Development of 275kV Aluminum Conductor XLPE Cable and Connectors

This paper presents the development and evaluation of 275 kV aluminum-conductor XLPE cables and connectors for the planned replacement of Oil-Filled (OF) cables in the Tokyo metropolitan area. Due to rising copper prices, aluminum conductors are being considered as a cost-effective alternative, but they present challenges such as higher electrical resistance, greater thermal expansion, and susceptibility to creep and oxidation. To enable installation within narrow existing troughs, a wire-shielded aluminum conductor cable was developed. The prototype reduced the cable diameter by 11 mm for a 2,500 mm² conductor while maintaining transmission capacity. To achieve reliable cable connections, a compact clamp-type connector using cold spray technology was developed, offering stable contact…