Patent ID: 8884615
Filing Date: 2014-11-11
Classification: B82Y,G01R

Abstract:
1. Sensor unit for the measurement of a current in a conductor comprising at least one magnetoresistive sensor located at a radial distance from the outer surface of the conductor, wherein the conductor has a circular cross-section, wherein the sensor unit comprises at least one auxiliary coil for the generation of a bias magnetic field (H bias ) to the at least one magnetoresistive sensor strong enough for inducing magnetic saturation in the at least one magnetoresistive sensor continuously during the whole current measurement process, wherein the magnetic field generated by the current in the conductor is directly measured by the at least one magnetoresistive sensor, wherein the direction of the bias magnetic field (H bias ) provided by the auxiliary coil is oriented at an angle of 88-92° with respect to the direction of the magnetic field (H curr ) produced by the current in the conductor, wherein the auxiliary coil is provided as one multiturn winding around and coaxial with the conductor, and wherein the at least one magnetoresistive sensor is sandwiched between the conductor and the windings of the auxiliary coil.