Ice and the Wire Systems of a Transmission Line

摘要

The two distinctive processes of precipitation icing (freezing rain) and in-cloud icing can present different problems to a transmission line engineer. The first part of this discussion focuses on the difficulties and uncertainties of setting the necessary and sufficient freezing rain unit ice loads for the wires, as there seems to be inadequate truly factual data of past large storm events. The in-cloud icing problems arise when the uneven rime or ice deposits typical of mountainous terrain combine with span variations also typical of the same terrain and unexpected failures result. Design guidance is offered for the in-cloud icing problems but the writer is uncertain of the methods to be used to solve the problems, as the sees them, of determining the true ice load values of a freezing rain event.