Design and experimental analysis of a DC to 1 MHz closed loop magnetoresistive current sensor

This paper presents the improvement of a commercially available current sensor based on the anisotropic magneto-resistive effect for applications requiring high bandwidth current measurement such as high switching frequency single-phase and three-phase unity power factor PWM rectifier systems. The sensor concept is of special interest as it could be packaged into compact power processing units and integrated power electronic modules. In this paper the anisotropic magneto-resistive effect, as well as the analog interface electronic for signal conditioning for integrated current sensing are discussed. The sensor functional principle, the advantages and limitations are shown in detail. The measured sensor characteristics are also shown. Finally, improvements are discussed which involves further reduction of the size and the offset calibration procedure