CONDUCTOR SYSTEMS FOR OVERHEAD LINES - SOME CONSIDERATIONS IN THEIR SELECTION

Reasons for the predominance of aluminum-based conductors are outlined, and the wide available range of such conductors and the properties of each main variant are described. The influence of manufacturing processes in conductor design is set out, and the important role played by greasing is emphasized. These considerations are shown to lead to the selection of particular conductors in each of the voltage bands from low voltage to ultrahigh voltage. Factors discussed include load density and growth, climatic environment, strength, standardization, corrosion, external loading, corona effects and economics. Effects of aeolian vibration, subconductor oscillation and galloping on the choice of conductor and fittings, and on conductor bundle geometry, are discussed. The emphasis in choosing conductors for distribution systems is also discussed and the overriding need for standardization stressed. The need for conductor-material specifications and acceptance testing is recognized. A brief outline of possible future trends in conductor engineering is included.