A current-measuring transducer device has a current transducer for measuring an electric current along a conduction path. The current transducer has a magnetic field-sensitive element for converting the magnetic field resulting from the current flow along the conduction path into at least one physical variable and a measuring device for measuring the physical variable. The current transducer device has a coil arrangement with at least one coil for simulating the magnetic field resulting from the current flow along the conduction path. There is also described a method for calibrating a corresponding current transducer and a computer program product for performing the calibration method.

An optical fiber winding for measuring current circulating through a conductor. The optical fiber winding includes a first helically wound optical fiber cable and a second helically wound optical fiber cable. The first helically wound optical fiber cable is twisted about its longitudinal axis in a first twist direction, and the second helically wound optical fiber cable is twisted about its longitudinal axis in a second twist direction, the first twist direction being opposite the second twist direction. Each of the first and second helically wound optical fiber cables making contact with one another at multiple locations along their length. Due to the first and second helically wound optical fiber cables making contact with one another and being twisted in opposite directions, counteracting forces exist where the first and second helically wound optical fiber cables contact one another to resist an untwisting.

An optical fiber winding for measuring current circulating through a conductor. The optical fiber winding includes a first helically wound optical fiber cable and a second helically wound optical fiber cable. The first helically wound optical fiber cable is twisted about its longitudinal axis in a first twist direction, and the second helically wound optical fiber cable is twisted about its longitudinal axis in a second twist direction, the first twist direction being opposite the second twist direction. Each of the first and second helically wound optical fiber cables making contact with one another at multiple locations along their length. Due to the first and second helically wound optical fiber cables making contact with one another and being twisted in opposite directions, counteracting forces exist where the first and second helically wound optical fiber cables contact one another to resist an untwisting.

A current sensor of a detection target current using a shunt resistor includes: a resistance value correction circuit having: a correction resistor; a signal application unit that applies an alternating current signal to a series circuit of the shunt resistor and the correction resistor; a first voltage detection unit that detects the terminal voltage of the shunt resistor; a second voltage detection unit that detects a terminal voltage of the correction resistor; and a correction unit that calculates the resistance value of the shunt resistor based on a first voltage detection value by the first voltage detection unit and a second voltage detection value by the second voltage detection unit, and corrects the resistance value for current detection based on a calculated resistance value of the shunt resistor.

A magneto-optical sensor for sensing a current flowing through a conductor includes a light source capable of providing a linearly-polarised optical beam, and a polarisation analyser configured to perform a differential measurement of two polarisation components of the linearly-polarised optical beam having travelled along an optical path arranged between the light source and the polarisation analyser. The optical path forms a closed trajectory around the conductor. The sensor comprises a cell containing an atomic gas arranged along the optical path.

A fiber-optic interferometer is designed to receive and propagate a first single-mode wave along a first optical path and, respectively, a second single-mode wave along a second optical path, the second optical path being the reverse of the first optical path, and to form a first output wave and, respectively, a second output wave, having a modulated phase difference Δϕ.sub.m(t). According to the invention, the modulated phase difference Δϕ.sub.m(t) is equal to sum of a first periodic phase difference Δϕ.sub.π(t) having a level equal to ±π, a second periodic phase difference Δϕ.sub.alpha(t) having a level equal to ±alpha and a third periodic phase difference Δϕ.sub.beta(t) having a variable level between −beta and +beta, said modulated phase difference Δϕ.sub.m(t) comprising per modulation period T at least eight modulation levels among twelve modulation levels and said modulated phase difference between such that: Δϕ.sub.m(t+T/2)=−Δϕ.sub.m(t).

A measuring device measures an electrical current and contains a light source for generating a polarized primary light signal for feeding into a Faraday sensor unit, and a detector for detecting a secondary light signal provided by the Faraday sensor unit and polarization-altered in relation to the primary light signal. An optical-electrical compensation element, by which the polarization alteration of the secondary light signal can be compensated via an opposite polarization alteration, and a measurement signal, according to the opposite polarization alteration, for the electrical current can be deduced. A method for measuring an electrical current by use of the measuring device is further disclosed.

It is proposed to use a spun birefringent fiber for a current sensor or magnetic field sensor. The fiber has a birefringence that increases with temperature. In this case, the temperature dependence of the fiber's sensitivity to magnetic fields counteracts the temperature dependence of the fiber's Verdet constant, which allows to design current and field sensors that have reduced temperature dependence.

Optical techniques and sensor devices for sensing or measuring electric currents and/or temperature based on photonic sensing techniques in optical reflection modes by using optical dielectric materials exhibiting Faraday effects are provided in various configurations. The disclosed optical sensing technology uses light to carry and transmit the current or temperature information obtained at the sensing location to a remote base station and this optical transmission allows remote sensing in various applications and provide a built-in temperature calibration mechanism to enhance the measurement accuracy in a range of different temperature conditions.

A glass ring for current measurements includes a glass body, which can be disposed around an electrical conductor and has a light entry surface and a light exit surface. The glass ring allows light which enters the glass body through the light entry surface to circulate completely around the conductor in the glass body by reflection on external sides or outer faces of the glass body, the light exiting from the glass body on the light exit surface. The glass ring is formed of a monolithic glass body. A method for optical current measurement includes using a current flow in an electrical conductor to generate an electromagnetic field around the conductor, by which a polarization of a light beam in the glass ring around the conductor, in particular with a plane perpendicular to the longitudinal axis of the conductor, is changed as the light beam circulates around the conductor.