CN103714490B - Large power grid on-line data multi-thread rapid-integration method - Google Patents

Abstract

The invention provides a large power grid on-line data multi-thread rapid-integration method. The method comprises the steps of 1) reading and parsing various types of power grid data, storing the power grid data into an internal storage, and partitioning the internal storage according to the power grid data of power grid equipment of different types; 2) employing a parallel processing mode to associate the power grid equipment in each internal storage part after the partition with a corresponding topology node and establishing an association topology node list with respect to the topology nodes; and 3) zoning the topology nodes corresponding to the internal storage parts based on the partition of the internal storage, employing the parallel processing mode to conduct traversal analysis of the association topology node list of the topology nodes in each zone, performing topology island numbering of each topology node, eliminating dead topology islands, determining cared topology islands, conducting topology merging of all the zones of the topology nodes through tie lines among the zones of the topology nodes, and generating integrated power grid on-line data. The power grid data integration method provided by the invention is high in integration efficiency and rapid and highly efficient in processing procedure.

Description

Large power grid online data multithreading rapid integration method

Technical Field

The invention relates to the field of simulation analysis and calculation of an electric power system, in particular to a multithreading rapid integration method for online data of a large power grid.

Background

Digital simulation of an electric power system has become a main tool for planning, designing, dispatching, running and analyzing and researching the electric power system, and mathematical models of all elements of the electric power system and a full-system mathematical model formed by the mathematical models are the basis of the digital simulation of the electric power system. The model and the parameters are important determinants of the accuracy of the simulation result, and directly influence the decision scheme based on the model and the parameters.

The safe and reliable operation of the power grid has great significance for social and economic development. With the continuous expansion of the scale of a power grid, the continuous operation of a generator set, the continuous access of extra-high voltage power transmission and a renewable resource power supply, the wiring of the power grid is increasingly complex, the running condition of the power grid is increasingly complex, and the function of an online safety and stability assessment and early warning system is increasingly remarkable. The online safety and stability assessment and early warning system comprises the functions of calculation and analysis such as static stability analysis, transient stability analysis, dynamic stability analysis, stability margin assessment and the like, and all the calculation and analysis are based on complete calculation data, so online data integration is the basis of the online safety and stability assessment and early warning system. With the continuous popularization of the intelligent power grid dispatching technology support system, the scale of the online data integration model is larger and larger, so that the research of an accurate, efficient and rapid online data integration method is very necessary.

Traditional online data integration has two ideas: 1) integrating and generating trend data and stable data based on online measurement and model data and offline mode data of an EMS system; 2) and generating integrated tide data by utilizing online measurement and model data of the EMS system, and then generating corresponding stable data according to an offline dynamic parameter library. The generated integration trend in the thought 1) combines the characteristics of an online mode and an offline mode, so that the consistency with the online mode is not ensured, the error with an actual operation system is larger, and the thought is rarely used for realizing online data integration; concept 2) is the mainstream implementation of current online data integration.

The online data integration mostly comprises the steps of data reading, data analysis, topology generation, topology analysis and data calculation generation. Conventional online data integration includes several disadvantages: 1) the integration process adopts a serial structure, so that the speed is obviously reduced when the integrated data volume is large, and the requirements of high-efficiency and high-speed online application are difficult to meet; 2) data integration is simply a data transformation and does not address the presence of erroneous data in the online data and does not make a quantitative assessment of the quality of the online data.

Disclosure of Invention

In order to overcome the defects, the invention provides a method for quickly integrating online data multithreading of a large power grid, which comprises the following steps:

step 1, reading and analyzing various types of power grid data, storing the power grid data into a memory, and partitioning the memory corresponding to the power grid data of different types of power grid equipment;

step 2, associating the power grid equipment in each partitioned memory with a topology node in a parallel processing mode, and establishing an associated topology node table for the topology node;

step 3, partitioning the topology nodes corresponding to the internal memory of each block according to the partitioned blocks of the internal memory, and performing traversal analysis on the associated topology node table of the topology nodes of each partition by adopting a parallel processing mode;

numbering each topological node according to the topological island, removing topological dead islands and determining concerned topological islands;

and carrying out topology combination on the partitions of each topology node through a tie line between the topology node partitions to generate integrated online data of the power grid.

The invention provides a first preferred embodiment: the power grid data read in step 1 includes: the system comprises a station, a bus, a transformer, an alternating current circuit, a generator, a load, a parallel compensation device, a series compensation device, a current converter, a direct current circuit and a topological node;

the power grid data format is a CIM/E format or a CIM/XML format;

the process of reading and analyzing the power grid data comprises the following steps: and after the data file is mapped into the memory, the memory is partitioned according to different equipment types, and the memory in each block is processed in parallel by adopting an OpenMP multithreading parallel technology.

In a second preferred embodiment of the present invention: in the step 2, in the step of processing,

for a single-ended device, associating the single-ended device with the topology node;

for a double-end or multi-end device, after the double-end or multi-end device is associated with the topology nodes, generating the associated topology node table for each topology node;

the single-ended equipment comprises a bus, a generator and a load; the double-end or multi-end equipment comprises an alternating current line and a transformer.

In a third preferred embodiment of the present invention: in the step 3, a depth-first or breadth-first searching method is adopted to perform traversal analysis on the associated topological node table; and performing topology searching and numbering on each partition by adopting OpenMP multithread parallel calculation.

In a fourth preferred embodiment of the present invention: the step 3 of generating the integrated online data of the power grid comprises the following steps: outputting information of the topological nodes, the alternating current lines and the transformers in the region of interest to the power flow data in a PSD-BPA format; and if the generator dynamic parameter library is configured, outputting transient stability data in a PSD-BPA format.

In a fifth preferred embodiment of the present invention: after the topology merging in step 3, the method includes:

step 4, carrying out quality evaluation on the power grid data;

the quality evaluation process comprises the steps of searching for obvious errors existing in the concerned topological island, correcting the errors, and verifying whether the power grid data meet a power flow equation or not by adopting a parallel processing mode.

In a sixth preferred embodiment of the present invention: the step 4 of verifying whether the power grid data meets a power flow equation comprises:

step 401, judging whether the node meets power balance according to whether the calculated values of the active unbalanced power and the reactive unbalanced power of the node are 0;

step 402, constructing a two-node model of the line, and judging whether the line meets load flow verification according to the calculated value of the output power difference at the two ends of the line and the actually measured value of the output power difference at the two ends of the line;

step 403, constructing an equivalent circuit schematic diagram of the transformer, calculating a value of an output power difference of the primary side, the secondary side or the tertiary side of the transformer according to the calculated primary side current vector of the transformer and a current vector converted from the secondary side or the tertiary side to the primary side, and judging whether the transformer meets the power flow verification according to the calculated value of the output power difference and an actually measured value of the output power difference.

In a seventh preferred embodiment of the present invention: in step 401, the active unbalanced power and the reactive unbalanced power of the analysis node are calculated according to formulas (1) and (2):

${\mathrm{\ΔP}}_i=\underset{m=1}{\overset{n_G}{\Σ}}{P}_{Gm}+\underset{m=1}{\overset{n_L}{\Σ}}(-P_{Lm})+\underset{m=1}{\overset{n_B}{\Σ}}{P}_{Binm}---\left(1\right);$

${\mathrm{\ΔQ}}_i=\underset{m=1}{\overset{n_G}{\Σ}}{Q}_{Gm}+\underset{m=1}{\overset{n_L}{\Σ}}(-Q_{Lm})+\underset{m=1}{\overset{n_B}{\Σ}}{Q}_{Binm}+\underset{m=1}{\overset{n_{Sh}}{\Σ}}{Q}_{Shm}---\left(2\right);$

wherein, Δ P_iAnd Δ Q_iRespectively representing the active unbalanced power and the reactive unbalanced power of the node i; n is_GRepresenting the total number of generators on node i,representing the sum of the active outputs of all generators at node i,representing the sum of reactive powers of all generators on node i; n is_LRepresenting the number of load lines on node i,representing the sum of all the active loads on node i,represents the sum of all reactive loads on node i; n is_BIndicates the number of branches connected to node i,representing the sum of the injected real powers on node i of the branches connected to node i,representing the sum of injected reactive power of the branch connected with the node i on the node i; n is_ShIndicating the number of compensation devices on node i,representing the sum of the reactive power output of all reactive power compensation equipment on the node i;

in the step 402, the power flow of the line may be verified according to the formulas (3) and (4):

$\mathrm{\Δ}{\stackrel{\·}{S}}_i={\stackrel{\·}{S}}_i-{\stackrel{\·}{V}}_i\hat{I}-j\frac{1}{2}{V}_i^{2}B---\left(3\right);$

$\mathrm{\Δ}{\stackrel{\·}{S}}_j={\stackrel{\·}{S}}_j+{\stackrel{\·}{V}}_j\hat{I}-j\frac{1}{2}{V}_j^{2}B---\left(4\right);$

andrespectively the output power difference at the two ends of the circuit;andthe output power at two ends of the line respectively;andrespectively the voltage phasors at two ends of the line;for the current phasor of the line from side i to side j,r + jX is the impedance of the line,is thatThe conjugate phasor of (a); and B is the admittance of the line.

In an eighth preferred embodiment of the present invention: the transformer for power flow verification in step 403 includes a two-winding transformer and a three-winding transformer; verifying the value of the output power difference between the primary side and the secondary side of the transformer when the two-winding transformer performs power flow verification; verifying the values of the output power difference of the primary side, the secondary side and the tertiary side of the transformer when the three-winding transformer performs power flow verification;

the process of calculating the value of the output power difference between the primary side and the secondary side of the two-winding transformer in step 403 includes:

calculating the primary side current vector of the two-winding transformer and the current vector converted from the secondary side to the primary side according to the formulas (5) to (10)And

${\stackrel{\·}{V}}_1={\stackrel{\·}{I}}_1\[(R_1+{\mathrm{jX}}_1)+\frac{1}{G_m-{\mathrm{jB}}_m}\]-{{\stackrel{\·}{I}}_2}^{\′}\frac{1}{G_m-{\mathrm{jB}}_m}---\left(5\right);$

$-{\stackrel{\·}{V}}_2={{\stackrel{\·}{I}}_2}^{\′}\[({R_2}^{\′}+{{\mathrm{jX}}_2}^{\′})+\frac{1}{G_m-{\mathrm{jB}}_m}\]-{\stackrel{\·}{I}}_1\frac{1}{G_m-{\mathrm{jB}}_m}---\left(6\right);$

${{\stackrel{\·}{V}}_2}^{\′}=k{\stackrel{\·}{V}}_2---\left(7\right);$

${{\stackrel{\·}{I}}_2}^{\′}=\frac{1}{k}{\stackrel{\·}{I}}_2---\left(8\right);$

R₂'＝k²R₂(9)；

X₂'＝k²X₂(10)；

calculating the output power difference of the primary side and the secondary side of the two-winding transformer according to the formulas (11) and (12)Andthe value of (c):

$\mathrm{\Δ}{\stackrel{\·}{S}}_1={\stackrel{\·}{S}}_1-{\stackrel{\·}{V}}_1{\stackrel{\·}{I}}_1---\left(11\right);$

$\mathrm{\Δ}{\stackrel{\·}{S}}_2={\stackrel{\·}{S}}_2-{{\stackrel{\·}{V}}_2}^{\′}{{\stackrel{\·}{I}}_2}^{\′}---\left(12\right);$

is the phasor of the primary-side voltage of the transformer,andare respectively asAndthe amount of the conjugated phasor of (a),is the primary side current phasor of the transformer, R₁+jX₁Is the impedance of the primary winding of the transformer,is the phasor of the voltage at the secondary side of the transformer,is the current phasor of the secondary side of the transformer, R₂+jX₂Is the impedance of the secondary winding of the transformer, k is the primary-secondary side transformation ratio of the transformer,converting the secondary side voltage phasor of the transformer to the value of the primary side,for converting the current phasor of the secondary side of the transformer to the value of the primary side, R₂'+jX₂' is the value of the impedance of the secondary winding of the transformer, converted to the primary side, Y_m＝G_m-jB_mIs the excitation admittance of the transformer,the output power of the first and second sides of the transformer,the output power difference of the primary side and the secondary side of the transformer is respectively.

The benefits of the invention over the closest prior art include:

1. according to the method for quickly integrating the online data of the large power grid in the multithreading manner, the characteristics of each step of data integration are considered, the read power grid data are stored and then are partitioned according to different types of power grid equipment, and the subsequent processing processes of topology association and topology analysis are performed in parallel by adopting the multithreading technology according to the partitioned memories, so that the integration efficiency is improved, the processing process is quick and efficient, a foundation is laid for other applications of online safe and stable evaluation and early warning, and the basis is provided for the reliability of results.

2. The parallel processing is carried out by adopting the OpenMP multithreading parallel technology, the computing rapidity is ensured, the multithreading scheme is integrally designed by using the idea of electric network blocking according to the characteristic of natural blocking of an electric network, and the problem of conflict among threads is avoided.

3. The method has the advantages that the process of evaluating the quality of the power grid data is added, the accuracy of the on-line power grid data is considered from the perspective of a basic circuit equation, a quantitative index is given to the overall accuracy degree, and a basis of a basic data perspective is provided for evaluating the accuracy and credibility of other on-line high-grade application results.

Drawings

Fig. 1 is a flowchart of a multithreading fast integration method for online data of a large power grid according to the present invention;

FIG. 2 is a schematic diagram of a two-node model of a line;

fig. 3 is a schematic diagram of an equivalent circuit of a two-winding transformer.

Detailed Description

The following describes in further detail embodiments of the present invention with reference to the accompanying drawings.

The invention provides a method for quickly integrating online data multithreading of a large power grid, wherein a flow chart of the method is shown in figure 1, and as can be seen from figure 1, the method comprises the following steps:

step 1, reading and analyzing various types of power grid data, storing the power grid data into a memory, and partitioning the memory corresponding to the power grid data of different types of power grid equipment.

And 2, associating the power grid equipment in each partitioned memory with the topology nodes in a parallel processing mode, and establishing an associated topology node table for the topology nodes.

Step 3, partitioning the topology nodes corresponding to the internal memory of each block according to the blocks of the internal memory, performing traversal analysis on the associated topology node table of the topology nodes of each partition by adopting a parallel processing mode, numbering the topology islands of each topology node, removing the topology islands and determining the concerned topology islands; and topologically combining the partitions of each topological node through a tie line between the topological node partitions to generate integrated online data of the power grid.

In the step 1, the internal memory for storing the power grid data is partitioned according to different types of the power grid equipment, and in the subsequent steps 2 and 3, the processing processes of topology association and topology analysis are partitioned and processed in parallel according to the partitioned internal memory, so that the integration efficiency is improved, the processing processes are quick, efficient and accurate, a foundation is laid for other applications of online safety and stability evaluation and early warning, and a basis is provided for the reliability of results.

Further, the power grid data read in step 1 includes: plant, bus, transformer, ac line, generator, load, parallel compensation device, series compensation device, converter, dc line, topology node, etc. The grid data format may be a CIM/E format or a CIM/XML format. The process of reading and analyzing the power grid data comprises the following steps: and after the data file is mapped into the memory, the memory is partitioned according to different equipment types, and finally the memory in each block is processed by adopting an OpenMP multithreading parallel technology so as to realize the quick reading and analysis of the data file.

The parallel processing is carried out by adopting the OpenMP multithreading parallel technology, the computing rapidity is ensured, the multithreading scheme is integrally designed by using the idea of electric network blocking according to the characteristic of natural blocking of an electric network, and the problem of conflict among threads is avoided.

In step 2, for a single-ended device, associating the single-ended device with a topology node; for the double-end or multi-end equipment, after the double-end or multi-end equipment is associated with the topology nodes, an associated topology node table is generated for each topology node. Where single-ended devices include buses, generators, loads, etc., and double-ended or multi-ended devices include ac lines, transformers, etc.

In the step 3, a depth-first or breadth-first searching method can be adopted in the process of performing traversal analysis on the associated topology node table, and topology searching and numbering are performed on each partition by adopting OpenMP multithread parallel computing.

The step 3 of generating integrated power grid online data comprises the following steps: and outputting information such as topological nodes, alternating current lines, transformers and the like in the region of interest to the power flow data in a PSD-BPA format, and if a generator dynamic parameter library is configured, outputting transient stability data in the PSD-BPA format. According to the obtained data, functions of load flow calculation analysis, transient stability calculation analysis, short circuit current calculation analysis, dynamic stability calculation analysis and the like can be realized.

Preferably, after topology merging is performed in step 3 of the method for multithreading and fast integration of online data of a large power grid, the method provided by the invention may further include: and 4, evaluating the quality of the power grid data. The quality evaluation process comprises the steps of searching for obvious errors existing in the concerned topological island, correcting the errors, and verifying whether the power grid data meet a power flow equation or not by adopting a parallel processing mode.

Specifically, the step 4 of verifying whether the power grid data meets the power flow equation includes:

step 401, judging whether the node satisfies power balance according to whether the calculated values of the active unbalanced power and the reactive unbalanced power of the node are 0.

And 402, constructing a two-node model of the line, and judging whether the line meets the power flow verification according to the calculated value of the output power difference between the two ends of the line and the actually measured value of the output power difference between the two ends of the line.

Step 403, constructing an equivalent circuit schematic diagram of the transformer, calculating a value of an output power difference of the primary side, the secondary side or the tertiary side of the transformer according to the calculated primary side current vector of the transformer and the current vector converted from the secondary side or the tertiary side to the primary side, and judging whether the transformer meets the power flow verification according to the calculated value of the output power difference and the actually measured value of the output power difference.

Specifically, in step 401, the active unbalanced power and the reactive unbalanced power of the analysis node may be calculated according to formulas (1) and (2):

${\mathrm{\ΔP}}_i=\underset{m=1}{\overset{n_G}{\Σ}}{P}_{Gm}+\underset{m=1}{\overset{n_L}{\Σ}}(-P_{Lm})+\underset{m=1}{\overset{n_B}{\Σ}}{P}_{Binm}---\left(1\right);$

${\mathrm{\ΔQ}}_i=\underset{m=1}{\overset{n_G}{\Σ}}{Q}_{Gm}+\underset{m=1}{\overset{n_L}{\Σ}}(-Q_{Lm})+\underset{m=1}{\overset{n_B}{\Σ}}{Q}_{Binm}+\underset{m=1}{\overset{n_{Sh}}{\Σ}}{Q}_{Shm}---\left(2\right);$

wherein, Δ P_iAnd Δ Q_iRespectively representing the active unbalanced power and the reactive unbalanced power of the node i; n is_GRepresenting the total number of generators on node i,representing the sum of the active outputs of all generators at node i,representing the sum of reactive powers of all generators on node i; n is_LRepresenting the number of load lines on node i,representing the sum of all the active loads on node i,represents the sum of all reactive loads on node i; n is_BThe representation indicates the number of branches connected to node i,representing the sum of the injected real powers on node i of the branches connected to node i,representing the sum of injected reactive power of the branch connected with the node i on the node i; n is_ShIndicating the number of compensation devices on node i,representing the sum of the reactive power contributions of all the reactive power compensation devices at node i.

In step 402, the power flow of the line may be verified according to the formulas (3) and (4):

$\mathrm{\Δ}{\stackrel{\·}{S}}_i={\stackrel{\·}{S}}_i-{\stackrel{\·}{V}}_i\hat{I}-j\frac{1}{2}{V}_i^{2}B---\left(3\right);$

$\mathrm{\Δ}{\stackrel{\·}{S}}_j={\stackrel{\·}{S}}_j+{\stackrel{\·}{V}}_j\hat{I}-j\frac{1}{2}{V}_j^{2}B---\left(4\right);$

as shown in fig. 2, which is a schematic structural diagram of a two-node model of a line, as can be seen from fig. 2,andrespectively the output power difference at the two ends of the circuit;andthe output power at two ends of the line respectively;andrespectively the voltage phasors at two ends of the line;for the current phasor of the line from side i to side j,r + jX is the impedance of the line,is thatThe conjugate phasor of (a); b is the admittance of the circuit; wherein each value is a per-unit value.

The transformer for performing the power flow verification in step 403 includes a two-winding transformer and a three-winding transformer, the value of the output power difference between the primary side and the secondary side of the transformer needs to be verified when the two-winding transformer performs the power flow verification, and the value of the output power difference between the primary side, the secondary side and the tertiary side of the transformer needs to be verified when the three-winding transformer performs the power flow verification.

Taking a two-winding transformer as an example, fig. 3 is a schematic diagram of an equivalent circuit of the two-winding transformer, and in fig. 3,is the phasor of the primary-side voltage of the transformer,is the primary side current phasor of the transformer, R₁+jX₁Is the impedance of the primary winding of the transformer,is the phasor of the voltage at the secondary side of the transformer,is the current phasor of the secondary side of the transformer, R₂+jX₂Is the impedance of the secondary winding of the transformer, k is the primary-secondary side transformation ratio of the transformer,converting the secondary side voltage phasor of the transformer to the value of the primary side,for converting the current phasor of the secondary side of the transformer to the value of the primary side, R₂'+jX₂' is the value of the impedance of the secondary winding of the transformer, converted to the primary side, Y_m＝G_m-jB_mIs the excitation admittance of the transformer,the output power of the first and second sides of the transformer,the output power difference of the primary side and the secondary side of the transformer is respectively, wherein each value is a per-unit value.

In step 403, the primary side current vector of the two-winding transformer and the current vector converted from the secondary side to the primary side are calculated according to the formulas (5) to (10)And

${\stackrel{\·}{V}}_1={\stackrel{\·}{I}}_1\[(R_1+{\mathrm{jX}}_1)+\frac{1}{G_m-{\mathrm{jB}}_m}\]-{{\stackrel{\·}{I}}_2}^{\′}\frac{1}{G_m-{\mathrm{jB}}_m}---\left(5\right);$

$-{\stackrel{\·}{V}}_2={{\stackrel{\·}{I}}_2}^{\′}\[({R_2}^{\′}+{{\mathrm{jX}}_2}^{\′})+\frac{1}{G_m-{\mathrm{jB}}_m}\]-{\stackrel{\·}{I}}_1\frac{1}{G_m-{\mathrm{jB}}_m}---\left(6\right);$

${{\stackrel{\·}{V}}_2}^{\′}=k{\stackrel{\·}{V}}_2---\left(7\right);$

${{\stackrel{\·}{I}}_2}^{\′}=\frac{1}{k}{\stackrel{\·}{I}}_2---\left(8\right);$

R₂'＝k²R₂(9)；

X₂'＝k²X₂(10)；

calculating the output power difference between the primary side and the secondary side of the transformer according to the formulas (11) and (12)Andthe value of (c):

$\mathrm{\Δ}{\stackrel{\·}{S}}_1={\stackrel{\·}{S}}_1-{\stackrel{\·}{V}}_1{\hat{I}}_1---\left(11\right);$

$\mathrm{\Δ}{\stackrel{\·}{S}}_2={\stackrel{\·}{S}}_2-{{\stackrel{\·}{V}}_2}^{\′}{{\hat{I}}_2}^{\′}---\left(12\right);$

wherein,andare respectively asAndthe conjugate phasor of (a).

And 4, verifying whether the branch data in the online data meet a power flow equation, calculating the injection power deviation of the nodes connected with the branch power, outputting the branches and the nodes with larger deviation, and giving a data quality score.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solutions of the present invention and not for limiting the same, and although the present invention is described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: modifications and equivalents may be made to the embodiments of the invention without departing from the spirit and scope of the invention, which is to be covered by the claims.

Claims (7)

1. A large power grid online data multithreading rapid integration method is characterized by comprising the following steps:

step 1, reading and analyzing various types of power grid data, storing the power grid data into a memory, and partitioning the memory corresponding to the power grid data of different types of power grid equipment;

step 2, associating the power grid equipment in each partitioned memory with a topology node in a parallel processing mode, and establishing an associated topology node table for the topology node;

step 3, partitioning the topology nodes corresponding to the internal memory of each block according to the partitioned blocks of the internal memory, and performing traversal analysis on the associated topology node table of the topology nodes of each partition by adopting a parallel processing mode;

numbering each topological node according to the topological island, removing topological dead islands and determining concerned topological islands;

carrying out topology combination on the partitions of each topology node through a tie line between the partitions of the topology nodes to generate integrated online data of the power grid;

after the topology merging in step 3, the method includes:

step 4, carrying out quality evaluation on the power grid data;

the quality evaluation process comprises the steps of searching for obvious errors existing in the concerned topological island, correcting the errors, and verifying whether the power grid data meet a power flow equation or not in a parallel processing mode;

the step 4 of verifying whether the power grid data meets a power flow equation comprises:

step 401, judging whether the node meets power balance according to whether the calculated values of the active unbalanced power and the reactive unbalanced power of the node are 0;

step 402, constructing a two-node model of the line, and judging whether the line meets load flow verification according to the calculated value of the output power difference at the two ends of the line and the actually measured value of the output power difference at the two ends of the line;

step 403, constructing an equivalent circuit schematic diagram of the transformer, calculating a value of an output power difference of the primary side, the secondary side or the tertiary side of the transformer according to the calculated primary side current vector of the transformer and a current vector converted from the secondary side or the tertiary side to the primary side, and judging whether the transformer meets the power flow verification according to the calculated value of the output power difference and an actually measured value of the output power difference.

2. The method of claim 1, wherein the grid data read in step 1 comprises: the system comprises a station, a bus, a transformer, an alternating current circuit, a generator, a load, a parallel compensation device, a series compensation device, a current converter, a direct current circuit and a topological node;

the power grid data format is CIM/E format or CIM/XML format;

the process of reading and analyzing the power grid data comprises the following steps: and after the data file is mapped into the memory, the memory is partitioned according to different equipment types, and the memory in each block is processed in parallel by adopting an OpenMP multithreading parallel technology.

3. The method of claim 1, wherein in step 2,

for a single-ended device, associating the single-ended device with the topology node;

for a double-end or multi-end device, after the double-end or multi-end device is associated with the topology nodes, generating the associated topology node table for each topology node;

the single-ended equipment comprises a bus, a generator and a load; the double-end or multi-end equipment comprises an alternating current line and a transformer.

4. The method according to claim 1, wherein in the step 3, a depth-first or breadth-first search method is adopted to perform traversal analysis on the associated topology node table; and performing topology searching and numbering on each partition by adopting OpenMP multithread parallel calculation.

5. The method of claim 1, wherein generating the integrated grid online data in step 3 comprises: outputting information of the topological nodes, the alternating current lines and the transformers in the region of interest to the power flow data in a PSD-BPA format; and if the generator dynamic parameter library is configured, outputting transient stability data in a PSD-BPA format.

6. The method of claim 1,

in step 401, the active unbalanced power and the reactive unbalanced power of the analysis node are calculated according to formulas (1) and (2):

${\mathrm{\ΔP}}_i=\underset{m=1}{\overset{n_G}{\mathrm{\Σ}}}{P}_{Gm}+\underset{m=1}{\overset{n_L}{\mathrm{\Σ}}}(-P_{Lm})+\underset{m=1}{\overset{n_B}{\mathrm{\Σ}}}{P}_{Binm}---\left(1\right);$

${\mathrm{\ΔQ}}_i=\underset{m=1}{\overset{n_G}{\Σ}}{Q}_{Gm}+\underset{m=1}{\overset{n_L}{\Σ}}(-Q_{Lm})+\underset{m=1}{\overset{n_B}{\Σ}}{Q}_{Binm}+\underset{m=1}{\overset{n_{Sh}}{\Σ}}{Q}_{Shm}---\left(2\right);$

wherein, Δ P_iAnd Δ Q_iRespectively representing the active unbalanced power and the reactive unbalanced power of the node i; n is_GRepresenting the total number of generators on node i,representing the sum of the active outputs of all generators at node i,representing the sum of reactive powers of all generators on node i; n is_LRepresenting the number of load lines on node i,representing the sum of all the active loads on node i,represents the sum of all reactive loads on node i; n is_BIndicates the number of branches connected to node i,representing the sum of the injected real powers on node i of the branches connected to node i,representing the sum of injected reactive power of the branch connected with the node i on the node i; n is_ShIndicating the number of compensation devices on node i,representing the sum of the reactive power output of all reactive power compensation equipment on the node i;

in the step 402, the power flow of the line may be verified according to the formulas (3) and (4):

$\mathrm{\Δ}{\stackrel{\·}{S}}_i={\stackrel{\·}{S}}_i-{\stackrel{\·}{V}}_i\hat{I}-j\frac{1}{2}{V}_i^{2}B---\left(3\right);$

$\mathrm{\Δ}{\stackrel{\·}{S}}_j={\stackrel{\·}{S}}_j+{\stackrel{\·}{V}}_j\hat{I}-j\frac{1}{2}{V_j}^{2}B---\left(4\right);$

andrespectively the output power difference at the two ends of the circuit;andthe output power at two ends of the line respectively;andrespectively the voltage phasors at two ends of the line;for the current phasor of the line from side i to side j,r + jX is the impedance of the line,is thatThe conjugate phasor of (a); and B is the admittance of the line.

7. The method of claim 1, wherein the transformers for power flow verification in step 403 comprise a two-winding transformer and a three-winding transformer; verifying the value of the output power difference between the primary side and the secondary side of the transformer when the two-winding transformer performs power flow verification; verifying the values of the output power difference of the primary side, the secondary side and the tertiary side of the transformer when the three-winding transformer performs power flow verification;

the process of calculating the value of the output power difference between the primary side and the secondary side of the two-winding transformer in step 403 includes:

calculating the primary side current vector of the two-winding transformer and the current vector converted from the secondary side to the primary side according to the formulas (5) to (10)And

${\stackrel{\·}{V}}_1={\stackrel{\·}{I}}_1\[(R_1+{\mathrm{jX}}_1)+\frac{1}{G_m-{\mathrm{jB}}_m}\]-{{\stackrel{\·}{I}}_2}^{\′}\frac{1}{G_m-{\mathrm{jB}}_m}---\left(5\right);$

$-{\stackrel{\·}{V}}_2={{\stackrel{\·}{I}}_2}^{\′}\[({R_2}^{\′}+{{\mathrm{jX}}_2}^{\′})+\frac{1}{G_m-{\mathrm{jB}}_m}\]-{\stackrel{\·}{I}}_1\frac{1}{G_m-{\mathrm{jB}}_m}---\left(6\right);$

${{\stackrel{\·}{V}}_2}^{\′}=k{\stackrel{\·}{V}}_2---\left(7\right);$

${{\stackrel{\·}{I}}_2}^{\′}=\frac{1}{k}{\stackrel{\·}{I}}_2---\left(8\right);$

R₂'＝k²R₂(9)；

X₂'＝k²X₂(10)；

according to the formulae (11) and(12) calculating the output power difference between the primary side and the secondary side of the two-winding transformerAndthe value of (c):

$\mathrm{\Δ}{\stackrel{\·}{S}}_1={\stackrel{\·}{S}}_1-{\stackrel{\·}{V}}_1{\hat{I}}_1---\left(11\right);$

$\mathrm{\Δ}{\stackrel{\·}{S}}_2={\stackrel{\·}{S}}_2-{{\stackrel{\·}{V}}_2}^{\′}{{\hat{I}}_2}^{\′}---\left(12\right);$

is the phasor of the primary-side voltage of the transformer,andare respectively asAndthe amount of the conjugated phasor of (a),is the primary side current phasor of the transformer, R₁+jX₁Is the impedance of the primary winding of the transformer,is the phasor of the voltage at the secondary side of the transformer,is the current phasor of the secondary side of the transformer, R₂+jX₂Is the impedance of the secondary winding of the transformer, k is the primary-secondary side transformation ratio of the transformer,converting the secondary side voltage phasor of the transformer to the value of the primary side,for converting the current phasor of the secondary side of the transformer to the value of the primary side, R₂'+jX₂' is the value of the impedance of the secondary winding of the transformer, converted to the primary side, Y_m＝G_m-jB_mIs the excitation admittance of the transformer,the output power of the first and second sides of the transformer,the output power difference of the primary side and the secondary side of the transformer is respectively.