台风环境下考虑地理高程信息的输电通道结构失效故障概率评估方法

Power transmission corridors are exposed to external environment, hence they are susceptible to be affected by typhoons. In order to improve the reliability of power grids during typhoons, this paper proposes a method employs failure probability assessment of short-time power transmission corridors based on digital elevation information. Firstly, by conducting statistical analysis of all historical typhoons that have occurred in a province situated in Southeastern China since 1949, it proves that in a short time, the simple prediction of typhoon tracks is better than the similarity prediction method commonly used in meteorological stations. It is therefore conclusive to say this simple prediction method is more suitable for power grids to forecast typhoon tracks that are coming within a short time. Secondly, as the probability distribution of predictive error of radius and angle based on simple prediction is sampled by accept-rejection method, the problem of inadequate samples regarding historical data of typhoon tracks is resolved and then it creates the predicted area of typhoon tracks. At the same time, the global geographical elevation information is integrated with the geographic information of the transmission towers. With this geographical information, the wind load of the transmission towers is corrected by the altitude information of the tower. Lastly, this paper proves that the relationship between the wind speed and the failure rate does not work in a simple linear way, but change in mutation. Compared with the failure rate from a linear curve, the failure rate of an exponential curve may better depict the actual loss data of transmission towers. In case study, based on the analysis of the actual data loss in power transmission corridors under the influence of Meranti in 2016, it is verified that this method is effective and can be used pragmatically in an actual system operation.