Progressive skewback structure of transformer

Abstract

The utility model discloses a kind of progressive inclined slot pull plate structures of transformer, including pull plate main body, on the pull plate main body, there is slotted portion, each slotted portion has multiple slotted groups, each slotted group has multiple parallelly arranged slots;The inclination angle of slot in each slotted group relative to the Y central axis of the pull plate main body, along the Y central axis direction of the pull plate main body, from the center of the pull plate main body to both ends, gradient decreases, Y central axis is parallel with the long side of the pull plate main body;The width of slot in each slotted group from the center of the pull plate main body to both ends, gradient decreases, the pitch of adjacent two slots in each slotted group from the center of the pull plate main body to both ends, gradient increases.The slot in the utility model is designed by inclination angle, slot width, pitch triple gradient, can reduce eddy current loss, enhance the heat dissipation effect and bending strength of pull plate main body.

Description

Technical Field

[0001] This utility model relates to the technical field of transformers, and in particular to a progressive inclined slot pull plate structure for a transformer. Background Technology

[0002] The transformer's tie plate is fastened to the upper and lower clamps via pins, providing fixation and support to the transformer and preventing displacement or loosening of the core during operation. During transformer operation, because the tie plate is very close to the core, leakage flux is relatively large, easily leading to increased local eddy current losses and local overheating, thus affecting the transformer's operating efficiency. To address this problem, two common solutions are generally used: (1) changing the tie plate material to non-magnetic steel; (2) cutting a certain number of straight slots on the tie plate. Both of these methods are effective in reducing eddy current losses and local overheating in the tie plate at 50Hz or 60Hz power frequencies.

[0003] However, with increasing frequency and the complexity of transformer operating conditions, such as in high-frequency transformers or those containing a large number of high-order harmonics, the hysteresis and eddy current losses in the metal steel components and silicon steel sheets increase significantly due to the higher frequency and the injection of high-order harmonics. To address this, adding straight slots to the tie plate or using non-magnetic steel materials weakens the reduction effect on losses and localized overheating. Therefore, in high-frequency transformers or operating conditions containing a large number of high-order harmonics, neither adding straight slots to the tie plate nor using non-magnetic steel materials can effectively solve the problems of excessive eddy current losses and localized overheating in the tie plate. Utility Model Content

[0004] In order to overcome the above-mentioned technical defects, the present invention provides a progressive inclined slot pull plate structure for a transformer, which aims to solve at least one of the problems in the background art.

[0005] This utility model is implemented according to the following technical solution:

[0006] This utility model discloses a progressive inclined slot puller structure for a transformer, including a puller body. On the puller body, slotted portions are centrally symmetrically distributed. Each slotted portion has multiple slot groups, and each slot group has multiple parallel slots. The inclination angle of the slots in each slot group relative to the Y-axis of the puller body decreases gradually from the center of the puller body towards both ends along the Y-axis direction. The Y-axis is parallel to the long side of the puller body. The width of the slots in each slot group decreases gradually from the center of the puller body towards both ends, and the spacing between adjacent slots in each slot group increases gradually from the center of the puller body towards both ends.

[0007] Compared with existing technologies, the slotting in this invention, through a triple gradient design of tilt angle, slot width, and spacing, can alter the eddy current path, segmenting and blocking the originally continuous eddy current path. This avoids local eddy current concentration, significantly improves eddy current distribution, and reduces eddy current loss. The gradient-designed slotting achieves uniform eddy current blocking across the entire plate body, suppressing eddy current saturation and greatly blocking leakage magnetic paths. Simultaneously, the slotting forms a uniform heat dissipation path, increases the contact area with air, and enhances the heat dissipation effect of the plate body. The gradual angle of the slotting disperses stress concentration, improves the bending strength of the plate body, and prevents crack propagation under processing or short-circuit electrodynamics.

[0008] In a preferred embodiment, from the end of the pull plate body to the center, the slotted portion sequentially includes a first slotting group, a second slotting group, and a third slotting group; the length range occupied by the first slotting group, the second slotting group, and the third slotting group is 1 / 8 of the length of the pull plate body, and sequentially constitutes region A, region B, and region C.

[0009] In a preferred embodiment, the inclination angle of the slots in the first slotting group is 30°, the slot width is 2-3 mm, and the slot spacing is 15-20 mm.

[0010] In a preferred embodiment, the inclination angle of the grooves in the second grooving group is 45°, the groove width is 3-4 mm, and the groove spacing is 12-15 mm.

[0011] In a preferred embodiment, the inclination angle of the grooves in the third grooving group is 60°, the groove width is 4-5mm, and the groove spacing is 10-12mm.

[0012] In a preferred embodiment, the thickness of the pull plate body includes the groove depth and the substrate thickness, wherein the ratio of the groove depth to the substrate thickness is 4:1.

[0013] In a preferred embodiment, the transformer pull plate shown is connected to the upper and lower clamps of the transformer by means of pins.

[0014] In a preferred embodiment, the pull plate body and the pin are connected by welding.

[0015] In a preferred embodiment, both the pull plate body and the pin are made of non-magnetic steel.

[0016] In a preferred embodiment, the pull plate body is arranged symmetrically with respect to the plane of symmetry of the transformer leakage flux. Attached Figure Description

[0017] The specific embodiments of this utility model will be further described in detail below with reference to the accompanying drawings, wherein:

[0018] Fig. 1 This is a front view schematic diagram of the transformer pull plate body and pin of this utility model;

[0019] Fig. 2 This is a side view of the transformer pull plate body and pin of this utility model;

[0020] Fig. 3 This is a front view schematic diagram of the connection between the transformer core, upper clamp, lower clamp, and pull plate body of this utility model;

[0021] Fig. 4 This is a three-dimensional schematic diagram of the connection between the transformer core, upper clamp, lower clamp, and pull plate of this utility model.

[0022] Explanation of reference numerals in the attached figures:

[0023] 1-Pin, 2-Pulley body, 201-First slotted group, 202-Second slotted group, 203-Third slotted group, 3-Upper clamp, 4-Lower clamp, 5-Iron core. Detailed Implementation

[0024] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0025] To better illustrate this utility model, a further detailed description of this utility model is provided below with reference to the accompanying drawings.

[0026] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to limit the embodiments of this application. The singular forms “a,” “the,” and “the” used in the embodiments of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0027] See Figs. 1 to 4This utility model discloses a progressive inclined slot puller structure for a transformer, including a puller body 2. On the puller body 2, slotted portions are centrally symmetrically distributed. Each slotted portion has multiple slot groups, and each slot group has multiple parallel slots. The inclination angle of the slots in each slot group relative to the Y-axis of the puller body decreases gradually from the center of the puller body 2 towards both ends along the Y-axis direction. The Y-axis is parallel to the long side of the puller body 2. The width of the slots in each slot group decreases gradually from the center of the puller body 2 towards both ends, and the spacing between adjacent slots in each slot group increases gradually from the center of the puller body 2 towards both ends.

[0028] Compared with the prior art, the slotting in this utility model, through a triple gradient design of tilt angle, slot width, and spacing, can change the eddy current path, segmenting and blocking the originally continuous eddy current path, avoiding local eddy current concentration, significantly improving the eddy current distribution, and reducing eddy current loss. The gradient-designed slotting can achieve uniform eddy current blocking throughout the entire pull plate body 2, suppressing eddy current saturation and greatly blocking the leakage magnetic path. At the same time, the slotting forms a uniform heat dissipation path and increases the contact area with air, enhancing the heat dissipation effect of the pull plate body 2. The gradual angle of the slotting disperses stress concentration, improves the bending strength of the pull plate body 2, and avoids crack propagation under processing or short-circuit electrodynamics.

[0029] Specifically, the central region of the pull plate body 2 is a region of strong leakage magnetic flux with a long eddy current loop. Large-angle wide slots and denser slotting can be used to enhance the blocking effect and improve the eddy current suppression rate. Conversely, the ends of the pull plate body 2 are regions of weak leakage magnetic flux with short eddy current loops. Small-angle narrow slots can be used for blocking. The slotting specifications and angles in the middle section are progressively matched to those in the central and end regions. This progressive matching satisfies the spatial distribution of leakage magnetic flux, avoids local eddy current saturation, and disperses stress concentration.

[0030] Furthermore, from the end of the pull plate body 2 to the center, the slotted portion sequentially includes a first slotting group 201, a second slotting group 202, and a third slotting group 203; the length range occupied by the first slotting group, the second slotting group, and the third slotting group is 1 / 8 of the length of the pull plate body 2, and they sequentially form region A, region B, and region C, and are grouped into equal length groups, that is, the length range occupied by each slotted portion is 3 / 8 of the length of the pull plate body 2. Since the slotted portions are centrally symmetrically arranged, the total length range occupied by the slotted portions is 6 / 8 of the length of the pull plate body 2, and the remaining 2 / 8 of the length of the pull plate body 2 is used to provide space for welding pins 1.

[0031] Furthermore, the inclination angle of the slots in the first slotting group 201 is 30°, the slot width d201 is 2-3 mm, and the slot spacing d201-1 is 15-20 mm.

[0032] Furthermore, the inclination angle of the slots in the second slotting group 202 is 45°, the slot width d202 is 3-4 mm, and the slot spacing d202-1 is 12-15 mm.

[0033] Furthermore, the inclination angle of the slots in the third slotting group 203 is 60°, the slot width d201 is 4-5mm, and the slot spacing d203-1 is 10-12mm.

[0034] In one embodiment, the thickness d of the pull plate body 2 includes the groove depth d1 and the base material retention thickness d2, i.e., d = d1 + d2, wherein the ratio of the groove depth d1 to the base material retention thickness d2 is 4:1. This is mainly to ensure the mechanical strength of the pull plate body 2, improve the bending resistance, prevent the pull plate body 2 from breaking, and avoid cracks or crack propagation under processing and short circuit forces.

[0035] In one embodiment, the transformer pull plate is connected to the upper clamp 3 and lower clamp 4 of the transformer via a pin 1. Using a pin 1 instead of a traditional bolt connection simplifies the assembly process, reduces the complexity of threaded connections, and avoids the risk of connection failure due to loose bolts.

[0036] Furthermore, the pull plate body 2 and the pin 1 are connected by welding. Welding makes the pin 1 and the pull plate body 2 form an integrated metal bond, avoiding the risk of loosening or falling off due to vibration, temperature changes or long-term load after the traditional pin 1 is inserted, and significantly improving the shear and tensile strength of the connection structure.

[0037] Furthermore, both the pull plate body 2 and the pin 1 are made of non-magnetic steel. Non-magnetic steel does not conduct magnetism, avoiding the material's own magnetization or the influence of external magnetic fields, ensuring that the geometric parameters of the slotted structure (such as tilt angle, slot width, and spacing) are not affected by the magnetic field, and maintaining the intended magnetic flux distribution and eddy current suppression effect.

[0038] In one embodiment, the pull plate body 2 is symmetrically arranged with respect to the symmetrical plane of the transformer leakage flux, so that the tensile / repulsive forces of the leakage flux on both sides of the pull plate body 2 are balanced, reducing the mechanical stress concentration caused by magnetic field asymmetry and preventing the pull plate from deforming or fatigue-breaking. Combined with the gradient design of the slotted structure's tilt angle, width, and spacing, the pull plate body 2, symmetrically arranged with the transformer leakage flux, can more evenly divide the leakage flux, avoiding localized high losses caused by unilateral flux concentration and further improving energy efficiency.

[0039] It should be noted that the magnetic flux within the iron core region is called the main magnetic flux, while the magnetic flux distributed outside the iron core region is called the leakage magnetic flux.

[0040] Based on the disclosure and teachings of the above specification, those skilled in the art can make changes and modifications to the above embodiments. Therefore, this utility model is not limited to the specific embodiments disclosed and described above, and some modifications and changes to this utility model should also fall within the protection scope of the claims of this utility model. Furthermore, although some specific terms are used in this specification, these terms are only for convenience of explanation and do not constitute any limitation on this utility model.

Claims

1. A progressive inclined slot pull plate structure for a transformer, comprising a pull plate body, characterized in that, On the main body of the pull plate, slotted portions are centrally symmetrically distributed. Each slotted portion has multiple slot groups, and each slot group has multiple parallel slots. The inclination angle of the slots in each slot group relative to the Y-axis of the main body of the pull plate decreases gradually from the center of the main body towards both ends along the Y-axis of the main body of the pull plate. The Y-axis is parallel to the long side of the main body of the pull plate. The width of the slots in each slot group decreases gradually from the center of the main body towards both ends. The spacing between two adjacent slots in each slot group increases gradually from the center of the main body towards both ends.

2. The progressive inclined slot plate structure of the transformer according to claim 1, characterized in that: The slotted portion includes, in sequence, a first slotted group, a second slotted group, and a third slotted group; The length range occupied by the first slotting group, the second slotting group and the third slotting group is 1 / 8 of the length of the main body of the pull plate, and they form region A, region B and region C respectively.

3. The progressive inclined slot plate structure of the transformer according to claim 2, characterized in that: In the first grooving group, the grooving inclination angle is 30°, the grooving width (d201) is 2-3 mm, and the grooving spacing (d201-1) is 15-20 mm.

4. The progressive inclined slot pull plate structure of the transformer according to claim 3, characterized in that: In the second grooving group, the grooving inclination angle is 45°, the grooving width (d202) is 3-4 mm, and the grooving spacing (d202-1) is 12-15 mm.

5. The progressive inclined slot pull plate structure of the transformer according to claim 4, characterized in that: The inclination angle of the grooves in the third grooving group is 60°, the groove width (d203) is 4-5 mm, and the groove spacing (d203-1) is 10-12 mm.

6. The progressive inclined slot plate structure of the transformer according to claim 1, characterized in that: The thickness (d) of the main body of the pull plate includes the groove depth (d1) and the base material thickness (d2), wherein the ratio of the groove depth (d1) to the base material thickness (d2) is 4:

1.

7. The progressive inclined slot plate structure of the transformer according to claim 1, characterized in that: The transformer pull plate shown is connected to the upper and lower clamps of the transformer by pins.

8. The progressive inclined slot plate structure of the transformer according to claim 7, characterized in that: The pull plate body and the pin are connected by welding.

9. The progressive inclined slot pull plate structure of the transformer according to claim 7 or 8, characterized in that: Both the pull plate body and the pin are made of non-magnetic steel.

10. The progressive inclined slot pull plate structure of the transformer according to claim 1, characterized in that: The main body of the pull plate is arranged symmetrically with respect to the plane of the transformer leakage flux.

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