Anti-short-circuit oil-immersed three-dimensional wound core transformer

Abstract

The application discloses an anti-short-circuit oil-immersed three-dimensional wound core transformer and relates to the technical field of transformers. The transformer comprises a body formed by a three-dimensional wound core, a high-voltage coil and a low-voltage coil, and a clamping piece for supporting and connecting; the body is compressed by a full-pressure arc-shaped pressing plate, and a supporting plate for enhancing the overall mechanical strength is filled between the core window and the arc-shaped pressing plate and between the core and the insulating cylinder of the low-voltage coil; the body is finally compressed by a center rod which is screwed; the transformer further comprises an inductance module integrated in the oil tank of the transformer by an insulating support, the module is led out by independent sealed wiring terminals and connected to the low-voltage side loop of the transformer in a parallel mode. The anti-short-circuit oil-immersed three-dimensional wound core transformer has the mechanical strengthening arrangement of the full-pressure arc-shaped pressing plate, the filling of the supporting plates at multiple positions, the strengthened iron triangle plate and the compression of the center rod, and thus the short-circuit resistance of the transformer is enhanced.

Description

Technical Field

[0001] This invention relates to the field of transformer technology, and in particular to a short-circuit resistant oil-immersed three-dimensional wound core transformer. Background Technology

[0002] Power transformers bear the core function of voltage transformation and power conversion in the power grid, and their operational reliability is directly related to grid security and power supply quality. Conventional oil-immersed transformers typically consist of a core, windings, insulation, and oil tank, and their function is mainly limited to voltage level conversion and electrical isolation. These transformers have two significant limitations: first, their structural design often lacks sufficient mechanical strength to withstand sudden short-circuit currents, resulting in poor short-circuit withstand capability and a high risk of cascading power outages due to faults; second, as passive devices, traditional transformers lack the ability to dynamically compensate for reactive power or harmonics in the system in real time. With the large-scale integration of new energy sources and nonlinear loads into the grid, power quality issues are becoming increasingly prominent. The aforementioned limitations make it difficult for traditional transformers to meet the dual demands of modern power grids for high-reliability power supply and active power quality management.

[0003] To address this challenge, the industry has proposed integrating dynamic reactive power compensation or harmonic suppression functions into the transformer itself. For example, this can be achieved by using a built-in adjustable inductor module, enabling the transformer to perform voltage transformation while simultaneously regulating power quality. However, in adjustable inductors, as described in application number 202321619363.4, inductance adjustment is often achieved by rotating a magnetic core assembly. This type of "rotation insertion" adjustment often suffers from poor linearity and insufficient precision. A single insertion method cannot achieve smooth, continuous, and wide-range fine adjustment of the inductance.

[0004] Therefore, there are still shortcomings and deficiencies in the existing technology. How to provide a short-circuit resistant oil-immersed three-dimensional wound core transformer is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] The purpose of this invention is to provide a short-circuit resistant oil-immersed three-dimensional wound core transformer, which solves the technical problem that existing conventional oil-immersed transformers have limited short-circuit resistance and lack dynamic reactive power and harmonic regulation functions, making it difficult to meet the dual requirements of high equipment reliability and active power quality management in modern complex power grids.

[0006] To achieve the above objectives, the present invention provides a short-circuit resistant oil-immersed three-dimensional wound core transformer, comprising a three-dimensional wound core, a transformer body composed of a high-voltage coil and a low-voltage coil, and clamps for support and connection. The transformer body is compressed by a fully pressurized arc plate, and support plates to enhance the overall mechanical strength are filled between the core window and the arc plate, and between the core and the insulation cylinder of the low-voltage coil; the transformer body is finally compressed by a threaded central rod. The transformer also includes an inductor module integrated inside its tank via an insulating support. This module is led out through independent sealed terminals and connected in parallel to the low-voltage side circuit of the transformer. The inductor module is configured to achieve smooth and continuous adjustment of the module's inductance by radial displacement of multiple sets of axially arranged magnetic conductors relative to the coil.

[0007] Preferably, the inductor module includes a housing, a base, a coil disposed within the housing, and a magnetic guide assembly and a control mechanism for adjusting the inductance. The magnetic guide assembly consists of several magnetic sheets arranged along the axial direction of the coil. Each magnetic sheet has a tapered outer wall, with the end closer to the coil being the small end and the end farther from the coil being the large end. The control mechanism includes a drive component that can drive the magnetic sheets to move radially along the coil to change the effective area of ​​the tapered outer wall of the magnetic sheets extending into the coil turns.

[0008] Preferably, the driving assembly includes a linear moving part, a wedge block that moves axially driven by the linear moving part, and a guide rod that moves radially driven by the inclined surface of the wedge block. The guide rod is connected to the large end of the magnetic sheet. Both ends of the wedge block along its moving direction are set as symmetrical inclined surfaces.

[0009] Preferably, a guide wheel is rotatably mounted at the end of the guide rod, and the guide wheel contacts the inclined surface of the wedge block.

[0010] Preferably, the linear drive unit is a lead screw drive assembly, including a drive lead screw and a movable block fixed to the wedge block, the movable block being threadedly engaged with the drive lead screw.

[0011] Preferably, it also includes a reset assembly, which includes a base plate fixed on each guide rod and a retaining plate fixed to the side of the base plate; the free end of the retaining plate overlaps the side of the base plate of the adjacent guide rod; when a group of guide rods moves radially driven by a wedge, its base plate pushes the adjacent base plate through the retaining plate, thereby driving all the reset magnetic sheet groups to move synchronously.

[0012] Preferably, the guide rod slides through the baffle, the baffle is fixed on the base, and a spring is sleeved on the section of the guide rod between the baffle and the base plate. The two ends of the spring abut against the baffle and the base plate respectively, providing a restoring force for the guide rod.

[0013] Preferably, the overall length of the wedge is less than the distance between the guide wheels on the two adjacent guide rods, so that the wedge can move between the two sets of guide wheels to provide reset space for the working magnetic sheet group.

[0014] Preferably, the magnetic sheets are grouped together by connectors, which include an L-shaped base and a groove. The larger end of the magnetic sheet is installed in the groove by a fixed shaft, so that multiple magnetic sheets form a synchronous motion unit.

[0015] Preferably, one end of the drive screw extends to the outside of the transformer housing.

[0016] The present invention has the following advantages: (1) Compared with the above background technology, the present invention provides a series of mechanical reinforcement settings such as a full-pressure arc-shaped pressure plate, multiple support plates, reinforced iron triangle plate and central rod pressing of an anti-short circuit oil-immersed three-dimensional wound iron core transformer, which improves the overall rigidity and stress uniformity of the transformer body, enabling it to withstand the huge electrodynamic force generated during short circuit, thereby directly enhancing the short circuit tolerance of the transformer and reducing the risk of equipment damage and large-scale power outage caused by short circuit faults.

[0017] (2) Compared with the above-mentioned background technology, the short-circuit resistant oil-immersed three-dimensional wound core transformer provided by the present invention achieves continuous and precise control of inductance over a wide range through a dual adjustment mechanism of axial grouping and radial insertion depth of magnetic sheets. Axial adjustment covers a wide range of inductance changes by sequentially activating different magnetic groups, while radial adjustment achieves fine-tuning within each group by precisely controlling the insertion depth of a single magnetic sheet through the wedge-shaped inclined surface. This enables it to dynamically and smoothly adjust reactive power or suppress harmonics, effectively expanding the functional boundaries of traditional transformers and enhancing its active support capability in complex power grids. Furthermore, by setting a reset component and a locking plate, it ensures that multiple groups of magnetic sheets maintain synchronous insertion depth during the adjustment process, solving the problem of uneven magnetic field distribution caused by grouping actions. This allows the already working magnetic sheets to automatically reset before activating a new group, and then multiple groups are inserted in coordination, avoiding local magnetic saturation or concentrated eddy current losses, and effectively suppressing abnormal temperature rise. This further reduces the risk of faults caused by magnetic field distortion. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention 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 only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the inner core structure of the present invention; Figure 2 This is a top view of the inner core structure of the present invention; Figure 3 This is a schematic diagram of the internal structure of the inductor module of the present invention; Figure 4For the present invention Figure 3 A magnified schematic diagram of the structure at point A; Figure 5 This is a schematic diagram of the base structure of the present invention; Figure 6 For the present invention Figure 4 A magnified schematic diagram of the structure at point C; Figure 7 For the present invention Figure 3 A magnified schematic diagram of the structure at point B; Figure 8 This is a top view of the lead screw seat structure of the present invention; Figure 9 This is a top view of the magnetic guide assembly in the inserted state of the present invention.

[0020] In the diagram: 1. Three-dimensional coiled iron core; 2. Clamping piece; 3. Arc plate; 4. Support plate; 5. Center rod; 6. Insulating bracket; 7. Inductor module; 701. Coil; 702. Magnetic guide assembly; 703. Control mechanism; 704. Housing; 8. Fixed shaft; 9. End cap; 10. Reset assembly; 11. Guide wheel; 201. Magnetic guide sheet; 401. Housing; 402. Base; 301. Connector; 302. Guide rail assembly; 303. Drive assembly; 311. Base; 312. Groove; 321. Slide rail; 322. Sliding part; 331. Wedge; 332. Guide rod; 333. Spring; 334. Baffle; 335. Linear moving part; 3351. Lead screw seat; 3352. Transmission lead screw; 3353. Moving block; 1001. Base plate; 1002. Clamping plate. Detailed Implementation

[0021] 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.

[0022] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] This invention provides a short-circuit resistant oil-immersed three-dimensional wound core transformer, which, while improving the transformer's short-circuit resistance, also enables dynamic and smooth regulation of reactive power and harmonics. This achieves the integration of high reliability and proactive power quality management, and solves the problem that existing conventional oil-immersed transformers, due to their limited short-circuit resistance and lack of dynamic reactive power and harmonic regulation, cannot meet the dual requirements of high equipment reliability and proactive power quality management in modern complex power grids.

[0024] Please refer to this as well. Figures 1 to 9 The present invention provides a short-circuit resistant oil-immersed three-dimensional wound iron core transformer, which consists of a three-dimensional wound iron core 1, a high-voltage coil and a low-voltage coil, and is supported and connected by a clamp 2 and lead wires and other structures.

[0025] The low-voltage coil's winding insulation cylinder is made of high-strength epoxy glass fiber. The entire body is compressed by a fully pressurized arc-shaped plate 3 structure, achieving full contact with the upper and lower surfaces of the coil 701 to ensure uniform force distribution.

[0026] To further enhance overall mechanical strength, such as Figure 1 and Figure 2 As shown, support plates 4 are used to fill and tighten the space between the core window and the arc-shaped pressure plate, as well as between the core and the low-voltage coil insulation cylinder. The triangular area between the core and the coil 701 insulation cylinder is secured by inserting and fixing a specially made long cardboard piece. The iron triangular plate in the press-fit structure is reinforced by an extended round tube. Simultaneously, the upper and lower clamps 2 are equipped with positioning pins, and the final pressing of the transformer body is achieved by tightening the central rod 5 with a thread. These structural designs collectively ensure that the transformer body possesses extremely high short-circuit withstand capability.

[0027] Building upon the aforementioned high short-circuit withstand capability, to expand the transformer's application functions and enable it to dynamically adjust reactive power or suppress specific harmonics in complex power grid environments, thereby further improving power quality and system stability, this embodiment also includes an integrated inductor module 7. This module employs adjustable independent inductor units to achieve smooth and continuous inductance control while the transformer is energized. During operation, it dynamically and smoothly suppresses and compensates for system reactive power or specific harmonics, thereby improving the power quality and operational stability of the power grid.

[0028] Specifically, this transformer integrates the adjustable inductance module 7 inside the tank. Mechanically, the module body is securely fixed to a predetermined position on the inner wall of the tank cover via a high-strength insulating bracket 6, making it part of the transformer's internal load-bearing structure. Electrically, the module is led out through an independent sealed terminal block, which is installed parallel to the transformer's low-voltage side bushing on the tank cover and connected in parallel to the transformer's low-voltage side system circuit. This achieves plug-and-play functionality, providing the transformer with dynamic reactive power compensation or harmonic suppression capabilities while maintaining the original tank's sealing integrity and the reliability of the outgoing line insulation.

[0029] Specifically, such as Figure 1 , Figure 3 , Figure 4 , Figure 5As shown, the adjustable inductor module 7 in this embodiment achieves precise frequency control through mechanical structure adjustment. It mainly includes a coil 701, a magnetic conductor group 702, and a control mechanism 703. The coil 701 is wound axially and made of a metallic conductor material; its basic electromagnetic function is consistent with that of a conventional inductor. The magnetic conductor group 702, as the core component for adjusting the inductance, operates on a principle similar to a traditional magnetic core. The control mechanism 703 precisely controls the spatial position of the magnetic conductor group 702 relative to the coil 701, thereby changing the effective permeability of the magnetic circuit and achieving continuous adjustment of the inductance value.

[0030] In addition, such as Figure 1 , Figure 3 , Figure 4 , Figure 5 As shown, this embodiment also includes a complete housing 704 structure, within which the coil 701, the magnetic guide assembly 702, and the control mechanism 703 are all housed. The housing 704 is formed by the base 402 and the housing 401. The magnetic guide assembly 702 is arranged on one side of the coil 701 and consists of multiple magnetic guide sheets 201 equidistantly arranged along the axial direction of the coil 701. The number of magnetic guide sheets 201 corresponds to the number of turns of the coil 701. Each magnetic guide sheet 201 can be radially inserted into the corresponding turn on one side of the coil 701. By controlling the insertion depth, the effective cross-sectional area of ​​the magnetic material in the magnetic circuit can be changed, thereby achieving fine adjustment of the inductance.

[0031] Specifically, the magnetic sheet 201 has a unique tapered outer wall, with a smaller end closer to the coil 701 and a larger end further away. As the magnetic sheet 201 is pushed into the coil 701, the smaller end enters the inter-turn gap first. With increasing depth, the coupling area between the magnetic sheet 201 and the coil 701 gradually increases. This gradually changing cross-section allows for a smooth and continuous correspondence between changes in inductance and mechanical displacement, improving the linearity of adjustment and control precision.

[0032] like Figures 3-5As shown, the movement of the magnetic conductor 201 is controlled by the control mechanism 703, which mainly consists of three parts: a connector 301, a guide rail group 302, and a drive component 303. In this embodiment, the axially arranged magnetic conductors 201 can be divided into multiple independently controlled working groups. The number of magnetic conductors 201 in each group can be flexibly set according to actual adjustment needs and is not limited to a specific number. By controlling the radial insertion depth of each group of magnetic conductors 201 into the coil 701, not only can the coupling area between the magnetic conductor 201 and the coil 701 be continuously adjusted radially, but also, by controlling the insertion state of the magnetic conductors 201 in different axial sections, a step-like or combined adjustment of the total magnetic area in the axial direction can be achieved. Furthermore, through this radial and axial coordinated adjustment mechanism, its effect is similar to the traditional method of adjusting the inductance value by changing the axial insertion length of the magnetic core. However, thanks to the independent control of multiple groups of magnetic conductors 201, more precise and flexible inductance adjustment can be achieved, improving the control accuracy and adaptability of the equipment.

[0033] Specifically, such as Figures 3-7 As shown, the connector 301 is used to combine multiple magnetic sheets 201 together, enabling them to achieve precise radial displacement under the guidance of the guide rail assembly 302. Specifically, the connector 301 includes an L-shaped base 311 and a groove 312 formed at its lateral end. In this embodiment, the magnetic sheets 201 are arranged in groups of three along the axial direction. Each magnetic sheet 201 has a fixing hole at its larger end, into which a fixing shaft 8 is inserted. A reliable circumferential fixation and detachable connection are achieved through wedges 331 or screws. The larger ends of the three magnetic sheets 201 are placed together in the groove 312 of the base 311. The two side walls of the groove 312 are then connected to the two ends of the fixing shaft 8 by screws, thus integrating the three magnetic sheets 201 into a synchronous motion unit through a connector 301. When the connector 301 moves along the guide rail assembly 302, it can drive the entire group of magnetic sheets 201 to be inserted or pulled out synchronously along the radial direction of the coil 701, achieving coordinated adjustment of the inductance.

[0034] The guide rail assembly 302, serving as a guiding system, consists of a sliding part 322 and a slide rail 321. The base 311 is fixed to the top of the sliding part 322, while the slide rail 321 is mounted on the base 402 of the housing 704. Together, they form a high-precision linear motion mechanism. Through the tight fit between the slide rail 321 and the sliding part 322, the degree of freedom of the magnetic sheet 201 assembly during radial movement is effectively constrained, preventing offset and wobbling. This improves the accuracy of displacement and repeatability, ensuring the stability and reliability of the inductance adjustment process.

[0035] The drive assembly 303 achieves coordinated control of the radial insertion depth and axial position of the magnetic sheet 201 through a combination of rotation and linear motion. This significantly improves the precision and range of inductance adjustment by relying on dual-degree-of-freedom adjustment in both radial and axial directions. The drive assembly 303 mainly consists of a wedge 331, a guide rod 332, a spring 333, a baffle 334, and a linear moving part 335. The larger end of each magnetic sheet 201 is fixed to the outer wall of the base 311 with a guide rod 332. The baffle 334 is located on one side of the base 311 and fixed to the base 402 with bolts. The end of the guide rod 332 away from the magnetic sheet 201 slides out of the baffle 334, and its end is fixed with an end cap 9. A spring 333 is sleeved on the section of the guide rod 332 between the end cap 9 and the baffle 334, forming an elastic support system. This ensures that in the initial state, the smaller end of the magnetic sheet 201 is located to the side of the coil 701 and is not inserted into the coil 701. The wedge 331 is arranged on one side of the end cap 9 and is driven by the linear moving part 335 to reciprocate along the axial direction of the coil 701. When the wedge 331 contacts the end cap 9 of each group of guide rods 332 in sequence, the axial thrust is converted into the radial displacement of the guide rods 332 through the action of its inclined surface, thereby pushing each group of magnetic sheets 201 to be inserted into the coil 701 in sequence radially, so as to realize the precise graded adjustment of the inductance.

[0036] like Figures 6-8 As shown, the wedge 331 adopts a trapezoidal structure, with its end face along the moving direction machined into an inclined working surface. A rotatable guide wheel 11 is mounted at the end cap 9. When the wedge 331 moves axially along the coil 701, its inclined surface contacts the guide wheel 11, converting the axial movement of the wedge 331 into a radial thrust on the guide wheel 11, which in turn drives the magnetic sheet 201 to produce radial displacement. The guide wheel 11 converts sliding friction into rolling friction, effectively reducing motion resistance and wear, and improving the smoothness of adjustment and the durability of the mechanism.

[0037] Furthermore, to achieve a self-locking function during the adjustment process, the linear motion unit 335 employs a lead screw drive assembly for precision driving. For example... Figures 3-4 , Figures 6-8As shown, the transmission assembly consists of a lead screw seat 3351, a lead screw 3352, and a moving block 3353. The lead screw seat 3351 is fixed to the side wall of the housing 704, and the lead screw 3352 is installed in its internal cavity. The stroke of the lead screw covers the entire axial length of the magnetic conductor assembly 702. The moving block 3353 is threadedly engaged with the lead screw 3352 and is fixedly connected to the wedge block 331. When the knob at one end of the lead screw 3352 is rotated, the lead screw rotates, causing the moving block 3353 and the wedge block 331 to move axially, thereby pushing the magnetic sheet 201 to radially insert into the coil 701. Furthermore, utilizing the self-locking characteristic of the lead screw drive, the position of the wedge block 331 can be reliably maintained after adjustment, thereby stably maintaining the set inductance. One end of the lead screw 3352 extends to the outside of the housing 704 and is easily operated manually via a knob to achieve precise adjustment of the inductance.

[0038] It should be noted that in this embodiment, the other end of the transmission screw 3352 penetrates the transformer housing and extends to the external environment. A rotary dynamic seal structure is provided at this penetration point, which ensures that the transmission screw 3352 can rotate freely while strictly preventing leakage of the insulating oil inside the transformer and intrusion of external moisture, thus achieving both the adjustment function and the reliability of the oil tank seal.

[0039] Furthermore, in the adjustment mechanism where multiple sets of magnetic sheets 201 are sequentially radially inserted into the coil 701 via the inclined surface of the wedge block 331, the magnetic sheets 201 do not reach their maximum insertion depth synchronously. Instead, the adjustment stops when the system inductance reaches the target value. This results in different insertion depths for each set of magnetic sheets 201. Specifically, if the first set of magnetic sheets 201 has been fully inserted to its maximum depth within the coil 701 but the required inductance has not yet been achieved, the wedge block 331 needs to continue moving, thereby driving the second set of magnetic sheets 201 to begin inserting into the coil 701. If the second set of magnetic sheets 201 is partially inserted and has not yet reached its maximum depth, but the system inductance has already met the set value, the movement of the wedge block 331 stops. At this point, the first set of magnetic sheets 201 is at its maximum insertion depth, while the second set is only partially inserted. The actual insertion depth of the two sets of magnetic sheets 201 in the coil 701 will differ, resulting in an uneven coupling distribution both axially and radially. This uneven working state may lead to various potential malfunctions.

[0040] From an electromagnetic performance perspective, inconsistent insertion depths will result in uneven magnetic field distribution within coil 701. The magnetic flux density around the deeper inserted magnetic sheet 201 will be significantly higher than that in the shallower areas. This magnetic field distortion will not only reduce the control accuracy of the inductance but may also cause localized overheating, accelerating insulation aging and affecting system efficiency and stability. At the mechanical structure level, the electromagnetic reaction forces experienced by the magnetic sheets 201 at different depths also differ.

[0041] To ensure that each group of magnetic sheets 201 maintains a uniform insertion depth in the coil 701 and to avoid asymmetrical operation caused by segmented adjustment, such as Figure 3 , Figure 4 , Figure 6 and Figure 7 As shown, this embodiment adds a reset assembly 10. The core of the reset assembly 10 lies in the use of the bidirectional inclined surface of the wedge 331 and the linkage clamping plate 1002 mechanism to realize the synchronous reset and cooperative insertion of the magnetic sheet 201 group. Specifically, the wedge 331 is designed as a trapezoidal structure, and both end faces along the axial direction of the coil 701 are machined into symmetrical inclined surfaces, and the overall length of the wedge 331 is less than the distance between two adjacent guide wheels 11. The reset assembly 10 is mainly composed of a base plate 1001 and a clamping plate 1002; a base plate 1001 is fixedly sleeved at the end cap 9 of each guide rod 332, and a spring 333 is set between the base plate 1001 and the baffle 334 to provide reset elasticity; a clamping plate 1002 is fixed on the side of each base plate 1001 facing the lead screw seat 3351, and the length of the clamping plate 1002 is greater than the distance between two adjacent base plates 1001, so that one end is fixed on its own base plate 1001, and the other end overlaps the side surface of the adjacent base plate 1001.

[0042] With reference to the maximum position end (all magnetic sheets 201 inserted) and the minimum position end (all not inserted) of the coil 701 axial direction, the arrangement sequence of the clamping plate 1002 is as follows: the clamping plate 1002 located on the base plate 1001 of the guide rod 332 at the maximum position end, with its free end abutting against the side of the base plate 1001 of the previous guide rod 332, and so on, passing towards the minimum position end. When the wedge block 331 starts to move from the minimum position end, its inclined surface first contacts and pushes the guide wheel 11 of the first group of magnetic sheets 201, so that the group of magnetic sheets 201 is radially inserted into the coil 701; if the inductance is still not up to standard at this time, the wedge block 331 continues to move, and when its other inclined surface contacts the guide wheel 11, the first group of magnetic sheets 201 begins to reset and retract under the action of the spring 333. Since the length of the wedge 331 is less than the spacing between the guide wheels 11, when the wedge 331 moves between the two sets of guide wheels 11, the first set of magnetic plates 201 is fully reset to its initial position by the reset action of the spring 333.

[0043] Subsequently, wedge 331 contacts the guide wheel 11 of the second set of magnetic sheets 201 and pushes it to move radially. At this time, the substrate 1001 of the second set of magnetic sheets 201 pushes the substrate 1001 of the first set of magnetic sheets 201 through the clamping plate 1002, causing the two sets of magnetic sheets 201 to be inserted radially into the coil 701 simultaneously. Through this mechanism, each time a new set of magnetic sheets 201 is introduced, the previously operated groups will first reset and then participate in the movement synchronously, thereby ensuring that all the magnetic sheets 201 participating in the operation have a consistent insertion depth at any termination time, fundamentally eliminating the problem of uneven depth caused by group operation, and improving the stability and reliability of inductor adjustment.

[0044] To ensure that the multiple sets of magnetic sheets 201 maintain synchronous movement during adjustment and avoid uneven insertion depth caused by segmented movements, this embodiment achieves linkage and reset between the sets through the directional arrangement of the clamping plate 1002. Specifically, when the base plate 1001 of the second set of magnetic sheets 201 moves, since the clamping plate 1002 of the third set is located on the side facing the lead screw seat 3351 (i.e., the opposite side of the insertion direction of the magnetic sheet 201), the movement of the second set will not push the third set, thus ensuring the stationary state of the inactive set. When the target inductance is not reached after the second set of magnetic sheets 201 is inserted, the wedge block 331 continues to move between the guide wheels 11 of the second and third sets. At this time, the second set and the linked first set are synchronously reset to the initial position under the action of the spring 333. Subsequently, wedge 331 pushes the third set of guide wheels 11, causing them to move along the insertion direction. The third set, through its locking plate 1002, drives the second set of substrates 1001. The second set, in turn, drives the first set through its own locking plate 1002, forming the synchronous radial insertion of the first three sets of magnetic sheets 201. Figure 9 As shown, this ensures that all the magnetic sheets 201 involved in the operation can enter the coil 701 at the same depth during any adjustment stage, avoiding faults such as magnetic field distortion, local overheating or mechanical stress concentration caused by differences in insertion depth, and improving the stability and reliability of inductance adjustment.

[0045] In this embodiment, when adjusting the inductance: First, in the initial state, all magnetic plates 201 are positioned outside the radial direction of the coil 701 under the action of the return spring 333, at which point the inductor exhibits its basic inductance value. When it is necessary to increase the inductance, the rotary knob drives the lead screw to rotate, causing the wedge 331 to move axially along the coil 701. The inclined surface of the wedge 331 first contacts the guide wheel 11 of the first group of magnetic plates 201, pushing them radially into the turns of the coil 701. The inductance is continuously fine-tuned by gradually increasing the cross-sectional area of ​​the tapered magnetic plates 201. If the first group of magnetic plates 201 reaches the maximum insertion depth but still does not meet the requirements, the wedge 331 is driven to continue moving. The inclined surface of the wedge block 331 contacts the second set of guide wheels 11. At this time, the other inclined surface of the wedge block 331 will push the first set of magnetic plates 201 to compress the spring 333 and reset and exit. When the wedge block 331 is completely moved to the second set of working positions, the first set has been completely reset and the second set begins to be inserted. At the same time, the clamping plate 1002 of the second set of magnetic plates 201 will drive the base plate 1001 of the first set, so that the two sets of magnetic plates 201 are inserted radially in sync. The adjustment of subsequent sets is carried out in the same way to ensure that the insertion depth of all magnetic plates 201 involved in the work is consistent at any time, thereby realizing the coordinated fine adjustment of inductance in axial distribution and radial depth, and maintaining the set position through the self-locking characteristic of the lead screw.

[0046] It should be noted that in this specification, relational terms such as first and second are used only to distinguish one entity from several other entities, and do not necessarily require or imply any such actual relationship or order between these entities.

[0047] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. It should be noted that those skilled in the art can make several improvements and modifications to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the protection scope of the present invention.

Claims

1. A short-circuit resistant oil-immersed three-dimensional wound core transformer, comprising a three-dimensional wound core (1), a transformer body composed of high-voltage coils and low-voltage coils, and clamps (2) for support and connection, characterized in that: The body is pressed by a fully pressurized arc plate, and support plates (4) are filled between the core window and the arc plate, and between the core and the insulating cylinder of the low-voltage coil to enhance the overall mechanical strength; the body is finally pressed by a threaded central rod (5); The transformer also includes an inductor module (7) integrated inside its tank via an insulating support (6), which is led out through an independent sealed terminal block and connected in parallel to the low-voltage side circuit of the transformer. The inductor module (7) is configured to achieve smooth and continuous adjustment of the module inductance by means of radial displacement of multiple sets of magnetic conductors (702) arranged axially inside it relative to the coil (701).

2. The short-circuit resistant oil-immersed three-dimensional wound core transformer according to claim 1, characterized in that, The inductor module (7) includes a housing (401), a base (402), a coil (701) disposed in the housing (401), and a magnetic guide assembly (702) and a control mechanism (703) for adjusting the inductance. The magnetic guide assembly (702) is composed of several magnetic guide sheets (201) arranged along the axial direction of the coil (701). The magnetic guide sheet (201) has a tapered outer wall, with the end near the coil (701) being the small end and the end away from the coil (701) being the large end. The control mechanism (703) includes a drive assembly (303) that can drive the magnetic guide sheet (201) to move radially along the coil (701) to change the effective area of ​​the tapered outer wall of the magnetic guide sheet (201) extending into the turns of the coil (701).

3. A short-circuit resistant oil-immersed three-dimensional wound core transformer according to claim 2, characterized in that, The drive assembly (303) includes a linear moving part (335), a wedge (331) driven by the linear moving part (335) to move axially, and a guide rod (332) driven by the inclined surface of the wedge (331) to move radially. The guide rod (332) is connected to the large end of the magnetic sheet (201). Both ends of the wedge (331) along its moving direction are set as symmetrical inclined surfaces.

4. A short-circuit resistant oil-immersed three-dimensional wound core transformer according to claim 3, characterized in that, The end of the guide rod (332) is rotatably mounted with a guide wheel (11), which is in contact with the inclined surface of the wedge (331).

5. A short-circuit resistant oil-immersed three-dimensional wound core transformer according to claim 3, characterized in that, The linear drive unit is a lead screw drive assembly, including a lead screw (3352) and a moving block (3353) fixed to the wedge (331), wherein the moving block (3353) is threadedly engaged with the lead screw (3352).

6. A short-circuit resistant oil-immersed three-dimensional wound core transformer according to claim 3, characterized in that, It also includes a reset assembly (10), which includes a base plate (1001) fixed on each guide rod (332) and a retaining plate (1002) fixed to the side of the base plate (1001); the free end of the retaining plate (1002) overlaps the side of the base plate (1001) of the adjacent guide rod (332); when a group of guide rods (332) is driven by wedges (331) to move radially, its base plate (1001) pushes the adjacent base plate (1001) through the retaining plate (1002), thereby driving all the reset magnetic sheets (201) groups to move synchronously.

7. A short-circuit resistant oil-immersed three-dimensional wound core transformer according to claim 6, characterized in that, The guide rod (332) slides through the baffle (334), the baffle (334) is fixed on the base (402), and a spring (333) is sleeved on the rod segment of the guide rod (332) between the baffle (334) and the base plate (1001). The two ends of the spring (333) abut against the baffle (334) and the base plate (1001) respectively, providing a restoring force for the guide rod (332).

8. A short-circuit resistant oil-immersed three-dimensional wound core transformer according to claim 3, characterized in that, The overall length of the wedge (331) is less than the distance between the guide wheels (11) on the two adjacent guide rods (332), so that the wedge (331) can move between the two sets of guide wheels (11) to provide a reset space for the working magnetic sheet (201) group.

9. A short-circuit resistant oil-immersed three-dimensional wound core transformer according to claim 2, characterized in that, The magnetic conductive sheets (201) are arranged in groups by connectors (301). The connectors (301) include an L-shaped base (311) and a groove (312). The large end of the magnetic conductive sheet (201) is installed in the groove (312) by a fixed shaft (8), so that multiple magnetic conductive sheets (201) form a synchronous motion unit.

10. A short-circuit resistant oil-immersed three-dimensional wound core transformer according to claim 5, characterized in that, One end of the drive screw (3352) extends to the outside of the transformer housing (704).

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