A filter inductor with insulation function

Abstract

The application relates to the technical field of inductors, in particular to a filtering inductor with an insulation function, which is suitable for intelligent inductor manufacturing, and is characterized in that independent winding coils are respectively wound on first and second magnetic cores, insulation end plates are symmetrically installed on the two axial ends, metal connecting rows are installed on the insulation end plates, and winding leads are welded with the metal connecting rows. The filtering inductor further comprises an insulation middle-seam partition plate, which is arranged in the gap between the two magnetic cores, and the two ends of the insulation middle-seam partition plate are provided with buckles, a first matching groove is formed in the insulation end plate, the groove bottom extends inward to form a second matching groove, and the buckles are buckled in the double grooves. The pure insulation middle-seam partition plate blocks the linear creeping path of the two groups of windings and the connecting rows; the partition plate is provided with staggered and arranged increased-creeping convex ribs on the two sides, so that the surface discharge channel is forced to be S-shaped or Z-shaped and detours, the creeping distance is increased by several times compared with the plane structure, and under the typical high-humidity, salt fog, dust and high-harmonic working conditions of the smart grid industry, the surface discharge and flying arc are effectively inhibited, and long-term insulation safety is ensured.

Description

Technical Field

[0001] This invention relates to the field of inductor technology, specifically to a filter inductor with insulation function. Background Technology

[0002] A filter is a filtering circuit composed of capacitors, inductors, and resistors. A filter can effectively filter out a specific frequency point or frequencies other than that frequency point in a power line to obtain a power signal of a specific frequency, or eliminate a power signal after a specific frequency.

[0003] In smart grids, static var generators (SVG), energy storage converters (PCS), DC charging piles, and distribution network harmonic mitigation equipment generally adopt dual-channel or multi-phase interleaved parallel filtering schemes.

[0004] Currently, most dual-channel or multi-phase interleaved parallel filtering solutions on the market adopt simple assembly. The gap between the two magnetic cores usually relies only on air insulation or simple flat plate isolation, without setting up a dedicated insulation barrier structure. This assembly method relies on manual alignment in the manufacturing of intelligent inductors, making it difficult to achieve automated assembly and insulation consistency control.

[0005] In the outdoor high humidity, salt spray, dust and high frequency harmonic conditions common in the smart grid industry, surface creep discharge is very likely to occur between the winding surfaces and lead terminals of the two magnetic cores; at the same time, the lack of effective physical isolation between the two magnetic circuits can cause leakage magnetic coupling to cause inductance drift and affect filtering accuracy. Summary of the Invention

[0006] The purpose of this invention is to provide a filter inductor with insulation function to solve the problems in the prior art where surface creep discharge easily occurs between the winding surfaces and lead terminals of the two magnetic cores under outdoor high humidity, salt spray, dust and high frequency harmonic conditions commonly encountered in the smart grid industry; at the same time, the lack of effective physical isolation between the two magnetic circuits leads to leakage magnetic coupling, which causes inductance drift and affects filtering accuracy.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] An insulating filter inductor includes a first magnetic core and a second magnetic core, each with an independent winding coil wound on it. Insulating end plates are symmetrically mounted at both axial ends of the first and second magnetic cores, and metal connecting bars are mounted on the insulating end plates. Leads at both ends of the winding coils are welded to the metal connecting bars at both ends. The inductor also includes an insulating center gap partition disposed in the gap between the first and second magnetic cores. Both ends of the insulating center gap partition are provided with snap-fit ​​fasteners. A first mating groove is correspondingly formed on the insulating end plate, and the bottom of the first mating groove extends inward into the insulating end plate to form a second mating groove. The snap-fit ​​fasteners engage with the first and second mating grooves.

[0009] Preferably, the insulating center seam partition has a dielectric encapsulation cavity inside, which is filled with a thermally conductive material. The insulating center seam partition has creepage ribs on two opposite sides facing the first and second magnetic cores, and the creepage ribs are arranged alternately. The other two outer side walls of the insulating center seam partition have structural reinforcing ribs.

[0010] Preferably, it also includes a sealing and insulating adhesive, which fills the first mating groove and the second mating groove and covers the fastening part of the buckle.

[0011] Preferably, the insulating end plate has a third mating groove, the third mating groove includes an embedded part and a first overlapping part, the metal connecting bar includes a main body installed in the embedded part, the main body is provided with a first bending part, and the first bending part overlaps in the first overlapping part on the third mating groove.

[0012] Preferably, the metal connecting strip further includes a second bent portion, the embedded portion of the third mating groove extends out of the side of the insulating end plate to form a second overlapping portion, the wall of the second overlapping portion extends into the insulating end plate to form a first slot, a first pin is provided on the second bent portion, a second slot is provided on the third mating groove, a second pin is provided on the main body, the first pin is inserted into the first slot, and after bending, the main body is fastened so that the second pin is inserted into the second slot; wherein, the metal connecting strip and the third mating groove are filled with sealing insulating glue.

[0013] Preferably, it also includes an insulating seat, which is disposed on one side of the first magnetic core and the second magnetic core. An air gap is left between the insulating seat and the first magnetic core and the second magnetic core. A strip groove is formed on the side of the insulating seat facing the insulating center seam partition. The structural reinforcing ribs of the insulating center seam partition are embedded in the strip groove and form a lateral limiting fit.

[0014] Preferably, a fourth mating groove is provided at both ends of the insulating base, and a mating foot extends from the insulating end plate. The mating foot is inserted into the fourth mating groove. The fourth mating groove is filled with sealing insulating glue, which covers the insertion part of the mating foot and is flush with the outer surface of the insulating base.

[0015] Preferably, it further includes an insulating housing, on which two opposite sidewalls are provided with perforations, through which the pins of the metal connecting bar pass. An insulating sleeve is fitted on the inner wall of the perforation, covering the outer periphery of the pins. Annular creepage ribs are provided on the inner sidewall of the housing around the perforation, arranged around the perforation to increase the surface creepage distance between the pins and the live parts outside the housing. The gap between the pins and the perforation is filled with sealing insulating adhesive.

[0016] Compared with the prior art, the beneficial effects of the present invention are:

[0017] 1. By setting an insulating gap partition between the first and second magnetic cores, the straight creepage path between the two independent windings and the metal connecting bar is physically blocked. The partition has staggered creepage-enhancing ribs on the opposite sides facing the two magnetic cores, which forces the surface discharge channel to be S-shaped or Z-shaped and the creepage distance is increased several times compared with the planar structure. Under the typical high humidity, salt spray, dust and high harmonic conditions of the smart grid industry, it effectively suppresses surface discharge and arcing, and ensures the long-term insulation safety of the dual-channel filter inductor.

[0018] 2. The two ends of the insulating center seam partition are fastened to the first and second mating grooves of the insulating end plate by snap-fit, forming a two-stage purely mechanical locking. Assembly does not require metal screws, avoiding the problems of eddy current loss and damage to insulation continuity introduced by metal parts. The reinforcing ribs of the partition are embedded in the strip groove of the insulating seat to form lateral limiting. The mating feet of the end plate are inserted into the fourth mating groove of the insulating seat to form end constraint. The metal connecting bar is fixed in the third mating groove by multiple pins and bends. Each component forms omnidirectional constraint in the axial, lateral and bottom directions, reducing the occurrence of loosening or displacement under the long-term electromagnetic vibration of smart grid equipment. This meets the industrial upgrading needs of smart inductor manufacturing for automated press-fitting, visual alignment and maintenance-free reliability.

[0019] 3. The dielectric encapsulation cavity inside the insulating seam partition is filled with phase change material. When the switch generates heat due to harmonic peaks, it absorbs heat through a solid-liquid phase change and releases it slowly, with no liquid flow, evaporation, or condensation throughout the process, reducing the risk of liquid cooling leakage. The first, second, and fourth mating grooves, as well as the gaps in the outer casing perforations, are layered with sealing insulating adhesive, covering the snap-fit ​​parts, mating foot insertion parts, and the outer periphery of the pins. The insulating sleeve and adhesive layer cure flush, forming a fully enclosed moisture-proof seal from the internal seam to the external terminal. This structure provides durable insulation margin in outdoor cabinets in the smart grid industry and in coastal high-salt-spray environments, extending product lifespan. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0021] Figure 2 This is a schematic diagram of the internal structure of the insulating shell of the present invention;

[0022] Figure 3 This is a schematic diagram of the main structure of the filter inductor of the present invention;

[0023] Figure 4 This is a schematic diagram of the filter inductor structure of the present invention without winding coils;

[0024] Figure 5 This is a schematic diagram of the winding coil and metal connection bar structure of the present invention;

[0025] Figure 6 This is a schematic diagram of the insulating end plate structure of the present invention;

[0026] Figure 7 This is a schematic diagram of the insulating center-slit partition structure of the present invention;

[0027] Figure 8 for Figure 3 Enlarged view of the A-structure;

[0028] Figure 9 This is a schematic diagram of the sealing and insulating adhesive of the present invention covering the insulating end plate.

[0029] In the attached diagram, the components represented by each number are as follows:

[0030] 10. First magnetic core;

[0031] 20. Second magnetic core;

[0032] 30. Winding coil; 31. Lead wire;

[0033] 40. Insulating end plate; 41. First mating groove; 42. Second mating groove; 43. Third mating groove; 431. Embedded part; 432. First overlapping part; 433. Second overlapping part; 434. First slot; 435. Second slot; 44. Mating foot;

[0034] 50. Metal connector; 51. Main body; 511. Second pin; 52. First bend; 53. Second bend; 531. First pin; 54. Lead;

[0035] 60. Insulating center seam partition; 61. Clip; 62. Dielectric encapsulation cavity; 63. Creep-up reinforcement rib; 64. Structural reinforcing rib;

[0036] 70. Sealing and insulating adhesive;

[0037] 80. Insulating base; 81. Strip groove; 82. Fourth mating groove;

[0038] 90. Insulating outer shell; 91. Perforation; 92. Insulating sleeve; 93. Annular creepage rib. Detailed Implementation

[0039] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0040] Example 1: As Figure 1 - Figure 9 As shown, a filter inductor with insulation function is mainly used in power electronic scenarios requiring dual-channel filtering, such as distribution automation, energy storage converters, and charging piles in the smart grid industry.

[0041] Specifically, it includes a first magnetic core 10 and a second magnetic core 20. The two sets of magnetic cores are arranged side by side in the same mounting plane, and their magnetic circuits are independent of each other. Leakage magnetic coupling is effectively suppressed through spatial spacing and insulating partitions. Independent winding coils 30 are wound on the first magnetic core 10 and the second magnetic core 20, respectively. The number of turns and wire diameter of the two sets of winding coils 30 can be independently set according to actual filtering requirements, and there is no electrical connection or magnetic circuit coupling between them.

[0042] Insulating end plates 40, made of flame-retardant insulating engineering plastic, are symmetrically mounted on both ends of the first magnetic core 10 and the second magnetic core 20. They are fixed to the axial end faces of the two magnetic cores by adhesive bonding, serving as support, positioning, and electrical isolation. Metal connecting bars 50, made of conductive copper, are mounted on the insulating end plates 40, serving as interfaces for external electrical connections. The leads 31 at both ends of the winding coil 30 are welded to the metal connecting bars 50 at both ends to form a stable current path.

[0043] It is worth noting that two sets of metal connecting bars 50 are installed on the insulating end plate 40, corresponding to the leads 31 of the two windings respectively.

[0044] It also includes an insulating center gap partition 60, which is disposed in the gap between the first magnetic core 10 and the second magnetic core 20 to physically block the creepage path between the first magnetic core 10, the second magnetic core 20 and the winding coil 30, and prevent surface discharge under high humidity and high harmonic conditions.

[0045] Both ends of the insulating center-seam partition 60 are provided with snap fasteners 61, and the insulating end plate 40 has a corresponding first mating groove 41. The bottom of the first mating groove 41 extends into the insulating end plate 40 to form a second mating groove 42. During assembly, the snap fasteners 61 at both ends of the insulating center-seam partition 60 are first inserted into the first mating groove 41, and then slide axially to further engage the snap fasteners 61 into the second mating groove 42. The elasticity of the snap fasteners 61 itself forms a two-stage locking mechanism. The structure of the snap fasteners 61 engaging in the first and second mating grooves 41 and 42 allows the insulating center-seam partition 60 to be installed without metal screws or adhesive. It can be quickly installed by hand and reliably positioned solely by the elastic deformation of the insulating material.

[0046] In the manufacturing process of intelligent inductors, the above-mentioned buckle 61 is adapted to the automated production line with the double-slot structure: the insulating end plate 40 and the insulating middle seam partition 60 can be automatically fed by the vibratory feeder, the alignment of the buckle 61 with the first mating slot 41 and the second mating slot 42 is completed by the servo press-fitting station, and the assembly accuracy is checked by the vision imaging system to ensure that the buckle 61 is fully inserted into the slot and the partition is centered without deviation;

[0047] The welding process can be completed by using laser welding equipment to connect the lead 31 to the metal connector 50. The quality of the weld is inspected by AOI. The finished product can be tested for inter-turn withstand voltage and insulation resistance before leaving the factory.

[0048] As a preferred mode of operation of the present invention, in a typical application of the smart grid industry, the winding coil 30 on the first magnetic core 10 and the winding coil 30 on the second magnetic core 20 are connected in an interleaved parallel topology, that is, the phase difference of the two-phase switch drive signals is 180°, so that the direction of the high-frequency ripple current is opposite.

[0049] Specifically, when this filter inductor is applied to the output filtering of an energy storage converter or the multi-phase parallel filtering of a high-power charging pile, the two winding coils 30 are respectively connected to two-phase staggered switch arms. Since the magnetic circuits of the first magnetic core 10 and the second magnetic core 20 are relatively independent, the inductance of one set of windings will not decrease or saturate due to the current change of the other set of windings. At the same time, the high-frequency ripple currents in opposite directions partially cancel each other out at the input or output terminals, effectively reducing the input current ripple amplitude of the overall filter and reducing harmonic pollution to the front-end power grid.

[0050] In this preferred embodiment, when a reverse high-frequency large current is applied to the two winding coils 30, the winding leads 31 and the metal connecting bar 50 are subjected to a high voltage change rate and potential difference. The insulating center gap partition 60 physically blocks the shortest creepage path between the two sets of charged bodies, preventing surface discharge or arcing in high humidity and salt spray environments. The two-stage locking structure of the buckle 61 and the first mating groove 41 and the second mating groove 42 ensures that the partition does not shift or loosen under long-term electromagnetic vibration and alternating stress generated by reverse current, maintaining a stable insulation gap.

[0051] Reference Figure 7 The insulating center-seam partition 60 has a dielectric encapsulation cavity 62 inside. The dielectric encapsulation cavity 62 is a closed cavity structure located in the geometric center region of the partition body. The cavity wall thickness is designed according to the insulation withstand voltage level. The dielectric encapsulation cavity 62 is filled with a thermally conductive material. The thermally conductive material is preferably a non-flowing phase change composite insulating thermally conductive gel or a microcapsule phase change material. Under typical operating conditions in the smart grid industry, it remains in a solid or gel state, without evaporation or circulation, and has both electrical isolation and heat conduction functions.

[0052] The insulating center-slit partition 60 has creepage-enhancing ribs 63 on its two opposite sides facing the first magnetic core 10 and the second magnetic core 20. These creepage-enhancing ribs 63 are strip-shaped, tooth-shaped, or wavy structures protruding outwards along the side surface. Their height and pitch are determined according to the rated insulation voltage and pollution level of the smart grid equipment. The creepage-enhancing ribs 63 on both sides are staggered, meaning the ribs facing the first magnetic core 10 and the ribs facing the second magnetic core 20 are offset from each other in their axial projection and are not in the same vertical plane. This staggered arrangement changes the surface creepage path between the two sets of winding coils 30 and the metal connecting bar 50 from a straight line to multiple broken lines, significantly increasing the creepage distance.

[0053] The other two outer side walls of the insulating center seam partition 60 are provided with structural reinforcing ribs 64. The structural reinforcing ribs 64 are rib-shaped protrusions extending laterally along the surface of the outer side wall, which are used to improve the overall bending strength and deformation resistance of the insulating center seam partition 60 and prevent bending and cracking under assembly or long-term electromagnetic vibration.

[0054] The first magnetic core 10 and the second magnetic core 20 generate periodic core losses and winding copper losses under high-frequency switching conditions. Heat accumulates in the middle gap region. The dielectric encapsulation cavity 62 inside the insulating middle gap partition 60 is filled with a thermally conductive material. This material has a thermal transfer coefficient higher than that of air. When the temperature of the magnetic cores on both sides of the insulating middle gap partition 60 rises, the thermally conductive material in the dielectric encapsulation cavity 62 conducts heat to the partition body for dissipation through a thermal transfer coefficient higher than that of air. Among them, the phase change material can further suppress the peak temperature rise through latent heat absorption when the phase change temperature is reached, and then slowly dissipates to the external environment through the partition body.

[0055] Filter inductors often operate in high-humidity, salt spray, and dusty environments, making surface insulation between the two sets of charged components crucial for safety. The staggered creepage ribs 63 on both sides of the insulating center-slit partition 60 physically lengthen the surface creepage path between the windings of the first magnetic core 10 and the second magnetic core 20. The staggered design ensures that the shaded area of ​​one rib corresponds precisely to the raised area of ​​the other rib, forcing the creepage path to be S-shaped or Z-shaped, significantly increasing the creepage distance compared to a flat partition and suppressing damp-heat surface discharge and arcing.

[0056] Example 2:

[0057] like Figures 1 to 9 As shown, in this second embodiment, based on the first embodiment, a sealing insulating adhesive 70 is further added to enhance the connection reliability and environmental protection capability between the insulating middle seam partition 60 and the insulating end plate 40.

[0058] Specifically, the sealing and insulating adhesive 70 is filled into the first mating groove 41 and the second mating groove 42 on the insulating end plate 40 and covers the fastening part of the buckle 61. The sealing and insulating adhesive 70 is injected into the cavity of the first mating groove 41 and the second mating groove 42 in a liquid or semi-fluid state, and then undergoes a curing reaction to form an elastic solid seal.

[0059] The cured sealant 70 completely fills the gap between the first mating groove 41 and the second mating groove 42, and covers the snap-fit ​​part of the buckle 61. This ensures that the mechanical locking interface between the buckle 61 and the first mating groove 41 and the second mating groove 42 is completely covered and fixed by the adhesive layer. This is equivalent to adding an extra solid insulating layer on the mechanical locking interface. Its dielectric strength is much higher than that of air, which further increases the insulation distance between the two sets of charged bodies, improves the overall insulation margin, and seals the gaps, preventing external moisture, corrosive gases and conductive dust from entering the mating interface, and maintaining the dryness and cleanliness of the internal insulation environment.

[0060] Example 3:

[0061] like Figures 3 to 8As shown, this embodiment three further refines the assembly and fixing structure between the metal connecting strip 50 and the insulating end plate 40 based on embodiments one and two.

[0062] Specifically, the insulating end plate 40 is provided with a third mating groove 43. The third mating groove 43 is a cavity on the insulating end plate 40 for accommodating and positioning the metal connecting strip 50. It includes an insert portion 431 and a first overlapping portion 432. The insert portion 431 is the main recessed part of the cavity. The first overlapping portion 432 is a step extending outward from the edge of the insert portion 431. The metal connecting strip 50 includes a main body 51 installed in the insert portion 431. The main body 51 is provided with a first bending portion 52. The first bending portion 52 is formed by bending the edge of the main body 51. During assembly, the first bending portion 52 overlaps in the first overlapping portion 432 on the third mating groove 43, forming the initial positioning and axial constraint of the metal connecting strip 50.

[0063] Furthermore, the metal connecting strip 50 also includes a second bent portion 53, the insert portion 431 of the third mating groove 43 extends out of the side of the insulating end plate 40 to form a second overlapping portion 433, the wall of the second overlapping portion 433 extends into the insulating end plate 40 to form a first slot 434, a first pin 531 is provided on the second bent portion 53, a second slot 435 is provided on the third mating groove 43, a second pin 511 is provided on the main body 51, the first pin 531 is inserted into the first slot 434, and after bending, the main body 51 is fastened so that the second pin 511 is inserted into the second slot 435.

[0064] During assembly, the first pin 531 on the second bent portion 53 is inserted into the first slot 434 on the wall of the second overlapping portion 433. A bending force is applied to the second bent portion 53, causing it to bend towards the main body 51 and fasten onto the main body 51. This bending action simultaneously pushes or presses the main body 51, causing the second pin 511 on the main body 51 to smoothly insert into the second slot 435 on the third mating groove 43, forming a double insertion and locking mechanism.

[0065] After assembly, the gap between the metal connecting strip 50 and the third mating groove 43 is filled with sealing insulating adhesive 70. The sealing insulating adhesive 70 is preferably epoxy resin, silicone or polyurethane adhesive. After filling, it covers the mating interface of the first pin 531, the second pin 511 and the corresponding slot, as well as the overlapping interface of the first bend 52 and the first overlap 432, forming a continuous solid insulating barrier around the connecting strip, blocking the entry path of moisture and conductive dust. At the same time, after the adhesive layer cures, it bonds the metal connecting strip 50 and the insulating end plate 40 together, eliminating friction and wear caused by micro-vibration and improving the durability of the overall structure.

[0066] Example 4:

[0067] Reference Figure 3 , Figure 4 and Figure 8 In this embodiment, an insulating base 80 structure for overall support and positioning is further added based on the previous embodiment.

[0068] Specifically, the insulating base 80 is disposed on one side of the first magnetic core 10 and the second magnetic core 20. In this embodiment, the insulating base 80 is disposed at the bottom of the first magnetic core 10 and the second magnetic core 20, such as... Figure 3 As shown. The insulating base 80 is integrally molded from flame-retardant insulating engineering plastic to assist in heat dissipation from the sides of the first magnetic core 10 and the second magnetic core 20. An air gap is left between the insulating base 80 and the first magnetic core 10 and the second magnetic core 20. A strip groove 81 is opened on the side of the insulating base 80 facing the insulating center seam partition 60. During assembly, the structural reinforcing rib 64 of the insulating center seam partition 60 is embedded in the strip groove 81 and forms a lateral limiting fit. That is, the insulating center seam partition 60 is constrained by the strip groove 81 in the horizontal direction perpendicular to the magnetic core axis and cannot sway left and right.

[0069] Furthermore, both ends of the insulating base 80 are provided with a fourth mating groove 82. Correspondingly, a mating foot 44 extends from the insulating end plate 40. During assembly, the mating foot 44 is inserted into the fourth mating groove 82, so that the insulating end plate 40 and the insulating base 80 are connected at the end, and the end plate is constrained to flip outward.

[0070] The fourth mating groove 82 is filled with sealing insulating adhesive 70. The sealing insulating adhesive 70 covers the insertion part of the mating foot 44 and is flush with the outer surface of the insulating base 80, blocking the path of moisture and conductive particles to enter the internal charged area along the mating gap; at the same time, the adhesive force of the adhesive layer sticks the mating foot 44 to the fourth mating groove 82 together, preventing the mating foot 44 from loosening due to transportation vibration or thermal expansion and contraction, and achieving long-term insulation reliability under maintenance-free conditions.

[0071] Example 5:

[0072] Reference Figure 1 and Figure 2 In this embodiment, an insulating outer shell 90 structure for overall external protection is further added based on the previous embodiment.

[0073] Specifically, the insulating housing 90 consists of a box-shaped housing with an opening at the top and a cover plate. The cover plate is sealed inside the opening of the housing with sealant, and the internal components such as the first magnetic core 10, the second magnetic core 20, the insulating end plate 40, the winding coil 30 and the metal connecting bar 50 are completely covered inside and filled with glue, with only the external wiring interface reserved.

[0074] The insulating housing 90 has perforations 91 on two opposite sidewalls. The pins 54 of the metal connecting bar 50 pass through the perforations 91. An insulating sleeve 92 is fitted on the inner wall of the perforation 91. The insulating sleeve 92 is a pre-formed flexible insulating tube. The insulating sleeve 92 is pre-fitted around the pins 54. After the insulating sleeve 92 passes through the perforation 91 along with the pins 54, its outer wall is tightly attached to the hole wall of the perforation 91 and further covers the outer periphery of the pins 54, forming a continuous solid insulating barrier between the pins 54 and the housing of the insulating housing 90.

[0075] Annular creepage ribs 93 are provided on the inner sidewall of the housing surrounding the perforation 91. The annular creepage ribs 93 are annular raised ribs arranged concentrically along the outer periphery of the perforation 91, and their height and number of rings are determined according to the rated insulation voltage and pollution level of the smart grid equipment. The annular creepage ribs 93 are arranged around the perforation 91, so that the surface creepage path between the pin 54 and the outside of the insulating housing 90 is changed from a straight distance to a multi-fold line distance along the surface of the annular creepage ribs 93, which significantly increases the creepage length.

[0076] The gap between pin 54 and through hole 91 is filled with sealing insulating glue 70.

[0077] After the pins 54 of the metal connector 50 pass through the perforations 91 of the insulating housing 90, they are exposed to the external environment. If the pins 54 are in direct contact with the wall of the perforation 91, metal corrosion or creepage short circuits are likely to occur along the wall of the perforation in the high humidity and salt spray environment of the smart grid industry. The insulating sleeve 92 is fitted on the inner wall of the perforation 91 and covers the outer periphery of the pins 54, establishing an independent solid insulating layer between the pins 54 and the housing, with a dielectric strength much higher than that of air. Even if there is condensation or conductive dust in the external environment, the sleeve can effectively block the electrical path between the pins 54 and the housing, ensuring the insulation safety of the external terminals.

[0078] In the smart grid industry, filter inductors are often deployed in outdoor transformer substations, inside charging piles, or in high-altitude coastal areas. These scenarios have stringent safety requirements for electrical clearances and creepage distances. The annular creepage ribs 93 are arranged concentrically around the perforation 91. Within the limited shell wall thickness, the surface creepage path between the pin 54 and the live parts outside the shell is forced from a straight distance to a multi-folded distance along the surface of the annular ribs. Each ring of the annular creepage ribs 93 is equivalent to adding a creepage length. After multiple rings are superimposed, the total creepage distance can be increased several times, effectively preventing surface discharge and arcing along the outer wall of the shell in high humidity and high pollution environments.

[0079] An unavoidable assembly gap exists between pin 54 and through hole 91. If this gap is not sealed, it will become a channel for moisture, salt spray, and conductive dust to enter the interior of the housing. After the sealing insulating adhesive 70 fills the gap and cures, it forms an airtight annular sealing ring between pin 54 and through hole 91, blocking the intrusion path of external contaminants into the internal charged area. At the same time, the adhesive layer has a certain elastic or rigid bonding effect, which can absorb the torsional or tensile stress applied to pin 54 during external wiring, prevent stress from being transmitted to the internal solder joint and causing breakage, and improve the mechanical reliability of the overall structure.

[0080] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus.

[0081] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A filter inductor with insulation function, characterized in that, The system includes a first magnetic core (10) and a second magnetic core (20). Independent winding coils (30) are wound on the first magnetic core (10) and the second magnetic core (20). Insulating end plates (40) are symmetrically installed at both ends of the first magnetic core (10) and the second magnetic core (20). Metal connecting bars (50) are installed on the insulating end plates (40). The leads (31) at both ends of the winding coils (30) are welded to the metal connecting bars (50) at both ends. It also includes an insulating center seam partition (60), which is disposed in the gap between the first magnetic core (10) and the second magnetic core (20). Both ends of the insulating center seam partition (60) are provided with buckles (61). A first mating groove (41) is correspondingly opened on the insulating end plate (40). The bottom of the first mating groove (41) extends into the insulating end plate (40) to form a second mating groove (42). The buckles (61) are fastened in the first mating groove (41) and the second mating groove (42).

2. A filter inductor with insulation function according to claim 1, characterized in that: The insulating center seam partition (60) has a dielectric encapsulation cavity (62) inside, which is filled with thermally conductive material. The insulating center seam partition (60) has creepage ribs (63) on two opposite sides facing the first magnetic core (10) and the second magnetic core (20). The creepage ribs (63) are arranged in an alternating pattern. The other two outer side walls of the insulating center seam partition (60) are provided with structural reinforcing ribs (64).

3. A filter inductor with insulation function according to claim 1, characterized in that: It also includes a sealing insulating adhesive (70), which fills the first mating groove (41) and the second mating groove (42) and covers the fastening part of the buckle (61).

4. A filter inductor with insulation function according to claim 1, characterized in that: The insulating end plate (40) is provided with a third mating groove (43), the third mating groove (43) includes an embedding part (431) and a first overlapping part (432), the metal connecting bar (50) includes a main body (51) installed in the embedding part (431), the main body (51) is provided with a first bending part (52), the first bending part (52) overlaps in the first overlapping part (432) on the third mating groove (43).

5. A filter inductor with insulation function according to claim 4, characterized in that: The metal connecting bar (50) also includes a second bent portion (53). The embedding portion (431) of the third mating groove (43) extends out of the side of the insulating end plate (40) to form a second overlapping portion (433). The wall of the second overlapping portion (433) extends into the insulating end plate (40) to form a first slot (434). A first pin (531) is provided on the second bent portion (53). A second slot (435) is provided on the third mating groove (43). A second pin (511) is provided on the main body (51). The first pin (531) is inserted into the first slot (434). After bending, the main body (51) is fastened so that the second pin (511) is inserted into the second slot (435). The metal connecting bar (50) and the third mating groove (43) are filled with sealing insulating glue (70).

6. A filter inductor with insulation function according to claim 1, characterized in that: It also includes an insulating seat (80), which is disposed on one side of the first magnetic core (10) and the second magnetic core (20). An air gap is left between the insulating seat (80) and the first magnetic core (10) and the second magnetic core (20). A strip groove (81) is opened on the side of the insulating seat (80) facing the insulating center seam partition (60). The structural reinforcing rib (64) of the insulating center seam partition (60) is embedded in the strip groove (81) and forms a lateral limiting fit.

7. A filter inductor with insulation function according to claim 6, characterized in that: Both ends of the insulating base (80) are provided with a fourth mating groove (82), and a mating foot (44) extends from the insulating end plate (40) and is inserted into the fourth mating groove (82); The fourth mating groove (82) is filled with sealing insulating glue (70), which covers the insertion part of the mating foot (44) and is flush with the outer surface of the insulating seat (80).

8. A filter inductor with insulation function according to claim 1, characterized in that: It also includes an insulating housing (90), on which two opposite sidewalls are provided perforations (91), through which pins (54) of the metal connecting bar (50) pass through the perforations (91), and an insulating sleeve (92) is fitted on the inner wall of the perforations (91), the insulating sleeve (92) covering the outer periphery of the pins (54), and annular creepage ribs (93) are provided on the inner sidewall of the housing around the perforations (91), the annular creepage ribs (93) are arranged around the perforations (91) to increase the surface creepage distance between the pins (54) and the live parts outside the housing; The gap between the pin (54) and the through hole (91) is filled with sealing insulating glue (70).

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