Comparative tests of impulse strength of PE and XLPE insulation

摘要

The ever increasing utilisation of medium and high voltage cable lines stimulates the activity of the cable manufacturing industry in the area of research aimed at finding design solutions guaranteeing even higher reliability of those lines.This objective is met through the use of better materials, improved manufacturing technology and the creation of an optimal scope of final cable qualify test. In order to decrease losses in insulation the construction changes incables are designed to introduce insulation materials boasting a decreased dielectric losses coefficient. For this reason FE and XLPE insulation is used in numerous applications, with users taking advantage of its good operatingparameters and environmental protection. Insulation of constant voltage appliances is highly polarised and is also subjected to overvoltage. This can adversely affect the reliability of the line. That is why the present comparativetests of the influence of time and polarisation tension upon FE and XLPE impulse strength have been conducted.