This guide is applicable to The prediction and early warning of icing on overhead transmission lines (OHLs) in micro-topographic areas is covered in this guide. Criteria for identifying micro-topographic areas and methods for predicting the icing thickness of OHLs is presented. This guide aims to provide guidelines for the observation, monitoring, prediction, early warning, and melting of ice on OHLs in micro-topographic areas, serving as references for anti-icing design and maintenance of OHLs in icing-prone areas.

This guide involves online monitoring of the ice on overhead lines (OHL), weather forecasting, terrain identification, and icing prediction. It can serve the high-precision demands of forecasting line icing in specific micro-topographic areas during the design, operation, and maintenance of OHLs. This guide can also provide references for other industries like the communications industry.

This guide intends to provide basic principles and recommended method to predict icing on overhead lines in micro-topographic areas so as to help ensure secure operation of OHLs in the winter. Based on the results of online monitoring, microtopography identification and meteorological forecast, this guide can provide references for early warning of icing on OHLs, for selecting the best time of ice melting and for assessing icing risks to facilitate the design of OHLs in icing-prone areas.