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Magnetic field sensors based on anisotropic magnetoresistance (AMR) are widely used in many scientific and industrial applications. The AMR sensor sensitivity is superior to Hall probes and size and power consumption is superior to fluxgates. However, the noise properties and the temperature stability of AMR sensors are typically worse than for fluxgates. These properties define the typical applications—less precise vectorial or gradient measurements of the magnetic field within less than ±1 mT range. AMR sensors are typically calibrated for sensitivity, offset, and orthogonality errors. However, there is another important source of error—sensitivity to the magnetic field applied in the perpendicular direction to the measurement axis. This so-called cross-field error is inherent to AMR sensors and can influence the measurements significantly. Flipping (set/reset pulses) and closed-loop operation of the sensor can reduce the cross-field error. In this paper, we present a novel approach using full vectorial compensation of the measured magnetic field resulting in a complete elimination of the cross-field effect. The vectorial compensation provided superior results over alternative approaches that were also evaluated. [ABSTRACT FROM PUBLISHER]

DC/AC yokeless galvanically insulated electric current sensors are required for applications, e.g., in automotive and aerospace engineering, where size, weight, and/or price are strictly limited. A busbar current sensor with differential fluxgate in the hole has 1000 A range and 10 mA resolution. Using an asymmetric shape, we achieved a frequency error below ±3% up to 1 kHz, while keeping high temperature stability and low sensitivity to mechanical misalignments. The 2.5 mA/°C maximum dc drift is four times better than when using an AMR sensor and 1000 times better than when using a Hall sensor. The sensor linearity error is below 0.1%. [ABSTRACT FROM PUBLISHER]

Large dc and ac electric currents are often measured by open-loop sensors without a magnetic yoke. A widely used configuration uses a differential magnetic sensor inserted into a hole in a flat busbar. The use of a differential sensor offers the advantage of partial suppression of fields coming from external currents. Hall sensors and AMR sensors are currently used in this application. In this paper, we present a current sensor of this type that uses novel integrated fluxgate sensors, which offer a greater range than magnetoresistors and better stability than Hall sensors. The frequency response of this type of current sensor is limited due to the eddy currents in the solid busbar. We present a novel amphitheater geometry of the hole in the busbar of the sensor, which reduces the frequency dependence from 15% error at 1 kHz to 9%. [ABSTRACT FROM PUBLISHER]