Layered single coil winding method with multiple taps, layered single coil and transformer

Abstract

The invention provides a multi-tap layer type single coil winding method, a layer type single coil and a transformer, and relates to the technical field of transformer manufacturing, the layer type single coil is wound through a single wire, the wire winding directions of the first n-1 layers of coils are the same, the (n-1) th layer takes a plurality of winding turns as tapping points, taps are led out, and the original wire continues to be wound, a plurality of taps are led out, when the nth layer of coil is wound, a single wire is disconnected and wound in the opposite winding direction so as to ensure that the directions of magnetic fluxes generated by currents of the first (n-1) th layers of wires and the nth layer of wire are consistent, the taps are led out by taking a plurality of winding turns as tapping points, the original wire is continuously wound until the original wire is wound to the other end part of the winding appliance, and finally one tap is led out, no insulation distance exists between the tap X2 and the tap X3 in the coil, and only the insulation distance exists outside the coil, so that the insulation distance is naturally increased, the size of the coil and the weight of the iron core are reduced, the noise and the loss of the transformer are reduced, and the winding process is simple.

Description

Technical Field

[0001] The present invention relates to the technical field of transformer manufacturing, and more specifically, to a method for winding a multi-tapped layer type single coil, a layer type single coil, and a transformer. Background Art

[0002] Layer type coils are widely used in distribution transformers with a capacity of less than 630 kVA. Their compact cylindrical structure and high filling factor can optimize the utilization rate of the iron core window, effectively reduce no-load losses and improve heat dissipation efficiency. Moreover, compared with traditional pancake coils, layer type coils do not require complex transposition and welding processes, thus improving the winding efficiency. Electrically, layer type coils can achieve voltage regulation functions by leading out multiple taps, adjusting the number of turns of the winding to optimize the voltage output, so as to adapt to power grid fluctuations, load changes, and improve equipment performance.

[0003] Currently, on the high-voltage side of transformers with a voltage level of 35 kV and above, to prevent insulation aging or partial discharge, sectional layer type coils are generally used for winding the windings. The coil is divided into several independent sections (such as upper and lower sections), the winding directions of each section are opposite or a transposition process is adopted, and an insulating layer or oil duct is used to isolate between the sections, which can balance the ampere-turn distribution, reduce the short-circuit electrodynamic force generated by the leakage magnetic field, and avoid axial deformation or inter-turn short circuit of the coil. In the sectional layer type transformers disclosed in the prior art, the high-voltage coil is divided into upper and lower parts, and the taps are respectively located at the ends of the two sections and are connected through an external voltage regulating switch, effectively reducing the working voltage between layers. However, in such a sectional layer type coil, if taps are respectively led out from the upper half and the lower half of the high-voltage coil, since it is sectional winding, there are break points between adjacent taps, and the break points are inside the coil. The break points prevent the ampere-turns (current × number of turns) in different tap areas from canceling each other out, and the un-canceled magnetomotive force will intensify the leakage magnetic flux and reduce the short-circuit resistance.

[0004] When winding the winding coils of distribution transformers with a voltage level of 10 kV and below, because the current is large but the voltage is low and no complex tap structure is required, layer type single coils are generally used, which can be continuously wound without transposition or segmentation, and have a high degree of automation. Currently on the market, the layer type single coils of transformers are wound in a continuous manner, and the winding directions of all layers are the same, such as Figure 1The existing layer-type single-coil structure shown is composed of 1 wire wound for 11 layers to form a single coil with a total of 11 layers. In all layers, the wire winding direction is the same. Taking phase A of the three-phase winding as an example, starting from the winding starting point, between the first 10 layers, insulating materials (such as insulating paper, the numbers represent the layers of insulating paper) or oil ducts (such as between the 6th and 7th layers, and between the 8th and 9th layers) are used to separate them. A tap X6 is led out from the 10th layer, and a total of 5 taps, namely X2, X3, X4, X5, and X7, are led out from the 11th layer. Five coil tapping positions are formed between the taps. Among them, connecting tap X2 and tap X3 obtains tapping position 1 of the coil; connecting tap X3 and tap X4 obtains tapping position 2 of the coil; connecting tap X4 and tap X5 obtains tapping position 3 of the coil; connecting tap X5 and tap X6 obtains tapping position 4 of the coil; connecting tap X6 and tap X7 obtains tapping position 5 of the coil. The 10th and 11th layers of the coil are connected together. When transitioning from the 10th layer to the 11th layer, the coil needs to ascend a layer, and a scissor opening will be formed by the wire wound at the ascending layer position. The wire at the scissor opening position needs to be wrapped with insulation. If the insulation process is not well handled, or there is a sudden short circuit outside the transformer, when the coil bears a large mechanical stress, it is easy to cause insulation damage at the scissor opening, leading to coil short circuit, and thus causing the transformer to burn out and power off. As Figure 2 shown, there is a floating voltage between tap X2 and tap X3 of the coil. Therefore, inside the coil, sufficient electrical distance must be left between tap X2 and tap X3. If the wire here deflects during the operation of the transformer but the insulation distance is insufficient, insulation breakdown is likely to occur, which will also cause the transformer to burn out and power off. At the same time, due to the existence of the insulation distance here, the coil size increases, increasing the length and weight of the wire and increasing the resistance loss of the coil. See Figure 1 , when at tapping position 5 of the coil, at this time tap X6 is connected to tap X7, and all the wire turns of the last layer, the 11th layer of the coil, are disengaged. When a sudden short circuit occurs outside the transformer, the mechanical force of the coil increases, and the coil's ability to withstand sudden short circuits is poor. Summary of the Invention

[0005] To solve the problems that in the existing layer-type single coil with multiple taps during winding, the electrical distance requirements between taps are high, the insulation distance is large, resulting in a large coil size, and to solve the problem that the transformer using the existing layer-type single coil with multiple taps has poor short-circuit withstand ability, the present invention proposes a winding method for a layer-type single coil with multiple taps, a layer-type single coil, and a transformer. The winding process is simple, safe and reliable. Sufficient insulation distance is naturally formed between taps in the formed layer-type single coil, reducing the coil size and improving the performance of the transformer.

[0006] To achieve the above technical effects, the technical solution of the present invention is as follows: In a first aspect, the present application proposes a method for winding a multi-tap laminated single coil, including the following steps: S1: Assume that the total number of layers of the laminated single coil to be wound is n, and the layer sequence number of the wound single coil is i. Both i and n are positive integers. Let i = 1. S2: Use any end of a single wire as the coil starting end, and use it as the winding starting point. Start from one end of the winding tool, and wind successively in the winding groove of the winding tool until reaching the other end of the winding tool. S3: Ascend from the i-th layer to the (i + 1)-th layer of the wound coil. Start from one end of the winding tool, and use the same winding direction as the i-th layer to wind successively in the winding groove of the winding tool until reaching the other end of the winding tool, completing the winding of the (i + 1)-th layer of the coil. S4: Determine whether i is less than n - 2. If so, increase the value of i by 1, and return to execute step S3. Otherwise, ascend from the (n - 2)-th layer to the (n - 1)-th layer of the wound coil, and execute S5. S5: Start winding the (n - 1)-th layer: Start from one end of the winding tool, and use the same winding direction as the (n - 2)-th layer to wind successively in the winding groove of the winding tool. Take several winding turns as tapping points to lead out taps. The original wire continues to wind, and then take several winding turns as tapping points to lead out another tap. A total of several taps are led out until reaching the other end of the winding tool. Finally, lead out one tap. After winding is completed, cut off the end of the last led-out tap. S6: Use one end of the remaining single wire after cutting as a tap. After reserving the tap length, the remaining single wire starts from one end of the winding tool and winds successively in the winding groove of the winding tool using the winding direction opposite to the previous n - 1 layers. S7: Take several winding turns as tapping points to lead out taps. The original wire continues to wind, and then take several winding turns as tapping points to lead out another tap. A total of several taps are led out until reaching the other end of the winding tool. Finally, lead out one tap as the coil end.

[0007] Preferably, in step S2, any end of the single wire used as the winding starting point is any one of coil starting ends A, B, or C. In S7, the last led-out tap is any one of coil ends X, Y, or Z. Among them, if the coil starting end is A, the coil end is X; if the coil starting end is B, the coil end is Y; if the coil starting end is C, the coil end is Z.

[0008] Preferably, the wire starts from one end of the winding tool and winds successively in the winding groove of the winding tool until reaching the other end of the winding tool, forming one layer of the wound coil.

[0009] Preferably, the layer-up process is that after the winding of the i-th layer is completed and before the winding of the (i + 1)-th layer starts, the wire that ends the winding of the i-th layer directly makes a sequential transition to the (i + 1)-th layer at the end of the winding device where it is currently located, without changing the position of the end of the winding device, and i is less than n - 2.

[0010] In a second aspect, the present application also proposes a multi-tapped layer type single coil, which is wound by using the above-mentioned multi-tapped layer type single coil winding method. The number of layers of the layer type single coil is n. One end of a single wire is used as the starting point of winding for the first layer. Starting from one end of the winding device, it is sequentially wound in the winding groove of the winding device until the other end of the winding device is reached; When winding the first n - 2 layers of the layer type single coil, after the winding of the i-th layer is completed, the layer is raised from the i-th layer of the wound coil to the (i + 1)-th layer. Starting from one end of the winding device, using the same winding direction as the i-th layer, it is sequentially wound in the winding groove of the winding device until the other end of the winding device is reached, completing the winding of the (i + 1)-th layer of the coil, where i is greater than 1 and less than n - 2; When winding the (n - 1)-th layer of the layer type single coil, starting from one end of the winding device, using the same winding direction as the (n - 2)-th layer, it is sequentially wound in the winding groove of the winding device, and taking several winding turns as tapping points, taps are led out. The original wire continues to be wound, and then taking several winding turns as tapping points, another tap is led out. A total of several taps are led out until the other end of the winding device is reached, and finally a tap is led out. The end of the finally led out tap is cut off; When winding the n-th layer of the layer type single coil, one end of the remaining single wire after cutting is used as a tap. After reserving the tap length, the remaining single wire starts from one end of the winding device and is sequentially wound in the winding groove of the winding device using the winding direction opposite to the first n - 1 layers, and taking several winding turns as tapping points, taps are led out. The original wire continues to be wound, and then taking several winding turns as tapping points, another tap is led out. A total of several taps are led out until the other end of the winding device is reached, and finally a tap is led out as the end of the coil.

[0011] Preferably, according to the interlayer working voltage, interlayer insulation is provided between the i-th layer and the (i + 1)-th layer of the layer type single coil.

[0012] Preferably, several taps led out from the (n - 1)-th layer are located outside the (n - 1)-th layer and are radially led out. Several taps led out from the n-th layer are located outside the n-th layer and are radially led out.

[0013] Preferably, according to the leading-out order during the winding process, the several taps led out from the (n - 1)-th layer are tap X6, tap X4, and tap X2 in sequence, the several taps led out from the n-th layer are tap X3, tap X5, and tap X7 in sequence, and finally a tap is led out as the coil end X; the layer-type single coil forms 5 coil tapping positions by the taps, including: tap X2 - tap X3, tap X3 - tap X4, tap X4 - tap X5, tap X5 - tap X6, tap X6 - tap X7. Among them, tap X2 is at the upper end of the layer-type coil, tap X3 is at the lower end of the layer-type coil, and tap X6 - tap X7 is the minimum tapping position of the coil.

[0014] In a third aspect, the present application proposes a transformer. The winding of the transformer is a layer-type single coil formed by winding a single wire, with multiple taps. The single wire is wound into a layer-type single coil by using the layer-type single coil winding method with multiple taps.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention proposes a layer-type single coil winding method with multiple taps, a layer-type single coil, and a transformer. By winding a layer-type single coil with a single wire, the winding directions of the wires of the first (n - 1) layers of the coil are the same. The (n - 1)-th layer uses several winding turns as tapping points to lead out taps, and the original wire continues to wind. Then, several winding turns are used as tapping points to lead out another tap, and several taps are led out in total until the other end of the winding tool is wound. When winding the n-th layer of the coil, the single wire is disconnected, and the n-th layer of the coil is wound in the opposite winding direction to ensure that the magnetic flux directions generated by the currents of the wires of the first (n - 1) layers and the n-th layer are the same. Several winding turns are used as tapping points to lead out taps, and the original wire continues to wind. Then, several winding turns are used as tapping points to lead out another tap, and several taps are led out in total until the other end of the winding tool is wound. Finally, a tap is led out, so that there is no insulation distance between the coil taps inside the coil, and there is only insulation distance outside the coil. The insulation distance naturally increases, reducing the coil size. The winding process is simple, safe, and reliable, solving the problem that the existing transformer with a layer-type single coil with multiple taps has poor short-circuit withstand ability, and improving the performance of the transformer. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic diagram showing the existing layer-type single coil proposed in the background art of the present invention; Figure 2 A schematic circuit diagram showing the layer-type single coil unfolded in the background art of the present invention; Figure 3 A schematic flow diagram showing the layer-type single coil winding method with multiple taps proposed in Embodiment 1 of the present invention; Figure 4Schematic diagram of the layer-type single coil wound by using the layer-type single coil winding method with multiple taps proposed in Embodiment 1 of the present invention; Figure 5 Schematic circuit diagram after the layer-type single coil wound by using the layer-type single coil winding method with multiple taps proposed in Embodiment 1 of the present invention is unfolded. Detailed implementation manners

[0017] The accompanying drawings are only for illustrative purposes and should not be construed as a limitation to this application; For better illustration of this embodiment, some parts of the accompanying drawings are omitted, enlarged or reduced, which do not represent the actual size; For those skilled in the art, it is understandable that some well-known content descriptions in the accompanying drawings may be omitted.

[0018] The technical solutions of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0019] The description of the positional relationship in the accompanying drawings is only for illustrative purposes and should not be construed as a limitation to this application; Embodiment 1 As Figure 3 shown, this embodiment proposes a layer-type single coil winding method with multiple taps, including the following steps: S1: Assume that the total number of layers of the layer-type single coil to be wound is n, the layer sequence number of the wound single coil is i, both i and n are positive integers, and let i = 1; S2: Take any end of a single wire as the coil head end and use it as the winding starting point. Start from one end of the winding device and wind successively in the winding groove of the winding device until reaching the other end of the winding device; S3: Ascend from the i-th layer to the (i + 1)-th layer of the wound coil. Start from one end of the winding device and use the same winding direction as the i-th layer to wind successively in the winding groove of the winding device until reaching the other end of the winding device to complete the winding of the (i + 1)-th layer of the coil; S4: Judge whether i is less than n - 2. If so, increase the value of i by 1, return to execute step S3. Otherwise, ascend from the (n - 2)-th layer to the (n - 1)-th layer of the wound coil and execute S5; S5: Start winding the (n - 1)-th layer: Start from one end of the winding device and use the same winding direction as the (n - 2)-th layer to wind successively in the winding groove of the winding device. Take several winding turns as tap points to lead out taps. The original wire continues to wind, and then take several winding turns as tap points to lead out another tap. A total of several taps are led out until reaching the other end of the winding device. Finally, lead out one tap, complete the winding, and cut off the end of the last led-out tap; S6: Take one end of the remaining single wire after cutting as a tap. After reserving the tap length, start from one end of the winding device with the remaining single wire, and wind it successively in the winding grooves of the winding device in a winding direction opposite to that of the previous n - 1 layers. S7: Take several winding turns as tapping points to lead out taps. The original wire continues to wind, and then take several winding turns as tapping points to lead out another tap. A total of several taps are led out until winding reaches the other end of the winding device, and finally lead out one tap as the end of the coil.

[0020] In this embodiment, one end of the winding device can be the upper end or the lower end of the winding device. In step S2, any one end of the single wire as the starting point of winding is any one of the coil heads A, B, or C of the coil. In S7, the last tap led out is any one of the coil ends X, Y, or Z. Among them, if the coil head is A, the coil end is X; if the coil head is B, the coil end is Y; if the coil head is C, the coil end is Z. As Figure 4 shown, one end of the single wire as the starting point of winding is the coil head A of the three - phase winding. The coil wound in this embodiment has 11 layers. Refer to Figure 4 , the wire starts from one end of the winding device and winds successively from top to bottom along the winding grooves of the winding device until it reaches the other end of the winding device, forming one layer of the wound coil.

[0021] In this embodiment, the layer - rising is that after the i - th layer winding is completed and before the (i + 1) - th layer winding starts, the wire at the end of the i - th layer winding directly transitions to the (i + 1) - th layer in sequence at the end of the winding device where it is currently located without changing the position of the end of the winding device. i is less than n - 2, that is, in the first 10 layers, the layer - rising is by sequential transition. In specific implementation, after the i - th layer winding is completed, place insulating paper between layers without cutting the wire. Adopt a spiral - rising sequence. When the wire winds from the last turn of the i - th layer to the edge of the other end, guide the wire to the starting position of the (i + 1) - th layer while keeping the winding direction consistent.

[0022] Combined with Figure 4 , when winding the first 10 - layer coil, first take any one end of the single wire as the coil head and use it as the starting point of winding. Start from one end of the winding device (refer to Figure 4 , which is the upper end of the winding device and the coil head is A), and wind successively in the winding grooves of the winding device until it reaches the other end of the winding device (which is the lower end of the winding device). Rise from the first layer to the second layer of the wound coil. Start from the lower end of the winding device and wind successively in the winding grooves of the winding device in the same winding direction as the first layer until it reaches the upper end of the winding device to complete the second - layer winding of the coil. The other layers are similar and will not be elaborated.

[0023] At the start of winding the 10th layer of the coil, using a number of winding turns as tapping points, tap wires are led out. For example, Figure 4 as shown, first tap wire X6 is led out, the original wire continues to be wound, then using a number of winding turns as tapping points, another tap wire X4 is led out. A number of tap wires are led out in total until winding reaches the other end of the winding device. Finally, a tap wire X2 is led out. After winding is completed, the end of the last led-out tap wire is cut off.

[0024] Refer to Figure 4 , taking one end of the remaining single wire after cutting as a tap wire X3. After reserving the tap wire length, the remaining single wire starts from one end of the winding device (refer to Figure 4 , starting from the lower end of the winding device), and using a winding direction opposite to that of the first 10 layers, it is successively wound in the winding groove of the winding device; using a number of winding turns as tapping points, tap wire X5 is led out, the original wire continues to be wound, then using a number of winding turns as tapping points, another tap wire X7 is led out. A number of tap wires are led out in total until winding reaches the other end of the winding device. Finally, a tap wire X is led out, and this tap wire is the end of the coil.

[0025] Embodiment 2 This embodiment proposes a multi-tapped layer type single coil. The layer type single coil is wound by using the multi-tapped layer type single coil winding method. The number of layers of the layer type single coil is n. One arbitrary end of a single wire is used as the winding starting point for the first layer. Starting from one end of the winding device, it is successively wound in the winding groove of the winding device until winding reaches the other end of the winding device; When winding the first n - 2 layers of the layer type single coil, after the i-th layer winding is completed, the coil ascends from the i-th layer to the i + 1-th layer. Starting from one end of the winding device, using the same winding direction as the i-th layer, it is successively wound in the winding groove of the winding device until winding reaches the other end of the winding device, completing the winding of the i + 1-th layer of the coil, where i is greater than 1 and less than n - 2; When winding the (n - 1)-th layer of the layer type single coil, starting from one end of the winding device, using the same winding direction as the (n - 2)-th layer, it is successively wound in the winding groove of the winding device, and using a number of winding turns as tapping points, tap wires are led out. The original wire continues to be wound, then using a number of winding turns as tapping points, another tap wire is led out. A number of tap wires are led out in total until winding reaches the other end of the winding device. Finally, a tap wire is led out. After winding is completed, the end of the last led-out tap wire is cut off; When winding the nth layer of the layer-type single coil, one end of the remaining single wire after cutting is used as a tap. After reserving the tap length, the remaining single wire starts from one end of the winding device and is wound successively in the winding groove of the winding device in the winding direction opposite to the previous n - 1 layers. With several winding turns as the tapping points, taps are led out, and the original wire continues to be wound. Then, with several winding turns as the tapping points, another tap is led out, and several taps are led out in total until the other end of the winding device is reached. Finally, a tap is led out as the coil end.

[0026] In this embodiment, interlayer insulation is provided between the ith layer and the (i + 1)th layer of the layer-type single coil according to the interlayer working voltage.

[0027] See Figure 4 In the shown coil schematic diagram, the voltage difference between different winding layers is not evenly distributed along the axis. Considering the interlayer working voltage, different interlayer insulations need to be set. In the figure, "1" to "11" represent the layers of the layer-type coil. Starting from the A-phase end, 14 layers of insulating paper are used for insulation isolation between the first layer and the upper half end of the second layer of the coil, and 8 layers of insulating paper are used for insulation isolation between the lower half ends. And 13 layers of insulating paper are used for insulation isolation between the lower half ends of the second layer and the third layer, and 7 layers of insulating paper are used for insulation isolation between the upper half ends of the second layer and the third layer. An oil duct is used for insulation isolation between the third layer and the fourth layer, 6 layers of insulating paper are used for insulation isolation between the upper ends of the fourth layer and the fifth layer, and 12 layers of insulating paper are used for insulation isolation between the lower ends of the fourth layer and the fifth layer. The arrangement between the remaining layers is similar, and reference can be made to Figure 4 .

[0028] In this embodiment, the number of turns of different layers of the layer-type single coil is different. In this embodiment, the first 9 layers of the coil have 46 turns, the 10th layer of the coil has 45 turns, and the 11th layer of the coil has 44 turns.

[0029] In this embodiment, the 10th layer and the 11th layer of the coil are wound separately after the same wire is disconnected, that is, the 10th layer and the 11th layer are disconnected. After the 10th layer is wound, when starting to wind the 11th layer, no layer-lifting treatment is required between the layers of the coil. The winding method has a simple process, high production efficiency, and is safe. It avoids the problem in the existing technology that a scissor mouth will be formed at the layer-lifting position of the wire, and the wire at the scissor mouth position needs to be wrapped with insulation treatment. If the process treatment is not good here, or an external sudden short circuit occurs in the transformer, the coil will bear a large mechanical stress, easily causing insulation damage at the scissor mouth and leading to coil short circuit, thus causing the transformer coil to burn out and power outage.

[0030] In this embodiment, several taps led out from the (n - 1)th layer are located outside the (n - 1)th layer and are radially led out. See Figure 4, that is, the taps X2, X4, and X6 led out from the 10th layer are all led out from the outside of the 10th layer, which is radially led out. The taps are not located inside the coil. The several taps led out from the nth layer are located on the outside of the nth layer and are also radially led out. That is, the taps X7, X5, and X3 led out from the 11th layer are all radially led out.

[0031] According to the leading-out order during the winding process, the several taps led out from the 10th layer are tap X6, tap X4, and tap X2 in sequence. The several taps led out from the 11th layer are tap X3, tap X5, and tap X7 in sequence. Finally, a tap is led out as the coil end X. The layer-type single coil forms 5 coil tapping positions by taps, including: tap X2 - tap X3, tap X3 - tap X4, tap X4 - tap X5, tap X5 - tap X6, tap X6 - tap X7. Among them, tap X2 is at the upper end of the layer-type coil, tap X3 is at the lower end of the layer-type coil, and tap X6 - tap X7 is the smallest tapping position of the coil. In this embodiment, see Figure 5 , there is a floating voltage between coil taps X2 and X3. Therefore, there must be enough electrical distance between taps X2 and X3 inside the coil. In the layer-type single coil proposed in this embodiment, tap X2 is at the upper end of the coil, tap X3 is at the lower end of the coil. The insulation distance between tap X2 and tap X3 is large, and its size is equal to the height size of the coil. And there is no insulation distance between tap X2 and tap X3 inside the coil, only an insulation distance exists outside. This insulation distance is very large. So when the coil is operating, the wire insulation at taps X2 and X3 inside the coil will not be broken down, and it will not cause the transformer coil to burn out and power off. At the same time, since there is no insulation distance between tap X2 and tap X3 inside the coil, the occupancy efficiency of the wire is improved, the overall size of the coil can be reduced, the length and weight of the wire can be reduced, and the resistance loss of the coil can be reduced. Moreover, since the insulation between tap X2 and tap X3 is not inside the coil but outside the coil, the height size of the coil can be effectively reduced. Since the coil is sleeved on the iron core, the size of the iron core is also reduced accordingly, achieving the purpose of reducing the weight of the iron core, reducing the loss and noise of the iron core See Figure 5 , when the coil is at the smallest tapping position of tap X6 - tap X7, at this time tap X6 - tap X7 are connected, there are still 20 turns in the last layer of the coil, and the 20 - turn coil is close to the fixed end of the coil. The ampere - turns between the high - voltage and low - voltage windings are relatively balanced. When an external sudden short - circuit occurs in the transformer, the sudden mechanical force borne by the coil can be reduced, and the coil has a strong ability to withstand the sudden short - circuit force.

[0032] Embodiment 3 This embodiment provides a transformer. The winding of the transformer is a layer-type single coil formed by winding a single wire, with multiple taps. The single wire is wound into a layer-type single coil by using the layer-type single coil winding method with multiple taps.

[0033] Obviously, the above embodiments of the present invention are only examples for clearly explaining the present invention, rather than limitations on the implementation manners of the present invention. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to enumerate all implementation manners here. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. A method for winding a multi-tapped layer type single coil, characterized in that, It includes the following steps: S1: Let the total number of layers of the to-be-wound layer type single coil be n, the layer sequence number of the wound single coil be i, both i and n are positive integers, n is the outermost layer of the layer type single coil, and let i = 1; S2: Take any end of a single wire as the coil starting end, and use it as the winding starting point. Start from one end of the winding device, and wind successively in the winding groove of the winding device until reaching the other end of the winding device; S3: Ascend from the i-th layer of the wound coil to the (i + 1)-th layer. Start from one end of the winding device, adopt the same winding direction as the i-th layer, and wind successively in the winding groove of the winding device until reaching the other end of the winding device to complete the winding of the (i + 1)-th layer of the coil; S4: Judge whether i is less than n - 2. If so, increase the value of i by 1, and return to execute step S3. Otherwise, ascend from the (n - 2)-th layer of the wound coil to the (n - 1)-th layer, and execute S5; S5: Start the winding of the (n - 1)-th layer: Start from one end of the winding device, adopt the same winding direction as the (n - 2)-th layer, and wind successively in the winding groove of the winding device. Use several winding turns as tapping points to lead out taps, continue to wind the original wire, then use several winding turns as tapping points to lead out another tap, and lead out several taps in total until reaching the other end of the winding device. Finally, lead out a tap, complete the winding, and cut off the end of the finally led-out tap; S6: Take one end of the remaining single wire after cutting as a tap. After reserving the tap length, the remaining single wire starts from one end of the winding device and winds successively in the winding groove of the winding device in the winding direction opposite to the previous (n - 1) layers; S7: Use several winding turns as tapping points to lead out taps, continue to wind the original wire, then use several winding turns as tapping points to lead out another tap, and lead out several taps in total until reaching the other end of the winding device. Finally, lead out a tap as the coil end.

2. The method for winding a multi-tapped layer type single coil according to claim 1, characterized in that, In step S2, any end of the single wire used as the winding starting point is any one of the coil starting ends A, B, or C. In S7, the finally led-out tap is any one of the coil ends X, Y, or Z. Among them, if the coil starting end is A, the coil end is X; if the coil starting end is B, the coil end is Y; if the coil starting end is C, the coil end is Z.

3. The method for winding a multi-tapped layer type single coil according to claim 1, characterized in that, The wire starts from one end of the winding device and winds successively in the winding groove of the winding device until reaching the other end of the winding device to form a layer of the wound coil.

4. The method for winding a multi-tapped layer type single coil according to claim 1, characterized in that, The so-called layer ascending means that after the winding of the i-th layer is completed and before the winding of the (i + 1)-th layer starts, the wire at the end of the winding of the i-th layer directly makes a sequential transition to the (i + 1)-th layer at the end of the winding device where it is currently located without performing end transposition of the winding device, and i is less than n - 2.

5. A multi-tapped layer type single coil, characterized in that, The layer type single coil is wound by using the layer type single coil winding method with multiple taps described in any one of claims 1 to 4. The number of layers of the layer type single coil is n. The first layer starts from any end of a single wire as the winding starting point, starts from one end of the winding device, and winds successively in the winding groove of the winding device until reaching the other end of the winding device; When winding the first n - 2 layers of the layer - type single - coil, after the winding of the i - th layer is completed, the layer is raised from the i - th layer to the i + 1 - th layer of the winding coil. Starting from one end of the winding device, using the same winding direction as the i - th layer, it is successively wound in the winding groove of the winding device until the other end of the winding device is reached, and the winding of the i + 1 - th layer of the coil is completed, where i is greater than 1 and less than n - 2; When winding the (n - 1) - th layer of the layer - type single - coil, starting from one end of the winding device, using the same winding direction as the (n - 2) - th layer, it is successively wound in the winding groove of the winding device. Taking several winding turns as tapping points, taps are led out, the original wire continues to be wound, and then taking several winding turns as tapping points, another tap is led out. A total of several taps are led out until the other end of the winding device is reached. Finally, a tap is led out, and the winding is completed. The end of the finally led - out tap is cut off; When winding the n - th layer of the layer - type single - coil, one end of the remaining single - wire after cutting is used as a tap. After reserving the tap length, the remaining single - wire starts from one end of the winding device, using the winding direction opposite to the first n - 1 layers, and is successively wound in the winding groove of the winding device. Taking several winding turns as tapping points, taps are led out, the original wire continues to be wound, and then taking several winding turns as tapping points, another tap is led out. A total of several taps are led out until the other end of the winding device is reached. Finally, a tap is led out as the end of the coil.

6. The multi-tapped layer type single coil according to claim 5, characterized in that, According to the inter - layer working voltage, inter - layer insulation is provided between the i - th layer and the i + 1 - th layer of the layer - type single - coil.

7. The multi-tapped layer type single coil according to claim 6, characterized in that, The several taps led out from the (n - 1) - th layer are located outside the (n - 1) - th layer and are radially led out.

8. The multi-tapped layer type single coil according to claim 7, characterized in that, The several taps led out from the n - th layer are located outside the n - th layer and are radially led out.

9. The multi-tapped layer type single coil according to claim 8, characterized in that, According to the leading - out order during the winding process, the several taps led out from the (n - 1) - th layer are successively tap X6, tap X4, and tap X2, and the several taps led out from the n - th layer are successively tap X3, tap X5, and tap X7. Finally, a tap is led out as the coil end X. The layer - type single - coil forms 5 coil tapping positions by taps, including: tap X2 - tap X3, tap X3 - tap X4, tap X4 - tap X5, tap X5 - tap X6, tap X6 - tap X7. Among them, tap X2 is at the upper end of the layer - type coil, tap X3 is at the lower end of the layer - type coil, and tap X6 - tap X7 is the minimum tapping position of the coil.

10. A transformer, characterized in that, The winding of the transformer is a layer - type single - coil formed by winding a single wire with multiple taps. The single wire is wound into a layer - type single - coil by using the layer - type single - coil winding method with multiple taps described in any one of claims 1 to 4.

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