Research On Corona Characteristic And Altitude Correct For Corona Inception Voltage Of Transmission Line

Building UHV transmission project in high altitude region of western China, corona discharge is more serious than plain. It is important to research on corona onset characteristics of conductors at different altitudes for the design of UHV transmission project. Based on optical fiber digital corona measurement system, this paper carry out the corona characteristic tests on four test points of different altitude. With the test data, based on SVM, we get the relational curve about corona loss with the increasing of test voltage, and the forecast function of different altitude may use the same primary function to express. At the same time, when we obtains the corona inception voltage used tangent method and threshold method, in contrast with the errors about GB/T2317.2-2000 and GB/T775.2-2003, they are quite big and the correct effect is not ideal. In the end, the paper propose the exponential formula and the string formula whose effects meet the project requirement and the errors are within±5%.