An IEEE survey of US and Canadian overhead transmission outages at 230 kV and above

The Working Group on Statistics of Line Outages was formed in 1981 to develop, implement and summarize the results of a survey of design characteristics with overhead transmission at voltages of 230 kV and above. The survey, distributed in July, 1985, requested the voluntary submission of specific data on overhead lines in service within the period, 1965-1985. The purposes of the effort were twofold: to update earlier surveys (1949 and 1965), and to address a growing need for line outage data to support evolving probabilistic system models for planning and operation. Data were submitted by utilities from all nine NERC/USA reliability regions and by the Canadian Electric Association representing all of Canada. The outage data were pooled and analyzed to produce average statistics which are summarized in this paper.<
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