Basic areas of research preceding design and commissioning of 1200 kV AC power transmission lines: Some key problems and solutions

Abstract In the paper is reported the experience of studies that preceded the planning, construction and operation of 1200 kV lines in Russia and Kazakhstan in the former USSR in areas peculiar to UHV power transmission, including the switching surge dielectric strength of long air gaps, selection of line insulation, profound limitation of resonance and switching overvoltages, environmental effects, corona losses of bundles with eight and more subconductors, radio interference. Both implemented and contemplated alternatives of UHV lines are discussed.