MV Underground Power Cable Joints Premature Failures

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. To face this reality, the Italian Regulatory Authority for Energy, Networks and the Environment (ARERA), established new more stringent rules to maintain high standards of power quality services also through more resilient electrical system. For this reason, there have been established very ambitious benchmark values for the key performance indicators, normally used to evaluate the quality of electric service. With the aim to increase the resilience of the distribution electrical networks, the DSOs are studying and developing new grid operations with improved assets adopting also advanced electrical technologies. For this reason, in the last decades were developed medium voltage cable joints much easier and faster to install. These joints can make the system more vulnerable for possible imperfections introduced during the construction phase for unperfect manpower and for the complexity of the operations.

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