Surface preparations on MV-sized cable ends for ramped DC breakdown studies

The rising demand for HVDC crosslinked polyethylene (XLPE) cable systems has put many novel products and solutions on the market within the recent years. In order to assess electrical performance of physical interfaces, DC breakdown studies of XLPE cable samples have been performed. For these samples, the surface of the XLPE in the cable ends has been modified using different techniques. Besides changing the surface preparation method, also the impact of the test conditions has been studied. A slowly ramped DC voltage has been used in order to study the breakdown characteristics for the samples. A great impact on breakdown voltage was found depending on which surface preparation was used. This highlights the fact that interfaces indeed play an important role for HVDC applications.