Influence of Polarization Crosstalk of Y Branch Loop on Scale Factor in Fiber Optic Current Sensor

The influence of polarization crosstalk of Y branch loop on scale factor is analyzed in detail. In the Y branch loop, the scale factor is affected by only the output alignment angle of the PBS. The experiment result shows the range of output alignment angle of the PBS should not exceed from 0.2 to 2.5 over a range from - 40°C to 70°C which corresponds to angle 1.8 at room temperature to make sure the measurement accuracy within ±0.2% from 0 to 100kA.