A calculation method and related device for solving the node voltage equation in electromagnetic transient simulation

Abstract

The present invention provides a method and a related device for calculating the solution time of a node voltage equation in an electromagnetic transient simulation. The method determines the number of non-zero elements and the number of zero elements in each column of an equivalent conductance matrix of the node voltage equation in the electromagnetic transient simulation; solves the element substitution time of the equivalent conductance matrix based on the number of non-zero elements in each column of the equivalent conductance matrix; solves the element solution time of the equivalent conductance matrix and the first matrix solution time of the equivalent conductance matrix after substitution; solves the second matrix solution time based on LU decomposition of the equivalent conductance matrix of the node voltage equation in the electromagnetic transient simulation; solves the order threshold of the equivalent conductance matrix based on the first matrix solution time and the second matrix solution time, selects a solution method with a shorter matrix solution time based on the order of the equivalent conductance matrix, and obtains the corresponding solution time. The present invention provides the matrix solution time of the equivalent conductivity matrix of the node voltage equation in electromagnetic transient simulation and the solution time of the equivalent conductivity matrix based on LU decomposition, which can quantify the computational performance of the node voltage equation and theoretically quantify the performance advantages and disadvantages of different solution methods.

Description

Technical Field

[0001] The present invention belongs to the technical field of electromagnetic transient real-time simulation, and in particular relates to a method for calculating the solution time of a node voltage equation in electromagnetic transient simulation and a related device. Background Art

[0002] Real-time power system simulation is an effective means of understanding power system characteristics, supporting power system research, planning, operation, production, and equipment manufacturing, and ensuring safe and reliable operation. Solving node voltage equations is a key step in real-time electromagnetic transient simulation technology. The equivalent conductance matrix in the node voltage equation is typically a sparse matrix. Existing solution methods are diverse, but the computational performance of the matrix has not been analyzed. This makes it impossible to theoretically quantify the performance advantages and disadvantages of different solution methods, nor is it possible to quantify the impact of the computational complexity of the node voltage equation on simulation performance in real-time electromagnetic transient simulation.

[0003] Therefore, how to obtain the solution time of the node voltage equation in electromagnetic transient simulation is an issue that needs attention. Summary of the Invention

[0004] In view of this, the present invention aims to provide a method and related device for calculating the solution time of node voltage equations in electromagnetic transient simulation, calculate the replacement time and solution time of equal-valued conductivity matrix elements in real-time electromagnetic transient simulation, quantify the calculation performance of node voltage equations, and facilitate real-time electromagnetic transient simulation of power systems.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] In a first aspect, the present invention provides a method for calculating the solution time of a node voltage equation in an electromagnetic transient simulation, comprising the following steps:

[0007] For the equivalent conductivity matrix of the node voltage equation in electromagnetic transient simulation, determine the number of non-zero elements and the number of zero elements in each column of the equivalent conductivity matrix;

[0008] Based on the number of non-zero elements in each column of the equivalent conductivity matrix, solve the element substitution time of the equivalent conductivity matrix;

[0009] For the equivalent conductance matrix after substitution, calculate the solution time of the equivalent conductance matrix elements and the solution time of the first matrix;

[0010] For the equivalent conductivity matrix of the node voltage equation in electromagnetic transient simulation, the solution time of the second matrix based on LU decomposition is calculated;

[0011] According to the solution time of the first matrix and the solution time of the second matrix, the order threshold of the equivalent conductance matrix is ​​solved, and according to the order of the equivalent conductance matrix, a solution method with a shorter matrix solution time is selected and the corresponding solution time is obtained.

[0012] Furthermore, the number of zero elements in the nth column of the equivalent conductance matrix is ​​recorded as k n , the number of non-zero elements in the nth column is recorded as nk n , then the equivalent conductivity matrix element replacement time is calculated according to the following formula:

[0013] T a =[n*min((n-1), (n-k1))+(n-1)*min((n-2), (n-k2))+……+2*1]*t a

[0014] Where, T a The time required to adjust the equivalent conductance matrix to an upper triangular matrix by element replacement, that is, the equivalent conductance matrix element replacement time; t a is the replacement time of a single element.

[0015] Furthermore, the solution time of the equivalent conductivity matrix elements is calculated as follows:

[0016] T e =n*(n+1)*t e / 2

[0017] Where, T e The time to solve for the equivalent conductivity matrix elements; t e is the solution time for a single element, and n is the number of element columns.

[0018] Furthermore, the first matrix solution time is calculated as follows:

[0019] T c = T a + T e

[0020] Where, T c is the time to solve the first matrix, T a is the replacement time of the equivalent conductivity matrix elements, T e Solve for the time for the equivalent conductance matrix elements.

[0021] Furthermore, the second matrix solution time is calculated according to the following formula:

[0022] T LU =n*(n+1)*t e

[0023] Where, T LU The time to solve the second matrix, te is the solution time for a single element, and n is the number of element columns.

[0024] Furthermore, the order threshold of the equivalent conductance matrix is ​​calculated as follows:

[0025] n k =[min((n-1), (n-k1))+(n-1) / n*min((n-2), (n-k2))+……+2 / n *1]*2t a / t e -1

[0026] Where n k is the order threshold of the equivalent conductivity matrix, n is the number of element columns, k n is the number of zero elements in the nth column of the equivalent conductance matrix, t a is the replacement time of a single element, t e is the solution time for a single element.

[0027] Furthermore, the expression of the equivalent conductance matrix is:

[0028] ;

[0029] Where A is the equivalent conductivity matrix of the node voltage equation in the electromagnetic transient real-time simulation calculation; g 11 is the first conductance of the first row in the equivalent conductance matrix; g 12 is the second conductance in the first row of the equivalent conductance matrix; g 1n is the nth conductance in the first row of the equivalent conductance matrix; g 21 is the first conductance in the second row of the equivalent conductance matrix; g 22 is the second conductance in the second row of the equivalent conductance matrix; g 2n is the nth conductance in the second row of the equivalent conductance matrix; g n1 is the first conductance of the nth row in the equivalent conductance matrix; g n2 is the second conductance in the nth row of the equivalent conductance matrix; g nn is the nth conductance in the nth row of the equivalent conductance matrix.

[0030] In a second aspect, the present invention provides a device for calculating the solution time of a node voltage equation in an electromagnetic transient simulation, comprising:

[0031] An element number calculation module is used to determine the number of non-zero elements and the number of zero elements in each column of the equivalent conductance matrix of the node voltage equation in the electromagnetic transient simulation;

[0032] A first time calculation module is used to solve the equivalent conductance matrix element replacement time based on the number of non-zero elements in each column of the equivalent conductance matrix;

[0033] A second time calculation module is used to solve the equivalent conductance matrix element solution time and the first matrix solution time for the replaced equivalent conductance matrix;

[0034] A third time calculation module is used to solve the second matrix solution time based on LU decomposition for the equivalent conductance matrix of the node voltage equation in the electromagnetic transient simulation;

[0035] The order threshold solving module is used to solve the order threshold of the equivalent conductance matrix according to the solution time of the first matrix and the solution time of the second matrix, select the solution method with less matrix solution time according to the order of the equivalent conductance matrix, and obtain the corresponding solution time.

[0036] Accordingly, the present invention further provides a computer device, comprising a processor and a memory:

[0037] The memory is used to store computer programs and send instructions of the computer programs to the processor;

[0038] The processor executes the method for calculating the solution time of a node voltage equation in electromagnetic transient simulation according to the instructions of the computer program as described in the first aspect.

[0039] Accordingly, the present invention also provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the method for calculating the solution time of a node voltage equation in an electromagnetic transient simulation as described in the first aspect is implemented.

[0040] In summary, the present invention provides a method and related device for calculating the solution time of a node voltage equation in an electromagnetic transient simulation. The method determines the number of non-zero elements and the number of zero elements in each column of the equivalent conductivity matrix for the node voltage equation in the electromagnetic transient simulation; solves the equivalent conductivity matrix element substitution time based on the number of non-zero elements in each column of the equivalent conductivity matrix; solves the equivalent conductivity matrix element solution time and the first matrix solution time for the replaced equivalent conductivity matrix; solves the second matrix solution time based on LU decomposition for the equivalent conductivity matrix of the node voltage equation in the electromagnetic transient simulation; solves the order threshold of the equivalent conductivity matrix based on the first matrix solution time and the second matrix solution time, selects a solution method with a shorter matrix solution time based on the order of the equivalent conductivity matrix, and obtains the corresponding solution time. The present invention provides the matrix solution time of the equivalent conductivity matrix of the node voltage equation in electromagnetic transient simulation and the solution time of the equivalent conductivity matrix based on LU decomposition, which can quantify the computational performance of the node voltage equation and theoretically quantify the performance advantages and disadvantages of different solution methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0042] Figure 1 A flowchart of a method for calculating the solution time of a node voltage equation in an electromagnetic transient simulation provided by an embodiment of the present invention;

[0043] Figure 2 A block diagram of a device for calculating the solution time of a node voltage equation in an electromagnetic transient simulation provided by an embodiment of the present invention;

[0044] Figure 3 A block diagram of a computer device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0045] In order to make the purposes, features, and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0046] See also Figure 1 This embodiment provides a method for calculating the solution time of a node voltage equation in an electromagnetic transient simulation, comprising the following steps:

[0047] S1: Determine the number of non-zero elements and zero elements in each column of the equivalent conductivity matrix of the node voltage equation in the electromagnetic transient simulation;

[0048] S2: Based on the number of non-zero elements in each column of the equivalent conductivity matrix, solve the element replacement time of the equivalent conductivity matrix;

[0049] S3: For the equivalent conductivity matrix after substitution, the solution time of the equivalent conductivity matrix elements and the first matrix solution time are calculated;

[0050] S4: Solve the second matrix solution time based on LU decomposition for the equivalent conductivity matrix of the node voltage equation in electromagnetic transient simulation;

[0051] S5: According to the solution time of the first matrix and the solution time of the second matrix, the order threshold of the equivalent conductance matrix is ​​solved, and according to the order of the equivalent conductance matrix, a solution method with a shorter matrix solution time is selected and the corresponding solution time is obtained.

[0052] It should be noted that electromagnetic transient processes primarily refer to the changes in the electric and magnetic fields, and the corresponding voltages and currents, within each component. The primary purpose of electromagnetic transient simulation is to analyze and calculate the transient overvoltages and overcurrents that may occur after a fault or operation. This allows for the rational design of related power equipment based on the resulting transient overvoltages and overcurrents, determines the safe operation of existing equipment, and investigates appropriate restrictions and protective measures. Furthermore, electromagnetic transient analysis is often required to study the operating principles of new fast-acting relay protection devices, fault point detection principles, and electromagnetic interference.

[0053] The equivalent conductance matrix of this embodiment is generated based on the Norton equivalent law to obtain the accompanying circuits of each component (capacitor, inductor) according to the system's connection relationship. The equivalent conductance matrix is ​​a symmetrical square matrix. The order n of the equivalent conductance matrix is ​​equal to the number of nodes in the power network. The diagonal elements are the self-admittances, which are the sum of the admittances of the branches directly connected to the nodes. An ideal voltage source is equivalent to a short circuit (Z = 0), and an ideal current source is equivalent to an open circuit (Z = ∞). Actual power sources are represented by a combination of an ideal power source and an impedance. The off-diagonal elements are the mutual admittances, which are the inverse of the sum of the admittances of the branches directly connecting two nodes.

[0054] In this embodiment, the number of nonzero elements and zero elements in each column of the equivalent conductance matrix for the node voltage equation in electromagnetic transient simulation is first determined. This determines the element permutation time required to convert the equivalent conductance matrix into an upper triangular matrix through element permutation. The equivalent conductance matrix element solution time and the first matrix solution time are then calculated for the permuted equivalent conductance matrix. The first matrix solution time is the solution time for the equivalent conductance matrix. Furthermore, this embodiment also determines the second matrix solution time based on LU decomposition for the equivalent conductance matrix for the node voltage equation in electromagnetic transient simulation. The order threshold of the equivalent conductance matrix is ​​determined based on the two matrix solution times. Based on the order threshold, a suitable solution method for the obtained equivalent conductance matrix can be determined. This solution method corresponds to the first matrix solution time or the second matrix solution time, thereby determining the solution time for the node voltage equation in electromagnetic transient simulation.

[0055] This embodiment provides a method for calculating the solution time of node voltage equations in electromagnetic transient simulations. This method provides the matrix solution time for the equivalent conductance matrix of the node voltage equations in electromagnetic transient simulations, as well as the solution time for the equivalent conductance matrix based on LU decomposition. This method can quantify the computational performance of the node voltage equations and theoretically quantify the performance advantages and disadvantages of different solution methods. Furthermore, this method provides a method for calculating the order threshold of the equivalent conductance matrix of the node voltage equations in electromagnetic transient simulations, which can quantify the performance advantages and disadvantages of different solution methods and determine the applicable scope of different solution methods, thereby improving the computational performance of real-time electromagnetic transient simulations.

[0056] In a preferred embodiment of the present invention, the equivalent conductance matrix of the node voltage equation in the electromagnetic transient simulation is:

[0057] ;

[0058] Where A is the equivalent conductivity matrix of the node voltage equation in the electromagnetic transient real-time simulation calculation; g 11 is the first conductance of the first row in the equivalent conductance matrix; g 12 is the second conductance in the first row of the equivalent conductance matrix; g 1n is the nth conductance in the first row of the equivalent conductance matrix; g 21 is the first conductance in the second row of the equivalent conductance matrix; g 22 is the second conductance in the second row of the equivalent conductance matrix; g 2n is the nth conductance in the second row of the equivalent conductance matrix; g n1 is the first conductance of the nth row in the equivalent conductance matrix; g n2 is the second conductance in the nth row of the equivalent conductance matrix; g nn is the nth conductance in the nth row of the equivalent conductance matrix;

[0059] The number of zero elements in the first column of the equivalent conductance matrix is ​​recorded as k1, and the number of non-zero elements in the first column is recorded as n-k1; the number of zero elements in the second column is recorded as k2, and the number of non-zero elements in the first column is recorded as n-k2; the number of zero elements in the nth column is recorded as k n , the number of non-zero elements in the first column is recorded as n- k n .

[0060] In a preferred embodiment of the present invention, based on the number of non-zero elements in each column of the equivalent conductance matrix, the equivalent conductance matrix is ​​adjusted to an upper triangular matrix by element replacement.

[0061]

[0062] Where B is the permuted upper triangular matrix; b11 is the first conductance of the first row in the permuted upper triangular matrix; b12 is the second conductance of the first row in the permuted upper triangular matrix; b1n is the nth conductance of the first row in the permuted upper triangular matrix; b22 is the second conductance of the second row in the permuted upper triangular matrix; b2n is the nth conductance of the second row in the permuted upper triangular matrix; bnn is the nth conductance of the nth row in the permuted upper triangular matrix; all elements below the diagonal in the permuted upper triangular matrix are 0.

[0063] The time required to adjust the equivalent conductivity matrix to an upper triangular matrix by element substitution is:

[0064] T a =[n*min((n-1), (n-k1))+(n-1)*min((n-2), (n-k2))+……+2*1]*t a

[0065] Among them, T a The time required to adjust the equivalent conductance matrix to an upper triangular matrix by element replacement; t a is the replacement time of a single element.

[0066] In a preferred embodiment of the present invention, after the equivalent conductance matrix is ​​adjusted to an upper triangular matrix by element substitution, the time required to solve the equivalent conductance matrix elements after substitution is:

[0067] T e =(1+2+3+……+n)*t e =n*(n+1)*t e / 2

[0068] Among them, T e The time to solve for the equivalent conductivity matrix elements; t e is the solution time for a single element.

[0069] In a preferred embodiment of the present invention, for the equivalent conductance matrix after substitution, the matrix solution time of the equivalent conductance matrix is:

[0070] T c = T a + T e =[n*min((n-1), (n-k1))+(n-1)*min((n-2), (n-k2))+……+2*1]*t a +n*(n+1)*t e / 2

[0071] In a preferred embodiment of the present invention, the time required to solve the equivalent conductivity matrix based on LU decomposition is:

[0072] TLU=2*(1+2+3+……+n)*te=n*(n+1)*te

[0073] Among them, T LU t is the time to solve the equivalent conductivity matrix based on LU decomposition; e is the solution time for a single element.

[0074] In a preferred embodiment of the present invention, let T c =T LU , the solved n k That is the order threshold of the equivalent conductance matrix:

[0075] [n*min((n-1),(n-k1))+(n-1)*min((n-2), (n-k2))+……+2*1]*t a +n*(n+1)*t e / 2= n*(n+1)*t e

[0076] [n*min((n-1), (n-k1))+(n-1)*min((n-2), (n-k2))+……+2*1]*t a = n*(n+1)*t e / 2

[0077] Right now:

[0078] n k =[min((n-1), (n-k1))+(n-1) / n*min((n-2), (n-k2))+……+2 / n *1]*2t a / t e -1

[0079] In this embodiment, a solution method with a shorter solution time is selected based on the relationship between the actual order of the equivalent conductance matrix and the order threshold.

[0080] Based on the same inventive concept, an embodiment of the present application further provides a device for calculating the time required to solve a node voltage equation in an electromagnetic transient simulation, which implements the aforementioned method for calculating the time required to solve a node voltage equation in an electromagnetic transient simulation. The solution provided by this system is similar to the solution described in the aforementioned method. Therefore, the specific limitations of the embodiment of the device for calculating the time required to solve a node voltage equation in an electromagnetic transient simulation provided below can be found in the limitations of the method for calculating the time required to solve a node voltage equation in an electromagnetic transient simulation described above, and will not be further elaborated here.

[0081] See also Figure 2This embodiment provides a device for calculating the solution time of a node voltage equation in an electromagnetic transient simulation, characterized by comprising:

[0082] An element number calculation module is used to determine the number of non-zero elements and the number of zero elements in each column of the equivalent conductance matrix of the node voltage equation in the electromagnetic transient simulation;

[0083] A first time calculation module is used to solve the equivalent conductance matrix element replacement time based on the number of non-zero elements in each column of the equivalent conductance matrix;

[0084] A second time calculation module is used to solve the equivalent conductance matrix element solution time and the first matrix solution time for the equivalent conductance matrix after substitution;

[0085] A third time calculation module is used to solve the second matrix solution time based on LU decomposition for the equivalent conductance matrix of the node voltage equation in the electromagnetic transient simulation;

[0086] The order threshold solving module is used to solve the order threshold of the equivalent conductance matrix according to the solution time of the first matrix and the solution time of the second matrix, select a solution method with a shorter matrix solution time according to the order of the equivalent conductance matrix, and obtain the corresponding solution time.

[0087] Those skilled in the art can clearly understand that, for the convenience and brevity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In actual applications, the above-mentioned functions can be distributed and completed by different functional units and modules as needed, that is, the internal structure of the system can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiment can be integrated into one processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of this application. The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here.

[0088] Reference Figure 3 An embodiment of the present invention further provides a computer device 3, comprising: a memory 302, a processor 301, and a computer program 303 stored in the memory 302. When the computer program 303 is executed on the processor 301, a method for calculating the solution time of the node voltage equation in the electromagnetic transient simulation as described in any one of the above methods is implemented.

[0089] The computer device 3 may be a desktop computer, a notebook computer, a PDA, a cloud server or other computing devices. The computer device 3 may include, but is not limited to, a processor 301 and a memory 302. Those skilled in the art will understand that Figure 3 This is merely an example of the computer device 3 and does not constitute a limitation on the computer device 3 . The computer device 3 may include more or fewer components than shown in the figure, or a combination of certain components, or different components. For example, the computer device 3 may also include input and output devices, network access devices, etc.

[0090] The processor 301 may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. A general-purpose processor may be a microprocessor or any conventional processor.

[0091] In some embodiments, the memory 302 may be an internal storage unit of the computer device 3, such as a hard drive or memory of the computer device 3. In other embodiments, the memory 302 may also be an external storage device of the computer device 3, such as a plug-in hard drive, a Smart Media Card (SMC), a Secure Digital (SD) card, a flash memory card, etc. equipped on the computer device 3. Furthermore, the memory 302 may include both an internal storage unit of the computer device 3 and an external storage device. The memory 302 is used to store an operating system, application programs, a boot loader, data, and other programs, such as the program code of the computer program. The memory 302 may also be used to temporarily store data that has been output or is about to be output.

[0092] An embodiment of the present invention further provides a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, the method for calculating the solution time of the node voltage equation in the electromagnetic transient simulation as described in any one of the above methods is implemented.

[0093] In this embodiment, if the integrated unit is implemented as a software functional unit and sold or used as a standalone product, it can be stored in a computer-readable storage medium. Based on this understanding, the present application can implement all or part of the process steps in the above-mentioned method embodiments by using a computer program to instruct the relevant hardware. The computer program can be stored in a computer-readable storage medium. When executed by a processor, the computer program can implement the steps of each of the above-mentioned method embodiments. The computer program includes computer program code, which can be in source code form, object code form, executable file, or some intermediate form. The computer-readable medium can include at least: any entity or device capable of carrying computer program code to a camera / terminal device, recording medium, computer memory, read-only memory (ROM), random access memory (RAM), electric carrier signals, telecommunication signals, and software distribution media. Examples include USB flash drives, removable hard drives, magnetic disks, or optical disks. In some jurisdictions, based on legislation and patent practice, computer-readable media cannot be electric carrier signals or telecommunication signals.

[0094] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant description of other embodiments.

[0095] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0096] In the embodiments disclosed in the present application, it should be understood that the disclosed devices / terminal equipment and methods can be implemented in other ways. For example, the device / terminal equipment embodiments described above are merely schematic. For example, the division of the modules or units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0097] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for calculating the solution time of node voltage equations in electromagnetic transient simulation, characterized in that: The steps include: For an equivalent conductance matrix of a node voltage equation in an electromagnetic transient simulation, determining the number of non-zero elements and the number of zero elements in each column of the equivalent conductance matrix; Solving the element replacement time of the equivalent conductance matrix based on the number of non-zero elements in each column of the equivalent conductance matrix; For the equivalent conductance matrix after substitution, solving the equivalent conductance matrix element solution time and the first matrix solution time; For the equivalent conductivity matrix of the node voltage equation in electromagnetic transient simulation, the solution time of the second matrix based on LU decomposition is calculated; According to the first matrix solution time and the second matrix solution time, the order threshold of the equivalent conductance matrix is ​​solved, and according to the order of the equivalent conductance matrix, a solution method with a shorter matrix solution time is selected to obtain a corresponding solution time.

2. The method for calculating the solution time of the node voltage equation in electromagnetic transient simulation according to claim 1, characterized in that: The number of zero elements in the nth column of the equivalent conductance matrix is ​​recorded as k n , the number of non-zero elements in the nth column is recorded as nk n , then the equivalent conductivity matrix element replacement time is calculated according to the following formula: T a =[n*min((n-1), (n-k1))+(n-1)*min((n-2), (n-k2))+……+2*1]*t a； Where, T a The time required to adjust the equivalent conductance matrix to an upper triangular matrix by element replacement, that is, the element replacement time of the equivalent conductance matrix; t a is the replacement time of a single element.

3. The method for calculating the solution time of the node voltage equation in electromagnetic transient simulation according to claim 1, characterized in that: The solution time of the equivalent conductivity matrix elements is calculated according to the following formula: T e =n*(n+1)*t e / 2; Where, T e The time for solving the equivalent conductivity matrix elements; t e is the solution time for a single element, and n is the number of element columns.

4. The method for calculating the solution time of the node voltage equation in electromagnetic transient simulation according to claim 1, characterized in that: The first matrix solution time is calculated according to the following formula: T c = T a + T e； Where, T c is the time to solve the first matrix, T a is the equivalent conductance matrix element replacement time, T e Solve for the time for the equivalent conductance matrix element.

5. The method for calculating the solution time of the node voltage equation in electromagnetic transient simulation according to claim 1, characterized in that: The second matrix solution time is calculated according to the following formula: T LU =n*(n+1)*t e； Where, T LU The time to solve the second matrix, t e is the solution time for a single element, and n is the number of element columns.

6. The method for calculating the solution time of the node voltage equation in electromagnetic transient simulation according to claim 1, characterized in that: The order threshold of the equivalent conductance matrix is ​​calculated according to the following formula: n k =[min((n-1), (n-k1))+(n-1) / n*min((n-2), (n-k2))+……+2 / n *1]*2t a / t e -1; Where n k is the order threshold of the equivalent conductivity matrix, n is the number of element columns, k n is the number of zero elements in the nth column of the equivalent conductance matrix, t a is the replacement time of a single element, t e is the solution time for a single element.

7. The method for calculating the solution time of the node voltage equation in electromagnetic transient simulation according to claim 1, characterized in that: The expression of the equivalent conductance matrix is: ； Where A is the equivalent conductance matrix of the node voltage equation in the electromagnetic transient real-time simulation calculation; g 11 is the first conductance of the first row in the equivalent conductance matrix; g 12 is the second conductance in the first row of the equivalent conductance matrix; g 1n is the nth conductance in the first row of the equivalent conductance matrix; g 21 is the first conductance in the second row of the equivalent conductance matrix; g 22 is the second conductance in the second row of the equivalent conductance matrix; g 2n is the nth conductance in the second row of the equivalent conductance matrix; g n1 is the first conductance of the nth row in the equivalent conductance matrix; g n2 is the second conductance in the nth row of the equivalent conductance matrix; g nn is the nth conductance in the nth row of the equivalent conductance matrix.

8. A device for calculating the solution time of node voltage equations in electromagnetic transient simulation, characterized in that: include: An element number calculation module is used to determine the number of non-zero elements and the number of zero elements in each column of the equivalent conductance matrix of the node voltage equation in the electromagnetic transient simulation; A first time calculation module is used to solve the equivalent conductance matrix element replacement time based on the number of non-zero elements in each column of the equivalent conductance matrix; A second time calculation module is used to solve the equivalent conductance matrix element solution time and the first matrix solution time for the equivalent conductance matrix after substitution; A third time calculation module is used to solve the second matrix solution time based on LU decomposition for the equivalent conductance matrix of the node voltage equation in the electromagnetic transient simulation; The order threshold solving module is used to solve the order threshold of the equivalent conductance matrix according to the solution time of the first matrix and the solution time of the second matrix, select a solution method with a shorter matrix solution time according to the order of the equivalent conductance matrix, and obtain the corresponding solution time.

9. A computer device, characterized in that: The device includes a processor and a memory: The memory is used to store the computer program and send instructions of the computer program to the processor; The processor executes the method for calculating the solution time of a node voltage equation in electromagnetic transient simulation according to any one of claims 1 to 7 according to the instructions of the computer program.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, which, when executed by a processor, implements a method for calculating the solution time of a node voltage equation in electromagnetic transient simulation according to any one of claims 1 to 7.

Images