Anti-magnetic shunt, its power meter and method for manufacturing the anti-magnetic shunt

Abstract

The present invention relates to an anti-magnetic shunt, its power meter and a manufacturing method of the anti-magnetic shunt, which includes a sheet-shaped shunt and a sheet-shaped connecting piece. The sheet-shaped shunt includes a current inflow end, a resistor body, and a current outflow end that are electrically connected in sequence; a separation groove is provided on the resistor body to divide the effective resistor body into two effective resistor bodies with the same area: an upper half effective resistor body and a lower half effective resistor body; the sheet-shaped shunt is provided with a voltage end, a first sampling end, and a second sampling end. The sheet-shaped connecting piece passes through the separation groove and includes an upper side body corresponding to the area of the upper half effective resistor body, a bent piece, and a lower side body that connects the bent piece and further extends to the other side of the resistor body and corresponds to the area of the lower half effective resistor body; a sampling extension end electrically connected to the first sampling end is provided on the lower side body of the connecting piece, and a connecting end extends upward from the upper side body. In this way, the anti-magnetic accuracy of the instrument load current at the milliampere level is improved.

Description

Technical Field

[0001] The present invention relates to an anti-magnetic shunt for power instruments, its power meter and a manufacturing method of the anti-magnetic shunt, in particular to an anti-magnetic shunt for the field of electric energy transmission, its power meter and a manufacturing method of the anti-magnetic shunt. Background Art

[0002] At present, the advantages of high metering accuracy, small temperature influence and low cost of shunts are widely used in single-phase smart energy meters, especially manganin shunts; due to the installation position of the shunt and the characteristics of the connecting sampling wires, the manganin shunt will generate induced current when affected by power frequency magnetic field interference, which will seriously affect the accuracy of the metering current.

[0003] The traditional manganin shunt samples current through a piece of manganin alloy, and the wiring is relatively scattered. The twisted pair of the new shunt needs to be fixed in position by gluing or fixed in shape by heat shrinkable tube to prevent it from loosening, which is not only time-consuming and laborious, but also not conducive to automated production. In 2013, the State Grid Corporation of China revised the enterprise standard of energy meters. In the influence quantity test of Q / GDW1364-2013 "Technical Specification for Single-Phase Smart Energy Meters", a new item was added: "When the voltage circuit of the energy meter is energized with 115% Un and the current circuit has no current, a 0.5 mT power frequency magnetic field is applied to the most sensitive part of the energy meter affected by the magnetic field, and within 20 times the theoretical starting time, the energy meter should not generate more than 1 pulse output". The proposal of this standard has prompted the energy meter industry to actively seek solutions to improve the anti-electromagnetic interference ability of energy meters.

[0004] At present, according to the latest domestic and foreign requirements of the energy meter industry, higher requirements are put forward for the anti-magnetic interference ability of energy meters with small working current. Especially when the working current is 20 mA or less, in the face of magnetic field interference with an intensity of 0.5 mT from an uncertain direction, how to improve the accuracy of power detection is an urgent problem in the industry.

[0005] Therefore, it is necessary to optimize and improve the anti-magnetic shunt and its power meter to improve the ability of the shunt to resist power frequency magnetic field interference. Summary of the Invention

[0006] The purpose of the present invention is to provide an anti-magnetic shunt capable of resisting power frequency magnetic field interference under a small working current, its power meter and a manufacturing method of the anti-magnetic shunt.

[0007] To achieve the above technical objectives, the present invention adopts the following technical means: An anti-magnetic shunt includes a sheet-shaped shunt and a sheet-shaped connecting piece. The sheet-shaped shunt includes a current inlet end, a resistor body, and a current outlet end that are electrically connected in sequence. Along the direction of the current flowing through the resistor body, a partition groove is provided on the resistor body. The partition groove divides the effective resistor body into two effective resistor bodies with the same area, forming an upper half effective resistor body and a lower half effective resistor body along the direction of the current flow. The sheet-shaped shunt is sequentially provided with a voltage terminal, a first sampling terminal, and a second sampling terminal along the direction of the current flow. The first sampling terminal is provided on the lower side of the connection between the current inlet end and the lower half effective resistor body, and the second sampling terminal is provided on the upper side of the connection between the current outlet end and the upper half effective resistor body. The sheet-shaped connecting piece passes through the partition groove and includes an upper side body corresponding to the area of the upper half effective resistor body, a bent piece connecting the upper side body and passing through the partition groove, and a lower side body connecting the bent piece and further extending to the other side of the effective resistor body and corresponding to the area of the lower half effective resistor body. A sampling extension terminal electrically connected to the first sampling terminal is provided on the lower side body of the connecting piece, and a connection terminal extends upward from the upper side body.

[0008] As a further improvement of the present invention, the upper half effective resistor body and the lower half effective resistor body are located on the same plane.

[0009] As a further improvement of the present invention, the width of the sheet-shaped connecting piece is the same as that of the effective resistor body.

[0010] As a further improvement of the present invention, the first sampling terminal and the second sampling terminal are provided on the upper and lower end faces of the sheet-shaped shunt.

[0011] As a further improvement of the present invention, the first sampling terminal laterally extends to the lower side of the lower half effective resistor body, and the sampling extension terminal extends downward from the lower side body to achieve electrical connection with the first sampling terminal.

[0012] As a further improvement of the present invention, a concave part and a convex part that cooperate with each other are provided between the first sampling terminal and the sampling extension terminal for positioning connection.

[0013] As a further improvement of the present invention, the voltage terminal extends upward from the upper side end face of the current inlet end, and the voltage terminal, the connection terminal, and the second sampling terminal are all located at the upper end of the sheet-shaped shunt.

[0014] As a further improvement of the present invention, the voltage terminal, the connection terminal, and the second sampling terminal are used to be plugged into a PCB board or connected to a twisted pair sampling line for extension.

[0015] To achieve the above technical objectives, the present invention can also adopt the following technical means:

[0016] An electric power meter comprises an electric power meter housing and the above-mentioned anti-magnetic field shunt located in the electric power meter housing.

[0017] To achieve the above technical objectives, the present invention may also adopt the following technical means:

[0018] A method for manufacturing an anti-magnetic field shunt comprises separately manufacturing the above-mentioned sheet-shaped shunt and sheet-shaped connecting sheet;

[0019] Passing the sheet-shaped connecting sheet through the separation groove and installing it on the sheet-shaped diverter;

[0020] Electrically fix the first sampling end and the sampling extension end between the sheet-shaped current divider and the sheet-shaped connecting sheet;

[0021] The voltage end of the sheet-shaped shunt, the connection end of the sheet-shaped connecting sheet and the second sampling end of the sheet-shaped shunt are plugged into the PCB board or connected to the twisted pair sampling line extension.

[0022] Compared with the prior art, the anti-magnetic field shunt of the present invention is provided with a dividing groove on the effective resistor along the flow direction of the current flowing through the resistor, and the dividing groove divides the effective resistor into two effective resistors with the same area, forming an upper half effective resistor and a lower half effective resistor along the current flow direction, and the sheet-like connecting piece is passed through the dividing groove, including an upper side sheet corresponding to the area of ​​the upper half effective resistor, a bending sheet connected to the upper side sheet and passed through the dividing groove, and a lower side sheet connected to the bending sheet and further extended to the other side of the effective resistor and corresponding to the area of ​​the lower half effective resistor. With such an arrangement, the anti-magnetic field shunt has strong anti-interference ability and high reliability. Even when the anti-magnetic field shunt is used for extremely small working current, the accuracy difference of the electric meter can be extremely small in the face of strong magnetic field interference. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a structural schematic diagram of the anti-magnetic field shunt of the present invention;

[0024] Figure 2 yes Figure 1 Schematic diagram of the structure from another angle.

[0025] Figure 3 yes Figure 1 Schematic diagram of the structure from another angle.

[0026] Figure 4 This is a schematic diagram of the structure of the anti-magnetic field shunt of the present invention.

[0027] Figure 5 It is a side view of the anti-magnetic field shunt of the present invention.

[0028] Figure 6 yes Figure 5Schematic diagram of the structural decomposition.

[0029] Figure 7 This is the top view of the anti-magnetic shunt of the present invention.

[0030] Figure 8 This is the schematic diagram of the structure of the anti-magnetic shunt of the present invention installed on the PCB board.

[0031] Figure 9 Is Figure 8 Schematic diagram of the structural decomposition.

[0032] Figure 10 Is Figure 8 Side view.

[0033] Figure 11 Is Figure 8 Front view.

[0034] Figure 12 Is Figure 8 Rear view.

[0035] Reference numerals:

[0036] Anti-magnetic shunt 100

[0037] Current inflow end 11 of shunt 1

[0038] Voltage terminal 111, First sampling terminal 112

[0039] Convex portion 1121, Connection hole 113

[0040] Resistor body 12, Upper half effective resistor body 121

[0041] Partition groove 122, Lower half effective resistor body 123

[0042] Current outflow end 13, Second sampling terminal 131

[0043] Connection hole 132, Connection piece 2

[0044] Upper side plate body 21, Connection end 211

[0045] Bent piece 22, Lower side plate body 23

[0046] Sampling extension end 231, Concave portion 232

[0047] Circuit board 200, Insertion hole 201 Detailed implementation manner

[0048] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that: unless otherwise specifically stated, the relative arrangements of components and steps, numerical expressions and values set forth in these embodiments do not limit the scope of the present invention.

[0049] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way a limitation on the present invention, its application, or its use.

[0050] Technologies and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, such technologies and devices should be regarded as part of the specification.

[0051] In all the examples shown and discussed herein, any specific values should be construed as merely exemplary and not as a limitation. Thus, other examples of the exemplary embodiments may have different values.

[0052] It should be noted that: like reference numerals and letters denote like items in the following drawings, and thus, once an item is defined in one drawing, further discussion thereof is not required in subsequent drawings.

[0053] In the field of shunt applications, as a supplier familiar with market demands in the industry, Weida Electronics Co., Ltd. is well aware of the problems existing in the prior art. Its R & D team has further invested heavily on the basis of its own original technologies, conducted long-term and extensive experiments, scheme screening, and extensive customer surveys, and finally obtained the technical solution of the present invention.

[0054] Please refer Figures 1 to 12 As shown, it is a schematic structural diagram of the anti-magnetic field shunt 100 of the present invention. An anti-magnetic field shunt 100 of the present invention mainly includes a sheet-shaped shunt 1 and a sheet-shaped connecting piece 2.

[0055] The sheet-shaped shunt 1 comprises a current inflow end 11, a resistor 12, and a current outflow end 13 which are electrically connected in sequence; a separation groove 122 is provided on the resistor 12 along the flow direction of the current flowing through the resistor 12, and the separation groove 122 divides the effective resistor 12 into two effective resistors 12 with the same area, forming an upper half effective resistor 121 and a lower half effective resistor 123 along the flow direction of the current; the sheet-shaped shunt 1 is provided with a voltage end 111, a first sampling end 112, a second sampling end 131 in sequence along the flow direction of the current , the first sampling end 112 is arranged at the lower side of the connection between the current inflow end 11 and the lower half effective resistor 123, that is, the first sampling end 112 can be arranged at the current inflow end 11, the resistor 12 or the junction of the current inflow end 11 and the resistor 12 in different implementations, and the second sampling end 131 is arranged at the upper side of the connection between the current outflow end 13 and the upper half effective resistor 121, that is, the second sampling end 131 can be arranged at the current outflow end 13, the resistor 12 or the junction of the current outflow end 13 and the resistor 12 in different implementations;

[0056] The sheet-like connecting piece 2 is inserted into the dividing groove 122, and includes an upper sheet 21 having an area corresponding to that of the upper half effective resistor 121, a bent sheet 22 connected to the upper sheet 21 and inserted into the dividing groove 122, and a lower sheet 23 connected to the bent sheet 22 and further extending to the other side of the effective resistor 12 and having an area corresponding to that of the lower half effective resistor 123; the lower sheet 23 of the connecting piece 2 is provided with a sampling extension end 231 electrically connected to the first sampling end 112, and the upper sheet 21 has a connecting end 211 extending upward. With such arrangement, the sheet-like connecting piece 2 forms a twisted pair with the upper and lower semi-effective resistors 121 and 123. The current generated by the resistor 12 cutting the magnetic flux lines can offset the current generated by the sheet-like connecting piece 2 cutting the magnetic flux lines, and can resist external alternating magnetic fields at any angles, that is, it can resist interference from external alternating magnetic fields on six projection planes. Even when the anti-magnetic field shunt 100 is applied to extremely small working currents and faces strong magnetic field interference, the accuracy difference of the electric meter can still be extremely small. For example, at an operating current of 20mA or less and a magnetic field interference of 0.5mT, the electric meter accuracy error of the anti-magnetic field shunt 100 can be less than 10%. In this way, the electric meter can achieve excellent resistance to magnetic field interference at extremely small working currents.

[0057] The upper half effective resistor 121 and the lower half effective resistor 123 are located in the same plane. This arrangement facilitates the manufacture of the sheet-shaped shunt 1 .

[0058] The width of the sheet-shaped connecting piece 2 is the same as that of the effective resistor body 12. The width can refer to the up-down width or the left-right width. With such a setting, the connecting piece 2 and the effective resistor body 12 can achieve a better cancellation effect in the face of alternating magnetic field interference in all directions, improving the accuracy of the anti-magnetic shunt 100.

[0059] The side of the sheet-shaped connecting piece 2 is Z-shaped. That is, when viewed from the left-right direction, the cross-section of the sheet-shaped connecting piece 2 is approximately Z-shaped. In this way, the sheet-shaped connecting piece 2 only needs to be formed by bending both sides of a flat sheet-shaped metal, which is convenient for manufacturing.

[0060] In this embodiment, the first sampling end 112 and the second sampling end 131 are arranged on the upper and lower end faces of the sheet-shaped shunt 1. With such a setting, the sheet-shaped shunt 1 can be formed by shearing a flat sheet-shaped metal, without the need for additional welding or forming by die-casting, etc., which is convenient for manufacturing.

[0061] The first sampling end 112 extends downward from the lower end face of the current inflow end 11 and then further extends laterally to the lower side of the lower half effective resistor body 123. The sampling extension end 231 extends downward from the lower side sheet body 23 and is electrically connected to the first sampling end 112. With such a setting, the first sampling end 112 and the sampling extension end 231 are respectively located on the lower sides of the effective resistor body 12 and the lower side sheet body 23, which is convenient for manufacturing and assembly, and from all angles, it is beneficial to achieve a better cancellation effect of external alternating magnetic field interference.

[0062] A concave portion 232 and a convex portion 1121 that cooperate with each other are provided between the first sampling end 112 and the sampling extension end 231. That is, in different embodiments, the concave portion 232 and the convex portion 1121 can be interchanged as long as the plug-in positioning effect can be achieved. With such a setting, the first sampling end 112 and the sampling extension end 231 can be electrically held through the mutually inserted concave portion 232 and convex portion 1121. Preferably, welding or riveting positioning can also be performed on this basis.

[0063] The voltage end 111 extends upward from the upper side end face of the current inflow end 11. The voltage end 111, the connection end 211, and the second sampling end 131 are all located at the upper end of the sheet-shaped shunt 1. With such a setting, the voltage end 111, the connection end 211, and the second sampling end 131 can uniformly transmit signals outward at the upper end of the sheet-shaped shunt 1, which is convenient for collecting the required signals.

[0064] Specifically, the voltage terminal 111, the connection terminal 211, and the second sampling terminal 131 are used to plug or connect to a twisted sampling wire and extend it to the circuit board 200. The circuit board 200 is provided with plug holes 201. The voltage terminal 111, the connection terminal 211, and the second sampling terminal 131 respectively plug or connect to the twisted sampling wire and extend it to the plug holes 201. Filtering elements, AD chips, etc. are arranged on the circuit board 200, which is convenient for timely converting electrical signals into digital signals and is not affected by external alternating magnetic fields.

[0065] Connection holes 113 and 132 are provided on the current inflow end 11 and the current outflow end 13 of the shunt 1, so as to install terminal blocks (not shown). In other embodiments, the current inflow end 11 and the current outflow end 13 can directly integrally extend a connection terminal (not shown) for connecting a cable.

[0066] The present invention also protects a power meter (not shown), which includes a power meter housing (not shown) and the anti-magnetic field shunt 100 located inside the power meter housing. The main core component of the power meter lies in the anti-magnetic field interference of the anti-magnetic field shunt 100. The anti-magnetic field interference of the anti-magnetic field shunt 100 under the conditions of small working current and high magnetic field interference enables the power meter to have excellent power data detection accuracy, giving the power meter a core market competitive advantage.

[0067] The present invention also protects a manufacturing method of the anti-magnetic field shunt 100. The sheet-shaped shunt 1 and the sheet-shaped connection piece 2 are respectively manufactured; the sheet-shaped connection piece 2 is passed through the partition groove 122 and attached to the sheet-shaped shunt 1; the first sampling end 112 and the sampling extension end 231 between the sheet-shaped shunt 1 and the sheet-shaped connection piece 2 are electrically fixed; the voltage terminal 111 of the sheet-shaped shunt 1, the connection terminal 211 of the sheet-shaped connection piece 2, and the second sampling terminal 131 of the sheet-shaped shunt 1 are plugged or connected to a twisted sampling wire and extended to the circuit board 200. The above steps are not limited in order. With such a setting, the sheet-shaped shunt 1, the sheet-shaped connection piece 2, and the installation method therebetween can enable the anti-magnetic field shunt 100 to have excellent anti-magnetic field interference under the conditions of small working current and high magnetic field interference, improving the accuracy of power data detection of the power meter.

[0068] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this invention belongs. The terms used in the description of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "or / and" used herein includes any and all combinations of one or more of the related listed items.

[0069] A series of orientation terms such as front, back, left, right, up, and down used for the technical features of the above-described embodiments are only used for convenient description and understanding of the technical features, and do not constitute a limitation on the specific direction in the actual use of the technical solution.

[0070] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered to be within the scope described in this specification.

[0071] The above-described embodiments only represent several implementation manners of the present invention, and the description thereof is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention patent shall be subject to the appended claims.

Claims

1. An anti-magnetic shunt, characterized in that: It includes a sheet-shaped shunt and a metal sheet-shaped connecting piece. The sheet-shaped shunt includes a current inflow end, a resistor body, and a current outflow end that are electrically connected in sequence. A separation groove is provided on the resistor body along the direction of current flowing through the resistor body. The separation groove divides the effective resistor body into two effective resistor bodies with the same area, forming an upper half effective resistor body and a lower half effective resistor body along the direction of current flow. The sheet-shaped shunt is sequentially provided with a voltage end, a first sampling end, and a second sampling end along the direction of current flow. The first sampling end is provided on the lower side of the connection between the current inflow end and the lower half effective resistor body, and the second sampling end is provided on the upper side of the connection between the current outflow end and the upper half effective resistor body. The sheet-shaped connecting piece passes through the separation groove and includes an upper side body corresponding to the area of the upper half effective resistor body, a bent piece connecting the upper side body and passing through the separation groove, and a lower side body connecting the bent piece and further extending to the other side of the effective resistor body and corresponding to the area of the lower half effective resistor body. The upper side body, the bent piece, and the lower side body are insulated from the effective resistor body. A sampling extension end electrically connected to the first sampling end is provided on the lower side body of the connecting piece, and a connection end extends upward from the upper side body.

2. The anti-magnetic shunt according to claim 1, characterized in that: The upper half effective resistor body and the lower half effective resistor body are located in the same plane.

3. The anti-magnetic shunt according to claim 1, characterized in that: The width of the sheet-shaped connecting piece is the same as that of the effective resistor body.

4. A magnetic field shunt according to claim 1, wherein: The first sampling end and the second sampling end are provided on the upper and lower end faces of the sheet-shaped shunt.

5. An anti-magnetic shunt according to claim 1, characterized in that: The first sampling end laterally extends to the lower side of the lower half effective resistor body, and the sampling extension end extends downward from the lower side body and is electrically connected to the first sampling end.

6. The anti-magnetic shunt according to claim 5, characterized in that: A concave part and a convex part that cooperate with each other are provided between the first sampling end and the sampling extension end.

7. An anti-magnetic shunt according to claim 1, characterized in that: The voltage end extends upward from the upper side end face of the current inflow end. The voltage end, the connection end, and the second sampling end are all located at the upper end of the sheet-shaped shunt.

8. The anti-magnetic shunt according to claim 7, characterized in that: The voltage end, the connection end, and the second sampling end are used for plugging into a PCB board or connecting a twisted pair sampling wire to extend.

9. An electric meter, characterized in that: It includes a power meter housing and the anti-magnetic shunt according to any one of claims 1 to 8 located inside the power meter housing.

10. A manufacturing method of an anti-magnetic shunt, characterized in that: It includes manufacturing the sheet-shaped shunt and the sheet-shaped connecting piece according to any one of claims 1 to 8 respectively. Pass the sheet-shaped connecting piece through the separation groove and attach it to the sheet-shaped shunt for installation. Electrically hold the first sampling end and the sampling extension end between the sheet-shaped shunt and the sheet-shaped connecting piece. Plug the voltage end of the sheet-shaped shunt, the connection end of the sheet-shaped connecting piece, and the second sampling end of the sheet-shaped shunt into a PCB board or connect a twisted pair sampling wire to extend.

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