Transformer capacitance calculation method and system and power generation system construction method

Abstract

The invention discloses a transformer capacitance calculation method. The method comprises the steps of firstly obtaining a corresponding relation between a first basic capacitor bank of a transformer product and a first technical parameter of the transformer product; obtaining a second basic capacitor group of the target transformer according to a second technical parameter of the target transformer and the corresponding relation; and combining the capacitance values in the second basic capacitor bank of the target transformer to obtain the required capacitance data of the target transformer. The transformer capacitance calculation method is rapid in calculation process, high in result accuracy and capable of meeting the timeliness requirement. The invention also provides a transformer capacitance calculation system and a power generation system construction method.

Description

Technical Field

[0001] The present invention belongs to the technical field of transformers, and particularly relates to a method for calculating transformer capacitance, a system, and a method for constructing a power generation system. Background Art

[0002] A transformer is an important electrical device indispensable in the power system. Various parameters of the transformer often need to be provided by the transformer manufacturer in advance during the design of the power system to facilitate the coordination and selection of other power equipment. Among them, the transformer capacitance value is one of the most important parameters. For example, when selecting the neutral point equipment of a generator in a power plant, the user or the power design institute needs to calculate the capacitive current of the generator neutral point. In addition to the single-phase-to-ground capacitance of the generator stator coil and the single-phase-to-ground capacitance of the generator outlet bus, the single-phase-to-ground capacitance of the low-voltage side of the step-up transformer and the single-phase-to-ground capacitance of the high-voltage side of the auxiliary transformer are also required. These transformer capacitance data need to be provided by the transformer manufacturer in advance.

[0003] It can be seen that users or design institutes often require the provision of transformer capacitance data during the transformer scheme design or even during the transformer bidding stage. However, the existing calculation methods often can only perform finite element analysis calculations to obtain data during or after the transformer design process, or obtain data by multiplying the capacitance between coils (windings) by a coefficient. On the one hand, it cannot meet the timeliness requirement of providing data in advance, and on the other hand, the calculation accuracy is not enough. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a method for calculating transformer capacitance, which has a fast calculation process, high result accuracy, and can meet the timeliness requirement, aiming at the above deficiencies in the prior art. The present invention also provides a system for calculating transformer capacitance and a method for constructing a power generation system.

[0005] The present invention provides a method for calculating transformer capacitance, including the following steps:

[0006] Obtain the correspondence between the first basic capacitor group of the transformer product and the first technical parameters of the transformer product;

[0007] Obtain the second basic capacitor group of the target transformer according to the second technical parameters of the target transformer and the correspondence;

[0008] Combine the capacitance values in the second basic capacitor group of the target transformer to obtain the required capacitance data of the target transformer.

[0009] Further, the correspondence includes:

[0010] Calculation formulas for the capacitance value of the outermost winding of the transformer to the transformer oil tank, the capacitance value of the innermost winding of the transformer to the transformer iron core, and the capacitance value between adjacent windings of the transformer.

[0011] Further, the calculation formula for the capacitance value of the outermost winding of the transformer to the transformer oil tank is:

[0012] C1 = α·S + β

[0013] Wherein, C1 is the capacitance value of the outermost winding of the transformer to the transformer oil tank, S is the transformer capacity, and α and β are both coefficients obtained from the variation law of each capacitance value in the first basic capacitor group with the first technical parameter, and are both related to the winding distribution form of the transformer and the voltage level of the outermost winding.

[0014] Further, before obtaining the corresponding relationship between the first basic capacitor group of the transformer product and the first technical parameter of the transformer product, the method further includes the following steps:

[0015] Obtain the capacitance test data of the transformer product, and classify the capacitance test data of the transformer product according to the winding distribution form and the winding voltage level;

[0016] The calculation formula for the capacitance value of the outermost winding of the transformer to the transformer oil tank includes the calculation formulas for each winding voltage level in the following various winding distribution forms:

[0017] ① When the outermost winding of the transformer is a high-voltage winding and does not have a tap-changing winding:

[0018] When the voltage level of the high-voltage winding of the transformer is 35 kV and below, C1 = 0.0013S + 708;

[0019] When the voltage level of the high-voltage winding of the transformer is 110 kV, C1 = 0.0076S + 779;

[0020] When the voltage level of the high-voltage winding of the transformer is 220 kV, C1 = 0.0023S + 1078;

[0021] When the voltage level of the high-voltage winding of the transformer is 330 kV, C1 = 0.0022S + 1054;

[0022] When the voltage level of the high-voltage winding of the transformer is 500 kV, C1 = 0.002S + 1354;

[0023] When the voltage level of the high-voltage winding of the transformer is 750 kV, C1 = 0.0009S + 2710;

[0024] ② When the outermost winding of the transformer is a high-voltage winding and has a high-voltage tap-changing winding:

[0025] When the voltage level of the high-voltage winding of the transformer is 35 kV or less, C1 = 0.0082S + 544;

[0026] When the voltage level of the high-voltage winding of the transformer is 110 kV, C1 = 0.0038S + 1063;

[0027] When the voltage level of the high-voltage winding of the transformer is 220 kV, C1 = 0.0033S + 1336;

[0028] When the voltage level of the high-voltage winding of the transformer is 330 kV, C1 = 0.003S + 1496;

[0029] When the voltage level of the high-voltage winding of the transformer is 500 kV, C1 = 0.0033S + 1806;

[0030] When the voltage level of the high-voltage winding of the transformer is 750 kV, C1 = 0.0013S + 3658;

[0031] ③ When the outermost winding of the transformer is the high-voltage winding and has a high-tap winding and a middle-tap winding:

[0032] When the voltage level of the high-voltage winding of the transformer is 35 kV or less, C1 = 0.0088S + 490;

[0033] When the voltage level of the high-voltage winding of the transformer is 110 kV, C1 = 0.0041S + 954;

[0034] When the voltage level of the high-voltage winding of the transformer is 220 kV, C1 = 0.0036S + 1193;

[0035] When the voltage level of the high-voltage winding of the transformer is 330 kV, C1 = 0.0032S + 1348;

[0036] When the voltage level of the high-voltage winding of the transformer is 500 kV, C1 = 0.0036S + 1627;

[0037] When the voltage level of the high-voltage winding of the transformer is 750 kV, C1 = 0.0014S + 3295;

[0038] ④ When the outermost winding of the transformer is the low-voltage winding:

[0039] When the voltage level of the low-voltage winding of the transformer is 35 kV or less, C1 = 0.0051S + 117.

[0040] Furthermore, the calculation formula for the capacitance value of the innermost winding of the transformer to the transformer core is:

[0041] C2 = γ·εH / ln(R2 / R1)

[0042] Among them, C2 is the capacitance value of the innermost winding of the transformer to the transformer core, γ is the coefficient obtained from the variation law of each capacitance value in the first basic capacitance group with the first technical parameter, and is related to the winding distribution form of the transformer, ε is the relative permittivity of the main air duct material between the innermost winding and the core, H is the height of the innermost winding, R1 is the radius of the core, and R2 is the inner radius of the innermost winding.

[0043] Furthermore, the capacitance value calculation formula between two adjacent windings of the transformer is:

[0044] Cn = τ·ξL / ln(R4 / R3)

[0045] Among them, Cn is the capacitance value between two adjacent windings of the transformer, τ is the coefficient obtained from the variation law of each capacitance value in the first basic capacitance group with the first technical parameter, and is related to the winding distribution form of the transformer, ξ is the relative permittivity of the main air duct material between two adjacent windings, L is the average height of two adjacent windings, R3 is the outer radius of the inner winding among two adjacent windings, and R4 is the inner radius of the outer winding among two adjacent windings.

[0046] Furthermore, the second basic capacitance group of the target transformer includes: the capacitance value of the outermost winding of the target transformer to the oil tank, the capacitance value of the innermost winding to the core, and the capacitance value between two adjacent windings;

[0047] The combination of each capacitance value in the second basic capacitance group of the target transformer to obtain the required capacitance data of the target transformer specifically includes: according to the winding distribution form of the target transformer, combining the capacitance value of the outermost winding of the target transformer to the oil tank, the capacitance value of the innermost winding to the core, and the capacitance value between two adjacent windings to obtain the single-phase capacitance value of each winding of the target transformer to the ground and the single-phase capacitance value between windings, so as to obtain the capacitance data of the target transformer.

[0048] Furthermore, when the target transformer is classified as a two-winding transformer according to the winding distribution form, and the core, low-voltage winding, high-voltage winding, and oil tank are arranged in sequence along the radial direction, the capacitance values in the second basic capacitance group are set respectively as:

[0049] The capacitance value C1 of the high-voltage winding to the oil tank, the capacitance value C2 of the low-voltage winding to the core, and the capacitance value C3 of the high-voltage winding to the low-voltage winding;

[0050] Then the combination of each capacitance value in the second basic capacitance group of the target transformer to obtain the required capacitance data of the target transformer specifically includes:

[0051] Based on C 高地 = C1 + C3 to obtain the single-phase capacitance C of the high-voltage winding to the ground 高地 ;

[0052] According to C 低地 = C2 + C3 to obtain the single-phase capacitance C of the low-voltage winding to the ground 低地 ;

[0053] According to C 高低 = C3 to obtain the single-phase capacitance C of the high-voltage winding to the low-voltage winding 高低 ;

[0054] According to C 高低地 = C1 + C2 to obtain the single-phase capacitance C of the high-voltage winding and the low-voltage winding to the ground 高低地 .

[0055] Furthermore, the target transformer is classified as a three-winding transformer according to the winding distribution form. When the iron core, low-voltage winding, medium-voltage winding, high-voltage winding, and oil tank are arranged in the radial direction in sequence, the capacitance values in the second basic capacitor group are set as follows:

[0056] The capacitance value C1 of the high-voltage winding to the oil tank, the capacitance value C2 of the low-voltage winding to the iron core, the capacitance value C3 of the medium-voltage winding to the low-voltage winding, and the capacitance value C4 of the high-voltage winding to the medium-voltage winding

[0057] Then, combining the capacitance values in the second basic capacitor group of the target transformer to obtain the capacitance data of the required target transformer specifically includes:

[0058] According to C 高地 = C1 + C4 to obtain the single-phase capacitance C of the high-voltage winding to the ground 高地 ;

[0059] According to C 中地 = C3 + C4 to obtain the single-phase capacitance C of the medium-voltage winding to the ground 中地 ;

[0060] According to C 低地 = C2 + C3 to obtain the single-phase capacitance C of the low-voltage winding to the ground 低地 ;

[0061] According to C 高中地 = C1 + C3 to obtain the single-phase capacitance C of the high-voltage winding and the medium-voltage winding to the ground 高中地 ;

[0062] According to C 高中低地 = C1 + C2 to obtain the single-phase capacitance C of the high-voltage winding, the medium-voltage winding, and the low-voltage winding to the ground 高中低地 ;

[0063] According to C 高中 = C4 to obtain the single-phase capacitance C of the high-voltage winding to the medium-voltage winding 高中 ;

[0064] According to C 中低= C3 to obtain the single-phase capacitance C of the medium-voltage winding with respect to the low-voltage winding 中低 ;

[0065] Based on C 高低 = (C3 × C4) / (C3 + C4) to obtain the single-phase capacitance C of the high-voltage winding with respect to the low-voltage winding 高低 .

[0066] Furthermore, when the target transformer is classified as an autotransformer according to the winding distribution form, and the iron core, low-voltage winding, medium-voltage winding, high-voltage winding, and oil tank are arranged in sequence along the radial direction, the capacitance values in the second basic capacitance group are set respectively as:

[0067] The capacitance value C1 of the high-voltage winding with respect to the oil tank, the capacitance value C2 of the low-voltage winding with respect to the iron core, and the capacitance value C3 of the medium-voltage winding with respect to the low-voltage winding

[0068] Then, combining the capacitance values in the second basic capacitance group of the target transformer to obtain the required capacitance data of the target transformer specifically includes:

[0069] Based on C 高中地 = C1 + C3 to obtain the single-phase capacitance C of the high-voltage winding and the medium-voltage winding with respect to the ground 高中地 ;

[0070] Based on C 低地 = C2 + C3 to obtain the single-phase capacitance C of the low-voltage winding with respect to the ground 低地 ;

[0071] Based on C 高中低 = C3 to obtain the single-phase capacitance C of the high-voltage winding and the medium-voltage winding with respect to the low-voltage winding 高中低 ;

[0072] Based on C 高中低地 = C1 + C2 to obtain the single-phase capacitance C of the high-voltage winding, the medium-voltage winding, and the low-voltage winding with respect to the ground 高中低地 .

[0073] Furthermore, when the target transformer is classified as a split transformer according to the winding distribution form, and the iron core, the first low-voltage winding, the second low-voltage winding, the high-voltage winding, and the oil tank are arranged in sequence along the radial direction, the capacitance values in the second basic capacitance group are set respectively as:

[0074] The capacitance value C1 of the high-voltage winding with respect to the oil tank, the capacitance value C2 of the first low-voltage winding with respect to the iron core, and the capacitance value C3 of the high-voltage winding with respect to the first low-voltage winding

[0075] Then, combining the capacitance values in the second basic capacitance group of the target transformer to obtain the required capacitance data of the target transformer specifically includes:

[0076] Based on C 高地= C1 + 2 × C3 to obtain the single-phase capacitance C of the high-voltage winding to the ground 高地 ;

[0077] According to C 低1地 = C2 + C3 to obtain the single-phase capacitance C of the first low-voltage winding to the ground 低1地 ;

[0078] According to C 低2地 = C2 + C3 to obtain the single-phase capacitance C of the second low-voltage winding to the ground 低2地 ;

[0079] According to C 高低1地 = C1 + C2 + C3 to obtain the single-phase capacitance C of the high-voltage winding and the first low-voltage winding to the ground 高低1地 ;

[0080] According to C 高低1低2地 = C1 + 2*C2 to obtain the single-phase capacitance C of the high-voltage winding, the first low-voltage winding and the second low-voltage winding to the ground 高低1低2地 ;

[0081] According to C 高低1 = C3 to obtain the single-phase capacitance C of the high-voltage winding to the first low-voltage winding 高低1 ;

[0082] According to C 高低2 = C3 to obtain the single-phase capacitance C of the high-voltage winding to the second low-voltage winding 高低 2.

[0083] The present invention also provides a method for constructing a power generation system, including the following steps:

[0084] Use the above transformer capacitance calculation method to calculate the capacitance data of the target transformer;

[0085] Select the matching equipment in the power generation system according to the capacitance data of the target transformer, so as to obtain the construction plan of the power generation system;

[0086] Construct the power generation system according to the construction plan of the power generation system.

[0087] The present invention also provides a transformer capacitance calculation system, which can implement the above transformer capacitance calculation method. The system includes: a fitting module for obtaining the correspondence between the first basic capacitance group of the transformer product and the first technical parameters of the transformer product, a first calculation module electrically connected to the fitting module for obtaining the second basic capacitance group of the target transformer according to the second technical parameters of the target transformer and the correspondence, and a second calculation module electrically connected to the first calculation module for combining the capacitance values in the second basic capacitance group of the target transformer to obtain the required capacitance data of the target transformer.

[0088] The transformer capacitance calculation method of the present invention first obtains the correspondence between the first basic capacitance group of existing transformer products and the first technical parameters, then substitutes the second technical parameters of the target transformer into the correspondence to obtain the second basic capacitance group, and finally the obtained capacitance values can be combined to obtain the required capacitance data.

[0089] It can be seen that the present invention provides a new capacitance calculation method. This calculation method can first establish the correspondence between the historical product technical parameters and capacitance data through existing transformer equipment. Therefore, at the initial stage of the scheme design or the bidding stage, the basic capacitance group can be quickly matched and calculated based on the key parameters of the conceptual design. Compared with the traditional method in which modeling is carried out after waiting for the detailed design to be completed and then finite element simulation is carried out, this method greatly advances the capacitance data delivery node and can meet the time limit requirements of technical responses.

[0090] Moreover, compared with the traditional coefficient estimation method that is greatly affected by the experience of engineers and has a high dispersion of calculation results among different personnel, this method quantifies the correlation between the measured data of historical products and technical parameters, making the error of early estimation lower, and the calculation results are traceable, rather than simply multiplying by a fixed coefficient, effectively improving the accuracy of the calculation results.

[0091] In addition, after obtaining the correspondence, this method can also be used for the capacitance calculation of transformers in the early stage of various designs, and the calculation process is rapid, the results are accurate, and it can also meet the timeliness requirements. Description of the Drawings

[0092] Figure 1 It is a schematic flow chart of the transformer capacitance calculation method in Embodiment 2 of the present invention for a three-winding transformer;

[0093] Figure 2 It is a schematic diagram of the winding distribution form of the three-winding transformer applied by the transformer capacitance calculation method in Embodiment 2 of the present invention. Detailed Embodiments

[0094] Next, the technical solutions in the present invention will be clearly and completely described in conjunction with the drawings in the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of the present invention.

[0095] In the description of the present invention, it should be noted that the terms "upper", "lower", etc. indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of description and simplification, rather than indicating or implying that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0096] In the description of the present invention, the terms "first", "second", "third" are only used for descriptive purposes and should not be construed as indicating or implying relative importance.

[0097] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "connection", "setting", "installation", "fixing", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0098] Embodiment 1

[0099] The transformer capacitance calculation method of this embodiment includes the following steps:

[0100] Obtain the correspondence between the first basic capacitor group of the transformer product and the first technical parameters of the transformer product;

[0101] Obtain the second basic capacitor group of the target transformer according to the second technical parameters of the target transformer and the correspondence;

[0102] Combine the capacitance values in the second basic capacitor group of the target transformer to obtain the capacitance data of the required target transformer.

[0103] This transformer capacitance calculation method provides a new capacitance calculation method. This calculation method can first establish the correspondence between the historical product technical parameters and the capacitance data through the existing transformer equipment. Therefore, at the initial stage of the scheme design or the bidding stage, the basic capacitor group can be quickly matched and calculated based on the key parameters of the conceptual design.

[0104] Compared with the traditional method in which it is necessary to wait until the detailed design is completed and then model, and then perform finite element simulation (requiring complete geometric modeling and mesh generation), this method greatly advances the capacitance data delivery node, can meet the time limit requirements of technical responses, and does not require special simulation software and high-performance computing resources. While maintaining reasonable accuracy, the calculation efficiency is increased several times.

[0105] Moreover, compared with the traditional coefficient estimation method that is greatly affected by engineers' experience and has a high dispersion of calculation results among different personnel, this method quantifies the correlation between the measured data of historical products and technical parameters, resulting in lower errors in early estimation, and the calculation results are traceable. Instead of simply multiplying by a fixed coefficient, it effectively improves the accuracy of the calculation results.

[0106] In addition, after obtaining the corresponding relationship, this method can also be used for the calculation of transformer capacitance in the early stage of various designs. The calculation process is rapid, the results are accurate, and it can also meet the timeliness requirements, effectively solving the pain point that it is difficult to obtain accurate results due to the lack of reference data in the current early stage of design. This precision control strategy that focuses on the early stage of design effectively balances efficiency and accuracy in engineering practice and ensures data synchronization among multiple parties such as the production side and the user side.

[0107] In this embodiment, the corresponding relationship that can be obtained through the first basic capacitance group of the transformer product and the first technical parameters of the transformer product specifically includes: the capacitance value calculation formula of the outermost winding of the transformer to the transformer tank, the capacitance value calculation formula of the innermost winding of the transformer to the transformer core, and the capacitance value calculation formula between adjacent two windings of the transformer.

[0108] The specific process is as follows: Obtain the capacitance values of each winding of the transformer product to the ground and the capacitance values between windings according to the capacitance test data of the transformer product, that is, obtain the actual capacitance values of each winding of the transformer product. This data is a value that can be directly obtained through the capacitance test of existing transformer products.

[0109] Decompose the capacitance values of each winding of the transformer product to the ground and the capacitance values between windings to obtain the first basic capacitance group of the transformer product; specifically, decompose the actual capacitance values of each winding of the transformer product, that is, decompose the capacitance of each winding to the ground and the capacitance between windings into the capacitance of the innermost winding of the transformer product (structurally arranged as the core, each winding, and the tank in the radial direction) to the core, winding to winding, and the outermost winding to the tank, so as to obtain the capacitance values of the foregoing independent parts.

[0110] Obtain the variation law of each capacitance value in the first basic capacitance group with the first technical parameter, so as to obtain the calculation formulas of the above capacitance values as the corresponding relationship. In this embodiment, further specifically:

[0111] 1. Summarize the capacitance values of the outermost winding of the transformer to the tank obtained by decomposition, and summarize the functional relationship between the capacitance values of this part and the winding distribution form of the transformer, the transformer capacity, and the winding voltage level, obtain the capacitance value calculation formula of this part, and then obtain the capacitance of the outermost winding of the target transformer to the tank according to this calculation formula.

[0112] II. Calculate the relative permittivity of the main air duct material between the innermost winding and the iron core of the transformer product based on the cardboard thickness, number of spacers, and width of spacers in the main air duct. Then, summarize the capacitance values between the innermost winding and the iron core of the decomposed transformer product, and obtain the functional relationship between the capacitance values of this part and the relative permittivity of the main air duct material, the radius of the iron core, the inner radius of the innermost winding, and the height of the innermost winding, so as to obtain the calculation formula for the capacitance value of this part. Subsequently, calculate the capacitance between the innermost winding and the iron core of the target transformer according to this calculation formula;

[0113] III. Calculate the relative permittivity of the main air duct material between two adjacent windings of the transformer product based on the cardboard thickness, number of spacers, and width of spacers in the main air duct. Then, summarize the capacitance values between two adjacent windings of the decomposed transformer product, and obtain the functional relationship between the capacitance values of this part and the relative permittivity of the main air duct material, the outer radius of the inner winding, the inner radius of the outer winding, and the average height of the two windings, so as to obtain the calculation formula for the capacitance value of this part. Subsequently, calculate the capacitance between two adjacent windings of the target transformer according to this calculation formula.

[0114] In this embodiment, the calculation formula for the capacitance between the outermost winding of the transformer and the transformer oil tank is:

[0115] C1 = α·S + β

[0116] Wherein, C1 is the capacitance between the outermost winding of the transformer and the transformer oil tank, S is the transformer capacity, and α and β are coefficients obtained from the variation law of each capacitance value in the first basic capacitance group with respect to the first technical parameter, and are both related to the winding distribution form of the transformer and the voltage level of the outermost winding.

[0117] In this embodiment, before obtaining the corresponding relationship between the first basic capacitance group of the transformer product and the first technical parameter of the transformer product, the method further includes the following steps:

[0118] Obtain or collect the capacitance test data of the produced transformer products, and classify the capacitance test data of the transformer products according to the winding distribution form and the winding voltage level. The transformer capacity can also be used as a classification basis during classification to ensure the degree of subdivision; the classification processing enables the corresponding relationship (calculation formula) obtained in this way to adapt to the characteristic differences of different transformer structure schemes and avoid the systematic deviation caused by traditional overall estimation, making it more valuable for engineering reference.

[0119] Therefore, the calculation formula for the capacitance between the outermost winding of the transformer and the transformer oil tank includes the calculation formulas for each winding voltage level in the following various winding distribution forms:

[0120] ① When the outermost winding of the transformer is the high-voltage winding and there is no voltage regulating winding, let the corresponding transformer capacity be S (unit: kVA), and the single-phase capacitance of the high-voltage winding to the oil tank be C1 (unit: pF), then:

[0121] When the voltage level of the high-voltage winding of the transformer is 35 kV and below, C1 = 0.0013S + 708;

[0122] When the voltage level of the high-voltage winding of the transformer is 110 kV, C1 = 0.0076S + 779;

[0123] When the voltage level of the high-voltage winding of the transformer is 220 kV, C1 = 0.0023S + 1078;

[0124] When the voltage level of the high-voltage winding of the transformer is 330 kV, C1 = 0.0022S + 1054;

[0125] When the voltage level of the high-voltage winding of the transformer is 500 kV, C1 = 0.002S + 1354;

[0126] When the voltage level of the high-voltage winding of the transformer is 750 kV, C1 = 0.0009S + 2710;

[0127] ② When the outermost winding of the transformer is the high-voltage winding and there is a high-voltage regulating winding (i.e., a high-voltage regulating coil, the following medium-voltage regulating winding is the medium-voltage regulating coil, which is a conventional setting method in this field and will not be elaborated here), let the corresponding transformer capacity be S (unit: kVA), and the single-phase capacitance of the high-voltage winding to the oil tank be C1 (unit: pF), then:

[0128] When the voltage level of the high-voltage winding of the transformer is 35 kV and below, C1 = 0.0082S + 544;

[0129] When the voltage level of the high-voltage winding of the transformer is 110 kV, C1 = 0.0038S + 1063;

[0130] When the voltage level of the high-voltage winding of the transformer is 220 kV, C1 = 0.0033S + 1336;

[0131] When the voltage level of the high-voltage winding of the transformer is 330 kV, C1 = 0.003S + 1496;

[0132] When the voltage level of the high-voltage winding of the transformer is 500 kV, C1 = 0.0033S + 1806;

[0133] When the voltage level of the high-voltage winding of the transformer is 750 kV, C1 = 0.0013S + 3658;

[0134] ③ When the outermost winding of the transformer is the high-voltage winding and is equipped with a high-tap winding and a medium-tap winding, assuming the corresponding transformer capacity is S (unit: kVA) and the single-phase capacitance of the high-voltage winding to the oil tank is C1 (unit: pF), then:

[0135] When the voltage level of the high-voltage winding of the transformer is 35 kV and below, C1 = 0.0088S + 490;

[0136] When the voltage level of the high-voltage winding of the transformer is 110 kV, C1 = 0.0041S + 954;

[0137] When the voltage level of the high-voltage winding of the transformer is 220 kV, C1 = 0.0036S + 1193;

[0138] When the voltage level of the high-voltage winding of the transformer is 330 kV, C1 = 0.0032S + 1348;

[0139] When the voltage level of the high-voltage winding of the transformer is 500 kV, C1 = 0.0036S + 1627;

[0140] When the voltage level of the high-voltage winding of the transformer is 750 kV, C1 = 0.0014S + 3295;

[0141] ④ When the outermost winding of the transformer is the low-voltage winding, assuming the corresponding transformer capacity is S (unit: kVA) and the single-phase capacitance of the low-voltage winding to the oil tank is C1 (unit: pF), then:

[0142] When the voltage level of the low-voltage winding of the transformer is 35 kV and below, C1 = 0.0051S + 117.

[0143] In this embodiment, the calculation formula for the capacitance value of the innermost winding of the transformer to the transformer core is:

[0144] C2 = γ·εH / ln(R2 / R1)

[0145] Among them, C2 is the capacitance value of the innermost winding of the transformer to the transformer core, γ is the coefficient obtained from the variation law of the capacitance values in the first basic capacitor group with respect to the first technical parameter and is related to the winding distribution form of the transformer, ε is the relative dielectric constant of the main air channel material between the innermost winding and the core, H is the height of the innermost winding, R1 is the radius of the core, and R2 is the inner radius of the innermost winding.

[0146] In this embodiment, the calculation formula for the capacitance value between two adjacent windings of the transformer is:

[0147] Cn = τ·ξL / ln(R4 / R3)

[0148] Among them, Cn is the capacitance value between two adjacent windings of the transformer, τ is a coefficient obtained from the variation law of the capacitance values in the first basic capacitor group with respect to the first technical parameter, and is related to the winding distribution form of the transformer, ξ is the relative permittivity of the main air duct material between two adjacent windings, L is the average height of two adjacent windings, R3 is the outer radius of the inner winding among two adjacent windings, and R4 is the inner radius of the outer winding among two adjacent windings.

[0149] In this embodiment, the relative permittivity of the main air duct material is obtained from the cardboard thickness of the main air duct, the number of spacers in the main air duct, and the width of the spacers in the transformer technical parameters.

[0150] In this embodiment, the second basic capacitor group of the target transformer specifically includes: the capacitance value of the outermost winding of the target transformer to the oil tank, the capacitance value of the innermost winding to the iron core, and the capacitance value between two adjacent windings;

[0151] Combining the capacitance values in the second basic capacitor group of the target transformer to obtain the required capacitance data of the target transformer specifically includes: according to the winding distribution form of the target transformer, combining the capacitance value of the outermost winding of the target transformer to the oil tank, the capacitance value of the innermost winding to the iron core, and the capacitance value between two adjacent windings to obtain the single-phase capacitance value of each winding of the target transformer to the ground and the single-phase capacitance value between windings, thereby obtaining the capacitance data of the target transformer. Specifically:

[0152] In this embodiment, when the target transformer is classified as a two-winding transformer according to the winding distribution form and the iron core, the low-voltage winding, the high-voltage winding (which can carry a high-voltage regulating winding), and the oil tank are arranged in sequence along the radial direction, the capacitance values in the second basic capacitor group are set respectively as:

[0153] The capacitance value C1 (unit: pF, the same below) of the high-voltage winding to the oil tank, the capacitance value C2 (pF) of the low-voltage winding to the iron core, and the capacitance value C3 (pF) of the high-voltage winding to the low-voltage winding;

[0154] Then combining the capacitance values in the second basic capacitor group of the target transformer to obtain the required capacitance data of the target transformer specifically includes:

[0155] According to C 高地 = C1 + C3 to obtain the single-phase capacitance C of the high-voltage winding to the ground 高地 ;

[0156] According to C 低地 = C2 + C3 to obtain the single-phase capacitance C of the low-voltage winding to the ground 低地 ;

[0157] According to C 高低 = C3 to obtain the single-phase capacitance C of the high-voltage winding to the low-voltage winding 高低 ;

[0158] According to C 高低地 = C1 + C2 to obtain the single-phase capacitance C of the high-voltage winding and the low-voltage winding to the ground 高低地 .

[0159] In this embodiment, the target transformer is classified as a three-winding transformer according to the winding distribution form. When the iron core, low-voltage winding, medium-voltage winding, high-voltage winding (which can be with a high-voltage regulating winding), and the oil tank are arranged radially in sequence, the capacitance values in the second basic capacitance group are set respectively as follows:

[0160] The capacitance value C1 (pF) of the high-voltage winding to the oil tank, the capacitance value C2 (pF) of the low-voltage winding to the iron core, the capacitance value C3 (pF) of the medium-voltage winding to the low-voltage winding, the capacitance value C4 (pF) of the high-voltage winding to the medium-voltage winding

[0161] Then, the capacitance values in the second basic capacitance group of the target transformer are combined to obtain the capacitance data of the required target transformer, specifically including:

[0162] According to C 高地 = C1 + C4 to obtain the single-phase capacitance C of the high-voltage winding to the ground 高地 ;

[0163] According to C 中地 = C3 + C4 to obtain the single-phase capacitance C of the medium-voltage winding to the ground 中地 ;

[0164] According to C 低地 = C2 + C3 to obtain the single-phase capacitance C of the low-voltage winding to the ground 低地 ;

[0165] According to C 高中地 = C1 + C3 to obtain the single-phase capacitance C of the high-voltage winding and the medium-voltage winding to the ground 高中地 ;

[0166] According to C 高中低地 = C1 + C2 to obtain the single-phase capacitance C of the high-voltage winding, the medium-voltage winding, and the low-voltage winding to the ground 高中低地 ;

[0167] According to C 高中 = C4 to obtain the single-phase capacitance C of the high-voltage winding to the medium-voltage winding 高中 ;

[0168] According to C 中低 = C3 to obtain the single-phase capacitance C of the medium-voltage winding to the low-voltage winding 中低 ;

[0169] According to C 高低 = (C3 × C4) / (C3 + C4) to obtain the single-phase capacitance C of the high-voltage winding to the low-voltage winding 高低 .

[0170] In this embodiment, the target transformer is classified as an autotransformer according to the winding distribution form. When arranging the iron core, low-voltage winding, medium-voltage winding, high-voltage winding (which can be equipped with a high-tuning winding), and the oil tank in sequence along the radial direction, the capacitance values in the second basic capacitor group are set respectively as follows:

[0171] The capacitance value C1 (pF) of the high-voltage winding to the oil tank, the capacitance value C2 (pF) of the low-voltage winding to the iron core, and the capacitance value C3 (pF) of the medium-voltage winding to the low-voltage winding.

[0172] Then, the capacitance values in the second basic capacitor group of the target transformer are combined to obtain the required capacitance data of the target transformer, specifically including:

[0173] According to C 高中地 = C1 + C3 to obtain the single-phase capacitance C 高中地 of the high-voltage winding and the medium-voltage winding to the ground;

[0174] According to C 低地 = C2 + C3 to obtain the single-phase capacitance C 低地 of the low-voltage winding to the ground;

[0175] According to C 高中低 = C3 to obtain the single-phase capacitance C 高中低 of the high-voltage winding and the medium-voltage winding to the low-voltage winding;

[0176] According to C 高中低地 = C1 + C2 to obtain the single-phase capacitance C 高中低地 of the high-voltage winding, the medium-voltage winding, and the low-voltage winding to the ground.

[0177] In this embodiment, the target transformer is classified as a split transformer according to the winding distribution form. When arranging the iron core, the first low-voltage winding, the second low-voltage winding, the high-voltage winding (which can be equipped with a high-tuning winding), and the oil tank in sequence along the radial direction (or the distribution form is iron core, (the first low-voltage winding + the second low-voltage winding), high-voltage winding (which can be equipped with a high-tuning winding), oil tank), the capacitance values in the second basic capacitor group are set respectively as follows:

[0178] The capacitance value C1 (pF) of the high-voltage winding to the oil tank, the capacitance value C2 (pF) of the first low-voltage winding to the iron core, and the capacitance value C3 (pF) of the high-voltage winding to the first low-voltage winding.

[0179] Then, the capacitance values in the second basic capacitor group of the target transformer are combined to obtain the required capacitance data of the target transformer, specifically including:

[0180] According to C 高地 = C1 + 2×C3 to obtain the single-phase capacitance C 高地 of the high-voltage winding to the ground;

[0181] According to C 低1地 = C2 + C3 to obtain the single-phase capacitance C of the first low-voltage winding to the ground 低1地 ;

[0182] According to C 低2地 = C2 + C3 to obtain the single-phase capacitance C of the second low-voltage winding to the ground 低2地 ;

[0183] According to C 高低1地 = C1 + C2 + C3 to obtain the single-phase capacitance C of the high-voltage winding and the first low-voltage winding to the ground 高低1地 ;

[0184] According to C 高低1低2地 = C1 + 2 * C2 to obtain the single-phase capacitance C of the high-voltage winding, the first low-voltage winding and the second low-voltage winding to the ground 高低1低2地 ;

[0185] According to C 高低1 = C3 to obtain the single-phase capacitance C of the high-voltage winding to the first low-voltage winding 高低1 ;

[0186] According to C 高低2 = C3 to obtain the single-phase capacitance C of the high-voltage winding to the second low-voltage winding 高低 2

[0187] In this embodiment, there are various actual transformer winding combination methods to which this method can be applied. The capacitance calculations for other different combination methods are also applicable to the above logical calculation method after obtaining the basic capacitance group. The high-voltage winding, etc. in the above content are relative concepts with respect to the medium-voltage winding and the low-voltage winding, which are conventional description methods in the transformer field and will not be specifically elaborated here

[0188] In summary, this embodiment provides a transformer capacitance calculation method, belonging to the technical field of transformers, which can be used for the capacitance calculation schemes of the windings to the ground and between the windings of a three-phase integrated oil-immersed transformer, so as to solve the problems of low capacitance calculation efficiency and low result accuracy for the windings to the ground and between the windings of the current three-phase integrated oil-immersed transformer. It includes the calculation method of the single-winding capacitance value of the transformer to the ground and the calculation method of the capacitance value between different windings. Based on the measured capacitance data of the transformer product, transformers with different winding distribution forms (or winding combination methods), different capacities, and different voltage levels are classified, and the capacitance values of each decomposed part are obtained by using the functional relationships of the winding combination method, capacity, and voltage, and then combined into the final capacitance of the windings to the ground and between the windings

[0189] This method can replace complex transformer capacitance simulation calculations, quickly calculate transformer capacitance values that are highly consistent with measured values, greatly simplify the calculation of transformer capacitance, save time, and improve the accuracy of calculation results. It is applicable to oil-immersed transformers such as three-phase integrated high-voltage station service transformers, generator transformers, autotransformers, and split transformers with voltages ranging from 20 kV to 750 kV, and has the characteristics of a wide application range, simple calculation process, and high result accuracy.

[0190] This method can be specifically implemented according to the technology in the above method content to calculate the capacitance values of transformers with various winding distribution forms. In Example 2, the capacitance calculation of a three-winding transformer with a common radial arrangement of core - low-voltage winding - medium-voltage winding - high-voltage winding - high-tension winding - oil tank is used as an example for further illustration. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0191] Example 2

[0192] This example provides a method for calculating transformer capacitance. Refer to Figure 1 as shown in Figure 1 which is a schematic flow diagram of this method for calculating transformer capacitance, including:

[0193] Step 11: Collect capacitance test data of produced transformer products and classify them according to transformer capacity, winding distribution form, and winding voltage level;

[0194] The winding distribution form of this example is shown in Figure 2 as Figure 2 a combined form diagram of a three-winding transformer with a radial arrangement of core - low-voltage winding - medium-voltage winding - high-voltage winding - high-tension winding - oil tank;

[0195] The test data of collected similar transformer products can obtain the capacitance of the high-voltage winding to the ground, the capacitance of the medium-voltage winding to the ground, the capacitance of the low-voltage winding to the ground, the capacitance of the high-voltage winding and the medium-voltage winding to the ground, the capacitance of the high-voltage winding, the medium-voltage winding, and the low-voltage winding to the ground, the capacitance of the high-voltage winding to the low-voltage winding, the capacitance of the high-voltage winding to the medium-voltage winding, and the capacitance of the medium-voltage winding to the low-voltage winding;

[0196] Step 12: Decompose the actual capacitance values of each transformer winding according to the test data to obtain the capacitance values of each independent part, that is, decompose the test data in combination with the transformer winding distribution form or the coil combination form to obtain the capacitance values of each independent part;

[0197] According to this example Figure 2For the shown structural form, obtain the capacitance values C1 between the high-voltage winding and the high-voltage regulating winding and the oil tank in the same type of transformer products, the capacitance value C2 between the low-voltage winding and the iron core, the capacitance value C3 between the medium-voltage winding and the low-voltage winding, and the capacitance value C4 between the high-voltage winding and the high-voltage regulating winding and the medium-voltage winding;

[0198] Step 13: According to the capacitance values of each independent part, summarize to obtain the capacitance calculation formulas for each independent part;

[0199] That is, summarize the capacitance of the outer winding of the transformer to the oil tank according to the decomposed capacitance of the outer winding of the transformer to the oil tank, and summarize the functional relationship between the capacitance of the outer winding of the transformer to the oil tank, the winding distribution form, capacity, and voltage level of the transformer, so as to obtain the capacitance calculation formula of the outer winding of the transformer to the oil tank; according to the structural form shown in this embodiment Figure 2 shown:

[0200] The outer winding of the transformer is a high-voltage winding with a high-voltage regulating winding, the corresponding capacity of the transformer is S (kVA), and the capacitance C1 (pF) between the high-voltage winding and the high-voltage regulating winding and the oil tank is:

[0201] ① When the voltage level of the high-voltage winding of the transformer is 35 kV and below, C1 = 0.0082S + 544;

[0202] ② When the voltage level of the high-voltage winding of the transformer is 110 kV, C1 = 0.0038S + 1063;

[0203] ③ When the voltage level of the high-voltage winding of the transformer is 220 kV, C1 = 0.0033S + 1336;

[0204] ④ When the voltage level of the high-voltage winding of the transformer is 330 kV, C1 = 0.003S + 1496;

[0205] ⑤ When the voltage level of the high-voltage winding of the transformer is 500 kV, C1 = 0.0033S + 1806;

[0206] ⑥ When the voltage level of the high-voltage winding of the transformer is 750 kV, C1 = 0.0013S + 3658;

[0207] The capacitance value C2 between the low-voltage winding and the iron core is calculated as C2 = 0.0556εH / ln(R2 / R1), where ε is the relative dielectric constant of the main air duct material between the low-voltage winding and the iron core, H is the height of the low-voltage winding, R1 is the radius of the iron core, and R2 is the inner radius of the low-voltage winding;

[0208] The capacitance value C3 between the medium-voltage winding and the low-voltage winding is calculated as C3 = 0.0556ξL / ln(R4 / R3), where ξ is the relative dielectric constant of the main air duct material between the medium-voltage winding and the low-voltage winding, L is the average height of the medium-voltage winding and the low-voltage winding, R3 is the outer radius of the low-voltage winding, and R4 is the inner radius of the medium-voltage winding;

[0209] The capacitance value C4 between the high-voltage winding and the high-voltage regulating winding and the medium-voltage winding is calculated as C4 = 0.0556ξL / ln(R6 / R5), where ξ is the relative permittivity of the main air duct material between the high-voltage winding and the medium-voltage winding, L is the average height of the high-voltage winding and the medium-voltage winding, R5 is the outer radius of the medium-voltage winding, and R6 is the inner radius of the high-voltage winding;

[0210] Step 14: According to the capacitance calculation formulas established in Step 13, calculate the capacitances of each independent part of the newly designed transformer, that is, the target transformer, respectively. According to the structural form shown in this embodiment Figure 2 and the technical parameters of the target transformer, obtain the capacitance value C1 between the high-voltage winding and the high-voltage regulating winding and the oil tank, the capacitance value C2 between the low-voltage winding and the iron core, the capacitance value C3 between the medium-voltage winding and the low-voltage winding, and the capacitance value C4 between the high-voltage winding and the high-voltage regulating winding and the medium-voltage winding;

[0211] Step 15: According to the capacitance values of each independent part established in Step 14, combine the capacitances of each independent part. According to the structural form shown in this embodiment Figure 2 then the capacitance values of each winding to the ground and the capacitance values between windings are:

[0212] ① Capacitance of the high-voltage winding to the ground: C 高地 = C1 + C4;

[0213] ② Capacitance of the medium-voltage winding to the ground: C 中地 = C3 + C4;

[0214] ③ Capacitance of the low-voltage winding to the ground: C 低地 = C2 + C3;

[0215] ④ Capacitance of the high-voltage winding and the medium-voltage winding to the ground: C 高中地 = C1 + C3;

[0216] ⑤ Capacitance of the high-voltage winding, the medium-voltage winding and the low-voltage winding to the ground: C 高中低地 = C1 + C2;

[0217] ⑥ Capacitance of the high-voltage winding to the medium-voltage winding: C 高中 = C4;

[0218] ⑦ Capacitance of the medium-voltage winding to the low-voltage winding: C 中低 = C3;

[0219] ⑧ Capacitance of the high-voltage winding to the low-voltage winding: C 高低 = (C3 × C4) / (C3 + C4);

[0220] Thus, the transformer capacitance required by the user can be obtained in the initial stage of the transformer scheme design.

[0221] Example 3

[0222] A method for constructing a power generation system according to this embodiment includes the following steps: calculating the capacitance data of the target transformer by using the transformer capacitance calculation method in Embodiment 1 or 2;

[0223] selecting the matching devices in the power generation system according to the capacitance data of the target transformer, so as to obtain the construction plan of the power generation system;

[0224] constructing the power generation system according to the construction plan of the power generation system.

[0225] Example 4

[0226] The transformer capacitance calculation system according to this embodiment can implement the transformer capacitance calculation methods in Embodiments 1 and 2. The system includes: a fitting module for obtaining the correspondence between the first basic capacitance group of the transformer product and the first technical parameters of the transformer product; a first calculation module electrically connected to the fitting module for obtaining the second basic capacitance group of the target transformer according to the second technical parameters of the target transformer and the correspondence; a second calculation module electrically connected to the first calculation module for combining the capacitance values in the second basic capacitance group of the target transformer to obtain the required capacitance data of the target transformer.

[0227] The embodiments of the present invention have been described above in conjunction with the accompanying drawings. However, the present invention is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not restrictive. Under the inspiration of the present invention, those of ordinary skill in the art can also make many forms without departing from the purpose of the present invention and the scope protected by the claims, and all of them belong to the protection scope of the present invention.

Claims

1. A method for calculating transformer capacitance, characterized in that: The following steps are involved: Acquire a correspondence between a first basic capacitor group of a transformer product and a first technical parameter of the transformer product; Acquire a second basic capacitor group of the target transformer according to the second technical parameter of the target transformer and the corresponding relationship; The capacitance values ​​in the second basic capacitance group of the target transformer are combined to obtain the required capacitance data of the target transformer.

2. The transformer capacitance calculation method according to claim 1, characterized in that: The corresponding relationship includes: The calculation formula for the capacitance value of the outermost winding of the transformer to the transformer oil tank, the calculation formula for the capacitance value of the innermost winding of the transformer to the transformer core, and the calculation formula for the capacitance value between two adjacent windings of the transformer.

3. The transformer capacitance calculation method according to claim 2, characterized in that: The calculation formula for the capacitance value of the outermost winding of the transformer to the transformer tank is: C1=α·S+β Among them, C1 is the capacitance value of the outermost winding of the transformer to the transformer oil tank, S is the transformer capacity, α and β are coefficients obtained by the change law of each capacitance value in the first basic capacitance group with the first technical parameter, and are both related to the winding distribution form of the transformer and the voltage level of the outermost winding.

4. The transformer capacitance calculation method according to claim 3, characterized in that: Before obtaining the correspondence between the first basic capacitance group of the transformer product and the first technical parameter of the transformer product, the method further comprises the following steps: Obtain the capacitance test data of transformer products, and classify the capacitance test data of transformer products according to the winding distribution form and winding voltage level; The calculation formula of the capacitance value of the outermost winding of the transformer to the transformer oil tank includes the calculation formula of each winding voltage level in the following types of winding distribution forms: ① When the outermost winding of the transformer is a high-voltage winding and does not have a voltage regulating winding: When the voltage level of the transformer high-voltage winding is 35kV or below, C1=0.0013S+708; When the voltage level of the transformer high-voltage winding is 110kV, C1=0.0076S+779; When the voltage level of the transformer high-voltage winding is 220kV, C1=0.0023S+1078; When the voltage level of the transformer high-voltage winding is 330kV, C1=0.0022S+1054; When the voltage level of the transformer high-voltage winding is 500kV, C1=0.002S+1354; When the voltage level of the transformer high-voltage winding is 750kV, C1=0.0009S+2710; ② When the outermost winding of the transformer is a high-voltage winding with a high-regulation winding: When the voltage level of the transformer high-voltage winding is 35kV or below, C1=0.0082S+544; When the voltage level of the transformer high-voltage winding is 110kV, C1=0.0038S+1063; When the voltage level of the transformer high-voltage winding is 220kV, C1=0.0033S+1336; When the voltage level of the transformer high-voltage winding is 330kV, C1=0.003S+1496; When the voltage level of the transformer high-voltage winding is 500kV, C1=0.0033S+1806; When the voltage level of the transformer high-voltage winding is 750kV, C1=0.0013S+3658; ③ When the outermost winding of the transformer is a high-voltage winding with a high-regulation winding and a medium-regulation winding: When the voltage level of the transformer high-voltage winding is 35kV or below, C1=0.0088S+490; When the voltage level of the transformer high-voltage winding is 110kV, C1=0.0041S+954; When the voltage level of the transformer high-voltage winding is 220kV, C1=0.0036S+1193; When the voltage level of the transformer high-voltage winding is 330kV, C1=0.0032S+1348; When the voltage level of the transformer high-voltage winding is 500kV, C1=0.0036S+1627; When the voltage level of the transformer high-voltage winding is 750kV, C1=0.0014S+3295; ④ When the outermost winding of the transformer is a low-voltage winding: When the voltage level of the transformer low-voltage winding is 35kV or below, C1=0.0051S+117.

5. The transformer capacitance calculation method according to claim 2, characterized in that: The calculation formula for the capacitance value of the innermost winding of the transformer to the transformer core is: C2=γ·εH / ln(R2 / R1) Among them, C2 is the capacitance value of the innermost winding of the transformer to the transformer core, γ is a coefficient obtained by the variation law of each capacitance value in the first basic capacitance group with the first technical parameter, and is related to the winding distribution form of the transformer, ε is the relative dielectric constant of the main air channel material between the innermost winding and the core, H is the height of the innermost winding, R1 is the core radius, and R2 is the inner radius of the innermost winding.

6. The transformer capacitance calculation method according to claim 2, characterized in that: The calculation formula for the capacitance value between two adjacent windings of the transformer is: Cn=τ·ξL / ln(R4 / R3) Among them, Cn is the capacitance value between two adjacent windings of the transformer, τ is a coefficient obtained by the variation law of each capacitance value in the first basic capacitance group with the first technical parameter, and is related to the winding distribution form of the transformer, ξ is the relative dielectric constant of the main air channel material between the two adjacent windings, L is the average height of the two adjacent windings, R3 is the outer radius of the inner winding of the two adjacent windings, and R4 is the inner radius of the outer winding of the two adjacent windings.

7. The transformer capacitance calculation method according to claim 2, characterized in that: The second basic capacitor group of the target transformer includes: The capacitance value of the outermost winding of the target transformer to the oil tank, the capacitance value of the innermost winding to the iron core, and the capacitance value between two adjacent windings; The step of combining the capacitance values ​​in the second basic capacitance group of the target transformer to obtain the required capacitance data of the target transformer specifically includes: According to the winding distribution of the target transformer, the capacitance value of the outermost winding of the target transformer to the oil tank, the capacitance value of the innermost winding to the iron core, and the capacitance value between two adjacent windings are combined to obtain the single-phase capacitance value of each winding of the target transformer to the ground and the single-phase capacitance value between windings, thereby obtaining the capacitance data of the target transformer.

8. The transformer capacitance calculation method according to claim 7, characterized in that: The target transformer is classified as a double-winding transformer according to the winding distribution form, and when the iron core, low-voltage winding, high-voltage winding and oil tank are arranged radially in sequence, the capacitance values ​​in the second basic capacitor group are set as follows: The capacitance value of the high voltage winding to the oil tank is C1, the capacitance value of the low voltage winding to the iron core is C2, and the capacitance value of the high voltage winding to the low voltage winding is C3; Then, the step of combining the capacitance values ​​in the second basic capacitance group of the target transformer to obtain the required capacitance data of the target transformer specifically includes: According to C 高地 =C1+C3 to obtain the single-phase capacitance C of the high-voltage winding to ground 高地 ; According to C 低地 =C2+C3 to get the single-phase capacitance C of the low voltage winding to ground 低地 ; According to C 高低 = C3 to obtain the single-phase capacitance C of the high voltage winding to the low voltage winding 高低 ; According to C 高低地 = C1 + C2 to obtain the single-phase capacitance C of the high-voltage winding and the low-voltage winding to the ground 高低地 .

9. The transformer capacitance calculation method according to claim 7, characterized in that: When the target transformer is classified as a three-winding transformer according to the winding distribution form, and the iron core, low-voltage winding, medium-voltage winding, high-voltage winding and oil tank are arranged radially in sequence, the capacitance values ​​in the second basic capacitor group are set as follows: The capacitance value of the high voltage winding to the oil tank is C1, the capacitance value of the low voltage winding to the iron core is C2, the capacitance value of the medium voltage winding to the low voltage winding is C3, and the capacitance value of the high voltage winding to the medium voltage winding is C4. Then, the step of combining the capacitance values ​​in the second basic capacitance group of the target transformer to obtain the required capacitance data of the target transformer specifically includes: According to C 高地 =C1+C4 to obtain the single-phase capacitance C of the high-voltage winding to ground 高地 ; According to C 中地 = C3 + C4 to obtain the single-phase capacitance C of the medium voltage winding to ground 中地 ; According to C 低地 =C2+C3 to get the single-phase capacitance C of the low voltage winding to ground 低地 ; According to C 高中地 = C1 + C3 to obtain the single-phase capacitance C of the high-voltage winding and the medium-voltage winding to the ground 高中地 ; According to C 高中低地 = C1 + C2 to obtain the single-phase capacitance C of the high-voltage winding, medium-voltage winding and low-voltage winding to ground 高中低地 ; According to C 高中 = C4 to obtain the single-phase capacitance C of the high voltage winding to the medium voltage winding 高中 ; According to C 中低 = C3 to obtain the single-phase capacitance C of the medium voltage winding to the low voltage winding 中低 ; According to C 高低 =(C3×C4) / (C3+C4) to obtain the single-phase capacitance C of the high-voltage winding to the low-voltage winding 高低 .

10. The transformer capacitance calculation method according to claim 7, characterized in that: When the target transformer is classified as an autotransformer according to the winding distribution form, and the iron core, low voltage winding, medium voltage winding, high voltage winding and oil tank are arranged radially in sequence, the capacitance values ​​in the second basic capacitor group are set as follows: The capacitance value of the high voltage winding to the oil tank is C1, the capacitance value of the low voltage winding to the iron core is C2, and the capacitance value of the medium voltage winding to the low voltage winding is C3. Then, the step of combining the capacitance values ​​in the second basic capacitance group of the target transformer to obtain the required capacitance data of the target transformer specifically includes: According to C 高中地 = C1 + C3 to obtain the single-phase capacitance C of the high-voltage winding and the medium-voltage winding to the ground 高中地 ; According to C 低地 =C2+C3 to get the single-phase capacitance C of the low voltage winding to ground 低地 ; According to C 高中低 = C3 to obtain the single-phase capacitance C of the high-voltage winding and the medium-voltage winding to the low-voltage winding 高中低 ; According to C 高中低地 = C1 + C2 to obtain the single-phase capacitance C of the high-voltage winding, medium-voltage winding and low-voltage winding to ground 高中低地 .

11. The transformer capacitance calculation method according to claim 7, characterized in that: The target transformer is classified as a split transformer according to the winding distribution form, and when the iron core, the first low-voltage winding, the second low-voltage winding, the high-voltage winding and the oil tank are arranged radially in sequence, the capacitance values ​​in the second basic capacitor group are set as follows: The capacitance value of the high voltage winding to the oil tank is C1, the capacitance value of the first low voltage winding to the iron core is C2, and the capacitance value of the high voltage winding to the first low voltage winding is C3. Then, the step of combining the capacitance values ​​in the second basic capacitance group of the target transformer to obtain the required capacitance data of the target transformer specifically includes: According to C 高地 =C1+2×C3 to obtain the single-phase capacitance C of the high-voltage winding to ground 高地 ; According to C 低1地 = C2 + C3 to obtain the single-phase capacitance C of the first low-voltage winding to ground 低1地 ; According to C 低2地 =C2+C3 to obtain the single-phase capacitance C of the second low-voltage winding to ground 低2地 ; According to C 高低1地 = C1 + C2 + C3 to obtain the single-phase capacitance C of the high-voltage winding and the first low-voltage winding to ground 高低1地 ; According to C 高低1低2地 = C1 + 2 * C2 to obtain the single-phase capacitance C of the high-voltage winding, the first low-voltage winding and the second low-voltage winding to ground 高低1低2地 ; According to C 高低1 = C3 to obtain the single-phase capacitance C of the high voltage winding to the first low voltage winding 高低1 ; According to C 高低2 = C3 to obtain the single-phase capacitance C of the high voltage winding to the second low voltage winding 高低 2.

12. A method for constructing a power generation system, characterized in that: The following steps are involved: The capacitance data of the target transformer is calculated by using the transformer capacitance calculation method described in any one of claims 1 to 11; According to the capacitance data of the target transformer, the matching equipment in the power generation system is selected to obtain the construction plan of the power generation system; The power generation system is constructed according to the construction plan of the power generation system.

13. A transformer capacitance calculation system, characterized in that: The method for calculating transformer capacitance according to any one of claims 1 to 11 can be implemented, and the system comprises: A fitting module is used to obtain a corresponding relationship between a first basic capacitor group of a transformer product and a first technical parameter of the transformer product. A first calculation module is electrically connected to the fitting module and is used to obtain a second basic capacitance group of the target transformer according to the second technical parameter of the target transformer and the corresponding relationship. The second calculation module is electrically connected to the first calculation module, and is used to combine the capacitance values ​​in the second basic capacitance group of the target transformer to obtain the required capacitance data of the target transformer.

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