Actual Problems Of The Distribution Cable Networks In Germany - Ageing And Structural Impact On The Reliability

This paper provides a synthetic analysis of the actual problems concerning development of the modern electric underground distribution systems. Using randomly chosen 10 kV city network as the example, detailed reliability analysis is performed revealing the problematic issues. Ageing of the assets and unfavorable structural configurations (including unique busbar protection and extended 'inner rings' structures) have significant impact on the system reliability and as such they are demanding serious maturing. The paper considers different network development scenarios and compares the achieved reliability results, which, at the end of the day, may lead to the most beneficial solution.