The Criterion Of Conductor Ice Accretion Types And The Design Of The Ice Disaster Prevention And Control System

Ice accretion on overhead lines occurs regularly around Hunan province. Based on the past experiences, the Hunan power grid corporation has been taking various schemes and methods including conductor icing monitoring and DC/AC current de-icing to the disaster relieving and prevention. However, several deficiencies such as insufficient measured parameter types, experience based ice accretion types identification, inaccurate de-icing current calculation etc. have been found in these schemes and methods, which not only hamper the relevant analyses and calculations, but also reduce the mobility and reliability of actual operations. In order to solve these problems, and to help the Hunan power grid corporation responding conductor icing event more efficiently, the following works have been done:(1) In order to solve the recognized problem of identifying the ice accretion type through meteorological parameters(existing methods such as roughly identification by a few meteorological parameters or complicated theoretical formulas are either inaccurate or inconvenient in daily applications), a new approach based on the similarity theory and cluster analysis is presented, and the similarity criterion is found towards the ice accretion process on conductor. Then, the clusters which represent typical ice accretion types are successfully extracted from the unlabeled icing data, and the typical criterion value combination of each accretion type is obtained from the clusters. These combinations are proved to be able to act as an accurate and convenient method to determine accretion types from meteorological parameters, and have solved one of the puzzling problems in the area.(2) In order to improve the early warning methods of conductor ice accretion for the Hunan province power grid, a review and comparisons of the achievements on the ice accretion prediction models in nearly 60 years are made, and the most improved models regarding different accretion types are selected in the end. Moreover, various modifications towards the thermodynamics and geometric characteristics of conductor which is used by the South Grid Corporation are discussed and applied to better represent their affections on ice accretion.(3) Nearly 20 years of achievements on conductor de-icing and anti-icing models are reviewed in order to select proper ones to improve the current de-icing and anti-icing methods of the Hunan power grid corporation, and the operative steps of each model is clarified.(4) The framework of the icing disaster prevention and control system is designed, and the system flowchart is given to explain the detail scheme. All functionality related to the meteorological parameter monitoring and measuring, accretion type estimation, accretion weight and size calculation, de-icing method selection, anti-icing calculation, history data display and management, etc. are included, and the system is also capable of cooperating with the existing facilities set by the corporation, which sets a solid foundation to the future software development of the system.