Batch calculation method, device and equipment of main transformer short-circuit current and storage medium

Abstract

This invention provides a method, apparatus, device, and storage medium for batch calculation of short-circuit current of a main transformer. The method includes: acquiring the equivalent parameters of the system connected to the transformer and the rated parameters on the transformer equipment nameplate; selecting a reference capacity and a reference voltage as conversion references, and performing per-unit conversion on the equivalent parameters of the system connected to the transformer and the parameters on the transformer equipment nameplate according to the conversion references to obtain the conversion parameters required for calculating the transformer short-circuit current; determining transformer fault solution models under different test conditions, and inputting the conversion parameters into each transformer fault solution model to obtain main transformer short-circuit current data corresponding to different test conditions. This invention can conveniently and quickly realize batch processing of main transformer short-circuit current under multiple actual operating conditions.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power equipment evaluation, in particular to a method, device and equipment for batch calculation of short-circuit current of main transformer and a storage medium. BACKGROUND

[0002] The calculation of short-circuit current of running main transformer is an important link of checking the short-circuit current resistance of main transformer. The checking is based on the maximum short-circuit current that can be withstood by factors such as thermal stability and hardware dynamic strength of the device, and the maximum short-circuit current is compared with the maximum short-circuit current that can flow through the running main transformer to evaluate the running reliability.

[0003] There are two main techniques for solving the short-circuit current of running main transformer: one is actual short-circuit current calculation based on network structure or power flow data; the other is calculation through a typical transformer model. The former needs actual running data support and is usually used for online evaluation of real-time actual running data or pre-calculation of running data provided by network simulation; the latter is a method for solving the short-circuit current of running transformer through a classical transformer model without actual running sampling or network simulation.

[0004] The necessary condition for the above technical route one is actual running network structure and working condition data. It is difficult to access actual running data, and not all regional networks have simulation models that meet the actual situation for calculation. In this case, only technical route two can be adopted; but the current technical route two usually uses system voltage and system impedance provided by the national standard for calculation, which is completely out of touch with the actual running situation, resulting in that the calculation result is not referenceable and cannot be effectively used for main transformer running capacity evaluation. In addition, the running condition, fault position and fault type of main transformer all affect the short-circuit current result of technical route two. For the case of a large number of transformers in a large area, there is currently no method that can conveniently and quickly realize batch processing. SUMMARY

[0005] The present application aims to provide a method, device and equipment for batch calculation of short-circuit current of main transformer to solve the above technical problems, so as to conveniently and quickly realize batch processing of short-circuit current of main transformer under actual multiple running conditions.

[0006] In order to solve the above technical problems, the present application provides a method for batch calculation of short-circuit current of main transformer, comprising:

[0007] obtaining the equivalent parameters of the system connected to the transformer and the device nameplate parameters of the transformer;

[0008] The reference capacity and the reference voltage are selected as a conversion reference, and the equivalent parameters of a system connected with the transformer and the nameplate parameters of the transformer device are normalized according to the conversion reference, so that the conversion parameters required for calculating the short-circuit current of the transformer are obtained.

[0009] The transformer fault solving models under different to-be-tested working conditions are determined, the conversion parameters are input into each transformer fault solving model, and the main transformer short-circuit current data corresponding to different to-be-tested working conditions are obtained.

[0010] Further, the equivalent parameters of the system connected with the transformer include the system side voltage of the transformer, the high-voltage side system equivalent impedance and the medium-voltage side system equivalent impedance.

[0011] Further, the nameplate parameters of the transformer device include the main transformer capacity, the high-voltage side rated voltage, the medium-voltage side rated voltage, the low-voltage side rated voltage, the high-medium-short circuit impedance, the high-low-short circuit impedance and the medium-low-short circuit impedance.

[0012] Further, the conversion parameters required for calculating the short-circuit current of the transformer include the system side voltage normalization value, the high-voltage side system equivalent impedance normalization value, the medium-voltage side system equivalent impedance normalization value, the transformer high-voltage side impedance normalization value, the transformer medium-voltage side impedance normalization value and the transformer low-voltage side impedance normalization value.

[0013] Further, the different to-be-tested working conditions are determined based on the power supply situation, the operation mode and the fault condition of the transformer; wherein the fault condition includes the fault position and the fault type.

[0014] Further, the power supply situation of the transformer includes the high-voltage side power supply, the medium-voltage side power supply and the high-voltage side and medium-voltage side simultaneous power supply; the operation mode includes the whole independent operation, the whole parallel operation and the partial parallel operation; and the fault condition includes the high-voltage side three-phase fault, the high-voltage side single-phase fault, the medium-voltage side three-phase short circuit, the medium-voltage side single-phase short circuit and the low-voltage side three-phase short circuit.

[0015] The application further provides a main transformer short-circuit current batch calculation device, which comprises:

[0016] The parameter acquisition module is configured to acquire the equivalent parameters of a system connected with the transformer and the nameplate parameters of the transformer device.

[0017] The parameter conversion module is configured to select the reference capacity and the reference voltage as a conversion reference, and normalize the equivalent parameters of the system connected with the transformer and the nameplate parameters of the transformer device according to the conversion reference, so that the conversion parameters required for calculating the short-circuit current of the transformer are obtained.

[0018] A current calculation module is configured to determine transformer fault solving models under different to-be-tested operating conditions, input the conversion parameters into each transformer fault solving model, and obtain main transformer short-circuit current data corresponding to different to-be-tested operating conditions.

[0019] The embodiment of the present application also provides an electronic device, which comprises a processor and a memory storing a computer program, and the processor implements the main transformer short-circuit current batch calculation of any one of the embodiments when executing the computer program.

[0020] The embodiment of the present application also provides a non-transitory computer readable storage medium, which stores a computer program, and the computer program is executed by a processor to implement the main transformer short-circuit current batch calculation method of any one of the embodiments.

[0021] Compared with the prior art, the present application has the following beneficial effects:

[0022] The embodiment of the present application provides a main transformer short-circuit current batch calculation method, device, equipment and storage medium, and the method comprises the following steps: obtaining equivalent parameters of a system connected with a transformer and equipment nameplate parameters of the transformer; selecting a reference capacity and a reference voltage as a conversion reference, performing dimensionless conversion on the equivalent parameters of the system connected with the transformer and the equipment nameplate parameters of the transformer according to the conversion reference, and obtaining conversion parameters required for calculating the short-circuit current of the transformer; determining transformer fault solving models under different to-be-tested operating conditions, inputting the conversion parameters into each transformer fault solving model, and obtaining main transformer short-circuit current data corresponding to different to-be-tested operating conditions. The present application can conveniently and quickly realize batch processing of the main transformer short-circuit current under actual multiple operating conditions. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 is a flowchart of the main transformer short-circuit current batch calculation method provided by the embodiment of the present application;

[0024] Figure 2 is a structural schematic diagram of the main transformer short-circuit current batch calculation device provided by the embodiment of the present application. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0026] Please refer to Figure 1 The embodiment of the present application provides a main transformer short-circuit current batch calculation method, which can comprise the following steps:

[0027] S1. Obtain the equivalent parameters of the system connected to the transformer and the nameplate parameters of the transformer equipment;

[0028] S2. Select the reference capacity and reference voltage as the conversion reference, and perform per-unit conversion on the equivalent parameters of the system connected to the transformer and the nameplate parameters of the transformer equipment according to the conversion reference to obtain the conversion parameters required for calculating the short-circuit current of the transformer.

[0029] In this embodiment of the invention, the conversion parameters required for calculating the transformer short-circuit current further include the per-unit value of the system side voltage, the per-unit value of the equivalent impedance of the high-voltage side system, the per-unit value of the equivalent impedance of the medium-voltage side system, the per-unit value of the transformer high-voltage side impedance, the per-unit value of the transformer medium-voltage side impedance, and the per-unit value of the transformer low-voltage side impedance.

[0030] S3. Determine the transformer fault solution model under different test conditions, and input the converted parameters into each transformer fault solution model to obtain the main transformer short-circuit current data corresponding to different test conditions.

[0031] Step S3 is used to develop transformer fault solution models under different test conditions. The transformer fault model is open and expandable, and calculation factors such as transformer series equipment and neutral point series equipment can be added according to the actual situation.

[0032] In this embodiment of the invention, the equivalent parameters of the system to which the transformer is connected further include the system-side voltage, the equivalent impedance of the high-voltage side system, and the equivalent impedance of the medium-voltage side system to which the transformer is connected.

[0033] In this embodiment of the invention, the transformer equipment nameplate parameters further include main transformer capacity, high-voltage side rated voltage, medium-voltage side rated voltage, low-voltage side rated voltage, high-medium short-circuit impedance, high-low short-circuit impedance, and medium-low short-circuit impedance.

[0034] In this embodiment of the invention, the different test conditions are further determined based on the power supply status, operating mode, and fault conditions of the transformer; wherein, the fault conditions include the fault location and fault type.

[0035] In this embodiment of the invention, the power supply of the transformer further includes high-voltage side power supply, medium-voltage side power supply, and simultaneous power supply of high-voltage and medium-voltage sides; the operation mode includes all independent operation (separate operation), all parallel operation, and partial parallel operation; the fault conditions include high-voltage side three-phase fault, high-voltage side single-phase fault, medium-voltage side three-phase short circuit, medium-voltage side single-phase short circuit, and low-voltage side three-phase short circuit.

[0036] Based on the above scheme, and to facilitate a better understanding of the batch calculation method for main transformer short-circuit current provided in the embodiments of the present invention, the following detailed description is provided:

[0037] This invention, by taking into account the operating conditions, fault location, and fault type of the main transformer, develops a batch calculation method for the short-circuit current flowing through the operating main transformer based on the transformer equivalent model and the equivalent voltage and equivalent impedance of the actual system. Specifically, it may include the following steps:

[0038] S1, Define the system-side voltage U S Equivalent impedance Z of the high-voltage side system SH Equivalent impedance Z of medium-voltage side system SM .

[0039] S2: Obtain information from the transformer nameplate: Main transformer capacity S T (MVA), rated voltage U on the high-voltage side NH (kV), Rated voltage U on the medium voltage side NM (kV), Low-voltage side rated voltage U NL (kV), High-medium short-circuit impedance Uk H-M (%), High-low short-circuit impedance Uk H-L (%), Medium-low short-circuit impedance Uk M-L (%).

[0040] S3: Apply the above parameters to the same baseline capacity S N , with the rated voltage U on the high-voltage side NH The reference voltage is converted to a per-unit value, and the resulting parameter U is obtained. S *、Z SH *、Z SM *、Z HM *、Z HL *、Z ML *. Based on Z HM *、Z HL *、Z ML *Calculate the impedances of the high, medium, and low voltage sides of the transformer, respectively, as Z. H *、Z M *、Z L *

[0041] S4: Based on the transformer neutral point grounding situation and the actual system operation, consider three operating scenarios under the fully independent operation (separate operation) mode: power supply only to the high-voltage side, power supply to the high-medium-high voltage side simultaneously, and power supply only to the medium-voltage side.

[0042] Based on the above three operating conditions, only five fault scenarios need to be considered: high-voltage side three-phase fault (with power supply to the medium-voltage side), high-voltage side single-phase fault (with power supply to the medium-voltage side), medium-voltage side three-phase short circuit (with power supply to the high-voltage side), medium-voltage side single-phase short circuit (with power supply to the high-voltage side), and low-voltage side three-phase short circuit (with power supply to either the high-voltage or medium-voltage side) (a total of 11 fault scenarios).

[0043] S5: Operating Condition 1: High and medium voltage side power supply, low voltage side three-phase short circuit:

[0044] Calculate the equivalent short-circuit impedance Z* of the main transformer and the short-circuit current I* of the equivalent network under operating condition 1 based on the impedance network diagram considering the equivalent impedance of the system:

[0045]

[0046]

[0047] Based on the short-circuit current I* of the equivalent network, the short-circuit currents flowing through the branches on the high-voltage side, medium-voltage side, and low-voltage side are calculated respectively.

[0048]

[0049]

[0050]

[0051] The calculated per-unit value Once converted to a valid value, it can be used for transformer performance evaluation.

[0052] S6: Operating Condition 2: High-voltage side power supply only, three-phase short circuit on medium-voltage side:

[0053] Calculate the equivalent short-circuit impedance Z* of the main transformer and the short-circuit current I* of the equivalent network under operating condition 2 based on the impedance network diagram considering the equivalent impedance of the system:

[0054]

[0055]

[0056] The short-circuit currents I* flowing through the high-voltage and medium-voltage branches are calculated based on the short-circuit currents on the equivalent network.

[0057]

[0058] The calculated per-unit value Once converted to a valid value, it can be used for transformer performance evaluation.

[0059] S7: Operating Condition 3: High-voltage side power supply only, three-phase short circuit on low-voltage side:

[0060] Calculate the equivalent short-circuit impedance Z* of the main transformer and the short-circuit current I* of the equivalent network under operating condition 3 based on the impedance network diagram considering the equivalent impedance of the system:

[0061]

[0062]

[0063] The short-circuit currents I* flowing through the high-voltage and low-voltage branches are calculated based on the short-circuit currents on the equivalent network.

[0064]

[0065] The calculated per-unit value Once converted to a valid value, it can be used for transformer performance evaluation.

[0066] S8: Operating Condition 4: High-voltage side power supply only, medium-voltage side single-phase short circuit:

[0067] A single-phase ground fault on the medium-voltage side is an asymmetrical ground fault, therefore the sequence network method is required for short-circuit current calculation. Based on a composite sequence network constructed by connecting positive-sequence, negative-sequence, and zero-sequence equivalent networks in series, the current I* of the composite sequence network is calculated.

[0068]

[0069] Calculate the positive, negative, and zero-sequence currents on the high-voltage side as follows: Calculate the positive, negative, and zero-sequence currents on the medium-voltage side as follows:

[0070]

[0071]

[0072]

[0073] Based on the above calculations of the positive, negative, and zero-sequence currents of the high-voltage and medium-voltage branches, calculate the short-circuit currents flowing through the high-voltage and medium-voltage branches. The calculated per-unit value Once converted to a valid value, it can be used for transformer performance evaluation.

[0074] S9: Operating Condition 5: Medium-voltage side power supply only, low-voltage side three-phase short circuit:

[0075] Calculate the equivalent short-circuit impedance Z* of the main transformer and the short-circuit current I* of the equivalent network under operating condition 5 based on the impedance network diagram considering the equivalent impedance of the system:

[0076]

[0077]

[0078] The short-circuit currents I* flowing through the high-voltage and low-voltage branches are calculated based on the short-circuit currents on the equivalent network.

[0079]

[0080] The calculated per-unit value Once converted to a valid value, it can be used for transformer performance evaluation.

[0081] S10: Operating Condition 6: Medium-voltage side power supply only, high-voltage side three-phase short circuit:

[0082] Calculate the equivalent short-circuit impedance Z* of the main transformer and the short-circuit current I* of the equivalent network under operating condition 6 based on the impedance network diagram considering the equivalent impedance of the system:

[0083]

[0084]

[0085] The short-circuit currents I* flowing through the high-voltage and medium-voltage branches are calculated based on the short-circuit currents on the equivalent network.

[0086]

[0087] The calculated per-unit value Once converted to a valid value, it can be used for transformer performance evaluation.

[0088] S11: Operating Condition 7: High and medium voltage side power supply, three-phase short circuit on the medium voltage side:

[0089] The equivalent network for condition 7 is the same as that for condition 2.

[0090] S12: Operating Condition 8: High and medium voltage side power supply, high voltage side three-phase short circuit:

[0091] The equivalent network for operating condition 8 is the same as that for operating condition 6.

[0092] S13: Operating Condition 9: High and medium voltage side power supply, single-phase short circuit on the high voltage side:

[0093] The single-phase ground fault on the high-voltage side is an asymmetrical ground fault. The calculation approach is the same as for operating condition 4, using the sequence network method to calculate the short-circuit current. Based on a composite sequence network composed of positive-sequence, negative-sequence, and zero-sequence equivalent networks connected in series, the current I* of the composite sequence network is calculated.

[0094]

[0095] Calculate the positive, negative, and zero-sequence currents on the high-voltage side as follows: Calculate the positive, negative, and zero-sequence currents on the medium-voltage side as follows:

[0096]

[0097]

[0098]

[0099] Based on the above calculations of the positive, negative, and zero-sequence currents of the high-voltage and medium-voltage branches, calculate the short-circuit currents flowing through the high-voltage and medium-voltage branches. The calculated per-unit value Once converted to a valid value, it can be used for transformer performance evaluation.

[0100] S14: Operating Condition 10: Medium-voltage side power supply only, single-phase short circuit on high-voltage side:

[0101] The equivalent network for operating condition 10 is the same as that for operating condition 9.

[0102] S15: Operating Condition 11: High and medium voltage side power supply, medium voltage side single-phase short circuit:

[0103] The equivalent network for operating condition 11 is the same as that for operating condition 4.

[0104] It should be noted that, based on the general calculation formula for the above operating conditions, a rapid batch calculation model can be established. The model only needs to input or import the parameters of S1 to S3 to automatically generate the short-circuit currents on each side of the transformer for a total of 11 possible operating conditions in reality, from S5 to S15, which can be used for evaluation in the verification of the short-circuit withstand capability of the main transformer.

[0105] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0106] (1) A batch calculation method is proposed that can calculate the short-circuit current flowing through the main transformer branch under different operating conditions and different fault conditions.

[0107] (2) Instead of adopting the recommended values ​​of the national standard, the system side equivalent voltage and equivalent impedance are calculated by equating the actual power grid operation to the short-circuit current flowing through the main transformer.

[0108] (3) Formulas are given for calculating the short-circuit current flowing through the main transformer branch under the conditions of high-voltage side power supply, medium-voltage side power supply, and simultaneous high-medium-voltage side power supply;

[0109] (4) Give the formula for calculating the short-circuit current flowing through the main transformer branch under the conditions of single-phase grounding fault and three-phase fault at the transformer port;

[0110] (5) Based on the derived formula, a rapid batch calculation tool is made. The short-circuit current of the branch flowing through the main transformer under the current operating conditions can be directly obtained by filling in the basic information of the system side and the transformer nameplate information according to the actual situation. This tool is used for the verification of the transformer's short-circuit withstand capability.

[0111] It should be noted that, for the sake of simplicity, the above methods or process embodiments are all described as a series of actions. However, those skilled in the art should understand that the embodiments of the present invention are not limited to the described order of actions, because according to the embodiments of the present invention, some steps can be performed in other orders or simultaneously. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are all optional embodiments, and the actions involved are not necessarily essential to the embodiments of the present invention.

[0112] Please see Figure 2 This invention also provides a device for batch calculation of short-circuit current of a main transformer, comprising:

[0113] Parameter acquisition module 1 is used to acquire the equivalent parameters of the system connected to the transformer and the parameters on the transformer equipment nameplate;

[0114] The parameter conversion module 2 is used to select the reference capacity and reference voltage as the conversion reference, and to convert the equivalent parameters of the system connected to the transformer and the nameplate parameters of the transformer equipment according to the conversion reference to obtain the conversion parameters required for the short-circuit current calculation of the transformer.

[0115] The current calculation module 3 is used to determine the transformer fault solution model under different test conditions, and input the conversion parameters into each transformer fault solution model to obtain the main transformer short-circuit current data corresponding to different test conditions.

[0116] Furthermore, the equivalent parameters of the system to which the transformer is connected include the system-side voltage, the equivalent impedance of the high-voltage side system, and the equivalent impedance of the medium-voltage side system to which the transformer is connected.

[0117] Furthermore, the transformer equipment nameplate parameters include main transformer capacity, high-voltage side rated voltage, medium-voltage side rated voltage, low-voltage side rated voltage, high-medium short-circuit impedance, high-low short-circuit impedance, and medium-low short-circuit impedance.

[0118] Furthermore, the conversion parameters required for calculating the transformer short-circuit current include the per-unit values ​​of the system side voltage, the per-unit values ​​of the equivalent impedance of the high-voltage side system, the per-unit values ​​of the equivalent impedance of the medium-voltage side system, the per-unit values ​​of the transformer high-voltage side impedance, the per-unit values ​​of the transformer medium-voltage side impedance, and the per-unit values ​​of the transformer low-voltage side impedance.

[0119] Furthermore, the different test conditions are determined based on the transformer's power supply status, operating mode, and fault conditions; wherein, the fault conditions are determined based on the fault location and fault type.

[0120] Furthermore, the power supply conditions of the transformer include high-voltage side power supply, medium-voltage side power supply, and simultaneous power supply to both high-voltage and medium-voltage sides; the operating modes include fully independent operation, fully parallel operation, and partially parallel operation; the fault conditions include three-phase fault on the high-voltage side, single-phase fault on the high-voltage side, three-phase short circuit on the medium-voltage side, single-phase short circuit on the medium-voltage side, and three-phase short circuit on the low-voltage side.

[0121] It is understood that the above-described device embodiments correspond to the method embodiments of the present invention. The main transformer short-circuit current batch calculation device provided by the embodiments of the present invention can realize the main transformer short-circuit current batch calculation method provided by any one of the method embodiments of the present invention.

[0122] The present invention also provides an electronic device, including a processor and a memory storing a computer program, wherein the processor executes the computer program to implement the batch calculation method for short-circuit current of the main transformer as described in any one of the claims.

[0123] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the batch calculation method for the short-circuit current of the main transformer as described in any one of the claims.

[0124] It should be noted that the device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Furthermore, in the accompanying drawings of the device embodiments provided by this invention, the connection relationships between modules indicate that they have communication connections, which can be specifically implemented as one or more communication buses or signal lines. Those skilled in the art can understand and implement this without any creative effort.

[0125] Those skilled in the art will clearly understand that, for convenience and simplicity, the specific working process of the device described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0126] The terminal device can be a desktop computer, laptop, handheld computer, or cloud server, etc. The terminal device may include, but is not limited to, a processor and a memory.

[0127] The processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor can be a microprocessor or any conventional processor. The processor is the control center of the terminal device, connecting all parts of the terminal device via various interfaces and lines.

[0128] The memory can be used to store the computer program. The processor implements various functions of the terminal device by running or executing the computer program stored in the memory and calling data stored in the memory. The memory may mainly include a program storage area and a data storage area. The program storage area may store the operating system, at least one application program required for a function, etc.; the data storage area may store data created based on the use of the mobile phone, etc. In addition, the memory may include high-speed random access memory, and may also include non-volatile memory, such as hard disk, RAM, plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, at least one disk storage device, flash memory device, or other volatile solid-state storage device.

[0129] The storage medium is a computer-readable storage medium, and the computer program is stored in the computer-readable storage medium. When executed by a processor, the computer program can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable file, or some intermediate form. The computer-readable medium can include: any entity or device capable of carrying the computer program code, recording media, USB flash drive, portable hard drive, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc. It should be noted that the content included in the computer-readable medium can be appropriately added or removed according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, the computer-readable medium does not include electrical carrier signals and telecommunication signals.

[0130] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A method for batch calculation of short circuit current of a main transformer, characterized in that, The method comprises the following steps: obtaining equivalent parameters of a system connected with a transformer and parameters on a nameplate of the transformer; selecting a reference capacity and a reference voltage as a conversion reference, and performing per-unit conversion on the equivalent parameters of the system connected with the transformer and the parameters on the nameplate of the transformer according to the conversion reference, to obtain conversion parameters required for calculation of a short-circuit current of the transformer; the conversion parameters required for calculation of the short-circuit current of the transformer include a per-unit system-side voltage, a per-unit high-voltage-side system equivalent impedance, a per-unit medium-voltage-side system equivalent impedance, a per-unit high-voltage-side transformer impedance, a per-unit medium-voltage-side transformer impedance, and a per-unit low-voltage-side transformer impedance; determining transformer fault solving models under different to-be-tested working conditions, inputting the conversion parameters into each transformer fault solving model, and obtaining main transformer short-circuit current data corresponding to the different to-be-tested working conditions; the different to-be-tested working conditions are determined based on power supply conditions, operation modes, and fault conditions of the transformer; the fault conditions are determined based on fault positions and fault types; the power supply conditions of the transformer include high-voltage-side power supply, medium-voltage-side power supply, and high-voltage-side and medium-voltage-side simultaneous power supply; the operation modes include all independent operation, all parallel operation, and partial parallel operation; and the fault conditions include high-voltage-side three-phase fault, high-voltage-side single-phase fault, medium-voltage-side three-phase short circuit, medium-voltage-side single-phase short circuit, and low-voltage-side three-phase short circuit.

2. The method of claim 1, wherein, The equivalent parameters of the system connected with the transformer include a system-side voltage, a high-voltage-side system equivalent impedance, and a medium-voltage-side system equivalent impedance.

3. The method of claim 1, wherein, The parameters on the nameplate of the transformer include a main transformer capacity, a high-voltage-side rated voltage, a medium-voltage-side rated voltage, a low-voltage-side rated voltage, a high-medium-short-circuit impedance, a high-low-short-circuit impedance, and a medium-low-short-circuit impedance.

4. A main short circuit current bulk calculation device characterized by, The method comprises the following steps: a parameter obtaining module, configured to obtain a reference capacity and a reference voltage, equivalent parameters of a system connected with a transformer, and parameters on a nameplate of the transformer; a parameter conversion module, configured to take the reference capacity and the reference voltage as a conversion reference, and perform per-unit conversion on the equivalent parameters of the system connected with the transformer and the parameters on the nameplate of the transformer, to obtain conversion parameters required for calculation of a short-circuit current of the transformer; the conversion parameters required for calculation of the short-circuit current of the transformer include a per-unit system-side voltage, a per-unit high-voltage-side system equivalent impedance, a per-unit medium-voltage-side system equivalent impedance, a per-unit high-voltage-side transformer impedance, a per-unit medium-voltage-side transformer impedance, and a per-unit low-voltage-side transformer impedance; The current calculation module is configured to determine transformer fault solving models under different to-be-tested working conditions, input the conversion parameters into each transformer fault solving model, and obtain main transformer short-circuit current data corresponding to different to-be-tested working conditions; the different to-be-tested working conditions are determined based on power supply conditions, operation modes and fault conditions of the transformer; the fault conditions are determined based on fault positions and fault types; the power supply conditions of the transformer include high-voltage side power supply, medium-voltage side power supply and high-voltage side and medium-voltage side power supply; the operation modes include all independent operation, all parallel operation and partial parallel operation; and the fault conditions include high-voltage side three-phase fault, high-voltage side single-phase fault, medium-voltage side three-phase short circuit, medium-voltage side single-phase short circuit and low-voltage side three-phase short circuit.

5. The main short circuit current batch calculation device according to claim 4, characterized by The equivalent parameters of the system connected to the transformer include a system side voltage connected to the transformer, high-voltage side system equivalent impedance and medium-voltage side system equivalent impedance.

6. An electronic device comprising a processor and a memory having a computer program stored therein, characterized in that The processor executes the computer program to implement the main transformer short-circuit current batch calculation method of any one of claims 1 to 3. 7.A non-transitory computer-readable storage medium having stored thereon a computer program. The computer program is executed by the processor to implement the main transformer short-circuit current batch calculation method of any one of claims 1 to 3.

Images