The icing of optical fiber composite overhead ground wire (OPGW) seriously threatens the stable operation of electric power communication networks

and affects the operation safety of power systems. Therefore

an icing monitoring scheme combined with Brillouin optical time domain reflectometer (BOTDR) and phase-sensitive optical time domain reflectometer (Φ-OTDR) is designed to instantaneously obtain icing state information of OPGW. According to the mechanical analysis of OPGW

Φ-OTDR mechanism is used to establish the relationship between the optical pulse frequency change and the OPGW strain variation before and after icing

and based on the strain variation

the BOTDR mechanism is used to establish the relationship between the Brillouin frequency shift (BFS) change and the OPGW strain and temperature variations before and after icing

thus the icing monitoring function of OPGW can be achieved by using the relationship among strain variation

temperature variation and icing thickness based on the mechanical properties of OPGW. Meantime

the first-order bidirectional Raman amplification module is introduced into the system to extend the monitoring distance. Finally

the proposed scheme is tested and verified by selecting an OPGW with a length of about 113 km of a 500 kV line. The experimental results show that the proposed scheme can monitor the icing state information such as icing span

icing thickness and length in real time

and realize the icing monitoring for long-distance OPGW.