Distribution transformer based on remote control switch

Abstract

The present invention belongs to the field of distribution transformers. Specifically disclosed is a distribution transformer based on a remote control switch. The distribution transformer comprises: a transformer tank, a three-phase winding disposed in the transformer tank, a tap changer disposed below the three-phase winding, an adjusting knob disposed on the transformer tank, bushings disposed above the transformer tank, and a fixing assembly disposed inside the transformer tank. The three-phase coil comprises an A-phase winding, a B-phase winding, and a C-phase winding, and the structures of the A-phase winding, the B-phase winding, and the C-phase winding are the same. Several tap leads are provided at a lead-out end of the A-phase winding, and the tap leads are electrically connected to the tap changer below the A-phase winding. The tap changer is electrically connected to the adjusting knob by means of a connecting wire. Compared with conventional distribution transformers having the same capacity, the present invention greatly reduces the height without changing the length and width of transformers, thereby reducing the overall volume of the transformers, minimizing the transformer size to the greatest extent, and reducing the consumption of steel, transformer oil, and copper.

Description

A distribution transformer based on a remote control switch Technical Field

[0001] This invention belongs to the field of power distribution transformer technology, and specifically relates to a power distribution transformer based on a remote control switch. Background Technology

[0002] In the current 10kV distribution transformer manufacturing industry, the high-voltage side tap changer of the transformer is generally fixed directly to the tank cover, with the high-voltage coil extending axially and clamped by wire clamps before being connected to the tap changer. This requires reserving space above the clamps for lead wire clamping and space for switch assembly, and the height of the low-voltage coil copper busbar must also be matched accordingly, increasing the amount of main transformer materials used.

[0003] However, in existing technology, a remote control switch has been introduced. This remote control switch connects to the tap changer via a connecting wire, allowing it to be installed outside the fuel tank. This means that the switch no longer needs to be fixed to the tank cover, and the gear position can still be adjusted. Furthermore, in existing technology, taking the A-phase coil as an example, the high-voltage coil of the A-phase coil has a total of 15 layers, with the output sequence being X6, X4, X2, X3, X5, X7, X. That is, the 14th layer outputs X6, X4, X2 sequentially from bottom to top. X3 can directly output from the upper part of the 15th layer. To enhance short-circuit resistance, the X2 and X3 terminals are reversed, with X3, X5, X7, X output starting from the lower part of the 15th layer. The high-voltage coil uses radial taps. The X6, X4, and X2 taps on the outermost layer occupy turns in the outermost layer (meaning the turns containing the outermost taps must be removed during the outermost coil winding). Additionally, the outermost taps require insulation, taking up space. Therefore, the outermost layer cannot be fully wound, requiring 5-6 turns. This results in an inefficient coil turn arrangement. The conventional transformer structure is no longer suitable for this type of remote-controlled switch, necessitating a low-cost transformer structure that is compatible with it. Summary of the Invention

[0004] This invention provides a distribution transformer based on a remote control switch, which solves the problem that the current transformer structure is not suitable for remote control switches and requires a large space.

[0005] To solve the above-mentioned technical problems, the technical solution of the present invention is: a distribution transformer based on a remote control switch, comprising: an oil tank, a three-phase coil disposed in the oil tank, a tap changer disposed below the three-phase coil, an adjustment knob disposed on the oil tank, a bushing disposed above the oil tank, and a fixing component disposed inside the oil tank.

[0006] The three-phase coil includes an A-phase coil, a B-phase coil, and a C-phase coil, and the A-phase coil, the B-phase coil, and the C-phase coil have the same structure.

[0007] The output terminal of the A-phase coil is provided with several tap leads, which are electrically connected to the tap switch below the A-phase coil; the tap switch is electrically connected to the adjustment knob via a connecting wire.

[0008] In a preferred embodiment of the present invention, the fixing component includes a high-pressure clamp and a fixing plate;

[0009] The high-pressure clamp is made of channel steel. The fixing plate is fixed to the high-pressure clamp. The fixing plate has a through hole and a nut is welded at the through hole. The nut is located on the side of the fixing plate close to the channel steel. The tap changer is fixedly connected to the fixing plate by bolts.

[0010] In a preferred embodiment of the present invention, the fixing assembly further includes a high-voltage upper clamp, a low-voltage upper clamp, and a steel tension strap. The high-voltage upper clamp is disposed on the high-voltage side of the three-phase coil, and the low-voltage upper clamp is disposed on the low-voltage side of the three-phase coil. One end of the steel tension strap is fixedly connected to the high-voltage upper clamp, and the other end is fixedly connected to the low-voltage upper clamp. The high-voltage upper clamp and the low-voltage upper clamp are arranged parallel to each other, and the steel tension strap is arranged perpendicular to both the high-voltage upper clamp and the low-voltage upper clamp.

[0011] In a preferred embodiment of the present invention, a pull strip insulation is provided between the steel pull strip and the yoke of the transformer, and the width of the pull strip insulation is greater than the width of the pull strip.

[0012] In a preferred embodiment of the present invention, the steel tension strip includes a first connecting section, a first ramp section, a horizontal section, a second ramp section, and a second connecting section. The steel tension strip is axially symmetrical along the central axis of the horizontal section, and the included angle between the first connecting section and the first ramp section is 132° to 138°.

[0013] In a preferred embodiment of the present invention, the fixing assembly further includes a horizontal lead copper busbar and a low-voltage coil copper busbar. The low-voltage coil copper busbar of the A-phase coil is electrically connected to the A-phase coil, the low-voltage coil copper busbar is electrically connected to the horizontal lead copper busbar, and the horizontal lead copper busbar is electrically connected to the bushing.

[0014] In a preferred embodiment of the present invention, the low-voltage coil copper busbar includes a first section, a second section perpendicular to the first section, and a third section perpendicular to the second section. The first section and the third section are located on both sides of the second section, and the third section is disposed inside the A-phase coil.

[0015] In a preferred embodiment of the present invention, the fixing component includes a high-pressure upper clamp, a low-pressure upper clamp, a high-pressure lower clamp, and a low-pressure lower clamp. The high-pressure upper clamp and the high-pressure lower clamp are fixedly connected by a pull screw, and the low-pressure upper clamp and the low-pressure lower clamp are fixedly connected by a pull screw.

[0016] In a preferred embodiment of the present invention, two side screws are also fixedly provided between the high-pressure upper clamp and the low-pressure upper clamp.

[0017] In a preferred embodiment of the present invention, the tap lead of the A-phase coil includes seven lead heads, namely X6, X4, X2, X3, X5, X7 and X. The A-phase coil includes 15 layers of coil wound sequentially from the inside out. The first to the 14th layers are connected end to end in sequence, and the 15th layer is not connected to the other layers. Lead heads X6, X4 and X2 are located on the 14th layer, and lead heads X3, X5, X7 and X are located on the 15th layer.

[0018] In a preferred embodiment of the present invention, the coil between the output terminals X4 and X2 is a tap section, the coil between the output terminals X3 and X5 is a tap section, and the remaining coils are normal sections; the cross-sectional area of ​​the conductor in the tap section is smaller than the cross-sectional area of ​​the conductor in the normal section.

[0019] In a preferred embodiment of the present invention, in the A-phase coil, the first and second layers each have 62 turns of coil wound, the third layer has 63 turns of coil wound, the fourth to thirteenth layers each have 64 turns of coil wound, the fourteenth layer has 66 turns of coil wound, and the fifteenth layer has 61 turns of coil wound.

[0020] The technical solution provided by this invention has the following advantages compared with the prior art:

[0021] Compared with conventional distribution transformers of the same capacity, this invention significantly reduces the height without changing the length and width of the transformer, making the transformer smaller and suitable for some scenarios where height is a requirement.

[0022] Furthermore, manufacturing costs are reduced by incorporating the switch into the lower clamp, minimizing transformer size, and reducing the use of steel, transformer oil, and copper. This effectively saves materials while maintaining product performance. The rational coordination and arrangement between the coils, core, and leads ensures convenience during transformer manufacturing and makes the transformer more compact and practical. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other embodiments can be obtained from these drawings without creative effort.

[0024] Figure 1 is a front view of a distribution transformer based on a remote control switch according to an embodiment of the present invention;

[0025] Figure 2 is a schematic diagram of the three-phase coil of a distribution transformer based on a remote control switch according to an embodiment of the present invention;

[0026] Figure 3 is a side view of a distribution transformer based on a remote control switch according to an embodiment of the present invention;

[0027] Figure 4 is a top view of a distribution transformer based on a remote control switch according to an embodiment of the present invention;

[0028] Figure 5 is a schematic diagram of a high-voltage clamping component of a distribution transformer based on a remote control switch according to an embodiment of the present invention.

[0029] Figure 6 is an assembly diagram of the high-voltage clamp and fixing plate of a distribution transformer based on a remote control switch according to an embodiment of the present invention.

[0030] Figure 7 is a schematic diagram of the steel strip of a distribution transformer based on a remote control switch according to an embodiment of the present invention;

[0031] Figure 8 is a front view of the low-voltage coil copper busbar of a distribution transformer based on a remote control switch according to an embodiment of the present invention.

[0032] Figure 9 is a side view of the low-voltage coil copper busbar of a distribution transformer based on a remote control switch according to an embodiment of the present invention.

[0033] Figure 10 is a schematic diagram of the horizontal lead copper busbar assembly of a distribution transformer based on a remote control switch according to an embodiment of the present invention.

[0034] Figure 11 is a schematic diagram of the three-phase coil wiring of a distribution transformer based on a remote control switch according to an embodiment of the present invention;

[0035] Figure 12 is a schematic diagram of the three-phase coil output of a distribution transformer based on a remote control switch according to an embodiment of the present invention;

[0036] Figure 13 is a schematic diagram of the A-phase coil output position of a distribution transformer based on a remote control switch according to an embodiment of the present invention.

[0037] Figure 14 is a schematic diagram of the A-phase coil segmentation of a distribution transformer based on a remote control switch according to an embodiment of the present invention.

[0038] The diagram shows: 10-oil tank; 20-three-phase coil; 201-A-phase coil; 2011-outlet terminal; 202-B-phase coil; 203-C-phase coil; 30-tap switch; 40-adjusting knob; 50-sleeve; 60-connecting wire; 701-high voltage lower clamp; 702-fixing plate; 703-high voltage upper clamp; 704-low voltage upper clamp; 705-steel pull strap; 7051-first connecting section; 7052-first ramp section; 7053-horizontal section; 7054-second ramp section; 7055-second connecting section; 706-pull strap insulation; 707-side screw; 708-pull screw; 709-horizontal lead copper busbar; 710-low voltage coil copper busbar; 7101-first section; 7102-second section; 7103-third section. Detailed Implementation

[0039] For ease of understanding, the following embodiments illustrate a distribution transformer based on a remote control switch. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention.

[0040] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation and positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0041] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0042] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.

[0043] As shown in Figures 1 and 2, a distribution transformer based on a remote control switch includes: an oil tank 10, a three-phase coil 20 disposed inside the oil tank 10, a tap changer 30 disposed below the three-phase coil 20, an adjustment knob 40 disposed on the oil tank 10, a bushing disposed above the oil tank 10, and a fixing component disposed inside the oil tank 10.

[0044] In this invention, the tap changer 30 is located below the three-phase coil 20, while the adjustment knob 40 is located above the oil tank 10. The two are connected by a connecting line 60, thus forming a remote control switch.

[0045] First, as shown in Figures 3 and 4, the fixing assembly includes a high-pressure upper clamp 703, a low-pressure upper clamp 704, a high-pressure lower clamp 701, and a low-pressure lower clamp.

[0046] As shown in Figure 1, the high-pressure upper clamp 703 and the high-pressure lower clamp 701 are fixedly connected by a pull screw 708, and the low-pressure upper clamp 704 and the low-pressure lower clamp are also fixedly connected by a pull screw 708. As shown in Figure 4, two side screws 707 are also fixedly installed between the high-pressure upper clamp 703 and the low-pressure upper clamp 704. The high-pressure upper clamp 703, the low-pressure upper clamp 704, the high-pressure lower clamp 701, and the low-pressure lower clamp are all fixed in pairs by pull screws 708 or side screws 707, which increases rigidity.

[0047] As shown in Figures 5 and 6, the fixing assembly also includes a fixing plate 702. The high-voltage clamp 701 is made of channel steel, and the fixing plate 702 is fixed to it. The fixing plate 702 is made of 4mm steel plate and has a through hole. A nut is welded to the through hole, and the nut is located on the side of the fixing plate 702 closest to the channel steel. The tap changer 30 is fixedly connected to the fixing plate 702 by bolts. During assembly, bolts can be directly passed through the switch support plate and the fixing plate 702 and screwed into the nut, eliminating the need for workers to tighten the nut from the inside. This solves the installation problem in confined spaces and makes full use of this space, keeping the transformer width constant.

[0048] As shown in Figure 4, the fixing assembly also includes a high-voltage upper clamp, a low-voltage upper clamp, a steel tension strap 705, and a cardboard. The high-voltage upper clamp is located on the high-voltage side of the three-phase coil 20, and the low-voltage upper clamp is located on the low-voltage side of the three-phase coil 20. One end of the steel tension strap 705 is fixedly connected to the high-voltage upper clamp 703, and the other end is fixedly connected to the low-voltage upper clamp 704. The high-voltage upper clamp 703 and the low-voltage upper clamp 704 are arranged parallel to each other, and the steel tension strap 705 is arranged perpendicular to the high-voltage upper clamp 703 and the low-voltage upper clamp 704.

[0049] A pull strap insulation 706 is installed between the steel pull strap 705 and the transformer yoke. The width of the pull strap insulation 706 is greater than the width of the pull strap. The yoke clamping structure utilizes the steel pull strap 705 and the side screw 707. Compared with conventional semi-dry glass adhesive tape, the steel pull strap 705 provides a better clamping effect and is less prone to deformation. The pull strap insulation 706 is placed between the pull strap 705 and the yoke, and the width of the pull strap insulation 706 is 20mm wider than the steel pull strap 705. If there is still a gap, it can be adjusted using 1mm cardboard.

[0050] As shown in Figure 7, the steel tension strip 705 includes a first connecting section 7051, a first ramp section 7052, a horizontal section 7053, a second ramp section 7054, and a second connecting section 7055. The steel tension strip 705 is axially symmetrical about the central axis of the horizontal section 7053. The angle between the first horizontal section 7053 and the first ramp section 7052 is 132° to 138°. In one embodiment of the present invention, the angle between the first horizontal section 7053 and the first ramp section 7052 is 135°. That is to say, the steel tension strip 705 in the present invention is designed as an arched structure, which has higher connection strength and a more stable structure.

[0051] As shown in Figures 8, 9 and 10, the fixing assembly also includes a horizontal lead copper busbar 709 and a low-voltage coil copper busbar 710. The A-phase coil 201 is electrically connected to the low-voltage coil copper busbar 710, the low-voltage coil copper busbar 710 is electrically connected to the horizontal lead copper busbar 709, and the horizontal lead copper busbar 709 is electrically connected to the bushing 50.

[0052] The low-voltage coil copper busbar 710 includes a first section 7101, a second section 7102 perpendicular to the first section 7101, and a third section 7103 perpendicular to the second section 7102. The first section 7101 and the third section 7103 are located on both sides of the second section 7102. The third section 7103 is inserted into the low-voltage side of the A-phase coil 201. Therefore, the low-voltage coil copper busbar 710 can also be considered as the output end of the low-voltage coil.

[0053] Referring to Figure 2, since the three-phase coil 20 includes phase A coil 201, phase B coil 202, and phase C coil 203, the structures of phase A coil 201, phase B coil 202, and phase C coil 203 are identical. Referring to Figure 11, phase A coil 201, phase B coil 202, and phase C coil 203 are connected in a D-connection.

[0054] Taking phase A coil 201 as an example, the output end of phase A coil 201 is provided with several tap leads, which are electrically connected to the tap switch 30 below phase A coil 201; the tap switch 30 is electrically connected to the adjustment knob 40 through the connecting wire 60.

[0055] Referring to Figure 1, the tap leads of phase A coil 201 include seven lead-out terminals 2011, namely X6, X4, X2, X3, X5, X7, and X. Referring to Figure 12, phase A coil 201 includes 15 layers of coil wound sequentially from the inside out. Layers 1 to 14 are connected end to end, and layer 15 is not connected to other layers. Lead-out terminals X6, X4, and X2 are located on layer 14, and lead-out terminals X3, X5, X7, and X are located on layer 15.

[0056] Referring to Figures 13 and 14, the coil between the lead wires X4 and X2 is a tap section, the coil between the lead wires X3 and X5 is a tap section, and the remaining coils are normal sections; the cross-sectional area of ​​the conductor in the tap section is smaller than that in the normal section.

[0057] In phase A coil 201, the first and second layers each have 62 turns of coil, the third layer has 63 turns of coil, the fourth to thirteenth layers each have 64 turns of coil, the fourteenth layer has 66 turns of coil, and the fifteenth layer has 61 turns of coil.

[0058] Specifically, taking phase A coil 201 as an example, the sequence of the high-voltage coil output terminals 2011 of phase A coil 201 is X6, X4, X2, X3, X5, X7, X, which means that the 14 layers output X6, X4, X2 in sequence from bottom to top.

[0059] Referring specifically to Figure 14, in this invention, the coil outlet is divided into a normal section and a tapped section. The tapped section uses a wire with a slightly smaller cross-sectional area, allowing the 14th layer to have 2 more turns and the 15th layer to have 2 fewer turns. To avoid affecting load loss (measured at the rated setting), the 45 turns between X4 and X2, and between X3 and X5, are tapped sections, while the rest are normal sections. This allows the outermost layer to have more turns while meeting axial dimensions, leaving space for the outermost layer. Furthermore, the high-voltage outlet sequence is consistent with the switch connector sequence.

[0060] The present invention typically includes the following steps in manufacturing its lead portion structure.

[0061] 1. The high-voltage lead should be laid horizontally downwards and securely tied with cable ties; no wire clamps are required.

[0062] 2. The high-voltage lead is a φ2.5 paper-insulated round copper wire. One end is connected to the original coil wire by welding, and the welded joint is wrapped with insulating paper. The other end is cold-pressed to the tap changer 30. The lead is inserted into the terminal until it extends halfway out of the terminal on the opposite side of the switch, and then pressed down with cold-pressing pliers to the maximum depth.

[0063] 3. The connecting wire 60 of the tap changer 30 is tied to the pull rods 708 on both sides, and tied twice on each side to fix it in place.

[0064] 4. The low-voltage coil copper busbar 710 of the low-voltage coil is improved, changing from three bends to two bends. It no longer needs to be connected to the low-voltage upper clamp 704, and its height is reduced from above to below the low-voltage upper clamp 704. The beginnings of a, b, and c are bolted to the horizontal lead copper busbar 709, and then connected to the terminal block. The end is connected sequentially with the 0-phase copper busbar, and the terminal block is connected directly below the 0-phase bushing 50. All end connections are bolted.

[0065] Compared with conventional distribution transformers of the same capacity, this invention significantly reduces the height without changing the length and width of the transformer, making the transformer smaller and suitable for some scenarios where height is a requirement.

[0066] Furthermore, manufacturing costs are reduced by incorporating the switch into the lower clamp, minimizing transformer size, and reducing the use of steel, transformer oil, and copper. This effectively saves materials while maintaining product performance. The rational coordination and arrangement between the coils, core, and leads ensures convenience during transformer manufacturing and makes the transformer more compact and practical.

[0067] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein, and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A distribution transformer based on a remote-controlled switch, characterized in that, include: The oil tank, a three-phase coil disposed inside the oil tank, a tap changer disposed below the three-phase coil, an adjustment knob disposed on the oil tank, a sleeve disposed above the oil tank, and a fixing assembly disposed inside the oil tank; The three-phase coil includes an A-phase coil, a B-phase coil, and a C-phase coil, and the A-phase coil, the B-phase coil, and the C-phase coil have the same structure. The output terminal of the A-phase coil is provided with several tap leads, which are electrically connected to the tap switch below the A-phase coil; the tap switch is electrically connected to the adjustment knob via a connecting wire.

2. A power distribution transformer based on remote controlled switches according to claim 1, characterized in that: The fixing assembly includes a high-pressure clamp and a fixing plate; The high-pressure clamp is made of channel steel. The fixing plate is fixed to the high-pressure clamp. The fixing plate has a through hole and a nut is welded at the through hole. The nut is located on the side of the fixing plate close to the channel steel. The tap changer is fixedly connected to the fixing plate by bolts.

3. A power distribution transformer based on remote controlled switches as claimed in claim 1, wherein: The fixing assembly further includes a high-voltage upper clamp, a low-voltage upper clamp, and a steel tension strap. The high-voltage upper clamp is disposed on the high-voltage side of the three-phase coil, and the low-voltage upper clamp is disposed on the low-voltage side of the three-phase coil. One end of the steel tension strap is fixedly connected to the high-voltage upper clamp, and the other end is fixedly connected to the low-voltage upper clamp. The high-voltage upper clamp and the low-voltage upper clamp are arranged parallel to each other, and the steel tension strap is arranged perpendicular to both the high-voltage upper clamp and the low-voltage upper clamp.

4. A distribution transformer based on a remote-controlled switch according to claim 3, characterized in that: An insulation strip is provided between the steel pull strip and the yoke of the transformer, and the width of the insulation strip is greater than the width of the pull strip.

5. A distribution transformer based on a remote-controlled switch according to claim 3, characterized in that: The steel tension strip includes a first connecting section, a first ramp section, a horizontal section, a second ramp section, and a second connecting section. The steel tension strip is axially symmetrical along the central axis of the horizontal section, and the included angle between the first connecting section and the first ramp section is 132° to 138°.

6. A distribution transformer based on a remote-controlled switch according to claim 1, characterized in that: The fixing assembly also includes a horizontal lead copper busbar and a low-voltage coil copper busbar. The low-voltage coil copper busbar of the A-phase coil is electrically connected to the A-phase coil, the low-voltage coil copper busbar is electrically connected to the horizontal lead copper busbar, and the horizontal lead copper busbar is electrically connected to the bushing.

7. A distribution transformer based on a remote-controlled switch according to claim 6, characterized in that: The low-voltage coil copper busbar includes a first section, a second section perpendicular to the first section, and a third section perpendicular to the second section. The first section and the third section are located on both sides of the second section, and the third section is located inside the A-phase coil.

8. A distribution transformer based on a remote-controlled switch according to claim 1, characterized in that: The fixing assembly includes a high-pressure upper clamp, a low-pressure upper clamp, a high-pressure lower clamp, and a low-pressure lower clamp. The high-pressure upper clamp and the high-pressure lower clamp are fixedly connected by a pull screw, and the low-pressure upper clamp and the low-pressure lower clamp are fixedly connected by a pull screw.

9. A distribution transformer based on a remote-controlled switch according to claim 8, characterized in that: Two side screws are also fixedly installed between the high-pressure upper clamp and the low-pressure upper clamp.

10. A distribution transformer based on a remote-controlled switch according to claim 1, characterized in that: The tap lead of the A-phase coil includes seven leads, namely X6, X4, X2, X3, X5, X7 and X. The A-phase coil includes 15 layers of coil wound sequentially from the inside out. The first to the 14th layers are connected end to end, and the 15th layer is not connected to the other layers. Leads X6, X4 and X2 are located on the 14th layer, and leads X3, X5, X7 and X are located on the 15th layer.

11. A distribution transformer based on a remote-controlled switch according to claim 10, characterized in that: The coil between the outlet X4 and X2 is a tap section, the coil between the outlet X3 and X5 is a tap section, and the remaining coils are normal sections; the cross-sectional area of ​​the conductor in the tap section is smaller than the cross-sectional area of ​​the conductor in the normal section.

12. A distribution transformer based on a remote-controlled switch according to claim 10, characterized in that: In the A-phase coil, the first and second layers each have 62 turns of coil, the third layer has 63 turns of coil, the fourth to thirteenth layers each have 64 turns of coil, the fourteenth layer has 66 turns of coil, and the fifteenth layer has 61 turns of coil.

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