Strain analysis of fiber in layer-stranded OPGW cable based on high spatial resolution BOTDA

Optical fiber composite overhead ground wire (OPGW) cables serve dual roles in power systems as ground wires and communication channels. However, strain-induced degradation can compromise their structural integrity and optical performance. This study examines the strain generation and transfer mechanisms within OPGW cables through finite element analysis and tensile testing, utilizing high-resolution DPP-BOTDA for precise strain measurement. Results reveal a helical strain structure inherent to OPGW cables, superimposed on axial tensile strain. Stress in the fiber core emerges at 80% of the rated tensile strength (RTS), escalating rapidly thereafter, while the strain from the helical structure remains stable as overall strain increases. Notably, the variation in helical strain with increased tensile load is minimal, within 0.04%. These findings enhance understanding of OPGW strain behavior, informing strategies for improved durability and performance.