In China

a considerable scale of DC transmission networks have been built. However

the rapid development and large-scale operation of the DC transmission lines have brought a number of issues in management

of which the lightning prevention is a important but difficult issue. The existing calculation and assessment model cannot effectively reflect real lightning risk of the DC transmission lines owing to its limitation in calculation and lack of lightning data record of single DC transmission line. Therefore

the authors collected a large amount of lightning flashover data to describe the entire lightning damage status of DC transmission lines in China. Further

the data mining technology and sensitive factor analysis are employeed for discovering the lightning damage characteristics of DC transmission lines in order to provide a reference for lightning prevention.