Cables XLPE-insulation Residual Life Monitoring

Abstract

Cable insulation is the most destructible element of the cable system. Therefore, insulation materials aging research continues to be one of the topical problems. However, it is possible not only to calculate the insulation life but also to monitor its residual life. The paper describes a technique of the cable XLPE-insulation residual life monitoring. It is based on the Kuchinsky insulation aging mathematical model, which has been improved and transformed to calculate the insulation residual life. Besides, this mathematical model was not considered enough in the known literature. The basic data for the calculation of the XLPE-insulation residual life are a cable insulation electric field and temperature. They are non-uniform so their distribution is accounted in the residual life computing algorithm. Therefore, the insulation wear is also non-uniform and more significant in the field of the cable core. The simulation of the residual insulation life monitoring is done using the data of the cable insulation voltage and temperature. The temperature distribution is calculated using the data about the cable core and screen currents. The result of the simulation shows the ability of the technique to monitor the insulation residual life. Besides, the technique might be implemented in the digital substation systems, intellectual power grids and other technologies using current and voltage monitoring.