Diagnosis of XLPE Cable Insulation Using Velocity of Electromagnetic Wave

The research on diagnosis of XLPE power cable insulation is of a great importance for realizing the cable insulation aging status and ensuring the power transmission system in safe and reliable operation.Therefore,we put forward a new method,using electromagnetic wave propagation velocity in an XLPE cable as the criterion of whether the aging happens in the cable,set out the principles of the method and theoretical basis,and built a test platform.In accordance with the method proposed,we measured two different levels of water tree aged XLPE cables.During the measurement data processing,we also researched how to get the round-trip time effectively.The result indicates that using electromagnetic wave speed for diagnosis of XLPE cable insulation can reflect the insulation status of the two XLPE cables primly.Comparison of the different results suggests that this method is accurate and reliable,so as to provide new ideas for diagnosis of XLPE cable insulation.