An exemplary embodiment of a sensor system includes a magnet system which is designed to generate a magnetic field. Furthermore, the sensor system includes a first magnetic field sensor which is movable in a first direction relative to the magnet system and has a first distance from the magnet system in a second direction perpendicular to the first direction. The sensor system also includes a second magnetic field sensor which is movable in the first direction relative to the magnet system and has a second distance from the magnet system in the second direction, the second distance being greater than the first distance.

A compass includes a magnetic sensing element in the form of a coil surrounding magnetic material. Electric current is supplied to the coil in opposite directions, depending on the state of switches operated at times T.sub.0, for a first direction, and T.sub.5, for a reverse current direction. A voltmeter measures voltages across the coil, namely at least V.sub.1 at time T.sub.1, after T.sub.0, and V.sub.2 at time T.sub.2, after T.sub.5, with T.sub.1−T.sub.0=T.sub.2−T.sub.5=predetermined ΔT. A processor indicates V.sub.1−V.sub.2, the magnitude and sign of which indicate the strength and direction of the earth's magnetic field respectively.

A compass includes a magnetic sensing element in the form of a coil surrounding magnetic material. Electric current is supplied to the coil in opposite directions, depending on the state of switches operated at times T.sub.0, for a first direction, and T.sub.5, for a reverse current direction. A voltmeter measures voltages across the coil, namely at least V.sub.1 at time T.sub.1, after T.sub.0, and V.sub.2 at time T.sub.2, after T.sub.5, with T.sub.1−T.sub.0=T.sub.2−T.sub.5=predetermined ΔT. A processor indicates V.sub.1−V.sub.2, the magnitude and sign of which indicate the strength and direction of the earth's magnetic field respectively.

A method, device, and system for detecting a current leak in a traction power rail. Magnetic or electrical properties of the rail are measured. The measurements are performed using a rail instrument that senses the properties around the rail at various times while the instrument is being moved down the rail, such as using a cart or train. The rail instrument may be a flux concentrator or open Rogowski coil. The locations of the rail, about which the readings are taken by the rail instrument, may be determined and correlated with the measurements themselves. The method may comprise measuring the magnetic field of the rail along a length of the rail, and identifying a leak based on differences between the magnetic field measurements. The system may comprise a cart comprising the rail instrument and a location instrument.

A method, device, and system for detecting a current leak in a traction power rail. Magnetic or electrical properties of the rail are measured. The measurements are performed using a rail instrument that senses the properties around the rail at various times while the instrument is being moved down the rail, such as using a cart or train. The rail instrument may be a flux concentrator or open Rogowski coil. The locations of the rail, about which the readings are taken by the rail instrument, may be determined and correlated with the measurements themselves. The method may comprise measuring the magnetic field of the rail along a length of the rail, and identifying a leak based on differences between the magnetic field measurements. The system may comprise a cart comprising the rail instrument and a location instrument.

An active shield magnetometry system comprises at least one magnetic field actuator configured for generating an actuated magnetic field that at least partially cancels an outside magnetic field, thereby yielding a total residual magnetic field. The active shield magnetometry system further comprises a plurality of magnetometers respectively configured for measuring the total residual magnetic field and outputting a plurality of total residual magnetic field measurements. The active shield magnetometry system further comprises at least one feedback control loop comprising at least one optimal linear controller configured for controlling the actuated magnetic field at least partially based on at least one of the plurality of total residual magnetic field measurements respectively output by at least one of the plurality of magnetometers.

A current-sensing system includes a conductor for carrying a first electrical current generating a first magnetic field. A device, spaced from the conductor by a clearance, includes a semiconductor integrated circuit die in a package. The semiconductor integrated circuit die includes at least one elongated bar of a first ferromagnetic material magnetized by the first magnetic field; a sensor comprising a first coil wrapped around the at least one elongated bar to sense the bar's magnetization; and an electronic driver creating a second electrical current flowing through a second coil wrapped around the at least one elongated bar generating a second magnetic field to compensate the at least one bar's magnetization. The package has a first outer surface free of device terminals. A discrete plate of a second ferromagnetic material is positioned in the clearance and is conformal with the first outer surface of the package.

Fluxgate current transducer including a fluxgate device comprising a saturable soft magnetic core and an excitation coil, and a processing circuit comprising a control circuit and a voltage generator connected to the control circuit for generating an alternating current in the excitation coil, the voltage generator generating a voltage oscillating between a maximum positive voltage (+U) and a maximum negative voltage (−U) configured to alternatingly saturate the soft magnetic core. The signal processing circuit comprises an overload circuit portion connected to the control circuit, configured to generate overload currents through the excitation coil over time windows (Tn) after detection of the excitation coil current reaching positive and negative threshold currents (+S3, −S3) representative of saturation of the magnetic core, during at least one of a plurality of alternating voltage periods (P).

Fluxgate current transducer including a fluxgate device comprising a saturable soft magnetic core and an excitation coil, and a processing circuit comprising a control circuit and a voltage generator connected to the control circuit for generating an alternating current in the excitation coil, the voltage generator generating a voltage oscillating between a maximum positive voltage (+U) and a maximum negative voltage (−U) configured to alternatingly saturate the soft magnetic core. The signal processing circuit comprises an overload circuit portion connected to the control circuit, configured to generate overload currents through the excitation coil over time windows (Tn) after detection of the excitation coil current reaching positive and negative threshold currents (+S3, −S3) representative of saturation of the magnetic core, during at least one of a plurality of alternating voltage periods (P).

According to an embodiment of the present disclosure, an integrated circuit includes: at least one sensing element configured to generate a sensed signal responsive to an electrical or magnetic phenomenon; an analog-to-digital converter configured to convert the sensed signal into a digital signal; and a digital processor configured to detect a target frequency of the electrical or magnetic phenomenon by iteratively applying a first real-valued coefficient to samples of the digital signal using real-valued arithmetic.