METHOD FOR DETECTING AN ELECTRIC ARC OCCURRING BETWEEN A RAILWAY OVERHEAD CONTACT LINE AND A RAILWAY TRACTION UNIT AND CORRESPONDING DETECTION ARRANGEMENT

摘要

A method for detecting an arc (A, Varc) occurring between a railway overhead contact line (12) carrying DC voltage (Vline) and a pantograph (11a) of a railway traction unit (11) collecting the current (Ip) absorbed or injected by the railway traction unit (11), said pantograph (11a) comprising an input low pass filter operating at a given natural frequency (fN) receiving at its input a voltage (Vp) between the pantograph (11a), in particular the pantograph shoe, and a reference node and said current (Ip) absorbed or injected by the railway traction unit (11) and supplying at its output a filtered voltage (Vdsf) to the railway traction unit (11), said method comprising measuring (110) said voltage (Vp) between the pantograph (11a) and the reference node and said current (Ip) absorbed or injected by the railway traction unit (11) obtaining a measured voltage (Vp,out) and a measured current (Ip,out) respectively, extracting (120; 220; 320) from said measured voltage (Vp,out) an extracted voltage signal (Vbp; Vfi VT) with a delimited spectral portion around a given detection frequency (fdet), extracting (130; 230; 330) from said measured current (Ip,out) absorbed or injected by the locomotive an extracted current signal (Ibp; Ifi IT) with a delimited spectral portion around the given natural frequency (fN), comparing (140; 24Ov, 2401; 340v, 340i) an amplitude of said extracted voltage signal (Vbp; Vfi VT) with a delimited spectral portion and an amplitude of said extracted current signal (Ibp; Ifi IT) with a delimited spectral portion with a respective threshold (thv, thi), verifying (150; 250) if said comparison operation (140) indicates that both the amplitude of the extracted voltage signal (Vbp; Vfi VT) with a delimited spectral portion and the amplitude of the extracted current signal (Ibp; Ifi IT) with a delimited spectral portion are above the respective threshold (thv, thi), and in the affirmative signaling (160) detection (AD) of an arc (A).