Attempt to Location and Diagnosis of Cross Interconnection Cable based on FDR

Frequency domain reflection method (FDR) and characteristic time domain recovery technique are one of the effective methods to locate and diagnose cable impedance discontinuities. However, the location and diagnosis mothed of impedance discontinuities of cross interconnected HV cables have not been studied. This paper tries to use FDR method and feature time domain recovery technology to locate and diagnose cross-connected box. Firstly, the principle of local defect location and feature time domain recovery based on FDR method are described. Secondly, the reflection coefficient model of the head of cross-connected cable is derived by reflection coefficient method, which shows the feasibility of FDR method. At last, the laboratory 35kV XLPE cross-connected cable with a length of 350m was tested. The measured results show that the method based on FDR can effectively locate the cross-connected box and calculate its characteristic reflection time domain waveform.