A 3-Phase Current Transducer based on microfluxgate sensors

Abstract

Novel 3-phase DC/AC current transducer for 3-phase current lines is based on 8 integrated fluxgate sensors. Using full information from each sensor rather than gradiometric pairs, we suppress crosstalk between individual phases and external magnetic fields up to the 4th order gradients. The suppression of external currents at a distance of 1 m is 90 dB. The main advantage of the used microfluxgates is excellent temperature stability allowing operation outside the laboratory: the achieved temperature coefficient of the sensitivity is 50 ppm/K, and the offset stability is 1 mA/K. These values are 20-times better than temperature stability achievable with current transducers sensors based on Hall sensors and magnetoresistors.