WO2020254017A1

WO2020254017A1 - Current-measuring device and method for producing a current-measuring device

Info

Publication number: WO2020254017A1
Application number: PCT/EP2020/061600
Authority: WO
Inventors: Thomas Rapolder
Original assignee: Lisa Dräxlmaier GmbH
Priority date: 2019-06-17
Filing date: 2020-04-27
Publication date: 2020-12-24
Also published as: DE102019116331A1; CN114008465A; DE102019116331B4

Abstract

The present invention discloses a measuring device (100, 200, 300) for measuring an electric current (150), comprising: - a planar carrier structure (101, 201) having at least two planes (102, 103); - a number of conducting structures (104, 105, 204, 205, 219, 304), each of the conducting structures (104, 105, 204, 205, 219, 304) having a power input terminal (106) and a power output terminal (107) and each of the conducting structures (104, 105, 204, 205, 219, 304) having an opening (108, 109, 308), the conducting structures (104, 105, 204, 205, 219, 304) being arranged one over the other on the carrier structure (101, 201) in such a way that the openings (108, 109, 308) at least partially overlap; and - a differentially measuring current sensor, which has two measuring elements (110, 111, 310), the measuring elements (110, 111, 310) being arranged in different planes (102, 103) of the carrier structure (101, 201) at the position of the at least partially overlapping openings (108, 109, 308). The present invention also discloses a method for producing a measuring device (100, 200, 300).

Description

CURRENT MEASURING DEVICE AND METHOD OF MANUFACTURING A

CURRENT MEASURING DEVICE

Technical area

The present invention relates to a measuring device and a method for producing a measuring device.

State of the art

The present invention is described below mainly in connection with the measurement of currents in vehicles, in particular electric vehicles. It goes without saying that the present invention can also be used in other applications.

In modern vehicles, an electric motor can support the internal combustion engine, for example in hybrid vehicles, or replace it, for example in electric vehicles, to reduce emissions. In order to operate such a vehicle with an electric motor, it is necessary to know the operating state of the overall system from the energy source, for example the battery, power electronics and electric motor, at all times.

For this purpose, different variables can be recorded and / or measured in the system. In particular, the current flowing in the system at different points is an important variable. Depending on the magnitude of the current, it can be measured, for example, with the aid of shunt resistors or sensors that work on a magnetic basis. Contactless current measurement is particularly useful in applications with high currents, for example in the busbars of an electric vehicle. For example, sensors can be used that work on the fluxgate principle.

With such sensors, the exact and permanent positioning of the current sensors is crucial for the accuracy of the current measurement over the entire service life of the sensors.

Description of the invention

An object of the invention is therefore to enable a current measurement with high accuracy using means that are as simple as possible in terms of construction.

The object is achieved by the subjects of the independent claims. Advantageous developments of the invention are given in the dependent claims, the description and the accompanying figures. In particular, the independent claims of one claim category can also be developed analogously to the dependent claims of another claim category.

A measuring device according to the invention for measuring an electrical current has: a planar support structure with at least two levels, for example an upper side and a lower side, a number, ie one or more, of line structures, each of the line structures having a power input connection and a power output connection and wherein each of the line structures has an opening, wherein the line structures on the carrier structure are arranged one above the other, i.e. based on the area of the flat carrier structure, in such a way that the openings at least partially overlap, and a differentially measuring current sensor which has two measuring elements, wherein the measuring elements are each arranged in different planes of the support structure at the position of the at least partially overlapping openings.

A method according to the invention for producing a measuring device for measuring an electrical current has the following steps: providing a two-dimensional support structure with at least two levels, forming a number of line structures each with a power input connection and a power output connection, forming an opening in each of the line structures, arranging the line structures on the carrier structure one above the other in such a way that the openings at least partially overlap, and arranging two measuring elements of a differentially measuring current sensor in different planes of the carrier structure at the position of the at least partially overlapping openings.

The present invention is based on the knowledge that previous sensors for current measurement, for example in busbars, are mechanically very complex to manufacture or have only a low, reproducible accuracy due to the mechanical tolerances. The lower accuracy due to manufacturing tolerances can under certain circumstances be compensated for by a calibration process. However, this is an additional, complex refinement step that should be avoided.

The present invention therefore provides a very simple structure for a measuring device which can be used, for example, in electric vehicles in order to measure electrical currents.

For this purpose, a flat carrier structure is provided, on which two measuring elements of a differentially measuring current sensor are arranged. The carrier structure can, for example, have an upper side and a lower side, on each of which one of the measuring elements is arranged. The carrier structure consequently has at least two levels. The planes can also be viewed as those areas on which the line structures and / or sensor elements can be arranged.

Line structures are also arranged on the carrier structure. The line structures carry the current to be measured in the measuring device. The number and dimensioning of the line structures can be adapted to the current to be measured. For example, a line structure can be arranged on the top and a line structure on the underside of the carrier structure. The line structures can be designed, for example, as copper conductor tracks or conductor tracks made of any other electrically conductive material. The power input connections can be electrically connected to one another. As well the power output terminals can be electrically connected to one another. The individual line structures are consequently arranged electrically in parallel.

Each of the line structures has an opening. The openings are parallel to the surface of the support structure. In a plan view of the support structure, the openings are therefore parallel to the image plane. The openings can have a round or circular, rectangular, oval outer contour or the like.

The line structures are arranged on the carrier structure in such a way that the openings of the individual line structures at least partially or completely overlap. It goes without saying that manufacturing-related tolerances and component tolerances can be included in a complete superposition.

So there is a line structure on top of the support structure and a

Line structure on the underside of the carrier structure, the line structures can be designed to be exactly uniform and run the same in the respective plane on the

Be arranged support structure.

For current measurement, the line structures can be integrated in a busbar, for example in an electric vehicle or a control device of such an electric vehicle. For this purpose, the busbar can be interrupted at the corresponding point and one end of the busbar can be connected to the power input connections of the line structures. The other end of the power rail can be connected to the

Power output connections of the line structures are connected. The entire current flowing in the busbar consequently also flows via the measuring device.

If a current flows through the line structures, a magnetic field forms around the line structures. The magnetic fields that arise within the opening act against each other and are completely canceled out in the exact center of the opening - at least in the case of a symmetrical structure.

The differentially measuring current sensor with the two measuring elements that are arranged in the openings or in the respective plane at the position of the openings, consequently measure the difference between the two magnetic fields at the respective position. This measurement is very robust and largely independent of external interference.

Consequently, with the aid of the measuring device according to the present invention, a high current, for example in an electric vehicle, can be detected very easily and precisely.

Further embodiments and developments emerge from the subclaims and from the description with reference to the figures.

In one embodiment, the planar support structure can be designed as a double-sided printed circuit board with a top and a bottom. In this case, a line structure can be arranged on the top of the printed circuit board and a further line structure can be arranged on the underside of the printed circuit board.

A double-sided circuit board can be made with very simple means. In particular, the line structures can be attached very easily to the top and bottom of the circuit board using circuit board production means.

It goes without saying that any material suitable for the respective application, such as FR4 or ceramic, can be used as the material for the circuit board.

In the production of such a circuit board, one line structure can be produced on the top and one on the bottom. As already explained, the line structures can be designed as conductor tracks. It goes without saying that the material thickness of the conductor tracks can be selected depending on the current to be carried or measured. It is also understood that the line structures can alternatively or additionally have electrically conductive elements which can additionally be applied to the circuit board. For example, solid copper or aluminum wires or the like can be applied to the circuit board.

In a further embodiment, the planar support structure can be designed as a multilayer printed circuit board, also called a multilayer printed circuit board. In this case, the line structures can be arranged distributed in particular symmetrically in the layers of the multilayer printed circuit board. If the carrier structure is designed as a multilayer circuit board, corresponding line structures can be arranged in the individual layers of the circuit board. This means that the current-carrying capacity of the measuring device can be flexibly adapted to the respective application. The current carrying capacity of the measuring device results from the current carrying capacity of an individual line structure multiplied by the number of line structures.

The symmetrical arrangement of the individual line structures in the planes of the support structure leads to a symmetrical magnetic field distribution within the openings. The measurement can thus be simplified, since the individual measuring elements do not have to be adapted to an asymmetrical magnetic field.

In another embodiment, one of the layers can be designed as an information transmission layer. The information transmission layer can, for example, have conductor tracks for contacting the measuring elements.

In particular, when line structures are arranged on the top and bottom of the carrier structure, the information transmission layer can simplify the electrical contacting of the measuring elements. It goes without saying that, for example, wired contacting of the measuring elements is possible in any case. However, due to the information transfer layer, the contacting of the measuring elements can be shifted into the interior of the carrier structure. There are consequently no exposed wires in the measuring device. This makes the measuring device more robust and less prone to errors.

In yet another embodiment, the measuring elements can be designed at least partially as conductor structures in the carrier structure.

It goes without saying that the measuring elements can be designed as discrete components, for example as SMD components. Such measuring elements can, for example, be placed and soldered very precisely on the carrier structure as part of the production of printed circuit boards. Alternatively, for example, individual components of the measuring elements, for example the measuring sensors in the form of measuring coils or measuring lines or the like, can be designed as conductor structures.

For example, a measuring line of a measuring element can be designed as a conductor track in one of the inner layers of a multi-layer printed circuit board. An excitation coil can be formed around the measuring line, for example, with the help of a combination of plated-through holes, also called vias, and corresponding conductor tracks. It goes without saying that further components of the measuring elements, such as (differential) amplifiers, filters and the like, can be attached to the top or bottom of the carrier structure.

In one embodiment, the measuring elements can each be designed to measure a current according to the principle of a fluxgate magnetometer. Such measuring elements can also be called saturation core magnetometers or Förster probes.

The measurement of currents according to the principle of a fluxgate magnetometer is very resistant to external interference. If two such measuring elements are combined to form a differentially measuring current sensor, a very robust and exact measurement of the current can be carried out in the measuring device.

In another embodiment, the measuring elements can each have a measuring axis. The measuring elements can be arranged in such a way that the measuring axis is each at a predetermined angle to the direction of the current flow through the line structures, in particular at an angle of 0 ° or 90 °.

In the measuring device, the individual measuring elements can be arranged in different ways in relation to the direction of the current flow and thus the direction of the magnetic fields generated.

The measuring axis denotes the axis of the highest sensitivity of the respective measuring element. Depending on the arrangement of the measuring axes, the structure of the current sensor in one axis can be susceptible to interference fields, for example if another busbar runs in the vicinity of the measuring device. Accordingly, the measuring elements can be arranged in such a way that this external influence is eliminated or minimized.

It goes without saying that a further pair of measuring elements can also be provided, the measuring axes of which can be arranged, for example, orthogonally to the measuring axes of the first two measuring elements. This means that two current measurements can be carried out and compared with one another in order to identify external interference.

In yet another embodiment, the measuring elements can be arranged offset from one another at a predetermined distance in relation to the surface of the carrier structure.

The measuring elements are thus offset from one another when viewed from above on the surface of the carrier structure. By means of this offset, the distance between the measuring axes or measuring means within the measuring elements can be set exactly. The offset determines the distance between the measuring equipment and the point at which the magnetic fields cancel each other. The greater the distance, the greater the magnetic field to be measured in the respective measuring element. This also increases the difference to be measured and makes the measurement more robust. However, the system saturates earlier and this limits the measuring range.

In a further embodiment, the power input connections of the line structures can be coupled to a first external connection of the measuring device. The power output connections of the line structures can be coupled to a second external connection of the measuring device.

The measuring device can, for example, be integrated directly into a control unit or another circuit within the respective application. For example, the measuring device can be integrated on the circuit board of an inverter or a safety device in an electric vehicle. Alternatively, the measuring device can be provided with corresponding external connections. The shape and nature of these external connections can be adapted to the respective application. For example, the external connections can be designed as soldering lugs or contact sheets that can be welded or contacted by clinching. The measuring device can thus be used very flexibly in different applications.

Brief description of the figures

Advantageous exemplary embodiments of the invention are explained below with reference to the accompanying figures. Show it:

FIG. 1 shows a block diagram of an exemplary embodiment of a measuring device according to the present invention in a top view and a sectional view;

FIG. 2 shows a block diagram of a further exemplary embodiment of a measuring device according to the present invention in a side view;

FIG. 3 shows a detail of an embodiment of a measuring device according to the present invention in a plan view; and

FIG. 4 shows a flow diagram of an exemplary embodiment of a method according to the present invention.

The figures are merely schematic representations and serve only to explain the invention. Identical or identically acting elements are provided with the same reference symbols throughout.

Detailed description

FIG. 1 shows a measuring device 100 in a top view (left) and a sectional view (right) through the middle of the top view (shown by a dashed line). The measuring device 100 has a carrier structure 101. The carrier structure 101 is designed as a two-sided printed circuit board and thus has two planes 102, 103 in or on which further elements of the measuring device 100 can be arranged. In the measuring device 100, a line structure 104, 105 is arranged in each level. A line structure 104 is therefore arranged on the top of the board and a line structure 105 is arranged on the underside of the board. In the top view it can be seen that the line structures 104, 105 have a power input connection 106 and a power output connection 107 (only shown for the upper line structure 104). The individual line structures 104, 105 are on the

Power input connections and the power output connections are electrically coupled to one another and thus arranged electrically in parallel.

The line structures 104, 105 have a widened section between the power input connection 106 and the power output connection 107, in the center of which an opening 108, 109 is arranged. The surface of the carrier structure 101 is accessible through the opening. The line structures 104, 105 are arranged in such a way that the openings 108, 109 overlap in plan view. A measuring element 110, 111 of a differentially measuring current sensor is arranged in the openings on each plane 102, 103.

When the support structure 101 is constructed as a two-sided circuit board, the current 150 to be measured flows past the openings 108, 109 on two sides. Each of the sides thus forms a conductor section through which current flows, around which a magnetic field is formed. The magnetic fields are superimposed within the openings 108, 109 and partially or completely cancel each other out in the center.

The center of the construction of the measuring device 100 lies in the middle of the carrier structure 101. The measuring elements 110, 111 cannot therefore be positioned exactly in this center. Consequently, the measuring elements 110, 111 are each located in areas in which a magnetic field can be measured. This arrangement consequently enables the differential measuring system to be used in the current sensor.

Although not shown separately, it goes without saying that the measuring elements 110, 111 can be contacted, for example, by means of wires or lines. As shown in FIG. 2, in the case of a multilayer printed circuit board, the measuring elements can also be contacted via an information transmission layer. It is further understood that the measuring elements 110, 111 can be coupled to a corresponding energy source and can have an evaluation or computing device or can be coupled to such a device.

FIG. 2 shows a block diagram of a further measuring device 200. The measuring device 200 likewise has a carrier structure 201. The carrier structure 201 is designed as a multilayer printed circuit board and has four prepregs 215, 216, 217, 218. It goes without saying that the term prepregs was chosen here only as an example and that any technology can be used for the production of multilayer printed circuit boards. The four prepregs 215, 216, 217, 218 result in the carrier structure 201 having five levels, the top side, the bottom side and three levels lying between the upper prepreg 215 and the lower prepreg 218. For the sake of clarity, the individual levels are not provided with reference symbols.

The measuring device 200 has three line structures 204, 205, 219. The line structure 204 is arranged on the upper side of the carrier structure 201. The line structure 205 is arranged on the underside of the carrier structure 201. The third line structure is arranged between the inner prepregs 216, 217. It goes without saying that each of the line structures 204, 205, 219 has a corresponding opening for the formation of the magnetic fields. The non-visible measuring elements can be arranged within the openings on the top and the bottom of the carrier structure 201. For contacting the measuring elements, two information transmission layers or planes between prepregs 215 and 216 or prepregs 217 and 218, in which conductor tracks 220, 221, 222, 223 are arranged, are shown as an example. The conductor tracks 220, 221, 222, 223 are each connected to a corresponding connection 224, 225, 226, 227 on the upper side or the lower side of the carrier structure 201 by means of a through-connection. The measuring elements can consequently be contacted or supplied with electrical energy via the connections 224, 225, 226, 227.

FIG. 3 shows a section of a measuring device 300. In FIG. 3, only a section of a line structure 304 of the measuring device 300 is shown. The line structure 304 has an opening 308 in which a measuring element 310 is arranged. In the measuring element 310, the corresponding measuring sensor 330 is shown as an arrow. The measuring sensor 331 of the second measuring element is shown as a dashed arrow. It can be seen that the measuring sensors 330, 331 are arranged at the same distance from the central axis in each case on opposite sides in the opening. The symmetrical arrangement of the measuring sensors 330, 331 enables a very simple implementation of the differential measuring principle. It goes without saying that the measuring sensors 330, 331 can alternatively also be arranged asymmetrically. A corresponding offset correction can be provided in such an embodiment.

FIG. 4 shows a flow chart of an exemplary embodiment of a method for producing a measuring device (100, 200, 300) for measuring an electrical current (150). For easier understanding, the reference numerals for FIGS. 1-3 are retained as references in the following description.

In a first step S1 of the provision, a planar support structure (101, 201) with at least two levels (102, 103) is provided. For example, this can be a printed circuit board made of FR4 material, ceramic or the like. In a second step S2 of the formation, a number of line structures (104, 105, 204, 205, 219, 304) each having a power input connection (106) and a power output connection (107) are formed. In a third step S3 of the formation, an opening (108, 109, 308) is formed in each of the line structures (104, 105, 204, 205, 219, 304). In a fourth step S4 of the arrangement, the line structures (104, 105, 204, 205, 219, 304) are arranged one above the other on the carrier structure (101, 201) in such a way that the openings (108, 109, 308) at least partially overlap. In a fifth step S5, two measuring elements (110, 111, 310) of a differentially measuring current sensor are placed in different planes (102, 103) of the support structure (101, 201) at the position of the at least partially overlapping openings (108, 109, 308) arranged.

It goes without saying that individual steps of the method described can be combined. For example, steps S2, S3 and S4 can be carried out in a single step in the course of a circuit board production.

The two-dimensional carrier structure (101, 201) can be configured, for example, as a double-sided printed circuit board with an upper side and a lower side. A line structure (104, 105, 204, 205, 219, 304) can be arranged on the top of the circuit board and a further line structure (104, 105, 204, 205, 219, 304) can be arranged on the underside of the circuit board.

The planar support structure (101, 201) can alternatively also be designed as a multilayer printed circuit board. The line structures (104, 105, 204, 205, 219, 304) can in particular be distributed symmetrically in the layers of the multilayer printed circuit board.

One of the layers in the multilayer circuit board can also be designed as an information transmission layer. At least conductor tracks (220, 221, 222, 223) for making contact with the measuring elements (110, 111, 310) can be arranged in the information transmission layer. Further conductor tracks, for example for supplying energy to the measuring elements (110, 111, 310) are also possible.

The measuring elements (110, 111, 310) can be designed as discrete elements. However, the measuring elements can at least partially be designed as conductor structures in the carrier structure (101, 201). This is especially the case for the measuring lines or excitation coils if the measuring elements (110, 111, 310) are each designed to measure a current (150) according to the principle of a fluxgate magnetometer.

The measuring elements (110, 111, 310) can each have a measuring axis and can be arranged in such a way that the measuring axis lies at a predetermined angle to the direction of the current flow through the line structures (104, 105, 204, 205, 219, 304). Such an angle can be, for example, an angle 0 ° or 90 °. Furthermore, the measuring elements (110, 111, 310) can be arranged offset from one another at a predetermined distance relative to the surface of the carrier structure (101, 201).

In order to be able to use the measuring device as a dedicated sensor, the power input connections of the line structures (104, 105, 204, 205, 219, 304) can be coupled to a first external connection of the measuring device (100, 200, 300). The power output connections of the line structures (104, 105, 204, 205, 219, 304) can be coupled to a second external connection of the measuring device (100, 200, 300). Since the devices and methods described in detail above are exemplary embodiments, they can be modified in the usual way by a person skilled in the art to a wide extent without departing from the scope of the invention. In particular, the mechanical arrangements and the proportions of the individual elements to one another are merely exemplary.

REFERENCE LIST

100, 200, 300 measuring device

101, 201 support structure

102, 103 level

104, 105, 204, 205, 219, 304 line structure

106 Power input connector

107 Power output connector

108, 109, 308 opening

110, 111, 310 measuring element

215, 216, 217, 218 prepreg

220, 221, 222, 223 track

224, 225, 226, 227 connection

330, 331 Position of the sensor 332 Distance

150 electricity

S1 - S5 process step

Claims

EXPECTATIONS

1. Measuring device (100, 200, 300) for measuring an electrical current (150), comprising: a planar support structure (101, 201) with at least two levels (102, 103), a number of line structures (104, 105, 204 , 205, 219, 304), wherein each of the line structures (104, 105, 204, 205, 219, 304) has a power input connection (106) and a power output connection (107) and wherein each of the line structures (104, 105, 204, 205 , 219, 304) has an opening (108, 109, 308), the line structures (104, 105, 204, 205, 219, 304) on the carrier structure (101, 201) being arranged one above the other in such a way that the openings (108 , 109, 308) at least partially overlap, and a differentially measuring current sensor which has two measuring elements (110, 111, 310), the measuring elements (110, 111, 310) each in different planes (102, 103) of the carrier structure ( 101, 201) at the position of the at least partially overlapping opening ngen (108, 109, 308) are arranged.

2. Measuring device (100, 200, 300) according to claim 1, wherein the planar support structure (101, 201) is designed as a double-sided printed circuit board with an upper side and a lower side, and wherein a line structure (104, 105, 204 , 205, 219, 304) is arranged and a further line structure (104, 105, 204, 205, 219, 304) is arranged on the underside of the circuit board.

3. Measuring device (100, 200, 300) according to claim 1, wherein the planar support structure (101, 201) is designed as a multi-layer printed circuit board, the line structures (104, 105, 204, 205, 219, 304) in particular symmetrically in the Layers of the multilayer printed circuit board are arranged distributed.

4. Measuring device (100, 200, 300) according to claim 3, wherein one of the layers is designed as an information transmission layer and has at least conductor tracks (220, 221, 222, 223) for contacting the measuring elements (110, 111, 310).

5. Measuring device (100, 200, 300) according to one of the preceding claims, wherein the measuring elements (110, 111, 310) are at least partially designed as conductor structures in the carrier structure (101, 201).

6. Measuring device (100, 200, 300) according to one of the preceding claims, wherein the measuring elements (110, 111, 310) are each designed to measure a current (150) according to the principle of a fluxgate magnetometer.

7. Measuring device (100, 200, 300) according to one of the preceding claims, wherein the measuring elements (110, 111, 310) each have a measuring axis and wherein measuring elements (110, 111, 310) are arranged such that the measuring axis in each case predetermined angle to the direction of the current flow through the line structures (104, 105, 204, 205, 219, 304), in particular at an angle of 0 ° or 90 °.

8. Measuring device (100, 200, 300) according to one of the preceding claims, wherein the measuring elements (110, 111, 310) are arranged offset from one another at a predetermined distance relative to the surface of the support structure (101, 201).

9. Measuring device (100, 200, 300) according to one of the preceding claims, wherein the power input connections of the line structures (104, 105, 204, 205, 219, 304) are coupled to a first external connection of the measuring device (100, 200, 300) and the power output connections of the line structures (104, 105, 204, 205, 219, 304) are coupled to a second external connection of the measuring device (100, 200, 300).

10. A method for producing a measuring device (100, 200, 300) for measuring an electrical current (150), comprising the steps:

Providing (S1) a planar support structure (101, 201) with at least two levels (102, 103),

Forming (S2) a number of line structures (104, 105, 204, 205, 219, 304) each with a power input connection (106) and a power output connection (107), Forming (S3) an opening (108, 109, 308) in each of the line structures (104, 105, 204, 205, 219, 304),

Arranging (S4) the line structures (104, 105, 204, 205, 219, 304) on the carrier structure (101, 201) one above the other in such a way that the openings (108, 109, 308) at least partially overlap, and

Arranging (S5) two measuring elements (110, 111, 310) of a differentially measuring current sensor in different planes (102, 103) of the support structure (101, 201) at the position of the at least partially overlapping openings (108, 109, 308).

11. The method according to claim 10, wherein the planar support structure (101, 201) is designed as a double-sided printed circuit board with a top and a bottom and wherein a line structure (104, 105, 204, 205, 219, 304) on the top of the printed circuit board is arranged and a further line structure (104, 105, 204, 205, 219, 304) is arranged on the underside of the circuit board.

12. The method according to claim 10, wherein the planar support structure (101,

201) is designed as a multi-layer circuit board, the line structures (104, 105, 204, 205, 219, 304) being arranged in particular symmetrically distributed in the layers of the multi-layer circuit board, and in particular with one of the layers as

Information transmission layer is formed and at least conductor tracks (220, 221, 222, 223) for contacting the measuring elements (110, 111, 310) in the

Information transfer position can be arranged.

13. The method according to any one of the preceding claims 10 to 12, wherein the measuring elements (110, 111, 310) are at least partially formed as conductor structures in the carrier structure (101, 201), and / or wherein the measuring elements (110, 111, 310) are each designed to measure a current (150) according to the principle of a fluxgate magnetometer, and / or wherein the measuring elements (110, 111, 310) each have a measuring axis and wherein the measuring elements (110, 111, 310) are arranged in such a way that the measuring axis is at a predetermined angle to the direction of the current flow through the line structures (104, 105, 204 , 205, 219, 304), in particular at an angle of 0 ° or 90 °.

14. The method according to any one of the preceding claims 10 to 13, wherein the measuring elements (110, 111, 310) are arranged offset from one another at a predetermined distance relative to the surface of the carrier structure (101, 201).

15. The method according to any one of the preceding claims 10 to 14, wherein the

Power input connections of the line structures (104, 105, 204, 205, 219, 304) are coupled to a first external connection of the measuring device (100, 200, 300) and the power output connections of the line structures (104, 105, 204, 205, 219, 304) are coupled to a second external connection of the measuring device (100, 200, 300).