Date Added: Jul 2010
The aim of this paper is to establish a reference system of the reliability models which may also be applied for different utilities. Due to the large amount of electrical equipments and the costs of an individual diagnosis in distribution networks, a life assessment of the representative electrical components is necessary. Several models are used to estimate the life time of each component but introduced model can estimate the life time for every component in general. The data of historical failure events from distribution networks is collected and evaluated in a special failure statistic and ageing phenomenology is taken into account. For such a purpose, the relationship between lifetime, electrical stress, mechanical stress and temperature as well as their effects on ageing processes and on reliabilities of electrical components are studied. A review of models of transformer and cables will be introduced for comparison.