Separable online electromagnetic non-destructive detection device for high-voltage transmission line

Abstract

The invention discloses a separable online electromagnetic non-destructive detection device for a high-voltage transmission line. The separable online electromagnetic non-destructive detection device comprises excitation direct-current electromagnets, a Hall sensor array and two half eddy current coil arrays, wherein the excitation direct-current electromagnets are arranged along the radial direction of the transmission line and are used for detecting a defect on a steel core of the transmission line; the Hall sensor array is used for detecting a butting position of the steel core at a joint of the transmission line; the two half eddy current coil arrays are used for detecting broken strand of a stranded aluminum line on the outer layer of the transmission line; the separable online electromagnetic non-destructive detection device can be conveniently mounted on the transmission line and can surmount obstacles. The excitation direct-current electromagnets and the Hall sensor array can be completely separated from the transmission line; the magnetic cores of the magnets are placed along the radial direction of the transmission line, so that the distance between two poles is greatly shortened, and the loss of magnetic flux is reduced. A direct-current electromagnetic field is generated by energizing two coils, the saturation magnetization of the transmission line is facilitated, and the sensitivity of the detection is improved. Each group of coils in the two half eddy current coil arrays adopts a dual-excitation mode, so that the penetration depth of the eddy in the transmission line is increased, and the detection of deep cracks and damages is facilitated.

Description

technical field [0001] The invention relates to a non-destructive testing technology, in particular to a detachable on-line electromagnetic non-destructive testing device for a high-voltage transmission line. Background technique [0002] At present, the integrity of the high-voltage transmission line structure is very important for the safe operation of the transmission system. Since the transmission line works outdoors, it has been subjected to huge alternating tension and bending stress caused by vibration for a long time, which will inevitably cause cracks and broken strands in the conductors and ground wires of the transmission line. In addition, the surface of the transmission line will be damaged due to rapid changes in temperature and lightning strikes. If it is laid on the seashore or in an industrial area, it is easy to cause corrosion damage due to salt spray and acid rain. In addition, it is more likely to cause danger at the joint of the transmission line, beca...

AI Technical Summary

Problems solved by technology

In this patent application, the Hall sensor unit is arranged in the gap between the electromagnet core and the transmission line. Due to the limitation of the maximum detection range of the Hall sensor (usually 0.06 ~ 0.07T), the electromagnetic field in the magnetic circuit cannot be increased to The magnetic field strength of saturation magnetization, otherwise it will exceed the maximum detection range of the sensor and cause no change in the magnetic field strength to be detected

[0006] In this patent CN103645243A, the copper wires of the two separable eddy current coils are directly wound on the two halves of the plastic coil frame, so that there are only two independent coils in the circumferential direction of the transmission line, which cannot damage the aluminum stranded wire. Circumferential position for accurate judgment

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