Defect Diagnosis Method of Cable Shielding Layer Based on Frequency Domain Reflection Coefficient Spectrum

In this article, the genetic algorithm-variational mode decomposition-reflection coefficient spectrum (RCS) method is proposed based on frequency domain RCS to detect and locate the weak defects of the cable shielding layer more precisely. In this method, variational mode decomposition (VMD) algorithm is applied on the RCS to extract defect information, and genetic algorithm based on envelope entropy and kurtosis is adopted to optimize the number of decomposed intrinsic mode functions and penalty factor of the VMD. In addition, with 40 groups of data, support vector machine algorithm is engaged to identify the types of different shielding layer defects. The experimental results show that the proposed method can detect and locate weak defects, such as one-strand fractures and holes, and meanwhile identify the types of defects accurately.