35kV photovoltaic boosting transformer

Abstract

The 35kV photovoltaic boosting transformer comprises a transformer box, a high-voltage coil and a low-voltage coil are wound on an inner iron core of the transformer box, the high-voltage coil is provided with a head outgoing line outgoing from the upper portion, a tapping outgoing line outgoing from the middle and a tail outgoing line outgoing from the middle, and the tapping outgoing line is connected to a wire holder of a remote control switch. The head outgoing line is connected to the high-voltage bushing; the remote control switch is arranged above the front side of the transformer box, and the high-voltage bushing is mounted on the rear side surface, deviating from the remote control switch, of the transformer box; the low-voltage coil is provided with a head copper bar which is arranged upwards and a tail copper bar which is arranged downwards, the head copper bar is connected to a low-voltage sleeve through a lead bar, and the low-voltage sleeve is arranged at the vertical edge of the rear side surface of the transformer box; therefore, the high-voltage sleeve and the low-voltage sleeve are arranged on the box wall on the same side of the transformer, the remote control switch connected to the tapping outgoing line of the high-voltage coil is arranged on the opposite side face, assembly interference is effectively avoided, meanwhile, wiring operation is facilitated, and the overall space utilization rate is greatly improved.

Description

Technical Field

[0001] This invention relates to the field of transformer technology, and in particular to a 35kV photovoltaic step-up transformer. Background Technology

[0002] A photovoltaic (PV) power generation system is a renewable energy system that uses solar panels to directly convert solar energy into electrical energy. Its core equipment includes PV modules, inverters, and transformers. The main function of a PV transformer is to step up the low-voltage AC power output from the inverter to the grid voltage level, enabling safe grid connection. In PV power generation systems, transformers are typically integrated with high-voltage switching equipment and low-voltage distribution equipment into a PV transformer substation. Therefore, the transformer needs to be compact in size and equipped with appropriate bushing structures.

[0003] The 35kV step-up transformer is a key piece of equipment connecting distributed power sources and the main power grid, and is especially suitable for photovoltaic power generation systems.

[0004] Existing 35kV step-up transformers typically have high and low voltage bushings on both sides of the enclosure cover, along with high and low voltage leads on both sides, to prevent interference between the high and low voltage levels and ensure normal operation. However, integrating existing 35kV step-up transformers into photovoltaic transformer substations would increase the overall size of the enclosure, and the bushing and wiring layout would not meet the requirements for integrated use in photovoltaic transformer substations. Summary of the Invention

[0005] To address the aforementioned issues, this application provides a structurally sound 35kV photovoltaic step-up transformer, which effectively avoids assembly interference while facilitating wiring operations and significantly improving overall space utilization.

[0006] The technical solution adopted in this invention is as follows: A 35kV photovoltaic step-up transformer includes a transformer box. A high-voltage coil and a low-voltage coil are wound on the iron core of the transformer box. The high-voltage coil has a head wire exiting from the top, a tap wire exiting from the middle, and a tail wire exiting from the middle. The tap wire is connected to the terminal block of a remote control switch, and the head wire is connected to a high-voltage bushing. The remote control switch is located on the upper front side of the transformer box, and the high-voltage bushing is installed on the rear side of the transformer box, away from the remote control switch. The low-voltage coil has an upward-facing head copper busbar and a downward-facing tail copper busbar. The head copper busbar is connected to the low-voltage bushing via a lead busbar, and the low-voltage bushing is located at the vertical edge of the rear side of the transformer box.

[0007] As a further improvement to the above technical solution: The high-voltage bushings are horizontally spaced on the rear side of the transformer box, and the low-voltage bushings are vertically spaced on the rear side of the transformer box; both the high-voltage bushings and the low-voltage bushings are arranged laterally outward perpendicular to the rear side of the transformer box.

[0008] The transformer box extends outward to form a low-voltage box, and the rear side of the low-voltage box is flush with the rear side of the transformer box. The low-voltage coil is vertically arranged in the low-voltage box.

[0009] The remote control switch is supported and installed on the front side of the upper clamp at the front of the iron core, and the lead busbar connected to the low voltage coil is supported and installed on the rear side of the upper clamp at the rear of the iron core.

[0010] Corner plates are installed at intervals on the upper clamp, with the inner corners of each corner plate facing the upper clamp. The remote control switch is fixedly installed on the front side of the corner plate on the front upper clamp. A vertical plate is installed on the rear side of the corner plate on the rear upper clamp, and a lead wire bar is installed on the outer side of the vertical plate via a wire clamp.

[0011] The high-voltage coil is made of flat copper wire and consists of two sections of coil separated by insulated end rings. The first lead-out wire comes out from the upper section of the coil, and multiple tap leads are drawn out from the upper and lower sections of the coil respectively. The last lead-out wire comes out from the lower section of the coil. All tap leads are located on the same side, while the first and last leads are located on opposite sides of the tap leads.

[0012] The adjacent taps of the upper coil and the adjacent taps of the lower coil form an integer number of turns. The first tap of the upper coil and the corresponding tap form a fractional number of turns ending with 0.5 turns. The last tap of the lower coil and the corresponding tap form a fractional number of turns ending with 0.5 turns.

[0013] The low-voltage coil is wound with copper foil, and copper busbars are welded to the beginning and end of the copper foil to form the beginning and end copper busbars. The beginning copper busbar includes a phase a copper busbar with a lower height and phase b and phase c copper busbars with the same height. The low-voltage bushing is arranged close to the phase a copper busbar and far away from the phase c copper busbar. The lead busbar includes a phase a lead busbar connected to the phase a copper busbar, a phase b lead busbar connected to the phase b copper busbar, and a phase c lead busbar connected to the phase c copper busbar. The phase a lead busbar, phase b lead busbar, and phase c lead busbar are arranged staggered in space. The ends of each lead busbar are connected to the corresponding low-voltage bushing via connecting pieces.

[0014] The phase a lead busbar and phase b lead busbar both adopt a straight-line combined with downward vertical copper busbar structure, while the phase c lead busbar adopts an S-shaped combined with upward vertical copper busbar structure. The vertical lines in each copper busbar structure are connected to the corresponding low-voltage bushing via connecting pieces; the connecting pieces are L-shaped.

[0015] The tail copper busbars of each low-voltage coil are connected by two horizontal copper busbars to form a triangular connection. One horizontal copper busbar is a straight line structure, and the other horizontal copper busbar is a zigzag copper busbar.

[0016] Compared with the prior art, the present invention has the following beneficial effects: This invention places the high-voltage bushing and low-voltage bushing on the same side wall of the transformer, and places the remote control switch connected to the high-voltage coil tap line on the opposite side, achieving a reasonable and optimized layout for the 35kV step-up transformer. It is especially suitable for photovoltaic power generation systems. While effectively avoiding assembly interference and ensuring insulation performance, it facilitates wiring operations, minimizes the size of the transformer, especially the height, and greatly improves the overall space utilization, taking into account both the practicality and aesthetics of the 35kV step-up transformer. The present invention also includes the following advantages: The remote control switch is mounted on the upper clamp at the front of the iron core, which effectively utilizes the existing space of the transformer without occupying additional upper space. Combined with the tap outlet of the high voltage coil from the middle, it takes into account the wiring space and facilitates wiring operations.

[0017] By dividing the high-voltage coil into upper and lower sections and adopting a middle-outlet design, the interlayer voltage is effectively reduced, the interlayer insulation is reduced, and the outgoing and wiring operations are facilitated. Attached Figure Description

[0018] Figure 1 This is a top view of the present invention (lead busbar and low-pressure bushing omitted).

[0019] Figure 2 This is a front view schematic diagram of the present invention.

[0020] Figure 3 This is a rear view diagram of the present invention.

[0021] Figure 4 This is a schematic diagram of the high-voltage coil of the present invention.

[0022] Figure 5 This is a schematic diagram of the lead wires of the high-voltage coil of the present invention.

[0023] Figure 6 This is a schematic diagram of the lead wires of the low-voltage coil of the present invention.

[0024] Figure 7 This is a schematic diagram of the assembly of the corner plate and the vertical plate of the present invention.

[0025] Figure 8 This is a schematic diagram of the lead busbar structure of the present invention.

[0026] Figure 9 This is a schematic diagram of the structure of the zigzag copper busbar of the present invention.

[0027] The components include: 1. Transformer box; 2. Upper clamp; 21. Lower clamp; 3. Remote control switch; 31. Terminal block; 4. Corner plate; 5. Low-voltage box; 6. High-voltage bushing; 7. High-voltage coil; 8. Low-voltage coil; 9. Low-voltage bushing. 11. Channel steel; 12. U-shaped plate; 41. Vertical board; 71. First exit wire; 72. Tap exit wire; 73. Last exit wire; 74. Insulating end ring; 81. First copper busbar; 811. Phase a copper busbar; 812. Phase b copper busbar; 813. Phase c copper busbar; 82. Tail-end copper busbar; 83. Phase A lead busbar; 84. Phase C lead busbar; 85. Phase B lead busbar; 86. Connecting piece; 87. Z-shaped copper busbar. Detailed Implementation

[0028] The specific embodiments of the present invention will now be described with reference to the accompanying drawings.

[0029] like Figure 1 , Figure 2 and Figure 3 As shown, a 35kV photovoltaic step-up transformer of this embodiment includes a transformer box 1, on which a high-voltage coil 7 and a low-voltage coil 8 are wound. Figure 4 and Figure 5 As shown, the high-voltage coil 7 is equipped with a head wire 71 exiting from the top, a tap wire 72 exiting from the middle, and a tail wire 73 exiting from the middle. The tap wire 72 is connected to the terminal block 31 of the remote control switch 3, and the head wire 71 is connected to the high-voltage bushing 6. The remote control switch 3 is located on the upper front side of the transformer box 1, and the high-voltage bushing 6 is installed on the rear side of the transformer box 1 opposite to the remote control switch 3. Figure 6 As shown, the low-voltage coil 8 is provided with an upward-facing head copper busbar 81 and a downward-facing tail copper busbar 82. The head copper busbar 81 is connected to the low-voltage bushing 9 via a lead busbar. The low-voltage bushing 9 is located at the vertical edge of the rear side of the transformer box 1.

[0030] In this embodiment, the high-voltage bushing 6 and the low-voltage bushing 9 are arranged on the same side wall of the transformer, and the remote control switch 3 connected to the tap line 72 of the high-voltage coil 7 is arranged on the opposite side, so as to realize a reasonable and optimized layout of the 35kV step-up transformer, which is especially suitable for photovoltaic power generation systems.

[0031] High-voltage bushings 6 are horizontally spaced on the rear side of transformer box 1, and low-voltage bushings 9 are vertically spaced on the rear side of transformer box 1. Both high-voltage bushings 6 and low-voltage bushings 9 are arranged laterally outward perpendicular to the rear side of transformer box 1, which realizes a reasonable, optimized and reliable arrangement and installation of high-voltage bushings 6 and low-voltage bushings 9 on the same side of transformer box 1, and is especially convenient for the installation of low-voltage box 5 on transformer box 1.

[0032] The transformer box 1 extends outward from the side to form a low-voltage box 5. The rear side of the low-voltage box 5 is flush with the rear side of the transformer box 1. The low-voltage coil 8 is vertically arranged in the low-voltage box 5.

[0033] In this embodiment, a detachable panel can be installed on the low-pressure box 5 by sealing with a sealing strip. After the panel is removed, the operator can reach into the low-pressure box 5 to install the low-pressure sleeve 9, which facilitates assembly and maintenance operations.

[0034] The remote control switch 3 is supported and installed on the front side of the upper clamp 2 at the front of the iron core, and the lead busbar connected to the low voltage coil 8 is supported and installed on the rear side of the upper clamp 2 at the rear of the iron core.

[0035] In this embodiment, the remote control switch 3 is supported and installed on the upper clamp 2 at the front of the iron core, which effectively utilizes the existing space of the transformer without occupying additional upper space. Combined with the tap line 72 that leads out from the middle of the high voltage coil 7, the axial distance of the tap line 72 is longer, thus effectively taking into account the wiring space and facilitating wiring operations.

[0036] Corner plates 4 are installed at intervals on the upper clamp 2. The inner corners of each corner plate 4 are arranged and installed facing the upper clamp 2. The remote control switch 3 is fixedly installed on the front side of the corner plate 4 on the upper clamp 2. A vertical plate 41 is installed on the rear side of the corner plate 4 on the upper clamp 2. The lead wire is installed on the outer side of the vertical plate 41 through the wire clamp.

[0037] In this embodiment, as Figure 7 As shown, the vertical plate 41 is used to expand the capacity and facilitate the fixing of the wire clamp.

[0038] In this embodiment, wire clamps of different thicknesses can be used to adapt and install the vertical plate 41 and the corresponding lead busbar according to actual needs.

[0039] The high-voltage coil 7 is made of flat copper wire and consists of two sections of coil separated by an insulating end ring 74. The first lead-out line 71 comes out from the upper section of the coil, and multiple tap leads 72 are led out from the upper and lower sections of the coil respectively. The last lead-out line 73 comes out from the lower section of the coil. All tap leads 72 are located on the same side, while the first lead-out line 71 and the last lead-out line 73 are located on opposite sides of the tap leads 72.

[0040] In this embodiment, by dividing the high-voltage coil into upper and lower sections and adopting a middle-outlet design, the interlayer voltage is effectively reduced, the interlayer insulation is reduced, and the wiring and connection operations are facilitated.

[0041] The adjacent taps 72 of the upper coil and the adjacent taps 72 of the lower coil form an integer number of turns. The first tap 71 of the upper coil and its corresponding tap 72 form a fractional number of turns ending with 0.5 turns. The last tap 73 of the lower coil and its corresponding tap 72 form a fractional number of turns ending with 0.5 turns. This ensures that the taps 72, the first tap 71, and the last tap 73 in the high-voltage coil 7 are located on different sides and opposite to each other. Figure 1In the embodiment shown, the tap line 72 is located on the front side of the transformer for easy connection to the remote control switch 3, while the first tap line 71 and the last tap line 73 are located on the rear side of the transformer.

[0042] exist Figure 5 In the embodiment shown, the upper and lower sections of the high-voltage coil 7 are each provided with three taps 72. To satisfy the condition that the taps 72 are located on different and opposite sides of the first and last taps 71 and the last tap 73, the adjacent taps 72 form an integer number of turns, and the taps 72 and the first and last taps 71 and the last tap 73 form fractional turns ending with 0.5 turns. This ensures that the number of turns in both the upper and lower sections of the coil is a fractional turn ending with 0.5 turns.

[0043] In progress Figure 5 When the high-voltage coil 7 is wound, a first lead wire 71 is produced before the upper section of the coil is wound. When the last two layers are wound, X6, X4, and X2 branch leads 72 are produced. There are integer turns between the three branch leads 72, and there are fractional turns ending in 1 / 2 between the branch leads 72 and the first lead wire 71. Similarly, when the lower section of the coil is wound, the X3, X5, and X7 branch leads 72 are wound first, and the direction of the branch leads 72 of the upper section of the coil is consistent with that of the branch leads 72 of the upper section of the coil. There are integer turns between the three branch leads 72, and there are fractional turns ending in 1 / 2 between the branch leads 72 and the last lead wire 73.

[0044] The low-voltage coil 8 is wound with copper foil, and the copper foil is welded to copper busbars at both ends to form a head copper busbar 81 and a tail copper busbar 82. The head copper busbar 81 includes a lower a-phase copper busbar 811 and a b-phase copper busbar 812 and a c-phase copper busbar 813 of the same height. The low-voltage bushing 9 is arranged close to the a-phase copper busbar 811 and far away from the c-phase copper busbar 813. The lead busbars include a-phase lead busbar 83 connected to the a-phase copper busbar 811, b-phase lead busbar 85 connected to the b-phase copper busbar 812, and c-phase lead busbar 84 connected to the c-phase copper busbar 813. The a-phase lead busbar 83, b-phase lead busbar 85, and c-phase lead busbar 84 are arranged staggered in space. The ends of each lead busbar are connected to the corresponding low-voltage bushing 9 via connecting pieces 86 to realize the connection between the low-voltage coil 8 and the low-voltage bushing 9, which satisfies the arrangement and installation of the low-voltage bushing 9 on the transformer box 1.

[0045] Both phase a lead busbar 83 and phase b lead busbar 85 adopt a straight-line combined downward vertical copper busbar structure. Since the phase a copper busbar 811 and phase b copper busbar 812 have different heights, their straight-line combined downward vertical copper busbar structure will not cause interference. Phase c lead busbar 84 adopts an S-shaped combined upward vertical copper busbar structure. The S-shaped arrangement makes phase c lead busbar 84 spatially offset from phase b lead busbar 85 in the front-back direction.

[0046] In this embodiment, the a-phase lead busbar 83 and the b-phase lead busbar 85 are staggered in height and are arranged vertically downwards at their ends, while the c-phase lead busbar 84, which is at the same height as the b-phase lead busbar 85, is arranged vertically upwards at its end. This results in the ends of the a-phase lead busbar 83, the b-phase lead busbar 85, and the c-phase lead busbar 84 being staggered in height and arranged vertically.

[0047] The vertical rows in each copper busbar structure are connected to the corresponding low-voltage bushings 9 via connecting pieces 86. The connecting pieces 86 are L-shaped and can be of different sizes depending on the actual situation, so that the ends of each lead busbar can be connected to the corresponding low-voltage bushings 9 arranged in an orderly manner via the connecting pieces 86.

[0048] exist Figure 8 In the illustrated embodiment, the front view and top view of phase c lead bar 84, phase b lead bar 85, and phase a lead bar 83 are shown from top to bottom, which can be matched with Figure 3 The layout and use of [the equipment / system].

[0049] The tail copper busbars 82 of each low-voltage coil 8 are of the same length. The tail copper busbars 82 are connected in a triangular configuration using two transverse copper busbars to effectively reduce resistance imbalance. One transverse copper busbar has a straight-line structure, while the other is a V-shaped copper busbar 87. Figure 9 As shown.

[0050] In this embodiment, the openings on both sides of the U-shaped copper busbar 87 are connected to the tail copper busbar 82 of phases a and c, respectively, but are not connected to the tail copper busbar 82 of phase b.

[0051] In this embodiment, the transformer core is fixed using an upper clamp 2 combined with a lower clamp 21. To improve the fixing effect between the transformer core and the transformer box 1, a channel steel 11 can be installed between one end of the front and rear upper clamps 2, and a U-shaped plate 12 can be installed between the other ends. The channel steel 11 is fixed to the core using the tie rods and side bolts on the core assembly. At the same time, a fixing plate is welded to the corresponding position in the transformer box 1, and the fixing plate is bolted to the channel steel 11 and the U-shaped plate 12. Several 1mm and 2mm cardboard sheets are used to adjust the distance. The channel steel 11 can be bolted to an L-shaped plate first, and then connected to the fixing plate on the box wall through the L-shaped plate. The paint is removed from the opening to improve the grounding effect.

[0052] This invention achieves a reasonable and optimized layout for a 35kV step-up transformer, which is particularly suitable for photovoltaic power generation systems. It effectively avoids assembly interference and ensures insulation performance while facilitating wiring operations. It minimizes the size of the transformer, especially its height, greatly improving the overall space utilization and balancing the practicality and aesthetics of the 35kV step-up transformer.

[0053] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0054] The above description is an explanation of the present invention and not a limitation thereof. The scope of the present invention is defined by the claims. Within the scope of protection of the present invention, any form of modification may be made.

Claims

1. A 35kV photovoltaic step-up transformer, comprising a transformer box (1), wherein a high-voltage coil (7) and a low-voltage coil (8) are wound on the iron core of the transformer box (1), characterized in that: The high-voltage coil (7) is provided with a head wire (71) from the top, a branch wire (72) from the middle, and a tail wire (73) from the middle. The branch wire (72) is connected to the terminal block (31) of the remote control switch (3), and the head wire (71) is connected to the high-voltage bushing (6). The remote control switch (3) is located above the front side of the transformer box (1), and the high-voltage bushing (6) is installed on the rear side of the transformer box (1) away from the remote control switch (3). The low-voltage coil (8) is provided with a head copper busbar (81) facing upward and a tail copper busbar (82) facing downward. The head copper busbar (81) is connected to the low-voltage bushing (9) via a lead busbar. The low-voltage bushing (9) is located at the vertical edge of the rear side of the transformer box (1).

2. The 35kV photovoltaic step-up transformer as described in claim 1, characterized in that: The high-voltage bushings (6) are horizontally spaced on the rear side of the transformer box (1), and the low-voltage bushings (9) are vertically spaced on the rear side of the transformer box (1); the high-voltage bushings (6) and the low-voltage bushings (9) are both arranged laterally outward perpendicular to the rear side of the transformer box (1).

3. A 35kV photovoltaic step-up transformer as described in claim 1, characterized in that: The transformer box (1) extends outward to form a low-voltage box (5). The rear side of the low-voltage box (5) is flush with the rear side of the transformer box (1). The low-voltage coil (8) is vertically arranged in the low-voltage box (5).

4. A 35kV photovoltaic step-up transformer as described in claim 1, characterized in that: The remote control switch (3) is supported and installed on the front side of the upper clamp (2) at the front of the iron core, and the lead busbar connected to the low voltage coil (8) is supported and installed on the rear side of the upper clamp (2) at the rear of the iron core.

5. A 35kV photovoltaic step-up transformer as described in claim 4, characterized in that: Corner plates (4) are installed at intervals on the upper clamp (2). The inner corners of each corner plate (4) are arranged and installed facing the upper clamp (2). The remote control switch (3) is fixedly installed on the front side of the upper corner plate (4) of the upper clamp (2). A vertical plate (41) is installed on the rear side of the upper corner plate (4) of the upper clamp (2). A lead wire is installed on the outer side of the vertical plate (41) via a wire clamp.

6. A 35kV photovoltaic step-up transformer as described in claim 1, characterized in that: The high-voltage coil (7) is made of flat copper wire and consists of two sections of coil separated by an insulating end ring (74). The first lead (71) comes out from the upper section of the coil, and multiple tap leads (72) are drawn out from the upper section and the lower section of the coil, respectively. The last lead (73) comes out from the lower section of the coil. All tap leads (72) are located on the same side, while the first lead (71) and the last lead (73) are located on opposite sides of the tap leads (72).

7. A 35kV photovoltaic step-up transformer as described in claim 6, characterized in that: The adjacent taps (72) of the upper coil and the adjacent taps (72) of the lower coil form an integer number of turns. The first tap (71) of the upper coil and the corresponding tap (72) form a fractional number of turns ending with 0.5 turns. The last tap (73) of the lower coil and the corresponding tap (72) form a fractional number of turns ending with 0.5 turns.

8. A 35kV photovoltaic step-up transformer as described in claim 1, characterized in that: The low-voltage coil (8) is made of copper foil, and the copper foil is welded to copper busbars at the beginning and end to form a head copper busbar (81) and a tail copper busbar (82). The head copper busbar (81) includes a lower a-phase copper busbar (811) and a b-phase copper busbar (812) and a c-phase copper busbar (813) of the same height. The low-voltage bushing (9) is arranged close to the a-phase copper busbar (811) and far away from the c-phase copper busbar (813). The lead busbar includes an a-phase lead busbar (83) connected to the a-phase copper busbar (811), a b-phase lead busbar (85) connected to the b-phase copper busbar (812), and a c-phase lead busbar (84) connected to the c-phase copper busbar (813). The a-phase lead busbar (83), b-phase lead busbar (85), and c-phase lead busbar (84) are arranged staggered in space. The ends of each lead busbar are connected to the corresponding low-voltage bushing (9) via a connecting piece (86).

9. A 35kV photovoltaic step-up transformer as described in claim 8, characterized in that: The a-phase lead busbar (83) and the b-phase lead busbar (85) both adopt a straight-line combined with a downward vertical copper busbar structure, and the c-phase lead busbar (84) adopts an S-shaped combined with an upward vertical copper busbar structure. The vertical lines in each copper busbar structure are connected to the corresponding low-voltage bushing (9) via a connecting piece (86); the connecting piece (86) is an L-shaped structure.

10. A 35kV photovoltaic step-up transformer as described in claim 1, characterized in that: The tail copper busbar (82) of each low-voltage coil (8) is connected by two horizontal copper busbars to form a triangular connection. One of the horizontal copper busbars is a straight line structure, and the other horizontal copper busbar is a zigzag copper busbar (87).

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