Development of suspension-type arresters for transmission lines

A suspension-type surge arrester has been developed by incorporating ZnO elements into the shed of a conventional suspension insulator. This arrester is realized through the development of new techniques such as high-performance ZnO elements, airtight incorporation of ZnO elements into the shed of a conventional insulator, the protection gap, and pressure relief. Both single units and strings of arresters are subjected to contamination, pressure relief, and other tests to confirm that they satisfy the specifications. Long-term reliability was demonstrated in a long-term outdoor test with energization.<>