Three-dimensional wound core winding die and winding method

Abstract

The invention discloses a three-dimensional wound core winding die and a winding method. The three-dimensional wound core winding die comprises an outer frame and two oppositely-arranged supporting plates connected with the outer frame in a clamped mode, fixing grooves matched with a first winding platform or a second winding platform are formed in the two supporting plates, and a connecting and fixing mechanism is arranged between the two supporting plates; by adopting the winding die structure of the separable outer frame and the support plate, the stress structure change of the iron core caused by the separation of the support plate and the reinstallation process during the measurement of the magnetic characteristics of the inner ring iron core is effectively prevented, and the winding efficiency and quality of the iron core are improved; and secondly, by adopting the mode of combining the two winding platforms and the winding die with high adaptability, the problems that parameters such as winding speed and tension need to be adjusted frequently due to different strip materials, and material strips and the winding die need to be replaced frequently are solved, and the production efficiency is improved.

Description

Technical Field

[0001] The invention relates to a three-dimensional wound core, and in particular to a three-dimensional wound core winding mold and a winding method. Background Art

[0002] Traditional distribution transformers can be divided into amorphous alloy transformers and silicon steel transformers according to the core materials. The hybrid magnetic circuit three-dimensional wound core distribution transformer combines the advantages of these two materials. Its core is made of silicon steel sheets or amorphous alloy materials and is formed through a specific winding process. In the prior art, there are a series of problems in the winding method of the single-frame hybrid magnetic circuit three-dimensional wound core. One is to process amorphous materials and silicon steel materials on the same core winding machine. However, due to the difference in material properties, it is necessary to frequently adjust parameters such as winding speed and tension, and it is also necessary to frequently replace the material strip, which greatly reduces the work efficiency. When measuring the magnetic properties of the inner core, the winding mold needs to be disassembled; and when winding the outer core, the winding mold needs to be reinstalled. This disassembly and assembly process is not only cumbersome, but also may cause changes in the stress structure of the inner core, thereby affecting the magnetic properties of the core. The other is to first wind the two materials separately for annealing, and then fit the cores of the two materials together to form a whole. Due to the low adaptability of the existing winding mold, two sizes of molds, inner and outer, are required when winding separately and then assembling. If the tolerance of the strip design is large, the gap between the inner and outer cores will be large, which will cause the iron loss of the hybrid core to increase, and affect the overall performance of the single-frame core of the hybrid three-dimensional core. If the design tolerance is small, it is difficult to fit the inner and outer cores together. These problems seriously restrict the winding efficiency and quality of the core. Summary of the invention

[0003] Purpose of the invention: The purpose of the present invention is to provide a winding mold that can significantly improve the winding efficiency and quality of a hybrid iron core; another purpose of the present invention is to provide a method for winding a three-dimensional iron core using the winding mold.

[0004] Technical solution: The three-dimensional iron core winding mold described in the present invention includes an outer frame and two support plates that are relatively spaced apart and clamped with the outer frame. The two support plates are provided with fixing grooves that match the first winding platform or the second winding platform, and a connecting and fixing mechanism is provided between the two support plates.

[0005] Preferably, the connection and fixing mechanism comprises a connection groove on the support plate and a tensioning member.

[0006] Preferably, the number of the connecting grooves is two or more.

[0007] Preferably, the tensioning member is a strapping belt or a tensioning bolt matched with the connecting groove.

[0008] Preferably, the two support plates are spaced and limited by a protrusion in the middle of the outer frame.

[0009] Preferably, the corners of the outer frame and the support plate are rounded arcs, so as to reduce stress concentration, increase structural strength and improve electromagnetic performance, thereby improving the overall performance and reliability of the transformer, and the surface of the support plate is provided with a wear-resistant coating to enhance its durability.

[0010] The method for winding a three-dimensionally wound core using the winding mold described in the present invention comprises the following steps:

[0011] Before the overall winding operation or the winding operation of a single winding platform, the inner ring core strip and the outer ring core strip are cut into sections according to the hybrid core design plan and the cutting table data information for spare use;

[0012] S1: Install a winding die on the first winding platform, wind the inner ring core strip, remove the single frame inner ring core after winding, remove the support plate, repeat twice, and complete three single frame inner ring cores for standby use;

[0013] S2: Assemble three single-frame inner ring cores into a combined inner ring core and perform annealing to avoid the influence of single-frame annealing on the core shape;

[0014] S3: Split the qualified combined inner core into single frame inner cores, install the support plate and send them to the second winding platform, wind the outer core strip, remove the single frame mixed core after winding, remove the support plate, repeat twice, and complete three single frame mixed cores for standby;

[0015] S4: Assemble the three single-frame hybrid cores into a combined hybrid core and perform secondary annealing, apply glue to finalize the core, and inspect whether it is qualified.

[0016] Preferably, the inner ring core strip is made of silicon steel strip, and the outer ring core strip is made of amorphous alloy strip.

[0017] Preferably, the annealing temperature in step S2 is 720-800° C., and the annealing time is 3-4 hours. The secondary annealing temperature in step S4 is 320-400° C., and the annealing time is 3-4 hours.

[0018] Preferably, the step S4 adopts a glass glue curing and shaping process, which can significantly improve its insulation performance, corrosion resistance, bonding strength and long-term stability.

[0019] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages: by adopting a winding mold structure with a detachable outer frame and a support plate, the stress structure change of the core caused by the detachment from the support plate and the reinstallation process when measuring the magnetic properties of the inner ring core is effectively prevented, thereby improving the winding efficiency and quality of the core; secondly, by adopting a combination of two winding platforms and a highly adaptable winding mold, the frequent adjustment of parameters such as winding speed and tension due to different strip materials, as well as the frequent replacement of material strips and winding molds, are avoided, thereby improving production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the winding mold in the present invention.

[0021] Figure 2 It is a schematic diagram of the winding mold structure in the present invention.

[0022] Figure 3 It is a winding flow chart of the three-dimensional wound core in the present invention.

[0023] Figure 4 It is a schematic diagram of the winding of the single frame inner ring core in the present invention.

[0024] Figure 5 It is a schematic diagram of the winding of the combined inner ring core in the present invention.

[0025] Figure 6 It is a schematic diagram of the winding of the single frame outer ring core in the present invention.

[0026] Figure 7 It is a schematic diagram of the winding of the combined outer ring core in the present invention. DETAILED DESCRIPTION

[0027] The technical solution of the present invention is further described below in conjunction with the accompanying drawings.

[0028] like Figure 1-7As shown, this embodiment provides a winding mold, which consists of an outer frame 1 and two support plates 2 that are arranged opposite to each other and are clamped to the outer frame 1. The inner wall of the outer frame 1 is provided with a circle of protrusions, and the cross section is convex. The outline size of the support plate 2 matches the inner outline of the outer frame 1 and can be clamped on both sides of the protrusions of the outer frame 1 and restricted by the protrusions, which is used to support the outer frame 1 so that it does not deform, and also serves as a connecting piece between the outer frame 1 and the reel on the winding platform. A fixing groove 4 is provided on the support plate 2, and the fixing groove 4 matches the first winding platform and the second winding platform. The winding mold can be installed on any winding platform to meet the winding requirements of different strips. In order to maintain the stability of the support plate 2, a plurality of connecting grooves 3 are provided on the support plate 2, and the two opposite support plates 2 are tightened through the connecting grooves 3 using mounting straps or tension bolts, so that the two support plates 2 and the outer frame 1 form a stable whole. At the same time, the corners of the outer frame 1 and the support plate 2 are rounded arcs, thereby reducing stress concentration, increasing structural strength and improving electromagnetic performance, and improving the overall performance and reliability of the transformer. The surface of the support plate 2 is provided with a wear-resistant coating to enhance its durability.

[0029] The entire three-dimensional core winding process is as follows: due to the different hardness and brittleness of silicon steel and amorphous materials, the winding parameters are different. It is now necessary to wind silicon steel and amorphous materials on the first platform and the second platform respectively. By controlling the tension of the strip and the compression force of the core winding strip, the requirements of tight and flat strip winding are achieved; the two support plates 2 and the outer frame 1 are fixed by strapping.

[0030] Taking the 50kVA hybrid magnetic circuit three-dimensional coil as an example, the strip is first sheared according to the cutting variable. The cutting table is as follows. It is divided into 7 sections, among which sections 1 to 3 are oriented silicon steel, and sections 4 to 7 are amorphous alloys.

[0031] Cutting table

[0032]

[0033] Install the winding mold on the first winding platform and start winding the silicon steel core until the winding of the section 3 strip is completed. Take the single-frame silicon steel core from the first winding platform, remove the support plate 2 in the winding mold and place it on the assembly platform for standby. Repeat the winding of the other two single-frame silicon steel cores. Use a detachable fixed tooling to assemble three single-frame silicon steel cores on the assembly platform.

[0034] According to the annealing process requirements, the assembled silicon steel core is sent to the annealing furnace for annealing. The annealing process is carried out according to the annealing requirements of silicon steel. The annealing temperature is 720-800℃ and the annealing time is 3-4 hours. The performance test of the silicon steel core after annealing is carried out. A three-phase excitation voltage is applied to the core column. The data is calculated based on the loss curve of the inner core material. The excitation turn voltage U1=1.604V, and the test no-load loss P1 is less than 29.5W, which meets the requirements, that is, the core is judged to be qualified.

[0035] The silicon steel core that has passed the test is split into three single-frame silicon steel cores, and after installing the support plate 2, it is sent to the second winding platform, and the amorphous strip is introduced and the winding begins until the winding of the amorphous strip is completed. The single-frame hybrid core is taken out from the second winding platform, and after removing the support plate 2, it is placed on the assembly platform for standby. The winding of the other two single-frame hybrid cores is completed. The three single-frame hybrid cores are assembled on the assembly platform using a detachable fixed tooling.

[0036] According to the annealing process requirements, the assembled hybrid core is sent to the annealing furnace for secondary annealing. The annealing is required to be carried out according to the amorphous annealing process. The secondary annealing temperature is 320-400°C and the annealing time is 3-4h.

[0037] After annealing, the core is cured by epoxy resin glue and then tested for performance. A three-phase excitation voltage is applied to the core column so that the magnetic flux density of the inner frame core is under the rated working magnetic flux density, and the turn voltage U2 = 5.132V. The no-load loss P2 is less than 60W, which meets the requirement of reducing the no-load loss of the first-level energy-efficient silicon steel transformer of the same capacity by more than 15% as specified in GB20052-2024. The hybrid core is considered qualified.

Claims

1. A three-dimensional coiled core winding die, characterized in that: The invention comprises an outer frame (1), two support plates (2) which are arranged at a distance from each other and are clamped to the outer frame (1), the two support plates (2) are provided with fixing grooves (4) which match the first winding platform or the second winding platform, and a connecting fixing mechanism is provided between the two support plates (2).

2. The winding die according to claim 1, characterized in that: The connection and fixing mechanism comprises a connection groove (3) on the support plate (2) and a tensioning member.

3. The winding die according to claim 2, characterized in that: The number of the connecting grooves (3) is two or more.

4. The winding die according to claim 2, characterized in that: The tensioning member is a binding belt or a tensioning bolt matched with the connecting groove (3).

5. The winding die according to claim 1, characterized in that: The two support plates (2) are spaced and limited by a protrusion in the middle of the outer frame (1).

6. The winding die according to claim 1, characterized in that: The corners of the outer frame (1) and the support plate (2) are in a smooth arc shape, and a wear-resistant coating is provided on the surface.

7. A method for winding a three-dimensionally wound core using the winding mold according to any one of claims 1 to 6, characterized in that: The following steps are involved: According to the cutting design data, the inner ring core strip and the outer ring core strip are cut into sections for future use; S1: Install a winding mold on the first winding platform, wind the inner ring core strip, remove the single frame inner ring core (5) after winding, remove the support plate (2), repeat twice, and complete three single frame inner ring cores (5) for standby use; S2: assembling three single-frame inner ring cores (5) into a combined inner ring core (6), and performing annealing treatment; S3: Split the qualified combined inner ring core (6) into single frame inner ring cores (5), install the support plate (2) and send them to the second winding platform, wind the outer ring core strip, remove the single frame mixed core (7) after winding, remove the support plate (2), repeat twice, and complete three single frame mixed cores (7) for standby use; S4: Assemble the three single-frame hybrid cores (7) into a combined hybrid core (8), perform secondary annealing, apply glue to finalize the shape, and inspect whether the core is qualified.

8. The winding method according to claim 7, characterized in that: The inner ring core strip is made of silicon steel strip, and the outer ring core strip is made of amorphous alloy strip.

9. The winding method according to claim 8, characterized in that: The annealing temperature in step S2 is 720-800° C., and the annealing time is 3-4 hours. The secondary annealing temperature in step S4 is 320-400° C., and the annealing time is 3-4 hours.

10. The winding method according to claim 9, characterized in that: The step S4 adopts a glass glue curing and shaping process.

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