Transmission line icing thickness detection based on distributed optical fiber sensing and Φ-OTDR

To reduce the impact of transmission line icing on the safety of power grid, this article proposes a transmission line icing thickness detection technology based on distributed optical fiber sensing and Φ-OTDR. Firstly, the fundamental physical characteristics changes of transmission line and the frequency characteristics changes of internal signal under transmission line icing are analyzed. Secondly, this article analyzes the distributed optical fiber sensing signal to obtain the phase difference of Ray-leigh backscatter (RBS) signal by Φ-OTDR. By performing a fast Fourier transform on the phase difference of RBS signal during vibration, we can observe the natural frequency of transmission line. On the basis of the natural frequency relationship before and after icing, transmission line icing thickness can be calculated. Finally, simulation results demonstrate the effectiveness of the proposed technology.