Transformer iron core no-load performance analysis method and system, computer equipment and storage medium

Abstract

The invention provides a transformer iron core no-load performance analysis method and system, computer equipment and a storage medium, and belongs to the technical field of transformer iron core design, and the method comprises the steps: obtaining the hysteresis loss and eddy current loss of a single silicon steel sheet in an iron core; determining the loss of a single seam area of the iron core according to the hysteresis loss and the eddy-current loss of a single silicon steel sheet in the iron core; determining the total loss of the iron core according to the loss of the single joint area of the iron core; obtaining silicon steel sheet section average magnetic field intensity; determining no-load current of the iron core according to the average magnetic field intensity of the silicon steel sheet section; and analyzing the no-load performance of the transformer core according to the total loss and the no-load current of the core. According to the method, the influence of the stepping lap joint mode at the iron core seam, the paint film thickness, the material sheet thickness and the gap size on the no-load performance of the transformer is considered, and the problems of iron core no-load loss and no-load current design exceeding the standard are avoided.

Description

Technical Field

[0001] The invention belongs to the technical field of transformer core design, and in particular relates to a transformer core no-load performance analysis method, system, computer equipment and storage medium. Background Art

[0002] The no-load performance of the transformer core mainly includes no-load loss and no-load current. By measuring the no-load current and loss, the efficiency, power factor and energy consumption of the transformer can be evaluated, which is crucial for the design and selection of the transformer.

[0003] At present, the calculation of transformer core no-load loss mainly adopts the formula method, which is based on the product of unit mass and specific total loss, supplemented by a process coefficient. The problem with this algorithm is that the core is regarded as a homogeneous material, and the specific total loss of the material is only related to the power supply excitation frequency and the core magnetic flux density, but silicon steel is not a homogeneous material and the electromagnetic characteristics of the core joint are also very complex (this complex characteristic is mainly due to the change of the main magnetic flux direction at the joint and the more complex structure of the joint than the core column area). The formula method cannot reflect the influence of the step lap method, paint film thickness, material sheet thickness, gap size, etc. at the core joint on the no-load performance, so that the premise of formula derivation is no longer valid in the joint area. Obviously, the formula method has a large calculation error when used for the calculation of the entire core, and it cannot be used for the research work of joint structure optimization.

[0004] For no-load current, the engineering community has used experience-based estimates based on the material unit magnetization capacity and joint magnetization capacity, or used the finite element method to calculate no-load loss. However, the above methods all treat the core as a homogeneous whole for derivation and calculation, ignoring factors such as step-by-step lap joints, paint film, and gap separation, resulting in no-load current exceeding the standard in production. Summary of the invention

[0005] The present invention provides a transformer core no-load performance analysis method, system, computer equipment and storage medium to reduce the influence of the prior art on the transformer no-load performance analysis of the step-over method, paint film thickness, material sheet thickness and gap size at the core joint.

[0006] In a first aspect, the present invention provides a method for analyzing no-load performance of a transformer core, comprising:

[0007] Obtain the hysteresis loss and eddy current loss of a single silicon steel sheet in the iron core;

[0008] According to the hysteresis loss and eddy current loss of a single silicon steel sheet in the core, the loss of a single joint area of ​​the core is determined;

[0009] Determine the total loss of the core based on the loss of a single seam area of ​​the core;

[0010] Obtain the average magnetic field strength of the silicon steel sheet cross section;

[0011] The no-load current of the core is determined based on the average magnetic field strength of the silicon steel sheet cross section; the no-load performance of the transformer core is analyzed based on the total loss of the core and the no-load current.

[0012] Optionally, determining the loss of a single joint area of ​​the core according to the hysteresis loss and eddy current loss of a single silicon steel sheet in the core includes:

[0013] The loss P of a single joint area of ​​the core is calculated according to the following formula 1 :

[0014]

[0015] Among them, k is the core lamination coefficient; h 1 is the core lamination height; n is the total number of silicon steel sheets in one step of the joint area; m is the number of silicon steel sheets in each stack; b 1 is the number of steps in the step-by-step overlap method of silicon steel sheets; h is the thickness of a single silicon steel sheet; P hi is the hysteresis loss of the i-th silicon steel sheet; P oi is the eddy current loss of the i-th silicon steel sheet.

[0016] Optionally, determining the total loss of the core according to the loss of a single joint area of ​​the core includes:

[0017] Obtain the unit iron loss P' under the average magnetic flux density of the silicon steel sheet cross section;

[0018] The total core loss P is calculated according to the following formula 总 :

[0019] P 总 =4P 1 +b·k·h 1 ·d·P'·ρ;

[0020] Among them, P 1 is the loss of a single joint area of ​​the core; b is the width of a single silicon steel sheet; k is the core lamination coefficient; h 1 is the height of the core laminations; d is the total length of the core column and yoke excluding the joints in the core; ρ is the density of the silicon steel sheet.

[0021] Optionally, determining the no-load current of the core according to the average magnetic field strength of the cross section of the silicon steel sheet includes:

[0022] Get the excitation current I of a single joint area in the core 1 and the number of turns N of the excitation wire;

[0023] Calculate the no-load current I of the core according to the following formula:

[0024]

[0025] Among them, H' is the average magnetic field intensity of the silicon steel sheet cross section; d is the total length of the core column and yoke obtained by excluding the joints in the iron core.

[0026] In a second aspect, the present invention provides a transformer core no-load performance analysis system, comprising:

[0027] The first acquisition module is used to obtain the hysteresis loss and eddy current loss of a single silicon steel sheet in the iron core;

[0028] The first determination module is used to determine the loss of a single joint area of ​​the core according to the hysteresis loss and eddy current loss of a single silicon steel sheet in the core;

[0029] The second determination module is used to determine the total loss of the core according to the loss of a single joint area of ​​the core;

[0030] The second acquisition module is used to obtain the average magnetic field strength of the cross section of the silicon steel sheet;

[0031] The third determination module is used to determine the no-load current of the core according to the average magnetic field strength of the silicon steel sheet cross section; and analyze the no-load performance of the transformer core based on the total loss of the core and the no-load current.

[0032] Optionally, the first determining module includes:

[0033] The first calculation unit is used to calculate the loss P of a single joint area of ​​the core according to the following formula 1 :

[0034]

[0035] Among them, k is the core lamination coefficient; h 1 is the core lamination height; n is the total number of silicon steel sheets in one step of the joint area; m is the number of silicon steel sheets in each stack; b 1 is the number of steps in the step-by-step overlap method of silicon steel sheets; h is the thickness of a single silicon steel sheet; P hi is the hysteresis loss of the i-th silicon steel sheet; P oi is the eddy current loss of the i-th silicon steel sheet.

[0036] Optionally, the second determining module includes:

[0037] The first acquisition unit is used to acquire the unit iron loss P' under the average magnetic flux density of the silicon steel sheet cross section;

[0038] The second calculation unit is used to calculate the total loss P of the core according to the following formula 总 :

[0039] P 总 =4P 1+b·k·h 1 ·d·P'·ρ;

[0040] Among them, P 1 is the loss of a single joint area of ​​the core; b is the width of a single silicon steel sheet; k is the core lamination coefficient; h 1 is the height of the core laminations; d is the total length of the core column and yoke excluding the joints in the core; ρ is the density of the silicon steel sheet.

[0041] Optionally, the third determining module includes:

[0042] The second acquisition unit is used to obtain the excitation current I of a single joint area in the iron core. 1 and the number of turns N of the excitation wire;

[0043] The third calculation unit is used to calculate the no-load current I of the core according to the following formula:

[0044]

[0045] Among them, H' is the average magnetic field intensity of the silicon steel sheet cross section; d is the total length of the core column and yoke obtained by excluding the joints in the iron core.

[0046] In a third aspect, the present invention provides a computer device comprising a processor and a memory; wherein, when the processor executes a computer program stored in the memory, the steps of the transformer core no-load performance analysis method described in the first aspect are implemented.

[0047] In a fourth aspect, the present invention provides a computer-readable storage medium for storing a computer program; when the computer program is executed by a processor, the steps of the transformer core no-load performance analysis method described in the first aspect are implemented.

[0048] The present invention provides a method, system, computer equipment and storage medium for analyzing the no-load performance of a transformer core, wherein the method comprises obtaining the hysteresis loss and eddy current loss of a single silicon steel sheet in the core; determining the loss of a single joint area of ​​the core according to the hysteresis loss and eddy current loss of the single silicon steel sheet in the core; determining the total loss of the core according to the loss of a single joint area of ​​the core; obtaining the average magnetic field strength of the cross section of the silicon steel sheet; determining the no-load current of the core according to the average magnetic field strength of the cross section of the silicon steel sheet; analyzing the no-load performance of the transformer core according to the total loss and no-load current of the core. The present invention takes into account the influence of the step-overlapping method, paint film thickness, material sheet thickness and gap size at the core joint on the no-load performance of the transformer, and avoids the problem of excessive design of no-load loss and no-load current of the core. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the technical solution of the present invention, the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0050] Figure 1 A schematic flow chart of a method for analyzing no-load performance of a transformer core provided by an embodiment of the present invention;

[0051] Figure 2 A schematic structural diagram of a transformer core no-load performance analysis system provided in an embodiment of the present invention.

[0052] Figure 3 A BH curve diagram of a silicon steel sheet provided in an embodiment of the present invention;

[0053] Figure 4 A BP curve diagram of a silicon steel sheet provided in an embodiment of the present invention;

[0054] Figure 5 The BP of the modified silicon steel sheet provided in the embodiment of the present invention is s Graphs;

[0055] Figure 6 A sketch of a joint without separation of a silicon steel sheet provided in an embodiment of the present invention;

[0056] Figure 7 A comparison chart of loss percentages under different stepping conditions provided by an embodiment of the present invention;

[0057] Figure 8 A comparison diagram of current percentages under different stepping conditions provided by an embodiment of the present invention;

[0058] Fig. 9 A comparison chart of the efficiency and accuracy of various multi-stack models provided in an embodiment of the present invention;

[0059] Fig.10 A positional relationship diagram of a silicon steel sheet and a paint film layer provided in an embodiment of the present invention;

[0060] Fig.11 A magnetic flux density distribution cloud diagram of a 5-step 4mm step joint provided in an embodiment of the present invention;

[0061] Fig.12 This is a cloud diagram of the eddy current loss distribution of a joint with a step size of 4 mm in 5 steps provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0062] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0063] Example 1

[0064] like Figure 1 As shown, this embodiment provides a method for analyzing no-load performance of a transformer core, including:

[0065] Step 101, obtaining the hysteresis loss and eddy current loss of a single silicon steel sheet in the iron core.

[0066] In this embodiment, the thickness h of the single silicon steel sheet with paint film on both sides is 0 The thickness of the core is 0.18mm, the iron core has a step size of 4mm in 5 steps, the silicon steel sheets are stacked one by one, the width of the silicon steel sheet is 100mm, the length of the silicon steel sheet is 500mm, and the stack thickness is 40mm.

[0067] In this step, the thickness of the paint film on one side of the single silicon steel sheet h' and the thickness of the single silicon steel sheet h 0 , the electrical conductivity σ of the silicon steel sheet and the density ρ of the silicon steel sheet.

[0068] like Figure 3 and Figure 4 As shown, the relationship curve between the magnetic flux density B and the loss P of the silicon steel sheet and the relationship curve between the magnetic flux density B and the magnetic field intensity H of the silicon steel sheet are obtained. Among them, the magnetic flux density is the magnetic induction intensity.

[0069] Calculate the thickness h of a single silicon steel sheet according to the following formula:

[0070] h=h 0 -2h'=0.173mm.

[0071] Calculate the eddy current loss coefficient K of a single silicon steel sheet according to the following formula e :

[0072]

[0073] Among them, π is the ratio of a circle to its circumference.

[0074] The classic eddy current loss P of the silicon steel sheet in the full magnetic flux density section at the test frequency f is calculated according to the following formula e :

[0075] P e =f 2 ·B 2 ·K e .

[0076] According to the calculation of silicon steel sheet residual loss P s , and get Figure 5 The magnetic flux density B and the residual loss P of the silicon steel sheet are shown s The BP curve obtained from the test shows that at any magnetic flux density B, P s =PP e .

[0077] Create a 3D model of the core in MAGNET software:

[0078] 1) Click Create Model Material and enter the obtained silicon steel sheet parameters according to the steps. It should be noted that the BP curve data that needs to be entered needs to be changed to BP s Curve data.

[0079] 2) According to the required width of the silicon steel sheet, select about twice the length of the sheet width as the sheet length, such as Figure 6 So, sketch the seam without any gaps.

[0080] 3) Use the stretch command to stretch each silicon steel sheet into a three-dimensional sheet according to the core thickness and the sketch outline.

[0081] 4) Use the translation command to translate the silicon steel sheets in the vertical direction of the stacking by the total thickness of the silicon steel sheets. Some sheets need to be moved several times according to their relative positions. At this time, an air layer of the thickness of the paint film will appear between the silicon steel sheets, such as Fig.10 shown.

[0082] 5) Shift the silicon steel sheet as a whole to create a gap at the inclined joint.

[0083] 6) Draw the excitation wire and air bag, and make sure the edge of the air bag is flush with the end of the silicon steel sheet.

[0084] 7) Select the four copper wires in the model one by one, use Model→Make Simple Coil to generate the coil, click the Circuit command to enter the circuit diagram, and click Voltage Source to add a voltage source. Set the coil Type to Stranded, set No.ofTurns and StrandArea according to the designed magnetic flux density. Set the voltage size and waveform according to actual needs.

[0085] After the 3D model is established, the model needs to be simplified and corrected. The model simplification and correction includes the following steps:

[0086] 1) Select the silicon steel sheet surface that needs to be refined, and in the Mash Layers column of the right-click Properties page, set a layer of mesh in the middle of the silicon steel sheet; within the range of 10mm from the seam, the maximum mesh of the silicon steel sheet above and below the seam layer needs to be set to 1mm, and the other positions are set to 2-3mm. No special settings are required for other parts of the silicon steel sheet.

[0087] 2) Select the two surfaces that are flush with the air bag and the cross section of the silicon steel sheet, and set them as FieldNormal Boundary boundary conditions.

[0088] 3) Select the bottom surface of the air bag parallel to the silicon steel sheet, click Even Periodic Boundary, and set the corresponding translation distance to the thickness of each stack.

[0089] After the model is simplified and corrected, simulation needs to be performed. The simulation calculation includes the following steps:

[0090] 1) Click Solve → Set Solver Option and set the Polynomial order to 2. Set other parameters as required.

[0091] The post-processing calculation includes the following steps:

[0092] 1) Obtain the Hysteresis Loss (magnetic hysteresis loss) and Ohmic Loss (eddy current loss) of each silicon steel sheet in Results, and obtain the Current value, I' = 0.097956A.

[0093] 2) Obtain the RMS cloud diagram of the magnetic field intensity in Field, and obtain the average magnetic field intensity of the cross section of the silicon steel sheet at a point, which is calculated as H'; in this embodiment, H'=44.55 A / m.

[0094] 3) Obtain the magnetic flux density RMS cloud diagram in Field, and take a point to obtain the average magnetic flux density of the silicon steel sheet cross section, which is calculated as B'; in this embodiment, B'=1.5T.

[0095] Step 102, determining the loss of a single joint area of ​​the core according to the hysteresis loss and eddy current loss of a single silicon steel sheet in the core.

[0096] For example, the loss P of a single joint area of ​​the core is calculated according to the following formula: 1 :

[0097]

[0098] Among them, k is the core lamination coefficient; h 1 is the core lamination height; n is the total number of silicon steel sheets in one step of the joint area; m is the number of silicon steel sheets in each stack; b1 is the number of steps in the step-by-step overlap method of silicon steel sheets; h is the thickness of a single silicon steel sheet; P hi is the hysteresis loss of the i-th silicon steel sheet; P oi is the eddy current loss of the i-th silicon steel sheet.

[0099] In this embodiment,

[0100] Step 103, determining the total loss of the core according to the loss of a single joint area of ​​the core.

[0101] Exemplarily, in this step, it is necessary to obtain the unit iron loss P' under the average magnetic flux density of the cross section of the silicon steel sheet.

[0102] The total core loss P is calculated according to the following formula 总 :

[0103] P 总 =4P 1 +b·k·h 1 ·d·P'·ρ.

[0104] Among them, P 1 is the loss of a single joint area of ​​the core; b is the width of a single silicon steel sheet; k is the core lamination coefficient; h 1 is the height of the core laminations; d is the total length of the core column and yoke excluding the joints in the core; ρ is the density of the silicon steel sheet.

[0105] In this embodiment, d = 4 × (0.5-0.2 × 2) = 0.4m; b·k·h 1 ·d·P'·ρ=0.1×0.962×0.04×0.4×0.511×7650=6.01W; P 总 =4×4.650+6.01=24.61W.

[0106] Step 104, obtaining the average magnetic field strength of the cross section of the silicon steel sheet.

[0107] Step 105, determining the no-load current of the core according to the average magnetic field strength of the silicon steel sheet cross section; analyzing the no-load performance of the transformer core according to the total loss of the core and the no-load current.

[0108] For example, the number of turns N of the excitation wire in the three-dimensional model is obtained; the Current value of the silicon steel sheet obtained in Results is used as the excitation current I of a single joint area in the core. 1 .

[0109] Calculate the no-load current I of the core according to the following formula:

[0110]

[0111] Among them, H' is the average magnetic field intensity of the silicon steel sheet cross section; d is the total length of the core column and yoke obtained by excluding the joints in the iron core.

[0112] In this embodiment,

[0113] Obtain the required flux density cloud map and loss cloud map in Field to observe the core loss distribution, such as Fig.11 and Fig.12 As shown, the magnetic flux density distribution and eddy current loss distribution of the joint with a step size of 5 steps and 4 mm are respectively shown.

[0114] In order to solve the problem that the classical eddy current loss formula is not applicable to calculating the loss at the joint, this embodiment adopts a loss separation calculation method, which divides the iron loss into two parts, the classical eddy current loss and the other iron loss, and calculates them separately. The characteristics are:

[0115] 1) Correct the BP curve to BP before simulation calculation s Curve used to calculate the part of the joint other than the classical eddy current loss.

[0116] 2) The induced current caused by the magnetic flux penetrating the joint is calculated through refined finite element simulation, and the ohmic loss of the induced current in the silicon steel matrix is ​​calculated. This value is the actual eddy current loss at the joint, which is significantly different from the classic eddy current loss value.

[0117] In general models, eddy current losses are calculated using the classical eddy current loss formula. The classical eddy current loss formula is an approximate calculation based on the magnetic flux density but has nothing to do with the induced current in the silicon steel sheet. It is only applicable to locations in the core column or yoke where the magnetic flux density is uniform and there is no magnetic flux through the sheet. The error for calculating seams is large because eddy current losses are actually caused by induced current rather than magnetic flux density.

[0118] In order to reduce the calculation error, this embodiment adopts a single-piece modeling method, and the paint film thickness is modeled according to the full 1:1 modeling, and the gap size can be adjusted. The no-load performance of different joint forms can be accurately calculated, including multiple parameters such as piece width, number of steps, step amount, film thickness, gap size, etc., with the following characteristics:

[0119] 1) Only one stack of silicon steel sheets is selected as the simulation object, and the number of layers of silicon steel sheets is used as the step number, and each layer contains 2 sheets (side column joints) to 3 sheets (broken yoke middle column joints) of silicon steel sheets (if there are multiple sheets in a stack, the number of sheets will be doubled accordingly).

[0120] like Figure 7 and Figure 8As shown, the no-load performance of different joint stepping methods is demonstrated, and the accuracy is high enough to identify small differences, which is better than the existing finite element simulation calculation. This embodiment clearly defines the optimal stepping method for a small-capacity core with a magnetic density of 1.5T, that is, 5 steps of 3mm, and 4mm stepping is optimal (4mm can be selected considering the structural strength).

[0121] 2) The above silicon steel sheet thickness is the actual iron base thickness of the silicon steel sheet, not the nominal thickness.

[0122] 3) Each layer of silicon steel sheets mentioned above must include the paint film and the air gap between the stacking gaps, and the gaps cannot be ignored. The existence of the air gaps makes it unnecessary to use the approximate magnetic permeability setting in the stacking direction. This avoids the error caused by the equivalent setting.

[0123] 4) The above-mentioned gap can be adjusted within a certain range according to the process and research requirements, and the gap cannot be ignored, otherwise it will affect the calculation accuracy.

[0124] In order to avoid the problem of extremely low computational efficiency caused by the complexity of multi-stack single-piece modeling, this invention introduces the even-symmetric Even Periodic Boundary boundary condition, and can accurately characterize the characteristics of the entire core joint using only a single stack of silicon steel. The characteristics are:

[0125] 1) The even symmetric boundary is a parallel symmetric boundary condition rather than a rotational symmetric boundary in motor simulation.

[0126] 2) The translation distance Shift Vector of the symmetry boundary is the height of a cycle (the thickness of a stack of silicon steel sheets).

[0127] 3) The starting and ending positions of this boundary can be any position in the iron core parallel to the silicon steel surface, either in the air or inside the silicon steel sheet.

[0128] 4) This boundary must cover the upper and lower surfaces of the entire model (i.e. the upper and lower surfaces of the air bag).

[0129] In order to keep the joint magnetic circuit intact, the normal symmetric FieldNormal Boundary boundary condition is set at the model boundary, with the following characteristics:

[0130] 1) The rolling direction is perpendicular to the boundary conditions.

[0131] 2) Normal boundary conditions exist in pairs.

[0132] 3) Pairs of normal boundaries intersect and are at 90° to each other.

[0133] 4) The normal boundary condition is set on the surface of the air bag and completely covers the air bag surface.

[0134] In order to avoid the influence of high magnetic field near the coil on the silicon steel sheet in the single stack model, the excitation coil of this embodiment uses a straight wire instead of a traditional ring coil, which has the following characteristics:

[0135] 1) Straight conductors appear in pairs on both sides of the silicon steel sheet and do not contact the silicon steel.

[0136] 2) The length of the straight wire is consistent with the stack thickness and is equal to the translation distance of the even symmetric boundary condition.

[0137] 3) The end face of the straight conductor coincides with the plane where the boundary of the pair is located.

[0138] To further simplify the calculation, this embodiment adopts a method of setting up grid partitions, the characteristics of which are:

[0139] 1) Taking a certain length from the seam as the boundary (generally between 5-10mm), the silicon steel sheet where the seam is located and its upper and lower layers are divided into fine grid areas, and the silicon steel in other areas is the coarse grid area.

[0140] 2) The fine grid area in 1) above needs to have an intermediate layer, which can be done using the Mash Layers command.

[0141] 3) In the above 1), the maximum grid size of the fine grid area is set smaller than that of the coarse grid area. Generally, the maximum grid size of the fine grid area is 1 mm, and that of the coarse grid area is 2-3 mm.

[0142] like Fig. 9 As shown, the larger the number of stacks, the more accurate the calculation, but the number of grids increases linearly, and the single stack periodic model provided by this embodiment has the best calculation accuracy and efficiency (the fewer the number of grids, the higher the efficiency; in finite element simulation, when the calculation becomes more and more accurate, the calculation result gradually tends to a stable value.).

[0143] In this embodiment, the silicon steel sheet can be set to anisotropic or isotropic properties, which can be selected according to the researcher's own needs and hardware equipment conditions. The characteristics are:

[0144] 1) When set to anisotropy, two BH curves along the rolling direction and perpendicular to the rolling direction must be given during material setting.

[0145] 2) When set to anisotropy, the calculation accuracy is further improved, and at the same time, higher requirements are placed on the equipment.

[0146] 3) When set to anisotropy, when the silicon steel sheet is applied to the material, the material direction must be set according to the actual magnetic circuit direction to ensure that the magnetic circuit is always consistent with the high magnetic permeability direction of the material.

[0147] In summary, the transformer core no-load performance analysis method provided in this embodiment takes into account the influence of the step-by-step overlap method at the core joints, paint film thickness, material sheet thickness and gap size on the no-load performance of the transformer, thereby avoiding the problems of core no-load loss and no-load current design exceeding the standard.

[0148] Example 2

[0149] Based on the same inventive concept as Example 1, this embodiment also provides a transformer core no-load performance analysis system. Since the principle of solving the problem by this system is similar to the aforementioned transformer core no-load performance analysis method, the implementation of this system can refer to the implementation of the transformer core no-load performance analysis method.

[0150] like Figure 2 As shown, the transformer core no-load performance analysis system includes:

[0151] The first acquisition module 10 is used to acquire the hysteresis loss and eddy current loss of a single silicon steel sheet in the iron core.

[0152] The first determination module 20 is used to determine the loss of a single joint area of ​​the core according to the hysteresis loss and eddy current loss of a single silicon steel sheet in the core.

[0153] The second determination module 30 is used to determine the total loss of the core according to the loss of a single joint area of ​​the core.

[0154] The second acquisition module 40 is used to acquire the average magnetic field strength of the cross section of the silicon steel sheet.

[0155] The third determination module 50 is used to determine the no-load current of the core according to the average magnetic field strength of the silicon steel sheet cross section; and analyze the no-load performance of the transformer core according to the total loss of the core and the no-load current.

[0156] Exemplarily, the first determining module includes:

[0157] The first calculation unit is used to calculate the loss P of a single joint area of ​​the core according to the following formula 1 :

[0158]

[0159] Among them, k is the core lamination coefficient; h 1 is the core lamination height; n is the total number of silicon steel sheets in one step of the joint area; m is the number of silicon steel sheets in each stack; b 1 is the number of steps in the step-by-step overlap method of silicon steel sheets; h is the thickness of a single silicon steel sheet; P hi is the hysteresis loss of the i-th silicon steel sheet; P oi is the eddy current loss of the i-th silicon steel sheet.

[0160] Exemplarily, the second determining module includes:

[0161] The first acquisition unit is used to acquire the unit iron loss P' under the average magnetic flux density of the silicon steel sheet cross section.

[0162] The second calculation unit is used to calculate the total loss P of the core according to the following formula 总 :

[0163] P 总 =4P 1 +b·k·h 1 ·d·P'·ρ.

[0164] Among them, P 1 is the loss of a single joint area of ​​the core; b is the width of a single silicon steel sheet; k is the core lamination coefficient; h 1 is the height of the core laminations; d is the total length of the core column and yoke excluding the joints in the core; ρ is the density of the silicon steel sheet.

[0165] Exemplarily, the third determining module includes:

[0166] The second acquisition unit is used to obtain the excitation current I of a single joint area in the iron core. 1 And the number of turns N of the excitation wire.

[0167] The third calculation unit is used to calculate the no-load current I of the core according to the following formula:

[0168]

[0169] Among them, H' is the average magnetic field intensity of the silicon steel sheet cross section; d is the total length of the core column and yoke obtained by excluding the joints in the iron core.

[0170] For more specific working processes of the above modules, please refer to the corresponding contents disclosed in Example 1, which will not be repeated here.

[0171] Example 3

[0172] This embodiment provides a computer device, including a processor and a memory; wherein, when the processor executes the computer program stored in the memory, the steps of the transformer core no-load performance analysis method described in Example 1 are implemented.

[0173] For more specific details of the above method, please refer to the corresponding contents disclosed in Example 1, which will not be repeated here.

[0174] Example 4

[0175] This embodiment provides a computer-readable storage medium for storing a computer program; when the computer program is executed by a processor, the steps of the transformer core no-load performance analysis method described in Embodiment 1 are implemented.

[0176] For more specific details of the above method, please refer to the corresponding contents disclosed in Example 1, which will not be repeated here.

[0177] Example 5

[0178] This embodiment provides a computer program product, including computer executable instructions or a computer program. When the computer executable instructions or the computer program are executed by a processor, the steps of the transformer core no-load performance analysis method described in Example 1 are implemented.

[0179] For more specific details of the above method, please refer to the corresponding contents disclosed in Example 1, which will not be repeated here.

[0180] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the systems, devices, storage media, and computer program products disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the method part description.

[0181] Those skilled in the art can clearly understand that the technology in the embodiments of the present invention can be implemented by means of software plus a necessary general hardware platform. Based on this understanding, the technical solution in the embodiments of the present invention is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which can be stored in a storage medium such as ROM / RAM, a disk, an optical disk, etc., and includes a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment of the present invention or some parts of the embodiments.

[0182] In some embodiments, computer executable instructions may be in the form of a program, software, software module, script or code, written in any form of programming language (including compiled or interpreted languages, or declarative or procedural languages), and may be deployed in any form, including as a stand-alone program or as a module, component, subroutine or other unit suitable for use in a computing environment.

[0183] As an example, computer-executable instructions may, but need not, correspond to a file in a file system, may be stored as part of a file that stores other programs or data, such as in one or more scripts in a HyperText Markup Language (HTML) document, in a single file dedicated to the program in question, or in multiple coordinated files (e.g., files storing one or more modules, subroutines, or code portions).

[0184] As an example, computer executable instructions may be deployed to be executed on one electronic device, or on multiple electronic devices located at one site, or on multiple electronic devices distributed at multiple sites and interconnected by a communication network.

[0185] The present invention has been described in detail above in conjunction with specific implementations and exemplary examples, but these descriptions cannot be understood as limiting the present invention. Those skilled in the art understand that, without departing from the spirit and scope of the present invention, a variety of equivalent substitutions, modifications or improvements may be made to the technical solution of the present invention and its implementation methods, all of which fall within the scope of the present invention. The scope of protection of the present invention shall be subject to the attached claims.

Claims

1. A method for analyzing the no-load performance of transformer core, It is characterized in that include: Obtain the hysteresis loss and eddy current loss of a single silicon steel sheet in the iron core; According to the hysteresis loss and eddy current loss of a single silicon steel sheet in the core, the loss of a single joint area of ​​the core is determined; Determine the total loss of the core based on the loss of a single seam area of ​​the core; Obtain the average magnetic field strength of the silicon steel sheet cross section; The no-load current of the core is determined based on the average magnetic field strength of the silicon steel sheet cross section; the no-load performance of the transformer core is analyzed based on the total loss of the core and the no-load current.

2. The transformer core no-load performance analysis method according to claim 1, It is characterized in that Determining the loss of a single joint area of ​​the core according to the hysteresis loss and eddy current loss of a single silicon steel sheet in the core includes: The loss P of a single joint area of ​​the core is calculated according to the following formula 1 : Among them, k is the core lamination coefficient; h 1 is the core lamination height; n is the total number of silicon steel sheets in one step of the joint area; m is the number of silicon steel sheets in each stack; b 1 is the number of steps in the step-by-step overlap method of silicon steel sheets; h is the thickness of a single silicon steel sheet; P hi is the hysteresis loss of the i-th silicon steel sheet; P oi is the eddy current loss of the i-th silicon steel sheet.

3. The transformer core no-load performance analysis method according to claim 1, It is characterized in that Determining the total loss of the core according to the loss of a single joint area of ​​the core includes: Obtain the unit iron loss P' under the average magnetic flux density of the silicon steel sheet cross section; The total core loss P is calculated according to the following formula 总 : P 总 =4P 1 +b·k·h 1 ·d·P'·ρ; Among them, P 1 is the loss of a single joint area of ​​the core; b is the width of a single silicon steel sheet; k is the core lamination coefficient; h 1 is the height of the core laminations; d is the total length of the core column and yoke excluding the joints in the core; ρ is the density of the silicon steel sheet.

4. The transformer core no-load performance analysis method according to claim 1, It is characterized in that Determining the no-load current of the core according to the average magnetic field strength of the cross section of the silicon steel sheet includes: Get the excitation current I of a single joint area in the core 1 and the number of turns N of the excitation wire; Calculate the no-load current I of the core according to the following formula: Among them, H' is the average magnetic field intensity of the silicon steel sheet cross section; d is the total length of the core column and yoke obtained by excluding the joints in the iron core.

5. A transformer core no-load performance analysis system, It is characterized in that include: The first acquisition module is used to obtain the hysteresis loss and eddy current loss of a single silicon steel sheet in the iron core; The first determination module is used to determine the loss of a single joint area of ​​the core according to the hysteresis loss and eddy current loss of a single silicon steel sheet in the core; The second determination module is used to determine the total loss of the core according to the loss of a single joint area of ​​the core; The second acquisition module is used to obtain the average magnetic field strength of the cross section of the silicon steel sheet; The third determination module is used to determine the no-load current of the core according to the average magnetic field strength of the silicon steel sheet cross section; and analyze the no-load performance of the transformer core based on the total loss of the core and the no-load current.

6. The transformer core no-load performance analysis system according to claim 5, It is characterized in that The first determining module comprises: The first calculation unit is used to calculate the loss P of a single joint area of ​​the core according to the following formula 1 : Among them, k is the core lamination coefficient; h 1 is the core lamination height; n is the total number of silicon steel sheets in one step of the joint area; m is the number of silicon steel sheets in each stack; b 1 is the number of steps in the step-by-step overlap method of silicon steel sheets; h is the thickness of a single silicon steel sheet; P hi is the hysteresis loss of the i-th silicon steel sheet; P oi is the eddy current loss of the i-th silicon steel sheet.

7. The transformer core no-load performance analysis system according to claim 6, It is characterized in that The second determining module comprises: The first acquisition unit is used to acquire the unit iron loss P' under the average magnetic flux density of the silicon steel sheet cross section; The second calculation unit is used to calculate the total loss P of the core according to the following formula 总 : P 总 =4P 1 +b·k·h 1 ·d·P'·ρ; Among them, P 1 is the loss of a single joint area of ​​the core; b is the width of a single silicon steel sheet; k is the core lamination coefficient; h 1 is the height of the core laminations; d is the total length of the core column and yoke excluding the joints in the core; ρ is the density of the silicon steel sheet.

8. The transformer core no-load performance analysis system according to claim 5, It is characterized in that The third determination module comprises: The second acquisition unit is used to obtain the excitation current I of a single joint area in the iron core. 1 and the number of turns N of the excitation wire; The third calculation unit is used to calculate the no-load current I of the core according to the following formula: Among them, H' is the average magnetic field intensity of the silicon steel sheet cross section; d is the total length of the core column and yoke obtained by excluding the joints in the iron core.

9. A computer device, It is characterized in that It comprises a processor and a memory; wherein, when the processor executes the computer program stored in the memory, the steps of the transformer core no-load performance analysis method described in any one of claims 1 to 4 are implemented.

10. A computer-readable storage medium, It is characterized in that Used to store computer programs; when the computer programs are executed by the processor, the steps of the transformer core no-load performance analysis method described in any one of claims 1-4 are implemented.

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