Electronic current transformer for resisting electromagnetic interference by adopting damping method

Abstract

The invention discloses an electronic current transformer for resisting electromagnetic interference by adopting a damping method, and relates to the technical field of current transformers. The problem that the measurement precision of an existing mutual inductor is reduced due to the fact that the capacity of resisting external electromagnetic interference is insufficient is solved. Comprising a shell in which a coil is fixedly connected; the two magnetic rings are fixedly connected to the interior of the shell and located on the two sides of the coil respectively; the first shielding layer is fixedly connected in the shell, a second shielding layer and a third shielding layer are fixedly connected in the shell, and the maximum distances between the first shielding layer, the second shielding layer and the third shielding layer and the central axis of the shell are sequentially reduced. The magnetic ring and the shielding layer are matched to process external high-frequency and low-frequency electromagnetism, electromagnetic energy of external electromagnetic interference is converted into heat energy to be consumed, the influence of the external electromagnetism on the coil is reduced, and then the measurement precision of the coil is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of current transformers, and in particular to an electronic current transformer which adopts a damping method to resist electromagnetic interference. Background Art

[0002] The instrument transformer is a commonly used electrical signal measurement device in the power grid. It is mainly used to measure current, voltage and electric energy, monitor the key operating status of the power system, and ensure the safe operation of the power grid. Traditional instrument transformers are mainly based on electromagnetic or voltage divider measurement technology. With the development of intelligent sensing technology and digital signal processing technology, electronic instrument transformers have gradually matured. Electronic instrument transformers have the advantages of excellent insulation performance, fast response speed, high degree of integration and digitization, etc., which are more in line with the development needs of digitalization and intelligence of power grids.

[0003] In actual use, electromagnetic interference is one of the main reasons affecting the measurement accuracy of electronic transformers. In the case of circuits at the switch operation installation location, lightning strikes and system short circuits, transient strong electromagnetic interference will be generated on the transformer. These interferences affect the electronic transformer through direct conduction or electromagnetic field coupling, reducing its measurement accuracy, increasing measurement errors, and even causing equipment damage. Although the electronic transformer has passed the electromagnetic compatibility test, in actual applications, since the intensity of the actual interference signal far exceeds the level specified by the standard, the transformer will still have electromagnetic protection failures during operation, resulting in reduced measurement accuracy of the transformer. Summary of the invention

[0004] The present invention provides an electronic current transformer which adopts a damping method to resist electromagnetic interference, so as to overcome the disadvantage that the existing transformer has insufficient ability to resist external electromagnetic interference, resulting in reduced measurement accuracy of the transformer.

[0005] The technical solution of the present invention is: an electronic current transformer that adopts a damping method to resist electromagnetic interference, comprising: a shell, in which a coil is fixedly connected; two magnetic rings, fixedly connected to the shell and respectively located on both sides of the coil; a first shielding layer, fixedly connected to the shell, in which a second shielding layer and a third shielding layer are fixedly connected, the maximum distances between the first shielding layer, the second shielding layer and the third shielding layer and the central axis of the shell decrease successively, and the coil and the magnetic ring are both located on the inner side of the third shielding layer.

[0006] Furthermore, the first shielding layer and the third shielding layer are both made of materials with high electrical conductivity, and the second shielding layer is made of material with high magnetic permeability.

[0007] Furthermore, it also includes: two installation rings fixedly connected to the inner side of the shell in opposite directions; and two shielding nets fixedly connected to the opposite sides of the two installation rings.

[0008] Furthermore, it also includes: two groups of gathering mechanisms, respectively arranged on adjacent mounting rings, the gathering mechanisms are used to gather the wires, and the gathering mechanisms include: an extrusion piece, which is limitedly and slidably connected to the mounting ring, the extrusion piece is fixedly connected with an elastic ring, a side of the elastic ring close to the mounting ring is fixedly connected with a plurality of gathering pieces, a bending portion is provided at a position of the gathering piece away from the mounting ring, an extrusion block is fixedly connected to a position of the gathering piece away from the central axis of the shell, the extrusion block is extrusion-matched with the mounting ring, and the gathering piece is fixedly connected to the shielding net at a position away from the mounting ring.

[0009] Furthermore, it also includes: a plurality of intermediate pressure parts, all of which are fixedly connected between the two elastic rings.

[0010] Furthermore, it also includes: main arc-shaped parts whose number is equal to that of the folding parts, which are fixed in pairs to adjacent positions of the folding parts close to the bending part, and the main arc-shaped parts are provided with a hook part at a position away from the adjacent folding parts and close to the central axis of the shell; secondary arc-shaped parts whose number is equal to that of the folding parts, which are fixed in pairs to adjacent positions of the folding parts close to the bending part, and a plurality of limiting grooves are provided on the side of the secondary arc-shaped parts away from the central axis of the shell, and the limiting grooves are matched with the adjacent said hook part.

[0011] Furthermore, the folding member fixedly connected to the main arc-shaped member and the folding member fixedly connected to the secondary arc-shaped member are in an alternating distribution state, and the distance between the adjacent extrusion blocks of the main arc-shaped member and the adjacent elastic rings is greater than the distance between the adjacent extrusion blocks of the secondary arc-shaped member and the adjacent elastic rings.

[0012] Furthermore, it also includes: a number of heat-conducting wires equal to the gathering pieces, which are respectively fixed to the shell near the gathering pieces, and one end of which is fixed to the first shielding layer, and the other end passes through the mounting ring and is fixed to the shielding net.

[0013] Furthermore, it also includes: a fixed seat, which is arranged on the shell; two limiting members distributed symmetrically around the center, both of which are limitedly slidably connected to the fixed seat, and a spring is fixed between the two limiting members, and the limiting members are limitedly matched with the shell.

[0014] Furthermore, a first inclined surface is provided on the limiting member, and a second inclined surface and a third inclined surface are provided on the shell near the fixing seat, the second inclined surface is pressed and fitted with the first inclined surface, and the third inclined surface is pressed and fitted with the limiting member.

[0015] Compared with the prior art, the present invention has the following advantages: the present invention utilizes the cooperation of the magnetic ring and the shielding layer to process external high-frequency and low-frequency electromagnetic respectively, converts the electromagnetic energy of external electromagnetic interference into heat energy and consumes it, reduces the influence of external electromagnetic on the coil, and thus ensures the measurement accuracy of the coil; utilizes the shielding net to block the gap between the shell and the wire, prevents external electromagnetic from interfering with the coil through the gap between the shell and the wire; utilizes the swing of the gathering piece and the deformation of the medium-pressure piece to gather the wire to the middle of the shell, so that the distance between the wire and the coil is roughly consistent, improves the uniformity of the magnetic field of the wire at various locations of the coil, and thus improves the measurement accuracy of the coil. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention; Figure 2 It is a three-dimensional structural schematic diagram of the housing, the shielding net and the extruded part of the present invention; Figure 3 It is a schematic diagram of the three-dimensional structure of the housing, the mounting ring and the shielding net of the present invention; Figure 4 It is a three-dimensional structural cross-sectional view of the housing, coil and magnetic ring of the present invention; Figure 5 The present invention is attached Figure 4 The enlarged view of point A in the middle; Figure 6 An exploded view of the mounting ring, shielding mesh and extrusion of the present invention; Figure 7 It is a three-dimensional structural schematic diagram of the mounting ring, the gathering member and the extrusion block of the present invention; Figure 8 It is a schematic diagram of the three-dimensional structure of the gathering piece, the extrusion block and the main arc-shaped piece of the present invention; Fig. 9 It is a schematic diagram of the three-dimensional structure of the housing, the shielding net and the heat-conducting wire of the present invention; Fig.10 It is a three-dimensional structural schematic diagram of the housing, the fixing seat and the limiting member of the present invention.

[0017] Figure numbers: 1-shell, 2-coil, 3-magnetic ring, 4-first shielding layer, 5-second shielding layer, 6-third shielding layer, 7-mounting ring, 8-shielding net, 9-extruded part, 10-elastic ring, 11-gathering part, 111-bending part, 12-extrusion block, 13-medium pressure part, 14-main arc part, 141-hook part, 15-secondary arc part, 151-limiting groove, 16-thermal wire, 17-fixing seat, 18-limiting part, 181-first inclined surface, 182-second inclined surface, 183-third inclined surface. DETAILED DESCRIPTION

[0018] In order to make the above features and advantages of the present invention more easily understood, embodiments are given below with reference to the accompanying drawings for detailed description, but the present invention is not limited thereto.

[0019] An electronic current transformer that uses a damping method to resist electromagnetic interference, see Figure 1-Figure 5 , comprising: a shell 1, in which a coil 2 is fixed; two magnetic rings 3, fixed in the shell 1 and respectively located on both sides of the coil 2; a first shielding layer 4, fixed in the shell 1, in which a second shielding layer 5 and a third shielding layer 6 are fixed, the maximum distances between the first shielding layer 4, the second shielding layer 5 and the third shielding layer 6 and the central axis of the shell 1 decrease successively, and the coil 2 and the magnetic ring 3 are both located on the inner side of the third shielding layer 6; the first shielding layer 4 and the third shielding layer 6 are both made of materials with high electrical conductivity, and the second shielding layer 5 is made of material with high magnetic permeability.

[0020] In the above scheme, the problem of insufficient ability of the existing current transformer to resist external electromagnetic interference is solved; in this scheme, the magnetic ring 3, the first shielding layer 4, the second shielding layer 5 and the third shielding layer 6 are used to respectively process the external high and low frequency electromagnetic, and the electromagnetic energy of the external electromagnetic interference is converted into heat energy and consumed, thereby reducing the influence of the external electromagnetic on the coil 2; the material of the coil 2 can be a magnetic material with high magnetic permeability, high loss, good high frequency characteristics, and not easy to saturate (ferrite material is selected here, which is sensitive to high frequency electromagnetic signals, and the influence on the system under the power frequency condition can be ignored, thereby suppressing the interference of high frequency electromagnetic); the outer side of the magnetic ring 3 can be covered with an insulating sheath, and the sheath can be made of insulating materials such as rubber or polyurethane or polytetrafluoroethylene, which can play a vibration reduction role on the one hand to prevent the magnetic ring 3 from being damaged by vibration and impact, and on the other hand to enhance insulation; the material of the shell 1 can be modified epoxy resin, and thermal conductive insulating fillers such as boron nitride and graphene can be added to improve its thermal conductivity. At the same time, the epoxy resin casting of the shell 1 can be increased with an umbrella skirt to increase its heat dissipation surface area.

[0021] The working principle of the first shielding layer 4, the second shielding layer 5 and the third shielding layer 6 for damping electromagnetic interference is as follows: the first shielding layer 4 is used to damp high-frequency electromagnetic interference, and uses the electromagnetic field to generate eddy current loss inside the shielding metal, and converts the energy of the electromagnetic interference into heat and dissipates it; the second shielding layer 5 is used to damp low-frequency electromagnetic interference, and uses the low magnetic resistance characteristics of high magnetic permeability materials to play a shunt role on the magnetic flux, preventing the external magnetic field from inducing the internal area of ​​the second shielding layer 5, so that the external magnetic field cannot enter the second shielding layer 5, and plays a role in shielding low-frequency electromagnetic interference; the third shielding layer 6 can firstly damp high-frequency electromagnetic interference, and secondly can isolate the coil 2 from the second shielding layer 5 (because the second shielding layer 5 is made of high magnetic permeability material, if it is not effectively isolated, the magnetic flux that should flow through the coil 2 will enter the second shielding layer 5 in large quantities, so that the magnetic flux of the coil 2 is weakened, thereby making the working stability of the coil 2 worse), and finally can supplement and strengthen the effect of damping electromagnetic interference to prevent the external electromagnetic interference signal energy from being too large to saturate the first shielding layer 4.

[0022] The principle of the magnetic ring 3 suppressing high-frequency electromagnetic interference is as follows: during normal operation, the frequency in the system is the industrial frequency of 50Hz. At this time, the magnetic ring 3 does not show inductance, and the impact on the system can be ignored. The equivalent frequency of high-frequency strong electromagnetic interference is very high, above several kHz, and can reach up to tens of MHz. At this time, the magnetic ring 3 shows a large inductive reactance, and shows a significant damping effect on the electromagnetic interference. The steepness of the electromagnetic interference signal will be reduced. The larger the equivalent inductance of the magnetic ring 3, the more the steepness of the electromagnetic interference signal will be reduced; at the same time, high-frequency electromagnetic interference will generate eddy current loss in the magnetic ring 3, and the energy of the electromagnetic interference will be converted into heat and dissipated due to the damping effect of the magnetic ring 3, so the amplitude of the electromagnetic interference signal is reduced.

[0023] See also Figure 1-Figure 3 , further comprising: two mounting rings 7 fixedly connected to the inner side of the housing 1 in opposite directions; and two shielding nets 8 fixedly connected to the opposite sides of the two mounting rings 7 respectively.

[0024] In the above scheme, the shielding net 8 is used to block the gap between the shell 1 and the wire to prevent external electromagnetic interference to the coil 2 through the gap between the shell 1 and the wire; the shielding net 8 can be a pure copper high-transmittance shielding net, which can fit the surface of the wire due to its softness to block the gap between the shell 1 and the wire; the side of the shielding net 8 away from the mounting ring 7 can be fixed with an elastic insulating ring to drive one side of the shielding net 8 to retract and approach the surface of the wire; the material of the shielding net 8 can be changed according to the specific circumstances of the use scenario. For example, when the use scenario is dominated by high-frequency electromagnetics, the material of the shielding net 8 should be a material with high conductivity, and vice versa.

[0025] See also Figure 3 , Figure 4 , Figure 6 and Figure 7 , and also includes: two groups of gathering mechanisms, which are respectively arranged on adjacent mounting rings 7, the gathering mechanisms are used to gather the wires, and the gathering mechanisms include: an extrusion member 9, which is limitedly slidably connected to the mounting ring 7, the extrusion member 9 is fixedly connected with an elastic ring 10, and a plurality of gathering members 11 are fixedly connected to the side of the elastic ring 10 close to the mounting ring 7, and the gathering member 11 is provided with a bending portion 111 at a position away from the mounting ring 7, and an extrusion block 12 is fixedly connected to the position of the gathering member 11 away from the central axis of the shell 1, and the extrusion block 12 is extruded and matched with the mounting ring 7, and the gathering member 11 is fixedly connected to the shielding net 8 at a position away from the mounting ring 7.

[0026] In the above scheme, the purpose is to utilize the swing of the gathering piece 11 to assist the wire to gather to the middle part of the shell 1, so that the distance between the wire and the coil 2 at various locations is roughly consistent, avoiding errors in the measurement results caused by different magnetic fields of the wire at various locations of the coil 2; multiple gathering pieces 11 corresponding to the same mounting ring 7 are distributed in a ring shape; the curved portion 111 is used to guide the wire into between the ring-shaped gathering pieces 11 when the user inserts the wire into the shell 1; pressing portions are provided on both sides of the extrusion piece 9 away from the shell 1, so that the user can press the extrusion piece 9 into the shell 1; a wedge is fixedly connected to the position of the extrusion piece 9 near its pressing portion, and the inner side of the shell 1 is provided with recesses that are the same in number as the wedges. The groove is matched with the adjacent wedge block limiter. After the user pushes the extrusion piece 9 into the housing 1, the wedge block contacts the corresponding groove and limits the extrusion piece 9 to prevent the extrusion piece 9 from moving subsequently. The elastic ring 10 is made of elastic metal material, and a protrusion is provided at the position where the inner side thereof is fixed to the retracting piece 11, so that the protrusion on the inner side of the elastic ring 10 is deformed when the retracting piece 11 moves. The retracting piece 11 is made of elastic metal material, and the elastic coefficient of the retracting piece 11 is greater than the elastic coefficient of the elastic ring 10, so that the elastic ring 10 is deformed before the retracting piece 11. After the bending portion 111 contacts the wire, as the extrusion piece 9 continues to move into the housing 1, the retracting piece 11 is deformed.

[0027] See also Figure 1 and Figure 4 , further comprising: a plurality of intermediate pressure pieces 13 , all of which are fixedly connected between the two elastic rings 10 .

[0028] In the above scheme, the purpose is to squeeze the wire located in the middle of the shell 1 through the deformation of the medium pressure component 13, so that the distance between the wire and the coil 2 at all locations tends to be consistent; the middle part of the medium pressure component 13 is set to be arc-shaped and made of elastic metal material, ensuring that the medium pressure component 13 can bend in the direction close to the central axis of the shell 1 when squeezed, thereby squeezing the wire located in the shell 1.

[0029] See also Figure 3 and Figure 8, further comprising: main arc-shaped members 14, the number of which is equal to that of the gathering members 11, which are fixedly connected in pairs to adjacent gathering members 11 at positions close to the bending portions 111, and the main arc-shaped members 14 are provided with hook portions 141 at positions away from the adjacent gathering members 11 and close to the central axis of the shell 1; secondary arc-shaped members 15, the number of which is equal to that of the gathering members 11, which are fixedly connected in pairs to adjacent gathering members 11 at positions close to the bending portions 111, and the side of the secondary arc-shaped members 15 away from the central axis of the shell 1 is provided with a plurality of limiting grooves 151, and the limiting grooves 151 are limitedly matched with the adjacent hook portions 141; the gathering members 11 fixedly connected with the main arc-shaped members 14 and the gathering members 11 fixedly connected with the secondary arc-shaped members 15 are in an alternating distribution state, and the distance between the adjacent extrusion blocks 12 of the main arc-shaped members 14 and the adjacent elastic rings 10 is greater than the distance between the adjacent extrusion blocks 12 of the secondary arc-shaped members 15 and the adjacent elastic rings 10.

[0030] In the above scheme, the main arc-shaped member 14 and the secondary arc-shaped member 15 are used to assist the gathering member 11 in gathering the wires, and the cooperation between the hook portion 141 and the limiting groove 151 is used to prevent the subsequent wires from being disturbed by the outside world and getting stuck in the gap between adjacent gathering members 11 when moving; the shape of the hook portion 141 corresponds to the shape of the limiting groove 151, and on the same gathering member 11, the shapes of the upper limiting grooves 151 of the two secondary arc-shaped members 15 are symmetrically distributed; the distances between the extrusion blocks 12 and the elastic rings 10 on the two adjacent gathering members 11 are different, so as to realize that the gathering member 11 fixed to the secondary arc-shaped member 15 swings first, and then the gathering member 11 fixed to the main arc-shaped member 14 swings, so as to ensure that the main arc-shaped member 14 can be placed on the adjacent secondary arc-shaped member 15, and the hook portion 141 enters the corresponding limiting groove 151.

[0031] See also Figure 4 , Figure 5 and Fig. 9 , and also includes: a number of thermal conductive wires 16 equal to the gathering piece 11, which are respectively fixed to the position of the shell 1 close to the gathering piece 11, and one end of which is fixed to the first shielding layer 4, and the other end passes through the mounting ring 7 and is fixed to the shielding net 8.

[0032] In the above scheme, the purpose is to use the thermal wire 16 to conduct the heat on the first shielding layer 4 to the shielding net 8, so as to assist the first shielding layer 4 in heat dissipation; the thermal wire 16 is made of elastic material, and is fixedly connected to the inner side of the shielding net 8. The elastic coefficient of the thermal wire 16 is greater than the elastic coefficient of the shielding net 8, and the contact position between the two is located between two adjacent folding parts 11. When the folding part 11 is folded, the folding part 11 will drive one side of the shielding net 8 to fold, and at this time, wrinkles will appear on the shielding net 8. Since the deformation of the shielding net 8 will drive the thermal wire 16 to deform, and the thermal wire 16 is located between two adjacent folding parts 11, the part of the shielding net 8 located between the two adjacent folding parts 11 is in a convex state, and the part of the shielding net 8 fixedly connected to the adjacent folding part 11 is in a concave state. In this way, during the folding process of the folding part 11, the shielding net 8 is prevented from irregularly deforming and entering between the main arc part 14 and the secondary arc part 15, thereby hindering the cooperation between the hook part 141 and the limiting groove 151.

[0033] See also Figure 1 , Figure 2 and Fig.10 , and also includes: a fixed seat 17, which is arranged on the shell 1; two limiting members 18 distributed symmetrically around the center, both of which are limitedly slidably connected to the fixed seat 17, and a spring is fixedly connected between the two limiting members 18, and the limiting member 18 is limitedly matched with the shell 1; a first inclined surface 181 is arranged on the limiting member 18, and a second inclined surface 182 and a third inclined surface 183 are arranged on the shell 1 near the fixed seat 17, the second inclined surface 182 is pressed and matched with the first inclined surface 181, and the third inclined surface 183 is pressed and matched with the limiting member 18.

[0034] In the above scheme, the fixing seat 17 and the shell 1 are intended to be detachably connected, so that the user can fix the fixing seat 17 to the place of use by bolts. At the same time, the shell 1 can be rotated, so that the user can adjust the direction of the shell 1 to adapt to the different directions of the wires and reduce the bending degree of the wires; the third inclined surface 183 is used to guide the two limit members 18 to reset and fix the shell 1.

[0035] The working principle of the above-mentioned scheme during installation is as follows: when installing the device, the user first fixes the fixing seat 17 to the specified position, then passes the wire to be tested through the shell 1, and completes the connection of the wire to be tested. At this time, the user presses the two extrusion members 9 to make the two close to each other, and the extrusion member 9 drives the retracting member 11 to move together through the elastic ring 10, and the retracting member 11 drives the extrusion block 12 to move, so that the extrusion block 12 contacts with the mounting ring 7. Under the extrusion of the mounting ring 7, the extrusion block 12 drives the retracting member 11 to swing, so that the distance between adjacent bending parts 111 is gradually reduced, and the retracting member 11 drives the wire to move through the main arc member 14 and the secondary arc member 15 to gather the wires. At the same time, the retracting member 11 drives the shielding net 8 to deform, so that the shielding net 8 gradually approaches the wire, and at the same time, the distance between the two elastic rings 10 is gradually reduced and the medium-pressure member 13 is squeezed. Deformation, the medium-pressure member 13 squeezes the wire located in the shell 1 to the middle of the shell 1 until the wedge block of the extrusion member 9 corresponds to the groove on the shell 1, and the extrusion member 9 is fixed by using the cooperation between the groove in the shell 1 and the wedge block on the extrusion member 9. At this time, the user stops pressing the extrusion member 9, thereby completing the arrangement of the shielding net 8 and centering the wire to the middle of the shell 1. At this time, the user completes the wiring of the device and presses the shell 1 between the two limit members 18 to make the second inclined surface 182 squeeze the first inclined surface 181. The two limit members 18 move away from each other, compressing the spring between the two limit members 18 until the shell 1 enters between the two limit members 18. At this time, the two limit members 18 are reset and the fixation of the shell 1 is completed. The user rotates the shell 1 to follow the direction of the wire to be measured in the shell 1 to complete the installation of the device.

[0036] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An electronic current transformer using a damping method to resist electromagnetic interference, characterized in that: include: A housing (1), wherein a coil (2) is fixedly connected inside the housing (1); Two magnetic rings (3) are fixedly connected to the housing (1) and are respectively located on both sides of the coil (2); A first shielding layer (4) is fixedly connected to the shell (1), and a second shielding layer (5) and a third shielding layer (6) are fixedly connected to the shell (1). The maximum distances between the first shielding layer (4), the second shielding layer (5) and the third shielding layer (6) and the central axis of the shell (1) decrease successively, and the coil (2) and the magnetic ring (3) are both located on the inner side of the third shielding layer (6).

2. The electronic current transformer using damping method to resist electromagnetic interference according to claim 1, characterized in that: The first shielding layer (4) and the third shielding layer (6) are both made of materials with high electrical conductivity, and the second shielding layer (5) is made of material with high magnetic permeability.

3. The electronic current transformer using damping method to resist electromagnetic interference according to claim 1, characterized in that: Also includes: Two mounting rings (7) fixedly connected to the inner side of the housing (1) in opposite directions; The two shielding nets (8) are respectively fixed to opposite sides of the two mounting rings (7).

4. The electronic current transformer using damping method to resist electromagnetic interference according to claim 3, characterized in that: Also includes: Two sets of gathering mechanisms are respectively arranged on adjacent mounting rings (7), the gathering mechanisms are used to gather the wires, and the gathering mechanisms include: An extrusion member (9) is connected to the mounting ring (7) in a limited sliding manner, the extrusion member (9) is fixedly connected to an elastic ring (10), a side of the elastic ring (10) close to the mounting ring (7) is fixedly connected to a plurality of retracting members (11), a position of the retracting member (11) away from the mounting ring (7) is provided with a bending portion (111), a position of the retracting member (11) away from the central axis of the housing (1) is fixedly connected to an extrusion block (12), the extrusion block (12) is extrusion-matched with the mounting ring (7), and a position of the retracting member (11) away from the mounting ring (7) is fixedly connected to the shielding net (8).

5. The electronic current transformer using damping method to resist electromagnetic interference according to claim 4, characterized in that: Also includes: A plurality of intermediate pressure parts (13) are all fixedly connected between the two elastic rings (10).

6. The electronic current transformer using damping method to resist electromagnetic interference according to claim 4, characterized in that: Also includes: The main arc-shaped members (14) are equal in number to the folding members (11), and are fixedly connected in pairs to adjacent folding members (11) at positions close to the bending portions (111); the main arc-shaped members (14) are provided with hook portions (141) at positions away from the adjacent folding members (11) and close to the central axis of the housing (1); The secondary arc-shaped members (15) are equal in number to the folding members (11), and are fixedly connected in pairs to adjacent positions of the folding members (11) close to the bending portions (111). A plurality of limiting grooves (151) are provided on a side of the secondary arc-shaped members (15) away from the central axis of the shell (1), and the limiting grooves (151) are in limiting cooperation with adjacent curved hook portions (141).

7. The electronic current transformer using damping method to resist electromagnetic interference according to claim 6, characterized in that: The gathering piece (11) fixedly connected to the main arc-shaped piece (14) and the gathering piece (11) fixedly connected to the secondary arc-shaped piece (15) are in a staggered distribution state, and the distance between the adjacent extrusion block (12) of the main arc-shaped piece (14) and the adjacent elastic ring (10) is greater than the distance between the adjacent extrusion block (12) of the secondary arc-shaped piece (15) and the adjacent elastic ring (10).

8. The electronic current transformer using damping method to resist electromagnetic interference according to claim 6, characterized in that: Also includes: The heat conductive wires (16) whose number is equal to the gathering pieces (11) are respectively fixed to the housing (1) at positions close to the gathering pieces (11), and one end of each heat conductive wire is fixed to the first shielding layer (4), while the other end passes through the mounting ring (7) and is fixed to the shielding net (8).

9. The electronic current transformer using damping method to resist electromagnetic interference according to claim 8, characterized in that: Also includes: A fixing seat (17) disposed on the housing (1); Two centrally symmetrically distributed limiting members (18) are both slidably connected to the fixing seat (17) in a limiting manner, and a spring is fixedly connected between the two limiting members (18). The limiting members (18) are in limiting cooperation with the housing (1).

10. The electronic current transformer using damping method to resist electromagnetic interference according to claim 9, characterized in that: A first inclined surface (181) is provided on the limiting member (18), and a second inclined surface (182) and a third inclined surface (183) are provided on the housing (1) at a position close to the fixing seat (17), the second inclined surface (182) being pressed and fitted with the first inclined surface (181), and the third inclined surface (183) being pressed and fitted with the limiting member (18).

Images