An offshore wind power transmission dry-type transformer

Abstract

The invention discloses an offshore wind power transmission dry-type transformer, which belongs to the technical field of transformers and aims to solve the problems of weak sea breeze erosion resistance, poor heat dissipation effect and high noise in the existing offshore wind power transmission dry-type transformers. The transformer comprises an iron core, a clamp for fixing the iron core and a coil wound around the outside of the iron core. The outside of the iron core inside the coil is wrapped with heat shrinkable tapes distributed up and down, flame-retardant glass angle steels are installed at the four corners of the iron core outside the heat shrinkable tapes, an NHN flame-retardant insulation layer for completely wrapping the iron core is arranged outside the flame-retardant glass angle steel, and the iron core and the coil are treated with corrosion prevention. Since the iron core and the coil are core components of the transformer and are also areas prone to failure due to sea breeze erosion, the iron core and the coil are wrapped with resin, thereby making them have very high corrosion resistance, thereby ensuring the stability and safety of operation and extending the service life.

Description

Technical Field

[0001] The invention discloses an offshore wind power transmission dry-type transformer, which belongs to the technical field of transformers, and in particular relates to the technical field of offshore wind power transmission dry-type transformers. Background Art

[0002] Offshore wind power is a new direction for clean energy in the future. As the economically exploitable wind resources on land are becoming less and less, the global wind farm construction has shown a trend of developing from land to offshore. Compared with land wind, offshore wind power resources have higher energy efficiency than land wind farms and can reduce the cost of electricity transportation. In addition, since the most abundant offshore wind energy resources are in the southeast coastal areas, adjacent to economically developed areas with large electricity demand, it can be digested nearby and reduce transportation costs, so there is huge development potential. Compared with onshore wind power, offshore wind power transformers need to consider more external factors.

[0003] For example, since the sea breeze contains a large amount of salt mist and moisture, these salt mist and moisture will cause certain erosion to the transformer when flowing through it. Since most transformers lack anti-corrosion structures inside, most of the transformers currently used in offshore wind power are very prone to failure under the erosion of sea breeze. Some transformers are placed indoors to protect the transformer, but the indoor air is not circulated, which is very inconvenient for the heat dissipation of the transformer, causing the transformer to work in a high temperature environment for a long time, reducing the service life of the transformer. In order to solve the above problems, we propose an offshore wind power transmission dry-type transformer. Summary of the invention

[0004] The purpose of the present invention is to provide an offshore wind power transmission dry-type transformer to solve the problems of weak sea breeze erosion resistance, poor heat dissipation effect and high noise in the above-mentioned existing offshore wind power transmission dry-type transformers.

[0005] The technical solution adopted by the present invention is as follows:

[0006] An offshore wind power transmission dry-type transformer comprises an iron core, a clamp for fixing the iron core, and a coil wound around the outside of the iron core, wherein the outside of the iron core inside the coil is wrapped with heat shrinkable tapes distributed up and down, flame-retardant glass angle steels are installed at the four corners of the iron core outside the heat shrinkable tapes, and an NHN flame-retardant insulation layer that completely wraps the iron core is arranged outside the flame-retardant glass angle steel, I-shaped struts are distributed between layers inside the coil, and the inside of the coil between two adjacent I-shaped struts is arranged with a coil air duct that is connected up and down, and the iron core and the coil are subjected to anti-corrosion treatment after being assembled.

[0007] Furthermore, an insulating sleeve is sleeved on the outside of the limiting screw inside the clamp, an insulating end ring is sleeved on the limiting screw between the clamp and the nut, a terminal block for output and input current is installed on the top of the clamp, a protective plate is installed on the top of the clamp outside the terminal block, and a hanging ring is also distributed on the top of the clamp.

[0008] Furthermore, an air duct is arranged between the clamp and the iron core, a gap is arranged between the iron core around the flame-retardant glass angle steel and the NHN flame-retardant insulating layer, and the gap is connected to the air duct.

[0009] Furthermore, a bottom plate is installed at the bottom end of the clamp, a gasket is arranged between the bottom plate and the clamp, a hard plastic block is arranged inside the gasket, a rubber sheet is wrapped outside the hard plastic block, and a silicone plate is wrapped outside the rubber sheet.

[0010] Furthermore, the iron core is made of non-oriented silicon steel sheets, and the non-oriented silicon steel sheets are made using a full-slant process.

[0011] Furthermore, the inside of the coil is copper wire, and the outside of the copper wire is first wrapped with two layers of imide film and then wrapped with two layers of glass fiber. The specific processing steps are: conductor (copper, aluminum) - film wrapping - painting - glass fiber wrapping - painting - baking - dipping - glass fiber wrapping - dipping - drying - product winding - inspection - storage, the specific process is as follows:

[0012] Step 1: Check whether the conductor used meets the standard requirements. Only qualified ones can be put into production;

[0013] Step 2: Pull the qualified conductor to the film wrapping head, stop the machine, install the film and stick it;

[0014] Step 3: Start the machine and pull the wire end to the first winding head of the glass fiber, stop the machine, install the glass fiber group, and add the corresponding insulating paint to the first and second paint cylinders;

[0015] Step 4: Start the machine, bake the wire end once, and then pull it to the second winding head of the glass fiber. Stop the machine, install the glass fiber group, and add the corresponding insulating paint to the third and fourth paint cylinders;

[0016] Step 5: Start the machine, dry the thread ends several times, and pull them to the take-up point. Then stop the machine for the first product inspection. Only qualified ones can be loaded for production;

[0017] Step 6: Place qualified products on product circulation cards and wait for inspection before storage.

[0018] Furthermore, the process of anti-corrosion treatment of the iron core and the coil is as follows:

[0019] Step 1: Pre-baking the core and coil; the pre-baking temperature is 120-140°C, and the time is 2-4 hours;

[0020] Step 2: Cooling of the core and coil: When the workpiece is dipped in resin, the temperature is cooled to ﹤50℃;

[0021] Step 3: Vacuum pressure impregnation: It is best to pre-stir 116HU for 15~20 minutes before impregnating the resin, place the iron core and coil in the impregnation tank, lock the tank cover, evacuate the tank until the residual pressure (vacuum degree) in the impregnation tank is <400Pa, and maintain it for 15~30 minutes, transfer the resin to the liquid level 50~100mm higher than the part of the workpiece to be impregnated, maintain a vacuum of <1000Pa for 30 minutes, release the vacuum, pressurize to 0.4~0.6MPa, and maintain the pressure for 0.5~1h, release the pressure to 0.4Mpa, and return the resin.

[0022] Step 4: drip resin: drip resin for ≥60min after returning the resin or until there is no resin on the surface of the iron core and coil;

[0023] Step 5: Baking the core and coil: Bake at 140~160℃ for 3~8h. When the hot insulation resistance is stable and the paint film is smooth and non-sticky, it is ready. For workpieces with hot insulation resistance requirements, the hot insulation resistance should be guaranteed to be stable for 3 hours and greater than the specified value.

[0024] Furthermore, the insulating sleeve is a silicone glass fiber sleeve, which is made by weaving alkali-free glass fiber yarn into a tube and then coating it with silicone and treating it at high temperature.

[0025] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0026] 1. The iron core and coil are treated with anti-corrosion. As the core components of the transformer, they are also the areas prone to failure due to sea breeze erosion. The iron core and coil are wrapped with resin to give them very high corrosion resistance, thereby ensuring the stability and safety of operation and extending the service life.

[0027] 2. I-shaped struts are distributed inside the coil. The I-shaped struts form a coil air duct that is connected up and down between the inner and outer rings of the coil, so that the heat dissipation airflow can pass through the inside of the coil, thereby achieving fast and efficient heat dissipation of the coil, avoiding the transformer from working in a high temperature environment for a long time, and extending the service life of the transformer. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention;

[0029] Figure 2 It is a schematic diagram of the bottom end of the three-dimensional structure of the present invention;

[0030] 1- iron core; 2- clamp; 3- limit screw; 4- nut; 5- gasket; 6- terminal block; 7- guard plate; 8- air duct; 9- heat shrink tape; 10- flame retardant glass angle steel; 11- coil; 12- I-beam support bar; 13- bottom plate; 14- pad; 15- lifting ring. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. Example

[0032] like Figure 1 to Figure 2 As shown in, an offshore wind power transmission dry-type transformer includes an iron core 1, a clamp 2 for fixing the iron core 1, and a coil 11 wound around the outside of the iron core 1. The outside of the iron core 1 inside the coil 11 is wrapped with heat shrink tapes 9 distributed up and down. When assembling the iron core 1, it is first clamped by auxiliary tooling, and then tightened by at least three heat shrink tapes 9, thereby ensuring the installation firmness of the iron core 1. At the same time, since most of the iron core 1 is not covered by the heat shrink tape 9, the heat dissipation of the iron core 1 is facilitated. Flame-retardant glass angle steels 10 are installed at the four corners of the iron core 1 outside the heat shrink tape 9, and an NHN flame-retardant insulation layer that completely wraps the iron core 1 is arranged on the outside of the flame-retardant glass angle steel 10. The flame-retardant glass angle steel 10 serves as a support layer for the NHN flame-retardant insulation layer, and at the same time, a certain gap is provided between the NHN flame-retardant insulation layer and the iron core 1, thereby facilitating heat dissipation airflow. The passage of the core 1 and the coil 11 is ensured, and the insulation effect between the core 1 and the coil 11 is also ensured. The setting of the NHN flame-retardant insulating layer also makes the core 1 and the coil 11 have a good flame-retardant effect. I-shaped struts 12 are distributed between the layers inside the coil 11, and the coil 11 between two adjacent I-shaped struts 12 is provided with a coil air duct connected up and down, so that the air flow can pass through the coil air duct, thereby facilitating the heat dissipation of the coil 11. After the core 1 and the coil 11 are assembled, they are subjected to anti-corrosion treatment, so that the connection between the core 1 and the coil 11 is not only very stable, but also has a good effect of resisting sea breeze erosion. The assembly process of the core 1 and the coil 11 is as follows: first, the core 1 is fixed by the heat shrink tape 9, and then the flame-retardant glass angle steel 10 is installed at the four corners of the core 1, and then the NHN flame-retardant insulating layer is wrapped, and finally the coil 11 is installed.

[0033] The outer part of the limiting screw 3 inside the clamp 2 is sleeved with an insulating sleeve, and the limiting screw 3 between the clamp 2 and the nut 4 is sleeved with an insulating end ring 5. Holes are punched at corresponding positions of the iron core 1 and the clamp 2, and then the limiting screw 3, the nut 4 and the insulating end ring 5 are installed to perform a fixing operation, which further clamps the iron core 1, thereby reducing the generation of noise. The limiting screw 3 and the nut 4 are both made of 304 stainless steel, which can effectively prevent leakage flux and also improve the performance of salt spray release. A terminal block 6 for output and input current is installed at the top of the clamp 2, and a guard plate 7 is installed at the top of the clamp 2 outside the terminal block 6. The guard plate 7 is arranged on the outermost side to prevent the staff from accidentally touching the terminal block 6. A lifting ring 15 is also distributed at the top of the clamp 2 to facilitate the overall energy-saving lifting operation.

[0034] An air duct 8 is arranged between the clamp 2 and the iron core 1, and a gap is arranged between the iron core 1 and the NHN flame retardant insulation layer around the flame retardant glass angle steel 10, and the gap is connected to the air duct 8, so that the heat dissipation airflow can enter the periphery of the iron core 1 through the air duct 8, and then pass through the gap between the iron core 1 and the NHN flame retardant insulation layer and the two sides of the I-beam 12, thereby performing efficient heat dissipation operation on the iron core 1 and the coil 11.

[0035] A base plate 13 is installed at the bottom end of the clamp 2, and a gasket 14 is arranged between the base plate 13 and the clamp 2. A hard plastic block is arranged inside the gasket 14, and a rubber sheet is wrapped outside the hard plastic block, and a silicone plate is wrapped outside the rubber sheet. The arrangement of the gasket 14 makes the clamp 2 and the base plate 13 have soft contact, so that when the base plate 13 is subjected to vibration, the vibration is transmitted through the gasket 14, resulting in less impact on the clamp 2, thereby achieving a certain anti-vibration effect.

[0036] The core 1 is made of non-oriented silicon steel sheets, and the non-oriented silicon steel sheets adopt a full-slant process. The oriented silicon steel sheets are low-cost, thereby effectively reducing the production cost of the transformer, and the full-slant process reduces the current loss by 3%-5%.

[0037] The inside of the coil 11 is copper wire, and the outside of the copper wire is first wrapped with two layers of imide film and then wrapped with two layers of glass fiber. The specific processing steps are: conductor (copper, aluminum) - film wrapping - painting - glass fiber wrapping - painting - baking - dipping - glass fiber wrapping - dipping - drying - product winding - inspection - storage, the specific process is as follows:

[0038] Step 1: Check whether the conductor used meets the standard requirements. Only qualified ones can be put into production;

[0039] Step 2: Pull the qualified conductor to the film wrapping head, stop the machine, install the film and stick it;

[0040] Step 3: Start the machine and pull the wire end to the first winding head of the glass fiber, stop the machine, install the glass fiber group, and add the corresponding insulating paint to the first and second paint cylinders;

[0041] Step 4: Start the machine, bake the wire end once, and then pull it to the second winding head of the glass fiber. Stop the machine, install the glass fiber group, and add the corresponding insulating paint to the third and fourth paint cylinders;

[0042] Step 5: Start the machine, dry the thread ends several times, and pull them to the take-up point. Then stop the machine for the first product inspection. Only qualified ones can be loaded for production;

[0043] Step 6: Place qualified products on product circulation cards and wait for inspection before storage.

[0044] By processing the copper wire used through the above steps, the coil has the characteristics of high voltage resistance between turns, good flame retardancy, and strong resistance to salt spray corrosion, thereby ensuring the stable operation of the coil and extending its service life.

[0045] The process of anti-corrosion treatment of the iron core 1 and the coil 11 is as follows:

[0046] Step 1: pre-baking the iron core 1 and the coil 11; the pre-baking temperature is 120-140° C., and the time is 2-4 hours;

[0047] Step 2: Cooling of the core 1 and coil 11: When dipping in resin, the temperature of the workpiece is cooled to <50℃; the viscosity of the resin needs to be controlled regularly, and the viscosity of the resin should be controlled at <150s23±2℃, 4# cup. When the viscosity of the resin is too high, use new resin or diluent to adjust it to 100~120s23±2℃, apply 4# cup. When there are sediments and particles in the resin, it is necessary to filter it with a 80~120 mesh screen before use.

[0048] Step 3: Vacuum pressure impregnation: It is best to pre-stir 116HU for 15~20 minutes before impregnating the resin, place the iron core 1 and the coil 11 in the impregnation tank, lock the tank cover, evacuate the tank until the residual pressure vacuum degree is <400Pa, and maintain it for 15~30 minutes, transfer the resin to the liquid level 50~100mm higher than the part of the workpiece to be impregnated, maintain a vacuum of <1000Pa for 30 minutes, release the vacuum, pressurize to 0.4~0.6MPa, and maintain the pressure for 0.5~1h, release the pressure to 0.4Mpa, and return the resin.

[0049] Step 4: dripping resin: dripping resin for ≥60min after returning the resin or until there is no resin on the surface of the iron core 1 and the coil 11;

[0050] Step 5: Baking the iron core 1 and the coil 11: Baking at 140-160°C for 3-8 hours, when the hot insulation resistance is stable and the paint film is smooth and non-sticky. For workpieces with hot insulation resistance requirements, it should be ensured that the hot insulation resistance is continuously stable for 3 hours and greater than the specified value. The assembled iron core 1 and coil 11 are processed through the above steps to have very high corrosion resistance, thereby ensuring the stability and safety of operation and extending the service life.

[0051] The insulating sleeve is a silicone glass fiber sleeve, which is made by weaving alkali-free glass fiber yarn into a tube and then coating it with silicone and treating it at high temperature. Since the silicone glass fiber sleeve has good dielectric properties, self-extinguishing properties and softness, it ensures the insulation and corrosion resistance of the limit screw.

[0052] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An offshore wind power transmission dry-type transformer, comprising an iron core (1), a clamp (2) for fixing the iron core (1), and a coil (11) wound around the outside of the iron core (1). Features: The iron core (1) inside the coil (11) is wrapped with heat shrinkable tapes (9) distributed vertically, flame retardant glass angle steels (10) are installed at four corners of the iron core (1) outside the heat shrinkable tapes (9), and an NHN flame retardant insulation layer that completely wraps the iron core (1) is arranged outside the flame retardant glass angle steel (10), I-shaped struts (12) are distributed between the layers inside the coil (11), and a coil air duct that is connected vertically is arranged inside the coil (11) between two adjacent I-shaped struts (12), and an anti-corrosion treatment operation is performed on the iron core (1) and the coil (11) after assembly; The process of anti-corrosion treatment of the iron core (1) and the coil (11) is as follows: Step 1: pre-baking the iron core (1) and the coil (11); the pre-baking temperature is 120-140° C., and the time is 2-4 hours; Step 2: Cooling the iron core (1) and the coil (11): When the workpiece is dipped in resin, the temperature is cooled to less than 50°C; Step 3: Vacuum pressure impregnation: Stir 116HU for 15-20 minutes before impregnation with resin, place the iron core (1) and the coil (11) in the impregnation tank, lock the tank cover, evacuate until the residual pressure (vacuum degree) in the impregnation tank is <400Pa, and maintain it for 15-30 minutes, pour the resin until the liquid level is 50-100mm higher than the part of the workpiece to be impregnated, maintain the vacuum of <1000Pa for 30 minutes, release the vacuum, pressurize to 0.4-0.6MPa, and maintain the pressure for 0.5-1h, release the pressure to 0.4Mpa, and return the resin; Step 4: dripping resin: drip the resin for ≥ 60 minutes after the resin is returned or until there is no resin on the surface of the iron core (1) and the coil (11); Step 5: Baking the iron core (1) and the coil (11): Baking at 140-160°C for 3-8 hours until the hot insulation resistance is stable and the paint film is smooth and non-sticky. For workpieces with hot insulation resistance requirements, it should be ensured that the hot insulation resistance is continuously stable for 3 hours and greater than the specified value.

2. An offshore wind power transmission dry-type transformer according to claim 1, Features: The outer portion of the limiting screw (3) inside the clamp (2) is sleeved with an insulating sleeve, the limiting screw (3) between the clamp (2) and the nut (4) is sleeved with an insulating end ring (5), the top end of the clamp (2) is equipped with a wiring board (6) for outputting and inputting current, the top end of the clamp (2) outside the wiring board (6) is equipped with a protective plate (7), and the top end of the clamp (2) is also distributed with a lifting ring (15).

3. An offshore wind power transmission dry-type transformer according to claim 2, Features: An air duct (8) is provided between the clamp (2) and the iron core (1), a gap is provided between the iron core (1) around the flame-retardant glass angle steel (10) and the NHN flame-retardant insulation layer, and the gap is connected to the air duct (8).

4. The offshore wind power transmission dry-type transformer according to claim 1, Features: A bottom plate (13) is installed at the bottom end of the clamp (2), a gasket (14) is arranged between the bottom plate (13) and the clamp (2), a hard plastic block is arranged inside the gasket (14), a rubber sheet is wrapped outside the hard plastic block, and a silicone sheet is wrapped outside the rubber sheet.

5. The offshore wind power transmission dry-type transformer according to claim 1, Features: The iron core (1) is made of non-oriented silicon steel sheets, and the non-oriented silicon steel sheets are made using a full-slope process.

6. The offshore wind power transmission dry-type transformer according to claim 1, Features: The interior of the coil (11) is a copper wire, and the exterior of the copper wire is first wrapped with two layers of imide film and then wrapped with two layers of glass fiber. The specific processing steps are: conductor (copper, aluminum) - film wrapping - painting - glass fiber wrapping - painting - baking - varnishing - glass fiber wrapping - varnishing - drying - product winding - inspection - storage. The specific process is as follows: Step 1: Check whether the conductor used meets the standard requirements. Only qualified ones can be put into production; Step 2: Pull the qualified conductor to the film wrapping head, stop the machine, install the film and stick it; Step 3: Start the machine and pull the wire end to the first winding head of the glass fiber, stop the machine, install the glass fiber group, and add the corresponding insulating paint to the first and second paint cylinders; Step 4: Start the machine, bake the wire end once, and then pull it to the second winding head of the glass fiber. Stop the machine, install the glass fiber group, and add the corresponding insulating paint to the third and fourth paint cylinders; Step 5: Start the machine, dry the thread ends several times, and pull them to the take-up point. Then stop the machine for the first product inspection. Only qualified ones can be loaded for production; Step 6: Place qualified products on product circulation cards and wait for inspection before storage.

7. An offshore wind power transmission dry-type transformer according to claim 2, Features: The insulating sleeve is a silicone glass fiber sleeve, which is made by weaving alkali-free glass fiber yarn into a tube and then coating it with silicone resin and subjecting it to high-temperature treatment.

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