New electrical connection technology for covered overhead distribution lines

CEMIG, the Power Company of Minas Gerais State, Brazil, decided to apply just aerial spacer cable system in its urban distribution lines, aiming at reducing operational costs and increasing reliability. The low outage level in such a system is a result of an appropriate design of line joined to the application of materials and equipment of high technology. Since the electrical connections are one of the most critical points, the wedge connector for spacer cable lines was specified. Considering the design concept of CEMIG´s spacer cable system that it should not present noninsulated points, susceptible to cause outage, it was also decided that the connectors might present a protective cover, compatible with the polymeric material of covered conductor. Therefore, CEMIG and AMP do Brasil, a manufacturer of electrical and electronic connectors, promoted a partnership to develop a connection system to be applied in medium voltage overhead covered cables. This paper describes the development of the connector-cover concept, the cost analysis, the involved laboratory tests and the results of the first applications performed on the lines, in field conditions