Extension of performances of medium voltage switching equipment

The liberalization of the electricity market motivates distribution utilities to limit investments for the renewal of equipment and for their maintenance though increasing the system availability and the quality of service. In this frame, Enel Distribuzione S.p.A. has carried out in collaboration with CESI the verification of the possibility to extend the performances of medium voltage switching equipment beyond their design data, with particular reference to: • Pre-fabricated switching equipment with metallic enclosure and air insulation (compact switchboard) whose nominal current has been extended from 1250 to 1600 A; • SF6 circuit breaker 24kV–630A–12.5 kA whose lifecycle capabilities have been checked for a prolonged endurance cycle.