To realize bulk and distant transmission of electricity, ultra high voltage (UHV) AC and high voltage (HV) DC transmission lines have been studied. Their environmental impacts cannot be ignored in the case of pursuing economical transmission lines, and many issues concerning environmental impact have been studied worldwide. In this paper, research activity in Japan on the corona effect, which is strongly related to the conductor design and the determination of conductor height of the lowest energized phase, is described.
展开▼