The invention discloses a high-
voltage cable sheath
circulating current monitoring device based on a Faraday
magneto-optical effect, which comprises a
light source excited to emit light, one end of a coupler is connected with the
light source and one end of a first photoelectric
detector, and the other end of the coupler is connected with one end of a
polarizer; one end of the
beam splitter is connected with the other end of the
polarizer and one end of the second photoelectric
detector, and the other end of the
beam splitter is connected with one end of the
polarization beam splitter, and the other end of the
polarization beam splitter is connected with one end of the polarization
light switch. The other end of the polarized
light switch is respectively connected with the A-phase operation current sensing unit, the B-phase operation current sensing unit, the C-phase operation current sensing unit and the Ln joint sheath
ring current sensing unit; and the acquisition
control circuit is respectively connected with the
light source, the other end of the first photoelectric
detector, the other end of the second photoelectric detector and the polarized
light switch. According to the invention, one monitoring device is used for simultaneously monitoring the sheath circulation signals of a plurality of measuring points and the operating currents of A, B and C phases, and the cost is greatly reduced.