A Centimeter Resolution GIS Insulator Strain Distribution Measurement Method Based on OFDR

We proposed a centimeter-resolution insulator strain measuring system based on the optical frequency domain reflectometry to achieve hundreds points distribution measurement. The details of the optical fiber arrangement and signal processing algorithm to obtain the strain distribution on an insulator is presented. A calibration experiment based on a uniform strength beam was carried out to determine the strain sensing factor. Hydrostatic test results demonstrate the accomplishment of 210 points strain distribution measurement with a 1-cm spatial resolution using the proposed system on a 126-kV insulator. Then, the strain distribution on the whole insulator is presented, which is hardly to realized using the conventional strain gauges. The proposed centimeter resolution insulator strain distribution measurement system is suitable for more comprehensive epoxy insulator manufacture processes studies.