A method and device for calculating distributed capacitance and optimizing common-mode noise of high-frequency transformer

Abstract

The present invention relates to a method and device for calculating the distributed capacitance and optimizing the common-mode noise of a high-frequency transformer, which mainly changes the number of layers of the primary winding. After the number of layers of the primary winding is changed, the height of the primary winding and the potential difference between the primary and secondary windings will change. By using the method of unified variables, an expression for constructing the distributed capacitance between the primary and secondary sides of the high-frequency transformer with respect to the number of layers of the primary winding is derived, thereby obtaining a strategy for suppressing the common-mode noise of the high-frequency transformer. By changing the number of layers of the primary winding, the distributed capacitance between the primary and secondary sides can be reduced without adding other reverse windings and shielding layers, thereby achieving the effect of suppressing the common-mode noise of the high-frequency transformer. The harm of the common-mode noise transmitted by the high-frequency transformer in the power converter system is solved, so that the common-mode noise signals received by the input and output cable ends are greatly weakened, and the electromagnetic radiation interference of the common-mode noise of the power converter system cable is significantly weakened.

Description

Technical Field

[0001] The present invention relates to the field of high-frequency electromagnetic interference resistance, and in particular to a method and device for calculating distributed capacitance and optimizing common-mode noise of a high-frequency transformer. Background Art

[0002] Due to its high operating frequency, high-frequency transformers can indeed reduce the size and weight of transformers, which is of great significance for modern power generation and power electronic equipment. With the increase in the functions of smart meters and the reduction in size, traditional linear power supplies cannot meet the requirements, and high-frequency switching power supplies are gradually used in the power supply part of the meter. Compared with traditional low-frequency linear power supplies, high-frequency switching power supplies have the advantages of wide input voltage, high efficiency (energy saving), fast response speed, and high power density, but they also have disadvantages such as slightly higher failure rate, high-frequency interference, and poor surge resistance. The switching power supply for smart meters is different from the general switching power supply. It has the characteristics of high input and low output, high voltage resistance requirements, uninterrupted power supply, complex working environment, and large temperature difference span. This requires the switching power supply in the smart meter to have high stability and high reliability to meet the needs of the smart meter. The parasitic parameters of the switching power supply transformer are the main reasons affecting the reliability and stability of the power supply. The parasitic parameters of the transformer are mainly leakage inductance and distributed capacitance.

[0003] The switching power supply for smart meters has a high input voltage and the load is lightly loaded for a long time. Therefore, in order to reduce the temperature rise of power devices, the primary inductance of the high-frequency transformer is generally large. The large primary inductance leads to a large number of turns in the primary winding, which is often wound into a multi-layer structure, so that the equivalent distributed capacitance of the primary winding is large. According to the research of researchers, the influence of the transformer distributed capacitance on the high-voltage and high-frequency switching power supply circuit can be summarized as follows: 1. When the winding voltage of the primary winding changes, the energy in the distributed capacitance will also change, which will generate high-frequency oscillation loop current inside the transformer and in the main circuit loop, increasing the loss of the transformer and power devices. 2. The higher the transformer winding voltage, the greater the energy stored in the distributed capacitance. At the moment when the switch tube is turned on, this part of the energy flows instantly in the transformer and the main circuit to generate a large current spike, affecting the reliability of the switch tube. 3. The faster the switch tube is turned on, the faster the winding voltage changes, so the energy flow in the winding distributed capacitance will also be faster to form a large current spike. Although the slower switching speed can reduce the current peak amplitude caused by the distributed capacitance, it will prolong the duration of the peak. Therefore, a larger filter device is required, which causes the current phase shift and is not conducive to the closed-loop control of the entire power supply system. In addition, a large number of electric meter manufacturers currently use the power supply integrated circuit built into the switch tube to design the required power supply. The switching speed of the switch tube cannot be adjusted, so there is no way to reduce the influence of the distributed capacitance by adjusting the switching speed of the switch tube.

[0004] By increasing the operating frequency, high-frequency transformers can reduce the size of the magnetic core, thereby reducing the size and weight of the transformer. This is because at high frequencies, the eddy current loss and hysteresis loss in the core are reduced, allowing the use of thinner insulation materials and smaller coil turns. Since the copper loss and iron loss of high-frequency transformers are significantly reduced, the efficiency of the transformer is improved. High efficiency means energy conservation and environmental protection, which is particularly important in the field of modern power generation. Due to its fast dynamic response characteristics, high-frequency transformers can effectively suppress voltage fluctuations and current shocks, which is crucial to the stable operation of power systems.

[0005] At present, the mechanism of electromagnetic interference of high-frequency transformers has been studied at home and abroad, and the equivalent circuit model of high-frequency transformers has been constructed. There is also some research on the calculation of distributed capacitance. In terms of electromagnetic interference suppression, common methods include shielding method, reverse winding method, and optimized winding structure method. However, there is a lack of systematic research on how to optimize the winding structure. Summary of the invention

[0006] In this context, the purpose of the present invention is to provide a method and device for optimizing the common-mode noise of a high-frequency transformer, which can reduce the distributed capacitance between the primary and secondary sides of the high-frequency transformer, and provide a method for calculating the distributed capacitance, thereby achieving the purpose of suppressing the common-mode noise of the high-frequency transformer.

[0007] The present invention first discloses a method for calculating distributed capacitance of a high-frequency transformer and optimizing common-mode noise, the method comprising:

[0008] Step 1: Obtain the electric field strength between the primary and secondary windings; and equate the energy between the primary and secondary windings to the energy stored in the distributed capacitance between the primary and secondary windings; calculate the distributed capacitance of the multilayer windings from the electric field strength and the energy stored in the distributed capacitance between the windings;

[0009] Step 2: Set the number of turns of the primary winding facing the secondary winding p 1 Ratio to the total number of turns of the primary winding is x; the number of layers of the primary winding is , set the number of primary winding layers to t , then the primary winding height is , H is the height of the primary winding before stratification;

[0010] Step 3: Count the turns of the secondary winding from the primary winding p 1 Substitute the ratio of the total number of turns of the primary winding, the number of layers of the primary winding, and the height of the primary winding into the distributed capacitance of the multilayer winding to obtain the capacitance expression of the primary winding layers with respect to the primary and secondary sides;

[0011] Step 4: Calculate the monotonicity of the primary winding layer number expressed with respect to the primary and secondary side distributed capacitances based on the secondary and primary winding turns ratio, and obtain the corresponding layering strategy based on its monotonicity; when the primary winding layer number is not less than the extreme value point, the more primary winding layer numbers there are, the smaller the distributed capacitance is, and the smaller the common mode noise is.

[0012] Preferably, the specific process of calculating the distributed capacitance of the multilayer winding from the electric field strength and the energy stored in the distributed capacitance between the side windings is:

[0013] 1) First calculate the electric field strength between the primary and secondary windings:

[0014] ;

[0015] 2) According to the energy equivalence principle, the energy between the primary winding and the secondary winding is equivalent to the energy stored in the distributed capacitance between the primary winding and the secondary winding. The formula is:

[0016] ;

[0017] 3) The distributed capacitance between the primary and secondary windings is obtained by combining:

[0018] ;

[0019] U is the potential difference between the primary and secondary sides, d is the distance between the primary and secondary sides, p 1 is the number of turns of the primary winding facing the secondary winding, p is the total number of turns of the primary winding, U 1 is the primary winding voltage, U 2 is the secondary winding voltage, l is the average turn length of the winding, h is the primary winding height, a is the turns ratio of the secondary and primary windings, and ε is the dielectric constant.

[0020] Preferably, the expression of the primary side winding layer number with respect to the primary side and secondary side distributed capacitance is specifically: the primary side winding layer number t , primary winding height , the number of turns of the primary winding facing the secondary winding p 1 Ratio to the total number of turns of the primary winding , substituting into the distributed capacitance formula between the primary and secondary sides:

[0021] .

[0022] Preferably, the turns ratio of the primary and secondary windings of the high-frequency transformer is 10:1. When the number of layers of the primary winding is not less than 1.27, the more layers of the primary winding, the smaller the distributed capacitance and the smaller the common-mode noise.

[0023] Preferably, the turns ratio of the primary and secondary windings of the high-frequency transformer is 2:1. When the number of layers of the primary winding is greater than or equal to 1 and less than or equal to 2, the more layers of the primary winding, the greater the distributed capacitance C, and the greater the common-mode interference.

[0024] Preferably, the turns ratio of the primary and secondary windings of the high-frequency transformer is 2:1. When the number of layers of the primary winding is greater than 2, the more layers of the primary winding, the smaller the distributed capacitance C, and the smaller the common-mode interference.

[0025] The present invention also discloses a device for calculating distributed capacitance of a high-frequency transformer and optimizing common-mode noise, the device comprising:

[0026] A calculation unit is used to obtain the electric field strength between the primary and secondary windings; and the energy between the primary and secondary windings is equivalent to the energy stored in the distributed capacitance between the primary and secondary windings; and the distributed capacitance of the multi-layer winding is calculated from the electric field strength and the energy stored in the distributed capacitance between the windings;

[0027] Conversion unit, set the number of turns of the primary winding facing the secondary winding p 1 Ratio to the total number of turns of the primary winding is x; the number of layers of the primary winding is , set the number of primary winding layers to t , then the primary winding height is , H is the height of the primary winding before stratification;

[0028] The building unit consists of a primary winding facing the secondary winding turns. p 1 Substitute the ratio of the total number of turns of the primary winding, the number of layers of the primary winding, and the height of the primary winding into the distributed capacitance of the multilayer winding to obtain the capacitance expression of the primary winding layers with respect to the primary and secondary sides;

[0029] The strategy analysis unit calculates the monotonicity of the primary winding layer number expressed with respect to the primary and secondary side distributed capacitances according to the secondary and primary winding turns ratio, and obtains the corresponding stratification strategy according to the monotonicity; when the primary winding layer number is not less than the extreme value point, the more primary winding stratification layers there are, the smaller the distributed capacitance is, and the smaller the common mode noise is.

[0030] Preferably, the calculation unit also includes: a field strength acquisition unit, which acquires the electric field strength between the primary and secondary windings; and an energy conversion unit, which, according to the energy equivalence principle, converts the energy between the primary and secondary windings into energy stored in the distributed capacitance between the primary and secondary windings.

[0031] Preferably, the device further comprises:

[0032] at least one processor; and a memory in communication with the at least one processor; wherein,

[0033] The memory stores a computer program executable by at least one processor, and the computer program is executed by at least one processor.

[0034] The present invention proposes a method for optimizing the common-mode noise of a high-frequency transformer. By changing the number of primary-side winding layers, the distributed capacitance between the primary and secondary sides can be reduced without adding other reverse windings and shielding layers, thereby achieving the effect of suppressing the common-mode noise of the high-frequency transformer. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a schematic diagram of the layering of high-frequency transformer windings;

[0036] Figure 2 Flowchart of the common mode noise optimization method for high frequency transformer;

[0037] Figure 3 It is a schematic diagram of the high-frequency transformer winding structure;

[0038] Figure 4 This is a schematic diagram of the winding structure before layering of the high-frequency transformer;

[0039] Figure 5 This is a schematic diagram of the winding structure of the high-frequency transformer after layering. DETAILED DESCRIPTION

[0040] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. Preferred embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thoroughly and comprehensively understood. It should be noted that, unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by technicians in the technical field of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0041] The present invention will be further described below in conjunction with the embodiments.

[0042] like Figure 1 The figure shows the schematic diagram of the high-frequency transformer winding layering, which includes the change from the traditional single-layer primary winding layering on the left to the multi-layer primary winding on the right, providing a circuit structure basis for the subsequent method design. The multi-layer winding can reduce the impact of current loss caused by the proximity effect, increase the system's fault operation capability and fault redundancy, and ensure that the system can continue to operate when some components fail.

[0043] like Figure 2 This is a flow chart of the common-mode noise optimization method for high-frequency transformers. The common-mode noise optimization method for high-frequency transformers is divided into four steps. Step 1 calculates the distributed capacitance of multi-layer windings. Step 2 sets the number of primary winding layers as the independent variable. Step 3 constructs an expression for the number of primary winding layers with respect to the primary and secondary distributed capacitances. Step 4 substitutes the secondary and primary turns ratio, and uses the analytical method to find monotonicity, thereby obtaining a specific primary winding layering strategy.

[0044] Among them, step 1 belongs to the content of distributed capacitance calculation, combined with Figure 3 The calculation method of distributed capacitance between primary and secondary windings is elaborated in detail.

[0045] First, calculate the electric field strength between the primary and secondary windings:

[0046]

[0047] According to the energy equivalence principle, the energy between the primary winding and the secondary winding is equivalent to the energy stored in the distributed capacitance between the primary winding and the secondary winding. The formula is:

[0048]

[0049] The distributed capacitance between the primary and secondary windings is obtained by combining them;

[0050]

[0051] U is the potential difference between the primary and secondary sides, d is the distance between the primary and secondary sides, p 1 is the number of turns of the primary winding facing the secondary winding, p is the total number of turns of the primary winding, U 1 is the primary winding voltage, U 2 is the secondary winding voltage, l is the average turn length of the winding, h is the primary winding height, ais the turns ratio of the secondary and primary windings, and ε is the dielectric constant.

[0052] In addition to the above calculation of the electric field strength by dividing the potential difference between the primary and secondary sides by the distance between the primary and secondary sides, the following calculation method can also be used:

[0053] 1. Model building: First, it is necessary to build a three-dimensional solid model of the transformer high-voltage coil, voltage-equalizing tube and voltage-equalizing ball. Considering the axisymmetric structure of the coil, a quarter of the coil can be taken for calculation;

[0054] 2. Finite element method: For the coil and the voltage-equalizing tube in the middle, the two-dimensional finite element method is used to calculate the distribution of the electric field and find the maximum electric field strength. At the same time, the calculation formula of the equivalent dielectric constant when the multi-layer oil-paper insulation structure is equivalent to a single medium is derived, and the equivalent dielectric constant is used to simplify the oil-paper insulation structure outside the coil and the oil-paper insulation near the transformer wall;

[0055] 3. Calculation of electric field strength: Use the three-dimensional finite element method to divide the solid model into upper and lower parts for electric field calculation, and find the maximum electric field strength and the location of the maximum field strength;

[0056] 4. Parameter setting: When performing finite element simulation, you need to add material properties to the model, such as core material, winding material (usually copper or aluminum), and insulation material. At the same time, according to the current distribution of the winding, add voltage excitation to each layer of winding;

[0057] 5. Solution and analysis: After adaptive meshing, the potential and electric field energy distribution in the transformer can be obtained, and according to the formula, the potential and electric field energy distribution in the transformer can be obtained, and the distributed capacitance can be calculated;

[0058] 6. Result acquisition: Through the above steps, the electric field strength distribution between the primary and secondary windings, as well as the maximum electric field strength value and its position can be obtained.

[0059] In summary, by establishing a model, applying the finite element method, setting parameters, solving and analyzing, we can obtain the electric field strength between the primary and secondary windings.

[0060] When calculating distributed capacitance, the following assumptions are usually made: the electric field is independent of the rate of change of magnetic induction, and the influence of displacement current is ignored; all turns of the winding are the same length, and the voltage is evenly distributed along the turns; slight changes in the dielectric constant of the insulating material are ignored; and only the distributed capacitance between adjacent conductor parts is considered.

[0061] Step 2 is about setting the independent variable. The main purpose of this step is to unify the variables to facilitate the implementation of steps 3 and 4. Instead of directly setting the number of layers of the primary winding as the independent variable, set the number of turns of the primary winding facing the secondary winding.p 1 Ratio to the total number of turns of the primary winding for x , the number of layers of the primary winding is , set the number of primary winding layers to t ,but , according to the number of turns of the primary winding facing the secondary winding p 1 Ratio to the total number of turns of the primary winding The primary winding height is derived as ，H It is the height of the primary winding before layering.

[0062] Step 3: Construct the expression of the primary winding layer number with respect to the primary and secondary side distributed capacitance, which is to replace the primary winding layer number in step 2 with t , primary winding height , the number of turns of the primary winding facing the secondary winding p 1 Ratio to the total number of turns of the primary winding , substituting into the distributed capacitance formula between the primary and secondary sides in step 1, we get:

[0063]

[0064] is the dielectric constant; the ratio of the number of turns of the primary winding facing the secondary winding to the total number of turns of the primary winding, as well as the number of layers and height of the primary winding, can affect the calculation of the distributed capacitance. If the winding is made of strip copper foil, the capacitance between the two windings can be directly calculated using the above formula. The winding structure and layout have a significant impact on the distributed capacitance. The low leakage inductance and large parasitic capacitance of the tight winding have become a contradiction. Reducing the leakage inductance can be achieved by tight coupling between the primary and secondary windings, that is, using a very small spacing in the winding structure and an interlaced winding method in the layout.

[0065] Step 4 is to substitute the specific value of the secondary-side and primary-side winding turns ratio a into the expression of the primary-side winding layers related to the primary-side and secondary-side distributed capacitance in step 3.

[0066] The expression of the number of primary winding layers in step 3 with respect to the primary and secondary distributed capacitances is calculated for monotonicity using a mathematical analytical method, and ultimately a specific layering strategy is obtained, thereby achieving the effect of suppressing the common-mode noise of the high-frequency transformer.

[0067] Specifically, the derivative of the primary winding layer number obtained in step 3 with respect to the primary and secondary distributed capacitance expression is taken, and the sign of the derivative is analyzed to determine the specific layering strategy. When the derivative sign is less than zero, increasing the number of layers can increase the distributed capacitance, which may increase the common mode noise, so the number of layers should be minimized; when the derivative sign is greater than zero, increasing the number of layers can reduce the distributed capacitance, which may reduce the common mode noise, so the number of layers can be appropriately increased.

[0068] By analyzing the monotonicity of the distributed capacitance expression through mathematical analysis, we can obtain a specific layering strategy to optimize the high-frequency transformer design and effectively suppress common-mode noise. This strategy needs to be specifically analyzed and adjusted in combination with actual transformer design parameters, such as the number of winding layers and turns.

[0069] In one embodiment, the turns ratio between the primary and secondary windings of the high-frequency transformer is set to 2:1.

[0070] The turns ratio a of the secondary and primary windings is 0.5. Substitute the number of primary winding layers into the expression of primary and secondary distributed capacitance in step 3.

[0071] After differentiation, we get the extreme point t=2, according to the monotonicity of the function.

[0072] When 1≤t≤2, the more layers the primary winding has, the larger the distributed capacitance C is, and the greater the common-mode interference is.

[0073] When 2≤t, the more layers the primary winding has, the smaller the distributed capacitance C is, and the smaller the common-mode interference is.

[0074] In another embodiment, the turns ratio between the primary and secondary windings of the high-frequency transformer is set to 10:1.

[0075] The turns ratio a of the secondary and primary windings is 0.1. Substitute the number of primary winding layers into the expression of primary and secondary distributed capacitance in step 3.

[0076] After differentiation, we get the extreme point t=1.27, according to the monotonicity of the function.

[0077] When 1.27≤t, the more layers the primary winding has, the smaller the distributed capacitance C is.

[0078] When the turns ratio of the primary and secondary windings of the high-frequency transformer is 10:1, the distributed capacitance at t=1 is greater than the distributed capacitance at t=2.

[0079] In general, when the turns ratio of the primary and secondary windings of the high-frequency transformer is 10:1, the more layers of the primary winding, the smaller the distributed capacitance and the smaller the common-mode noise.

[0080] Next, the influence of layering on the common mode noise of high-frequency transformers is verified by simulation, and ANSYS finite element simulation software is used for verification:

[0081] Figure 4 This is a high-frequency transformer model. The magnetic core and bracket parts are hidden. The primary winding of N1 has 70 turns, divided into 3 layers, and the secondary winding of N4 has 8 turns.

[0082] Figure 5 This is a layered high-frequency transformer model. At this time, the primary winding of N1 has 4 layers.

[0083] The distributed capacitance between the primary winding and the secondary winding before and after layering is obtained through finite element simulation software as shown in Table 1.

[0084] Table 1 Distributed capacitance value table

[0085] Before stratification After stratification Distributed capacitance (pF) 3.036 2.487

[0086] Finite element simulation shows that when the turns ratio is 70:8, the primary winding is changed from 3 layers to 4 layers, the distributed capacitance between the primary and secondary windings is reduced, and the common-mode noise of the high-frequency transformer is suppressed.

[0087] The present invention also discloses a device for calculating distributed capacitance of a high-frequency transformer and optimizing common-mode noise, the device comprising:

[0088] A calculation unit is used to obtain the electric field strength between the primary and secondary windings; and the energy between the primary and secondary windings is equivalent to the energy stored in the distributed capacitance between the primary and secondary windings; and the distributed capacitance of the multi-layer winding is calculated from the electric field strength and the energy stored in the distributed capacitance between the windings;

[0089] Conversion unit, set the number of turns of the primary winding facing the secondary winding p 1 Ratio to the total number of turns of the primary winding is x; the number of layers of the primary winding is , set the number of primary winding layers to t , then the primary winding height is , H is the height of the primary winding before stratification;

[0090] The building unit consists of a primary winding facing the secondary winding turns. p 1 Substitute the ratio of the total number of turns of the primary winding, the number of layers of the primary winding, and the height of the primary winding into the distributed capacitance of the multilayer winding to obtain the capacitance expression of the primary winding layers with respect to the primary and secondary sides;

[0091] The strategy analysis unit calculates the monotonicity of the primary winding layer number expressed with respect to the primary and secondary side distributed capacitances according to the secondary and primary winding turns ratio, and obtains the corresponding stratification strategy according to the monotonicity; when the primary winding layer number is not less than the extreme value point, the more primary winding stratification layers there are, the smaller the distributed capacitance is, and the smaller the common mode noise is.

[0092] Preferably, the calculation unit also includes: a field strength acquisition unit, which acquires the electric field strength between the primary and secondary windings; and an energy conversion unit, which, according to the energy equivalence principle, converts the energy between the primary and secondary windings into energy stored in the distributed capacitance between the primary and secondary windings.

[0093] The device of the present invention also includes:

[0094] at least one processor; and a memory in communication with the at least one processor; wherein,

[0095] The memory stores a computer program executable by at least one processor, and the computer program is executed by at least one processor.

[0096] The present invention calculates the distributed capacitance of multilayer windings, sets the number of primary winding layers as an independent variable and constructs an expression of the number of primary winding layers with respect to the primary and secondary distributed capacitances; by substituting the secondary and primary turns ratios, the analytical method is used to find monotonicity, thereby obtaining a specific primary winding layering strategy. When the derivative sign is less than zero, increasing the number of layers can increase the distributed capacitance, thereby possibly increasing the common mode noise, therefore, the number of layers should be minimized; when the derivative sign is greater than zero, increasing the number of layers can reduce the distributed capacitance, thereby possibly reducing the common mode noise, therefore, the number of layers can be appropriately increased.

[0097] Therefore, the present invention can reduce the distributed capacitance between the primary side and the secondary side by changing the number of primary side winding layers without adding other reverse windings and shielding layers. This solves the harm of common mode noise transmitted by high frequency transformers in power converter systems, greatly weakens the common mode noise signals received by input and output cable ends, and significantly weakens the electromagnetic radiation interference of common mode noise of power converter system cables.

[0098] Finally, it should be noted that the above embodiments are only specific implementations of the present invention, which are used to illustrate the technical solutions of the present invention, rather than to limit them. The protection scope of the present invention is not limited thereto. Although the present invention is described in detail with reference to the above embodiments, those skilled in the art should understand that any person skilled in the art can still modify the technical solutions recorded in the above embodiments within the technical scope disclosed by the present invention, or can easily think of changes, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A method for calculating distributed capacitance of a high-frequency transformer and optimizing common-mode noise, the method comprising: Step 1: Obtain the electric field strength between the primary and secondary windings; And the energy between the primary winding and the secondary winding is equivalent to the energy stored in the distributed capacitance between the primary winding and the secondary winding; The distributed capacitance of the multilayer winding is calculated from the electric field strength and the energy stored in the distributed capacitance between the side windings; Step 2: Set the number of turns of the primary winding facing the secondary winding p 1 Ratio of the total number of turns P of the primary winding is x; the number of layers of the primary winding is , set the number of primary winding layers to t , then the primary winding height is , H is the height of the primary winding before stratification; Step 3: Count the turns of the secondary winding from the primary winding p Substitute the ratio of 1 to the total number of turns of the primary winding, the number of layers of the primary winding, and the height of the primary winding into the distributed capacitance of the multilayer winding to obtain the capacitance expression of the primary winding layers with respect to the primary and secondary sides; Step 4: Calculate the monotonicity of the number of primary winding layers expressed with respect to the capacitances distributed on the primary and secondary sides according to the turns ratio of the secondary and primary windings, and obtain the corresponding layering strategy based on the monotonicity; When the number of primary winding layers is not less than the extreme value point, the more primary winding layers there are, the smaller the distributed capacitance is, and the smaller the common mode noise is; The specific process of calculating the distributed capacitance of the multilayer winding from the electric field strength and the energy stored in the distributed capacitance between the side windings is: 1) First calculate the electric field strength between the primary and secondary windings for: ； 2) According to the energy equivalence principle, the energy between the primary winding and the secondary winding is equivalent to the energy stored in the distributed capacitance between the primary winding and the secondary winding. The formula is: ； 3) The distributed capacitance between the primary and secondary windings is obtained by combining: ； U is the potential difference between the primary and secondary sides, d is the distance between the primary and secondary sides, p 1 is the number of turns of the primary winding facing the secondary winding, p is the total number of turns of the primary winding, U 1 is the primary winding voltage, U 2 is the secondary winding voltage, l is the average turn length of the winding, h is the primary winding height, a is the turns ratio of the secondary and primary windings.

2. A method for calculating distributed capacitance and optimizing common-mode noise of a high-frequency transformer according to claim 1, wherein: The expression of the primary winding layer number for the primary and secondary side distributed capacitance is as follows: t , primary winding height , the number of turns of the primary winding facing the secondary winding p 1 Ratio of the total number of turns of the primary winding , substituting into the distributed capacitance formula between the primary and secondary sides: 。 3. According to the method for calculating distributed capacitance and optimizing common-mode noise of a high-frequency transformer as described in claim 2, the turns ratio of the primary and secondary windings of the high-frequency transformer is 10:

1. When the number of layers of the primary winding is not less than 1.27, the more layers of the primary winding, the smaller the distributed capacitance and the smaller the common-mode noise.

4. According to the method for calculating distributed capacitance and optimizing common-mode noise of a high-frequency transformer as described in claim 2, the turns ratio of the primary and secondary windings of the high-frequency transformer is 2:

1. When the number of layers of the primary winding is greater than or equal to 1 and less than or equal to 2, the more layers of the primary winding, the greater the distributed capacitance C and the greater the common-mode interference.

5. According to the method for calculating distributed capacitance and optimizing common-mode noise of a high-frequency transformer as described in claim 4, the turns ratio of the primary and secondary windings of the high-frequency transformer is 2:

1. When the number of layers of the primary winding is greater than 2, the more layers of the primary winding, the smaller the distributed capacitance C, and the smaller the common-mode interference.

6. A device for calculating distributed capacitance and optimizing common-mode noise of a high-frequency transformer, applied to the method for calculating distributed capacitance and optimizing common-mode noise of a high-frequency transformer according to any one of claims 1 to 5, the device comprising: A calculation unit, for obtaining the electric field strength between the primary side and the secondary side windings; And the energy between the primary winding and the secondary winding is equivalent to the energy stored in the distributed capacitance between the primary winding and the secondary winding; The distributed capacitance of the multilayer winding is calculated from the electric field strength and the energy stored in the distributed capacitance between the side windings; Conversion unit, set the number of turns of the primary winding facing the secondary winding p 1 Ratio of the total number of turns P of the primary winding is x; the number of layers of the primary winding is , set the number of primary winding layers to t , then the primary winding height is , H is the height of the primary winding before stratification; The building unit consists of a primary winding facing the secondary winding turns. p Substitute the ratio of 1 to the total number of turns of the primary winding, the number of layers of the primary winding, and the height of the primary winding into the distributed capacitance of the multilayer winding to obtain the capacitance expression of the primary winding layers with respect to the primary and secondary sides; The strategy analysis unit calculates the monotonicity of the primary winding layer number expressed with respect to the primary and secondary side distributed capacitances according to the secondary and primary winding turns ratio, and obtains the corresponding stratification strategy according to the monotonicity; when the primary winding layer number is not less than the extreme value point, the more primary winding stratification layers there are, the smaller the distributed capacitance is, and the smaller the common mode noise is.

7. A high-frequency transformer distributed capacitance calculation and common-mode noise optimization device according to claim 6, wherein: The computing unit also includes: A field strength acquisition unit, for acquiring the electric field strength between the primary and secondary windings; The energy conversion unit converts the energy between the primary winding and the secondary winding into the energy stored in the distributed capacitance between the primary winding and the secondary winding according to the energy equivalence principle.

8. A high-frequency transformer distributed capacitance calculation and common-mode noise optimization system, characterized in that: The system comprises: at least one processor; and a memory in communication with the at least one processor; wherein, The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can execute a high-frequency transformer distributed capacitance calculation and common-mode noise optimization method as described in any one of claims 1-5.

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