High-frequency Partial Discharge Detection by Multicore Fiber-based Hybrid Distributed Reflectometer and Interferometer

The upper frequency of vibration detected by the conventional phase-sensitive optical time-domain reflectometer (Φ-OTDR) is limited by the detection fiber length. In order to achieve long-range sensing and high-frequency partial discharge detection, we propose a scheme of hybrid Φ-OTDR and Mach-Zehnder interferometer (MZI) based on multicore fiber. One of the fiber cores performs the function of Φ-OTDR, and two other cores perform the two arms of MZI. As a proof of concept, the simulation results demonstrate the successful demodulation of high frequency vibration, which shows great potential in the application of partial discharge detection in smart grid.