Abstract
Cable XLPE-insulation operation capability and reliability highly depends on its insulation condition. Statistical analysis showed that more than 70% of cable technological disturbances are insulation breakdowns, caused by insulation aging or poor quality of cable jointing. This paper is devoted to the cable XLPE-insulation aging under the influence of electro-thermal stress. The goal of the research is to develop the technique of cable insulation residual life calculation. Theoretical and experimental research was carried out for this goal. During theoretical research Kuchinsky insulation aging model was considered and statistical research of cable insulation breakdown was performed. Experimental research of cable insulation accelerated electro-thermal aging was carried out. XLPE-insulated cable samples were exposed to the influence of temperature and voltage above rated. The results of theoretical and experimental research showed that partial discharge dependence on electric field has variable coefficients and requires an additional research, taking all possible influencing factors into account.