Study on Feeder Protection Method of Metro Traction Electric Network Considering Oscillation Blocking

The electric energy required by the subway is directly taken from the dc traction network, but the oscillating current in the traction network system frequently causes the mis operation of the feeder protection of the traction network. By studying the difference of oscillation current and short-circuit current waveform characteristics in the system, a new protection algorithm is proposed, and LabVIEW is used as a tool to program software package. By comparing the new algorithm with the existing wavelet packet energy spectrum diagnosis algorithm, the advantages of the new algorithm are shown.