Research on the Detection of the Broken Wire Damage of a Cable in the Circumferential Directions Based on Self-magnetic Flux Leakage

For large section members such as cables, there are insufficient methods for circumferential scanning along the cable sections for the detection of corroded broken wires. In this study, a detection method for broken wire damage (BWD) along the circumferential direction of cable based on the principle of self-magnetic flux leakage (SMFL) was proposed. First, the theoretical calculation model and the finite element model of the circumferential magnetic field in the polar coordinate system were established. The analysis results showed that the position of the BWD on the section of cable could be effectively judged by the concave position of the curves of the SMFL in the polar coordinate system. Through the circumferential scanning at different positions, the length of the BWD could be judged by the coordinates of x when the value of index “C” (similarity to circle) approached 1 for the first time in the x − C curves. Finally, the detection experiment for the BWD of a parallel wire bundle was carried out. The experimental results were consistent with the analysis results for the theoretical model and the finite element, and the experimental results verified the correctness of the detection method.