A 138kv voltage class fully insulated power transformer

Abstract

The utility model relates to a kind of 138kV voltage grade full insulation power transformer, belong to transformer technical field.The technical solution is: the inner side upper end and lower end of the voltage regulating winding are respectively provided with voltage regulating upper end inner side angle ring and voltage regulating lower end inner side angle ring;The outgoing line first end of the high-voltage winding is provided with high-voltage first-end head end circle, and the upper end insulation cylinder is arranged between the upper end of the voltage regulating winding and the high-voltage first-end head end circle;The outgoing line end of the high-voltage winding is provided with lower end insulation cylinder between the head end and the lower end of the voltage regulating winding.The utility model has the beneficial effects that: using overall set insulation structure, high-voltage winding first end 138kV voltage grade, using end radial outgoing line, meet the creepage distance from high-voltage winding first end to voltage regulating winding;High-voltage winding end voltage grade is 220kV, using radial outgoing line, meet insulation distance and creepage distance, manufacture 138kV voltage grade full insulation power transformer.

Description

Technical Field

[0001] This utility model relates to a 138kV voltage level fully insulated power transformer, belonging to the field of transformer technology. Background Technology

[0002] Currently, the main voltage levels of power transformers are 35kV, 66kV, 110kV, 220kV, 330kV, and 500kV. With technological advancements, user requirements for transformers are becoming increasingly diverse. However, the demand for transformers with special voltage levels is gradually increasing, especially for 138kV, 90MVA fully insulated power transformers. Due to potential oscillations, the high-voltage terminal and tap voltages are both 220kV. Existing technology does not exist for transformers of these voltage levels, necessitating entirely new design and manufacturing. Utility Model Content

[0003] The purpose of this utility model is to provide a 138kV voltage level fully insulated power transformer, which adopts an integrally packaged insulation structure. The voltage level of the high-voltage winding is 138kV at the beginning, and radial outgoing lines are used at the end to meet the creepage distance requirements from the beginning of the high-voltage winding (voltage 138kV) to the regulating winding (voltage 220kV). The voltage level of the high-voltage winding end is 220kV, and radial outgoing lines are used to meet the insulation distance and creepage distance requirements. This invention manufactures a 138kV voltage level fully insulated power transformer and solves the above-mentioned technical problems existing in the prior art.

[0004] The technical solution of this utility model is: A 138kV fully insulated power transformer comprises a low-voltage winding, a high-voltage winding, and a voltage regulating winding arranged sequentially from the inside out. The voltage regulating winding has an upper inner corner ring and a lower inner corner ring on its inner upper and lower sides, respectively. The high-voltage winding has a high-voltage head-out end ring at its output end, and an upper insulating cylinder is provided between the upper end of the voltage regulating winding and the high-voltage head-out end ring. A lower insulating cylinder is provided between the output end of the high-voltage winding and the lower end of the voltage regulating winding. The output end of the high-voltage winding is wrapped with corrugated paper and insulated. Two high-voltage head-out end corner rings, one inside and one outside, are arranged outside the insulation of the high-voltage winding output end. A support strip is filled between the first high-voltage head-out end corner ring and the high-voltage winding output end. The high-voltage winding has an outer high-voltage head ring at its upper end and an outer high-voltage head-out end corner ring at its lower end.

[0005] Furthermore, the high-voltage winding is provided with a three-phase tap connection, which is connected to an on-load switch.

[0006] Furthermore, the low-voltage winding, high-voltage winding, and voltage-regulating winding are provided with lower yoke insulation between the lower yoke pad and the lower yoke pad, and the lower yoke pad is set on the support plate.

[0007] Furthermore, the upper end of the high-voltage winding and the voltage regulating winding is provided with an upper end ring of the high-regulation winding; the upper end ring of the high-regulation winding and the upper end of the low-voltage winding are provided with a pressure plate to press them together, and a pressure block is provided on the pressure plate.

[0008] The beneficial effects of this utility model are: it adopts an integral set insulation structure, the voltage level of the first end of the high voltage winding is 138kV, and the radial output of the end is adopted to meet the creepage distance from the first end of the high voltage winding (voltage 138kV) to the voltage regulating winding (voltage 220kV); the voltage level of the end of the high voltage winding is 220kV, and the radial output of the end is adopted to meet the insulation distance and creepage distance, thus manufacturing a 138kV voltage level fully insulated power transformer. Attached Figure Description

[0009] Figure 1 This is a schematic diagram of the overall assembly of this utility model embodiment; Figure 2 This is a schematic diagram of the high-voltage terminal outlet of an embodiment of this utility model; Figure 3 This is a front view of the high-voltage lead assembly according to an embodiment of the present invention; Figure 4 This is a top view of the high-voltage lead assembly according to an embodiment of the present invention; Figure 5 This is a side view of the high-voltage lead assembly according to an embodiment of the present invention; In the diagram: 1. Low-voltage winding; 2. High-voltage winding; 3. Regulating winding; 4. Inner corner ring at the upper end of the regulating winding; 5. Outer corner ring at the high-voltage winding; 6. Corner ring at the high-voltage winding end (first); 7. Corner ring at the high-voltage winding end (second); 8. Support bar; 9. Outer corner ring at the high-voltage winding end; 10. Lower yoke insulation at the lower end of the winding; 11. Lower yoke pad; 12. Support plate; 13. Upper end ring of the high-voltage regulating winding; 14. Pressure plate (first); 15. Pressure block (second); 16. Upper insulating cylinder; 17. Inner corner ring at the lower end of the regulating winding; 18. Lower insulating cylinder; 19. Transformer body centerline; 20. Tank centerline; 21. Outgoing line start; 22. Phase A tap; 23. Phase B tap; 24. Phase C tap; 25. Phase B end; 26. Phase C end; 27. On-load tap changer; 28. Detailed Implementation

[0010] The present invention will be further described below with reference to the accompanying drawings and examples.

[0011] See attached document Figure 1-5A 138kV fully insulated power transformer includes a low-voltage winding 1, a high-voltage winding 2, and a voltage regulating winding 3 arranged sequentially from the inside out. The upper and lower ends of the voltage regulating winding 3 are respectively provided with an upper voltage regulating inner corner ring 4 and a lower voltage regulating inner corner ring 18. The high-voltage winding 2 has a high-voltage head-out end ring 6 at its outgoing line end. An upper insulating cylinder 17 is provided between the upper end of the voltage regulating winding 3 and the high-voltage head-out end ring 6. The high-voltage winding 2 has an outlet end... A lower insulating cylinder 19 is provided between the lower end of the voltage regulating winding 3 and the lower end of the high voltage winding 2; the outlet end of the high voltage winding 2 is wrapped with corrugated paper and insulated, and the outlet end of the high voltage winding 2 is provided with a high voltage outlet corner ring 1 7 and a high voltage outlet corner ring 2 8 arranged inside and outside, and a support strip 9 is filled between the high voltage outlet corner ring 1 7 and the outlet end of the high voltage winding; the upper end of the high voltage winding 2 is provided with a high voltage winding outer corner ring 5, and the lower end of the high voltage winding 2 is provided with a high voltage outlet outer corner ring 10.

[0012] See attached document Figure 3 The high-voltage winding 2 is provided with a three-phase tap and is connected to the on-load switch 28.

[0013] See attached document Figure 1 The low-voltage winding 1, high-voltage winding 2 and voltage regulating winding 3 are provided with a lower yoke insulation 11 between the lower yoke pad 12 and the lower yoke pad 12. The lower yoke pad 12 is set on the support plate 13.

[0014] See attached document Figure 1 The high voltage winding 2 and the voltage regulating winding 3 are provided with a high-adjustment winding upper end ring 14 at the upper end; the high-adjustment winding upper end ring 14 and the low voltage winding 1 are provided with a pressure plate 15 for pressing, and a pressure block 16 is provided on the pressure plate 15.

[0015] See attached document Figure 5 The center line 21 of the oil tank is offset towards the low-voltage side relative to the center line 20 of the transformer body, and in this embodiment, the offset is 70mm. The B-phase and C-phase taps of the high-voltage winding run from the high-voltage side of the transformer and are run in two rows. The A-phase tap of the high-voltage winding runs from the low-voltage side of the transformer and is run in one row.

[0016] In this embodiment, the product model is SFZ-J-90000 / 138TH. Due to the large number of high-voltage taps, high voltage, and thick cables, the high-voltage taps are routed in double rows and single rows from both the high and low voltage sides of the transformer. The high-voltage lead assembly structure is reasonable. This utility model transformer is a fully insulated integrated structure with a 138 kV voltage at the high-voltage head and a 220 kV voltage level at the tail and taps. The high voltage is... *1%, due to potential oscillation, the voltage at the high-voltage end and tap line is 220kV.

[0017] like Figure 1As shown, this utility model increases the creepage distance between the beginning and end of the high-voltage winding 2 and the voltage regulating winding 3 by adding an upper inner corner ring 4 and a lower inner corner ring 18 to the inside of the voltage regulating winding 3, and an upper insulating cylinder 17 and a lower insulating cylinder 19 to the upper and lower ends of the voltage regulating winding 3; and by adding a high-voltage end exit corner ring 1 7, a high-voltage end exit corner ring 2 8 and a support bar 9 to the exit end of the high-voltage winding 2 to increase the creepage distance between the exit end of the high-voltage winding 2 and the yoke, thus meeting the requirements of 220kV and yoke creepage distance.

[0018] like Figure 2 As shown, the outlet end of the high voltage winding 2 is first wrapped with crepe paper, then with insulation, and then the corner ring 7 at the outlet end of the high voltage winding 2 and the outlet end of the high voltage winding 2 are filled with support strips 9.

[0019] like Figure 3-5 As shown, the high-voltage winding terminal outlet has a tap voltage of 220kV. To ensure insulation distance requirements, the tank centerline 21 is offset 70mm from the transformer body centerline 20 towards the low-voltage side. Due to the large number of three-phase taps, the B-phase tap 24 and C-phase tap 25 of the high-voltage winding run from the high-voltage side of the transformer in two rows, while the A-phase tap 23 of the high-voltage winding runs from the low-voltage side of the transformer in one row. This arrangement satisfies the insulation distance requirements and ensures smooth tap routing.

Claims

1. A 138kV fully insulated power transformer, characterized in that: The device comprises a low-voltage winding (1), a high-voltage winding (2), and a voltage-regulating winding (3) arranged sequentially from the inside out. The upper and lower ends of the voltage-regulating winding (3) are respectively provided with an upper voltage-regulating inner corner ring (4) and a lower voltage-regulating inner corner ring (18). The high-voltage winding (2) has a high-voltage head-out end ring (6) at its output end. An upper insulating cylinder (17) is provided between the upper end of the voltage-regulating winding (3) and the high-voltage head-out end ring (6). The output end of the high-voltage winding (2) is connected to the lower end of the voltage-regulating winding (3). A lower insulating cylinder (19) is provided between the ends; the outlet end of the high voltage winding (2) is wrapped with corrugated paper and insulated, and the outlet end of the high voltage winding (2) is provided with a high voltage outlet corner ring one (7) and a high voltage outlet corner ring two (8) arranged inside and outside, and a support strip (9) is filled between the high voltage outlet corner ring one (7) and the outlet end of the high voltage winding; the upper end of the high voltage winding (2) is provided with a high voltage winding outer corner ring (5), and the lower end of the high voltage winding (2) is provided with a high voltage outlet outer corner ring (10).

2. A 138kV fully insulated power transformer according to claim 1, characterized in that: The high-voltage winding (2) is provided with a three-phase tap and is connected to an on-load switch.

3. A 138kV fully insulated power transformer according to claim 1 or 2, characterized in that: The low-voltage winding (1), high-voltage winding (2) and voltage regulating winding (3) are provided with a lower yoke insulation (11) between the lower yoke pad (12) and the lower yoke pad (12). The lower yoke pad (12) is set on the support plate (13).

4. A 138kV fully insulated power transformer according to claim 1, characterized in that: The high voltage winding (2) and the voltage regulating winding (3) are provided with a high-adjustment winding upper end ring (14); the high-adjustment winding upper end ring (14) and the low voltage winding (1) are provided with a pressure plate (15) pressing them together, and a pressure block (16) is provided on the pressure plate (15).

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