Detection of the impedance variation for nuclear control cable using time frequency domain reflectometry

In this paper, an impedance change localization for the nuclear control cable using the time-frequency domain reflectometry (TFDR) is proposed. The reference signal is designed by analyzing characteristics of the target cable and capacitive coupler. To be prepared for on-voltage experiment, the reference signal is injected into the target cable via capacitive coupler. The experiment using the TFDR and TDR is carried out to localize the impedance variation spot (0, 30, 50, 70, 90 Ω) in the target cable. Through the experiment, the accuracy of the proposed TFDR system is proved.