Current sensor including core and manufacturing method therefor

Abstract

This current sensor includes: at least one coil including a plurality of via holes formed to pass through an insulating layer and conductor layers of a substrate including the insulating layer and the conductor layers formed on both surfaces of the insulating layer, each via hole having a conductive film formed on the inner wall thereof, and line patterning formed on the conductor layers to connect the plurality of via holes; and a core disposed inside the coil along the central axis of the coil.

Description

Current sensor including a core and method of manufacturing the same

[0001] The present invention relates to a current sensor for measuring current flowing in a power line in a non-contact manner, and more specifically, to a current sensor including a core capable of achieving high sensitivity and low noise characteristics in the commercial frequency band, and a method for manufacturing the same.

[0002] Accurate measurement of current flowing through power lines is a critical factor that enables the maximization of power usage efficiency through the forecasting and analysis of power demand, as well as the protection of the power system through the detection of fault currents and the rapid isolation of the faulted system.

[0003] Current sensors for detecting the current flowing through a conductor under measurement can be classified according to the detection method into a resistance detection method using a shunt resistor and a magnetic field detection method using a magnetic field around the conductor. The magnetic field detection method can be divided into sensors using a current transformer (CT) and sensors using a Hall element.

[0004] Since CT devices utilize the principle of a transformer, they are generally applied to the measurement of AC currents that change over time. When current flows through a wire, a magnetic field is formed around it. When a wire is passed through the inside of a donut-shaped CT, an induced current flows in the CT's coil due to the magnetic field surrounding the wire.

[0005] A Hall element is a device that utilizes the Hall effect, in which an electromotive force is generated in a direction perpendicular to the current and the magnetic field when a magnetic field is applied perpendicular to the current. Sensors utilizing this Hall effect are called Hall sensors, and a detection signal is generated by a change in the magnetic field of a magnetic object.

[0006] A current sensor of the Rogowski coil type, which is another form of magnetic field detection method, measures current by converting the voltage induced in an air-core coil by an alternating magnetic field generated around the measured current. That is, the magnetic field caused by the alternating current flowing in the measuring conductor (primary side) links with the air-core coil, thereby generating an induced voltage in the air-core coil. Since this induced voltage is the time derivative of the measured current, it is passed through an integrator to output a signal proportional to the measured current.

[0007] Another method discloses a current sensor that detects alternating current by placing a sensor unit at a predetermined distance from a power conductor through which alternating current flows, and measuring electromagnetic waves generated in the sensor unit by the induced electromotive force generated by the alternating current flowing in the power conductor (see, for example, Korean Registered Patent Publication No. 10-1981640).

[0008] In order to miniaturize the size of the current sensor, a current sensor disclosed in Korean Registered Patent Publication No. 10-1981640 or a current sensor using a Hall element can be used. However, the current sensor disclosed in Korean Registered Patent Publication No. 10-1981640 has a problem in that the measurement sensitivity is significantly reduced at low current (e.g., 1A or less) because the sensor part is composed of a non-coilable measuring wire placed parallel to the power wire.

[0009] Hall elements have limitations in miniaturization because they require a magnetic core (see, for example, Korean Registered Patent Publication No. 10-0897229). Furthermore, because they are sensitive to magnetic signals, they are vulnerable to noise; unless noise is completely shielded, induced magnetism generated during the active state of adjacent busbars can be introduced as noise, leading to an increase in measurement errors.

[0010] Furthermore, since most magnetic field detection type current sensors have power lines penetrating the core, they cannot be simply mounted on existing power lines and have the disadvantage of requiring a large mounting area.

[0011] In terms of mounting area, a printed circuit board with a CT (Current Transformer) function is described to overcome spatial constraints for mounting on power lines; however, since this targets high-frequency power in the RF (Radio Frequency) band with frequencies ranging from hundreds of kHz to several GHz, current detection is possible even if a metal shield is placed between the power line and the coil to block the electric field (for example, see Japanese Patent Publication No. 2015-200631).

[0012] However, in the case of low-frequency power with a commercial frequency of 50 Hz or 60 Hz, unlike high-frequency power in the RF band, the level of induced current caused by magnetic flux generated in the power line does not differ significantly from the ambient (atmosphere) noise level, so there is a problem that it is not easy to measure the current flowing in the power line through a structure similar to the printed circuit board having CT function described in Japanese Patent Publication No. 2015-200631.

[0013] Therefore, there is a need for a current sensor that ensures sufficient sensitivity in the commercial frequency band while minimizing the influence of external noise and has a compact structure that can be easily mounted on existing power lines.

[0014] The present invention is designed to solve the above problems, and one technical objective of the present invention is to provide a current sensor including a core that can maintain high sensitivity during commercial frequency current measurement while minimizing the influence of noise and miniaturizing the size of the sensor itself.

[0015] Another technical objective of the present invention is to provide a method for manufacturing a current sensor that includes a core capable of minimizing the size of the sensor itself while maintaining high sensitivity during commercial frequency current measurement and miniaturizing the effect of noise.

[0016] Another technical objective of the present invention is to provide a current sensor having a compact structure that can be mounted without penetrating power lines, while maintaining high sensitivity in the commercial frequency band and minimizing the influence of external noise.

[0017] The problems solved by the present invention are not limited to those mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the description below.

[0018] According to at least one embodiment of the present invention, a current sensor is provided comprising: a substrate including an insulating layer and a conductor layer formed on both sides of the insulating layer; a plurality of via holes formed to penetrate the insulating layer and the conductor layer, with a conductive film formed on the inner wall; at least one coil formed by a line patterning formed to connect the plurality of via holes to the conductor layer; and a core disposed inside the coil along the central axis of the coil.

[0019] According to at least one embodiment of the present invention, a current sensor is provided comprising at least one coil formed with the first direction as the central axis by winding an insulating coated wire in a spiral shape through two rows of through grooves formed parallel in a first direction on a substrate of an insulating material, and a core disposed inside the coil along the central axis of the coil.

[0020] In at least one embodiment of the present invention, the current sensor further comprises a circuit portion for outputting to the outside a signal indicating the magnitude of the current flowing in the power line measured by the coil, which is positioned close to the coil, and a connection portion for electrically connecting the coil and the circuit portion, wherein the circuit portion is positioned close to the coil such that the line constituting the connection portion has the shortest length.

[0021] In at least one embodiment of the present invention, the current sensor further comprises a circuit portion for outputting to the outside a signal indicating the magnitude of the current flowing in the power line measured by the coil, and a connection portion for electrically connecting the coil and the circuit portion, wherein the circuit portion is positioned close to the coil such that the length of the component of the line parallel to the power line among the lines constituting the connection portion is minimized.

[0022] In at least one embodiment of the present invention, the current sensor further comprises a circuit portion for outputting to the outside a signal indicating the magnitude of the current flowing in the power line measured by the coil, which is positioned in close proximity to the coil, and a connection portion for electrically connecting the coil and the circuit portion, and the signal output terminal of the coil is formed at a position where the length of the component of the line parallel to the power line is minimized among the line from the end of the coil to the signal output terminal.

[0023] In at least one embodiment of the present invention, the coil comprises a plurality of coils connected in series or in parallel with one another, and the plurality of coils are arranged such that the length of the component of the line connecting the plurality of coils in series or in parallel that is parallel to the power line is minimized.

[0024] In at least one embodiment of the present invention, the current sensor further comprises a circuit portion disposed in close proximity to the coil for outputting to the outside a signal indicating the magnitude of the current flowing in the power line measured by the coil, and a connection portion for electrically connecting the coil and the circuit portion, wherein the sensor portion and the coil are formed on the same substrate.

[0025] In at least one embodiment of the present invention, the current sensor further comprises a circuit portion for outputting to the outside a signal indicating the magnitude of the current flowing in a power line measured by the coil, which is positioned in close proximity to the coil, and a connection portion for electrically connecting the coil and the circuit portion, wherein the sensor portion and the circuit portion are formed on a first substrate and a second substrate, respectively, and the first substrate and the second substrate are positioned to overlap each other in a normal direction.

[0026] In at least one embodiment of the present invention, the current sensor further comprises a circuit portion disposed in close proximity to the coil for outputting to the outside a signal indicating the magnitude of the current flowing in the power line measured by the coil, and a connection portion for electrically connecting the coil and the circuit portion, wherein the circuit portion includes at least a low-pass filter and an amplifier.

[0027] In at least one embodiment of the present invention, the current sensor further comprises a circuit portion disposed in close proximity to the coil for outputting to the outside a signal indicating the magnitude of the current flowing in the power line measured by the coil, a connection portion for electrically connecting the coil and the circuit portion, and a shielding case made of a conductive material configured in a box shape having an opening on a first side for housing both the coil and the circuit portion inside.

[0028] According to at least one embodiment of the present invention, a method for manufacturing a current sensor comprises: a substrate including an insulating layer and a conductor layer formed on both sides of the insulating layer; a plurality of via holes formed to penetrate the insulating layer and the conductor layer and having a conductive film formed on the inner wall; and at least one coil formed to connect the plurality of via holes to the conductor layer and a line pattern formed to connect the plurality of via holes, and a core disposed inside along the central axis of the coil, the method comprising: a first step of manufacturing a first substrate including the core by inserting a core member between two insulating layers and then compressing the two insulating layers; a second step of forming the via holes on both sides of the core on the first substrate manufactured in the first step; a third step of manufacturing a second substrate by forming the conductor layer and the conductive film on the first substrate having the via holes formed thereon; and a fourth step of forming the coil including the core through a line pattern to connect the plurality of via holes on the second substrate manufactured in the third step.

[0029] According to at least one embodiment of the present invention, a method for manufacturing a current sensor comprising at least one coil formed with the first direction as a central axis and a core disposed inside along the central axis of the coil by winding an insulating coated wire in a spiral shape through two rows of through grooves formed parallel to each other in a first direction on an insulating substrate, the method comprising: a first step of manufacturing a first substrate including the core by inserting a core member between two substrates and then compressing the two substrates; a second step of forming the through grooves on both sides of the core on the first substrate manufactured in the first step; and a third step of forming the coil by winding the insulating coated wire in a spiral shape on the first substrate having the through grooves formed thereon.

[0030] According to at least one embodiment of the present invention, a method for manufacturing a current sensor comprising a substrate including an insulating layer and a conductor layer formed on both sides of the insulating layer, a plurality of via holes formed to penetrate the insulating layer and the conductor layer and having a conductive film formed on the inner wall, and a line pattern formed to connect the plurality of via holes to the conductor layer, and a core disposed inside along the central axis of the coil, is provided, the method comprising: a first step of forming the coil on the substrate; a second step of forming a through hole inside the coil along the central axis of the coil formed in the first step; and a third step of forming the core by inserting a core member into the through hole formed in the second step.

[0031] According to at least one embodiment of the present invention, a method for manufacturing a current sensor comprising at least one coil formed with the first direction as a central axis and a core disposed inside along the central axis of the coil by winding an insulating coated wire in a spiral shape through two rows of through grooves formed parallel to each other in a first direction on a substrate of an insulating material, the method comprising: a first step of forming the coil on the substrate; a second step of forming a through hole inside the coil along the central axis of the coil formed in the first step; and a third step of forming the core by inserting a core member into the through hole formed in the second step.

[0032] Although each embodiment in this specification is described independently, each embodiment may be combined with one another, and combined embodiments are also included within the scope of the present invention.

[0033] The summary for the foregoing is for illustrative purposes only and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by referring to the drawings and the detailed description below.

[0034] According to at least one embodiment of the present invention, there is an effect of providing a current sensor including a core that can maintain high sensitivity during commercial frequency current measurement while minimizing the influence of noise and miniaturizing the size of the sensor itself.

[0035] In addition, according to at least one embodiment of the present invention, there is an effect of providing a method for manufacturing a current sensor including a core that can maintain high sensitivity when measuring current at commercial frequency, minimize the influence of noise, and miniaturize the size of the sensor itself.

[0036] In addition, according to at least one embodiment of the present invention, there is an effect of providing a current sensor having a compact structure that can be mounted without penetrating power lines while minimizing the influence of external noise while maintaining high sensitivity in the commercial frequency band.

[0037] The effects of the present invention are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art from the description below.

[0038] FIG. 1 is a conceptual diagram of a current sensor including a core according to at least one embodiment of the present invention.

[0039] Figure 2 is a side cross-sectional view of a current sensor including the core shown in Figure 1.

[0040] FIGS. 3 and FIGS. 4 are process diagrams for explaining a method for manufacturing a current sensor including a core according to at least one embodiment of the present invention.

[0041] FIG. 5 is a conceptual diagram of a current sensor including a core according to at least one embodiment of the present invention.

[0042] FIGS. 6 to 8 are conceptual diagrams showing a state in which a current sensor according to at least one embodiment of the present invention is mounted on a power line.

[0043] FIG. 9 is an exploded perspective view showing the assembly process of a current sensor according to at least one embodiment of the present invention.

[0044] FIG. 10 is a side cross-sectional view showing a current sensor according to at least one embodiment of the present invention mounted on a power line.

[0045] FIG. 11 is a side view showing a form in which a current sensor according to at least one embodiment of the present invention is mounted on a power line.

[0046] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings.

[0047] FIG. 1 is a conceptual diagram of a current sensor including a core according to at least one embodiment of the present invention. FIG. 2 is a side cross-sectional view of a current sensor including a core shown in FIG. 1.

[0048] As illustrated in FIG. 1, a current sensor including a core according to at least one embodiment of the present invention comprises a substrate (110) including an insulating layer and a conductor layer formed on both sides of the insulating layer, a plurality of via holes (111) formed to penetrate the insulating layer and the conductor layer and having a conductive film formed on the inner wall, and a line patterning (113) formed to connect the plurality of via holes (111) to the conductor layer, and a core (114) inserted inside along the central axis of the coil.

[0049] As illustrated in FIG. 1, a conductive film (112) is formed inside a plurality of via holes (111) formed in a zigzag shape or in a straight line in two parallel rows in the y direction (first direction) on a substrate (110), and a line patterning (113) is formed to electrically connect the via holes (111) on both sides in a spiral shape. As illustrated below the arrow in FIG. 1, a coil (C1) having a length L and a major axis length a is formed through a spiral structure between a starting point (S) and an end point (E). At this time, the minor axis length b of the coil (C1) corresponds to the thickness of the first substrate (310).

[0050] Here, the first direction refers to a direction that intersects the length direction of the power line when a current sensor is mounted on the power line to be measured. That is, a current sensor including a core according to at least one embodiment of the present invention is arranged such that the first surface faces the surface of the power line in a direction in which the central axis of the coil (C1) intersects the power line.

[0051] In at least one embodiment of the present invention, the coil (C1) includes a core (114) in the center. While a coreless coil has the advantage of not becoming saturated, a coil having a core (e.g., an iron core) has the disadvantage of becoming saturated when the magnetic flux density of the iron core reaches its maximum, but has the advantage of increasing sensitivity.

[0052] While a large number of coil turns are required to obtain high inductance using only a coil, using a conductor with high relative permeability as a core can improve coil characteristics. Since the influence of other conductors near the coil is minimal when using a core, dense component mounting is also possible.

[0053] In the case of iron core coils, the material mainly used is a steel plate containing silicon components, which can be used at low frequencies from direct current to tens of kHz.

[0054] Magnetic core coils are divided into dust cores, which are simply compression-molded metal powder, and ferrite cores, which are compression-molded sintered metal oxide powder; dust cores can be mainly used in high-power RF circuits, while ferrite cores can be mainly used in broadband circuits.

[0055] In at least one embodiment of the present invention, the substrate (110) includes a printed circuit board (PCB) in which an insulating layer and a conductive layer are laminated in the form of a substrate, and a desired circuit can be formed through the patterning of the conductive layer.

[0056] In at least one embodiment of the present invention, a plurality of via holes are formed in two parallel rows in a first direction (y direction), as shown in FIG. 1.

[0057] FIGS. 3 and FIGS. 4 are process diagrams for explaining a method for manufacturing a current sensor including a core according to at least one embodiment of the present invention.

[0058] FIG. 3 shows a method of forming a core by inserting a core member between two insulating layers and then compressing the two insulating layers when forming an insulating layer of a substrate, and FIG. 4 shows a method of forming a core by manufacturing a sensor part, then drilling a hole in the inside of the coil from the side and inserting a core member into the hole.

[0059] As illustrated in FIG. 3, a method for manufacturing a current sensor according to at least one embodiment of the present invention forms an insulating layer (110-3) including a core (114) by placing a core (114) between a first insulating layer (110-1) and a second insulating layer (110-2) and compressing the first insulating layer (110-1) and the second insulating layer (110-2) (Fig. 3 (a)) (Fig. 3 (b)).

[0060] Afterwards, a plurality of via holes (111) are formed on both sides of the core (114) (Fig. 3 (c)), and a conductor layer (110-4) and a conductive film (112) are formed on both sides of the insulating layer (110-3) using processes such as metal plating and copper foil bonding (Fig. 3 (d)).

[0061] As shown in FIG. 3 (d), a core (114) is inserted inside, and a conductor layer (110-4) and a conductive film (112) are formed on a substrate (110) through pattern design and etching to form a line patterning (113) and a line (115) to form a coil containing a core (114) inside (Fig. 3 (e)).

[0062] A method for manufacturing a current sensor according to at least one embodiment of the present invention illustrated in FIG. 4 involves forming a plurality of via holes (111) in a substrate (110) comprising an insulating layer and a conductive layer formed on both sides of the insulating layer (Fig. 4 (a) and FIG. 4 (b)), and forming a conductive film (112) using a process such as metal plating (Fig. 4 (c)).

[0063] Afterwards, a line patterning (113) and a line (115) are formed through pattern design and etching to form a coil without a core (114) inside (Fig. 4 (d)).

[0064] After configuring a coil without a core (114) inside as in FIG. 4 (d), a through hole (116) is formed inside the coil through drilling (Fig. 4 (e)), and when a coil member is inserted into the through hole (116), a coil containing a core (114) inside is completed as in FIG. 4 (f).

[0065] In the example illustrated in FIG. 4, the step of forming a plurality of via holes (111) in a substrate (110) including an insulating layer and a conductive layer formed on both sides of the insulating layer is described, but a plurality of via holes (111) may be formed in the insulating layer first, and then a conductive layer and a conductive film (112) may be formed using processes such as metal plating and copper foil bonding.

[0066] In other words, the example illustrated in FIG. 3 describes a method of forming a coil after manufacturing a substrate into which a core member is inserted, and the example illustrated in FIG. 4 describes a method of inserting a core member by drilling a hole inside the coil after forming a coil on the substrate.

[0067] FIG. 5 is a conceptual diagram of a current sensor including a core according to at least one embodiment of the present invention.

[0068] The coil (C1) of the current sensor illustrated in Fig. 5 is formed by winding an insulating coated wire (513) in a spiral shape through two rows of through grooves (512) formed parallel in the y direction (first direction) on an insulating substrate (510), with the first direction as the central axis.

[0069] A current sensor according to at least one embodiment of the present invention may have a structure similar to the current sensor shown in FIG. 1, except that the coil used in the sensor part is formed as an actual insulated coil.

[0070] In at least one embodiment of the present invention, the sensor unit comprises a coil (C1) that functions as an induction coil and may include a core (e.g., an iron core) inside. While a coreless coil has the advantage of not becoming saturated, a coil having an iron core has the disadvantage of becoming saturated when the magnetic flux density of the iron core reaches its maximum, but has the advantage of increased sensitivity.

[0071] The core can be formed, for example, by inserting a core member between two insulating layers and then compressing the two insulating layers when forming the insulating layer of the substrate, or by making a hole in the inside of the coil from the side and inserting the core member into the hole after manufacturing the sensor part.

[0072] In the current sensor illustrated in FIG. 5, when creating the line pattern for coil formation, the length of the line (515) parallel to the power line is formed as short as possible (or minimized).

[0073] Generally, for low-frequency power with a commercial frequency of 50 Hz or 60 Hz, unlike high-frequency power in the RF band, it is difficult to measure the current flowing through the power line because the level of the induced current caused by the magnetic flux generated in the power line does not differ significantly from the ambient (atmosphere) noise level.

[0074] In order to solve such problems, the present invention, in at least one embodiment, raises the signal detection efficiency of the sensor unit to a commercialization stage through the following structure.

[0075] i) When creating a line pattern for forming a coil in the sensor section, the length of the line parallel to the power line (e.g., line (115) of FIG. 1) is formed as short as possible (or minimized).

[0076] ii) The distance between the sensor part and the circuit part is made as short as possible (or minimized).

[0077] iii) When the sensor section and the circuit section are formed on separate substrates, in order to minimize the influence of lines other than the coils when forming multiple coils, the output terminal of the sensor section is positioned at the center of the multiple coils, or the output terminal is positioned at each side edge of the substrate. In the latter case, the shortest distance between the sensor section and the circuit section can be secured from the circuit section side.

[0078] iv) When the sensor part and the circuit part are formed on separate substrates, the sensor part and the circuit part are arranged so as to be close to each other in one direction orthogonal to the power line.

[0079] v) A shielding case in the shape of a metal box is provided to minimize the influence of external noise.

[0080] vi) Both the sensor unit and the circuit unit are housed inside a shielded case.

[0081] vii) The circuit includes at least a low-pass filter and an amplifier.

[0082] In this specification, placing the circuit portion close to the coil is intended to reduce the inflow of external noise by shortening the length of the connection portion, and in particular to suppress inductive noise by minimizing the length of the conductor extending in a direction parallel to the power line.

[0083] In this specification, "minimizing the length of the component parallel to the power line" means reducing the total length of the conductor path arranged in substantially the same direction as the extension direction of the power line, thereby suppressing the coupling of unwanted noise components induced from the power line.

[0084] FIG. 6 is a conceptual diagram showing a state in which a current sensor (600) according to at least one embodiment of the present invention is mounted on a power line (e.g., a busbar) (P). FIG. 7 is a conceptual diagram showing a state in which a current sensor (700) according to at least one embodiment of the present invention is mounted on a power line (P). FIG. 8 is a conceptual diagram showing a state in which a current sensor (800) according to at least one embodiment of the present invention is mounted on a power line (P).

[0085] In FIGS. 6 and FIGS. 8, (a) is a perspective view close to a top view of a current sensor mounted on a power line (P), and (b) is a side view of a current sensor mounted on a power line (P).

[0086] The current sensor (600) illustrated in FIG. 6 comprises a substrate (610) including a conductor layer formed on both sides of an insulating layer with an insulating layer in between, a sensor part (620) formed on the substrate (610), a circuit part (630) formed on the same substrate (610) as the sensor part (620) to receive an output from the sensor part (620) and output a current signal indicating the strength of the current flowing in the power line through a predetermined signal processing, and a connection part (640) for electrically connecting the sensor part (620) and the circuit part (630).

[0087] When current flows through the power line (P), a magnetic field is formed around the power line (P), and the sensor unit (620) detects the magnetic flux flowing along the magnetic field and outputs a signal indicating the strength of the current flowing through the power line (P).

[0088] At this time, the sensor unit (620) detects the magnetic flux caused by the low-frequency current flowing through the power line (P). Since the level of the detected signal does not differ significantly from the noise level around the power line (P) (in the atmosphere), it is necessary to form a line parallel to the power line (P) as short as possible inside the current sensor (600) in order to minimize the influence on the signal level of the sensor unit (620).

[0089] This is so that, as described in Patent Document 1, a line parallel to the power line (P) can be a different current detection source from the sensor unit (620), and thus not affect the signal level of the sensor unit (620).

[0090] In addition, by minimizing the length of the output line of the sensor unit (620) and the connection unit (640) that electrically connects the sensor unit (620) and the circuit unit (630) (minimizing the distance between the sensor unit (620) and the circuit unit (630)), the signal detection efficiency of the sensor unit (620) can be improved.

[0091] As mentioned above, in the case of low-frequency power in the commercial frequency band of 50 Hz or 60 Hz, unlike high-frequency power in the RF band, the level of induced current caused by magnetic flux generated in the power line does not differ significantly from the ambient (atmosphere) noise level. Furthermore, when fabricating the line pattern for coil formation in the sensor section, the current signal detected by the line parallel to the power line among the lines from the connection between the sensor section and the circuit section to the inside of the circuit section provides another noise source different from the ambient noise.

[0092] Accordingly, to solve the above problems, in at least one embodiment of the present invention, a plurality of coils are connected in series or in parallel to increase the signal level of the sensor unit, and when fabricating a line pattern for coil formation in the sensor unit, the length of the line parallel to the power line among the line parallel to the power line, the line from the connection between the sensor unit and the circuit unit to the inside of the circuit unit, and the line connecting the circuit unit and the external device connection unit is minimized, and the distance between the sensor unit and the circuit unit is formed to be as short as possible so that the current signal can be efficiently transmitted from the sensor unit to the circuit unit.

[0093] In at least one embodiment of the present invention, a substrate comprising at least one coil formed by a plurality of via holes and line patterning is configured such that a first surface is mounted close to a power line (P) in a direction in which the central axis of the coil intersects a power line for measuring current.

[0094] That is, a current sensor according to at least one embodiment of the present invention can measure the current flowing in a power line by mounting it on a power line in such a way that the first surface of the sensor part is close to the power line without bypassing or cutting the power line for measuring the current.

[0095] In at least one embodiment of the present invention, the sensor unit includes a plurality of coils formed with central axes parallel to each other, and the plurality of coils are connected in parallel or in series.

[0096] Since the sensor unit detects the amount of current flowing in the power line (P) by the induced current induced in the coil, the greater the amount of induced current, the higher the sensitivity can be. Therefore, sensitivity can be improved by increasing the amount of induced current by connecting multiple coils formed with their central axes parallel to each other in parallel, or by increasing the induced electromotive force by connecting them in series.

[0097] The current sensor (700) illustrated in FIG. 7 comprises a substrate (710) including a conductor layer formed on both sides of an insulating layer with an insulating layer in between, a sensor part (720) formed on the substrate (710), a circuit part (730) formed on the same substrate (710) as the sensor part (720) to receive an output from the sensor part (720) and output a current signal indicating the strength of the current flowing in the power line through a predetermined signal processing, and a connection part (740) for electrically connecting the sensor part (720) and the circuit part (730).

[0098] While the current sensor (600) illustrated in FIG. 6 is configured to consist of a sensor section (620), a circuit section (630) formed along a power line (P), and a connection section (640) for electrically connecting the sensor section (620) and the circuit section (630) in the direction of the power line (P), the current sensor (700) illustrated in FIG. 7 is configured such that the sensor section (720) and the circuit section (730) are formed on the same substrate (710), but the sensor section (720) and the circuit section (730) are arranged in a direction orthogonal to the power line (P), and the connection section (740) is configured to electrically connect the sensor section (720) and the circuit section (730) in a direction orthogonal to the power line (P).

[0099] The current sensor (700) illustrated in Fig. 7 has the disadvantage that the current sensor itself is separated from the power line (P) and requires more space on the side of the power line (P), but it has the advantage of being able to further improve the signal detection efficiency of the sensor unit (720) by eliminating a line parallel to the power line (P) compared to the current sensor (600) illustrated in Fig. 6.

[0100] The current sensor (800) illustrated in FIG. 8 comprises a first substrate (810) including a conductive layer formed on both sides of an insulating layer with an insulating layer in between, a sensor part (811) formed on the first substrate (810), a second substrate (820) including a conductive layer formed on both sides of an insulating layer with an insulating layer in between, a circuit part (821) formed on the second substrate (820) for receiving an output from the sensor part (811) and outputting a current signal indicating the strength of the current flowing in the power line through a predetermined signal processing, and a connection part (840) for electrically connecting the sensor part (811) and the circuit part (821).

[0101] While the current sensor (600) illustrated in FIG. 6 and the current sensor (700) illustrated in FIG. 7 have a structure in which the sensor part and the circuit part are formed on the same substrate, the current sensor (800) illustrated in FIG. 8 has a structure in which the sensor part (811) and the circuit part (821) are formed on separate, independent substrates and are electrically connected by a connecting part (840) as if stacked in one direction orthogonal to the power line (P). At this time, the connecting part (840) can perform the function of electrically connecting the sensor part (811) and the circuit part (821) while simultaneously physically fixing them.

[0102] In this way, by forming the sensor section (811) and the circuit section (821) on separate, independent substrates and electrically connecting them via the connection section (840) in a stacked manner orthogonal to the power line (P), the distance between the sensor section (811) and the circuit section (821) can be minimized while excluding the line parallel to the power line (P), thereby having the advantage of further improving the signal detection efficiency of the sensor section (811).

[0103] At this time, the connecting part (840) needs to be formed as short as possible (minimizing length) while electrically connecting the sensor part (811) and the circuit part (821) and fixing them so that they do not come into physical contact.

[0104] As shown in FIGS. 6 to 8, current sensors (600, 700, 800) are configured to be mounted on a power line (e.g., a busbar) (P) to measure an induced current caused by a change in magnetic flux that occurs when current flows through the power line (P).

[0105] To this end, the sensor portion (620, 720, 811) is configured to include at least one coil formed to penetrate the insulating layer and the conductor layer of the substrate (610, 710, 810), with a plurality of via holes having a conductive film formed on the inner wall and a line pattern formed to connect the plurality of via holes to the conductor layer.

[0106] In at least one embodiment of the present invention, the sensor unit comprises a plurality of coils, and the plurality of coils are connected in series or in parallel to each other and configured to maximize the amount of induced electromotive force or induced current caused by the magnetic flux generated by the current flowing through the power line (P) to a substrate of a given size.

[0107] FIG. 9 is an exploded perspective view showing the assembly process of a current sensor according to at least one embodiment of the present invention.

[0108] A current sensor according to at least one embodiment of the present invention further comprises a shielding case (930) made of a conductive (metal) material configured in a box shape having an opening on a first side, as shown in FIG. 9.

[0109] A shielding case (930) according to at least one embodiment of the present invention is configured in the form of a box made of a conductive material to block external noise entering from all directions, for shielding noise from the outside when detecting magnetic flux of a power line transmitting low-frequency (e.g., commercial frequency) power.

[0110] The shielding case (930) is configured such that both sides of the first direction of the first substrate (810) are inserted into the opening to block the opening.

[0111] Accordingly, when the shielding case (930) is mounted on the power line (P) such that the L2 surface of the first substrate (810) is close to the power line (P), the shielding case (930) shields the opposite side of the power line (P), and the power line (P) itself acts to shield the side of the power line (P).

[0112] With this structure, the magnetic flux generated when current flows through the power line (P) enters the coils (C1~Cn) of the sensor unit while shielding all sides of the sensor unit, so the width of the sensor unit (length in the first direction) needs to be set to be less than or equal to the width of the power line (P).

[0113] In at least one embodiment of the present invention, the sensor unit is positioned inside the shielding case (930) in a direction in which the magnetic flux generated from the power line (P) is best transmitted, so that magnetic changes generated from the power line (P) are efficiently detected.

[0114] In FIG. 1, a plurality of via holes (111) are shown formed in two parallel rows in a zigzag shape in the first direction, but this is an arrangement for connecting a plurality of via holes (111) in a spiral coil shape through line patterning (113), and as long as a plurality of via holes (111) can be connected in a spiral coil shape through line patterning (113), they may be formed in two straight rows instead of a zigzag shape.

[0115] When multiple via holes (111) are formed in two parallel lines in a straight line in the first direction, the number of via holes on one side may be one more or one less as needed, and in either case, the line patterning (113) must connect multiple via holes (111) diagonally on at least one side, so the expression zigzag is used, but as long as they are formed in two parallel lines, the zigzag and the straight line can be seen as the same form.

[0116] In at least one embodiment of the present invention, the line patterning (113) is formed on the conductor layers on both sides of the insulating layer so as to form a coil (C1~Cn) with the first direction as the central axis by electrically connecting a plurality of via holes (111) formed in two parallel rows in a zigzag shape as described above.

[0117] In at least one embodiment of the present invention, a substrate (110) comprising at least one coil (C1~Cn) formed by a plurality of via holes (111) and line patterning (113) is configured such that a first surface is mounted close to a power line (P) in a direction in which the central axis of the coil (C1~Cn) intersects the power line for measuring current.

[0118] That is, a current sensor according to at least one embodiment of the present invention can measure the current flowing in a power line by mounting it on a power line in such a way that the first surface of the sensor part is close to the power line without bypassing or cutting the power line for measuring the current.

[0119] In at least one embodiment of the present invention, the sensor unit includes a plurality of coils (C1 to Cn) formed with central axes parallel to each other, and the plurality of coils (C1 to Cn) are connected in parallel or in series.

[0120] Since the sensor unit detects the amount of current flowing in the power line (P) by the induced current induced in the coils (C1~Cn), the sensitivity can be improved as the amount of induced current increases. Therefore, sensitivity can be improved by increasing the amount of induced current by connecting multiple coils (C1~Cn) formed with their central axes parallel to each other in parallel, or by increasing the induced electromotive force by connecting them in series.

[0121] In at least one embodiment of the present invention, the current sensor comprises a sensor unit including coils (C1~Cn) for detecting current flowing in a power line, and a circuit unit connected to the output terminal of the sensor unit, including a filter unit for noise removal and an amplifier unit for amplifying the signal passed through the filter unit.

[0122] The coils (C1~Cn) of the current sensor are a sensing unit that outputs a sinusoidal induced current by mounting them close to a power line through which current flows, thereby allowing a rotating magnetic field generated from the power line to enter the coil.

[0123] The filter section passes the induced current through a low-pass filter, allowing low-frequency signals to pass through based on a certain frequency while removing high-frequency signals. The signal passing through the amplifier section then passes through a high-pass filter, which removes DC noise and signals below a certain frequency.

[0124] The amplifier section uses a differential amplifier to amplify the input signal by approximately 1,000 times after passing through a low-pass filter, and outputs a sine wave. The amplification rate can be set as needed.

[0125] In at least one embodiment of the present invention, a signal output terminal (822) for outputting a signal from a circuit to the outside and a power supply terminal (823) for supplying power to a circuit are electrically connected to the first substrate (810) or the second substrate (820).

[0126] In at least one embodiment of the present invention, the shielding case (930) includes a power supply port (not shown) for passing a power line for supplying power to a circuit part and a signal output port (not shown) for passing a signal output line from the circuit part.

[0127] FIG. 10 is a side cross-sectional view showing a current sensor according to at least one embodiment of the present invention mounted on a power line (P). In the example shown in FIG. 11, only a substrate including a sensor part is shown for convenience of explanation.

[0128] As illustrated in FIG. 10, a substrate (110) with a sensor portion formed thereon is mounted in a shielding case (1020) in a manner that covers an opening, and then the shielding case (1020) is inserted into a mounting member (1010) so that the substrate (110) faces inward, and the substrate (110) is mounted on a power line (P) so that it is close to the power line (P). When current flows through the power line (P), the magnetic flux (M) generated passes through the coil (C) of the sensor portion formed on the substrate (110) and is converted into an induced current. That is, the coil (C) of the sensor portion functions as an induction coil that induces the magnetic flux (M) generated when current flows through the power line (P).

[0129] When alternating current flows through a power line (P), the magnetic flux (M) generated around the power line (P) flows into the coil (C), and the resulting change in magnetic flux inside the coil (C) is converted into an induced current or induced electromotive force through the coil (C) and output. Therefore, the amount of current flowing through the power line (P) can be calculated by calculating such an induced current or induced electromotive force.

[0130] That is, a current sensor according to at least one embodiment of the present invention has a structure in which a substrate (110) is mounted on a shielding case (1020), and when the substrate is inserted into a mounting member (1010) and mounted on a power line (P), the shielding case (1020) and the power line (P) shield all directions of the sensor part with the bottom surface of the mounting member (1010) in between.

[0131] With the above structure, the magnetic flux generated when current flows through the power line (P) enters the coil (C) and shields all sides of the sensor part, so the width of the sensor part (length in the first direction) needs to be set to be less than or equal to the width of the power line (P).

[0132] According to the configuration of the present invention as described above, electromagnetic noise transmitted from outside the power line (P) is blocked by the shielding case (1020), and magnetic changes generated in the power line (P) are mainly detected by the magnetic flux (M) being transmitted to the sensor unit inside the shielding case (1020), thereby minimizing the influence of external noise.

[0133] FIG. 11 is a side view showing a configuration in which a current sensor according to at least one embodiment of the present invention is mounted on a power line (P).

[0134] FIG. 11 (a) shows a configuration in which the first substrate (810) and the second substrate (820) are electrically connected by a connecting part (840), so that the first substrate (810) is positioned closer to the power line (P) than the second substrate (820) and parallel to the power line (P).

[0135] Figure 11(b) shows a configuration in which a power line (P) passes through a hole formed in a controller board (1110) on which an MCU (1111) is mounted, and a sensor part (620), a circuit part (630), and a connection part (640) for electrically connecting the sensor part (620) and the circuit part (630) are formed on the controller board (1110).

[0136] That is, in FIG. 11 (b), instead of the substrate (610) shown in FIG. 6, a form is shown in which a current sensor is configured using a controller substrate (1110) on which an MCU (1111) is mounted to detect the current flowing in the power line (P) and perform power management.

[0137] As described above, according to at least one embodiment of the present invention, a current sensor including a core that can maintain high sensitivity while minimizing the influence of noise and miniaturizing the size of the sensor itself when measuring current at commercial frequency can be provided.

[0138] In addition, according to at least one embodiment of the present invention, a current sensor having a compact structure that can be mounted without penetrating power lines while minimizing the influence of external noise while maintaining high sensitivity in the commercial frequency band can be provided.

[0139] In addition, according to at least one embodiment of the present invention, a method for manufacturing a current sensor including a core that can maintain high sensitivity when measuring current at commercial frequency while minimizing the influence of noise and miniaturizing the size of the sensor itself can be provided.

[0140] Although the present invention has been described above using several embodiments, these embodiments are illustrative and not limiting. As such, those skilled in the art will understand that various changes and modifications can be made in accordance with the doctrine of equivalents without departing from the spirit of the invention and the scope of rights set forth in the appended claims.

[0141] The present invention can be applied to fields such as maximizing power usage efficiency through the prediction and analysis of power demand, and protecting power systems through the detection of fault currents and rapid isolation of faulted systems.

Claims

1. At least one coil comprising a plurality of via holes formed to penetrate the insulating layer and the conductive layer of a substrate including an insulating layer and conductive layers formed on both sides of the insulating layer, wherein a conductive film is formed on the inner wall of the via hole, and a line pattern formed to connect the plurality of via holes to the conductive layer; and A core disposed inside the coil along the central axis of the coil. , equipped with Current sensor.

2. At least one coil formed with the first direction as the central axis by winding an insulating coated wire in a spiral shape through two rows of through grooves formed parallel in a first direction on a substrate of insulating material; and A core disposed inside the coil along the central axis of the coil. , equipped with Current sensor.

3. In Paragraph 1 or 2, A circuit portion disposed in close proximity to the coil and for outputting to the outside a signal indicating the magnitude of the current flowing in the power line measured by the coil; and A connecting part for electrically connecting the above coil and the above circuit part Equipped with more, The above circuit section is positioned close to the coil such that the line constituting the connection section has the shortest length. Current sensor.

4. In Paragraph 1 or 2, A circuit portion disposed in close proximity to the coil and for outputting to the outside a signal indicating the magnitude of the current flowing in the power line measured by the coil; and A connecting part for electrically connecting the above coil and the above circuit part Equipped with more, The above circuit section is positioned close to the coil such that the length of the component of the line parallel to the power line among the lines constituting the connection section is minimized. Current sensor.

5. In Paragraph 1 or 2, A circuit portion disposed in close proximity to the coil and for outputting to the outside a signal indicating the magnitude of the current flowing in the power line measured by the coil; and A connecting part for electrically connecting the above coil and the above circuit part Equipped with more, The signal output terminal of the above coil is formed at a position where the length of the component of the line parallel to the power line is minimized among the line from the end of the coil to the signal output terminal. Current sensor.

6. In Paragraph 1 or 2, The above coil includes a plurality of coils connected to each other in series or parallel, and The plurality of coils are arranged such that the length of the component parallel to the power line among the lines connecting the plurality of coils in series or parallel is minimized. Current sensor.

7. In Paragraph 1 or 2, A circuit portion disposed in close proximity to the coil and for outputting to the outside a signal indicating the magnitude of the current flowing in the power line measured by the coil; and A connecting part for electrically connecting the above coil and the above circuit part Equipped with more, The sensor part and the coil are formed on the same substrate, Current sensor.

8. In Paragraph 1 or 2, A circuit portion disposed in close proximity to the coil and for outputting to the outside a signal indicating the magnitude of the current flowing in the power line measured by the coil; and A connecting part for electrically connecting the above coil and the above circuit part Equipped with more, The sensor part and the circuit part are formed on the first substrate and the second substrate, respectively, and The first substrate and the second substrate are arranged to overlap each other in a normal direction, Current sensor.

9. In Paragraph 1 or 2, A circuit portion disposed in close proximity to the coil and for outputting to the outside a signal indicating the magnitude of the current flowing in the power line measured by the coil; and A connecting part for electrically connecting the above coil and the above circuit part Equipped with more, The above circuit section includes at least a low-pass filter and an amplifier, Current sensor.

10. In Paragraph 1 or 2, A circuit portion positioned in close proximity to the coil, for outputting to the outside a signal indicating the magnitude of the current flowing in the power line measured by the coil; A connecting part for electrically connecting the above coil and the above circuit part; and A shielding case made of a conductive material configured in a box shape having an opening on a first side to accommodate both the coil and the circuit part inside. further equipped with, Current sensor.

11. A method for manufacturing a current sensor comprising: at least one coil comprising a plurality of via holes formed to penetrate the insulating layer and the conductive layer and having a conductive film formed on the inner wall thereof, and a line pattern formed to connect the plurality of via holes to the conductive layer, and a core disposed inside along the central axis of the coil, wherein the coil comprises an insulating layer and a conductive layer formed on both sides of the insulating layer. A first step of manufacturing a first substrate including a core by inserting a core member between two insulating layers and then compressing the two insulating layers; A second step of forming via holes on both sides of the core for the first substrate manufactured in the first step; A third step of manufacturing a second substrate by forming the conductor layer and the conductive film on the first substrate having the via hole formed therein; and A fourth step of forming the coil including the core through line patterning to connect the plurality of via holes to the second substrate manufactured in the third step. including, Method for manufacturing a current sensor.

12. A method for manufacturing a current sensor comprising at least one coil formed with the first direction as the central axis by winding an insulating coated wire in a spiral shape through two rows of through grooves formed parallel to each other in a first direction on a substrate of insulating material, and a core disposed inside along the central axis of the coil, A first step of manufacturing a first substrate including a core by inserting a core member between two substrates and then compressing the two substrates; A second step of forming the through grooves on both sides of the core for the first substrate manufactured in the first step; and A third step of forming the coil by winding the insulating coating wire in a spiral shape with respect to the first substrate having the through groove formed therein. including, Method for manufacturing a current sensor.

13. A method for manufacturing a current sensor comprising: at least one coil comprising a plurality of via holes formed to penetrate the insulating layer and the conductive layer and having a conductive film formed on the inner wall thereof, and a line pattern formed to connect the plurality of via holes to the conductive layer, and a core disposed inside along the central axis of the coil, wherein the coil comprises an insulating layer and a conductive layer formed on both sides of the insulating layer. A first step of forming the coil on the substrate; A second step of forming a through hole inside the coil along the central axis of the coil formed in the first step; and A third step of forming the core by inserting a core member into the through hole formed in the second step above. including, Method for manufacturing a current sensor.

14. A method for manufacturing a current sensor comprising at least one coil formed with the first direction as the central axis by winding an insulating coated wire in a spiral shape through two rows of through grooves formed parallel in a first direction on a substrate of an insulating material, and a core disposed inside along the central axis of the coil, A first step of forming the coil on the substrate; A second step of forming a through hole inside the coil along the central axis of the coil formed in the first step; and A third step of forming the core by inserting a core member into the through hole formed in the second step above. including, Method for manufacturing a current sensor.

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