; a
black body extinction cylinder-
narrow band filter-
integrating sphere multi-stage attenuation is carried out, strong light is weakened firstly, then an
ultraviolet characteristic spectrum is extracted, flash of a background lamp and a camera is completely eliminated, arc light position offset still keeps stable output, and high
signal-to-
noise ratio identification is realized; a real arc is judged according to the ratio of pure arc light to total light, and interference is avoided; after confirmation, a level in direct proportion to energy is output immediately, a background acts according to a three-level strategy of prompting,
tripping and quick breaking, no optical cable is exposed in the whole process, the whole process is not influenced by dust condensate water, a
closed loop from arcing to protection decision is completed within 2 ms, and real-time, reliable and maintenance-free arc light online monitoring is provided for an
energy storage power distribution switch cabinet.