Correlation Analysis of Aging Indicators for Distribution Network XLPE Cables

In order to improve the practice in the diagnosis of distribution network XLPE cables, accelerated thermal aging tests have been carried out for a 10 kV XLPE (cross-linked polyethylene) cable to obtain the aging samples. Then, the Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), differential scanning calorimetry(DSC), hermogravimetry (TG) and derivative thermogravimetric (DTG) tests have been carried out to characterize the aging state of the XLPE samples. Further, canonical correlation analysis (CCA) and PCCA (probabilistic CCA) have been used for the correlation analysis of all the test results. The correlation analysis indicates the similar trends: as the aging time increases, the correlation degree of the characterization curves decreases. All the FTIR, XRD, DSC, TG and DTG results can characterize the aging state in different degrees. Among them, the TG test cannot fully distinguish the aging state of the XLPE samples, and the DSC test has a relatively better linear distinction for the aging state of the XLPE samples.