Residual life assessment of 110Â kV XLPE cable

In electric power transmission, 110 kV XLPE cables have been given a wide usage recently. Specific samples are selected as specimens of accelerated thermal aging tests and are tested at different temperatures. Once the value of the specimen elongation at break decreases to 50% of the initial value, the cable at this condition is no longer suitable to be tested. The data obtained in this condition are the standard of judgment as a test failure and are used for calculation of the residual life. The Arrhenius equation is used to calculate the residual life of the tested 110 kV XLPE cables based on the data obtained from the experiments. The calculation shows that the whole service life of a cable at different periods is consistent. Furthermore, the calculations prove that the method used to assess the cables' residual life is robust and reliable. The result of the experiment provide both theoretical and practical basis to replace 110 kV XLPE cables preventively.