Ricerc@Sapienza

In the last years, the frequency and the intensity of adverse meteorological conditions are on the rise and climate changes have the potential to affect negatively the electrical systems in many different ways. Local or extended electrical outages have been and are caused by extremely severe negative meteorological events of different nature, like strong wind, wet snow, heavy rain and heat waves. Of course, such interruptions of electrical system affect also critical infrastructures with a negative impact on all the human and industrial activities.

MV underground cable systems are one of the main assets in electrical distribution infrastructures in densely populated urban areas. Experience of several distribution operators (DSOs) has shown an increasing number of failures of MV underground cable joints in the summer period. e-distribuzione, the main Italian DSO, and the University of Roma “La Sapienza” have investigated the causes of these joints failures, ran a temperature measurement campaign on cable joints and performed experimental inspections on both failed and not-failed cable joints.

An optimized system management of a commercial and industrial power system must take care of the actual operational and energetic duty of the power system distribution. A procedure based on the Arrhenius model of the Thermal Aging of Insulating Materials allows introducing the relative time coefficient (RTC) and promoting a heuristic method, as a rule of thumb, to estimate the life loss and the residual useful life for insulated power cables.