A winding method for preventing short circuit of a transformer with same slot multi-winding outgoing line

Abstract

The application relates to the technical field of electronic transformer manufacturing, in particular to a winding method for preventing short circuit of a transformer with same-slot multi-winding outgoing lines. The method comprises the following steps: arranging a flat and tightly closed partition wall on a transformer framework, winding at least two sets of specified position close-to-partition-wall close-winding windings in a winding window, straightening the end of the close-winding windings, leading out the end to the same line slot, performing positive and negative connection line processing on the outgoing line, and arranging a sleeve across the inside of the partition wall according to the potential difference, and finally completing the layer insulation rubber coating, line arrangement and PIN soldering process. The application can effectively solve the short circuit risk and structural inconsistency problem caused by the potential difference of the multi-winding same-slot outgoing lines, and improve the electrical safety and assembly reliability of the product.

Description

Technical Field

[0001] This application relates to the field of electronic transformer manufacturing technology, and in particular to a method for preventing short circuits by connecting the forward and reverse windings of a transformer with multiple windings in the same slot. Background Technology

[0002] As a core component in power electronic systems, transformers are widely used in power adapters, industrial control, communication equipment and consumer electronics. Their main functions are to realize voltage transformation, current isolation and impedance matching. In the manufacturing process of transformers, the winding process is the key link that determines the electrical performance and safety reliability of the product.

[0003] However, existing technologies still face certain technical challenges in actual production and long-term use. Especially in scenarios where multiple windings need to be drawn from the same slot, the potential difference between windings can easily lead to localized electric field concentration in the confined space of the slot if the outgoing wires are not handled properly, resulting in insulation breakdown or short-circuit faults. Furthermore, in traditional processes, it is often difficult to maintain consistency in the positioning of the winding ends, the control of the lead-out angle, and the fit between the bushing and the retaining wall. This can easily cause problems such as loose coil structure, bushing slippage, or core assembly interference, thus affecting the overall product yield and long-term operational stability. How to effectively manage the electrical safety distance and mechanical structural reliability of multiple windings within a limited space remains a pressing technical challenge in this field. Summary of the Invention

[0004] This application provides a method for short-circuit protection winding of a transformer with multiple windings in the same slot and reverse connection to solve the above-mentioned problems. The method includes: S1. Install retaining walls on the transformer frame, making the retaining walls flat, tight and close to both sides of the frame; S2. At least two sets of multiple windings that need to be led out from the same wire slot are wound in the skeleton winding window. Each winding is arranged according to the corresponding winding area and winding density. Each winding is densely wound at a specified position. The end of each winding is set on the side close to the retaining wall. S3. Pull the end of each winding at a right angle and lead it out into the same wire slot; S4. Perform forward and reverse wiring treatment on multiple winding leads drawn out from the same wire slot, and configure sleeves for some leads according to the potential difference between each lead out in the wire slot. When configuring the sleeves, the sleeves extend into the coil side and pass through the inside of the retaining wall. S5. After completing the remaining interlayer insulation coating and wiring work, connect the outgoing wires to the pins and then perform the soldering process.

[0005] Optionally, when setting up the retaining wall, the gap between the beginning and end of the retaining wall is controlled to be no more than 1mm, and the height of the retaining wall is adapted to the height of the winding to prevent the enameled wire from slipping onto the retaining wall tape.

[0006] Optionally, the at least two sets of windings are wound in the same slot in a time-sharing manner, with one set of windings wound clockwise and the other set of windings wound counterclockwise. Each set of windings is arranged at the bottom, middle or top of the skeleton winding window. When three or more windings need to be led out from the same slot, the winding directions of the multiple windings are alternately configured in a clockwise, counterclockwise, and clockwise manner.

[0007] Optionally, when the multiple sets of windings are two sets of windings, one set of windings is densely wound at a designated position, and the other set of windings is sparsely wound at full layer. The end of both sets of windings is located on the side close to the retaining wall. When there are three or more sets of windings, the windings are arranged alternately in the order of dense winding at a specified position, sparse winding at full layer, and dense winding at a specified position, and the end of all windings is set on the side close to the retaining wall.

[0008] Optionally, when pulling the end of each winding out at a right angle, ensure that the winding wires enter and exit the slots without exceeding the frame radius (R angle) to avoid interference during subsequent core assembly.

[0009] Optionally, the reverse connection process is characterized by performing polarity reversal pairing on different winding leads from the same slot after clockwise and counterclockwise pairing of the winding body. This is to distinguish it from the connection method that simply changes the physical direction of the lead connection pins and does not match the winding polarity of the winding body.

[0010] Optionally, the outlet of the configured sleeve must be flush with the B / N groove opening of the skeleton and reach at least two-thirds of the groove height; The fly wire type lead-out sleeve extends into the B / N bend position of the skeleton to prevent the sleeve from slipping off the lead wire.

[0011] Optionally, the width of the interlayer insulating tape is equal to the width of the skeleton winding. The tape's overlapping edge is positioned on the core assembly side, and the tape end crosses the center of the bobbin winding window to prevent the tape from lifting.

[0012] Optionally, during the wiring operation, the enameled wire must not be crossed over the retaining wall tape, and the bending direction of each winding wire should be controlled so that the multiple outgoing leads in the wire groove are staggered. If the starting and ending ends of the winding are on the same side of the frame, place isolation tape in advance before folding the ending end back and hanging the pin.

[0013] Optionally, when the outgoing wire is connected to the PIN, the number of turns is determined according to the diameter of the enameled wire; For wires with a diameter greater than 0.6mm, wrap at least 0.8 turns; for wires with a diameter equal to 0.6mm, wrap at least 0.8 turns; for wires with a diameter greater than 0.32mm and less than 0.6mm, wrap at least 1.5 turns; for wires with a diameter equal to 0.32mm, wrap at least 2.5 turns; and for wires with a diameter less than 0.32mm, wrap at least 2.5 turns. Ensure the knot is tightly wrapped.

[0014] This application provides a method for short-circuit protection winding of transformers with multiple windings in the same slot, using reverse connection. This method establishes a basic physical isolation barrier and safety distance benchmark by installing flat, tight, and closely spaced retaining walls on both sides of the transformer frame. Based on this, at least two sets of tightly wound windings at designated positions are wound in the frame winding window, with the termination ends uniformly positioned near the retaining wall. This results in a high degree of order and consistency in the spatial distribution of the winding structure. Furthermore, by pulling the termination ends to a right angle and leading them into the same slot, the trajectory and shape of the outgoing lines are standardized. Subsequently, the multiple outgoing lines from the slot are subjected to reverse connection treatment. By using the reverse polarity pairing after clockwise and counterclockwise pairing of the winding body, the induced voltage and potential difference within the same slot are canceled out from the electromagnetic source. Based on the potential difference distribution, bushings extending into the coil side and beyond the retaining wall are configured for some outgoing lines, strengthening the insulation depth and creepage distance of critical parts. Building upon this foundation, the interlayer insulation coating, with its width adapted and the termination crossing the center of the window, along with the strict prohibition of wiring connections across retaining walls, further eliminates weak points in insulation and the risk of mechanical interference. Ultimately, the mechanical strength of the electrical connection is ensured by adjusting the number of coils in the PIN winding based on wire diameter variations. This effectively solves the technical problems encountered in transformer applications with high reliability requirements or complex multi-winding structures, especially in scenarios where multiple windings need to be drawn from the same slot. Due to potential differences between windings, improper wiring can easily lead to localized electric field concentration in the confined slot space, causing insulation breakdown or short-circuit faults. Furthermore, traditional processes often struggle to maintain consistency in the positioning of the winding termination, the control of the lead-out angle, and the fit between the bushing and retaining wall, easily resulting in loose coil structures, bushing slippage, or core assembly interference. These issues ultimately affect the overall product yield and long-term operational stability. Therefore, this solution avoids breakdown short circuits, bushing slippage failures, and core assembly interference caused by potential differences, improving the electrical safety, structural reliability, and manufacturing consistency of transformer products. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1A flowchart illustrating a method for preventing short circuits in the forward and reverse wiring of a transformer with multiple windings in the same slot, provided as an embodiment of this application; Figure 2 A schematic diagram illustrating alternating dense and sparse winding arrangements at designated locations according to an embodiment of this application; Figure 3 This is a schematic diagram of the positive and negative wiring provided in an embodiment of this application; Figure 4 This is a schematic diagram illustrating the interlayer insulation coating width matching and end overlap suppression for preventing warping, provided in an embodiment of this application. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0018] Furthermore, the term "and / or" in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this article, unless otherwise specified, generally indicates that the preceding and following related objects have an "or" relationship.

[0019] The embodiments of this application will now be described in further detail with reference to the accompanying drawings.

[0020] The specific implementation method can be referred to in the following embodiments, wherein the data mentioned in the embodiments are only for reference and examples, so that relevant personnel can better understand them.

[0021] Figure 1 A flowchart illustrating a method for short-circuit protection winding of a transformer with multiple windings in the same slot, as provided in an embodiment of this application, is shown below. Figure 1 The process, specifically the implementation steps, are as follows: Example 1: In some embodiments, this application provides a method for short-circuit protection winding of a transformer with multiple windings in the same slot and reverse connection, the method comprising: Step S1: Install retaining walls on the transformer frame, ensuring that the retaining walls are flat, tight, and close to both sides of the frame.

[0022] The retaining wall, serving as a physical isolation structure defining the winding area and providing electrical safety creepage distances, is typically made of insulating tape. During installation, it is crucial to ensure the retaining wall material adheres tightly to the transformer frame sidewalls and edges, maintaining a flat surface and avoiding any loose application, folding, or misalignment to guarantee the accuracy of the winding space's geometric dimensions. This installation process can be achieved manually with the aid of a fixture to ensure the tape's direction is parallel to the frame axis; alternatively, an automated winding equipment's tape application module can be used to precisely control the tape tension and position. This flat and tight installation method effectively prevents the enameled wire from slipping onto the retaining wall tape during subsequent winding, ensuring the stability of the winding structure and compliance with safety regulations.

[0023] Step S2: Wind at least two sets of multiple windings that need to be led out from the same wire slot in the skeleton winding window. Each winding is arranged according to the corresponding winding area and winding density. Each winding is densely wound at a designated position. The end of each winding is set on the side close to the retaining wall.

[0024] The bobbin winding window is the physical space to accommodate the enameled wire. Designated-position close winding refers to a process where the enameled wire is concentrated in a specific area of ​​the window (such as the bottom, middle, or top) and tightly arranged. Compared to uniform or full-layer sparse winding, this process helps reduce leakage inductance and optimize coupling characteristics. When winding multiple sets of windings, the ends (tail wires) of each winding must be uniformly guided to the side near the retaining wall to provide space for subsequent unified lead-out. This winding process can be completed in time using a single-axis winding machine, i.e., winding each winding sequentially and fixing the end; alternatively, a multi-axis parallel winding device can be used to perform designated-position close winding of multiple sets of windings on the same or different layers under the coordination of the control system. By uniformly arranging the end wires near the retaining wall, the messy distribution of the lead-out wires within the window is avoided, facilitating subsequent wire management operations.

[0025] Step S3: Pull the end of each winding at a right angle and lead it out into the same wire slot.

[0026] The right-angle bending operation aims to bend the end of the enameled wire from a tangential or parallel direction to a 90-degree angle perpendicular to the winding plane, allowing it to directly enter the lead-out channel. During execution, the bending radius and force must be strictly controlled to ensure the enameled wire film is not damaged, and that the lead-out path points directly to the target wire groove. This bending process can be done manually using specialized wire bending pliers or tweezers with the edge of the frame as a fulcrum; alternatively, the end effector of an automated winding machine's robotic arm can be used to precisely pull the enameled wire to form a right angle along a preset trajectory. By bending the end to a right angle and introducing it into the same wire groove, multiple wires are initially converged in physical space, and the right-angle structure helps to fix the wire position, preventing springback or loosening.

[0027] Step S4: Perform forward and reverse connection processing on multiple winding leads drawn from the same wire slot, and configure bushings for some leads according to the potential difference between each lead in the wire slot. When configuring bushings, the bushings extend into the coil side and pass through the inside of the retaining wall.

[0028] Reverse connection processing is an operation based on the polarity difference (clockwise or counterclockwise) during winding. It involves matching the polarity of different winding leads from the same slot, aiming to cancel or balance potential interference under specific conditions through reverse connection pairing, rather than simply changing the physical connection direction. The bushing is usually heat-shrink tubing or silicone tubing, used to enhance the insulation performance of the leads. Bushing configuration requires considering the potential difference between the leads within the slot; bushings are added to lead combinations with a high potential difference risk to prevent breakdown and short circuits. During installation, the bushing must not only cover the exposed part of the lead but also extend towards the coil side and beyond the inner edge of the retaining wall, forming deep insulation protection. Reverse connection processing can be achieved by using testing instruments to identify the same-name and different-name terminals and connecting terminals with opposite polarities during the pin-hanging stage; alternatively, the polarity relationship can be preset during the winding stage, and the wires can be directly paired according to the rules during wire arrangement. Bushing configuration can be pre-inserted into the lead and pushed into the specified depth after wire arrangement; or automated equipment with expansion tools can be used to automatically install the bushing and ensure it extends beyond the inner edge of the retaining wall. By combining positive and negative wiring with deep bushing configuration, the potential short circuit hazard caused by potential difference in wires exiting the same slot is effectively solved, thus improving electrical reliability.

[0029] Step S5: Complete the remaining interlayer insulation wrapping and wiring work, and then perform the soldering process after connecting the outgoing wires to the pins.

[0030] Interlayer insulation wrapping is a process of wrapping insulating tape between winding layers to isolate different winding layers and prevent interlayer breakdown. The tape must cover the width of the winding, and the end is usually placed on the core assembly side and crosses the center to prevent lifting. Wiring is the process of organizing, fixing, and routing all outgoing wires on the transformer frame, ensuring clear routing, no interference, and that the enameled wire does not cross over the retaining wall tape. The bending directions of the outgoing wires are staggered. PINs are metal terminals on the transformer frame used to connect to external circuit boards. The soldering process uses molten solder to electrically and mechanically connect the enameled wire to the PINs. This process can be done by dip soldering, immersing the PINs in a molten solder bath, or by wave soldering or selective wave soldering for precise soldering. Through interlayer insulation wrapping, standardized wiring, and reliable soldering connections, a complete mechanical structure and electrical path are formed in the transformer, ensuring the insulation performance and connection stability of the product under complex operating conditions.

[0031] In the aforementioned technical solution, the flat and tightly sealed retaining wall provides a stable physical boundary and a safety basis; the unified layout of the tightly wound sections at designated locations and the termination points ensures the orderliness of the outgoing line positions; the right-angle lead-out process achieves spatially organized current convergence for multi-winding outgoing lines; the positive and negative connection treatment reduces the potential difference risk between outgoing lines in the same slot from the perspective of electrical polarity, while the bushing configuration that extends beyond the inner side of the retaining wall constructs a deep insulation barrier; finally, the interlayer insulation coating and wire soldering processes solidify the overall structure. These technical features work together to solve the short-circuit problem caused by insufficient insulation distance and potential difference in the narrow space of multi-winding outgoing lines in the same slot, while optimizing the production process and improving the overall quality and yield of the transformer.

[0032] Example 2: In one embodiment, this application also provides a parameter control method for setting up retaining walls. By precisely controlling the physical dimensional parameters of the retaining walls, it is ensured that the retaining walls can stably isolate the winding area and prevent abnormal displacement of the enameled wire during winding or subsequent processing.

[0033] The gap between the beginning and end of the retaining wall should be controlled to be no more than 1mm.

[0034] The gap at the beginning and end of the retaining wall refers to the non-overlapping area or unclosed gap formed between the first and last turns of tape when the retaining wall tape begins and ends winding on both sides of the winding frame. This gap size should be strictly controlled to no more than 1mm, for example, it can be controlled to 0.8mm, 0.5mm, or 0mm (i.e., complete overlap). Limiting the gap to a small area aims to avoid forming excessively large unobstructed areas on both sides of the frame, thus preventing the enameled wire from slipping into the gap under winding tension, or causing the retaining wall structure to loosen due to an excessively large gap. If the gap is too large, the enameled wire may slip into the gap at the beginning and end of the retaining wall, violating the originally set safety distance; by controlling the gap to within 1mm, the adhesive force of the tape can be effectively used to close the edges, ensuring that the frame edges are completely covered by the retaining wall, thereby maintaining a stable winding space boundary.

[0035] The height of the retaining wall is matched with the height of the winding to prevent the enameled wire from slipping onto the retaining wall tape.

[0036] When determining the height of the retaining wall, it should be adapted to the actual height of the winding to be wound. Specifically, the height of the retaining wall should be equal to or slightly higher than the overall height of the winding after completion, to ensure that the top of the retaining wall is always higher than or flush with the upper surface of the outermost enameled wire in the vertical direction of the entire winding window. This height adaptation relationship creates a physical barrier. When the winding machine is performing wire laying operations or handling the coil in subsequent processes, even if the enameled wire is subjected to external pressure or tends to slip laterally due to tension rebound, the sidewall of the retaining wall can effectively prevent the enameled wire from crossing the retaining wall boundary. If the height of the retaining wall is lower than the winding height, the enameled wire may climb over the top of the retaining wall and slide onto the adhesive surface of the retaining wall tape. This will not only lead to messy winding arrangement and damage to the interlayer structure, but may also introduce insulation safety hazards due to the enameled wire directly contacting the tape adhesive. By maintaining the compatibility between the height of the retaining wall and the height of the winding, the enameled wire can be strictly confined within the preset winding area, ensuring that it is always within the effective range of the winding body and cannot slip onto the retaining wall tape. This guarantees the regularity of the winding structure and the necessary safe electrical clearance between each winding and between the winding and the frame.

[0037] Example 3: In one embodiment, this application provides a winding strategy in which at least two sets of windings are wound in the same slot using a time-sharing method. Under this strategy, one set of windings is wound in a clockwise direction, and the other set of windings is wound in a counterclockwise direction. Each set of windings is arranged at the bottom, middle, or top of the bobbin winding window. When three or more sets of windings need to be led out from the same slot, the winding directions of the multiple sets of windings are alternately configured in a clockwise, counterclockwise, and clockwise manner.

[0038] The term "multi-set co-slot time-sharing winding" refers to winding multiple independent windings sequentially at the same height level within the bobbin winding window, rather than simultaneously winding them in parallel. The vertical distribution of each winding within the window is determined by the transformer design requirements and can be flexibly arranged at the bottom, middle, or top. For example, in a double-layer winding structure, one winding can be located at the bottom of the winding window, and the other at the top; while in a multi-layer winding structure, the windings can be distributed at different levels, such as the bottom, middle, and top of the window. During the winding process, the winding direction of each winding is strictly controlled, with one winding wound clockwise and the other counterclockwise.

[0039] For situations where three or more windings need to be drawn from the same slot, to avoid exacerbating the superposition of leakage flux due to multiple windings having a single winding direction, the winding directions of the multiple windings are configured in an alternating pattern. Specifically, the winding directions are arranged in a clockwise, counterclockwise, and clockwise alternating sequence. Through this alternating configuration, the leakage magnetic field generated by different windings in adjacent or nearby positions tends to be in opposite directions when energized, thereby creating a partial cancellation effect in physical space and effectively reducing the overall induced electromotive force and potential gradient in the slot area.

[0040] Based on the above-mentioned technical solution of multiple sets of time-sharing winding in the same slot and alternating winding direction, the electromagnetic interference between multiple windings in the same slot can be effectively balanced, the risk of short circuit caused by excessive potential difference can be reduced, and the electromagnetic compatibility performance and heat distribution uniformity inside the transformer can be optimized.

[0041] Example 4: In one embodiment, this application provides a specific arrangement strategy for winding density, which is configured differently for different combinations of winding numbers, aiming to balance the mechanical stress distribution of the coil with electrical performance requirements.

[0042] Step 1: When there are two sets of windings, one set of windings is densely wound at a designated position, and the other set of windings is sparsely wound at full layer. The end of both sets of windings is set on the side close to the retaining wall.

[0043] For transformer structures with two sets of windings, a combination of close winding at designated locations and sparse winding across full layers is used to optimize the physical morphology of the coils while meeting electrical parameters. Close winding at designated locations refers to a winding method in which the copper wires are arranged without gaps in a specific area of ​​the winding window (such as the middle area or a specific layer). The copper wires are tightly arranged, which can effectively utilize the limited window space and ensure that the number of turns per unit length meets the design requirements, thereby satisfying the electrical indicators of inductance and coupling.

[0044] The accompanying full-layer loose winding is a uniformly distributed winding method, with pre-set gaps between the turns, rather than tight bonding. In practical engineering applications, the tightness of the loose winding can be adjusted according to the wire diameter, for example, it can be 1.1 to 1.5 times the wire diameter spacing, to prevent disordered slippage of the enameled wire during subsequent interlayer insulation coating or high-temperature soldering, thus maintaining the stability of the coil structure. The main function of the loose winding layer is to adjust the thickness of the coil, especially in multi-layer winding scenarios. A single tight winding will cause the thickness of the coil belly to increase sharply, forming a "bulge" phenomenon, which not only occupies too much skeleton window space, but may also cause the interlayer insulation tape to be overstretched and break. By introducing a loose winding layer, the winding tension can be effectively released, the radial pressure between layers can be relieved, the overall thickness of the coil can be reduced, and the appearance of the coil can be made flatter, which is beneficial to the subsequent magnetic core assembly process.

[0045] While the order of close winding and loose winding is not strictly defined in terms of arrangement, in practice, the close-wound layer is usually placed in the main coupling area (such as the middle layer), while the loose-wound layer is placed in the transition area or edge layer to buffer stress. Regardless of the specific spatial distribution, the finishing ends of both sets of windings are strictly set on the side closest to the retaining wall. This uniformity of the finishing position ensures that the wires from each winding in subsequent steps can converge to the same wire slot along the same path, avoiding the wires crossing the coil body due to inconsistent finishing end positions, thereby reducing the risk of short circuits.

[0046] Step 2: When there are three or more sets of windings, the windings are arranged alternately in the order of dense winding at a specified position, sparse winding at full layer, and dense winding at a specified position. The end of all windings is set on the side closest to the retaining wall.

[0047] The control of winding density was extended to multi-winding scenarios. By alternating patterns of dense winding at designated locations, sparse winding in full layers, and dense winding at designated locations, a coil structure with periodic physical characteristics was constructed. In this alternating arrangement, the densely wound layer, as a high-density filler layer, mainly undertakes the function of establishing the magnetic field and realizing energy transmission. Its tight structure ensures the coupling coefficient between windings. The sparsely wound layer, as a low-density buffer layer, is interspersed between the densely wound layers. The micro-gaps inside provide space for thermal expansion and contraction of the enameled wire, and also serve as a buffer strip for the attachment of insulating tape, preventing the densely wound layer from directly squeezing adjacent layers under radial pressure.

[0048] From a mechanical transmission perspective, during multi-layer winding, the inner windings are subjected to radial compressive forces from the outer windings. If all layers are tightly wound, this compressive force will linearly accumulate layer by layer radially, causing deformation of the innermost copper wires or even being pressed into the bobbin separator, leading to a short circuit. By inserting loosely wound layers, due to the gaps between the internal turns, the loosely wound layers possess a certain degree of compressibility, acting like a spring to absorb and attenuate the radial pressure transmitted from the outer layers, thus protecting the inner tightly wound structure from excessive compression. Furthermore, this alternating hard and soft structure (the tightly wound layers are harder, and the loosely wound layers are softer) can effectively suppress the eccentricity of the coil during winding, maintaining the roundness or regularity of the coil cross-section.

[0049] In practice, the winding equipment needs to automatically adjust the wire arrangement parameters according to the preset number of winding layers and winding mode. For example, when performing full-layer loose winding, the servo motor of the winding machine will control the wire arrangement step distance to increase, so that the spacing between the wires remains fixed; while when switching back to the designated position for tight winding, the step distance is reduced to zero or close to zero, restoring a tight arrangement. Figure 2As shown, this alternating pattern visually presents a clear difference in texture; the densely wound areas are smooth and clean, while the sparsely wound areas reveal regular inter-wire textures. Regardless of the number of windings, this alternating cycle always follows the above rule until all windings are completed. Crucially, the ends of all windings must converge uniformly on the side closest to the retaining wall. This design allows the leads of different windings to be spatially layered and stacked, but with their ends unified. The leads remain parallel and close to the inner side of the retaining wall, providing a uniform physical basis for subsequent bushing configuration and forward / reverse wiring, ensuring the electrical safety and process consistency of the final product.

[0050] Example 5: In one embodiment, the method includes: when pulling the end of each winding out at a right angle, ensuring that the winding wires enter and exit the slots without exceeding the frame radius (R angle) to avoid interference during subsequent magnetic core assembly.

[0051] The bobbin radius (R-angle) refers to the arc-shaped transition area formed at the junction of the winding window and the pins of the transformer bobbin. This area is both a stress concentration point in the bobbin's mechanical structure and the main guiding and fitting path during core assembly. When pulling the winding end out at a right angle, the spatial trajectory of the lead wire must be strictly controlled. Specifically, after the winding end is bent and pulled out from one side of the retaining wall, it should closely conform to the geometric contour of the bobbin surface, ensuring that the enameled wire is inside the arc of the R-angle area when passing through it, and that the overall height and extension direction of the lead wire are constrained by the sidewall of the slot.

[0052] By strictly limiting the entry and exit paths of the winding leads to the inside of the frame's radius (R-angle), a safe and uniform physical gap can be maintained between the leads and the frame. This gap provides necessary clearance for subsequent core assembly processes, ensuring that the core does not come into contact with the winding leads during pressing or sliding into the frame. This measure avoids damage to the enameled wire insulation layer caused by mechanical interference, effectively preventing short circuits between turns or between turns and the core, while also ensuring the fitting accuracy and assembly yield of the core and frame.

[0053] Example 6: In one embodiment, such as Figure 3 As shown, this application provides a schematic diagram of positive and negative wiring, and also provides the specific technical content of performing positive and negative wiring processing.

[0054] The reverse connection process is characterized by pairing different winding leads from the same slot with reverse polarity after clockwise and counterclockwise pairing of the winding body. This is to distinguish it from the connection method that simply changes the physical direction of the lead-in pins and does not match the winding polarity of the winding body.

[0055] This processing method does not merely change the physical connection order of external pins, but rather, based on the winding polarity (i.e., clockwise or counterclockwise winding) determined during the physical winding stage of the winding body, it performs electrical polarity matching and reverse connection configuration for multiple outgoing wires drawn from the same slot. After the two winding bodies are wound in clockwise and counterclockwise directions respectively, the direction of their internal magnetic field induction is determined. At this point, the outgoing wires of these two windings are electrically reversed, so that the current flowing through the two outgoing wires in the same slot at the same time is in opposite directions, thereby canceling the induced voltage generated by the potential difference at the electromagnetic level.

[0056] This wiring method is fundamentally different from simply swapping the physical orientation of the lead wires. The latter only changes the physical position of the external terminals without altering the electrical connection between the winding leads and the winding body's polarity, thus failing to eliminate the risk of short circuits caused by polarity differences. The method described above ensures deep coupling between the winding's electrical polarity and physical winding characteristics, fundamentally suppressing the potential for short circuits caused by polarity mismatch between leads in the same slot.

[0057] Example 7: In one implementation, this application provides a method for configuring a sleeve flush groove and preventing slippage, the method comprising: Step 1: Configure the outlet of the sleeve. The sleeve must be flush with the B / N groove opening of the skeleton and reach at least two-thirds of the groove height.

[0058] During the configuration of bushing leads, it is essential to ensure that the bushing end is flush with the B / N (Base) groove opening of the frame, and that the bushing coverage height is no less than two-thirds of the overall groove height. The B / N groove opening, as a critical channel for transformer pin leads, serves as the starting reference point for measuring electrical clearances and creepage distances. As a reinforcing insulation component, the bushing's assembly position directly determines the effectiveness of insulation protection. By ensuring that one end of the bushing strictly covers and is flush with the edge of the B / N groove opening, it is possible to completely enclose the exposed conductor starting from the pin root, eliminating insulation blind spots. Furthermore, given that the lead root and groove edge within the groove's internal structure are areas of concentrated electric field stress, insufficient bushing height leading to upper space can easily cause flashover or surface discharge between the bushing's upper edge and the groove opening under high-voltage conditions. Setting the bushing height to at least two-thirds of the groove height effectively blocks creepage paths from the pin to the frame or adjacent conductors, thereby meeting the insulation distance requirements of transformer safety standards and improving the product's withstand voltage and operational reliability.

[0059] Step 2: Insert the fly wire type lead wire sleeve into the B / N bend position of the frame to prevent the sleeve from slipping off the lead wire.

[0060] For flying lead wires, the bushing is extended into the bend at the B / N position of the frame to prevent slippage of the bushing from the lead wire. Flying lead wires typically refer to connecting wires that do not directly adhere to the frame winding but cross a certain space. These wires are easily subjected to pulling or external disturbances during assembly, transportation, or subsequent welding. The bend at the B / N position of the frame, where the lead wire changes direction on the base or foundation, is both a critical support point for the flying lead and a high-risk area where the bushing is prone to displacement or even detachment. By forcibly extending the bushing deep into the bend, the geometry of the bend creates a mechanical self-locking or anchoring effect. When the bushing end is tightly against the inner wall of the bend, it is physically blocked and constrained by the frame structure. Even if the lead wire is subjected to external axial tension, the bushing is unlikely to overcome this resistance and slide back. This structural design effectively solves the problem of conductor exposure caused by bushing slippage in flying lead wires, avoiding electrical short circuits, breakdowns, or safety hazards, and ensuring the electrical connection stability of the transformer under complex operating conditions.

[0061] The aforementioned technical features work synergistically to construct a complete spatial positioning and anti-slip mechanism by precisely limiting the height coverage of the bushing at the B / N groove opening of the frame and the insertion depth at the bend of the flying wire. The former ensures adequate insulation protection and avoids the risk of discharge in areas of concentrated electric field; the latter utilizes the geometric features of the frame to achieve mechanical fixation, avoiding insulation failure caused by bushing displacement. Combined, these two aspects, while meeting stringent safety regulations for insulation, eliminate potential failure points caused by improper bushing installation from both structural and process perspectives.

[0062] Example 8: In one implementation, such as Figure 4 The diagram shown illustrates the interlayer insulation tape width matching and end overlap suppression of warping provided in this embodiment of the application. The method further includes: the tape width of the interlayer insulation tape is equal to the width of the bobbin winding; the end overlap edge of the tape is arranged on the core assembly side, and the end of the tape crosses the center of the bobbin winding window to suppress tape warping.

[0063] Step 1: The width of the interlayer insulation tape is equal to the width of the skeleton winding.

[0064] Interlayer insulation coating aims to ensure the withstand voltage insulation strength between transformer windings and facilitate subsequent winding operations. The dimensional fit between the width of the interlayer insulation tape and the width of the bobbin winding directly determines the morphological stability and coverage of the insulation layer edge. The tape width is precisely matched to the bobbin winding width, ensuring they are equal or slightly larger. In practice, the width of the interlayer insulation tape is set equal to the bobbin winding width, but not less than it. This equal or slightly wider configuration allows the tape's side edges to fit tightly against the winding area or maintain appropriate coverage when covering the coil surface. This avoids exposed insulation on the coil sides due to excessively narrow tape, or material waste and interference with surrounding structures due to excessively wide tape. By controlling the tape width to equal the bobbin winding width, the axial continuity and integrity of the insulation layer are ensured, providing a flat winding base for the enameled wire and effectively eliminating the risk of partial discharge caused by suspended tape edges or dimensional mismatch.

[0065] Step 2: The overlapping edge of the tape is placed on the magnetic core assembly side, and the end of the tape crosses the center of the bobbin winding window to prevent the tape from lifting.

[0066] The finishing of the tape is a critical step affecting the long-term reliability of the insulation layer. Improper handling can easily cause the tape end to curl up, fold back, or detach, thereby compromising insulation performance and hindering subsequent core assembly. These risks can be mitigated by limiting the specific spatial location of the tape end. First, the tape end overlap is strictly positioned on the core assembly joint side, i.e., the side where the upper and lower parts of the core are joined. This location is chosen because during subsequent core assembly, this joint side is usually wrapped or in internal contact. The core's clamping force or structural shielding provides physical protection and fixation for the tape end, preventing accidental scratching or lifting during transportation or assembly. Second, the tape end is controlled to cross the center of the bobbin winding window. The center of the bobbin winding window is the geometric axis of symmetry of the coil width. The tape end crossing this center point means that the tape retains sufficient length margin at the end, allowing the area extending from the center point to the edge to form an effective self-locking or covering structure. This cross-center arrangement alters the stress state of the tape end, balancing and suppressing its rebound force or warping tendency with the bonding area on the other side of the centerline, thus preventing edge lifting of the tape due to internal stress release. By confining the end overlap to the magnetic core assembly side and forcing the tape end to cross the center of the winding window, a robust insulating encapsulation structure is formed. This structure not only avoids assembly interference through physical positioning but also eliminates the driving force for tape lifting using the principle of mechanical balance, thereby ensuring long-term flatness and effectiveness of interlayer insulation.

[0067] The aforementioned technical features work synergistically to solve the insulation failure problem caused by tape width mismatch and unreasonable end position in traditional processes. By precisely controlling the consistency between the tape width and the winding width, the hidden danger of edge stress concentration is eliminated; by placing the overlapping edge on the core assembly side and crossing the center position, the tape end is locked using a dual mechanism of structural position and mechanical balance. This combination ensures that the interlayer insulation tape remains flat and tightly attached throughout winding, assembly, and subsequent use, effectively suppressing tape warping, avoiding the risk of interlayer short circuits caused by insulation layer damage, and improving the electrical safety and production yield of the transformer.

[0068] Example 9: In one embodiment, this application provides a wiring operation specification for a transformer with multi-winding output in the same slot and reverse connection for short-circuit protection winding, the method specifically including: Step 1: Control the wiring path of the enameled wire within the frame winding window, and prohibit the enameled wire from crossing over the retaining wall tape.

[0069] During the wiring process, the wiring path of the enameled wire is strictly limited to ensure that all enameled wires are arranged within the effective winding area of ​​the bobbin winding window and are completely within the safety space defined by the retaining tape. The retaining tape is mainly used to establish a safe distance for winding; its edges and surfaces are not designed as the main insulator to support the conduction path of the enameled wire. If the enameled wire is bridging the retaining tape, the winding tension can easily cause the tape edges to warp, shift, or break, thus violating the safety distance requirements. In addition, the enameled wire bridging the retaining tape is often in an abnormally suspended or taut state, which can easily cause friction during subsequent core assembly or transportation vibrations, leading to enamel film damage and causing interlayer or inter-turn short circuits. Through the above wiring process constraints, using the retaining tape to provide stable physical support and isolation barrier for the winding can effectively avoid such short circuit risks.

[0070] Step 2: Control the bending direction of each winding lead so that the multiple lead wires in the slot are staggered.

[0071] For multiple winding leads originating from the same slot, their bending direction is precisely controlled, resulting in a staggered arrangement of the leads within the slot. When multiple leads from different windings emerge from the same slot, if all leads are bent and arranged close together in the same direction and angle, they are prone to close contact or even overlap within the narrow slot space. This can cause molten solder to flow and short-circuit adjacent leads during soldering. By controlling the bending direction of each winding lead, for example, guiding adjacent leads to tilt towards different sidewalls of the slot as they leave, or creating upper and lower layers through slight differences in bending angles in the vertical direction, this staggered arrangement significantly increases the air gap and surface creepage distance between adjacent leads, keeping them physically separated. This effectively blocks the risk of short circuits caused by solder overlap or wire insulation damage without adding additional insulation material. Furthermore, the staggered arrangement helps to streamline the lead routing, improving the ease and neatness of subsequent pin connection operations.

[0072] Step 3: If the starting and ending ends of the winding are on the same side of the frame, place insulating tape in advance before folding back the ending end to hang the pin.

[0073] In the actual winding process of a transformer, if the starting and ending ends of a certain winding happen to be located on the same side of the frame, the winding usually needs to be distributed in multiple layers using the height space of the winding window, or the ending end needs to be brought back to the starting side for connection via a fold-back path. In this case, the ending end inevitably needs to cross or approach other layers of windings (including its own starting end or the turns of other windings) on the path of folding back to connect the pin. If the ending end is folded back directly, due to the rigidity of the enameled wire itself and the stress concentration at the bend, it is very easy to break the enamel film of the lower layer winding turns, or form a tight contact at the intersection of the starting and ending ends, leading to the risk of short circuit due to the pinhole effect. To address this problem, before folding back the ending end to connect the pin, insulating tape is placed between the fold-back path of the ending end and the lower layer winding or the starting end. This insulating tape acts as a physical insulation barrier, not only covering potential electrical contact points but also providing a smooth buffer layer. This transforms the sliding friction of the enameled wire at the termination end into rolling friction during bending, preventing scratches or punctures to the insulation layer of the underlying enameled wire. This pre-placement of insulating tape structurally and completely blocks electrical short-circuit paths between the starting and ending ends of the winding, as well as between the termination end and the underlying winding, ensuring the insulation reliability of the transformer under high-voltage conditions.

[0074] Example 10: In one implementation, when the outgoing wire is connected to the PIN, the number of coils is determined based on the diameter of the enameled wire. For wires with a diameter greater than 0.6mm, wrap at least 0.8 turns; for wires with a diameter equal to 0.6mm, wrap at least 0.8 turns; for wires with a diameter greater than 0.32mm and less than 0.6mm, wrap at least 1.5 turns; for wires with a diameter equal to 0.32mm, wrap at least 2.5 turns; and for wires with a diameter less than 0.32mm, wrap at least 2.5 turns. Ensure the knot is tightly wrapped.

[0075] The diameter of enameled wire refers to the diameter of the copper conductor used for winding transformer windings after it has been coated with an insulating enamel layer. This dimension directly determines the conductor's physical stiffness, tensile strength, and contact friction characteristics during winding. The number of turns refers to the number of turns the enameled wire makes around the pin when fixing the winding lead to the pin. This parameter determines the mechanical locking force and conductive contact area at the connection point. Tight winding refers to the physical state where the enameled wire fits tightly against the pin without any loose gaps, ensuring a stable electrical connection during subsequent soldering processes and long-term use.

[0076] For applications using enameled wires with a diameter greater than 0.6mm, the large cross-section and high rigidity of the conductor result in significant inertia and reduced deformation during winding. The mechanical engagement force between the wire and the pin relies primarily on the wire's inherent rigidity rather than multi-turn friction. By setting a minimum winding length of 0.8 turns (allowing for less than one turn), the physical property of the thicker wire preventing slippage is utilized. This reduces excessive winding while maintaining mechanical stability, thus preventing warping or compression damage to the pin base due to excessive wire diameter stacking.

[0077] For scenarios where the enameled wire diameter is 0.6mm, which is a critically large wire diameter, the conductor cross-section and rigidity are already close to those of large-diameter wires, making conductor deformation difficult. The conductor's own structure can provide sufficient mechanical support. By setting a parameter of at least 0.8 turns, the pins are positioned and fixed by relying on the rigidity of the conductor itself. This eliminates the need for excessive turns, ensuring mechanical strength after connection while preventing excessive copper wire stacking at the pins from causing space constraints and pin deformation.

[0078] For medium-diameter enameled wires (greater than 0.32mm and less than 0.6mm), where the wire cross-section and stiffness fall between those of thick and thin wires, the wire possesses a certain structural strength. However, its stiffness is insufficient to achieve reliable positioning with only about half a turn of winding. Too few turns can lead to wire wobbling and poor contact, while too many turns can cause copper wire accumulation at the pins. By setting a minimum of 1.5 turns, the contact friction from an appropriate number of turns is used to lock the wire in place, balancing operational efficiency in the on-site winding process and avoiding the potential for loose connections and poor soldering in this section of the wire.

[0079] For applications requiring a critically fine wire diameter of 0.32mm, the wire is relatively soft and has limited resilience. When subjected to external forces, the lead wire is prone to displacement and loosening, resulting in a small contact area and insufficient contact stability. By setting a minimum of 2.5 turns for the wire to create sufficient frictional grip, the contact area between the wire and the pin is increased, counteracting the wire's rebound tendency and ensuring a secure connection at the joint.

[0080] For applications involving enameled wires with a diameter less than 0.32mm, the wire's softness and low stiffness make it prone to springback or slippage during winding, and the small contact area can lead to excessive contact resistance. By setting a minimum of 2.5 turns, the accumulated friction from multiple turns and the mechanical constraint of the binding knot increase the effective contact area and frictional resistance between the thin wire and the lead, thus overcoming the problem of loosening. This process dynamically adjusts the number of turns based on the wire diameter, ensuring that enameled wires of different specifications achieve the appropriate tightening standards.

[0081] The above processing logic aims to precisely match the physical properties of the conductor with the winding process parameters through quantitative standards. Based on the wire diameter of the enameled wire to be connected, a corresponding winding loop number threshold is matched, and the winding action is controlled to meet this threshold, ensuring that both thick and thin wires obtain a fixing force adapted to their mechanical properties. This differentiated parameter setting achieves the dual technical effect of preventing excessive winding damage to the pins of thick wires and enhancing the locking effect of thin wires through multiple windings. This ensures that the winding outputs of various wire diameters remain tightly wound after being connected to the pins, effectively preventing potential wire breakage risks caused by improper winding loop number, such as poor soldering, cold soldering, or transportation vibration.

[0082] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for preventing short circuits by reverse wiring of a transformer with multiple windings in the same slot, characterized in that, include: S1. Install retaining walls on the transformer frame, making the retaining walls flat, tight and close to both sides of the frame; S2. At least two sets of multiple windings that need to be led out from the same wire slot are wound in the skeleton winding window. Each winding is arranged according to the corresponding winding area and winding density. Each winding is densely wound at a specified position. The end of each winding is set on the side close to the retaining wall. S3. Pull the end of each winding at a right angle and lead it out into the same wire slot; S4. Perform forward and reverse wiring treatment on multiple winding leads drawn out from the same wire slot, and configure sleeves for some leads according to the potential difference between each lead out in the wire slot. When configuring the sleeves, the sleeves extend into the coil side and pass through the inside of the retaining wall. S5. After completing the remaining interlayer insulation coating and wiring work, connect the outgoing wires to the pins and then perform the soldering process.

2. The method according to claim 1, characterized in that, When setting up the retaining wall, the gap between the beginning and end of the retaining wall should be controlled to be no more than 1mm, and the height of the retaining wall should be matched with the height of the winding to prevent the enameled wire from slipping onto the retaining wall tape.

3. The method according to claim 1, characterized in that, The at least two sets of windings are wound in the same slot at different times, with one set of windings wound clockwise and the other set of windings wound counterclockwise. Each set of windings is arranged at the bottom, middle or top of the skeleton winding window. When three or more windings need to be led out from the same slot, the winding directions of the multiple windings are alternately configured in a clockwise, counterclockwise, and clockwise manner.

4. The method according to claim 1, characterized in that, When the multiple sets of windings are two sets of windings, one set of windings is densely wound at a designated position, and the other set of windings is sparsely wound at full layer. The end of both sets of windings is set on the side close to the retaining wall. When there are three or more sets of windings, the windings are arranged alternately in the order of dense winding at a specified position, sparse winding at full layer, and dense winding at a specified position, and the end of all windings is set on the side close to the retaining wall.

5. The method according to claim 1, characterized in that, When pulling the end of each winding out at a right angle, ensure that the winding wires enter and exit the slots without exceeding the frame radius (R angle) to avoid interference during subsequent core assembly.

6. The method according to claim 1, characterized in that, The aforementioned reverse connection processing is characterized by performing polarity reversal pairing on different winding leads from the same slot after clockwise and counterclockwise pairing of the winding body. This is to distinguish it from the connection method that simply changes the physical direction of the lead connection pins and does not match the winding polarity of the winding body.

7. The method according to claim 1, characterized in that, The outlet of the sleeve must be flush with the B / N groove opening of the skeleton and reach at least two-thirds of the groove height. The fly wire type lead-out sleeve extends into the B / N bend position of the skeleton to prevent the sleeve from slipping off the lead wire.

8. The method according to claim 1, characterized in that, The width of the interlayer insulating tape is equal to the width of the skeleton winding. The tape's overlapping edge is positioned on the core assembly side, and the tape end crosses the center of the bobbin winding window to prevent the tape from lifting.

9. The method according to claim 1, characterized in that, During the wiring operation, the enameled wire must not be crossed over the retaining wall tape. Control the bending direction of each winding lead so that the multiple lead wires in the wire groove are staggered. If the starting and ending ends of the winding are on the same side of the frame, place isolation tape in advance before folding the ending end back and hanging the pin.

10. The method according to claim 1, characterized in that, When the outgoing wire is connected to the PIN, the number of turns is determined according to the diameter of the enameled wire. For wires with a diameter greater than 0.6mm, wrap at least 0.8 turns; for wires with a diameter equal to 0.6mm, wrap at least 0.8 turns; for wires with a diameter greater than 0.32mm and less than 0.6mm, wrap at least 1.5 turns; for wires with a diameter equal to 0.32mm, wrap at least 2.5 turns; and for wires with a diameter less than 0.32mm, wrap at least 2.5 turns. Ensure the knot is tightly wrapped.

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