Current sensor adopting differential coil structure

The invention relates to a current sensor adopting a differential coil structure, comprising a primary current carrying fluid, a primary current sensing unit, a compensation winding, a double-shielded twisted pair, a copper bar, a primary conductor, hollow coils, a loop line, a framework, and an aviation plug. The primary current carrying fluid penetrates through the center of the primary current sensing unit. A metal shielding shell of the compensation winding, a shielding layer of a signal transmission line and a metal part of the aviation plug constitute a whole to improve the signal-to-noise ratio of secondary signals. The role of the hollow coils is to improve the noise immunity of a power-frequency magnetic field. According to the invention, the internal structure of an original hollow coil is improved, a loop line is added to the coil, and two hollow coils of identical structure and performance parameters are made. The interference of an external magnetic field is offset by a differential structure connected in series to a dotted terminal so as to enable the precision of secondary output to meet the requirement of class-0.2 electric energy metering.