Power cable line with current detector using giant magnetostrictive alloy and giant magnetostrictive alloy sensor

摘要

PROBLEM TO BE SOLVED: To make it possible to detect a current with high sensitivity by generating a large strain in a supermagnetostrictive alloy sensor and accurately sense a fault point using the sensor. SOLUTION: When a current flows to a power equipment or power cable, a uniform magnetic field is generated in the bent surface axial direction of a supermagnetostrictive alloy plate 3, and a magnetic strain is generated in the plate 3. Since both the ends of the plate 3 are restricted in the movement by the protrusion of a supermagnetostrictive alloy plate fixing adapter 2, the plate 3 is expanded in a circumferential direction and deformed. The deformation of the plate 3 is detected by a strain gage 5, sent to a strain measuring instrument 7 via a lead 6, and a strain amount is measured. A supermagnetostrictive alloy sensor is mounted at an ultrahigh voltage power cable, the strain of supermagnetostrictive alloy is detected by a strain sensor to make it possible to discriminate the ground-fault accident occurring section.