An oil-cooled high-voltage transformer and an X-ray high-voltage generator

Abstract

The present invention discloses an oil-cooled high-voltage transformer, comprising a transformer line group, a first magnetic core and a second magnetic core, the transformer line group comprises a high-voltage wire package, a low-voltage wire package and a high-voltage insulating cylinder, the high-voltage insulating cylinder is a hollow cylindrical structure with two ends open, the low-voltage wire package is arranged around the inner wall of the high-voltage insulating cylinder, the low-voltage wire package leads to a plurality of low-voltage access terminals, the high-voltage wire package is arranged around the outside of the high-voltage insulating cylinder, the high-voltage wire package leads to a plurality of high-voltage output terminals, the first magnetic core comprises a first outer cylinder and a first central axis, the second magnetic core comprises a second outer cylinder and a second central axis, the first outer cylinder and the second outer cylinder are both semi-enclosed cylindrical structures, the first central axis is arranged inside the first outer cylinder, and the second central axis is arranged inside the second outer cylinder. This technical solution is used to solve the problem that the existing transformer is difficult to meet the requirements of high-frequency products.

Description

Technical Field

[0001] The invention belongs to the technical field of transformer equipment, and in particular relates to an oil-cooled high-voltage transformer and an X-ray high-voltage generator. Background Art

[0002] A transformer is a device that uses the principle of electromagnetic induction to change AC voltage. Its main components are primary coil, secondary coil and iron core. Its main functions include voltage conversion, current conversion, impedance conversion, isolation, voltage stabilization, etc. In some special fields, such as medical X-ray machines, there are high requirements for the operating frequency of transformers. The applicable frequency of existing products is lower than 20KHz, which cannot meet the needs of high-frequency products. It is easy to have problems such as electrical breakdown or overheating and burning during use. In addition, the existing transformers have poor coupling and are prone to leakage inductance loss. Summary of the invention

[0003] In view of the above-mentioned technical problems, the present invention provides an oil-cooled high-voltage transformer and a medical X-ray machine to solve the problem that existing transformers are difficult to meet the requirements of high-frequency products. The oil-cooled high-voltage transformer has good coupling and rapid cooling performance.

[0004] The present invention provides an oil-cooled high-voltage transformer, comprising a transformer line group, a first magnetic core and a second magnetic core, the transformer line group comprising a high-voltage wire package, a low-voltage wire package and a high-voltage insulating cylinder, the high-voltage insulating cylinder being a hollow cylindrical structure with two ends open, the low-voltage wire package being arranged around the inner wall of the high-voltage insulating cylinder, the low-voltage wire package leading out a plurality of low-voltage access terminals, the high-voltage wire package being arranged around the outside of the high-voltage insulating cylinder, the high-voltage wire package leading out a plurality of high-voltage output terminals, the first magnetic core comprising a first outer cylinder and a first central axis, the second magnetic core comprising a second outer cylinder and a second central axis, the first outer cylinder and the second outer cylinder being both semi-enclosed cylindrical structures, the first The central axis is arranged inside the first outer cylinder, and the second central axis is arranged inside the second outer cylinder. The first outer cylinder and the second outer cylinder are arranged opposite to each other and connected to each other to form a cooling cavity for insulating oil to pass through between the first outer cylinder and the second outer cylinder. The transformer line group is located in the cooling cavity. The first central axis and the second central axis are inserted into the high-voltage insulating cylinder from both ends of the high-voltage insulating cylinder, and the low-voltage wire package surrounds the outer circumference of the first central axis and the second central axis. The first magnetic core and the second magnetic core are both MnZn ferrite, and the surfaces of the first magnetic core and the second magnetic core are covered with an insulating epoxy layer and a polyimide coating.

[0005] Furthermore, the high-voltage wire package and the low-voltage wire package are both designed as circular coils.

[0006] Furthermore, the transformer line group also includes a low-voltage insulating cylinder, the high-voltage insulating cylinder is sleeved on the outside of the low-voltage insulating cylinder, the low-voltage wire package is surrounded by the outer wall of the low-voltage insulating cylinder, the first center axis and the second center axis penetrate into the low-voltage insulating cylinder, and the outer wall of the high-voltage insulating cylinder is provided with a plurality of annular grooves for accommodating the high-voltage wire package.

[0007] Furthermore, the transformer line group also includes a plurality of high-voltage isolation rings, which are made of insulating material. The plurality of high-voltage isolation rings are arranged at intervals along the axial direction of the high-voltage insulating cylinder on the outer periphery of the high-voltage insulating cylinder, and the high-voltage wire package is divided into a plurality of parts by the plurality of high-voltage isolation rings.

[0008] Furthermore, a liquid inlet and a liquid outlet are respectively provided on two outer walls away from each other of the cooling chamber, and the liquid inlet and the liquid outlet are formed on the first outer tube and the second outer tube.

[0009] Furthermore, the liquid inlet and the liquid outlet are both bar-shaped through holes, the low-voltage access terminal is introduced through the liquid inlet, and the high-voltage output terminal is led out through the liquid inlet or the liquid outlet.

[0010] Furthermore, a polytetrafluoroethylene joint is provided at the end of the high voltage output terminal.

[0011] Furthermore, it also includes a first insulating gasket, a second insulating gasket, a first bracket and a second bracket, the first bracket is arranged on the end of the first magnetic core facing away from the second magnetic core, the first insulating gasket is located between the first bracket and the first magnetic core, the second bracket is arranged on the end of the second magnetic core facing away from the first magnetic core, and the second insulating gasket is located between the second bracket and the second magnetic core.

[0012] Furthermore, it also includes a screw, an insulating tube and a nut. The first center axis and the second center axis are both hollow structures, and the first center axis and the second center axis are connected. The screw passes through the first bracket, the first insulating gasket, the first center axis, the second center axis, the second insulating gasket and the second bracket in sequence and is connected to the nut.

[0013] The present invention also provides an X-ray high voltage generator, comprising the oil-cooled high voltage transformer as described above.

[0014] The oil-cooled high-voltage transformer adopts the drawer-type combination to increase the magnetic coupling between the windings and reduce unnecessary leakage inductance loss of the transformer. The first magnetic core is set as the first outer cylinder and the first central axis, and the second magnetic core is set as the second outer cylinder and the second central axis. The two are combined to form a cooling chamber, and insulating oil can be introduced to cool the oil-cooled high-voltage transformer to avoid overheating. The first outer cylinder and the second outer cylinder form an inner and outer isolated space. Due to the temperature difference between the high temperature inside the transformer and the external insulating oil, the circulation of the insulating oil in the transformer is accelerated, so that the transformer is quickly cooled. Specifically, after the oil-cooled high-voltage transformer is powered on, the internal transformer line group will start to heat up, resulting in an increase in the pressure difference between the inside and the surface of the oil-cooled high-voltage transformer. Therefore, the increase in internal temperature will accelerate the movement speed of the internal insulating oil, so that the external low-temperature insulating oil and the internal high-temperature insulating oil form convection, so that the temperature of the oil-cooled high-voltage transformer drops and finally reaches an equilibrium value. At the same time, the first center axis and the second center axis improve the coupling effect between the high-voltage wire package and the low-voltage wire package, while the first outer cylinder and the second outer cylinder effectively isolate the risk of high-voltage wave leakage. The first magnetic core and the second magnetic core are made of MnZn ferrite, which can adapt to high frequency and reduce loss. The use frequency range is increased to 1MHz level, meeting the high-frequency requirements of the product; by arranging an insulating epoxy layer and a polyimide coating on the surface of the first magnetic core and the second magnetic core, the high-voltage strength can be increased, and the insulation withstand voltage can reach 350KV. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 It is a structural schematic diagram of an oil-cooled high-voltage transformer;

[0017] Figure 2 It is an exploded diagram of an oil-cooled high-voltage transformer;

[0018] Figure 3 It is the exploded diagram of the transformer line group;

[0019] Figure 4 It is a schematic diagram of the insulating oil flow of an oil-cooled high-voltage transformer;

[0020] Figure 5 The working principle diagram of an oil-cooled high-voltage transformer. DETAILED DESCRIPTION

[0021] The invention discloses an oil-cooled high-voltage transformer and a medical X-ray machine. The oil-cooled high-voltage transformer has good coupling performance and rapid cooling performance.

[0022] The following will be combined with the accompanying drawings in the present invention to clearly and completely describe the technical solutions in the present invention. Obviously, what is described is only a part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] See also Figure 1 to Figure 5 As shown, the present invention discloses an oil-cooled high-voltage transformer, including a transformer line group 4, a first magnetic core 1 and a second magnetic core 2, the transformer line group 4 includes a high-voltage wire package 20, a low-voltage wire package 18 and a high-voltage insulating cylinder 1321, the high-voltage insulating cylinder 1321 is a hollow cylindrical structure with two ends open, the low-voltage wire package 18 is arranged around the inner wall of the high-voltage insulating cylinder 1321, and the low-voltage wire package 18 leads to a plurality of low-voltage access terminals 5, the high-voltage wire package 20 is arranged around the outside of the high-voltage insulating cylinder 1321, and the high-voltage wire package 20 leads to a plurality of high-voltage output terminals 6, the first magnetic core 1 includes a first outer cylinder 7 and a first central axis 8, the second magnetic core 2 includes a second outer cylinder 12 and a second central axis, the first outer cylinder 7 and the second outer cylinder 12 are both semi-enclosed cylinders The structure comprises a first central axis 8 disposed inside the first outer cylinder 7, and the second central axis disposed inside the second outer cylinder 12. The first outer cylinder 7 and the second outer cylinder 12 are disposed opposite to each other and are interconnected to form a cooling cavity 24 for insulating oil to pass therethrough between the first outer cylinder 7 and the second outer cylinder 12. The transformer line group 4 is located in the cooling cavity 24. The first central axis 8 and the second central axis are inserted into the high-voltage insulating cylinder 1321 from both ends of the high-voltage insulating cylinder 1321, and the low-voltage wire package 18 surrounds the outer circumference of the first central axis 8 and the second central axis. The first magnetic core 1 and the second magnetic core 2 are both MnZn ferrites, and the surfaces of the first magnetic core 1 and the second magnetic core 2 are covered with insulating epoxy layers and polyimide coatings.

[0024] The oil-cooled high-voltage transformer adopts the drawer-type combination to increase the magnetic coupling between the windings and reduce unnecessary leakage inductance loss of the transformer. The first magnetic core 1 is set as the first outer cylinder 7 and the first central axis 8, and the second magnetic core 2 is set as the second outer cylinder 12 and the second central axis. The two are combined to form a cooling chamber 24, which can be passed through insulating oil to cool the oil-cooled high-voltage transformer to avoid overheating. The first outer cylinder and the second outer cylinder form an inner and outer isolated space. Due to the temperature difference between the high temperature inside the transformer and the external insulating oil, the circulation of the insulating oil in the transformer is accelerated to achieve rapid cooling of the transformer. Specifically, after the oil-cooled high-voltage transformer is powered on, the internal transformer line group will start to heat up, resulting in an increase in the pressure difference between the inside and the surface of the oil-cooled high-voltage transformer. Therefore, the increase in internal temperature will accelerate the movement speed of the internal insulating oil, so that the external low-temperature insulating oil and the internal high-temperature insulating oil form convection, so that the temperature of the oil-cooled high-voltage transformer drops and finally reaches an equilibrium value. At the same time, the first central axis 8 and the second central axis improve the coupling effect between the high-voltage wire package 20 and the low-voltage wire package 18, while the first outer cylinder 7 and the second outer cylinder 12 effectively isolate the risk of high-voltage wave leakage. The first magnetic core 1 and the second magnetic core 2 use MnZn ferrite, which can adapt to high frequency and reduce loss. The use frequency range is increased to 1MHz level, meeting the high-frequency requirements of the product; by arranging an insulating epoxy layer and a polyimide coating on the surface of the first magnetic core 1 and the second magnetic core 2, the high-voltage strength can be increased, the insulation withstand voltage can reach 350KV, and the use frequency range is increased to MHz level.

[0025] Specifically, the insulating epoxy layer can be selected from insulating epoxy powder with the brand name HLG03R. The polyimide coating can be selected from polyimide resin with the brand name Kapton.

[0026] The coils of some existing transformers are rectangular windings, which will form tip voltages at the corners, causing tip discharges. To avoid this problem, in the present invention, the high-voltage wire package 20 and the low-voltage wire package 18 are both circular coil designs.

[0027] The high-voltage wire package 20 and the low-voltage wire package 18 adopt a circular design to allow the high-voltage coil wire to bend naturally, thereby avoiding discharge at the tip of the product.

[0028] The transformer line group 4 also includes a low-voltage insulating tube 1319, the high-voltage insulating tube 1321 is sleeved on the outside of the low-voltage insulating tube 1319, the low-voltage wire package 18 is surrounded by the outer wall of the low-voltage insulating tube 1319, the first center axis 8 and the second center axis penetrate into the low-voltage insulating tube 1319, and a plurality of annular grooves 22 for accommodating the high-voltage wire package 20 are opened on the outer wall of the high-voltage insulating tube 1321.

[0029] The transformer line group 4 also includes a plurality of high-voltage isolation rings 23, which are made of insulating material. The plurality of high-voltage isolation rings 23 are arranged at intervals along the axial direction of the high-voltage insulating cylinder 1321 on the outer periphery of the high-voltage insulating cylinder 1321, and the high-voltage wire package 20 is divided into a plurality of parts by the plurality of high-voltage isolation rings 23.

[0030] The high-voltage insulating cylinder 1321 is made of multi-stage isolation to achieve winding voltage sharing. When the winding reaches a certain high voltage, a high-voltage isolation ring 23 is used to increase the high-voltage isolation to achieve higher electrical protection. This structure can reduce the difficulty of selecting raw material insulation, increase the selectivity of insulation materials, and expand the high-voltage design range.

[0031] A liquid inlet 11 and a liquid outlet 25 are respectively formed on two outer walls of the cooling chamber 24 that are away from each other. The liquid inlet 11 and the liquid outlet 25 are formed on the first outer tube 7 and the second outer tube 12 .

[0032] The liquid inlet 11 and the liquid outlet 25 are both bar-shaped through holes. The low-voltage access terminal 5 is introduced through the liquid inlet 11 , and the high-voltage output terminal 6 is led out through the liquid inlet 11 or the liquid outlet 25 .

[0033] The end of the high voltage output terminal 6 is provided with a polytetrafluoroethylene connector to achieve better insulation and faster connection at the output end.

[0034] The oil-cooled high-voltage transformer also includes a first insulating gasket 10, a second insulating gasket 16, a first bracket 9 and a second bracket 17, the first bracket 9 is arranged on the end of the first magnetic core 1 away from the second magnetic core 2, the first insulating gasket 10 is located between the first bracket 9 and the first magnetic core 1, the second bracket 17 is arranged on the end of the second magnetic core 2 away from the first magnetic core 1, and the second insulating gasket 16 is located between the second bracket 17 and the second magnetic core 2.

[0035] The oil-cooled high-voltage transformer also includes a screw 14, an insulating cylinder 13 and a nut 15. The first center axis 8 and the second center axis are both hollow structures, and the first center axis 8 and the second center axis are butt-jointed. The screw 14 sequentially passes through the first bracket 9, the first insulating gasket 10, the first center axis 8, the second center axis, the second insulating gasket 16 and the second bracket 17 and is connected to the nut 15.

[0036] The design of this cooling system can increase the load-bearing capacity of products with the same power. Under the same volume condition, the original 40KW product can be increased to 80KW. The transformer is derated for subsequent development and design, reducing the total product loss.

[0037] The present invention also provides an X-ray high voltage generator, comprising the oil-cooled high voltage transformer as described above.

[0038] The above contents are further detailed descriptions of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.

Claims

1. An oil-cooled high-voltage transformer, characterized in that: The invention comprises a transformer line group, a first magnetic core and a second magnetic core, wherein the transformer line group comprises a high-voltage line package, a low-voltage line package and a high-voltage insulating cylinder, wherein the high-voltage insulating cylinder is a hollow cylindrical structure with two ends open, wherein the low-voltage line package is arranged around the inner wall of the high-voltage insulating cylinder, wherein the low-voltage line package leads to a plurality of low-voltage access terminals, wherein the high-voltage line package is arranged around the outside of the high-voltage insulating cylinder, wherein the high-voltage line package leads to a plurality of high-voltage output terminals, wherein the first magnetic core comprises a first outer cylinder and a first central axis, wherein the second magnetic core comprises a second outer cylinder and a second central axis, wherein the first outer cylinder and the second outer cylinder are both semi-enclosed cylindrical structures, wherein the first central axis is arranged at the inner wall of the high-voltage insulating cylinder, wherein the low-voltage line package leads to a plurality of low-voltage access terminals, wherein the high-voltage line package leads to a plurality of low ... high-voltage line package leads to a plurality of high-voltage output terminals, wherein the first magnetic core comprises a first outer cylinder and a first central axis, wherein the first magnetic core comprises a first outer cylinder and a first central axis, wherein the first outer cylinder and the second outer cylinder are semi-enclosed cylindrical structures, wherein the first central axis is arranged at the inner wall of the high-voltage insulating cylinder, wherein the low-voltage line package leads to a plurality of low-voltage access terminals, wherein the high-voltage line package leads to a plurality of low-voltage access terminals, wherein the high-voltage line package leads to a plurality of low-voltage output terminals, wherein the high-voltage line package leads to a plurality of low-voltage output The second center axis is arranged inside the first outer cylinder, the first outer cylinder and the second outer cylinder are arranged opposite to each other and connected to each other to form a cooling cavity for insulating oil to pass through between the first outer cylinder and the second outer cylinder, the transformer line group is located in the cooling cavity, the first center axis and the second center axis are inserted into the high-voltage insulating cylinder from both ends of the high-voltage insulating cylinder, and the low-voltage wire package surrounds the outer circumference of the first center axis and the second center axis, the first magnetic core and the second magnetic core are both MnZn ferrite, and the surfaces of the first magnetic core and the second magnetic core are covered with an insulating epoxy layer and a polyimide coating.

2. The oil-cooled high-voltage transformer according to claim 1, characterized in that: The high-voltage wire package and the low-voltage wire package are both designed as circular coils.

3. The oil-cooled high-voltage transformer according to claim 1, characterized in that: The transformer line group also includes a low-voltage insulating cylinder, the high-voltage insulating cylinder is sleeved on the outside of the low-voltage insulating cylinder, the low-voltage wire package is surrounded by the outer wall of the low-voltage insulating cylinder, the first center axis and the second center axis penetrate into the low-voltage insulating cylinder, and the outer wall of the high-voltage insulating cylinder is provided with a plurality of annular grooves for accommodating the high-voltage wire package.

4. The oil-cooled high-voltage transformer according to claim 2, characterized in that: The transformer line group also includes a plurality of high-voltage isolation rings, which are made of insulating material and are arranged at intervals along the axial direction of the high-voltage insulating cylinder on the outer periphery of the high-voltage insulating cylinder. The high-voltage wire package is divided into a plurality of parts by the plurality of high-voltage isolation rings.

5. The oil-cooled high-voltage transformer according to claim 1, characterized in that: A liquid inlet and a liquid outlet are respectively provided on two outer walls of the cooling chamber that are away from each other. The liquid inlet and the liquid outlet are formed on the first outer tube and the second outer tube.

6. The oil-cooled high-voltage transformer according to claim 5, characterized in that: The liquid inlet and the liquid outlet are both bar-shaped through holes, the low-voltage access terminal is introduced through the liquid inlet, and the high-voltage output terminal is led out through the liquid inlet or the liquid outlet.

7. The oil-cooled high-voltage transformer according to claim 1, characterized in that: A polytetrafluoroethylene joint is provided at the end of the high voltage output terminal.

8. The oil-cooled high-voltage transformer according to claim 1, characterized in that: It also includes a first insulating gasket, a second insulating gasket, a first bracket and a second bracket, the first bracket is arranged on the end of the first magnetic core facing away from the second magnetic core, the first insulating gasket is located between the first bracket and the first magnetic core, the second bracket is arranged on the end of the second magnetic core facing away from the first magnetic core, and the second insulating gasket is located between the second bracket and the second magnetic core.

9. The oil-cooled high-voltage transformer according to claim 8, characterized in that: It also includes a screw, an insulating tube and a nut. The first center axis and the second center axis are both hollow structures, and the first center axis and the second center axis are butt-jointed. The screw passes through the first bracket, the first insulating gasket, the first center axis, the second center axis, the second insulating gasket and the second bracket in sequence and is connected to the nut.

10. An X-ray high voltage generator, characterized in that: It comprises an oil-cooled high-voltage transformer as described in any one of claims 1 to 9.

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