Research Of Transmission Lines Icing Thickness Prediction Model Based On Markov Process

Extreme-weather events become more frequent than ever with the deterioration and anomaly of global climate. Especially in the last few years, serious icing accidents happened in southern China, which caused power failure and seriously affected residents’daily life, even with huge economic losses. The icing on transmission lines has become social concerns, and made electrical workers to pay more attention to the accident. Meanwhile, development of high voltage transmission lines has become an inevitable tendency for the uneven energy distribution of our country, especially the UHV AC and UHV DC transmission line projects, which are supported by the government. Because of the large transmission capacity, long transmission distance, and complicated environment along lines, icing accidents are more likely to occur under that circumstance and once happened, the consequence could be more serious. Therefore, scholar of home and abroad proceeded a great number of research on the icing thickness on transmission lines.This paper mainly research on the probable values of the icing thickness on transmission lines in the future, by building a medium-and-long term prediction model and a short term prediction model in prediction of icing thickness on transmission lines, and built a platform to predict icing thickness on transmission lines. According to different prediction objects, icing thickness prediction models can be classified into two generic groups:medium-and-long term prediction model and short term prediction model. The medium-and-long term prediction model is used during line-designing to avoid the area where icing could easily or seriously happen. For the lines that have to pass through the icing fields, the towers and lines must be consolidated during designing. For the transmission lines that have already been working, designers should decide whether to rebuild them or not based on the prediction results. The annual maximum of icing thickness is used as basic data to predict the annual maximum of icing thickness in the future based on fuzzy Markov theory. The short term prediction model is used to judge if the icing thickness exceeds the load of lines, for the purpose of scheduling duty work, patrolling lines, ice melting and deicing work. In view of that the powerful impacts of climate are impossible to ignore, multi-variable grey model is used for prediction and modification methods are proposed to solve that problem. Through the validation with relevant icing data, the prediction results agree well with the actual measurement data. In the end, a platform to predict icing thickness on transmission lines is built based on engineering practice, to make it easier for the worker to operate, and finally raises efficiency.