Dielectric breakdown statics of withdrawed XLPE cables and running cables in 22 kV class

摘要

The failure rate of the 22 kV class XLPE cable in service was calculated by using the data of service year — breakdown characteristics of the withdrawed cables. The calculated result considerably coincide the actual failure rate when the breakdown strength Is assumed to be 12.7 kV (the working stress), suggesting that the withdrawed cables are more deteriorated than the running cables. In order to assume the failure rate of the running cable more exactly, it is required to keep the data such as the electrical stress distribution, the length and the replacement records of the running cables.