A transformer three-phase calculation method and device based on matrix dimension reduction

Abstract

The present invention discloses a three-phase calculation method, device and storage medium for a transformer based on matrix dimensionality reduction. Among them, the method includes: calculating the resistance value and reactance value of a three-phase transformer according to the nameplate information of the three-phase transformer; calculating the first turns ratio on the primary side of the three-phase transformer and the second turns ratio on the secondary side of the three-phase transformer according to the tap position and rated voltage of the three-phase transformer; determining the full matrix of the three-phase transformer based on the resistance value, reactance value, first turns ratio and second turns ratio of the three-phase transformer; performing dimensionality reduction processing on the full matrix of the three-phase transformer according to a preset matrix dimensionality reduction rule to obtain a dimensionality reduction matrix of the three-phase transformer; and superimposing the dimensionality reduction matrix of the three-phase transformer into the system matrix for three-phase calculation to perform three-phase power flow calculation and determine the three-phase power flow result of the three-phase transformer. The present invention can retain the physical meaning of transformer variables during the process of order reduction, which is beneficial to calculating various variables of the transformer, and at the same time reduces the amount of calculation.

Description

Technical Field

[0001] The present invention relates to the technical field of distribution network construction simulation, and more specifically, to a three-phase calculation method and device for transformers based on matrix dimensionality reduction. Background Art

[0002] In current power grids with voltage levels of 220 kV and above, it is considered that the parameters and loads of the network are completely symmetric, so most power companies use single-phase calculation programs for network analysis. Due to reasons such as environmental, transmission corridor, and construction cost limitations, the number of non-transposed double-circuit lines on the same pole (less than 100 km) in urban power grids is increasing. The error of the reactive power of non-transposed double-circuit lines on the same pole obtained by using a single-phase calculation program greatly exceeds the allowable range. The actual situation of the distribution network is more complex, and there are cases of lines on the same pole. Previously, this situation was generally calculated using electromagnetic transient simulation programs, which caused difficulties for the digital twin of the distribution network. There is an urgent need to develop a three-phase digital twin calculation tool.

[0003] During the three-phase digital twin calculation process, a three-phase model of power system components is required. Due to different connection methods of transformers, the matrices in three-phase calculations are also different, and generally, the wiring group is used to represent. The wiring group of a transformer is a representation method of the combined wiring form of the primary winding and the secondary winding of the transformer. The wiring group of the transformer is very flexible, and different wiring methods are often used for the primary and secondary windings. Therefore, the three-phase matrix of the transformer is very complex, and different matrices need to be generated according to the wiring method, which brings trouble to three-phase power flow and transient calculations.

[0004] Common transformer wiring methods include delta and star connections. At the same time, the neutral point of the star connection has methods such as direct grounding, non-grounding, and grounding through an arc suppression coil. Considering the different wiring positions of the primary winding and the secondary winding of the transformer, a certain angle difference can be formed. These constitute all the elements of the transformer wiring group. The traditional transformer model uses matrix multiplication for three-phase calculations, which increases the calculation amount. At the same time, the physical meaning of the transformer variables is lost during the matrix multiplication process, which is not conducive to subsequent processing.

[0005] Aiming at the technical problems in the existing technology described above, such as the large calculation amount of three-phase transformer calculations and the loss of the physical meaning of transformer variables during matrix multiplication, no effective solution has been proposed yet. Summary of the Invention

[0006] Aiming at the technical problems in the existing technology, such as the large calculation amount of three-phase transformer calculations and the loss of the physical meaning of transformer variables during matrix multiplication, the present invention provides a three-phase calculation method and device for transformers based on matrix dimensionality reduction.

[0007] According to one aspect of the present invention, there is provided a three-phase calculation method for a transformer based on matrix dimensionality reduction, including:

[0008] Calculating the resistance value and reactance value of the three-phase transformer according to the nameplate information of the three-phase transformer; calculating the first transformation ratio of the primary side of the three-phase transformer and the second transformation ratio of the secondary side of the three-phase transformer according to the tap position and rated voltage of the three-phase transformer;

[0009] Determining the full matrix of the three-phase transformer based on the resistance value, reactance value, first transformation ratio and second transformation ratio of the three-phase transformer;

[0010] Performing dimensionality reduction processing on the full matrix of the three-phase transformer according to the preset matrix dimensionality reduction rule to obtain the dimensionality reduction matrix of the three-phase transformer;

[0011] Superimposing the dimensionality reduction matrix of the three-phase transformer into the system matrix for three-phase calculation to perform three-phase power flow calculation and determine the three-phase power flow result of the three-phase transformer.

[0012] Calculating the resistance value and reactance value of the three-phase transformer according to the nameplate information of the three-phase transformer, including:

[0013] Calculating the resistance value of the three-phase transformer according to the nameplate information of the three-phase transformer and using the following formula and the reactance value :

[0014]

[0015] wherein, is the resistance value of the three-phase transformer, is the reactance value of the three-phase transformer, is the rated capacity of the three-phase transformer, is the rated voltage of the three-phase transformer, is the short-circuit loss, is the percentage of impedance voltage.

[0016] Calculating the first transformation ratio of the primary side of the three-phase transformer and the second transformation ratio of the secondary side of the three-phase transformer according to the tap position and rated voltage of the three-phase transformer, including:

[0017] Calculating the first transformation ratio of the primary side of the three-phase transformer according to the tap position and rated voltage of the three-phase transformer and using the following formula and the second transformation ratio of the secondary side of the three-phase transformer :

[0018]

[0019] wherein, is the tap position of the primary side of the three-phase transformer, is the tap position on the secondary side of the three-phase transformer, is the rated voltage on the primary side of the three-phase transformer, is the rated voltage on the secondary side of the three-phase transformer.

[0020] Optionally, based on the resistance value, reactance value, first turns ratio, and second turns ratio of the three-phase transformer, determine the full matrix of the three-phase transformer, including:

[0021] Treat the three-phase transformer as three single-phase transformers, and based on the resistance value, reactance value, first turns ratio, and second turns ratio of the three-phase transformer, determine the single-phase matrix of each single-phase transformer;

[0022] Based on the single-phase matrices of the three single-phase transformers, determine the full matrix of the three-phase transformer.

[0023] Optionally, based on the resistance value, reactance value, first turns ratio, and second turns ratio of the three-phase transformer, determine the single-phase matrix of each single-phase transformer as:

[0024]

[0025] And, based on the single-phase matrices of the three single-phase transformers, determine the full matrix of the three-phase transformer as:

[0026]

[0027] Among them, the elements in the matrix , element , element , element , element , element , is the resistance value of the three-phase transformer, is the reactance value of the three-phase transformer, is the first turns ratio on the primary side of the three-phase transformer, is the second turns ratio on the secondary side of the three-phase transformer; i represents the primary side of the three-phase transformer, j represents the secondary side of the three-phase transformer; ia / ja / ix / jx are the 4 ports of phase A of the three-phase transformer respectively, ib / jb / iy / jy are the 4 ports of phase B of the three-phase transformer, ic / jc / iz / jz are the 4 ports of phase C of the three-phase transformer.

[0028] Optionally, according to the preset matrix dimensionality reduction rule, perform dimensionality reduction processing on the full matrix of the three-phase transformer to obtain the dimensionality reduction matrix of the three-phase transformer, including:

[0029] According to the wiring method on the primary side of the three-phase transformer, perform matrix dimensionality reduction on the primary side of the full matrix of the three-phase transformer;

[0030] According to the wiring mode of the secondary side of the three-phase transformer, perform matrix reduction on the secondary side for the matrix reduction obtained after reducing the dimension of the primary side matrix, so as to obtain the reduced-dimension matrix of the three-phase transformer.

[0031] Optionally, according to the wiring mode of the primary side of the three-phase transformer, perform matrix reduction on the full matrix of the three-phase transformer for the primary side, including:

[0032] Determine the wiring mode of the primary side of the three-phase transformer;

[0033] When the wiring mode of the primary side of the three-phase transformer is star connection and the neutral point is grounded, in the full matrix of the three-phase transformer, ix 、 iy and iz All columns are eliminated;

[0034] When the wiring mode of the primary side of the three-phase transformer is star connection, in the full matrix of the three-phase transformer, iy and iz Columns are merged into ix Column;

[0035] When the wiring mode of the primary side of the three-phase transformer is delta connection, and when the primary side line voltage phasor points to the 12 o'clock position of the clock as the minute hand and the secondary side line voltage phasor is at the 11 o'clock position of the clock, in the full matrix of the three-phase transformer, ix Column is merged into ic Column, iy Column is merged into ia Column and iz Column is merged into ib Column;

[0036] When the wiring mode of the primary side of the three-phase transformer is delta connection, and when the primary side line voltage phasor points to the 12 o'clock position of the clock as the minute hand and the secondary side line voltage phasor is at the 1 o'clock position of the clock, in the full matrix of the three-phase transformer, ix Column is merged into ib Column, iy Column is merged into ic Column and iz Column is merged into ia Column.

[0037] Optionally, according to the wiring mode of the secondary side of the three-phase transformer, perform matrix reduction on the matrix reduction obtained after reducing the dimension of the primary side matrix for the secondary side, so as to obtain the reduced-dimension matrix of the three-phase transformer, including:

[0038] Determine the wiring mode of the secondary side of the three-phase transformer;

[0039] When the wiring method on the secondary side of a three-phase transformer is a star connection with the neutral point grounded, the ix , iy and iz columns are all eliminated to obtain the reduced-dimension matrix of the three-phase transformer;

[0040] When the wiring method on the secondary side of a three-phase transformer is a star connection, the iy and iz columns are merged into the ix column to obtain the reduced-dimension matrix of the three-phase transformer;

[0041] When the wiring method on the secondary side of a three-phase transformer is a delta connection, and when the primary-side line voltage phasor points to the 12 o'clock position on the clock as the minute hand and the secondary-side line voltage phasor is at the 11 o'clock position on the clock, the ix column is merged into the ic column, the iy column is merged into the ia column, and the iz column is merged into the ib column to obtain the reduced-dimension matrix of the three-phase transformer;

[0042] When the wiring method on the secondary side of a three-phase transformer is a delta connection, and when the primary-side line voltage phasor points to the 12 o'clock position on the clock as the minute hand and the secondary-side line voltage phasor is at the 1 o'clock position on the clock, the ix column is merged into the ib column, the iy column is merged into the ic column, and the iz column is merged into the ia column to obtain the reduced-dimension matrix of the three-phase transformer.

[0043] The obtained reduced-dimension matrix of the three-phase transformer is:

[0044]

[0045] Among them, i represents the primary side of the three-phase transformer, and j represents the secondary side of the three-phase transformer; ia / ja are the two ports of phase A of the three-phase transformer, ib / jb are the two ports of phase B of the three-phase transformer, ic / jc are the two ports of phase C of the three-phase transformer; each element in the reduced-dimension matrix Elements obtained after eliminating or combining the elements in each column of the full matrix of a three-phase transformer according to a preset matrix dimensionality reduction rule.

[0046] Optionally, superimpose the dimensionality reduction matrix of the three-phase transformer onto the system matrix for three-phase calculation to perform three-phase power flow calculation, and determine the three-phase power flow results of the three-phase transformer, including:

[0047] Superimpose the dimensionality reduction matrix of the three-phase transformer onto the system matrix for three-phase calculation to perform three-phase power flow calculation, and obtain the voltages of each node in the system, where each port of the three-phase transformer is regarded as a node of the system;

[0048] Based on the dimensionality reduction matrix of the three-phase transformer and the voltages of each port of the three-phase transformer, calculate the current of the three-phase transformer using the following formula:

[0049]

[0050] Where, Represents the dimensionality reduction matrix of the three-phase transformer, Represents the voltages of each port of the three-phase transformer;

[0051] Based on the voltages and currents of each port of the three-phase transformer, calculate the power of the three-phase transformer using the following formula:

[0052]

[0053] Where, Represents the voltages of each port of the three-phase transformer, Represents conjugate;

[0054] Represents the currents of each port of the three-phase transformer.

[0055] According to another aspect of the present invention, there is provided a three-phase calculation device for a transformer based on matrix dimensionality reduction, including:

[0056] A calculation module, configured to calculate the resistance value and reactance value of the three-phase transformer according to the nameplate information of the three-phase transformer; calculate the first turns ratio of the primary side of the three-phase transformer and the second turns ratio of the secondary side of the three-phase transformer according to the tap position and rated voltage of the three-phase transformer;

[0057] A full matrix determination module, configured to determine the full matrix of the three-phase transformer based on the resistance value, reactance value, first turns ratio, and second turns ratio of the three-phase transformer;

[0058] A dimensionality reduction matrix determination module, configured to perform dimensionality reduction processing on the full matrix of the three-phase transformer according to a preset matrix dimensionality reduction rule to obtain the dimensionality reduction matrix of the three-phase transformer;

[0059] Three-phase power flow result determination module, which is used to superimpose the dimensionality reduction matrix of a three-phase transformer into the system matrix for three-phase calculation to determine the three-phase power flow results of the three-phase transformer.

[0060] Optionally, the calculation module is specifically used for:

[0061] According to the nameplate information of the three-phase transformer and using the following formula, calculate the resistance value of the three-phase transformer and the reactance value :

[0062]

[0063] In the formula, is the resistance value of the three-phase transformer, is the reactance value of the three-phase transformer, is the rated capacity of the three-phase transformer, is the rated voltage of the three-phase transformer, is the short-circuit loss, is the percentage of impedance voltage.

[0064] Optionally, the calculation module is specifically used for:

[0065] According to the tap position and rated voltage of the three-phase transformer, use the following formula to calculate the first transformation ratio on the primary side of the three-phase transformer and the second transformation ratio on the secondary side of the three-phase transformer :

[0066]

[0067] In the formula, is the tap position on the primary side of the three-phase transformer, is the tap position on the secondary side of the three-phase transformer, is the rated voltage on the primary side of the three-phase transformer, is the rated voltage on the secondary side of the three-phase transformer.

[0068] Optionally, the full matrix determination module is specifically used for:

[0069] Treat the three-phase transformer as three single-phase transformers, and based on the resistance value, reactance value, first transformation ratio and second transformation ratio of the three-phase transformer, determine the single-phase matrix of each single-phase transformer;

[0070] Based on the single-phase matrices of the three single-phase transformers, determine the full matrix of the three-phase transformer.

[0071] Optionally, the dimensionality reduction matrix determination module is specifically used for:

[0072] According to the wiring mode of the primary side of the three-phase transformer, perform matrix dimensionality reduction on the primary side of the full matrix of the three-phase transformer;

[0073] According to the wiring mode of the secondary side of the three-phase transformer, perform matrix dimensionality reduction on the matrix obtained after dimensionality reduction on the primary side matrix to obtain the dimensionality reduction matrix of the three-phase transformer.

[0074] Optionally, the dimensionality reduction matrix determination module is further specifically configured to:

[0075] Determine the wiring mode of the primary side of the three-phase transformer;

[0076] When the wiring mode of the primary side of the three-phase transformer is star connection and the neutral point is grounded, in the full matrix of the three-phase transformer ix 、 iy and iz All columns are eliminated;

[0077] When the wiring mode of the primary side of the three-phase transformer is star connection, in the full matrix of the three-phase transformer iy and iz Columns are merged into ix Column;

[0078] When the wiring mode of the primary side of the three-phase transformer is delta connection, and when the primary side line voltage phasor points to the 12 o'clock position of the clock as the minute hand, and the secondary side line voltage phasor is at the 11 o'clock position of the clock, in the full matrix of the three-phase transformer ix Columns are merged into ic Column, iy Columns are merged into ia Column and iz Columns are merged into ib Column;

[0079] When the wiring mode of the primary side of the three-phase transformer is delta connection, and when the primary side line voltage phasor points to the 12 o'clock position of the clock as the minute hand, and the secondary side line voltage phasor is at the 1 o'clock position of the clock, in the full matrix of the three-phase transformer ix Columns are merged into ib Column, iy Columns are merged into ic Column and iz Columns are merged into ia Column.

[0080] Optionally, the dimensionality reduction matrix determination module is further specifically configured to:

[0081] Determine the wiring mode of the secondary side of the three-phase transformer;

[0082] When the wiring method on the secondary side of the three-phase transformer is star connection and the neutral point is grounded, in the matrix reduction obtained by reducing the dimension of the primary side matrix, ix and iy and iz all columns are eliminated to obtain the reduced-dimension matrix of the three-phase transformer;

[0083] When the wiring method on the secondary side of the three-phase transformer is star connection, in the matrix reduction obtained by reducing the dimension of the primary side matrix, iy and iz columns are merged into ix column to obtain the reduced-dimension matrix of the three-phase transformer;

[0084] When the wiring method on the secondary side of the three-phase transformer is delta connection, and when the line voltage phasor on the primary side points to the 12 o'clock position of the clock as the minute hand and the line voltage phasor on the secondary side is at the 11 o'clock position of the clock, in the matrix reduction obtained by reducing the dimension of the primary side matrix, ix column is merged into ic column, iy column is merged into ia column, and iz column is merged into ib column to obtain the reduced-dimension matrix of the three-phase transformer;

[0085] When the wiring method on the secondary side of the three-phase transformer is delta connection, and when the line voltage phasor on the primary side points to the 12 o'clock position of the clock as the minute hand and the line voltage phasor on the secondary side is at the 1 o'clock position of the clock, in the matrix reduction obtained by reducing the dimension of the primary side matrix, ix column is merged into ib column, iy column is merged into ic column, and iz column is merged into ia column to obtain the reduced-dimension matrix of the three-phase transformer.

[0086] According to another aspect of the present invention, there is provided a computer-readable storage medium storing a computer program for executing the method described in any one of the above aspects of the present invention.

[0087] According to another aspect of the present invention, there is provided an electronic device including: a processor; a memory for storing executable instructions of the processor; the processor for reading the executable instructions from the memory and executing the instructions to implement the method described in any one of the above aspects of the present invention.

[0088] First, according to the nameplate information of the three-phase transformer, the resistance value and reactance value of the three-phase transformer are calculated. Then, according to the tap position and rated voltage of the three-phase transformer, the first turns ratio on the primary side of the three-phase transformer and the second turns ratio on the secondary side of the three-phase transformer are calculated. Secondly, based on the resistance value, reactance value, first turns ratio, and second turns ratio of the three-phase transformer, the full matrix of the three-phase transformer is determined. Then, according to the preset matrix dimensionality reduction rule, the full matrix of the three-phase transformer is subjected to dimensionality reduction processing to obtain the dimensionality reduction matrix of the three-phase transformer. Finally, the dimensionality reduction matrix of the three-phase transformer is superimposed into the system matrix for three-phase calculation to perform three-phase power flow calculation and determine the three-phase power flow result of the three-phase transformer. After generating a general full matrix according to the basic parameters of the three-phase transformer, the present invention uses the method of matrix dimensionality reduction to transform the full matrix of the three-phase transformer into the required dimensionality reduction matrix and then superimposes it into the system matrix for three-phase calculation, finally obtaining the three-phase power flow calculation result of the three-phase transformer. Thus, the present invention can retain the physical meaning of transformer variables during the process of order reduction, facilitating the calculation of various variables of the transformer, while reducing the calculation amount. BRIEF DESCRIPTION OF THE DRAWINGS

[0089] The exemplary embodiments of the present invention can be more fully understood by referring to the following drawings:

[0090] Figure 1 is a schematic flowchart of a three-phase calculation method for a transformer based on matrix dimensionality reduction provided by an exemplary embodiment of the present invention;

[0091] Figure 2 is a schematic diagram of an equivalent circuit of a single-phase transformer provided by an exemplary embodiment of the present invention;

[0092] Figure 3 is a schematic structural diagram of a three-phase calculation device for a transformer based on matrix dimensionality reduction provided by an exemplary embodiment of the present invention; and

[0093] Figure 4 is the structure of an electronic device provided by an exemplary embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0094] Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments of the present invention. It should be understood that the present invention is not limited by the exemplary embodiments described herein.

[0095] It should be noted that: unless otherwise specifically stated, the relative arrangements, numerical expressions, and numerical values of the components and steps set forth in these embodiments do not limit the scope of the present invention.

[0096] Those skilled in the art can understand that terms such as "first" and "second" in the embodiments of the present invention are only used to distinguish different steps, devices or modules, etc., and neither represent any specific technical meaning nor indicate an inevitable logical order between them.

[0097] It should also be understood that in the embodiments of the present invention, "a plurality of" may refer to two or more, and "at least one" may refer to one, two or more.

[0098] It should also be understood that for any component, data or structure mentioned in the embodiments of the present invention, in the absence of a clear definition or contrary indication in the context, it can generally be understood as one or more.

[0099] In addition, the term "and / or" in the present invention is merely a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in the present invention generally represents an "or" relationship between the associated objects before and after.

[0100] It should also be understood that the description of each embodiment of the present invention emphasizes the differences between the embodiments, and their similarities can be referred to each other. For the sake of brevity, they will not be elaborated one by one.

[0101] At the same time, it should be understood that for the convenience of description, the dimensions of the various parts shown in the drawings are not drawn in actual proportional relationship.

[0102] The following description of at least one exemplary embodiment is actually only illustrative and in no way a limitation on the present invention and its application or use.

[0103] Technologies, methods and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods and devices should be regarded as part of the specification.

[0104] It should be noted that like reference numerals and letters denote like items in the following figures, and thus, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0105] Embodiments of the present invention can be applied to electronic devices such as terminal devices, computer systems, servers, etc., which can operate together with many other general-purpose or special-purpose computing system environments or configurations. Examples of well-known terminal devices, computing systems, environments, and / or configurations suitable for use with electronic devices such as terminal devices, computer systems, servers, etc. include, but are not limited to: personal computer systems, server computer systems, thin clients, thick clients, handheld or laptop devices, microprocessor-based systems, set-top boxes, programmable consumer electronics, network personal computers, minicomputer systems, mainframe computer systems, and distributed cloud computing technology environments including any of the above systems, and so on.

[0106] Electronic devices such as terminal devices, computer systems, servers, etc. can be described in the general context of computer system-executable instructions (such as program modules) executed by a computer system. Generally, program modules can include routines, programs, target programs, components, logics, data structures, etc., which perform specific tasks or implement specific abstract data types. The computer system / server can be implemented in a distributed cloud computing environment where tasks are executed by remote processing devices linked through a communication network. In a distributed cloud computing environment, program modules can be located on local or remote computing system storage media including storage devices.

[0107] Exemplary method

[0108] Embodiments of the present invention first introduce the three-phase transformer:

[0109] The connection group of the three-phase transformer is represented in alphabetical form. The specific representation method is as follows:

[0110] 1. Capital letters represent the wiring method of the primary side (or the original side), and lowercase letters represent the wiring method of the secondary side (or the secondary side);

[0111] 2. Y (or y) is a star connection, and D (or d) is a delta connection;

[0112] 3. N (or n) represents grounding;

[0113] 4. The numbers are expressed in clock notation to indicate the phase relationship between the primary and secondary line voltages. Specifically, the primary line voltage phasor serves as the minute hand, fixed at the 12 o'clock position on the clock, and the secondary line voltage phasor serves as the hour hand. For example, but not limited to, taking the YNd11 wiring method as an example, the YN in this wiring method indicates that the primary side adopts a star wiring method and the neutral point is grounded, d indicates that the secondary side adopts a delta wiring method, and 11 indicates that when the primary line voltage phasor serves as the minute hand and points at the 12 o'clock position on the clock, the secondary line voltage phasor is at the 11 o'clock position on the clock, that is, the secondary line voltage Uab lags the primary line voltage UAB by 330 degrees.

[0114] At present, my country adopts two wiring methods, Yy and Yd. In my country, voltage levels of 110kV and above are stipulated as high-current grounding systems, so the 110kV side must be grounded. Generally speaking, transformer grounding is derived from the neutral point of the Y-type connection. Therefore, the wiring method of the 110kV side of the main transformer is YN type. Secondly, when the transformer forms a magnetic flux loop, third harmonics will be generated. To ensure that the third harmonic has a path, one side of the transformer must be a triangle connection. Therefore, the step-up transformer of the generator generally adopts the YNd1 method, and the step-up transformer generally adopts the three-winding transformer method of YNyn0d11. The distribution transformer regulates the voltage on the high-voltage side, and Dyn11 can be used in the case of unbalanced load. Yyn0 is generally used for the situation where the three-phase load is basically balanced, the capacity is not large, and the harmonics of the power supply system are not serious. It is often used in 10kV systems, power supply and lighting loads. Yd11 is generally used for medium capacity, 11kV or 35kV distribution systems or plant transformers. YNd11 is generally used for transformers of 110kV and above.

[0115] Figure 1 FIG. 1 is a flow chart of a transformer three-phase calculation method based on matrix dimension reduction provided by an exemplary embodiment of the present invention. This embodiment can be applied to electronic devices, such as Figure 1 As shown, the transformer three-phase calculation method 100 based on matrix dimension reduction includes the following steps:

[0116] Step 101, calculating the resistance value and reactance value of the three-phase transformer according to the nameplate information of the three-phase transformer; calculating the first transformation ratio of the primary side of the three-phase transformer and the second transformation ratio of the secondary side of the three-phase transformer according to the tap position and rated voltage of the three-phase transformer.

[0117] In the embodiment of the present invention, the three-phase transformer is first pre-processed as a single-phase transformer. The single-phase transformer has 4 ports. The equivalent circuit of the single-phase transformer is as follows: Figure 2 As shown. Where, is the impedance parameter of the transformer. Considering that the taps at both ends of the transformer can be adjusted, two transformation ratios and are set. Where, is the transformation ratio of the primary side of the transformer, and is the transformation ratio of the secondary side of the transformer.

[0118] It should be specifically noted here that there is no specific order precedence between the calculation of the resistance value and the reactance value and the calculation of the first turns ratio and the second turns ratio. In the embodiments of the present invention, the resistance value and the reactance value can be calculated first, and then the first turns ratio and the second turns ratio can be calculated. Or the first turns ratio and the second turns ratio can be calculated first, and then the resistance value and the reactance value can be calculated. It is also possible to calculate the resistance value, the reactance value, the first turns ratio, and the second turns ratio in parallel.

[0119] Optionally, according to the nameplate information of the three-phase transformer and using the following formula, the resistance value of the three-phase transformer is calculated and the reactance value :

[0120]

[0121] In the formula, is the resistance value of the three-phase transformer, is the reactance value of the three-phase transformer, is the rated capacity of the three-phase transformer, is the rated voltage of the three-phase transformer, is the short-circuit loss, is the percentage of impedance voltage.

[0122] Optionally, according to the tap position and the rated voltage of the three-phase transformer, using the following formula, the first turns ratio of the primary side of the three-phase transformer and the second turns ratio of the secondary side of the three-phase transformer are calculated:

[0123]

[0124] In the formula, is the tap position of the primary side of the three-phase transformer, is the tap position of the secondary side of the three-phase transformer, is the rated voltage of the primary side of the three-phase transformer, is the rated voltage of the secondary side of the three-phase transformer.

[0125] Step 102: Determine the full matrix of the three-phase transformer based on the resistance value, the reactance value, the first turns ratio, and the second turns ratio of the three-phase transformer.

[0126] Optionally, determining the full matrix of the three-phase transformer based on the resistance value, the reactance value, the first turns ratio, and the second turns ratio of the three-phase transformer includes: treating the three-phase transformer as three single-phase transformers, determining the single-phase matrix of each single-phase transformer based on the resistance value, the reactance value, the first turns ratio, and the second turns ratio of the three-phase transformer; and determining the full matrix of the three-phase transformer based on the single-phase matrices of the three single-phase transformers.

[0127] Optionally, based on the resistance value, reactance value, first turns ratio, and second turns ratio of the three-phase transformer, determine the single-phase matrix of each single-phase transformer as:

[0128]

[0129] And, based on the single-phase matrices of the three single-phase transformers, determine the full matrix of the three-phase transformer as:

[0130]

[0131] Wherein, the elements in the matrix , element , element , element , element , element , is the resistance value of the three-phase transformer, is the reactance value of the three-phase transformer, is the first turns ratio on the primary side of the three-phase transformer, is the second turns ratio on the secondary side of the three-phase transformer; i represents the primary side of the three-phase transformer, j represents the secondary side of the three-phase transformer; ia / ja / ix / jx are the 4 ports of phase A of the three-phase transformer respectively, ib / jb / iy / jy are the 4 ports of phase B of the three-phase transformer, ic / jc / iz / jz are the 4 ports of phase C of the three-phase transformer.

[0132] Step 103, according to the preset matrix dimensionality reduction rule, perform dimensionality reduction processing on the full matrix of the three-phase transformer to obtain the dimensionality reduction matrix of the three-phase transformer.

[0133] In the embodiments of the present invention, to maintain universality, the two ends of the three-phase transformer in the present invention are processed separately, and the matrix dimensionality reduction method is also processed separately according to the port wiring method at both ends of the three-phase transformer. The port wiring methods at both ends of the three-phase transformer are generally divided into the following four situations, and for different situations, the full matrix of the three-phase transformer is processed according to different matrix dimensionality reduction rules:

[0134] 1) Situation 1: YN wiring method. The matrix dimensionality reduction rule corresponding to this wiring method is: all the xyz columns of this port are eliminated;

[0135] 2) Situation 2: Y wiring method. The matrix dimensionality reduction rule corresponding to this wiring method is: the yz columns of this port are merged into the x column;

[0136] 3) Case 3: D11 wiring method. The corresponding matrix dimension reduction rule for this wiring method is: the x column of this port is merged into the c column, the y column is merged into the a column, and the z column is merged into the b column;

[0137] 4) Case 4: D1 wiring method. The corresponding matrix dimension reduction rule for this wiring method is: the x column of this port is merged into the b column, the y column is merged into the c column, and the z column is merged into the a column.

[0138] Optionally, according to the preset matrix dimension reduction rule, perform dimension reduction processing on the full matrix of the three-phase transformer to obtain the dimension-reduced matrix of the three-phase transformer, including: perform primary-side matrix dimension reduction on the full matrix of the three-phase transformer according to the wiring method of the primary side of the three-phase transformer; perform secondary-side matrix dimension reduction on the matrix obtained after the primary-side matrix dimension reduction according to the wiring method of the secondary side of the three-phase transformer to obtain the dimension-reduced matrix of the three-phase transformer.

[0139] Optionally, perform primary-side matrix dimension reduction on the full matrix of the three-phase transformer according to the wiring method of the primary side of the three-phase transformer, including: determine the wiring method of the primary side of the three-phase transformer; when the wiring method of the primary side of the three-phase transformer is star wiring and the neutral point is grounded, eliminate all the ix , iy and iz columns in the full matrix of the three-phase transformer; when the wiring method of the primary side of the three-phase transformer is star wiring, merge the iy and iz columns in the full matrix of the three-phase transformer into the ix column; when the wiring method of the primary side of the three-phase transformer is delta wiring, and when the primary-side line voltage phasor points to the 12 o'clock position of the clock as the minute hand and the secondary-side line voltage phasor is at the 11 o'clock position of the clock, merge the ix column in the full matrix of the three-phase transformer into the ic column, the iy column into the ia column, and the iz column into the ib column; when the wiring method of the primary side of the three-phase transformer is delta wiring, and when the primary-side line voltage phasor points to the 12 o'clock position of the clock as the minute hand and the secondary-side line voltage phasor is at the 1 o'clock position of the clock, merge the ix column in the full matrix of the three-phase transformer into the ib column, the iy column into the ic column, and the iz column into the ia column.

[0140] Optionally, according to the wiring mode of the secondary side of the three-phase transformer, perform secondary-side matrix dimensionality reduction on the matrix obtained after dimensionality reduction of the primary-side matrix to obtain the dimensionality-reduced matrix of the three-phase transformer, including:

[0141] Determine the wiring mode of the secondary side of the three-phase transformer; when the wiring mode of the secondary side of the three-phase transformer is star wiring and the neutral point is grounded, in the matrix obtained after dimensionality reduction of the primary-side matrix ix , iy and iz columns are all eliminated to obtain the dimensionality-reduced matrix of the three-phase transformer; when the wiring mode of the secondary side of the three-phase transformer is star wiring, in the matrix obtained after dimensionality reduction of the primary-side matrix iy and iz columns are merged into ix column to obtain the dimensionality-reduced matrix of the three-phase transformer; when the wiring mode of the secondary side of the three-phase transformer is delta wiring, and when the primary-side line voltage phasor points to the 12 o'clock position of the clock as the minute hand and the secondary-side line voltage phasor is at the 11 o'clock position of the clock, in the matrix obtained after dimensionality reduction of the primary-side matrix ix column is merged into ic column, iy column is merged into ia column, and iz column is merged into ib column to obtain the dimensionality-reduced matrix of the three-phase transformer; when the wiring mode of the secondary side of the three-phase transformer is delta wiring, and when the primary-side line voltage phasor points to the 12 o'clock position of the clock as the minute hand and the secondary-side line voltage phasor is at the 1 o'clock position of the clock, in the matrix obtained after dimensionality reduction of the primary-side matrix ix column is merged into ib column, iy column is merged into ic column, and iz column is merged into ia column to obtain the dimensionality-reduced matrix of the three-phase transformer.

[0142] In the embodiments of the present invention, taking the wiring mode of the three-phase transformer as "YNd11" as an example, it is described in detail how to perform dimensionality reduction processing on the full matrix of the three-phase transformer according to the above preset matrix dimensionality reduction rules to obtain the dimensionality-reduced matrix of the three-phase transformer:

[0143] First step, according to the wiring mode of the primary side of the three-phase transformer (i.e., YN wiring), process the ports of the primary side (i side). Then, in the full matrix of the three-phase transformer, all elements of ix / iy / iz columns are all eliminated, and the full matrix becomes:

[0144]

[0145] In the second step, according to the wiring method of the secondary side of the three-phase transformer (i.e., d11 wiring), the matrix obtained after dimension reduction of the primary side matrix is further dimension-reduced. Therefore, the jx column in the matrix obtained after dimension reduction of the primary side matrix needs to be merged into the jc column, jy the column is merged into the ja column, jz the column is merged into the jb column, and the obtained dimension-reduced matrix is:

[0146]

[0147] Optionally, the obtained dimension-reduced matrix of the three-phase transformer is:

[0148]

[0149] where i represents the primary side of the three-phase transformer and j represents the secondary side of the three-phase transformer; ia / ja are the two ports of phase A of the three-phase transformer, ib / jb are the two ports of phase B of the three-phase transformer, ic / jc are the two ports of phase C of the three-phase transformer; each element in the dimension-reduced matrix ( ) is obtained by eliminating or merging the column elements in the full matrix of the three-phase transformer according to the preset matrix dimension reduction rule.

[0150] In the embodiment of the present invention, for a two-winding transformer, according to the preset matrix dimension reduction rule, after dimension reduction of the full matrix of the two-winding transformer, a 12×12 matrix can be reduced to a 6×6 matrix. In addition, for a three-winding transformer, according to the preset matrix dimension reduction rule, after dimension reduction of the full matrix of the three-winding transformer, a 16×16 matrix can be reduced to a 9×9 matrix.

[0151] Step 104, superimpose the dimension-reduced matrix of the three-phase transformer onto the system matrix for three-phase calculation to perform three-phase power flow calculation and determine the three-phase power flow results of the three-phase transformer.

[0152] Optionally, superimposing the dimension-reduced matrix of the three-phase transformer onto the system matrix for three-phase calculation to perform three-phase power flow calculation and determine the three-phase power flow results of the three-phase transformer includes:

[0153] Superimpose the dimension-reduced matrix of the three-phase transformer onto the system matrix for three-phase calculation to obtain the voltages of each node in the system, where each port of the three-phase transformer is regarded as a node of the system;

[0154] Based on the dimensionality reduction matrix of the three-phase transformer and the voltages of each port of the three-phase transformer, the current of the three-phase transformer is calculated using the following formula:

[0155]

[0156] Wherein, represents the dimensionality reduction matrix of the three-phase transformer, represents the voltages of each port of the three-phase transformer;

[0157] Based on the voltages and currents of each port of the three-phase transformer, the power of the three-phase transformer is calculated using the following formula:

[0158]

[0159] Wherein, represents the voltages of each port of the three-phase transformer, represents conjugate;

[0160] represents the currents of each port of the three-phase transformer.

[0161] Therefore, the present invention first calculates the resistance value and reactance value of the three-phase transformer according to the nameplate information of the three-phase transformer. Then, according to the tap position and rated voltage of the three-phase transformer, the first turns ratio of the primary side of the three-phase transformer and the second turns ratio of the secondary side of the three-phase transformer are calculated. Secondly, based on the resistance value, reactance value, first turns ratio and second turns ratio of the three-phase transformer, the full matrix of the three-phase transformer is determined. Then, according to the preset matrix dimensionality reduction rule, the full matrix of the three-phase transformer is dimensionally reduced to obtain the dimensionality reduction matrix of the three-phase transformer. Finally, the dimensionality reduction matrix of the three-phase transformer is superimposed into the system matrix for three-phase calculation to perform three-phase power flow calculation, and the three-phase power flow result of the three-phase transformer is determined. After generating a general full matrix according to the basic parameters of the three-phase transformer, the present invention uses the method of matrix dimensionality reduction to transform the full matrix of the three-phase transformer into the required dimensionality reduction matrix and then superimposes it into the system matrix for three-phase calculation, and finally obtains the three-phase power flow calculation result of the three-phase transformer. Therefore, the present invention can retain the physical meaning of the transformer variables during the process of order reduction, which is beneficial to calculating various variables of the transformer, and at the same time reduces the amount of calculation.

[0162] Exemplary system

[0163] Figure 3 is a schematic structural diagram of a transformer three-phase calculation device based on matrix dimensionality reduction provided by an exemplary embodiment of the present invention. As Figure 3 shown, the device 300 includes:

[0164] A calculation module 310, configured to calculate the resistance value and reactance value of a three-phase transformer according to the nameplate information of the three-phase transformer; and calculate a first turns ratio of the primary side of the three-phase transformer and a second turns ratio of the secondary side of the three-phase transformer according to the tap position and rated voltage of the three-phase transformer.

[0165] A full matrix determination module 320, configured to determine the full matrix of the three-phase transformer based on the resistance value, reactance value, first turns ratio, and second turns ratio of the three-phase transformer.

[0166] A dimensionality reduction matrix determination module 330, configured to perform dimensionality reduction processing on the full matrix of the three-phase transformer according to a preset matrix dimensionality reduction rule to obtain a dimensionality reduction matrix of the three-phase transformer.

[0167] A three-phase power flow result determination module 340, configured to superimpose the dimensionality reduction matrix of the three-phase transformer into a system matrix for three-phase calculation to perform three-phase power flow calculation and determine the three-phase power flow result of the three-phase transformer.

[0168] Optionally, the calculation module 310 is specifically configured to:

[0169] According to the nameplate information of the three-phase transformer and using the following formula, calculate the resistance value of the three-phase transformer and the reactance value :

[0170]

[0171] In the formula, is the resistance value of the three-phase transformer, is the reactance value of the three-phase transformer, is the rated capacity of the three-phase transformer, is the rated voltage of the three-phase transformer, is the short-circuit loss, is the percentage of impedance voltage.

[0172] Optionally, the calculation module 310 is specifically configured to:

[0173] According to the tap position and rated voltage of the three-phase transformer and using the following formula, calculate the first turns ratio of the primary side of the three-phase transformer and the second turns ratio of the secondary side of the three-phase transformer :

[0174]

[0175] In the formula, is the tap position of the primary side of the three-phase transformer, is the tap position of the secondary side of the three-phase transformer, is the rated voltage of the primary side of the three-phase transformer, is the rated voltage of the secondary side of the three-phase transformer.

[0176] Optionally, the full matrix determination module 320 is specifically configured to:

[0177] Treat the three-phase transformer as three single-phase transformers, and determine the single-phase matrix of each single-phase transformer based on the resistance value, reactance value, first turns ratio, and second turns ratio of the three-phase transformer;

[0178] Determine the full matrix of the three-phase transformer based on the single-phase matrices of the three single-phase transformers.

[0179] Optionally, the single-phase matrix of each single-phase transformer determined by the full matrix determination module 320 is:

[0180]

[0181] And, the full matrix of the three-phase transformer determined by the full matrix determination module 320 is:

[0182]

[0183] Among them, the elements in the matrix , element , element , element , element , element , is the resistance value of the three-phase transformer, is the reactance value of the three-phase transformer, is the first turns ratio of the primary side of the three-phase transformer, is the second turns ratio of the secondary side of the three-phase transformer; i represents the primary side of the three-phase transformer, j represents the secondary side of the three-phase transformer; ia / ja / ix / jx are the 4 ports of phase A of the three-phase transformer respectively, ib / jb / iy / jy are the 4 ports of phase B of the three-phase transformer, ic / jc / iz / jz are the 4 ports of phase C of the three-phase transformer.

[0184] Optionally, the dimensionality reduction matrix determination module 330 is specifically configured to:

[0185] Perform matrix dimensionality reduction on the primary side of the full matrix of the three-phase transformer according to the wiring method of the primary side of the three-phase transformer;

[0186] Perform matrix dimensionality reduction on the secondary side of the matrix obtained after dimensionality reduction on the primary side according to the wiring method of the secondary side of the three-phase transformer, and obtain the dimensionality reduction matrix of the three-phase transformer.

[0187] Optionally, the dimensionality reduction matrix determination module 330 is also specifically configured to:

[0188] Determine the wiring method of the primary side of the three-phase transformer;

[0189] When the wiring method of the primary side of the three-phase transformer is star connection and the neutral point is grounded, in the full matrix of the three-phase transformer, ix , iy and iz All columns are eliminated;

[0190] When the wiring method of the primary side of the three-phase transformer is star connection, in the full matrix of the three-phase transformer, iy and iz Columns are merged into ix Column;

[0191] When the wiring method of the primary side of the three-phase transformer is delta connection, and when the line voltage phasor of the primary side points to the 12 o'clock position of the clock as the minute hand and the line voltage phasor of the secondary side is at the 11 o'clock position of the clock, in the full matrix of the three-phase transformer, ix Columns are merged into ic Column, iy Columns are merged into ia Column and iz Columns are merged into ib Column;

[0192] When the wiring method of the primary side of the three-phase transformer is delta connection, and when the line voltage phasor of the primary side points to the 12 o'clock position of the clock as the minute hand and the line voltage phasor of the secondary side is at the 1 o'clock position of the clock, in the full matrix of the three-phase transformer, ix Columns are merged into ib Column, iy Columns are merged into ic Column and iz Columns are merged into ia Column.

[0193] Optionally, the dimensionality reduction matrix determination module 330 is further specifically configured to:

[0194] Determine the wiring method of the secondary side of the three-phase transformer;

[0195] When the wiring method of the secondary side of the three-phase transformer is star connection and the neutral point is grounded, in the matrix dimensionality reduction obtained after dimensionality reduction of the primary side matrix, ix , iy and iz All columns are eliminated to obtain the dimensionality reduction matrix of the three-phase transformer;

[0196] When the wiring method of the secondary side of the three-phase transformer is star connection, in the matrix dimensionality reduction obtained after dimensionality reduction of the primary side matrix, iy and izThe columns are merged into ix columns to obtain the dimensionality reduction matrix of the three-phase transformer;

[0197] When the wiring method on the secondary side of the three-phase transformer is the delta connection method, and when the line voltage phasor on the primary side points to the 12 o'clock position of the clock as the minute hand, and the line voltage phasor on the secondary side is at the 11 o'clock position of the clock, in the dimensionality reduction of the matrix obtained by reducing the dimensionality of the primary side matrix, ix the columns are merged into ic columns, iy the columns are merged into ia columns, and iz the columns are merged into ib columns to obtain the dimensionality reduction matrix of the three-phase transformer;

[0198] When the wiring method on the secondary side of the three-phase transformer is the delta connection method, and when the line voltage phasor on the primary side points to the 12 o'clock position of the clock as the minute hand, and the line voltage phasor on the secondary side is at the 1 o'clock position of the clock, in the dimensionality reduction of the matrix obtained by reducing the dimensionality of the primary side matrix, ix the columns are merged into ib columns, iy the columns are merged into ic columns, and iz the columns are merged into ia columns to obtain the dimensionality reduction matrix of the three-phase transformer.

[0199] Optionally, the dimensionality reduction matrix of the three-phase transformer obtained by the dimensionality reduction matrix determination module 330 is:

[0200]

[0201] where, i represents the primary side of the three-phase transformer, and j represents the secondary side of the three-phase transformer; ia / ja are the two ports of phase A of the three-phase transformer, ib / jb are the two ports of phase B of the three-phase transformer, ic / jc are the two ports of phase C of the three-phase transformer; each element in the dimensionality reduction matrix is an element obtained by eliminating or merging the column elements in the full matrix of the three-phase transformer according to the preset matrix dimensionality reduction rule.

[0202] Optionally, the three-phase power flow result determination module 340 is specifically configured to:

[0203] Superimpose the dimensionality reduction matrix of the three-phase transformer onto the system matrix for three-phase power flow calculation to obtain the voltages of each node in the system, where each port of the three-phase transformer is regarded as a node of the system;

[0204] Based on the dimensionality reduction matrix of the three-phase transformer and the voltages of each port of the three-phase transformer, the current of the three-phase transformer is calculated using the following formula:

[0205]

[0206] Wherein, represents the dimensionality reduction matrix of the three-phase transformer, represents the voltages of each port of the three-phase transformer;

[0207] Based on the voltages and currents of each port of the three-phase transformer, the power of the three-phase transformer is calculated using the following formula:

[0208]

[0209] Wherein, represents the voltages of each port of the three-phase transformer, represents conjugate;

[0210] represents the currents of each port of the three-phase transformer.

[0211] The three-phase calculation device 300 of the transformer based on matrix dimensionality reduction in the embodiment of the present invention corresponds to the three-phase calculation method 100 of the transformer based on matrix dimensionality reduction in another embodiment of the present invention, which will not be elaborated here.

[0212] Exemplary electronic device

[0213] Figure 4 is the structure of an electronic device provided by an exemplary embodiment of the present invention. The electronic device can be any one or both of the first device and the second device, or a stand-alone device independent of them, and the stand-alone device can communicate with the first device and the second device to receive the input signals collected from them. Figure 4 Illustrates a block diagram of an electronic device according to an embodiment of the present invention. As Figure 4 shown, the electronic device 40 includes one or more processors 41 and a memory 42.

[0214] The processor 41 can be a central processing unit (CPU) or other forms of processing units with data processing capabilities and / or instruction execution capabilities, and can control other components in the electronic device to perform desired functions.

[0215] The memory 42 may include one or more computer program products, and the computer program products may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may include, for example, random access memory (RAM) and / or cache memory, etc. The non-volatile memory may include, for example, read-only memory (ROM), hard disk, flash memory, etc. One or more computer program instructions may be stored on the computer-readable storage media, and the processor 41 may run the program instructions to implement the method for information mining of historical change records in the software programs of the various embodiments of the present invention described above and / or other desired functions. In one example, the electronic device may further include: an input system 43 and an output system 44, and these components are interconnected through a bus system and / or other forms of connection mechanisms (not shown).

[0216] In addition, the input system 43 may further include, for example, a keyboard, a mouse, and so on.

[0217] The output system 44 may output various information to the outside. The output device 44 may include, for example, a display, a speaker, a printer, and a communication network and its connected remote output devices, and so on.

[0218] Of course, for simplicity, Figure 4 only some of the components related to the present invention in the electronic device are shown, and components such as buses, input / output interfaces, etc. are omitted. In addition, according to specific application scenarios, the electronic device may further include any other appropriate components.

[0219] Exemplary computer program product and computer-readable storage medium

[0220] In addition to the above methods and devices, embodiments of the present invention may also be computer program products, which include computer program instructions that, when run by a processor, cause the processor to execute the steps in the method for information mining of historical change records according to various embodiments of the present invention described in the "Exemplary Method" section above of this specification.

[0221] The computer program products may be written in any combination of one or more programming languages for programming code to perform the operations of the embodiments of the present invention. The programming languages include object-oriented programming languages, such as ja va, C++, etc., and also include conventional procedural programming languages, such as the "C" language or similar programming languages. The program code may be executed entirely on the user computing device, partially on the user device, executed as an independent software package, partially on the user computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0222] In addition, an embodiment of the present invention may also be a computer-readable storage medium storing computer program instructions, which, when run by a processor, cause the processor to execute the steps in the method of information mining on historical change records according to various embodiments of the present invention described in the above "Exemplary Method" section of this specification.

[0223] The computer-readable storage medium may employ any combination of one or more readable media. The readable media may be a readable signal medium or a readable storage medium. The readable storage medium may, for example, include but is not limited to an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination of the above. More specific examples (a non-exhaustive list) of the readable storage medium include: an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above.

[0224] The basic principles of the present invention have been described above in conjunction with specific embodiments. However, it should be noted that the advantages, benefits, effects, etc. mentioned in the present invention are only examples and not limitations, and it cannot be considered that these advantages, benefits, effects, etc. are essential for each embodiment of the present invention. In addition, the above-disclosed specific details are only for the purposes of illustration and facilitating understanding, rather than limitations. The above details do not limit the present invention to necessarily implement using the above specific details.

[0225] Each embodiment in this specification is described in a progressive manner. The key point of each embodiment is to illustrate the differences from other embodiments. For the same or similar parts among the embodiments, reference can be made to each other. For the system embodiment, since it basically corresponds to the method embodiment, the description is relatively simple, and reference can be made to the relevant part of the method embodiment for the relevant content.

[0226] The block diagrams of the devices, systems, equipment, and systems involved in the present invention are only illustrative examples and do not intend to require or imply that they must be connected, arranged, and configured in the manner shown in the block diagrams. As those skilled in the art will recognize, these devices, systems, equipment, and systems can be connected, arranged, and configured in any manner. Words such as "including", "comprising", "having", etc. are open-ended terms, meaning "including but not limited to", and can be used interchangeably with each other. The words "or" and "and" used herein refer to the word "and / or" and can be used interchangeably with each other, unless the context clearly indicates otherwise. The word "such as" used herein refers to the phrase "such as but not limited to" and can be used interchangeably with each other.

[0227] The methods and systems of the present invention can be implemented in many ways. For example, the methods and systems of the present invention can be implemented by software, hardware, firmware, or any combination of software, hardware, and firmware. The above order of steps for the methods is for illustrative purposes only, and the steps of the methods of the present invention are not limited to the specific order described above, unless otherwise specifically stated. In addition, in some embodiments, the present invention can also be implemented as a program recorded in a recording medium, and these programs include machine-readable instructions for implementing the methods according to the present invention. Thus, the present invention also covers a recording medium storing a program for executing the methods according to the present invention.

[0228] It should also be noted that in the systems, devices, and methods of the present invention, each component or each step can be decomposed and / or recombined. These decompositions and / or recombinations should be regarded as equivalent solutions of the present invention. The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these aspects are very obvious to those skilled in the art, and the general principles defined herein can be applied to other aspects without departing from the scope of the present invention. Therefore, the present invention is not intended to be limited to the aspects shown herein, but rather to the broadest scope consistent with the principles and novel features disclosed herein.

[0229] The above description has been given for purposes of illustration and description. In addition, this description is not intended to limit the embodiments of the present invention to the forms disclosed herein. Although multiple example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and subcombinations thereof.

Claims

1. A three-phase calculation method for transformers based on matrix dimensionality reduction, characterized in that, it includes: Calculating the resistance value and reactance value of the three-phase transformer according to the nameplate information of the three-phase transformer; calculating the first transformation ratio on the primary side of the three-phase transformer and the second transformation ratio on the secondary side of the three-phase transformer according to the tap position and rated voltage of the three-phase transformer; Determining the full matrix of the three-phase transformer based on the resistance value, reactance value, first transformation ratio and second transformation ratio of the three-phase transformer; Performing dimensionality reduction processing on the full matrix of the three-phase transformer according to the preset matrix dimensionality reduction rule to obtain the dimensionality reduction matrix of the three-phase transformer; Superimposing the dimensionality reduction matrix of the three-phase transformer into the system matrix for three-phase calculation to perform three-phase power flow calculation and determine the three-phase power flow result of the three-phase transformer; Among them, determining the full matrix of the three-phase transformer based on the resistance value, reactance value, first transformation ratio and second transformation ratio of the three-phase transformer includes: Treating the three-phase transformer as three single-phase transformers, and determining the single-phase matrix of each single-phase transformer based on the resistance value, reactance value, first transformation ratio and second transformation ratio of the three-phase transformer; Determining the full matrix of the three-phase transformer based on the single-phase matrices of the three single-phase transformers; Among them, determining the single-phase matrix of each single-phase transformer based on the resistance value, reactance value, first transformation ratio and second transformation ratio of the three-phase transformer is: And, determining the full matrix of the three-phase transformer based on the single-phase matrices of the three single-phase transformers is: Among them, the elements in the matrix element element element element element R T is the resistance value of the three-phase transformer, X T is the reactance value of the three-phase transformer, T r1 is the first turns ratio of the primary side of the three-phase transformer, T r2 is the second turns ratio of the secondary side of the three-phase transformer, j is the imaginary number; i represents the primary side of the three-phase transformer, j represents the secondary side of the three-phase transformer; ia / ja / ix / jx are the 4 ports of phase A of the three-phase transformer respectively, ib / jb / iy / jy are the 4 ports of phase B of the three-phase transformer, ic / jc / iz / jz are the 4 ports of phase C of the three-phase transformer; Among them, performing dimensionality reduction processing on the full matrix of the three-phase transformer according to the preset matrix dimensionality reduction rule to obtain the dimensionality reduction matrix of the three-phase transformer includes: Performing primary-side matrix dimensionality reduction on the full matrix of the three-phase transformer according to the wiring method on the primary side of the three-phase transformer; Performing secondary-side matrix dimensionality reduction on the matrix obtained after the primary-side matrix dimensionality reduction according to the wiring method on the secondary side of the three-phase transformer to obtain the dimensionality reduction matrix of the three-phase transformer.

2. The method according to claim 1, characterized in that, Calculating the resistance value and reactance value of the three-phase transformer according to the nameplate information of the three-phase transformer includes: According to the nameplate information of the three-phase transformer and using the following formula, the resistance value R of the three-phase transformer is calculated T and the reactance value X T : Wherein, R T is the resistance value of the three-phase transformer, X T is the reactance value of the three-phase transformer, S N is the rated capacity of the three-phase transformer, U N is the rated voltage of the three-phase transformer, ΔP is the short-circuit loss, U S % is the percentage of impedance voltage.

3. The method according to claim 1, characterized in that, Calculating the first transformation ratio on the primary side of the three-phase transformer and the second transformation ratio on the secondary side of the three-phase transformer according to the tap position and rated voltage of the three-phase transformer includes: According to the tap position and rated voltage of the three-phase transformer, the first turns ratio \(T_1\) of the primary side of the three-phase transformer is calculated using the following formula r1 and the second turns ratio \(T_2\) of the secondary side of the three-phase transformer r2 : Wherein, V1 is the tap position on the primary side of the three-phase transformer, V2 is the tap position on the secondary side of the three-phase transformer, V1 base is the rated voltage on the primary side of the three-phase transformer, V2 base is the rated voltage on the secondary side of the three-phase transformer.

4. The method according to claim 1, characterized in that, Performing primary-side matrix dimensionality reduction on the full matrix of the three-phase transformer according to the wiring method on the primary side of the three-phase transformer includes: Determining the wiring method on the primary side of the three-phase transformer; When the wiring method on the primary side of the three-phase transformer is star connection with the neutral point grounded, all the ix, iy and iz columns in the full matrix of the three-phase transformer are eliminated; When the wiring method on the primary side of the three-phase transformer is star connection, the iy and iz columns in the full matrix of the three-phase transformer are merged into the ix column; The wiring method on the primary side of the three-phase transformer is the delta connection method. And when the line voltage phasor on the primary side points to the 12 o'clock position of the clock as the minute hand, and the line voltage phasor on the secondary side is at the 11 o'clock position of the clock, the ix column in the full matrix of the three-phase transformer is merged into the ic column, the iy column is merged into the ia column, and the iz column is merged into the ib column; The wiring method on the primary side of the three-phase transformer is the delta connection method. And when the line voltage phasor on the primary side points to the 12 o'clock position of the clock as the minute hand, and the line voltage phasor on the secondary side is at the 1 o'clock position of the clock, the ix column in the full matrix of the three-phase transformer is merged into the ib column, the iy column is merged into the ic column, and the iz column is merged into the ia column.

5. The method according to claim 4, characterized in that, According to the wiring method on the secondary side of the three-phase transformer, perform secondary-side matrix reduction on the matrix reduction obtained after reducing the dimension of the primary-side matrix to obtain the reduced-dimension matrix of the three-phase transformer, including: Determine the wiring method on the secondary side of the three-phase transformer; When the wiring method on the secondary side of the three-phase transformer is the star connection method and the neutral point is grounded, all the ix, iy, and iz columns in the matrix reduction obtained after reducing the dimension of the primary-side matrix are eliminated to obtain the reduced-dimension matrix of the three-phase transformer; When the wiring method on the secondary side of the three-phase transformer is the star connection method, the iy and iz columns in the matrix reduction obtained after reducing the dimension of the primary-side matrix are merged into the ix column to obtain the reduced-dimension matrix of the three-phase transformer; When the wiring method on the secondary side of the three-phase transformer is the delta connection method, and when the line voltage phasor on the primary side points to the 12 o'clock position of the clock as the minute hand, and the line voltage phasor on the secondary side is at the 11 o'clock position of the clock, the ix column in the matrix reduction obtained after reducing the dimension of the primary-side matrix is merged into the ic column, the iy column is merged into the ia column, and the iz column is merged into the ib column to obtain the reduced-dimension matrix of the three-phase transformer; When the wiring method on the secondary side of the three-phase transformer is the delta connection method, and when the line voltage phasor on the primary side points to the 12 o'clock position of the clock as the minute hand, and the line voltage phasor on the secondary side is at the 1 o'clock position of the clock, the ix column in the matrix reduction obtained after reducing the dimension of the primary-side matrix is merged into the ib column, the iy column is merged into the ic column, and the iz column is merged into the ia column to obtain the reduced-dimension matrix of the three-phase transformer.

6. The method according to claim 5, characterized in that, The obtained reduced-dimension matrix of the three-phase transformer is: Among them, i represents the primary side of the three-phase transformer, and j represents the secondary side of the three-phase transformer; ia / ja are the two ports of phase A of the three-phase transformer, ib / jb are the two ports of phase B of the three-phase transformer, and ic / jc are the two ports of phase C of the three-phase transformer; each element (y aa1 ~y ccm ) in the dimensionality reduction matrix is an element obtained by eliminating or combining the elements of each column in the full matrix of the three-phase transformer according to the preset matrix dimensionality reduction rule.

7. The method according to claim 6, characterized in that, Superimpose the reduced-dimension matrix of the three-phase transformer onto the system matrix for three-phase calculation to perform three-phase power flow calculation and determine the three-phase power flow results of the three-phase transformer, including: Superimpose the reduced-dimension matrix of the three-phase transformer onto the system matrix for three-phase calculation to obtain the voltages of each node in the system, where each port of the three-phase transformer is regarded as a node of the system; Based on the reduced-dimension matrix of the three-phase transformer and the voltages of each port of the three-phase transformer, use the following formula to calculate the current of the three-phase transformer: Among them, represents the dimensionality reduction matrix of the three-phase transformer, represents the voltages of each port of the three-phase transformer; Based on the voltages and currents of each port of the three-phase transformer, use the following formula to calculate the power of the three-phase transformer: Among them, represents the voltages of the respective ports of the three-phase transformer, and conj represents conjugate; represents the currents of the respective ports of the three-phase transformer.

8. A three-phase calculation device for a transformer based on matrix dimensionality reduction, characterized in that, it includes: a calculation module for calculating the resistance value and reactance value of a three-phase transformer according to the nameplate information of the three-phase transformer; calculating the first transformation ratio of the primary side of the three-phase transformer and the second transformation ratio of the secondary side of the three-phase transformer according to the tap position and rated voltage of the three-phase transformer; a full matrix determination module for determining the full matrix of the three-phase transformer based on the resistance value, reactance value, first transformation ratio and second transformation ratio of the three-phase transformer; a dimensionality reduction matrix determination module for performing dimensionality reduction processing on the full matrix of the three-phase transformer according to a preset matrix dimensionality reduction rule to obtain the dimensionality reduction matrix of the three-phase transformer; a three-phase power flow result determination module for superimposing the dimensionality reduction matrix of the three-phase transformer into the system matrix for three-phase calculation to perform three-phase power flow calculation and determine the three-phase power flow result of the three-phase transformer; wherein, determining the full matrix of the three-phase transformer based on the resistance value, reactance value, first transformation ratio and second transformation ratio of the three-phase transformer includes: treating the three-phase transformer as three single-phase transformers, and determining the single-phase matrix of each single-phase transformer based on the resistance value, reactance value, first transformation ratio and second transformation ratio of the three-phase transformer; determining the full matrix of the three-phase transformer based on the single-phase matrices of the three single-phase transformers; wherein, determining the single-phase matrix of each single-phase transformer based on the resistance value, reactance value, first transformation ratio and second transformation ratio of the three-phase transformer is: and, determining the full matrix of the three-phase transformer based on the single-phase matrices of the three single-phase transformers is: Among them, the elements in the matrix element element element element element R T is the resistance value of the three-phase transformer, X T is the reactance value of the three-phase transformer, T r1 is the first turns ratio of the primary side of the three-phase transformer, T r2 is the second turns ratio of the secondary side of the three-phase transformer, j is the imaginary number; i represents the primary side of the three-phase transformer, j represents the secondary side of the three-phase transformer; ia / ja / ix / jx are the 4 ports of phase A of the three-phase transformer respectively, ib / jb / iy / jy are the 4 ports of phase B of the three-phase transformer, ic / jc / iz / jz are the 4 ports of phase C of the three-phase transformer; wherein, the dimensionality reduction matrix determination module is specifically used for: performing matrix dimensionality reduction on the primary side of the full matrix of the three-phase transformer according to the wiring mode of the primary side of the three-phase transformer; performing matrix dimensionality reduction on the secondary side of the matrix obtained after dimensionality reduction on the primary side according to the wiring mode of the secondary side of the three-phase transformer to obtain the dimensionality reduction matrix of the three-phase transformer.

9. The device according to claim 8, characterized in that, the calculation module is specifically used for: According to the nameplate information of the three-phase transformer and using the following formula, the resistance value R of the three-phase transformer is calculated T and the reactance value X T : where, R T is the resistance value of the three-phase transformer, X T is the reactance value of the three-phase transformer, S N is the rated capacity of the three-phase transformer, U N is the rated voltage of the three-phase transformer, ΔP is the short-circuit loss, U S % is the percentage of impedance voltage.

10. The device according to claim 8, characterized in that, the calculation module is specifically used for: According to the tap position and rated voltage of the three-phase transformer, the first turns ratio T of the primary side of the three-phase transformer is calculated using the following formula r1 and the second turns ratio T of the secondary side of the three-phase transformer r2 : Wherein, V1 is the tap position on the primary side of the three-phase transformer, V2 is the tap position on the secondary side of the three-phase transformer, V1 base is the rated voltage on the primary side of the three-phase transformer, and V2 base is the rated voltage on the secondary side of the three-phase transformer.

11. The device according to claim 8, characterized in that, the full matrix determination module is specifically used for: treating the three-phase transformer as three single-phase transformers, and determining the single-phase matrix of each single-phase transformer based on the resistance value, reactance value, first transformation ratio and second transformation ratio of the three-phase transformer; determining the full matrix of the three-phase transformer based on the single-phase matrices of the three single-phase transformers.

12. The device according to claim 8, characterized in that, the dimensionality reduction matrix determination module is further specifically used for: determining the wiring mode of the primary side of the three-phase transformer; when the wiring mode of the primary side of the three-phase transformer is star connection with the neutral point grounded, eliminating all the ix, iy and iz columns in the full matrix of the three-phase transformer; when the wiring mode of the primary side of the three-phase transformer is star connection, merging the iy and iz columns in the full matrix of the three-phase transformer into the ix column. The wiring method on the primary side of the three-phase transformer is the delta connection method. And when the line voltage phasor on the primary side points to the 12 o'clock position of the clock as the minute hand, and the line voltage phasor on the secondary side is at the 11 o'clock position of the clock, the ix column in the full matrix of the three-phase transformer is merged into the ic column, the iy column is merged into the ia column, and the iz column is merged into the ib column; The wiring method on the primary side of the three-phase transformer is the delta connection method. And when the line voltage phasor on the primary side points to the 12 o'clock position of the clock as the minute hand, and the line voltage phasor on the secondary side is at the 1 o'clock position of the clock, the ix column in the full matrix of the three-phase transformer is merged into the ib column, the iy column is merged into the ic column, and the iz column is merged into the ia column.

13. The device according to claim 12, characterized in that, The dimensionality reduction matrix determination module is further specifically used for: determine the wiring method on the secondary side of the three-phase transformer; When the wiring method on the secondary side of the three-phase transformer is the star connection method and the neutral point is grounded, all the ix, iy, and iz columns in the matrix obtained after dimensionality reduction of the primary side matrix are eliminated to obtain the dimensionality reduction matrix of the three-phase transformer; When the wiring method on the secondary side of the three-phase transformer is the star connection method, the iy and iz columns in the matrix obtained after dimensionality reduction of the primary side matrix are merged into the ix column to obtain the dimensionality reduction matrix of the three-phase transformer; When the wiring method on the secondary side of the three-phase transformer is the delta connection method, and when the line voltage phasor on the primary side points to the 12 o'clock position of the clock as the minute hand, and the line voltage phasor on the secondary side is at the 11 o'clock position of the clock, the ix column in the matrix obtained after dimensionality reduction of the primary side matrix is merged into the ic column, the iy column is merged into the ia column, and the iz column is merged into the ib column to obtain the dimensionality reduction matrix of the three-phase transformer; When the wiring method on the secondary side of the three-phase transformer is the delta connection method, and when the line voltage phasor on the primary side points to the 12 o'clock position of the clock as the minute hand, and the line voltage phasor on the secondary side is at the 1 o'clock position of the clock, the ix column in the matrix obtained after dimensionality reduction of the primary side matrix is merged into the ib column, the iy column is merged into the ic column, and the iz column is merged into the ia column to obtain the dimensionality reduction matrix of the three-phase transformer.

14. A computer-readable storage medium, characterized in that, The storage medium stores a computer program, and the computer program is used to execute the method according to any one of claims 1-7 above.

15. An electronic device, characterized in that, The electronic device includes: a processor; a memory for storing the executable instructions of the processor; The processor is used to read the executable instructions from the memory and execute the instructions to implement the method according to any one of claims 1-7 above.

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