Study on Detection of Broken Rail Using Impedance Measurement

임피던스 측정을 통한 레일절손 검지에 관한 연구

  • Received : 2017.02.13
  • Accepted : 2017.03.13
  • Published : 2017.04.30


This paper proposes a method to detect rail broken through impedance measurement. In general, broken rails are detected in real time using the track circuit, but the proposed method not only detects the broken rails but also estimates positions of broken areas by measuring the rail impedance. To electrically insulate one side of the rail, parallel resonance is made by adding a capacitor; then, the impedance of the other rail is measured. If the measured impedance has an inductive value, there is no broken area of rail. However if the measured impedance has a capacitive value, the rail is broken. The proposed method is modeled using a transmission line; it is shown that the modeling can estimate the position of the broken rail according to the impedance value. The rail impedance is measured by the proposed method for a 60m simple rail model, and it is verified that the presence of a broken rail changes the rail impedance.


Supported by : 한국철도기술연구원


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