Method and system for determining the structure of a transient measurement assembly of a pipe mother direct connection transformer

Abstract

The application provides a pipe bus direct connection type transformer transient measurement assembly structure determination method and system, and relates to the high-voltage electrical technical field. First, the ideal voltage division ratio of the pipe bus direct connection type transformer is determined; then, the low-voltage arm capacitor and initial assembly parameters of the transient measurement structure are determined based on the ideal voltage division ratio. Subsequently, whether the current transient measurement structure meets the range design is judged according to the high-voltage arm capacitor of the transient measurement structure; if not, the shielding cover structure is added, the updated assembly parameters are obtained by adjusting the height parameters of the shielding cover, and the high-voltage arm capacitor of the transient measurement structure is updated and calculated based on the fixed structure parameters and the updated assembly parameters, until the range design is met, and the final assembly parameters are obtained. Based on this, the application can be compatible with different specifications of the pipe bus direct connection type power transformer.

Description

Technical Field

[0001] This invention relates to the field of high-voltage electrical technology, and more specifically, to a method and system for determining the transient measurement assembly structure of a direct-connected busbar transformer. Background Technology

[0002] As a crucial clean energy facility, the operational reliability of large-scale hydropower stations directly impacts grid security. To achieve compact design, modern large-scale hydropower stations generally employ a direct-connection busbar structure. This means the high-voltage side of the power transformer is directly connected via a high-voltage combined electrical unit busbar filled with sulfur hexafluoride (SF6) insulating gas, while the low-voltage side is connected to the generator outlet via an air-insulated enclosed busbar. This structural design effectively reduces the land area required, but it also presents new challenges for monitoring the transformer's operational status.

[0003] Transient voltage measurement at transformer terminals is a crucial method for assessing their insulation condition and operational characteristics. Currently, voltage transformers are widely used in power systems for voltage measurement, but their initial design was for accurate measurement of 50Hz power frequency voltage, resulting in a limited frequency response range. When measuring high-frequency transient voltages above 100kHz, traditional voltage transformers exhibit significant bandwidth limitations, failing to meet the bandwidth requirements for transient voltage measurement. Furthermore, due to the differences in the high- and low-voltage side busbar structures of each transformer, including variations in diameter, insulation medium, and arrangement, existing hand-held capacitive voltage dividers cannot be directly universally applied and must be customized based on specific busbar structure parameters. This non-standard characteristic makes determining the structural dimensions of transient voltage sensors particularly critical, requiring specialized design for the specific structural parameters of different transformers to obtain a suitable voltage division ratio and range.

[0004] Therefore, there is an urgent need for a general and definitive solution for the assembly structure of transient measurement sensors suitable for direct-connected transformers, which can be compatible with different specifications of direct-connected power transformers. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a method and system for determining the transient measurement assembly structure of a direct-connected busbar transformer, which is compatible with direct-connected busbar power transformers of different specifications, and thus provides a method for determining a transient voltage measurement scheme for transformer ports that meets the range requirements.

[0006] To achieve the above objectives, the technical solutions adopted in the embodiments of the present invention are as follows:

[0007] In a first aspect, the present invention provides a method for determining the transient measurement assembly structure of a direct-connected transformer, applied to a transient measurement structure. The transient measurement structure is assembled at the handhole of the direct-connected transformer. The transient measurement structure includes an induction electrode and an insulating film. The direct-connected transformer includes a busbar. The method for determining the transient measurement assembly structure of the direct-connected transformer includes:

[0008] Obtain the rated parameters and fixed structural parameters of the direct-connected transformer with a tube busbar; wherein, the rated parameters include the rated voltage and the maximum voltage measurement range; the fixed structural parameters include at least the outer radius of the conductive rod of the tube busbar, the length of the conductive rod, the inner radius of the metal shell, the width of the hand hole, the height of the hand hole, and the inner chamfer radius of the hand hole;

[0009] Determine the ideal voltage divider ratio based on the rated voltage and the maximum voltage measurement range;

[0010] The low-voltage arm capacitance of the transient measurement structure is determined based on the ideal voltage division ratio, and the initial assembly parameters of the transient measurement structure are obtained; the low-voltage arm capacitance characterizes the self-capacitance of the sensing electrode to ground; the initial assembly parameters include at least the radius and thickness of the sensing electrode, and the material and thickness of the insulating film;

[0011] The high-voltage arm capacitance of the transient measurement structure is determined based on the initial assembly parameters and fixed structural parameters; the high-voltage arm capacitance is used to characterize the mutual capacitance between the induction electrode and the conductive rod in the tube.

[0012] The ideal high-voltage arm capacitance is calculated based on the ideal voltage division ratio and the low-voltage arm capacitance; wherein, the formula for calculating the ideal high-voltage arm capacitance satisfies:

[0013] ;

[0014] in, The ideal high-voltage arm capacitance value; Ideal partial pressure ratio; The capacitance value is for the low-voltage arm.

[0015] Determine whether the high-voltage arm capacitance of the transient measurement structure is less than or equal to the ideal high-voltage arm capacitance;

[0016] If it is less than or equal to, then the current transient measurement structure is determined to meet the range design, and the initial assembly parameters of the current transient measurement structure are used as the final assembly parameters.

[0017] If the requirements are not met, a shielding structure is added. The updated assembly parameters are obtained by adjusting the height parameter of the shielding. The high-voltage arm capacitance of the transient measurement structure is updated and calculated based on the fixed structural parameters and the updated assembly parameters. The process of determining whether the current transient measurement structure meets the range design is then returned based on the high-voltage arm capacitance, low-voltage arm capacitance, and ideal voltage division ratio of the current transient measurement structure.

[0018] Optionally, the steps for determining the high-voltage arm capacitance of the transient measurement structure based on initial assembly parameters and fixed structural parameters include:

[0019] An initial geometric assembly model is constructed based on the radius and thickness of the induction electrode, the material and thickness of the insulating film, the outer radius of the conductive rod of the tube, the length of the conductive rod, the inner radius of the metal shell, the width of the hand hole, the height of the hand hole, and the inner chamfer radius of the hand hole.

[0020] Determine the electrostatic field domain corresponding to the initial geometric assembly model;

[0021] The high-voltage arm capacitance of the transient measurement structure is determined using the finite element method based on the electrostatic field corresponding to the initial geometric assembly model.

[0022] Optionally, the steps for determining the high-voltage arm capacitance of the transient measurement structure using the finite element method based on the electrostatic field corresponding to the initial geometric assembly model include:

[0023] The electric field energy density corresponding to the initial geometric assembly model is determined based on the electrostatic field domain corresponding to the initial geometric assembly model.

[0024] The high-voltage arm capacitance of the transient measurement structure is determined using the finite element method based on the electric field energy density corresponding to the initial geometric assembly model.

[0025] Optionally, the formula for calculating the high-voltage arm capacitance of the transient measurement structure based on the electric field energy density corresponding to the initial geometric assembly model using the finite element method is expressed as follows:

[0026] ;

[0027] in, The high-voltage arm capacitor of the transient measurement structure; The terminal voltage of the conductive rod in the tube is denoted as . This is the terminal voltage of the sensing electrode; This represents the electric field energy density corresponding to the initial geometric assembly model.

[0028] Optionally, the calculation formula for the initial assembly parameters of the transient measurement structure is expressed as:

[0029] ;

[0030] in, The low-voltage arm capacitor is for the transient measurement structure; The vacuum permittivity, The relative permittivity of the insulating film. The thickness of the insulating film. Let be the radius of the sensing electrode.

[0031] Optionally, the step of updating the calculation of the high-voltage arm capacitance of the transient measurement structure based on fixed structural parameters and updated assembly parameters includes:

[0032] An optimized geometric assembly model is constructed based on the height parameters of the shielding cover and the outer radius, length, inner radius, handhole width, handhole height, and inner chamfer radius of the conductive rod of the main tube.

[0033] Establish the electrostatic field domain of the optimized geometric assembly model;

[0034] The high-voltage arm capacitance of the transient measurement structure was calculated using the finite element method based on the electrostatic field of the optimized geometric assembly model.

[0035] Optionally, the steps of adding a shielding structure and obtaining updated assembly parameters by adjusting the height parameter of the shielding include:

[0036] The height of the shield is added to the initial assembly parameters, and the height is used as a global parameter. The height increases from zero in a preset step size until the current transient measurement structure meets the range design.

[0037] Secondly, the present invention also provides a transient measurement assembly structure determination system for a direct-connected transformer, applied to a transient measurement structure. The transient measurement structure is assembled at the handhole of the direct-connected transformer. The transient measurement structure includes an induction electrode and an insulating film. The direct-connected transformer includes a busbar, comprising:

[0038] The ideal voltage division ratio determination module is used to obtain the rated parameters and fixed structural parameters of the direct-connected transformer. The rated parameters include the rated voltage and the maximum voltage measurement range. The fixed structural parameters include at least the outer radius of the conductor rod, the length of the conductor rod, the inner radius of the metal shell, the width of the handhole, the height of the handhole, and the inner chamfer radius of the handhole. The module determines the ideal voltage division ratio based on the rated voltage and the maximum voltage measurement range.

[0039] The low-voltage arm capacitance determination module is used to determine the low-voltage arm capacitance of the transient measurement structure based on the ideal voltage division ratio and obtain the initial assembly parameters of the transient measurement structure; the low-voltage arm capacitance characterizes the self-capacitance of the sensing electrode to ground; the initial assembly parameters include at least the radius and thickness of the sensing electrode, and the material and thickness of the insulating film;

[0040] The high-voltage arm capacitance determination module is used to determine the high-voltage arm capacitance of the transient measurement structure based on the initial assembly parameters and fixed structural parameters; the high-voltage arm capacitance is used to characterize the mutual capacitance between the induction electrode and the conductive rod in the tube nut.

[0041] The range determination module is used to calculate the ideal high-voltage arm capacitance based on the ideal voltage divider ratio and the low-voltage arm capacitance; wherein the calculation formula for the ideal high-voltage arm capacitance satisfies:

[0042] ;

[0043] in, The ideal high-voltage arm capacitance value; Ideal partial pressure ratio; The low-voltage arm capacitance value is determined; and it is determined whether the high-voltage arm capacitance of the transient measurement structure is less than or equal to the ideal high-voltage arm capacitance.

[0044] The range determination module is also used to determine if the current transient measurement structure meets the range design if the range is less than or equal to the specified range, and then use the initial assembly parameters of the current transient measurement structure as the final assembly parameters.

[0045] The range determination module is also used to determine whether the current transient measurement structure meets the range design. After determining that the current transient measurement structure does not meet the range design, a shielding structure is added, and the updated assembly parameters are obtained by adjusting the height parameter of the shielding structure. Based on the fixed structure parameters and the updated assembly parameters, the high voltage arm capacitance of the transient measurement structure is updated and calculated. The module then returns the steps of determining whether the current transient measurement structure meets the range design based on the high voltage arm capacitance, low voltage arm capacitance and ideal voltage division ratio of the current transient measurement structure.

[0046] The present invention provides a method and system for determining the transient measurement assembly structure of a direct-connected transformer, which has the following beneficial effects:

[0047] This application obtains the fixed structural parameters and the rated voltage and maximum voltage measurement range of the direct-connected busbar transformer; then, it determines the ideal voltage division ratio based on the rated voltage and maximum voltage measurement range; simultaneously, it determines the low-voltage arm capacitance of the transient measurement structure based on the ideal voltage division ratio, and obtains the initial assembly parameters of the transient measurement structure. Subsequently, it determines the high-voltage arm capacitance of the transient measurement structure based on the initial assembly parameters and the fixed structural parameters; then, it judges whether the current transient measurement structure meets the range design based on the low-voltage arm capacitance, the high-voltage arm capacitance, and the ideal voltage division ratio; if not, it adds a shielding structure, and obtains updated assembly parameters by adjusting the height parameter of the shielding. The high-voltage arm capacitance of the transient measurement structure is then updated and calculated based on the fixed structural parameters and the updated assembly parameters until the range design is met, resulting in the final assembly parameters. Based on this, this application provides a hand-hole capacitive voltage divider assembly structure that meets the requirements for transient voltage measurement on the end side of a direct-connected busbar power transformer, adaptable to direct-connected busbar power transformers of different specifications, thereby enabling the determination of transient parameters under different transformer voltage levels and different busbar sizes.

[0048] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0049] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0050] Figure 1 This invention provides a flowchart illustrating one of the steps in determining the transient measurement assembly structure of a direct-connected transformer according to an embodiment of the present invention.

[0051] Figure 2 This shows one of the block diagrams of the transient measurement assembly structure of the direct-connected transformer provided in the embodiment of the present invention;

[0052] Figure 3 This is a second block diagram of the transient measurement assembly structure of the direct-connected transformer provided in an embodiment of the present invention;

[0053] Figure 4 A step-by-step flowchart of step 400 in an embodiment of the present invention is shown;

[0054] Figure 5 A schematic diagram of the initial geometric assembly model in an embodiment of the present invention is shown;

[0055] Figure 6 A step-by-step flowchart of step 403 in an embodiment of the present invention is shown;

[0056] Figure 7 A step-by-step flowchart of step 500 in an embodiment of the present invention is shown;

[0057] Figure 8 A step-by-step flowchart of step 700 in an embodiment of the present invention is shown;

[0058] Figure 9 This diagram illustrates the structural schematic of the transient measurement assembly structure determination system for a direct-connected transformer provided in an embodiment of the present invention.

[0059] Figure 10 A schematic diagram of the server structure provided in an embodiment of the present invention is shown.

[0060] Icons: 10-Transient measurement assembly structure determination system for direct-connected transformer; 101-Ideal voltage division ratio determination module; 102-Low-voltage arm capacitance determination module; 103-High-voltage arm capacitance determination module; 104-Range judgment module; 20-Server; 21-Memory; 22-Processor; 23-Communication module. Detailed Implementation

[0061] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0062] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0063] It should be noted that relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0064] Please refer to Figure 1 , Figure 1 This invention illustrates a flowchart of the steps for determining the transient measurement assembly structure of a direct-connected transformer. This method is applied to a transient measurement structure, which is assembled at the handhole of the direct-connected transformer. The transient measurement structure includes an induction electrode and an insulating film. The direct-connected transformer includes a busbar. In this embodiment, the method for determining the transient measurement assembly structure includes steps 100 to 700.

[0065] Step 100: Obtain the rated parameters and fixed structure parameters of the direct-connected transformer.

[0066] The rated parameters include the rated voltage and the maximum voltage measurement range; the fixed structure parameters include at least the outer radius of the conductive rod of the tube socket, the length of the conductive rod, the inner radius of the metal shell, the width of the hand hole, the height of the hand hole, and the inner chamfer radius of the hand hole.

[0067] Step 200: Determine the ideal voltage divider ratio based on the rated voltage and the maximum voltage measurement range.

[0068] Step 300: Determine the low-voltage arm capacitance of the transient measurement structure based on the ideal voltage division ratio, and obtain the initial assembly parameters of the transient measurement structure.

[0069] In this embodiment, the low-voltage arm capacitance represents the self-capacitance of the sensing electrode to ground; the initial assembly parameters include at least the radius and thickness of the sensing electrode, and the material and thickness of the insulating film.

[0070] Step 400: Determine the high-voltage arm capacitance of the transient measurement structure based on the initial assembly parameters and fixed structural parameters.

[0071] In this embodiment, the high-voltage arm capacitor is used to characterize the mutual capacitance between the inductive electrode and the conductive rod in the tube.

[0072] Step 500: Determine whether the current transient measurement structure meets the range design based on the high-voltage arm capacitor, low-voltage arm capacitor, and ideal voltage division ratio of the transient measurement structure.

[0073] Step 600: If satisfied, the initial assembly parameters of the current transient measurement structure shall be used as the final assembly parameters.

[0074] Step 700: If not satisfied, add a shielding structure, obtain updated assembly parameters by adjusting the height parameter of the shielding, update the high-voltage arm capacitance of the transient measurement structure based on the fixed structure parameters and the updated assembly parameters, and return to the step of determining whether the current transient measurement structure meets the range design based on the high-voltage arm capacitance, low-voltage arm capacitance and ideal voltage division ratio of the current transient measurement structure.

[0075] Based on this, this application determines the high-voltage arm capacitance of the current transient measurement structure based on initial assembly parameters such as fixed structural parameters. The high-voltage arm capacitance, low-voltage arm capacitance, and ideal voltage division ratio under the current initial assembly parameters are then used to determine whether the current transient measurement structure meets the range design. If not, a shield is added to construct an optimized transient measurement structure. The initial assembly parameters are then updated based on the height of the shield to obtain the updated assembly parameters. The high-voltage arm capacitance of the transient measurement structure is then improved by adjusting the height parameter of the shield, ensuring that the transient measurement structure meets the range design. The height of the shield corresponding to meeting the range design is taken as the final height. Finally, the final assembly parameters are constructed using parameters including the height of the shield, the radius of the sensing electrode, and the material and thickness of the insulating film. This results in a transient measurement sensor assembly structure suitable for different direct-connected transformers, enabling the determination of transient voltage measurement methods for different transformer voltage levels and different transformer bus sizes.

[0076] In one possible implementation, the transient measurement structure could be a hand-held capacitive voltage divider; please refer to [reference needed]. Figure 2 , Figure 2This diagram illustrates the structural design of a transient measurement assembly structure for a direct-connected transformer according to an embodiment of the present invention. The transient measurement structure includes induction electrodes, an insulating film, and an electromagnetic shielding box for other accessories of the impedance transformation unit. Please refer to [link / reference needed]. Figure 2 In this embodiment, the tube includes a conductive rod and a metal shell.

[0077] Please Figure 2 Based on, refer to Figure 3 , Figure 3 This diagram illustrates another structural schematic of the transient measurement assembly structure for a direct-connected transformer according to an embodiment of the present invention. This transient measurement structure also includes a shielding cover. The design parameters of the shielding cover, except for its height, can be determined based on the fundamental parameters of the transient measurement structure. For example, the inner radius of the shielding cover, the outer radius of the disk, and the size of the bolt fixing platform are determined based on the radius of the induction electrode, the radius of the original hand hole, and the screw holes of the cover plate, among other device parameters. In one possible implementation, the inner radius of the shielding cover is chosen to be 5 mm larger than the radius of the induction electrode, and the outer radius of the shielding cover disk is chosen to be 5 mm smaller than the radius of the original hand hole.

[0078] To ensure that the maximum field strength of the shield is lower than the preset handhole design position, in this embodiment, the chamfer radii of both corners of the shield are selected to be equal to or greater than the chamfer radius of the original handhole.

[0079] It should be noted that this embodiment does not limit the implementation method of the direct-connected transformer and transient measurement structure; the above embodiment is only a schematic diagram.

[0080] Based on this, the assembly parameters in this embodiment include the structural parameters of the sensing electrode, the insulating film, and the tube housing, as well as the height of the shielding cover.

[0081] Based on the above structural diagram, the following will describe in detail the implementation of the method for determining the transient measurement assembly structure of the direct-connected transformer in this embodiment.

[0082] Obtain the rated voltage and maximum voltage measurement range of the direct-connected transformer. The rated voltage can be the rated voltage of the transformer's designed terminal side. The maximum voltage measurement range can be the maximum range of measuring elements such as impedance transformers in direct-connected transformers. .

[0083] Based on this, the ideal partial pressure ratio in this application The calculation formula can be expressed as:

[0084] .

[0085] Meanwhile, based on the voltage division principle of a hand-held capacitive voltage divider, namely that the capacitive voltage divider has a basically constant voltage division ratio within the measurable frequency range, the ideal voltage division ratio is... It is also approximately equal to the low-voltage arm capacitance C. L With high voltage arm capacitor C H The ratio between them can be expressed as:

[0086] .

[0087] Among them, the high-voltage arm capacitor can be the mutual capacitance between the induction electrode and the conductive rod in the tube; the low-voltage arm capacitor can be the self-capacitance of the induction electrode to ground.

[0088] To meet the range requirements, in this embodiment, the ratio between the low-voltage arm capacitor and the high-voltage arm capacitor must be greater than or equal to the aforementioned ideal voltage divider ratio. .

[0089] In this embodiment, the low-voltage arm capacitor can be determined by the size of the sensing electrode of the hand-hole capacitive voltage divider, the dielectric constant of the insulating film, and its thickness.

[0090] Among them, the low-voltage arm capacitor C L The calculation formula can be expressed as:

[0091] ;

[0092] In the formula, The vacuum permittivity, The relative permittivity of the insulating film. The thickness of the insulating film. Where is the electrode radius.

[0093] To achieve the highest possible voltage division ratio while simultaneously ensuring the high-frequency characteristics of the capacitor divider at the hundred-MHz level and avoiding parasitic oscillations on the electrodes, the low-voltage arm capacitor C in this embodiment... L The ideal capacitance value can be in the range of 1~10nF. Based on this, this embodiment can ensure that the low-voltage arm capacitance value is in the ideal range by determining the size of the sensing electrode and the insulating film material.

[0094] In one possible implementation, this embodiment may employ a sensing electrode with a radius of 50 mm and a thickness of 20 mm, and use a 25-micron-thick polytetrafluoroethylene film as an insulating film, thereby incorporating the aforementioned low-voltage arm capacitor C. L Keep it around 4nF.

[0095] Once the ideal voltage division ratio is determined, this embodiment can determine the low-voltage arm capacitor based on the above technical principles and obtain initial assembly parameters including the radius of the sensing electrode, the material and thickness of the insulating film.

[0096] Determine the ideal partial pressure ratio and low-voltage arm capacitor C L Please refer to the following: Figure 4 ,Figure 4 The following is a flowchart of step 400 in an embodiment of the present invention, which includes steps 401 to 403.

[0097] Step 401: Construct an initial geometric assembly model based on the radius of the induction electrode, the material and thickness of the insulating film, the outer radius of the conductive rod of the tube, the length of the conductive rod, the inner radius of the metal shell, the width of the hand hole, the height of the hand hole, and the inner chamfer radius of the hand hole.

[0098] Step 402: Determine the electrostatic field corresponding to the initial geometric assembly model.

[0099] Step 403: Determine the high-voltage arm capacitance of the transient measurement structure based on the electrostatic field corresponding to the initial geometric assembly model using the finite element method.

[0100] In this embodiment, the fixed structural parameters of the direct-connected transformer need to be obtained at least including the outer radius of the conductive rod of the busbar. R c Length of conductive rod L Inner radius of metal casing R s Handhole width W Handhole height H Chamfer radius of the hand hole R d .

[0101] Based on this, this application can be based on the aforementioned fixed structural parameters and the radius of the sensing electrode under the capacitor voltage divider. R e Electrode thickness D Insulating film thickness M To construct the initial geometric model and determine the high-voltage arm capacitance of the transient measurement structure under the current assembly parameters.

[0102] In order to reduce the difficulty of mesh generation and solution without affecting the solution accuracy, in one possible implementation, the geometric model in this embodiment can ignore the thickness of the metal shell and directly represent it with the inner surface; the guide rod can be represented with the outer surface; the size of the fixing parts such as the electrode screws of the capacitor voltage divider can be ignored; and a material with a thickness on the micrometer scale can be used as an insulating film.

[0103] To improve convergence, in one possible implementation, the insulating film in this embodiment can be represented by a surface, and its radius is set to be 2 mm larger than the radius of the sensing electrode.

[0104] Please refer to Figure 5 , Figure 5The diagram shows a schematic of the initial geometric assembly model in an embodiment of the present invention. The initial geometric assembly model shows a three-conductor system between the metal shell (grounded) at the tube shank, the conductive rod, and the induction electrode. In the diagram, conductor 1 is the conductive rod, conductor 2 is the electrode, and surfaces 1, 2, and 3 are schematic diagrams of the tube shank under the model.

[0105] Please Figure 5 Based on, refer to Figure 6 , Figure 6 The flowchart of step 403 in an embodiment of the present invention is shown. Step 403 includes steps 403-1 to 403-2.

[0106] Step 403-1: Determine the electric field energy density corresponding to the initial geometric assembly model based on the electrostatic field domain corresponding to the initial geometric assembly model.

[0107] Step 403-2: Determine the high-voltage arm capacitance of the transient measurement structure based on the electric field energy density corresponding to the initial geometric assembly model using the finite element method.

[0108] Based on this, the calculation formula for the high-voltage arm capacitance of the transient measurement structure in this embodiment is expressed as:

[0109] ;

[0110] in, The high-voltage arm capacitor of the transient measurement structure; The terminal voltage of the conductive rod in the tube is denoted as . This is the terminal voltage of the sensing electrode; This represents the electric field energy density corresponding to the initial geometric assembly model.

[0111] In one possible implementation, the electric field energy density corresponding to the initial geometric assembly model in this embodiment is determined as follows:

[0112] (1) Set the terminal voltage of conductor 1 satisfy: Simultaneously, the terminal voltage of conductor 2 is also set. satisfy: .

[0113] (2) Set all surfaces of the housing and handhole cover to be grounded, that is, the voltage of each surface is zero.

[0114] (3) Set surfaces 1 and 2 to satisfy the zero-charge boundary condition equation, which is expressed as: In the formula, For electric flux density, is the unit normal vector of the boundary (i.e., "face 1" and "face 2").

[0115] (4) Set the boundary condition equation for surface 3 to satisfy the electric displacement field normal vector. The boundary condition equation is expressed as: In the formula, , These are the electric flux densities on both sides of the "face 3" interface; For tangential gradient operators; The potential is given. The relative permittivity of the polytetrafluoroethylene film material in this embodiment is also given. ,thickness To be set as an intrinsic parameter, where, for the dielectric constant It can be 4, thickness It can be 25 micrometers.

[0116] The partial differential equations constituting the above boundary conditions can be solved by introducing the finite element method through free tetrahedral mesh generation, thus obtaining the electric field energy density corresponding to the initial geometric assembly model. This leads to the obtaining of the high-voltage arm capacitance of the transient measurement structure. .

[0117] The high-voltage arm capacitance of the transient measurement structure is obtained. Please refer to the following: Figure 7 , Figure 7 The following is a flowchart of step 500 in an embodiment of the present invention, which includes steps 501 to 502.

[0118] Step 501: Calculate the ideal high voltage arm capacitance based on the ideal voltage division ratio and the low voltage arm capacitance.

[0119] Step 502: Determine whether the high-voltage arm capacitance of the transient measurement structure is less than or equal to the ideal high-voltage arm capacitance.

[0120] The formula for calculating the capacitance of the ideal high-voltage arm satisfies:

[0121] ;

[0122] In the formula, The ideal high-voltage arm capacitance value; Ideal partial pressure ratio; This is the capacitance value of the low-voltage arm.

[0123] Based on this, if the capacitance is less than or equal to the ideal high-voltage arm capacitance, it is determined that the current transient measurement structure meets the range design. Then, the radius and thickness of the induction electrode and the material and thickness of the insulating film calculated above are used as the final output.

[0124] Conversely, the initial assembly parameters are updated based on the height of the shield, and the high-voltage arm capacitance of the transient measurement structure is updated based on the fixed structural parameters and the updated assembly parameters, until the current transient measurement structure meets the range design, thus obtaining the final assembly parameters.

[0125] Please refer to Figure 8 , Figure 8 The following is a flowchart of step 700 in an embodiment of the present invention, which includes steps 701 to 703.

[0126] Step 701: Based on the height parameters of the shielding cover and the outer radius, length, inner radius, handhole width, handhole height, and inner chamfer radius of the conductive rod of the tube, construct an optimized geometric assembly model.

[0127] Step 702: Establish the electrostatic field of the optimized geometric assembly model.

[0128] Step 703: Calculate the high-voltage arm capacitance of the transient measurement structure based on the electrostatic field of the optimized geometric assembly model using the finite element method.

[0129] The difference between the optimized geometric assembly model in this embodiment and the initial geometric assembly model in the previous embodiment is that a shielding cover is added, and the height parameter of the shielding cover is introduced into the initial geometric assembly model.

[0130] Based on this, a shield boundary condition was added to the boundary conditions of the optimized geometric assembly model. The shield boundary was set to ground and connected to the handhole cover.

[0131] Specifically, in this embodiment, the initial assembly parameters are first updated based on the height of the shielding cover. That is, the height of the shielding cover is added to the initial assembly parameters to obtain the updated assembly parameters. The electrostatic field under the geometric assembly model corresponding to the updated assembly parameters and the outer radius, length, inner radius, hand hole width, hand hole height, and inner chamfer radius of the hand hole of the tube nut is calculated. Then, the high voltage arm capacitance of the transient measurement structure is determined. Based on the high voltage arm capacitance and ideal voltage division ratio of the transient measurement structure, it is determined whether the current transient measurement structure meets the range design. If it does not meet the design, the height is used as a global parameter, and the height value is increased from zero according to a preset step size until the current transient measurement structure meets the range design. The height of the shielding cover corresponding to the design range is output and used as the final height of the shielding cover. The radius of the sensing electrode, the material and thickness of the insulating film, etc., are used as the final assembly parameters.

[0132] Specifically, in this embodiment, after determining the high-voltage arm capacitance of the transient measurement structure under the current parameter state based on the initial geometric assembly model constructed by the radius of the sensing electrode, the material and thickness of the insulating film, and the outer radius, length, inner radius, width, height, and chamfer radius of the conductive rod of the tube housing, if it is determined that the high-voltage arm capacitance of the transient measurement structure does not meet the ideal high-voltage arm capacitance value, a shielding structure will be added on the basis of the transient measurement structure, and the height of the shielding structure will be adjusted to make the transient measurement structure meet the preset range.

[0133] The height of the shielding structure is adjusted from zero according to a preset step size. Taking a two-iteration process as an example, in the first iteration, the initial height of the shielding structure is assumed to be h1. Based on this initial height value h1 and the outer radius of the conductive rod of the tube, the height of the shielding structure is adjusted from zero. R c Length of conductive rod L Inner radius of metal casing R s Handhole width W Handhole height H Chamfer radius of the hand hole R d After constructing the geometric assembly model, the obtained high-voltage arm capacitance is not equal to the ideal high-voltage arm capacitance value. At this time, the second iteration process is entered. Based on the initial height value h1, a preset step size a is added to obtain the height of the updated shield structure. Then, based on the height value h1+a, the high-voltage arm capacitance of the corresponding model is calculated a second time. If the high-voltage arm capacitance equals the ideal high-voltage arm capacitance value after the second calculation, then the height value h1+a is taken as the final height of the shield structure, and the radius and thickness of the sensing electrode and the material and thickness of the insulating film obtained at the beginning are taken as the final output.

[0134] In one possible implementation, the preset step size a in this embodiment can be 1 millimeter.

[0135] Based on this, under the condition that the transient measurement structure under the current assembly parameters does not meet the ideal voltage division ratio of the corresponding direct-connected transformer, this embodiment can adjust the height of the shielding cover so that the high-voltage arm capacitor and the low-voltage arm capacitor corresponding to the transient measurement structure can meet the ideal voltage division ratio.

[0136] Based on this, this application provides a general scheme for determining the assembly structure of transient measurement sensors applicable to direct-connected transformers. By adjusting the above method, it adapts to the ideal voltage division ratio corresponding to different direct-connected transformers, thereby being compatible with direct-connected power transformers of different specifications.

[0137] The same idea applies as the previous embodiment; please refer to [the previous embodiment]. Figure 9 , Figure 9This diagram illustrates the structure of a transient measurement assembly structure determination system for a direct-connected transformer according to an embodiment of the present invention. The system 10 is applied to a transient measurement structure, which is assembled at the handhole of the direct-connected transformer. The transient measurement structure includes induction electrodes and an insulating film. The direct-connected transformer includes a busbar, comprising:

[0138] The ideal voltage division ratio determination module 101 is used to obtain the rated parameters and fixed structural parameters of the direct-connected transformer with a busbar; wherein, the rated parameters include the rated voltage and the maximum voltage measurement range; the fixed structural parameters include at least the outer radius of the conductive rod of the busbar, the length of the conductive rod, the inner radius of the metal shell, the width of the hand hole, the height of the hand hole, and the inner chamfer radius of the hand hole; and the ideal voltage division ratio is determined based on the rated voltage and the maximum voltage measurement range.

[0139] The low-voltage arm capacitance determination module 102 is used to determine the low-voltage arm capacitance of the transient measurement structure based on the ideal voltage division ratio and obtain the initial assembly parameters of the transient measurement structure; the low-voltage arm capacitance characterizes the self-capacitance of the sensing electrode to ground; the initial assembly parameters include at least the radius and thickness of the sensing electrode, and the material and thickness of the insulating film;

[0140] The high-voltage arm capacitance determination module 103 is used to determine the high-voltage arm capacitance of the transient measurement structure based on the initial assembly parameters and fixed structure parameters; the high-voltage arm capacitance is used to characterize the mutual capacitance between the induction electrode and the conductive rod in the tube.

[0141] The range judgment module 104 is used to determine whether the current transient measurement structure meets the range design based on the high voltage arm capacitance, low voltage arm capacitance and ideal voltage division ratio of the transient measurement structure.

[0142] The range determination module 104 is also used to determine that the current transient measurement structure meets the range design, and then use the initial assembly parameters of the current transient measurement structure as the final assembly parameters.

[0143] The range judgment module 104 is also used to determine that the current transient measurement structure does not meet the range design, add a shield structure, obtain updated assembly parameters by adjusting the height parameter of the shield, update the high voltage arm capacitance of the transient measurement structure based on the fixed structure parameters and the updated assembly parameters, and return the steps of judging whether the current transient measurement structure meets the range design based on the high voltage arm capacitance, low voltage arm capacitance and ideal voltage division ratio of the current transient measurement structure.

[0144] The same idea applies as the previous embodiment; please refer to [the previous embodiment]. Figure 10 , Figure 10A schematic diagram of the server structure in an embodiment of the present invention is shown. The server 20 includes a memory 21, a processor 22, and a communication module 23. The memory 21, processor 22, and communication module 23 are electrically connected to each other directly or indirectly to realize data transmission or interaction. For example, these components can be electrically connected to each other through one or more communication buses or signal lines.

[0145] The memory 21 is used to store programs or data. The memory may be, but is not limited to, random access memory (RAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), etc.

[0146] The processor 22 is used to read / write data or programs stored in the memory and execute corresponding functions. For example, it first obtains the fixed structural parameters and the rated voltage and maximum voltage measurement range of the direct-connected transformer; then, it determines the ideal voltage division ratio based on the rated voltage and maximum voltage measurement range; simultaneously, it determines the low-voltage arm capacitance of the transient measurement structure based on the ideal voltage division ratio and obtains the initial assembly parameters of the transient measurement structure. Subsequently, it determines the high-voltage arm capacitance of the transient measurement structure based on the initial assembly parameters and the fixed structural parameters; then, it judges whether the current transient measurement structure meets the range design based on the low-voltage arm capacitance, the high-voltage arm capacitance, and the ideal voltage division ratio; if it does not meet the requirements, it adds a shielding structure, obtains updated assembly parameters by adjusting the height parameter of the shielding, and updates the calculation of the high-voltage arm capacitance of the transient measurement structure based on the fixed structural parameters and the updated assembly parameters until the range design is met, and obtains the final assembly parameters.

[0147] The communication module 23 is used to establish a communication connection between the server and other communication terminals through the network, and to send and receive data through the network.

[0148] It should be understood that, Figure 10 The structure shown is only a schematic diagram of the server structure; the server may also include components such as... Figure 10 The more or fewer components shown, or having the same Figure 10 The different configurations shown. Figure 10 The components shown can be implemented using hardware, software, or a combination thereof.

[0149] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can also be implemented in other ways. The apparatus embodiments described above are merely illustrative; for example, the flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of apparatus, methods, and computer program products according to various embodiments of the present invention. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than those marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram and / or flowchart, and combinations of blocks in block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0150] In addition, the functional modules in the various embodiments of the present invention can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0151] If the aforementioned functions are implemented as software functional modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0152] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for determining the transient measurement assembly structure of a direct-connected transformer, applied to a transient measurement structure, wherein the transient measurement structure is assembled at the handhole of the direct-connected transformer, the transient measurement structure includes an induction electrode and an insulating film, and the direct-connected transformer includes a busbar, characterized in that, The method for determining the transient measurement assembly structure of the direct-connected busbar transformer includes: Obtain the rated parameters and fixed structure parameters of the direct-connected transformer; wherein the rated parameters include rated voltage and maximum voltage measurement range; wherein the fixed structure parameters include at least the outer radius of the conductive rod of the transformer, the length of the conductive rod, the inner radius of the metal shell, the width of the hand hole, the height of the hand hole, and the inner chamfer radius of the hand hole; Determine the ideal voltage divider ratio based on the rated voltage and the maximum voltage measurement range; The low-voltage arm capacitance of the transient measurement structure is determined based on the ideal voltage division ratio, and the initial assembly parameters of the transient measurement structure are obtained; the low-voltage arm capacitance characterizes the self-capacitance of the sensing electrode to ground; the initial assembly parameters include at least the radius and thickness of the sensing electrode, and the material and thickness of the insulating film; The high-voltage arm capacitance of the transient measurement structure is determined based on the initial assembly parameters and the fixed structure parameters; the high-voltage arm capacitance is used to characterize the mutual capacitance between the sensing electrode and the conductive rod in the tube. The ideal high-voltage arm capacitance is calculated based on the ideal voltage division ratio and the low-voltage arm capacitance; wherein, the formula for calculating the ideal high-voltage arm capacitance satisfies: ； in, The ideal high-voltage arm capacitance value; Ideal partial pressure ratio; The capacitance value is for the low-voltage arm. Determine whether the high-voltage arm capacitance of the transient measurement structure is less than or equal to the ideal high-voltage arm capacitance; If it is less than or equal to, then the current transient measurement structure is determined to meet the range design, and the initial assembly parameters of the current transient measurement structure are used as the final assembly parameters. If the requirements are not met, a shielding structure is added, and the updated assembly parameters are obtained by adjusting the height parameter of the shielding structure. The high-voltage arm capacitance of the transient measurement structure is updated and calculated based on the fixed structure parameters and the updated assembly parameters. The process of determining whether the current transient measurement structure meets the range design is then returned based on the high-voltage arm capacitance, the low-voltage arm capacitance, and the ideal voltage division ratio of the current transient measurement structure.

2. The method for determining the transient measurement assembly structure of a direct-connected transformer according to claim 1, characterized in that, The steps for determining the high-voltage arm capacitance of the transient measurement structure based on the initial assembly parameters and the fixed structural parameters include: An initial geometric assembly model is constructed based on the radius and thickness of the sensing electrode, the material and thickness of the insulating film, and the outer radius, length, inner radius, handhole width, handhole height, and inner chamfer radius of the conductive rod of the tube nut. Determine the electrostatic field domain corresponding to the initial geometric assembly model; The high-voltage arm capacitance of the transient measurement structure is determined using the finite element method based on the electrostatic field corresponding to the initial geometric assembly model.

3. The method for determining the transient measurement assembly structure of a direct-connected transformer according to claim 2, characterized in that, The steps for determining the high-voltage arm capacitance of the transient measurement structure using the finite element method based on the electrostatic field corresponding to the initial geometric assembly model include: The electric field energy density corresponding to the initial geometric assembly model is determined based on the electrostatic field domain corresponding to the initial geometric assembly model. The high-voltage arm capacitance of the transient measurement structure is determined using the finite element method based on the electric field energy density corresponding to the initial geometric assembly model.

4. The method for determining the transient measurement assembly structure of a direct-connected transformer according to claim 3, characterized in that, The formula for calculating the high-voltage arm capacitance of the transient measurement structure based on the electric field energy density corresponding to the initial geometric assembly model using the finite element method is expressed as follows: ； in, The high-voltage arm capacitor of the transient measurement structure; The terminal voltage of the conductive rod in the tube is denoted as . The terminal voltage of the sensing electrode; The electric field energy density corresponds to the initial geometric assembly model.

5. The method for determining the transient measurement assembly structure of a direct-connected transformer according to claim 1, characterized in that, The calculation formula for obtaining the initial assembly parameters of the transient measurement structure is expressed as follows: ； in, The low-voltage arm capacitor of the transient measurement structure; The vacuum permittivity, The relative permittivity of the insulating film is denoted as . The thickness of the insulating film is given. The radius of the sensing electrode is given.

6. The method for determining the transient measurement assembly structure of a direct-connected transformer according to claim 1, characterized in that, The steps for updating and calculating the high-voltage arm capacitance of the transient measurement structure based on the fixed structural parameters and the updated assembly parameters include: An optimized geometric assembly model is constructed based on the height parameters of the shielding cover and the outer radius, length, inner radius, handhole width, handhole height, and inner chamfer radius of the tube. Establish the electrostatic field domain of the optimized geometric assembly model; The high-voltage arm capacitance of the transient measurement structure is calculated using the finite element method based on the electrostatic field of the optimized geometric assembly model.

7. The method for determining the transient measurement assembly structure of a direct-connected transformer according to claim 6, characterized in that, The steps of adding a shielding structure and obtaining updated assembly parameters by adjusting the height parameter of the shielding structure include: The height of the shield is added to the initial assembly parameters, and the height is used as a global parameter to increase the height from zero in a preset step size until the current transient measurement structure meets the range design.

8. A transient measurement assembly structure determination system for a direct-connected transformer with a busbar, applied to a transient measurement structure, wherein the transient measurement structure is assembled at the handhole of the direct-connected transformer with a busbar, the transient measurement structure includes an induction electrode and an insulating film, and the direct-connected transformer with a busbar includes a busbar, characterized in that, include: An ideal voltage division ratio determination module is used to obtain the rated parameters and fixed structural parameters of a direct-connected transformer with a mains busbar; wherein, the rated parameters include the rated voltage and the maximum voltage measurement range; the fixed structural parameters include at least the outer radius of the conductive rod of the mains busbar, the length of the conductive rod, the inner radius of the metal shell, the width of the handhole, the height of the handhole, and the inner chamfer radius of the handhole; and to determine the ideal voltage division ratio based on the rated voltage and the maximum voltage measurement range; A low-voltage arm capacitance determination module is used to determine the low-voltage arm capacitance of the transient measurement structure based on the ideal voltage division ratio, and to obtain the initial assembly parameters of the transient measurement structure; the low-voltage arm capacitance characterizes the self-capacitance of the sensing electrode to ground; the initial assembly parameters include at least the radius and thickness of the sensing electrode, and the material and thickness of the insulating film; A high-voltage arm capacitance determination module is used to determine the high-voltage arm capacitance of the transient measurement structure based on the initial assembly parameters and the fixed structure parameters; the high-voltage arm capacitance is used to characterize the mutual capacitance between the sensing electrode and the conductive rod in the tube nut. The range determination module is used to calculate the ideal high-voltage arm capacitance based on the ideal voltage division ratio and the low-voltage arm capacitance; wherein the calculation formula for the ideal high-voltage arm capacitance satisfies: ； in, The ideal high-voltage arm capacitance value; Ideal partial pressure ratio; The capacitance value is for the low-voltage arm. Determine whether the high-voltage arm capacitance of the transient measurement structure is less than or equal to the ideal high-voltage arm capacitance; The range determination module is further configured to determine that the current transient measurement structure meets the range design if the range is less than or equal to the specified range, and then use the initial assembly parameters of the current transient measurement structure as the final assembly parameters. The range determination module is further configured to, after determining that the current transient measurement structure does not meet the range design, add a shielding structure, obtain updated assembly parameters by adjusting the height parameter of the shielding, update and calculate the high-voltage arm capacitance of the transient measurement structure based on the fixed structure parameters and the updated assembly parameters, and return the steps of determining whether the current transient measurement structure meets the range design based on the high-voltage arm capacitance, the low-voltage arm capacitance, and the ideal voltage division ratio of the current transient measurement structure.

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