A Monitoring Method for the Ice Shape and the Freeze-Thaw Process of Ice Accretion on Transmission Lines Based on Circular FBG Plane Principal Strain Sensor

TL;DR

This paper introduces a fiber Bragg grating-based circular array sensor for real-time monitoring of ice shape and freeze-thaw processes on transmission lines, improving ice accretion detection and control.

Contribution

It develops a novel plane principal strain sensing method combined with a neural network for accurate ice process state detection on transmission lines.

Findings

Achieved synchronous strain monitoring across the transmission line cross-section.

Established a relationship between ice mass, shape, and bending strain.

Neural network model with 91.23% accuracy for ice process classification.

Abstract

As a key infrastructure for China's "West-to-East Power Transmission" project, transmission lines (TL) face the threat of ice accretion under complex microclimatic conditions. This study proposes a plane principal strain sensing method based on a fiber Bragg grating circular array, achieving synchronous monitoring of 6 strains (ranging from -2000 to 2000 {\mu}{\epsilon}) across the TL cross-section. Through finite element simulation experiments, a mapping relationship between the bending of TL and the plane principal strain has been established. After completing the sensor calibration, an experimental platform for the freeze-thaw process of ice accretion on the TL was built. The relationships between ice mass and bending strain, as well as the ice shape on the TL cross-section (C-shaped and circular ice) and plane principal strain, were studied. Furthermore, a BP neural network model was developed to determine the 4 states of the icing process (no ice/freeze/stable/thaw), achieving an accuracy of 91.23%. This study provides effective monitoring of the freeze-thaw process of ice accretion on the TL, offering important technical support for the prevention and control of ice accretion in power grid.