The lead sealing process

one of key production processes of high-voltage cable accessories

can easily lead to unreliable electrical connection or water ingress and then cause high-voltage cable line fault after cracks in response to poor installation quality or pulling force and vibration occur in the operation. Consequently

we proposed an eddy current test for solving the problem of lacking technological means in evaluating lead sealing quality and detecting operation state. The analysis reveals that the loop resistance detection and X-rays detection can not be applicable to lead sealing field detection

thus the research is carried out on eddy current detection technology. Firstly

we compared the differences of eddy current detection results in an uncracked state and cracked states to different extent by using lead sealing artificial defect simulations of 110 kV high-voltage cable. Then

we adopted a high-voltage cable typical defects simulation platform to simulate the actual operation conditions of the cable

and analyzed the electromagnetic interference influenced on eddy current detection results. Finally

we applied the eddy current detection to field tests of 220 kV high-voltage cable. The results show that the eddy current detection can effectively detect the defects of the high-voltage cable lead sealing such as voids and cracks. There is a significant difference in the amplitude

phase and figure-8 curve of the spectrum under the conditions of lead sealing defect and under zero-defect. The more serious the lead sealing crack is

the greater the signal strength will be. The electromagnetic interference does not affect the results of the eddy current detection of the lead sealing during high-voltage cable operation. The research results can provide an important reference for installation quality evaluation and running state detection of high-voltage cable lead sealing.