Suspension winding for high-frequency transformer and method for determining number of suspension assemblies

Abstract

The invention discloses a suspension type winding for a high-frequency transformer and a method for determining the number of suspension assemblies, and particularly relates to the technical field of transformers. The invention discloses a suspension type winding for a high-frequency transformer and a method for determining the number of suspension assemblies. The suspension type winding comprises the suspension assemblies, a transformer winding, an upper panel and a lower panel, the suspension assembly is vertically arranged between the upper panel and the lower panel and is used for supporting an outer side winding; the outer winding is located on the periphery of the inner winding through the suspension assembly, and the gap between the inner winding and the outer winding is completely filled with epoxy resin to form an integrated insulating layer. According to the method for determining the number of the suspension type windings and the suspension assemblies for the high-frequency transformer, dielectric constant mutation caused by traditional supporting strips can be eliminated, the interface polarization effect is reduced, and the partial discharge risk is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of transformers, and in particular to a method for determining the number of suspension windings and suspension components used in high-frequency transformers. Background Art

[0002] High-frequency transformers are electromagnetic devices widely used in power systems. In high-frequency transformer design, the transformer's first winding is typically assembled with the core. A second winding is then mounted outside the first. A brace is placed between the two windings to secure the second winding. Epoxy resin is then injected between the first (inner) and second (outer) windings, securing the windings together. During transformer operation, partial discharge (PD) can occur between the inner and outer windings. One cause of this is uneven dielectric distribution between the windings, leading to uneven magnetic field distribution. The presence of a mixture of winding braces and epoxy resin during winding assembly is one possible cause of this dielectric inhomogeneity. Therefore, further research is needed to optimize the transformer's structural design to avoid dielectric inhomogeneity between the windings and reduce the occurrence of partial discharge. Summary of the Invention

[0003] In view of the above situation, in order to overcome the defects of the existing technology, the present invention provides a method for determining the number of suspended windings and suspension components for high-frequency transformers, which can eliminate the dielectric constant mutation caused by traditional struts, reduce the interface polarization effect, and reduce the risk of partial discharge.

[0004] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0005] A suspension winding for a high-frequency transformer is characterized in that it includes: a suspension component, a transformer winding, an upper panel and a lower panel; the suspension component is vertically installed between the upper panel and the lower panel to support the outer winding; the outer winding is located outside the inner winding through the suspension component, and the gap between the inner and outer windings is completely filled with epoxy resin to form an integrated insulation layer.

[0006] Preferably, an insert block is provided at the top of the suspension component, the upper panel is provided with a socket adapted to the insert block, and the lower panel is provided with a fixing hole, which is screwed through the fixing hole and threadedly connected to the bottom of the suspension component to fix the suspension component.

[0007] Preferably, the suspension component is a high-strength insulating plate, and a plurality of semicircular grooves are provided on the side thereof in contact with the outer winding, and support plates are fixed at the edges of the upper and lower openings of the semicircular grooves.

[0008] Preferably, the support plate is arranged at an angle.

[0009] Preferably, an arc-shaped groove and a protrusion are respectively provided on the upper and lower parts of the support plate to limit the winding displacement of the outer winding.

[0010] Preferably, the two ends are in a bow-shaped structure to increase the creepage distance.

[0011] The method for determining the number of suspension components includes the following steps:

[0012] (a) Calculate the minimum number of suspension components based on the mass m of the suspension winding and the load F of a single suspension component.

[0013] n1=mg / F h ;

[0014] (b) Based on the suspension winding area A w and shape factor k a , calculate the number of suspension components n2 = k a A w ; A w The following formula can be used for calculation:

[0015] A w =L w b w k w / c w

[0016] Where, L w 、b w 、k w 、c w They are the length, width, correction factor, and number of layers of the suspension winding; the width can be determined by the transformer winding design:

[0017] b w ∈[b wmin b wmax ];

[0018] (c) Number of suspension components n h The constraints that need to be met are:

[0019]

[0020] Reliable heat dissipation area of ​​the suspension winding surface A Q for:

[0021] A Q =A w -A h ;

[0022] Where A h is the area of ​​the suspension component, which can be determined by the following formula:

[0023] A h =ah b h n h ;

[0024] Where a h 、b h 、n h are the length, width, and number of suspension components respectively;

[0025] The temperature rise ΔT of the winding is:

[0026]

[0027] Where Q is the heat generated by the suspension winding; k Q is the heat dissipation coefficient;

[0028] Set the temperature rise range of the transformer:

[0029] ΔT∈[0ΔT max ];

[0030] Where, ΔT max is the maximum allowable temperature rise;

[0031] The objective function is obtained as:

[0032] minf(n h )

[0033] The minimum objective function is solved through optimization algorithm.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] (1) The present invention independently supports the outer winding through a suspension assembly, and only a single epoxy resin is filled between the inner and outer windings, eliminating the dielectric constant mutation caused by traditional support bars, reducing the interface polarization effect, and reducing the risk of partial discharge. The epoxy resin infusion path is unobstructed, and there are no air gaps or delamination defects after curing, thereby improving the integrity of the insulation layer;

[0036] (2) The inclined layout of the support plate and the arc-shaped groove and protrusion design reduce the probability of magnetic field distortion caused by winding displacement;

[0037] (3) The suspension assembly adopts a bow-shaped end design, which increases the creepage distance while reducing the edge electric field concentration and improving the voltage resistance level;

[0038] (4) The present invention is based on an optimization model for the number of suspension components. By jointly solving temperature rise constraints and mechanical constraints, it achieves a balance between maximizing the heat dissipation area and minimizing the number of components, thereby ensuring the heat dissipation effect and reducing material costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1A schematic structural diagram of a suspension winding for a high-frequency transformer provided by the present invention;

[0040] Figure 2 A schematic structural diagram of a suspension winding for a high-frequency transformer provided by the present invention;

[0041] Figure 3 for Figure 1 The structural diagram of the suspension component in the suspension winding of the high-frequency transformer is shown;

[0042] Figure 4 for Figure 1 The structural diagram of the suspension component in the suspension winding of the high-frequency transformer is shown;

[0043] Figure 5 for Figure 1 A schematic diagram of a portion of the structure of a suspension component in a suspension winding for a high-frequency transformer is shown;

[0044] Figure 6 for Figure 1 The diagram shows a partial structural diagram of a suspension component in a suspension winding for a high-frequency transformer.

[0045] Among them, the names corresponding to the figure marks are: 1-suspension component, 2-transformer winding, 3-upper panel, 4-lower panel, 5-fixing hole, 6-semicircular groove, 7-fixing plate, 8-arc groove, 9-protrusion, 10-insert block. DETAILED DESCRIPTION

[0046] The present invention will be further described below with reference to the accompanying drawings and examples. The embodiments of the present invention include but are not limited to the following examples.

[0047] In the design and assembly of high-frequency transformers, it is necessary to install the primary winding and the secondary winding of the transformer together to couple the magnetic field to achieve the transfer of electrical energy. In order to distinguish the spatial positions of the two windings, the two windings are referred to as inner windings and outer windings in the present invention. The inner winding refers to the winding that is closely adjacent to the iron core, and the outer winding is outside the inner winding. The outer winding can be designed as a primary winding or a secondary winding, which depends on the specific application of the transformer. The inner winding corresponds to the outer winding. After the inner winding is installed, when the outer winding is installed, the present invention proposes to design the outer winding as a suspended winding.

[0048] like Figure 1-6As shown, the suspension winding for a high-frequency transformer provided by the present invention includes: a suspension component 1, a transformer winding 2 (outer winding), an upper panel 3 and a lower panel 4. The suspension component 1 is vertically installed between the upper panel 3 and the lower panel 4. The suspension component 1 is used to support the transformer winding 2. Epoxy resin is filled between the inner winding of the transformer and the suspension winding to assemble the transformer as a whole. Only epoxy resin is filled between the inner and outer windings without interference from struts. The dielectric constant distribution is continuous, reducing the interface polarization effect. After the epoxy resin is cured, an integrated insulating layer is formed, which reduces the risk of air gaps or delamination compared to traditional struts that easily cause uneven resin flow.

[0049] like Figure 1-3 As shown, an insert block 10 is provided at the top of the suspension component 1, and a plurality of insert holes are provided on the top of the upper panel 3. The insert block 10 is adapted to the insert holes, and a fixing hole 5 is installed at the bottom of the lower panel 4. The screw passes through the fixing hole 5 and is threadedly connected to the bottom of the suspension component 1. Through the cooperation of the insert block 10, the insert hole, the screw and the fixing hole 5, the suspension component 1 can be stably fixed between the upper panel 3 and the lower panel 4.

[0050] like Figure 3-6 As shown, a plurality of semicircular grooves 6 are provided on the side of the suspension component 1 in contact with the transformer winding 2, which are adapted to the winding of the transformer winding 2. Support plates 7 are fixed at the upper and lower edges of the semicircular grooves 6. The fixed plates 7 are in contact with the winding of the transformer winding 2. The plurality of semicircular grooves 6 and the plurality of support plates 7 are used to support the transformer winding 2. After the epoxy resin solidifies, it fixes the transformer winding 2.

[0051] Furthermore, the support plate 7 is tilted to block the winding of the transformer winding 2 so that the winding of the transformer winding 2 is more stably located inside the semicircular groove 6 .

[0052] Furthermore, an arc-shaped groove 8 and a protrusion 9 are respectively provided on the upper and lower parts of the support plate 7. When the winding of the transformer winding 2 is located on the semicircular groove 6 and the support plate 7, the protrusion 9 and the arc-shaped groove 8 are in contact with the winding of the transformer winding 2, and both further make the winding of the transformer winding 2 stably located inside the semicircular groove 6.

[0053] The suspension component 1 is a high-strength insulating board, which may be, but is not limited to, a glass fiber reinforced epoxy board, with both ends having a bow-shaped structure to increase creepage distance.

[0054] Due to the large weight and volume of the transformer, the requirements for the suspension assembly 1 are relatively high. An appropriate number of suspension assemblies is required to maintain the overall stability of the transformer. However, increasing the number of suspension assemblies will affect the heat dissipation and cost of the transformer.

[0055] Meanwhile, in the design of the transformer suspension winding, if the volume of the suspension winding 2 is designed to be too large, the heat dissipation area can be increased and the temperature rise can be reduced, but the number of suspension components 1 will increase.

[0056] Therefore, how to simultaneously consider the transformer's suspension winding design, heat dissipation design, and suspension component quantity design to obtain the optimal result is a problem to be solved in the present invention.

[0057] In the present invention, the temperature rise calculation of the transformer and the bearing capacity of the suspension assembly are combined, the number of suspension assemblies is taken as the optimization target, and the winding temperature rise is taken as the constraint condition to obtain the parameters of the suspension assembly.

[0058] When the mass of the transformer suspension winding is m, the number of suspension components n1 that needs to be designed is:

[0059] n1=mg / F h (1)

[0060] Where mg is gravity; F is the load that a single suspension component can bear;

[0061] At the same time, the number of suspension groups also needs to consider the total area of ​​the winding:

[0062] n2=k a A w (2)

[0063] Where k a is the shape factor, which is determined by the winding process; A w is the area of ​​the suspension winding, which can be calculated using the following formula:

[0064] A w =L w b w k w / c w (3)

[0065] Where, L w 、b w 、k w 、c w They are the length, width, correction factor, and number of layers of the suspension winding; the width can be determined by the transformer winding design:

[0066] b w ∈[b wmin b wmax ](4)

[0067] Therefore, the number of suspension components n h The constraints that need to be met are:

[0068]

[0069] Reliable heat dissipation area of ​​the suspension winding surface A Q for:

[0070] A Q =A w -A h (6)

[0071] Where A h is the area of ​​the suspension component, which can be determined by the following formula:

[0072] A h =a h b h n h (7)

[0073] Where a h 、b h 、n h are the length, width, and number of suspension components respectively;

[0074] The temperature rise ΔT of the winding is then:

[0075]

[0076] Where Q is the heat generated by the suspension winding; k Q is the heat dissipation coefficient;

[0077] The temperature rise range of the transformer can be set:

[0078] ΔT∈[0ΔT max ](9)

[0079] Where, ΔT max is the maximum allowable temperature rise;

[0080] The objective function can be obtained as:

[0081] minf(n h )(10)

[0082] That is, according to the constraints, after calculation using the optimization algorithm, it can be guaranteed that the number of suspension components is minimized within a certain temperature rise range.

[0083] The specific optimization algorithm may be a mathematical optimization algorithm, including but not limited to a genetic algorithm and a particle swarm algorithm. It should be noted that the mathematical optimization algorithm used is a tool for optimizing the objective function in the embodiments of the present invention and is part of the present invention. The algorithm itself is not the innovation of the present invention.

[0084] In the present invention, the outer winding of the transformer is fixed in a hanging manner, and the medium between the outer winding and the inner winding is more uniform, which can effectively reduce the partial discharge of the transformer and improve the performance of the transformer; the hanging design is conducive to the assembly of the transformer winding, improves production efficiency and reduces production costs.

Claims

1. A suspension winding for a high-frequency transformer, characterized in that: include: A suspension assembly (1), a transformer winding (2), an upper panel (3) and a lower panel (4); The suspension assembly (1) is vertically mounted between the upper panel (3) and the lower panel (4) and is used to support the outer winding (2); The outer winding (2) is located outside the inner winding through the suspension component (1), and the gap between the inner and outer windings is completely filled with epoxy resin to form an integrated insulation layer.

2. The suspension winding for a high-frequency transformer according to claim 1, characterized in that: The top of the suspension component (1) is provided with an insert block (10), the upper panel (3) is provided with a socket adapted to the insert block (10), and the lower panel (4) is provided with a fixing hole (5), which is threadedly connected to the bottom of the suspension component (1) by a screw passing through the fixing hole (5) to achieve fixation of the suspension component (1).

3. The suspension winding for a high-frequency transformer according to claim 1, characterized in that: The suspension component (1) is a high-strength insulating plate, and a plurality of semicircular grooves (6) are provided on the side in contact with the outer winding (2). Support plates (7) are fixed at the upper and lower edges of the semicircular grooves (6).

4. The suspension winding for a high-frequency transformer according to claim 3, characterized in that: The support plate (7) is arranged tilted.

5. The suspension winding for a high-frequency transformer according to claim 3, characterized in that: The upper and lower parts of the support plate (7) are respectively provided with an arc-shaped groove (8) and a protrusion (9) for limiting the winding displacement of the outer winding (2).

6. The suspension winding for a high-frequency transformer according to claim 1, characterized in that: The suspension component (1) adopts at least one of a glass fiber reinforced epoxy board, a polyimide board or a ceramic filled epoxy board, and has bow-shaped structures at both ends to increase the creepage distance.

7. A method for determining the number of suspension components, applicable to the suspension winding for a high-frequency transformer according to any one of claims 1 to 6, characterized in that: The method for determining the number of suspension components comprises the following steps: (a) Calculate the minimum number of suspension components based on the mass m of the suspension winding and the load F of a single suspension component. n1=mg / F h ; (b) Based on the suspension winding area A w and shape factor k a , calculate the number of suspension components n2 = k a A w ; A w The following formula can be used for calculation: A w =L w b w k w / c w Where, L w 、b w 、k w 、c w They are the length, width, correction factor, and number of layers of the suspension winding; the width can be determined by the transformer winding design: b w ∈[b wmin b wmax ]; (c) Number of suspension components n h The constraints that need to be met are: Reliable heat dissipation area of ​​the suspension winding surface A Q for: A Q =A w -A h ; Where A h is the area of ​​the suspension component, which can be determined by the following formula: A h =a h b h n h ; Where a h 、b h 、n h are the length, width, and number of suspension components respectively; The temperature rise ΔT of the winding is: Where Q is the heat generated by the suspension winding; k Q is the heat dissipation coefficient; Set the temperature rise range of the transformer: ΔT∈[0 ΔT max ]; Where, ΔT max is the maximum allowable temperature rise; The objective function is obtained as: where f(n h ) The minimum objective function is solved through optimization algorithm.

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