A mutual inductor

Abstract

The invention discloses a mutual inductor, belonging to the field of mutual inductors. In the mutual inductor, a primary winding and a secondary winding can be connected into an integrated structure through a potting layer and a connecting layer, so that the plug-in is simple and the volume of the mutual inductor can be effectively reduced, thereby reducing the production cost. At the same time, internally filled ball particles can effectively fill the cracks on the surfaces of the connecting layer and the potting layer, thereby achieving the effect of filling and effectively inhibiting the cracks from continuing to grow. Through the correction repair layer, after the mutual inductor is connected as a whole, the correction repair layer can be melted by controlling the change in temperature, thereby deforming to adapt to the shape of the contact surface, effectively eliminating tiny gaps and bubbles on the contact surface, thereby improving the connection of the contact surface, thereby effectively controlling the discharge phenomenon caused by tiny gaps and bubbles, on the one hand improving the safety, and on the other hand improving the quality of the mutual inductor, reducing defective products, thereby significantly improving the service life of the mutual inductor.

Description

Technical Field

[0001] The present invention relates to the field of mutual inductors, and more particularly to a mutual inductor. Background Art

[0002] Transformer, also known as instrument transformer, is a general term for current transformer and voltage transformer. It can convert high voltage into low voltage and high current into low current, and is used for measurement or protection system. Its main function is to convert high voltage or high current into standard low voltage (100V) or standard low current (5A or 1A, both refer to rated value) in proportion, so as to realize the standardization and miniaturization of measuring instruments, protection equipment and automatic control equipment. At the same time, transformer can also be used to isolate high voltage system to ensure the safety of people and equipment.

[0003] In order to transmit electric energy, the power system often uses AC voltage and high current circuits to send electricity to users, which cannot be directly measured by instruments. The role of the mutual inductor is to reduce the AC voltage and high current in proportion to values ​​that can be directly measured by instruments, which is convenient for direct measurement by instruments, and at the same time provides power for relay protection and automatic devices. The mutual inductor used in the power system is a special transformer that transmits the information of high voltage and high current of the power grid to the metering, measuring instruments, relay protection and automatic devices on the secondary side of low voltage and low current. It is a contact element between the primary system and the secondary system. Its primary winding is connected to the power grid, and the secondary winding is connected to the measuring instrument, protection device, etc. The mutual inductor cooperates with the measuring instrument and metering device to measure the voltage, current and electric energy of the primary system; cooperates with the relay protection and automatic device to form electrical protection and automatic control of various faults in the power grid. The performance of the mutual inductor directly affects the accuracy of measurement and metering of the power system and the reliability of the action of the relay protection device.

[0004] The existing transformer structure does not include a primary winding, and only uses electronic wires as windings when in use. The installation method is generally to first solder the transformer to the PCB board, then pass the electronic wire through the transformer as a winding, and then solder it to the PCB board, but this structure product is large in size, the PCB plug-in production efficiency is low, and the production cost is high; and the windings of the existing transformers are generally encapsulated with epoxy resin and the shell, but the surface of the epoxy resin is very easy to crack, and the contact surface between the epoxy resin and the winding is very easy to loosen or produce larger cracks due to tiny gaps and bubbles, resulting in serious discharge of the transformer, posing a safety hazard, and also reducing the service life of the transformer. Summary of the invention

[0005] 1. Technical issues to be solved

[0006] In view of the problems existing in the prior art, the purpose of the present invention is to provide a mutual inductor, which can connect the primary winding and the secondary winding into an integrated structure through a potting layer and a connecting layer, so that the plug-in is simple and the volume of the mutual inductor can be effectively reduced, thereby reducing the production cost. At the same time, the internal ball particles can effectively fill the cracks on the surface of the connecting layer and the potting layer using epoxy resin, thereby achieving the effect of filling and effectively inhibiting the continued increase of the cracks. Through the correction repair layer, after the mutual inductor is connected as a whole, the correction repair layer can be melted by controlling the change in temperature, thereby deforming to adapt to the shape of the contact surface, effectively eliminating the tiny gaps and bubbles on the contact surface, thereby improving the connectivity of the contact surface, thereby effectively controlling the discharge phenomenon caused by tiny gaps and bubbles, on the one hand improving safety, and on the other hand improving the quality of the mutual inductor, reducing defective products, thereby significantly improving the service life of the mutual inductor.

[0007] 2. Technical solution

[0008] To solve the above problems, the present invention adopts the following technical solutions.

[0009] A mutual inductor comprises a bottom plate, a shell is provided at the upper end of the bottom plate, a magnetic core is provided in the shell, a secondary winding is wound around the outer end of the magnetic core, a potting layer is poured between the inner wall of the shell and the secondary winding, two mutually symmetrical primary windings are provided on the bottom plate, the primary winding passes through the inner circle of the magnetic core, and the lead pins of the primary winding pass through the bottom plate, a connecting layer is provided between the primary winding, the shell and the bottom plate, the primary winding, the secondary winding and the bottom plate are fixed into an integral structure through the connecting layer, and the surfaces of the primary winding and the secondary winding are provided with a correction repair layer, the two correction repair layers are respectively located at the position where the primary winding contacts the connecting layer and the position where the secondary winding contacts the potting layer, and the primary winding and the secondary winding can be connected through the potting layer and the connecting layer. The integrated structure of the level windings makes the plug-in simple and can effectively reduce the volume of the transformer, thereby reducing the production cost. At the same time, the internal ball particles can effectively fill the cracks on the surface of the connection layer and the potting layer, thereby achieving the effect of filling and effectively inhibiting the continued increase of the cracks. Through the correction repair layer, after the transformer is connected as a whole, the correction repair layer can be melted by controlling the change in temperature, so that it can deform to adapt to the shape of the contact surface, effectively eliminate the tiny gaps and bubbles on the contact surface, and then improve the connection of the contact surface, thereby effectively controlling the discharge phenomenon caused by tiny gaps and bubbles, on the one hand improving safety, on the other hand improving the quality of the transformer, reducing defective products, and thus significantly improving the service life of the transformer.

[0010] Furthermore, the primary winding adopts a single copper wire, and the copper wire passes through the inner circle of the magnetic core.

[0011] Furthermore, the magnetic core is a toroidal ultra-microcrystalline magnetic core, and the secondary winding is formed by automatic winding using a winding machine.

[0012] Furthermore, the connecting layer includes a lower connecting layer and an upper leveling layer. The upper leveling layer, the lower connecting layer and the bottom plate are connected in sequence from top to bottom. The upper leveling layer can effectively cover the surface of the lower connecting layer. On the one hand, it effectively protects the lower connecting layer, making it less likely to crack on its surface, reducing the probability of discharge and improving safety. On the other hand, even if cracks occur on the surface of the lower connecting layer, under the limiting effect of the upper leveling layer, the cracks on the surface of the lower connecting layer can be effectively suppressed from continuing to grow, thereby effectively controlling the degree of discharge and improving the service life of the transformer.

[0013] Furthermore, a plurality of inner-filling ball particles are randomly distributed inside the lower connecting layer and the potting layer, and the inner-filling ball particles include a pre-broken spherical shell and a plurality of evenly distributed positioning protrusions. The plurality of positioning protrusions are fixedly connected to the outer side of the pre-broken spherical shell, and the inner end of the pre-broken spherical shell is filled with self-repairing glue. When cracks appear on the surface of the lower connecting layer, the cracks have a force to expand outward, thereby exerting a certain pulling force on the inner-filling ball particles, causing the inner-filling ball particles near the cracks to rupture, and the self-repairing glue inside the inner-filling ball particles will flow out and fill the cracks, thereby achieving the effect of effectively controlling the cracks on the surface of the connecting layer.

[0014] Furthermore, the surface of the pre-broken spherical shell is preset with multiple evenly distributed corrective repair layers, and every two of the corrective repair layers are alternately distributed with positioning protrusions. When cracks appear on the surface of the connecting layer, the pre-broken spherical shell near the cracks is subjected to the pulling force from the cracks, and the crack-assisting grooves close to the crack side are cracked first. When the cracks extend to the inner repair ball particles, the self-repairing glue will flow to the cracks and repair the cracks. On the one hand, it can inhibit the cracks from continuing to grow, and on the other hand, it can effectively eliminate the cracks on the surface of the lower connecting layer.

[0015] Furthermore, the lower connecting layer and the potting layer are both formed by pouring epoxy resin adhesive material. The epoxy resin can achieve the effect of connecting the primary winding and the secondary winding into one while achieving the insulation effect and improving the safety.

[0016] Furthermore, the pre-broken spherical shell and the positioning protrusion are made of the same material as the connecting layer and the potting layer, and the thickness of the pre-broken spherical shell is 1-2mm. The same material can effectively improve the bonding degree between the inner supplementary ball particles and the connecting layer and the potting layer during pouring, making it difficult for bubbles to form on the contact surface between the inner supplementary ball particles and the two, thereby ensuring the quality of the connecting layer and the potting layer, and preventing cracking due to bubbles during later use.

[0017] Furthermore, the thickness of the corrective repair layer is 0.5-1mm. If the corrective repair layer is too thick, it will easily affect the bonding between the connecting layer and the primary winding, and between the potting layer and the secondary winding, resulting in a decrease in the bonding degree, making the primary winding and the potting layer easy to loosen, resulting in a decrease in the stability of the current transformer. If the corrective repair layer is too thin, its effect on filling the gap between the connecting layer and the primary winding, and between the potting layer and the secondary winding is not obvious, and the lower end surface of the corrective repair layer on the primary winding extends to the inside of the bottom plate. When the temperature is increased to soften the corrective repair layer, the amount of the softened corrective repair layer can be effectively guaranteed to prevent the impact of changes in the corrective repair layer due to state changes, and ensure that no gaps will appear between the connecting layer and the primary winding, and between the potting layer and the secondary winding before and after the state change, thereby reducing the discharge phenomenon caused by the gaps and improving safety.

[0018] Furthermore, the corrective repair layer is made of thermoplastic plastic, for example, low-density high-pressure polyethylene plastic can be used, and its melting point is 110-115°C. When the potting layer and the connecting layer are poured, the corrective repair layer can be melted within this temperature range without affecting the performance of the potting layer and the connecting layer (epoxy resin can work normally at a temperature of -50°C to 180°C), thereby adapting to the shape of the contact surface between the connecting layer and the potting layer and the primary winding and the secondary winding, and deforming, thereby effectively eliminating the tiny gaps and bubbles on the contact surface, thereby improving the connectivity of the contact surface, thereby effectively controlling the discharge phenomenon caused by tiny gaps and bubbles, on the one hand improving safety, and on the other hand improving the quality of the transformer, reducing defective products, and thus significantly improving the service life of the transformer.

[0019] 3. Beneficial effects

[0020] Compared with the prior art, the advantages of the present invention are:

[0021] (1) This scheme can connect the primary winding and the secondary winding into an integrated structure through the potting layer and the connecting layer, which makes the plug-in simple and can effectively reduce the volume of the current transformer, thereby reducing the production cost. At the same time, the internal filling ball particles can effectively fill the cracks on the surface of the connecting layer and the potting layer, thereby achieving the effect of filling and effectively inhibiting the continued increase of the cracks. Through the correction repair layer, after the current transformer is connected as a whole, the correction repair layer can be melted by controlling the change in temperature, so that it can deform to adapt to the shape of the contact surface, effectively eliminate the tiny gaps and bubbles on the contact surface, and then improve the connection of the contact surface, thereby effectively controlling the discharge phenomenon caused by tiny gaps and bubbles, on the one hand improving safety, and on the other hand improving the quality of the current transformer, reducing defective products, and thus significantly improving the service life of the current transformer.

[0022] (2) The primary winding uses a single strand of copper wire, which passes through the inner ring of the magnetic core.

[0023] (3) The magnetic core adopts a ring-shaped ultra-microcrystalline magnetic core, and the secondary winding is formed by automatic winding by a winding machine.

[0024] (4) The connection layer includes a lower connecting layer and an upper leveling layer. The upper leveling layer, the lower connecting layer and the bottom plate are connected in sequence from top to bottom. The upper leveling layer can effectively cover the surface of the lower connecting layer. On the one hand, it effectively protects the lower connecting layer, making it less likely to crack on its surface, reducing the probability of discharge and improving safety. On the other hand, even if cracks occur on the surface of the lower connecting layer, the upper leveling layer can effectively suppress the cracks on the surface of the lower connecting layer from continuing to grow, thereby effectively controlling the degree of discharge and improving the service life of the transformer.

[0025] (5) Multiple inner filling ball particles are randomly distributed inside the lower connecting layer and the potting layer. The inner filling ball particles include a pre-broken ball shell and multiple evenly distributed positioning protrusions. The multiple positioning protrusions are fixedly connected to the outer side of the pre-broken ball shell. The inner end of the pre-broken ball shell is filled with self-repairing glue. When cracks appear on the surface of the lower connecting layer, the cracks have a force that expands outward, which will produce a certain pulling force on the inner filling ball particles, causing the inner filling ball particles near the cracks to break, and the self-repairing glue inside them will flow out and fill the cracks, thereby achieving the effect of effectively controlling the cracks on the surface of the connecting layer.

[0026] (6) The surface of the pre-broken spherical shell is preset with multiple uniformly distributed correction and repair layers, with every two crack-promoting grooves and positioning protrusions distributed alternately. When cracks appear on the surface of the connecting layer, the pre-broken spherical shell near the cracks is subjected to the pulling force from the cracks, and the crack-promoting grooves close to the crack side are cracked first. When the cracks extend to the inner repair ball particles, the self-repairing glue will flow to the cracks and repair the cracks. On the one hand, it can inhibit the cracks from continuing to grow, and on the other hand, it can effectively eliminate the cracks on the surface of the lower connecting layer.

[0027] (7) Both the lower connecting layer and the potting layer are made of epoxy resin glue material. The epoxy resin can achieve the effect of connecting the primary winding and the secondary winding into one while achieving the insulation effect and improving safety.

[0028] (8) The pre-broken spherical shell and the positioning protrusion are made of the same material as the connecting layer and the potting layer, and the thickness of the pre-broken spherical shell is 1-2 mm. The same material can effectively improve the bonding degree between the inner supplementary spherical particles and the connecting layer and the potting layer during pouring, making it difficult for bubbles to form on the contact surface between the inner supplementary spherical particles and the two, thereby ensuring the quality of the connecting layer and the potting layer, and preventing cracking due to bubbles during later use.

[0029] (9) The thickness of the corrective repair layer is 0.5-1mm. If the corrective repair layer is too thick, it will easily affect the bonding between the connecting layer and the primary winding, and between the potting layer and the secondary winding, resulting in a decrease in the bonding degree, making the primary winding and the potting layer easy to loosen, resulting in a decrease in the stability of the current transformer. If the corrective repair layer is too thin, its effect on filling the gap between the connecting layer and the primary winding, and between the potting layer and the secondary winding is not obvious, and the lower end surface of the corrective repair layer on the primary winding extends to the inside of the bottom plate. When the temperature is increased to soften the corrective repair layer, the amount of the softened corrective repair layer can be effectively guaranteed, preventing the impact of the change of the corrective repair layer due to the state change, and ensuring that there will be no gaps between the connecting layer and the primary winding, and between the potting layer and the secondary winding before and after the state change, thereby reducing the discharge phenomenon caused by the gap and improving safety.

[0030] (10) The correction repair layer is made of thermoplastic plastic, for example, low-density high-pressure polyethylene plastic can be used, and its melting point is 110-115°C. After the potting layer and the connecting layer are poured, the correction repair layer can be melted within this temperature range without affecting the performance of the potting layer and the connecting layer (epoxy resin can work normally at a temperature of -50°C to 180°C), thereby adapting to the shape of the contact surface between the connecting layer and the potting layer and the primary winding and the secondary winding, and deforming, thereby effectively eliminating the tiny gaps and bubbles on the contact surface, thereby improving the connection of the contact surface, thereby effectively controlling the discharge phenomenon caused by tiny gaps and bubbles, on the one hand improving safety, and on the other hand improving the quality of the transformer, reducing defective products, and thus significantly improving the service life of the transformer. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic structural diagram of the front side of the present invention;

[0032] Figure 2 for Figure 1 The structural diagram of the section at A in the middle;

[0033] Figure 3 is a schematic structural diagram of the connection layer of the present invention;

[0034] Figure 4 A schematic diagram of the structure of the inner-supplemented sphere particles of the present invention;

[0035] Figure 5 for Figure 2 Schematic diagram of the structure at B in the figure.

[0036] Description of the numbers in the figure:

[0037] 1 bottom plate, 2 primary winding, 3 outer shell, 4 secondary winding, 5 potting layer, 6 magnetic core, 7 connecting layer, 71 lower connecting layer, 72 upper flat layer, 8 pre-broken spherical shell, 9 positioning protrusion, 10 crack-assisting groove, 11 correction and repair layer. DETAILED DESCRIPTION

[0038] The following will combine the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all the embodiments. All other embodiments obtained by ordinary technicians in this field without creative work based on the embodiments of the present invention belong to the scope of protection of the present invention.

[0039] In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "top / bottom" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0040] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "mounted / connected", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0041] Embodiment 1:

[0042] See also Figure 1 A mutual inductor comprises a bottom plate 1, a shell 3 is provided at the upper end of the bottom plate 1, a magnetic core 6 is provided in the shell 3, the magnetic core 6 adopts a ring-shaped ultra-microcrystalline magnetic core, and the secondary winding 4 is formed by automatic winding by a winding machine, the outer end of the magnetic core 6 is wound with the secondary winding 4, a potting layer 5 is poured between the inner wall of the shell 3 and the secondary winding 4, two mutually symmetrical primary windings 2 are provided on the bottom plate 1, the primary winding 2 passes through the inner circle of the magnetic core 6, the primary winding 2 adopts a single-strand copper wire, the copper wire passes through the inner circle of the magnetic core 6, and the lead pin of the primary winding 2 passes through the bottom plate 1, a connecting layer 7 is provided between the primary winding 2, the shell 3 and the bottom plate 1, and the primary winding 2, the secondary winding 4 and the bottom plate 1 are fixed into an integrated structure through the connecting layer 7.

[0043] See also Figure 2The surfaces of the primary winding 2 and the secondary winding 4 are provided with a correction repair layer 11, and the two correction repair layers 11 are respectively located at the position where the primary winding 2 contacts the connection layer 7 and the position where the secondary winding 4 contacts the potting layer 5. The thickness of the correction repair layer 11 is 0.5-1mm. If the correction repair layer 11 is too thick, it is easy to affect the combination of the connection layer 7 and the primary winding 2 and the potting layer 5 and the secondary winding 4, resulting in a decrease in the degree of combination, making the primary winding 2 and the potting layer 5 easy to loosen, leading to The stability of the transformer is reduced. The correction repair layer 11 is too thin, and its filling effect on the gap between the connection layer 7 and the primary winding 2 and the gap between the potting layer 5 and the secondary winding 4 is not obvious. In addition, the lower end surface of the correction repair layer 11 on the primary winding 2 extends to the inside of the bottom plate 1. When the temperature rises to soften the correction repair layer 11, the amount of the softened correction repair layer 11 can be effectively guaranteed to prevent the influence of the change of the correction repair layer 11 due to the state change, and ensure that the connection layer 7 before and after the state change There will be no gaps between the primary winding 2 and between the potting layer 5 and the secondary winding 4, thereby reducing the discharge phenomenon caused by the gaps and improving safety. The correction repair layer 11 is made of thermoplastic plastic, for example, low-density high-pressure polyethylene plastic can be used, and its melting point is 110-115°C. When the potting layer 5 and the connecting layer 7 are poured, the correction repair layer 11 can be melted within this temperature range without affecting the performance of the potting layer 5 and the connecting layer 7 (epoxy resin can work normally at a temperature of -50°C to 180°C), so as to adapt to the shape of the contact surface between the connecting layer 7 and the potting layer 5 and the primary winding 2 and the secondary winding 4, and deform, thereby effectively eliminating the tiny gaps and bubbles on the contact surface, thereby improving the connectivity of the contact surface, thereby effectively controlling the discharge phenomenon caused by tiny gaps and bubbles, on the one hand improving safety, and on the other hand improving the quality of the current transformer, reducing defective products, and thus significantly improving the service life of the current transformer.

[0044] See also Figure 3 The connecting layer 7 includes a lower connecting layer 71 and an upper flat layer 72. The upper flat layer 72, the lower connecting layer 71 and the bottom plate 1 are connected in sequence from top to bottom. The upper flat layer 72 can effectively cover the surface of the lower connecting layer 71. On the one hand, it effectively protects the lower connecting layer 71, making it less likely to crack on its surface, reducing the probability of discharge and improving safety. On the other hand, even if cracks occur on the surface of the lower connecting layer 71, under the limiting effect of the upper flat layer 72, the cracks on the surface of the lower connecting layer 71 can be effectively suppressed from continuing to increase, thereby effectively controlling the degree of discharge and improving the service life of the transformer. Multiple inner filling ball particles are randomly distributed inside the lower connecting layer 71 and the potting layer 5. The lower connecting layer 71 and the potting layer 5 are both made of epoxy resin glue material. The epoxy resin can achieve the effect of insulation and improve safety, while connecting the primary winding 2 and the secondary winding 4 into one.

[0045] See also Figure 4 The inner-filling ball particles include a pre-broken ball shell 8 and a plurality of evenly distributed positioning protrusions 9. The plurality of positioning protrusions 9 are fixedly connected to the outer side of the pre-broken ball shell 8. The inner end of the pre-broken ball shell 8 is filled with self-repairing glue. When cracks appear on the surface of the lower connecting layer 71, the cracks have a force that expands outward, thereby exerting a certain pulling force on the inner-filling ball particles, causing the inner-filling ball particles near the cracks to rupture, and the self-repairing glue inside the particles will flow out and fill the cracks, thereby achieving the effect of effectively controlling the surface cracks of the connecting layer 7.

[0046] See also Figure 5 The surface of the pre-broken spherical shell 8 is preset with a plurality of uniformly distributed crack-promoting grooves 10, and every two crack-promoting grooves 10 are alternately distributed with the positioning protrusions 9. When cracks occur on the surface of the connecting layer 7, the pre-broken spherical shell 8 near the cracks is subjected to the pulling force from the cracks, and the crack-promoting grooves 10 close to the crack side are preferentially cracked. When the cracks extend to the inner filling ball particles, the self-repairing glue will flow to the cracks and patch the cracks, which can suppress the cracks from continuing to grow on the one hand, and effectively eliminate the cracks on the surface of the lower connecting layer 71 on the other hand. The pre-broken spherical shell 8 and the positioning protrusions 9 are made of the same material as the connecting layer 7 and the potting layer 5, and the thickness of the pre-broken spherical shell 8 is 1-2mm. The same material can effectively improve the bonding degree between the inner filling ball particles and the connecting layer 7 and the potting layer 5 during pouring, so that it is difficult to generate bubbles on the contact surface between the inner filling ball particles and the two, thereby ensuring the quality of the connecting layer 7 and the potting layer 5, so that it is not easy to crack due to bubbles during later use.

[0047] The copper wire of the primary winding 2 passes through the inner ring of the magnetic core, and then the primary winding 2 and the secondary winding 4 are connected into an integrated structure through the potting layer 5 and the connecting layer 7, which makes the plug-in simple and can effectively reduce the volume of the current transformer, thereby reducing the production cost. At the same time, the internal filling ball particles can effectively fill the cracks on the surface of the connecting layer 7 and the potting layer 5 using epoxy resin, thereby achieving the effect of filling and effectively inhibiting the continued increase of the cracks. Through the correction repair layer 11, after the current transformer is connected as a whole, the correction repair layer 11 can be melted by temperature changes without affecting the performance of the potting layer 5 and the connecting layer 7, thereby deforming to adapt to the shape of the contact surface, effectively eliminating the tiny gaps and bubbles on the contact surface, and then improving the connection of the contact surface, thereby effectively controlling the discharge phenomenon caused by tiny gaps and bubbles, on the one hand improving safety, on the other hand improving the quality of the current transformer, reducing defective products, and thus significantly improving the service life of the current transformer.

[0048] The above 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 within the technical scope disclosed by the present invention; any equivalent replacement or change based on the technical solution and improved concept of the present invention shall be covered by the protection scope of the present invention.

Claims

1. A mutual inductor, comprising a base plate (1), characterized in that: The upper end of the base plate (1) is provided with a shell (3), a magnetic core (6) is provided in the shell (3), a secondary winding (4) is wound around the outer end of the magnetic core (6), a potting layer (5) is poured between the inner wall of the shell (3) and the secondary winding (4), two mutually symmetrical primary windings (2) are provided on the base plate (1), the primary windings (2) pass through the inner circle of the magnetic core (6), and the lead pins of the primary windings (2) pass through the base plate (1), and the primary windings ( 2), a connecting layer (7) is provided between the housing (3) and the bottom plate (1), the primary winding (2), the secondary winding (4) and the bottom plate (1) are fixed into an integrated structure through the connecting layer (7), and the surfaces of the primary winding (2) and the secondary winding (4) are provided with a corrective repair layer (11), and the two corrective repair layers (11) are respectively located at a position where the primary winding (2) contacts the connecting layer (7) and a position where the secondary winding (4) contacts the potting layer (5); The primary winding (2) is made of a single copper wire, and the copper wire passes through the inner circle of the magnetic core (6); The connecting layer (7) comprises a lower connecting layer (71) and an upper leveling layer (72), and the upper leveling layer (72), the lower connecting layer (71) and the bottom plate (1) are connected in sequence from top to bottom; A plurality of inner ball-replenishing particles are randomly distributed inside the lower connecting layer (71) and the potting layer (5), and the inner ball-replenishing particles include a pre-broken ball shell (8) and a plurality of evenly distributed positioning protrusions (9), the plurality of positioning protrusions (9) are fixedly connected to the outer side of the pre-broken ball shell (8), and the inner end of the pre-broken ball shell (8) is filled with self-repairing glue; The surface of the pre-breaking spherical shell (8) is preset with a plurality of evenly distributed fracture-assisting grooves (10), and every two of the fracture-assisting grooves (10) are alternately distributed with the positioning protrusions (9).

2. A mutual inductor according to claim 1, characterized in that: The magnetic core (6) is a ring-shaped ultra-microcrystalline magnetic core, and the secondary winding (4) is formed by automatic winding using a winding machine.

3. A mutual inductor according to claim 1, characterized in that: The lower connecting layer (71) and the potting layer (5) are both formed by pouring epoxy resin adhesive material.

4. A mutual inductor according to claim 1, characterized in that: The pre-cut spherical shell (8) and the positioning protrusion (9) are made of the same material as the connecting layer (7) and the potting layer (5), and the thickness of the pre-cut spherical shell (8) is 1-2 mm.

5. A mutual inductor according to claim 1, characterized in that: The correction repair layer (11) has a thickness of 0.5-1 mm, and the lower end surface of the correction repair layer (11) on the primary winding (2) extends to the inside of the bottom plate (1).

6. A mutual inductor according to claim 1, characterized in that: The correction and repair layer (11) is made of thermoplastic plastic.

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