KR101776774B1 - Current sensing module having magnetic shielding structure - Google Patents

Abstract

The present invention relates to a current detecting module including a magnetic field shielding structure. According to an aspect to achieve the purpose of the present invention, the current detecting module including the magnetic field shielding structure includes: a first housing in a T-shaped insulation block with an open upper surface divided into a step type upper block having a different floor level and a linear lower block vertically fixed to the center of the lower surface of the upper block, wherein the upper block has an upper screw coupling unit cylindrically protruding and the first housing also has a protrusion protruding at a predetermined height; a shielding unit installed to enclose the outer side of the lower block except for the protrusion; a socket formed as a rectangular insulation block with an open upper surface and having a through hole, a slide slot, and a lower screw coupling unit; a booth bar inserted and coupled to the through hole; and a second housing having a sliding wing sliding and coupled to the slide slot. Therefore, the current detecting module blocks a magnetic field formed around a sensor due to the outer magnetic field and the booth bar adjacent to the sensor and prevents malfunction of the sensor by minimizing the influence duet to the magnetic field, thereby improving measurement sensitivity.

Description

TECHNICAL FIELD [0001] The present invention relates to a current sensing module having a magnetic field shielding structure,

The present invention relates to a current sensing module having a magnetic shielding structure for shielding magnetic field components formed around a sensor for sensing a current flowing in a bus bar.

Power refers to electric energy supplied to an electric device for a unit time or electric energy converted into another type of energy for a unit time. It is represented by P, which is the first letter of Power, and electric power (P) and voltage (V) (I) satisfies P = VI. The electrical energy supplied by the alternating current is expressed as the average power divided by the period, usually the power supplied during one period, since the current and the voltage continuously change. Such power, voltage, and current amount are measured for various purposes in an electric device as well as an electricity consumption measurement in a real life. Various power measurement devices are being developed and used as measurement devices.

Such a power measuring device is configured to penetrate a subject electric wire or a bus bar, and is equipped with a power or voltage measuring sensor or the like fixedly mounted on a mechanism through which a busbar or the like is penetrated. The measuring sensor includes a CT (Current Transformer) A coil, a Hall sensor or a Rogowskii coil is used (see Patent Application No. 10-2004-0051360, No. 10-2007-0095919).

In the power measuring apparatus, various studies have been made on the measuring sensor and the measuring method, but the specific internal structure of the measuring apparatus has not been researched and developed.

However, in order to measure single-phase or three-phase phase voltage, the currently used power measuring device is connected to a single device such as a wire or a bus bar to be measured, and a measuring module such as a measuring sensor and a bus bar are fixedly connected Therefore, it is necessary to separately manufacture the components in accordance with the rated or circuit type (single phase, three-phase three-wire type, three-phase four-wire type), and the module can not be replaced in the live state.

In addition, since the electric current measuring device using the hall sensor or the Rogowski coil measures the magnetic field formed by the electric current, it measures the influence of the current flowing in the adjacent electric wire or the bus bar or the external magnetic field, There was a problem with accuracy.

KR 10-2015-0100198 A KR 20-0464394 Y1

It is an object of the present invention to provide a magnetic field shielding structure for efficiently focusing a magnetic field formed around a sensor for detecting a current flowing through a bus bar and allowing a focused magnetic field to pass through a proper bypass path And to provide a current sensing module.

According to an aspect of the present invention, there is provided a current sensing module having a magnetic shielding structure, comprising: a stepped top block having one step and a bottomed bottom Shaped insulating block having an upper surface separated from the upper surface of the lower block, the upper block being recessed at both sides of the lower surface by a certain depth in the inward direction and having an upper screw projecting in a cylindrical shape on an inner surface positioned in a straight line with both sides of the lower surface, And a protrusion protruding at a predetermined height is formed on an outer surface of an upper end of the lower block; A shielding portion installed to surround the outside of the lower block excluding the protrusions, the outer surface of the shielding portion not forming a step with the protrusions; A through hole is formed at both lower ends in the longitudinal direction, and a slide slot is formed at a predetermined depth on the upper and lower surfaces of the front and rear surfaces in the direction perpendicular to the longitudinal direction, A socket having a lower screw engagement portion formed in a cylindrical shape and protruding from an outer surface at a position corresponding to a straight line with the screw engagement portion; A bus bar provided on both sides of the metal bar with a screw hole formed therein to be inserted into the through hole and fastened; And a second housing protruding outwardly from the front and rear sides of the sliding block so as to correspond to the slide slot, the sliding wing being slidably coupled to the slide slot, wherein a current flowing through the bus bar is sensed in an inner space of the lower block, Wherein the Hall sensor and the sensing unit are disposed so as to face the inner bottom surface of the lower block, wherein the Hall sensor and the sensing unit contact with the bus bar and detect the voltage information, respectively.

According to the present invention, the magnetic field formed around the sensor due to the bus bar and the external magnetic field adjacent to the sensor is blocked, thereby minimizing the influence thereof, thereby preventing malfunction of the sensor and improving the measurement sensitivity.

1 is an overall perspective view of a current sensing module having a magnetic shield structure according to an embodiment of the present invention,
Fig. 2 is an exploded perspective view of Fig. 1,
FIG. 3 is a view showing a substrate portion received in the first housing of FIG. 2,
4 is an enlarged perspective view of the shield of Fig.

The foregoing and other objects, features and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention and the manner of achieving them will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings. Like reference numerals refer to like elements throughout the specification.

FIG. 1 is an overall perspective view of a current sensing module having a magnetic shield structure according to an embodiment of the present invention, FIG. 2 is an exploded perspective view of FIG. 1, FIG. 3 is a perspective view of a substrate portion accommodated in the first housing of FIG. And Fig. 4 is an enlarged perspective view of the shielding portion of Fig.

Hereinafter, a current sensing module having a magnetic shield structure according to an embodiment of the present invention will be described with reference to the drawings.

1 and 2, a current sensing module having a magnetic shield structure according to an embodiment of the present invention includes a first housing 100, a shield 200, a socket 300, a bus bar 400 And a second housing 500.

The current sensing module according to the present invention is composed of a bi-directional assembly that is separated and assembled up and down to measure current and voltage of electricity flowing through the bus bar 400 by a sensor built in the first housing 100, It is preferable that the bus bar 400 is formed of a non-conductive material (e.g., synthetic resin) so as to serve also as a knob when installing the bus bar 400 on the circuit breaker.

First, the first housing 100 is divided into a T-shape having an open upper surface, which is divided into a stepped top block 110 having a step and a straight bottom block 120 fixed vertically to the bottom center of the top block, Insulating block.

Here, the upper block 110 may be formed with an upper screw coupling part 130, which is recessed at both sides of the lower end face by a certain depth inward and protrudes in a cylindrical shape on the inner side surface positioned in a straight line with both sides of the lower end face.

Here, the protrusion protrusion 140 protruding at a predetermined height may be formed on the outer surface of the upper end of the lower block 120.

At this time, in the inner space of the lower block 120, a hall sensor 151 for collecting the current flowing through the bus bar 400 in a non-contact manner and sensing current information, a sensing part 152 for detecting voltage information in contact with the bus bar And the hall sensor 151 and the sensing piece 152 are disposed to face the inner bottom surface of the lower block 120. In this case,

The substrate unit 150 includes a first substrate 150-1 having an upper surface on which the hall sensor 151 is formed to face an inner bottom surface of the lower block 120, A second substrate 150-2 disposed vertically opposite to the bottom of the bottom of the bottom block 120 so that the sensing piece 152 formed at one end in the longitudinal direction faces the inner bottom surface of the bottom block 120; And a third substrate 150-3 vertically disposed on the second substrate 150-2 so as to be symmetrical about the center of the upper surface.

The third substrate 150-3 is provided with a communication module C for communicating with the external network and current information of the bus bar 400 sensed by the hall sensor 151 and the sensing part 152, A control module A for calculating voltage information and a connection module B for mediating data transmission / reception between the communication module C and the control module A. [

The shield 200 is provided to surround the outer surface of the lower block 120 excluding the protrusion 140 so that the outer surface of the shield 200 is not stepped with the protrusion 140.

The shielding part 200 includes a tightening plate 210 formed to closely contact the outer bottom surface of the lower block 120 and a bent part 210 formed at upper and lower sides of the tightening plate 210, And a cover plate 230 extending from the bending part 220 and pressing the outer surface of the lower block 120.

At this time, it is preferable that the contact plate 210 and the cover plate 230 connected to each other by the bending pieces 220 are perpendicular to each other.

The shield 200 may be made of a ferromagnetic material such as Fe, Permalloy, Sillicon Steel, Fe-Co, or the like, which is a magnetic material having a high specific magnetic permeability and a saturation magnetization of at least 2000 Gauss. Si, Moly-Permalloy and Ferrite. For example, the soft magnetic alloy may be formed of permalloy widely used in a low frequency band of 1 kHz or lower.

In this regard, the characteristics of each material usable as the shield 200 of the present invention will be described as follows.

Electromagnetic shielding is a technique in which a specific portion of a space is surrounded by a conductor or a ferromagnetic material so that the inside is not influenced by an external magnetic field or conversely an electromagnetic field generated in the inside does not reach the outside. The intensity of the electromagnetic field which is reduced due to the electromagnetic field is called a shielding effect (SE).

This shielding effect SE is defined as the ratio of the received power P _t received through the specimen to the incident power P _i as shown in Equation 1 below or the electromagnetic wave shielding mechanism such as absorption, received with, or defined as the ratio of the electromagnetic waves (E _t) that is transmitted is transmitted to the electromagnetic wave (E ₁₎ that only incident, regardless of the internal multiple reflection), or the incident electric field (E _i) and magnetic field (H _i) field ( the sum of E _t) and magnetic field (H _t) can be defined, and the return loss for the electromagnetic wave shielding mechanism as shown in equation 2 below (R), the absorption loss (a) and the multi-reflection loss at a ratio of (M) .

In this case, the absorption loss A is calculated based on the following Equations 3 and 4, and the absorption loss A is inversely proportional to the skin depth? Of the material according to Equation 3, , The skin depth (delta) of the material is inversely proportional to the product of the conductivity () and the permeability () of the material.

Where f is the frequency, μ is the permeability of the material, σ is the conductivity, ε is the permittivity, t is the thickness of the material, and δ is the skin depth of the material.

Next, Table 1 below shows the conductivity () and the magnetic permeability ( _r ) of each of the various types of shielding materials.

Material type Conductivity (σ) [S / m] The permeability ( _r ) [H / m] Nickel 50 1.45 x 10 ⁷ Aluminum 3.5 × 10 ⁷ One Silicon iron (4% si) 1.67 × 10 ⁶ 7.0 x 10 ³ Pure iron 1.89 x 10 ⁷ 8.0 × 10 ³ Permalloy (45% Ni) 2.22 × 10 ⁶ 2.3 x 10 ⁴ Permalloy (48% Ni-Fe, Mu-metal) 2.08 × 10 ⁶ 3.415 × 10 ³ Permalloy (80% Ni-Fe, Mu-metal) 1.64 x 10 ⁶ 1.512 × 10 ⁴ Supermalloy (5% Mo, 79% Ni) 1.54 × 10 ⁶ 1.0 × 10 ⁶

When the order of increasing the product of the conductivity () and the permeability ( _r ) of each shielding material, that is, the absorption loss (A), is large in the order of Table 1, Supermalloy, Pure iron ), 45% nickel alloy permalloy (45% Ni), 80% nickel-iron alloy permalloy (80% Ni-Fe), electrical steel sheet, 48% nickel-iron alloy permalloy (48% Ni- Nickel, and Aluminum in that order.

Accordingly, the shield 200 according to the present invention is made of a material such as Supermalloy, Pure iron (which is a material having a large product of the conductivity? And the magnetic permeability? _R ) of the shielding material so as to increase the electromagnetic wave absorption loss (45% Ni, 80% Ni-Fe, 48% Ni-Fe) or an electric steel sheet as a shielding material.

A contact hole H1 is formed at a position corresponding to the bottom surface of the lower block 120 and the sensing piece 152 of the fastening plate 210 so that the sensing piece 152 contacts the bus bar 400 Thereby detecting voltage information.

Next, the socket 300 is provided with a rectangular insulating block having an opened upper surface. The socket 300 has through holes 310 at both lower ends in the longitudinal direction, (320) may be recessed by a predetermined depth.

Here, the socket 300 may have a lower screw coupling part 330 formed at a position corresponding to the straight line on the upper side screw coupling part 130 at both upper ends thereof so as to protrude from the outer surface in a cylindrical shape.

For example, as shown in FIG. 1, the shield 200 is closely attached to the upper surface of the lower block 120 of the first housing 100, and then the socket 300 and the second housing 500 are inserted The upper screw coupling part 130 and the lower screw coupling part 330 are placed on a straight line.

At this time, a fastening screw (not shown) may be further provided to penetrate and fasten both the upper screw coupling part 130 and the lower screw coupling part 330.

Next, the bus bar 400 is provided to connect the phases of the distribution board and the circuit breaker. The bus bar 400 is formed of a metal piece having a screw hole 401 for terminal connection on both sides thereof, and inserted into the through hole 310 to be fastened.

Here, one of the screw holes 401 formed on both sides of the bus bar 400 may be connected to the one-phase terminal of the distribution board and the other one may be connected to the one-phase terminal of the breaker.

For example, when the circuit breaker has terminals of three-phase or four-phase, three or four bus bars are connected in parallel to one circuit breaker, and information of each phase is detected by a sensor built in the current- So that it can be detected independently.

The second housing 500 is provided at the top and rear sides of the second housing 500 with a sliding wing 510 protruding outward to correspond to the sliding slot 320 and slidingly coupled to the sliding slot 320.

At the center of the bottom surface of the lower block 120, the lower surface of the adhesive plate 210, the lower surface of the socket 300, and the upper surface of the bus bar 400 and the upper surface of the second housing 500, (Not shown) formed at both ends of the threaded column so as to be movable along the longitudinal direction of the threaded column, and is inserted into the first housing (not shown) And a coupling nut (not shown) for coupling the contact plate 210, the socket 300, and the second housing 500 together.

As described above, according to the present invention, the magnetic field formed around the sensor due to the presence of the bus bar and the external magnetic field adjacent to the sensor is blocked, thereby minimizing the influence thereof, thereby preventing malfunction of the sensor, There is an effect.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments.

100: first housing 110: upper block
120: lower block 130: upper screw fastening part
140: protrusion projection 150: substrate portion
150-1: first substrate 150-2: second substrate
150-3: Third substrate 151: Hall sensor
152: sensing part 200: shielding part
210: tight contact plate 220:
230: cover plate 300: socket
310: through hole 320: slide slot
330: Lower screw fastening part 400: Bus bar
401: screw hole 500: second housing
510: sliding wing

Claims (5)

Shaped insulating block which is divided into a stepped top block having one step and a straight bottom block vertically fixed to the bottom center of the upper block, and the upper block is formed of a T- Wherein the lower block has an upper screw engagement part projecting in a cylindrical shape on an inner side surface positioned in a straight line with both sides of the lower end face, and a protrusion protruding at a predetermined height is formed on an upper outer side surface of the lower block, housing;
A shielding portion installed to surround the outside of the lower block excluding the protrusions, the outer surface of the shielding portion not forming a step with the protrusions;
A through hole is formed at both lower ends in the longitudinal direction, and a slide slot is formed at a predetermined depth on the upper and lower surfaces of the front and rear surfaces in the direction perpendicular to the longitudinal direction, A socket having a lower screw engagement portion formed in a cylindrical shape so as to protrude from the outer surface at a position corresponding to a straight line with the screw engagement portion;
A bus bar provided on both sides with metal balls formed with screw holes to be inserted and fastened to the through holes; And
And a second housing protruding outwardly from the upper and lower surfaces of the housing so as to correspond to the slide slots, the sliding wings being slidably coupled to the slide slots,
A Hall sensor for sensing a current flowing through the bus bar and a substrate part formed in contact with the bus bar to detect voltage information are accommodated in an inner space of the lower block, A current sensing module having a magnetic shield structure disposed to face the surface. The method according to claim 1,
The shielding portion
An adhesive plate formed to be in close contact with an outer bottom surface of the lower block;
A banding piece formed at each of upper, lower, left and right sides of the close-contact plate and bent at a predetermined angle; And
And a cover plate extending from the bending part to press the outer surface of the lower block. ≪ Desc / Clms Page number 19 > The method according to claim 1,
The substrate portion includes:
A first substrate having an upper surface on which the Hall sensor is formed facing the inner bottom surface of the lower block,
A second substrate disposed on both sides of the bottom surface of the first substrate so as to face the inner bottom surface of the bottom block,
A communication module disposed perpendicularly to the second substrate so as to be symmetrical with respect to the center of the upper surface of the second substrate and communicating with an external network; And a third module including a connection module for mediating data transmission / reception between the communication module and the control module. 3. The method of claim 2,
Wherein a contact hole is formed at a bottom surface of the lower block and at a position corresponding to the sensing piece of the fastening plate, respectively. 3. The method of claim 2,
A coupling hole having the same size is formed at the center of each of the bottom surface of the lower block, the lower surface of the contact plate, the lower surface of the socket, and the upper surface of the bus bar and the second housing, And a fastening nut fastened to both ends of the threaded column so as to be movable along the longitudinal direction of the threaded column to couple the first housing, the fastening plate, the socket and the second housing together. And a magnetic field shielding structure.

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