Analysis of ice disasters on ultra-high-voltage direct-current transmission lines

Abstract

Ice disaster is one of the biggest natural disasters posing great threat to the safe operation of power grid. With the construction and operation of ultra-high-voltage direct-current (UHVDC) Transmission Project, it is urgent to carry out research on ice-coating and ice-melting of large-section current-carrying conductors to provide technical support for the safe operation of UHVDC transmission project. Researchers have made a large amount of research on small-section conductors. However, these research results for small-section conductors cannot be applied to large-section conductors. Thus, our research team carries out the research on ice-coating and ice-melting of large-section current-carrying conductors under artificial conditions. The typical large-section current-carrying conductor LGJ-630/55 is employed to analyze the ice-coating and ice-melting characteristics of large-section current-carrying conductors with some main factors, including wind, precipitation, temperature, current, and so on. Based on the experiments’ results, we have arrived at several rules of ice-coating and ice-melting of large-section current-carrying conductors. Meanwhile, an improved Ice-melting Model taking account Heat Exchange and Gravity (IMHEG) is proposed in this paper. This IMHEG model is verified to be more proper than the traditional ice-melting model, and can be a useful model for practical application.