Aimed at DC current deection in high-voltage transmission

a DC optical current sensor based on correction of biasing magnetic film is proposed.Biasing magnetic thin film fixed direction of the magnetic field in garnet material improves measurement precision of sensor

the method that using polarimeter directly detect polarization angle and eliminate effect of preset angle error of the polarization plane on measuring system.Theoretical analysis is carried out on sensor for DC detction

optical path structure of sensor is designed

and sensor is used for DC detction experiment.The experimental results show that sensitivity of sensor can match the required measurement range and output linearity of measurement is high

linear fitting degree is 0.999 53

also repeatability of multiple measurement is good and the error is less than 0.4%.