PD knowledge rules support for CBM of distribution power cables

It is known that condition based maintenance (CBM) can offer a support in meeting requirements of liberalization processes at power utilities. As a result, based on the information about the actual insulation condition of a cable link, the operation, the maintenance and the replacement can be optimally planned. This contribution discusses, based on advanced PD diagnostic at oscillating voltages, different evaluation methods to assess the insulation condition of cable systems. Based on field experiences, important CBM aspects such as knowledge about ageing processes and failure modes as well as methods to determine the interpretation and knowledge are discussed.