Contactless current detection with GMR sensors based on an artificial antiferromagnet (AAF) subsystem

摘要

The advantages of the newly developed giant magneto-resistive (GMR) sensor schemo based on artificial antiferromagnetic (AAF) subsystem which was already demonstrated in angle detection, also promises a successful application in contactless current sensing. Wheatstone bridge structures were formed by combining sensors with opposite response characteristics. The sensor linearity was improved by an additional bias field influencing the slope and the maximum range of the signal curve. In our contactless sensing device, currents up to 40 A were measured reliably. Depending on the measuring range, excess currents up to 10 times of the nominal range do not change the sensitivity and bridge offset of the sensor.