Influence factors on the dielectric loss factor tan d of XLPE- insulated medium voltage cables

As a consequence of the grids load increment by renewable energy sources as well as decentralized feed-in, the knowledge of the condition of equipment insulation is essential for a reliable energy supply. The dissipation factor or dielectric loss factor tan ? is one of the most important criteria to assess the insulation condition of electrical equipment. However, a measurement of the dielectric loss factor tan ? at a fixed frequency is usual-ly inappropriate in order to describe the complex processes which occur during the age-ing of XLPE insulation material [1]. Moreover, the reproducibility of the loss factor measurement is not feasible thus lead to false results. By measuring the dielectric loss factor tan ? over a wide frequency range, different aging processes can be analyzed due to…