A current transformer arrangement, and method, include a current sensor for producing a sensor output voltage that is proportional to the input current flowing in a conductor; a first processing branch including a voltage calculating device for calculating the effective voltage value of the sensor output voltage; a second processing branch including a polarity detecting device having an input terminal connected with the current sensor output terminal to produce a polarity signal having one polarity when the conductor input current is either an alternating current, a hybrid current, or a direct current flowing in one direction, and the opposite polarity when the conductor input current is a direct current flowing in the opposite direction; and a multiplier device for modifying the effective voltage value to produce a signed effective voltage having a polarity corresponding with the polarity of the polarity signal. A modifying circuit modifies the signed effective voltage.

A current transformer arrangement, and method, include a current sensor for producing a sensor output voltage that is proportional to the input current flowing in a conductor; a first processing branch including a voltage calculating device for calculating the effective voltage value of the sensor output voltage; a second processing branch including a polarity detecting device having an input terminal connected with the current sensor output terminal to produce a polarity signal having one polarity when the conductor input current is either an alternating current, a hybrid current, or a direct current flowing in one direction, and the opposite polarity when the conductor input current is a direct current flowing in the opposite direction; and a multiplier device for modifying the effective voltage value to produce a signed effective voltage having a polarity corresponding with the polarity of the polarity signal. A modifying circuit modifies the signed effective voltage.

A sensor of electric current including a fiber (1) from a soft magnetic material with a uniform cross-sectional area and uniform magnetic properties along its whole length, equipped with an excitation coil (2) wound on said fiber (1) with a uniform winding density along the substantially whole length and possibly equipped with a sensing coil (3) wound on said fiber (1) with uniform winding density along the substantially whole length, where said fiber (1) ends are mechanically joined to form a loop enclosing the measured current carrying conductor (4) by said fiber (1), wherein said excitation coil (2) is connected to the current output of a current source (5) through a current transducer (6) generating a current signal corresponding to the excitation current flowing through said excitation coil (2) wherein the sensor is equipped with a voltage transducer (7) generating a voltage signal corresponding to the voltage on the possibly present sensing coil (3) or on the excitation coil (2) wherein said voltage signal and said current signal are fed into a processor unit (8). The present disclosure also relates to a method for electric current measurement using said sensor.

The invention relates to a method (100) for detecting faults in a LVDC electric line (500) characterised in that it comprises the following steps: acquiring (101) a first detection signal (V.sub.LOW) indicative of low-frequency components of an unbalancing current (I.sub.G) between a plurality of conductors of said electric line, said first detection signal being obtained by means of a low-pass filtering of a corresponding measuring signal (V.sub.M1) indicative of said unbalancing current; acquiring (102) a second detection signal (V.sub.HIGH) indicative of high-frequency components of an unbalancing current (I.sub.G) between a plurality of conductors of said electric line, said second detection signal being obtained by means of a high-pass filtering of a corresponding measuring signal (V.sub.M2) indicative of said unbalancing current; obtaining (103) a third detection signal (RT) by calculating the ratio between said first and second detection signals (V.sub.LOW, V.sub.HIGH); checking (104) whether a DC current (I.sub.F) is present by comparing said third detection signal (RT) with a first threshold value (TH1).

In a further aspect, the invention relates to an electronic device (1) including processing means for carrying out said method.

The invention relates to a method (100) for detecting faults in a LVDC electric line (500) characterised in that it comprises the following steps: acquiring (101) a first detection signal (V.sub.LOW) indicative of low-frequency components of an unbalancing current (I.sub.G) between a plurality of conductors of said electric line, said first detection signal being obtained by means of a low-pass filtering of a corresponding measuring signal (V.sub.M1) indicative of said unbalancing current; acquiring (102) a second detection signal (V.sub.HIGH) indicative of high-frequency components of an unbalancing current (I.sub.G) between a plurality of conductors of said electric line, said second detection signal being obtained by means of a high-pass filtering of a corresponding measuring signal (V.sub.M2) indicative of said unbalancing current; obtaining (103) a third detection signal (RT) by calculating the ratio between said first and second detection signals (V.sub.LOW, V.sub.HIGH); checking (104) whether a DC current (I.sub.F) is present by comparing said third detection signal (RT) with a first threshold value (TH1).

In a further aspect, the invention relates to an electronic device (1) including processing means for carrying out said method.

Provided is a planar transformer, and more particularly, a planar transformer including: a plurality of primary coil elements included on a flat plate and laminated together; and a plurality of secondary coil elements included on the flat plate and having an induced current generated by the primary coil elements, wherein the plurality of secondary coil elements are respectively disposed above and below the primary coil element.

Provided is a planar transformer, and more particularly, a planar transformer including: a plurality of primary coil elements included on a flat plate and laminated together; and a plurality of secondary coil elements included on the flat plate and having an induced current generated by the primary coil elements, wherein the plurality of secondary coil elements are respectively disposed above and below the primary coil element.