Vacuum induction heating power supply high-efficiency multi-laminated iron core intermediate frequency transformer

Abstract

The invention relates to the technical field of transformers, in particular to a high-efficiency multi-stacked iron core medium-frequency transformer for a vacuum induction heating power supply, which is characterized in that all-inclined iron sheets adopt a 45-degree chamfer form, the all-inclined iron sheets are mutually stacked to form an iron core, a water cooling group penetrates through the iron core, and when cooling water flows in from one end of the water cooling group and flows out from the other end of the water cooling group, the cooling water exchanges heat with the iron core; the conductor transposition group comprises a first conductor and a second conductor, and the first conductor and the second conductor are subjected to transposition design in the middle; according to the 45-degree full inclined iron core, local loss at the transition position of the iron core is reduced, the overall loss of the iron core is reduced by about 50%, magnetic density of the iron core in the transition area is reduced, local temperature rise of the iron core is reduced, safety and stability of equipment operation are improved, the effective sectional area of the iron core is increased by more than 35% through the design of the multi-stage lamination structure, no-load loss is further reduced by about 25%, and the service life of the equipment is prolonged. The water cooling group with water and electricity separated avoids potential safety hazards caused by contact between cooling water and an electrified conductor.

Description

Technical Field

[0001] The invention relates to the technical field of transformers, in particular to a high-efficiency multi-stacked iron core medium-frequency transformer for a vacuum induction heating power supply. Background Art

[0002] The medium frequency transformer is a key component in the vacuum medium frequency induction heating power supply. It is widely used in metallurgy, national defense, mechanical processing and other departments, as well as casting, forging, shipbuilding, aircraft, automobile manufacturing and other occasions. However, with the increasing requirements for energy efficiency and equipment stability in the industrial field, traditional wound core transformers have gradually exposed many technical bottlenecks, such as limited wire cross-sectional area, large eddy current loss, poor cooling effect and other problems, which make it difficult to meet the needs of efficient and low-loss energy transmission. In addition, the heat dissipation structure of traditional transformers is complex, which increases the volume and manufacturing cost of the system and limits its applicability in certain applications. At present, technical improvements such as water-cooled coils and laminated cores have been developed to improve the performance of medium frequency transformers. The use of water-cooled structure can effectively solve the heat dissipation problem of coils and cores and extend the service life of equipment.

[0003] However, the existing technology still has several limitations, such as the low integration of water-cooled coils and core cooling structures, low mechanical manufacturing efficiency, and inability to fully reduce core losses. On the other hand, due to the limited space for winding wires, the traditional wound core transformer cannot increase the cross-sectional area of ​​the wires, resulting in large wire losses and a low core filling factor, resulting in poor overall efficiency. Summary of the invention

[0004] The main purpose of the present invention is to provide a high-efficiency multi-stacked iron core medium frequency transformer for a vacuum induction heating power supply, so as to solve the problems in the related art that the core loss cannot be fully reduced, the conductor loss is large, and the core filling factor is low.

[0005] In order to achieve the above object, according to one aspect of the present invention, a vacuum induction heating power supply high-efficiency multi-stacked iron core medium-frequency transformer is provided, comprising a transformer, on which a primary winding and a secondary winding are fixedly provided, and further comprising: full-trim iron sheets, the full-trim iron sheets are in the form of 45° chamfers, and the full-trim iron sheets are stacked on each other to form an iron core; A water cooling group, wherein the water cooling group runs through the iron core, and when cooling water flows in from one end of the water cooling group and flows out from the other end, heat exchange occurs with the iron core; A conductor transposition group, the conductor transposition group comprises a first conductor and a second conductor, the first conductor and the second conductor are transposed in the middle.

[0006] Furthermore, the primary winding is fixedly provided with a plurality of lead terminals, and the lead terminals are connected to an external power source to transfer the electric energy of the external power source to the primary winding.

[0007] Furthermore, the secondary winding receives energy from the primary winding through the magnetic field of the transformer.

[0008] Furthermore, multiple layers of coils are wound around the outside of the iron core to form a transformer.

[0009] Furthermore, the transformer adopts a resin casting process to integrally cast the coil and the iron core.

[0010] Furthermore, the cross-sectional area of ​​the core transition region increases from 1 times to 1.414 times when at right angles. According to the magnetic density calculation formula ; Among them, B is the magnetic flux density, Φ is the magnetic flux, and A is the cross-sectional area. Due to the increase in the cross-sectional area of ​​the transition region, the magnetic flux density is reduced to the original 0.707, that is, the magnetic flux density is reduced from Reduced to 0.707 , the loss is proportional to the square of the flux density, so the core loss is reduced to: ; Losses were reduced by 50%.

[0011] Furthermore, the water cooling group includes a water cooling tube and an insulating tube, and the insulating tube runs through the iron core and the coil.

[0012] Furthermore, the water cooling pipe is radially arranged inside the insulating pipe, and the insulating pipe isolates the water cooling pipe from the iron core and the coil.

[0013] Furthermore, the water cooling pipe is provided with a water inlet at one end and a water outlet at the other end. Cooling water flows out of the water cooling pipe from the water inlet and then flows out through the water outlet. The water cooling pipe is located in the insulating tube and radially penetrates the iron core and the coil.

[0014] Furthermore, the conductor transposition group adopts a design of transposing the first conductor and the second conductor, and the cross-sectional area of ​​the double conductors is half of the original, so that the potentials of the first conductor and the second conductor cancel each other out, and the circulating current loss and eddy current loss are proportional to the cross-sectional area of ​​the conductor, and the potential difference will lead to the current concentration effect inside the conductor. In the traditional single copper tube conductor, the eddy current loss It is proportional to the conductor thickness d, that is: ; The cross-sectional area of ​​the double conductor is 50% of the original, that is, the conductor thickness is reduced from d to , the eddy current loss of each conductor becomes: ; Therefore, after being divided into two conductors, the eddy current loss of each conductor is only 1 / 4 of the original. In the double-conductor structure, although the eddy current loss of each conductor is reduced by 75% (that is, only 1 / 4 of the original), because there are two conductors, the total eddy current loss is the sum of the losses of the two conductors: ; In the double-conductor structure, the eddy current loss is 1 / 2 of that of a single conductor, that is, the eddy current loss is reduced by 50%.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. The vacuum induction heating power supply of the present invention has a high efficiency multi-stacked iron core medium frequency transformer. The magnetic flux density is optimized and the loss is reduced. The 45° full-trim iron core increases the cross-sectional area of ​​the transition area, reduces the magnetic flux density by 30%, reduces the local loss at the transition of the iron core, and reduces the overall loss of the iron core by about 50%; 2. The local temperature rise of the high-efficiency multi-stacked iron core medium-frequency transformer of the vacuum induction heating power supply of the present invention is reduced: the iron core reduces the magnetic density in the transition area and reduces the local magnetic loss, thereby effectively reducing the local temperature rise of the iron core. Compared with the traditional design, the local temperature rise is reduced by about 5°C, thereby improving the safety and stability of the equipment operation; 3. The space utilization rate of the high-efficiency multi-stacked iron core medium-frequency transformer of the vacuum induction heating power supply of the present invention is improved: through the multi-stage lamination structure design, the present invention achieves a space utilization rate of more than 95% under the same volume, increases the effective iron core cross-sectional area by more than 35%, and thus reduces the no-load loss by about 25%; 4. The heat dissipation system of the vacuum induction heating power supply high-efficiency multi-stacked iron core medium-frequency transformer of the present invention is optimized: the water-electricity separated water cooling group avoids the safety hazard caused by the contact between cooling water and live conductors in traditional transformers, and the cooling effect is more efficient, and can dissipate heat for the coil and the iron core at the same time, further optimizing the thermal management of the equipment; 5. The eddy current loss of the high-efficiency multi-stacked iron core medium-frequency transformer of the vacuum induction heating power supply of the present invention is reduced: by transposing the double conductors, the induced potential in the conductors is effectively offset, and the circulating current and eddy current loss are reduced. Compared with the traditional single copper tube conductor, the double conductor structure reduces the eddy current loss by 50%; 6. Mechanical strength and simplification of the vacuum induction heating power supply high-efficiency multi-stacked iron core medium frequency transformer of the present invention: The coil and the iron core are integrated and fixed through the resin casting process, which greatly improves the mechanical strength of the equipment, ensures that the equipment remains stable when working under high load, shortens the production cycle, and improves the durability of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1It is an overall schematic diagram of the high-efficiency multi-stacked iron core medium-frequency transformer of the vacuum induction heating power supply of the present invention.

[0017] Figure 2 This is a top view of the full iron sheet of the high-efficiency multi-stacked iron core medium-frequency transformer of the vacuum induction heating power supply of the present invention.

[0018] Figure 3 It is a top view of the superimposed state of the full-iron core of the high-efficiency multi-stacked iron core medium-frequency transformer of the vacuum induction heating power supply of the present invention.

[0019] Figure 4 The present invention is a schematic diagram of the water cooling structure of the high-efficiency multi-stacked iron core medium-frequency transformer of the vacuum induction heating power supply.

[0020] Figure 5 The schematic diagram of the double-conductor structure of the high-efficiency multi-stacked iron core medium-frequency transformer of the vacuum induction heating power supply of the present invention.

[0021] Illustration Description: 1. Primary winding; 2. Secondary winding; 3. Transformer; 4. All-iron sheet; 5. Water cooling tube; 6. First conductor; 7. Second conductor; 8. Insulation tube. DETAILED DESCRIPTION

[0022] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation mode, structure, characteristics and effects of the present invention are described in detail below in combination with the accompanying drawings and preferred embodiments.

[0023] See also Figures 1 to 5 , this embodiment provides a high-efficiency multi-stacked iron core medium-frequency transformer for a vacuum induction heating power supply, including a transformer 3, on which a primary winding 1 and a secondary winding 2 are fixedly provided, and also includes: a full iron sheet 4, the full iron sheet 4 is in the form of a 45° chamfer, and the full iron sheets 4 are superimposed on each other to form an iron core. This design reduces the magnetic density of the connected iron core in the transition area by 30% compared to the magnetic density of the core column, resulting in a reduction of 5°C in the local temperature rise of the core, thereby reducing local heat accumulation. Through the theory of heat conduction, reducing losses directly reduces local temperature rise. This improvement effectively avoids the degradation of equipment performance due to local overheating, and improves the reliability and service life of the equipment; Water cooling group, the water cooling group runs through the iron core. When cooling water flows in from one end of the water cooling group and flows out from the other end, heat exchange occurs with the iron core; The conductor transposition group includes a first conductor 6 and a second conductor 7. The first conductor 6 and the second conductor 7 are transposed in the middle.

[0024] The primary winding 1 is fixedly provided with a plurality of lead terminals, which are connected to an external power source to transfer the electric energy of the external power source to the primary winding 1 .

[0025] The secondary winding 2 receives energy from the primary winding 1 through the magnetic field of the transformer 3 .

[0026] Multiple layers of coils are wound around the outside of the core to form a transformer 3.

[0027] Transformer 3 adopts resin casting process to integrally cast the coil and the core, which simplifies the assembly process of the coil and the core. After the coil and the core are assembled, they are arranged according to the outlet position, and the core and the coil are integrally cast with resin, and the terminal block and the water nozzle extend out of the casting body. This process not only improves the cooling efficiency, but also enhances the mechanical strength and structural compactness.

[0028] The cross-sectional area of ​​the transition region of the iron core made of the full-trim iron sheet 4 with a 45° chamfer increases from 1 times to 1.414 times when it is at a right angle. According to the magnetic density calculation formula: ; B is the magnetic flux density, Φ is the magnetic flux, and A is the cross-sectional area. Due to the increase in the cross-sectional area of ​​the transition region, the magnetic flux density is reduced to the original 0.707, that is, the magnetic flux density is reduced from Reduced to 0.707 , the loss is proportional to the square of the flux density, so the core loss is reduced to: ; The loss is reduced by 50%. There is 25% space waste in the traditional wound core structure, and the utilization rate of the outer circular coil is low due to the different winding lengths of the inner and outer coils. The present invention uses a multi-stage lamination structure to make the inner and outer lengths consistent, and the space utilization rate is increased to 95%, thereby increasing the effective core cross-section by more than 35%. This directly affects the reduction of no-load loss. Based on the traditional no-load loss, the increase in effective area can reduce the no-load loss by about 25%. Due to the reduction of magnetic density in the transition area, the local magnetic loss is directly reduced.

[0029] The water cooling group includes a water cooling tube 5 and an insulating tube 8. The insulating tube 8 runs through the iron core and the coil.

[0030] The water cooling tube 5 is radially arranged inside the insulating tube 8, and the insulating tube 8 isolates the water cooling tube 5 from the iron core and the coil.

[0031] The water cooling pipe 5 is provided with a water inlet at one end and a water outlet at the other end. The cooling water flows out of the water cooling pipe 5 from the water inlet and then flows out through the water outlet. The water cooling pipe 5 is located in the insulating pipe 8 and radially penetrates the iron core and the coil. The function of the insulating pipe 8 is to isolate the water cooling pipe 5 from the iron core and the coil, thereby realizing the design of water-electricity separation and ensuring that the cooling water will not cause electrical safety hazards when in contact with the iron core and the coil. The water cooling pipe 5 is radially arranged between the iron core and the coil through the insulating pipe 8 to ensure that the cooling water can effectively exchange heat with the iron core, while avoiding direct contact between the cooling water and the live parts, thereby improving the safety and heat dissipation performance of the equipment.

[0032] The water cooling pipe 5 is set in the insulating pipe 8 and arranged inside the iron core and the coil. The water cooling pipe 5 and the coil are isolated by the insulating pipe 8 to ensure that the cooling water is not charged, and the cooling water is completely separated from the electrical part of the coil. The cooling water takes away the heat generated by the operation of the coil through the water cooling pipe 5. Due to the water-electricity separation design, the cooling water is not charged, which ensures the safety and reliability of the system and improves the heat dissipation efficiency. The cold water group can effectively dissipate heat for the coil and the iron core at the same time, avoiding the problem of local overheating caused by heat concentration. Since the heat dissipation structure of the coil and the iron core is integrated, the system does not need a separate cooling device, which simplifies the structural design. The water cooling structure not only improves the cooling performance of the equipment, but also reduces the temperature rise of the overall equipment, and the local temperature rise is reduced by about 5°C.

[0033] The conductor transposition group adopts a design of transposing the first conductor 6 and the second conductor 7, and the cross-sectional area of ​​the double conductors is half of the original, so that the potentials of the first conductor 6 and the second conductor 7 cancel each other out, reducing the circulating current and thus reducing the eddy current loss. The circulating current loss and eddy current loss are proportional to the cross-sectional area of ​​the conductor, and the potential difference will lead to the current concentration effect inside the conductor. In the traditional single copper tube conductor, the eddy current loss It is proportional to the conductor thickness d, that is: ; Since the present invention uses double conductors and the cross-sectional area is 50% of the original, that is, the conductor thickness is reduced from d to , the eddy current loss of each conductor becomes: ; Therefore, after being divided into two conductors, the eddy current loss of each conductor is only 1 / 4 of the original. In the double-conductor structure, although the eddy current loss of each conductor is reduced by 75%, that is, only 1 / 4 of the original, because there are two conductors, the total eddy current loss is the sum of the losses of the two conductors: ; In the double-conductor structure, the eddy current loss is 1 / 2 of that of a single conductor, that is, the eddy current loss is reduced by 50%. Through the transposition structure, the potential in the conductors is offset and the circulating current is almost zero, which further reduces the circulating current loss on the basis of reducing it to 35%.

[0034] The two conductors are connected in parallel and transposed in the middle. The cross-sectional area of ​​each conductor is half of that of the original single conductor, which means that the thickness of each conductor is reduced from d to d / 2. With this arrangement, the induced potentials between the conductors can cancel each other out, thereby reducing the circulating current and eddy current loss in the conductors. The double conductors are arranged along the core and are associated with the magnetic field effect of the core. Since the magnetic flux distribution of the core is optimized in the transition area of ​​the core (the magnetic flux density is reduced by the 45° joint design), the potential difference of the double conductors is further reduced, forming a more stable current conduction path. The eddy current loss is proportional to the conductor thickness. This arrangement reduces the current concentration effect.

[0035] Multiple 45° angled full-tungsten iron sheets are stacked in 4 layers to form an iron core. The cross-sectional area of ​​the transition region of the iron core is increased from 1 times of the original right-angle iron core to 1.414 times, reducing the core loss. At the same time, the inner and outer lengths of the iron core are consistent, and the space utilization rate is increased to 95%, thereby increasing the effective core cross-section by more than 35% and reducing the no-load loss. The primary winding 1 is connected to an external power supply through multiple lead-out terminals, receives the external electrical energy, and transmits the energy to the secondary winding 2 through the magnetic field of the transformer 3. The secondary winding 2 transmits the energy transmitted by the primary winding 1 It is output to the external load in the form of appropriate voltage or current, and cooling water is added to the water inlet of the water-cooling pipe 5. The cooling water flows forward along the water-cooling pipe 5, contacts the iron core and the coil respectively, exchanges heat with the iron core and the coil, and takes away the heat from the contact surface. The temperature of the cooling water after the heat exchange becomes higher, and then flows out from the water outlet of the water-cooling pipe 5. A steady stream of cooling water enters from the water inlet of the water-cooling pipe 5 and then flows out from the water outlet, continuously dissipating heat for the iron core and the coil, keeping the iron core and the coil in a low temperature state during the power transmission process, thereby extending the service life of the iron core and the coil.

[0036] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A high-efficiency multi-stacked iron core medium-frequency transformer for vacuum induction heating power supply, comprising a transformer (3), characterized in that: The transformer (3) is fixedly provided with a primary winding (1) and a secondary winding (2), and further comprises: Fully tantalum iron sheets (4), the full tantalum iron sheets (4) being chamfered at 45°, and the full tantalum iron sheets (4) being superimposed on each other to form an iron core; A water cooling group, wherein the water cooling group runs through the iron core, and when cooling water flows in from one end of the water cooling group and flows out from the other end, heat exchange occurs with the iron core; A conductor transposition group, the conductor transposition group comprising a first conductor (6) and a second conductor (7), the first conductor (6) and the second conductor (7) being transposed in the middle.

2. The vacuum induction heating power supply high-efficiency multi-stacked iron core medium-frequency transformer according to claim 1 is characterized in that: The primary winding (1) is fixedly provided with a plurality of lead terminals, the lead terminals being connected to an external power source to transfer the electric energy of the external power source to the primary winding (1).

3. The high-efficiency multi-stacked iron core medium-frequency transformer for vacuum induction heating power supply according to claim 2 is characterized in that: The secondary winding (2) receives energy from the primary winding (1) through the magnetic field of the transformer (3).

4. The vacuum induction heating power supply high-efficiency multi-stacked iron core medium-frequency transformer according to claim 1 is characterized in that: Multiple layers of coils are wound around the outside of the iron core to form a transformer (3).

5. The vacuum induction heating power supply high-efficiency multi-stacked iron core medium-frequency transformer according to claim 4 is characterized in that: The transformer (3) adopts a resin casting process to integrally cast the coil and the iron core.

6. The high-efficiency multi-stacked iron core medium-frequency transformer for vacuum induction heating power supply according to claim 1, characterized in that: The cross-sectional area of ​​the core transition region increases from 1 times to 1.414 times when at right angles. According to the magnetic density calculation formula: ； Among them, B is the magnetic flux density, Φ is the magnetic flux, and A is the cross-sectional area. Due to the increase in the cross-sectional area of ​​the transition region, the magnetic flux density is reduced to the original 0.707, and the magnetic flux density is Reduced to 0.707 , the loss is proportional to the square of the flux density, so the core loss is reduced to: ； That means the loss is reduced by 50%.

7. The high-efficiency multi-stacked iron core medium-frequency transformer for vacuum induction heating power supply according to claim 1 is characterized in that: The water cooling group comprises a water cooling tube (5) and an insulating tube (8), and the insulating tube (8) passes through the iron core and the coil.

8. The high-efficiency multi-stacked iron core medium-frequency transformer for vacuum induction heating power supply according to claim 7 is characterized in that: The water cooling tube (5) is radially arranged inside the insulating tube (8), and the insulating tube (8) isolates the water cooling tube (5) from the iron core and the coil.

9. The high-efficiency multi-stacked iron core medium-frequency transformer for vacuum induction heating power supply according to claim 7, characterized in that: The water cooling pipe (5) is provided with a water inlet at one end and a water outlet at the other end. Cooling water flows out of the water cooling pipe (5) from the water inlet and then flows out through the water outlet. The water cooling pipe (5) is located inside the insulating pipe (8) and penetrates the iron core and the coil in the radial direction.

10. The high-efficiency multi-stacked iron core medium-frequency transformer for vacuum induction heating power supply according to claim 1, characterized in that: The conductor transposition group adopts a design of transposing two conductors, namely, a first conductor (6) and a second conductor (7), and the cross-sectional area of ​​the two conductors is half of the original, so that the potentials of the first conductor (6) and the second conductor (7) cancel each other out, and the circulating current loss and eddy current loss are proportional to the cross-sectional area of ​​the conductors. The potential difference will lead to a current concentration effect inside the conductor. In a traditional single copper tube conductor, the eddy current loss It is proportional to the conductor thickness d, that is: ； The cross-sectional area of ​​the double conductor is 50% of the original, that is, the conductor thickness is reduced from d to , the eddy current loss of each conductor becomes: ； Therefore, after being divided into two conductors, the eddy current loss of each conductor is only 1 / 4 of the original. In the double-conductor structure, the eddy current loss of each conductor is reduced by 75% to 1 / 4 of the original. The total eddy current loss of the two conductors is the sum of the losses of the two conductors: ； In the double-conductor structure, the eddy current loss is 1 / 2 of that of a single conductor, that is, the eddy current loss is reduced by 50%.

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