The Research Of Fault Detection Technology On Traction Power Line Of Beijing Urban Railway

With the Beijing urban railway buses increasing, its functions in Beijing transport system are also prominent. People focus their eyes on the point of urban railway security and stabilization. As a weakness part, traction line of power supply has been the main point of research and detection.Because permanent fault and transient fault can't be distinguished by the present protection mode, transmission line protection is compelled to deal with reclosure blindly, which bring unnecessary secondly damage to the power equipment and fault line. To solve the problem, a protection project based on fault traveling waves is brought forward in this paper, which can correctly identify the fault qualities and give a pulse signal to reclosure device, this ensure the reclosure's efficient action.There are some attributions: firstly, people can understand the fault traveling waves feature and transmission characteristic on power supply line in the paper. Secondly, based on the traveling waves feature, the mother wavelet choice and construction theories are been put forward by author, and validate that cubic dyadic spline symmetrical wavelet about zero is perfectly fitted in with fault traveling waves signals, connected with singularity theory and wavelet transform maximum modulus, the protection project presents the fault location ways, extracts the different quality feature vectors of traveling waves, give the frequency response characteristic of traction power supply line. Thirdly, the fault feature vectors are classified correctly based on artificial neural nets, the...