Intermediate transformer high-voltage coil suitable for ultra-large-range voltage regulation
By adopting a continuous coil structure and optimized turn arrangement, the problems of short circuit between turns and insufficiency of traditional layer coils during the ultra-large range of pressure regulation are solved, and high-voltage coils of intermediate transformer with high strength, low cost and efficient heat dissipation are achieved.
Patent Information
- Application Number
- CN202421902709.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-07
- Publication Date
- 2025-07-18
- Estimated Expiration
- 2034-08-07
AI Technical Summary
During the process of ultra-large-range pressure regulation of traditional layer coils, the turns insulation is easily detached and damaged, resulting in short circuit between turns, instability and burning of the coil, and the width dimensions are difficult to control during winding, resulting in permanent deformation and insufficiency.
It adopts a continuous coil structure, supported by pads and straps, and uses wire winding of different widths and numbers to optimize the number of turns arrangement, improve the balance of the ampere turns, and control the amplitude dimension during the winding process, reducing weight and production costs.
The mechanical strength and short-circuit resistance of the coil are improved, the compactness and heat dissipation capacity during the winding process are ensured, and production costs and temperature rise risks are reduced.
Smart Images
Figure CN223123718U_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of intermediate transformer high-voltage coils, and specifically relates to an intermediate transformer high-voltage coil suitable for ultra-large range voltage regulation. Background Art
[0002] Combined with the leakage magnetic field, the analysis of the short-circuit electromotive force of the layer coil shows that at the minimum tapping, the tapping area does not participate in the operation, the ampere-turn distribution is extremely unbalanced, and the short-circuit current is the largest. The internal coil receives an inward annular pressure, and the external coil receives an outward annular tension. The wire is stretched, the coil diameter is expanded, and permanent deformation occurs. The turn insulation is also stretched and damaged, causing the inter-turn short-circuit coil to become unstable and burn. The ends of each layer of the layer coil are thin, usually only a few millimeters. Under the action of the axial electromotive force, the pressure per unit area is large, and it is easy to collapse and deform.
[0003] Traditional layer coil structure such as Figure 4 As shown, because the highest phase voltage reaches 21kV, the interlayer voltage is high and the interlayer insulation is thick, the radial dimension is difficult to control during the winding process and the winding is not tight. Utility Model Content
[0004] In order to solve the above problems, this paper proposes a high-voltage coil of an intermediate transformer suitable for ultra-large range voltage regulation, a plurality of tap terminals are arranged on the outside of the high-voltage coil, the tap terminals are vertically arranged and connected through a double-pancake continuous coil, the upper and lower end surfaces of the continuous coil are large-area support surfaces, the upper and lower end surfaces of the continuous coil are both annularly equidistantly provided with a plurality of pads, the continuous coil is uniformly and equidistantly provided with a plurality of support bars on the inner circumference, the upper and lower ends and the middle part of the continuous coil are separated by sub-turn coils, a continuous coil is provided between the sub-turn coils, the number of turns of the sub-turn coils is one-fourth of the number of turns of the continuous coil, and the sub-turn coils are provided with a plurality of spacers. The wire width used for the continuous coil inside the turn coil and the sub-turn coils at the upper and lower ends is greater than the wire width of the other continuous coils. The sub-turn coils are all wound with two wires in parallel, and have high mechanical strength and good processability through pads and stays. They can withstand large axial forces and have strong short-circuit resistance. Each line segment has a large heat dissipation capacity. During the winding process, the continuous coil is easier to control the radial size and ensure compactness. The sub-turn coil improves the ampere-turn balance of the overall coil. The wires used for winding the sub-turn coils and the wires used for winding the continuous coils use wires of different widths and different numbers, thereby conveniently reducing the weight of the overall coil, thereby reducing the production cost of the coil in disguise.
[0005] The shape of the spacer is a sector spacer. The width of the spacer is less than the radial width of the end of the continuous coil. The spacer is aligned with the support bar. The number of spacers is the same as the number of support bars. The shape of the support bar is a strip-shaped hard rod. The length of the support bar is the same as the height of the high-voltage coil. The number of support bars is the same as the number of spacers. The support bar is aligned with the spacer. A continuous coil is used. Each tap is composed of one or several double-pancake continuous coils. The end support surface of the continuous coil is large. In this project, the radial width of the end reaches 61 mm. The end ring consists of 12 spacers with a width of 40 along the circumference evenly distributed. The electromagnetic force received per unit area is less than 1 / 10 of that of the layer coil. There are 12 support bars evenly distributed along the circumference inside the radial direction. It has high mechanical strength, good processability, can withstand large axial forces, has strong short-circuit resistance, and each segment has a large heat dissipation capacity. During the winding process, it is easier to control the radial dimension of the continuous coil to ensure the tightness.
[0006] The tap terminals are arranged symmetrically up and down and staggered with each other, separated by the horizontal midline of the high-voltage coil and provided at the upper and lower ends. Double-pancake continuous coils are provided between the tap terminals. The sectional coils between the continuous coils are connected to the end branch lines at the upper and lower ends of the coil through the tap terminals. The sectional coils at both ends of the high-voltage coil are connected to the end branch lines at the upper and lower ends of the coil through the terminals at the upper and lower ends of the coil. To further improve the short-circuit resistance and the ampere-turn balance, the arrangement of the number of turns of the coil is optimized, and the ampere-turn balance degree is improved.
[0007] The continuous coil is wound and connected with a single wire. To optimize the cost, under the condition of ensuring safe operation and the temperature rise not exceeding the standard, different specifications of wires are selected for winding according to the current of different segments. Before the finished product is subjected to the temperature rise test, the optical fiber probes are respectively buried in the high-voltage coil. The measured temperature rise of the high-voltage winding is lower than the design value. There is no phenomenon of local overheating and the temperature rise exceeding the standard in the transformer.
[0008] Beneficial effects:
[0009] Through the spacer and the support bar, it has high mechanical strength, good processability, can withstand large axial forces, has strong short-circuit resistance, and each segment has a large heat dissipation capacity. During the winding process, it is easier to control the radial dimension of the continuous coil to ensure the tightness. The sectional coil improves the ampere-turn balance degree of the overall coil. The wires used for winding the sectional coil and the continuous coil, by using wires with different widths and different quantities, thus conveniently reduce the weight of the overall coil, and thereby indirectly reduce the production cost of the coil.
[0010] A continuous coil is adopted, and each tap is composed of one or several double-disc continuous coils. The end support surface of the continuous coil is large. In this project, the radial dimension at the end reaches 61 mm. The end coil consists of 12 pads with a width of 40 along the circumference evenly distributed. The electromagnetic force received per unit area is less than 1 / 10 of that of the layer coil. There are 12 spacers evenly distributed along the circumference inside the radial direction. It has high mechanical strength, good processability, can bear large axial forces, has strong short-circuit resistance, and each line segment has a large heat dissipation capacity. During the winding process, it is easier to control the radial dimension of the continuous coil to ensure the compactness.
[0011] To optimize the cost, while ensuring safe operation and the temperature rise not exceeding the standard, different specifications of wires are selected for winding according to the current of different segments. Before the finished product undergoes the temperature rise test, the optical fiber probes are respectively buried in the high-voltage coil. The measured temperature rise of the high-voltage winding is lower than the design value. No phenomenon of local overheating or excessive temperature rise occurs in the transformer. Brief Description of the Drawings
[0012] Figure 1 It is a coil structure diagram of the high-voltage coil of an intermediate transformer applicable to ultra-wide range voltage regulation;
[0013] Figure 2 It is a multi-row coil structure diagram of the high-voltage coil of an intermediate transformer applicable to ultra-wide range voltage regulation;
[0014] Figure 3 It is a schematic diagram of the wire types of the multi-row coil of the high-voltage coil of an intermediate transformer applicable to ultra-wide range voltage regulation;
[0015] Figure 4 It is a schematic diagram of the traditional layer coil structure. Detailed Description of the Preferred Embodiment
[0016] To deepen the understanding of the present invention, the present invention will be further described in detail below in conjunction with the embodiments and the drawings. The embodiments are only used to explain the present invention and do not constitute a limitation to the protection scope of the present invention.
[0017] As shown in Figure 1 、 2 、3;
[0018] An intermediate transformer high-voltage coil suitable for ultra-wide-range voltage regulation. A number of tapping terminals are provided on the outer side of the high-voltage coil. The tapping terminals are vertically arranged and connected by a double-winding continuous coil. The upper and lower end faces of the connected continuous coils are large-area supporting surfaces. A number of pads are provided on the upper and lower surfaces of the continuous coil in an annular and equidistant manner. A number of spacer bars are evenly arranged at equal intervals on the inner circumference in the radial direction of the continuous coil. The upper, lower ends and middle of the continuous coil are provided with sectional coils in a separated manner. Continuous coils are provided between the sectional coils. The number of turns of the sectional coil is one-fourth of the number of turns of the continuous coil. The wire widths of the sectional coils and the continuous coils inside the upper and lower end sectional coils are larger than the wire widths of the remaining continuous coils. The sectional coils are all wound in parallel with two wires. The shape of the pad is a sector-shaped pad. The width of the pad is smaller than the radial width of the end of the continuous coil. The pads are aligned with the spacer bars. The number of pads is the same as the number of spacer bars. The shape of the spacer bar is a strip-shaped hard rod. The length of the spacer bar is the same as the height of the high-voltage coil. The number of spacer bars is the same as the number of pads. The spacer bars are aligned with the pads. The tapping terminals are arranged symmetrically and staggeredly up and down with the horizontal center line of the high-voltage coil as the separator at the upper and lower ends. Double-winding continuous coils are provided between the tapping terminals. The sectional coils between the continuous coils are connected to the end branches at the upper and lower ends of the coil through the tapping terminals. The sectional coils at both ends of the high-voltage coil are connected to the end branches at the upper and lower ends of the coil through the terminals at the upper and lower ends of the coil. The continuous coil is wound and connected with a single wire.
[0019] Implementation example;
[0020] Because at the rated tap and the minimum tap, some coils do not participate in operation. Especially at the minimum tap, terminals 8 and 7 are connected, and all 600 turns in the middle are short-circuited and do not participate in operation. So at this time, relative to the low voltage, the high-voltage ampere-turns are unbalanced. To further improve the short-circuit resistance and improve the ampere-turn balance, we optimized the turn arrangement of the coil. As Figure 3 shown, take out 25 turns each from the 50 turns from A1 to terminal 8 and from terminal 7 to X1, and put them between terminal 6 to 2 and between terminal 1 to 5. At this time, when operating at the minimum tap, 50 turns participate in operation between terminals 8 and 7, improving the ampere-turn balance.
[0021] The current is the largest at the minimum tap, which is 111.1 amperes. Therefore, the segments participating in operation are: A1 - A1’, A1’ - 8, 7 - X1’, X1’ - X, a total of 100 turns, and are wound in parallel using 2 wires of 1.4×7.1; at the second - last and the third - last taps, the currents are 55.6 amperes and 37 amperes respectively, and are wound using 1 wire of 1.4×7.1; for the rated tap and the other taps, since the current is small, 15.9 - 27.8 amperes, they are wound using 1 wire of 1.4×5. By using the above - mentioned scheme, a total of 679 kg of wire is used for the high - voltage coil of this project.
[0022] If designed according to the traditional idea and using the same wire gauge, on the premise of ensuring that the temperature rise within each tap range does not exceed the standard, the whole coil can only be wound in parallel using 2 wires of 1.4×7.1. A total of about 1000 kg of wire is required, and the consumption is 47% more than the optimized scheme.
[0023] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.
Claims
1. An intermediate transformer high-voltage coil suitable for ultra-wide range voltage regulation, wherein a plurality of tapping terminals are arranged on the outer side of the high-voltage coil, and it is characterized in that, The tap terminals are vertically arranged and connected by a continuous coil of double pancakes. The upper and lower end faces of the connected continuous coils are large-area support surfaces. A number of pads are arranged on the upper and lower end surfaces of the continuous coil at equal circumferential intervals in a ring shape. A number of support bars are evenly arranged at equal intervals on the inner circumference in the radial direction of the continuous coil. The upper and lower ends and the middle part of the continuous coil are provided with sectional coils in a separated manner. Continuous coils are arranged between the sectional coils. The number of turns of the sectional coil is one-fourth of the number of turns of the continuous coil. The wire widths of the sectional coils and the continuous coils inside the upper and lower end sectional coils are larger than the wire widths of the remaining continuous coils. The sectional coils are all wound with two wires in parallel.
2. The high-voltage coil of an intermediate transformer applicable to ultra-large range voltage regulation according to claim 1, characterized in that, The shape of the pad is a sector-shaped pad. The width of the pad is smaller than the radial width of the end of the continuous coil. The pad is aligned with the support bar. The number of pads is the same as the number of support bars.
3. The high-voltage coil of an intermediate transformer applicable to ultra-large-range voltage regulation according to claim 1, wherein, The shape of the support bar is a strip-shaped hard rod. The length of the support bar is the same as the height of the high-voltage coil. The number of support bars is the same as the number of pads. The support bar is aligned with the pad.
4. The high-voltage coil of an intermediate transformer applicable to ultra-large range voltage regulation according to claim 1, characterized in that The tap terminals are arranged symmetrically and staggeredly up and down with the horizontal midline of the high-voltage coil as the separation and are provided at the upper and lower ends. Double-pancake continuous coils are arranged between the tap terminals.
5. An intermediate transformer high-voltage coil applicable to ultra-wide-range voltage regulation according to claim 1, characterized in that, The sectional coils between the continuous coils are connected to the end branch lines at the upper and lower ends of the coil through the tap terminals. The sectional coils at both ends of the high-voltage coil are connected to the end branch lines at the upper and lower ends of the coil through the terminals at the upper and lower ends of the coil.
6. The high-voltage coil of an intermediate transformer applicable to ultra-large range voltage regulation according to claim 1, wherein The continuous coil is wound and connected with a single wire.