An impact-insensitive fiber optic current transformer based on polarization maintaining photonic crystal fiber delay coil

When the polarization-maintaining fiber (PMF) delay coil of a optic current transformer (FOCT) is impacted, external forces on optical fibers and change their birefringence may lead to extra phase errors during propagation signals in fibers. These increase error measurement. In paper, environmental impact mechanisms influencing PMF FOCT were investigated with mathematical model. The method replacing photonic crystal (PCF) as was proposed. Also, relationship between structural parameters air holes linear polarization maintaining PCF subjected stress investigated. also optimized subsequently. Simulated experiments coil, respectively, demonstrated effective resistance after optimization its parameters. measurement FOCTs reduced by approximately 35% respect coil.