A method, system, device, medium, and product for modeling a size step interface of a single phase transmission line

Abstract

The present application relates to the technical field of transient simulation modeling, and discloses a single-phase transmission line large-small step interface modeling method, system, device, medium and product. The total resistance of the single-phase transmission line is divided into two sections, and the sending-end voltage and the receiving-end voltage of the single-phase transmission line after two-section division are obtained, so that the equivalent pressure is carried out by using the equivalent electromagnetic equation, and the calculation complexity is greatly reduced. The initial electromagnetic transient equation of the single-phase transmission line is updated by using the sending-end voltage and the receiving-end voltage of the single-phase transmission line after two-section division, and the equivalent current source of the large-step interface and the equivalent current source of the small-step interface are determined. The equivalent current source of the large-step interface and the equivalent current source of the small-step interface are updated into the electromagnetic transient equation to carry out electromagnetic transient simulation modeling, and the precision of the electromagnetic transient modeling is improved.

Description

Technical Field

[0001] This invention relates to the field of transient simulation modeling technology, and in particular to a method, system, device, medium and product for modeling the large and small step interfaces of a single-phase transmission line. Background Technology

[0002] In recent years, with the integration of key entities such as large-scale offshore wind power, the scale and complexity of power systems have increased dramatically. Large-scale, high-proportion power electronic equipment has high switching frequency and large computational load, requiring very small simulation step sizes (typically 1-2 µs) to achieve relatively accurate simulations. However, traditional AC power grids do not require such small simulation step sizes, but rather larger ones, typically 50 µs. How to exchange simulation data between different step sizes in the same simulation system is a difficult problem.

[0003] Currently, electromagnetic transient modeling for asynchronous long interfaces suffers from low accuracy and high complexity. Summary of the Invention

[0004] In view of this, the present invention provides a method, system, device, medium and product for modeling interfaces with large and small step lengths of single-phase transmission lines, which solves the technical problems of low accuracy and high complexity when modeling electromagnetic transients of interfaces with different step lengths.

[0005] The first aspect of this invention provides a method for modeling the large and small step size interface of a single-phase transmission line, comprising:

[0006] The total resistance of the single-phase transmission line is divided into two segments, and the sending-end voltage and receiving-end voltage of the single-phase transmission line after the two segments are obtained.

[0007] The initial electromagnetic transient equation of the single-phase transmission line is updated based on the sending-end voltage and receiving-end voltage after the single-phase transmission line has been divided into two segments, so as to obtain the equivalent segmented electromagnetic transient equation of the single-phase transmission line.

[0008] Determine the equivalent current source of the large step length interface and the equivalent current source of the small step length interface in the equivalent segmented electromagnetic transient equation of the single-phase transmission line.

[0009] The equivalent current sources of the large step length interface and the small step length interface are updated into the equivalent piecewise electromagnetic transient equation of the single-phase transmission line. Electromagnetic transient simulation is performed using the updated equivalent piecewise electromagnetic transient equation to construct the electromagnetic transient simulation model of the single-phase transmission line.

[0010] Preferably, the step of dividing the total resistance of the single-phase transmission line into two segments and obtaining the sending-end voltage and receiving-end voltage of the single-phase transmission line after the two segments includes:

[0011] The total resistance of a single-phase transmission line is divided into two segments, and the two segments of resistance are connected in series to the sending end and receiving end of the single-phase transmission line, respectively, to form a segmented structure of the single-phase transmission line.

[0012] Based on the segmented structure of the single-phase transmission line, the initial voltage at the sending end and the initial voltage at the receiving end of the single-phase transmission line are divided to obtain the sending end voltage and the receiving end voltage of the single-phase transmission line after the two segments.

[0013] Preferably, the initial electromagnetic transient equation of the single-phase transmission line includes the sending-end voltage and receiving-end voltage of the single-phase transmission line;

[0014] The process of updating the initial electromagnetic transient equation of the single-phase transmission line based on the sending-end voltage and receiving-end voltage after the single-phase transmission line has undergone two segments, to obtain the equivalent segmented electromagnetic transient equation of the single-phase transmission line, includes:

[0015] The sending-end voltage and receiving-end voltage of the single-phase transmission line after two segments are replaced with the sending-end voltage and receiving-end voltage of the initial electromagnetic transient equation of the single-phase transmission line, and the equivalent segmented electromagnetic transient equation of the single-phase transmission line is obtained by combining like terms.

[0016] Preferably, the equivalent segmented electromagnetic transient equation of the single-phase transmission line is:

[0017]

[0018]

[0019] In the formula, , These are the branch currents at the sending and receiving ends of a single-phase transmission line, respectively. For the equivalent admittance of a single-phase transmission line, , These are the voltages at the sending and receiving ends of a single-phase transmission line, respectively. , These are the equivalent current sources at the sending and receiving ends of a single-phase transmission line, respectively. For a moment, For the duration of transmission;

[0020] in,

[0021]

[0022]

[0023]

[0024]

[0025] In the formula, , For single-phase transmission lines at The voltage at the sending and receiving ends at any given time. For impedance, The total resistance is... , For single-phase transmission lines at The branch currents at the sending and receiving ends at any given time. Inductance per unit length Capacitance per unit length.

[0026] Preferably, determining the equivalent current source of the large-step interface and the equivalent current source of the small-step interface in the equivalent segmented electromagnetic transient equation of the single-phase transmission line includes:

[0027] Linear interpolation is performed on the historical current sources of the two nearest adjacent large step length interfaces of the small step length interface to obtain the equivalent current source of the small step length interface. In this case, either the sending end or the receiving end of the single-phase transmission line is the large step length interface, and the other end is the small step length interface.

[0028] The equivalent current source of the large step-size interface is obtained by averaging the equivalent current source of the small step-size interface and the step size interval between the small step-size interface and the large step-size interface.

[0029] Preferably, the linear interpolation process is as follows:

[0030]

[0031] In the formula, For historical current interpolation of small step size interfaces, For small step size index, This refers to the number of steps required to move from a small stride to a large stride. For the current with a large step length in the historical current, For the previous large step size of the historical current, This is a simulation step size for a large step size.

[0032] Secondly, embodiments of this application also provide a large-step interface modeling system for single-phase transmission lines, comprising:

[0033] The segmentation module is used to divide the total resistance of a single-phase transmission line into two segments and obtain the sending-end voltage and receiving-end voltage of the single-phase transmission line after the two segments.

[0034] The transient equation update module is used to update the initial electromagnetic transient equation of the single-phase transmission line based on the sending-end voltage and receiving-end voltage after the single-phase transmission line has been divided into two segments, so as to obtain the equivalent segmented electromagnetic transient equation of the single-phase transmission line.

[0035] The current source equivalent module is used to determine the equivalent current source of the large step length interface and the equivalent current source of the small step length interface in the equivalent segmented electromagnetic transient equation of the single-phase transmission line.

[0036] The simulation modeling module is used to update the equivalent current sources of the large step length interface and the small step length interface into the equivalent piecewise electromagnetic transient equation of the single-phase transmission line, and to perform electromagnetic transient simulation using the updated equivalent piecewise electromagnetic transient equation to construct the electromagnetic transient simulation model of the single-phase transmission line.

[0037] Thirdly, embodiments of this application also provide an electronic device, which includes a memory and a processor. The memory stores a computer program, and when the computer program is executed by the processor, the processor performs the steps of the single-phase transmission line size step interface modeling method as described in the first aspect.

[0038] Fourthly, embodiments of this application also provide a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed, implements the steps of the single-phase transmission line large-step interface modeling method as described in the first aspect.

[0039] Fifthly, embodiments of this application also provide a computer program product, the computer program product including a computer program stored on a non-transitory computer-readable storage medium, the computer program including program instructions, wherein when the program instructions are executed by a computer, the computer performs the steps of the single-phase transmission line size step interface modeling method as described in the first aspect.

[0040] As can be seen from the above technical solutions, this invention divides the total resistance of a single-phase transmission line into two segments and obtains the sending-end voltage and receiving-end voltage of the single-phase transmission line after the two segments. This allows for the use of equivalent electromagnetic equations to calculate equivalent pressure, significantly reducing computational complexity. Furthermore, the initial electromagnetic transient equations of the single-phase transmission line are updated using the sending-end voltage and receiving-end voltage of the single-phase transmission line after the two segments. The equivalent current sources of the large-step interface and the small-step interface are then determined and updated into the electromagnetic transient equations for electromagnetic transient simulation modeling, thereby improving the accuracy of electromagnetic transient modeling. Attached Figure Description

[0041] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0042] Figure 1 This invention provides an application environment for a single-phase transmission line large-step interface modeling method.

[0043] Figure 2 A flowchart illustrating a method for modeling the large and small step sizes of a single-phase transmission line, as provided in an embodiment of the present invention;

[0044] Figure 3 A schematic diagram of a large and small step interface modeling system for a single-phase transmission line provided in an embodiment of the present invention;

[0045] Figure 4 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0046] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0047] The large and small step interface modeling method for single-phase transmission lines provided in this application embodiment can be applied to, for example... Figure 1In the application environment shown, the electromagnetic transient simulation software communicates with server 102 via a network. A data storage system can store the data that server 102 needs to process. The data storage system can be integrated onto server 102 or placed on a cloud or other network server. Server 102 divides the total resistance of the single-phase transmission line into two segments and obtains the sending-end voltage and receiving-end voltage of the single-phase transmission line after the two segments. Based on the sending-end voltage and receiving-end voltage of the single-phase transmission line after the two segments, it updates the initial electromagnetic transient equation of the single-phase transmission line to obtain the equivalent segmented electromagnetic transient equation of the single-phase transmission line. It determines the equivalent current source of the large-step interface and the equivalent current source of the small-step interface in the equivalent segmented electromagnetic transient equation of the single-phase transmission line. It updates the equivalent current source of the large-step interface and the equivalent current source of the small-step interface into the equivalent segmented electromagnetic transient equation of the single-phase transmission line, and uses the updated equivalent segmented electromagnetic transient equation to perform electromagnetic transient simulation, constructing an electromagnetic transient simulation model of the single-phase transmission line. Server 102 can be a standalone physical server, a server cluster or distributed system consisting of multiple physical servers, or a cloud server that provides cloud computing services.

[0048] like Figure 2 As shown, this application embodiment provides a method for modeling the large and small step size interface of a single-phase transmission line, which is applied to... Figure 1 Taking server 102 as an example, the explanation includes the following steps S1 to S4. Wherein:

[0049] Step S1: Divide the total resistance of the single-phase transmission line into two segments and obtain the sending-end voltage and receiving-end voltage of the single-phase transmission line after the two segments.

[0050] In this case, the total resistance of a single-phase transmission line is R, and the total resistance R is divided into two segments, resulting in a resistance of R / 2 for each segment.

[0051] Specifically, step S1, which involves dividing the total resistance of the single-phase transmission line into two segments and obtaining the sending-end voltage and receiving-end voltage of the single-phase transmission line after the two segments, includes:

[0052] Step S101: Divide the total resistance of the single-phase transmission line into two segments, and connect the two segments of resistance obtained after the two segments in series to the sending end and receiving end of the single-phase transmission line, respectively, to form a segmented structure of the single-phase transmission line.

[0053] Step S102: Based on the segmented structure of the single-phase transmission line, divide the initial voltage at the sending end and the initial voltage at the receiving end of the single-phase transmission line to obtain the sending end voltage and the receiving end voltage of the single-phase transmission line after two segments.

[0054] The sending-end voltage and receiving-end voltage of the single-phase transmission line after two segments are as follows:

[0055]

[0056] In the formula, , These are the voltages at the sending and receiving ends of a single-phase transmission line, respectively; that is, the sending and receiving voltages of the single-phase transmission line after it has been divided into two sections. , These are the initial voltages at the sending end and the receiving end of a single-phase transmission line, respectively. , These are the branch currents at the sending and receiving ends of a single-phase transmission line, respectively.

[0057] Step S2: Update the initial electromagnetic transient equation of the single-phase transmission line based on the sending-end voltage and receiving-end voltage after the single-phase transmission line has been divided into two segments, and obtain the equivalent segmented electromagnetic transient equation of the single-phase transmission line.

[0058] The initial electromagnetic transient equations are derived based on the principle of electromagnetic transient calculation in power systems. The initial electromagnetic transient equations are as follows:

[0059]

[0060] In the formula, , These are the branch currents at the sending and receiving ends of a single-phase transmission line, respectively. , These are the voltages at the sending and receiving ends of a single-phase transmission line, respectively. , These are the equivalent current sources at the sending and receiving ends of a single-phase transmission line, respectively. For a moment, For the time of dissemination, For impedance, The total resistance is... , For single-phase transmission lines at The branch currents at the sending and receiving ends at any given time. Inductance per unit length Capacitance per unit length.

[0061] The initial electromagnetic transient equations of a single-phase transmission line include the sending-end voltage and receiving-end voltage of the single-phase transmission line.

[0062] In some embodiments, step S2, updating the initial electromagnetic transient equation of the single-phase transmission line based on the sending-end voltage and receiving-end voltage after the single-phase transmission line has been segmented into two parts, to obtain the equivalent segmented electromagnetic transient equation of the single-phase transmission line, includes:

[0063] The sending-end voltage and receiving-end voltage of the single-phase transmission line after two segments are replaced with the sending-end voltage and receiving-end voltage of the initial electromagnetic transient equation of the single-phase transmission line. By combining like terms, the equivalent segmented electromagnetic transient equation of the single-phase transmission line is obtained.

[0064] The equivalent segmented electromagnetic transient equations for a single-phase transmission line are as follows:

[0065]

[0066]

[0067] In the formula, , These are the branch currents at the sending and receiving ends of a single-phase transmission line, respectively. For the equivalent admittance of a single-phase transmission line, , These are the voltages at the sending and receiving ends of a single-phase transmission line, respectively. , These are the equivalent current sources at the sending and receiving ends of a single-phase transmission line, respectively. For a moment, For the duration of transmission;

[0068] in,

[0069]

[0070]

[0071]

[0072]

[0073] In the formula, , For single-phase transmission lines at The voltage at the sending and receiving ends at any given time. For impedance, The total resistance is... , For single-phase transmission lines at The branch currents at the sending and receiving ends at any given time. Inductance per unit length Capacitance per unit length.

[0074] Step S3: Determine the equivalent current source of the large step length interface and the equivalent current source of the small step length interface in the equivalent segmented electromagnetic transient equation of the single-phase transmission line.

[0075] In this configuration, the sending end of the single-phase transmission line can be designated as a large-step interface, and the receiving end as a small-step interface; alternatively, the sending end can be designated as a small-step interface, and the receiving end as a large-step interface. When the sending end of the single-phase transmission line is a large-step interface and the receiving end is a small-step interface, the transmission time of the large-step interface is 50µs, and the transmission time of the small-step interface is 1µs. When the large-step interface completes one step, the small-step interface requires 50 small steps, which is the number of steps required for the small-step interface to reach the large-step interface.

[0076] Specifically, step S3, determining the equivalent current source for the large-step interface and the equivalent current source for the small-step interface in the equivalent segmented electromagnetic transient equation of the single-phase transmission line, includes:

[0077] Step S301: Perform linear interpolation based on the historical current sources of the two nearest adjacent large step interfaces of the small step interface to obtain the equivalent current source of the small step interface. Either the sending end or the receiving end of the single-phase transmission line is a large step interface, and the other end is a small step interface.

[0078] The linear interpolation process is as follows:

[0079]

[0080] In the formula, For historical current interpolation of small step size interfaces, For small step size index, This refers to the number of steps required to move from a small stride to a large stride. For the current with a large step length in the historical current, For the previous large step size of the historical current, This is a simulation step size for a large step size.

[0081] Step S302: Perform an average calculation based on the equivalent current source of the small step length interface and the step size interval between the small step length interface and the large step length interface to obtain the equivalent current source of the large step length interface.

[0082] The calculation of the equivalent current source with a large step size is obtained by averaging the historical currents of the number of steps (e.g., 50) required to run from a small step size to a large step size.

[0083] It is understandable that using an average value algorithm when calculating the equivalent current source with a large step size and a small step size, and using an interpolation algorithm when calculating the equivalent current source with a small step size and a large step size, can improve simulation accuracy.

[0084] Step S4: Update the equivalent current sources of the large step length interface and the small step length interface to the equivalent piecewise electromagnetic transient equation of the single-phase transmission line, and use the updated equivalent piecewise electromagnetic transient equation to perform electromagnetic transient simulation and construct the electromagnetic transient simulation model of the single-phase transmission line.

[0085] It is understandable that after obtaining the equivalent current sources for the large-step interface and the small-step interface, updating them into the equivalent piecewise electromagnetic transient equations of a single-phase transmission line allows for electromagnetic transient simulation using the updated equivalent piecewise electromagnetic transient equations, thus constructing an electromagnetic transient simulation model of a single-phase transmission line.

[0086] It should be noted that, in this embodiment, the total resistance of the single-phase transmission line is divided into two segments, and the sending-end voltage and receiving-end voltage of the single-phase transmission line after the two segments are obtained. The equivalent electromagnetic equation is then used to perform equivalent pressure, which greatly reduces the computational complexity. The initial electromagnetic transient equation of the single-phase transmission line is updated using the sending-end voltage and receiving-end voltage of the single-phase transmission line after the two segments, and the equivalent current sources of the large-step interface and the small-step interface are determined. The equivalent current sources of the large-step interface and the small-step interface are then used to update the electromagnetic transient equation for electromagnetic transient simulation modeling, thereby improving the accuracy of electromagnetic transient modeling.

[0087] Based on the same inventive concept, this application also provides a single-phase transmission line large-step interface modeling system for implementing the above-mentioned single-phase transmission line large-step interface modeling method.

[0088] The solution provided by this system is similar to the solution described in the above method. Therefore, the specific limitations of the one or more single-phase transmission line large and small step interface modeling system embodiments provided below can be found in the limitations of the single-phase transmission line large and small step interface modeling method above, and will not be repeated here.

[0089] like Figure 3 As shown in the illustration, this application also provides a single-phase transmission line large and small step interface modeling system, including:

[0090] The segmentation module 100 is used to divide the total resistance of a single-phase transmission line into two segments and obtain the sending-end voltage and receiving-end voltage of the single-phase transmission line after the two segments.

[0091] The transient equation update module 200 is used to update the initial electromagnetic transient equation of the single-phase transmission line based on the sending-end voltage and receiving-end voltage after the single-phase transmission line has been divided into two segments, so as to obtain the equivalent segmented electromagnetic transient equation of the single-phase transmission line.

[0092] The current source equivalent module 300 is used to determine the equivalent current source of the large step length interface and the equivalent current source of the small step length interface in the equivalent segmented electromagnetic transient equation of a single-phase transmission line.

[0093] The simulation modeling module 400 is used to update the equivalent current sources of the large step length interface and the small step length interface into the equivalent piecewise electromagnetic transient equation of the single-phase transmission line. The updated equivalent piecewise electromagnetic transient equation is used to perform electromagnetic transient simulation and construct the electromagnetic transient simulation model of the single-phase transmission line.

[0094] In some embodiments, the segmentation module 100 is used to divide the total resistance of the single-phase transmission line into two segments, and connect the two segments of line resistance obtained after the two segments in series to the sending end and receiving end of the single-phase transmission line, respectively, to form a segmented structure of the single-phase transmission line; according to the segmented structure of the single-phase transmission line, the initial voltage of the sending end and the initial voltage of the receiving end of the single-phase transmission line are divided to obtain the sending end voltage and the receiving end voltage of the single-phase transmission line after the two segments.

[0095] In some embodiments, the initial electromagnetic transient equation of a single-phase transmission line includes the sending-end voltage and receiving-end voltage of the single-phase transmission line.

[0096] The transient equation update module 200 is used to replace the sending-end voltage and receiving-end voltage of the single-phase transmission line after two segments with the sending-end voltage and receiving-end voltage of the initial electromagnetic transient equation of the single-phase transmission line, and obtain the equivalent segmented electromagnetic transient equation of the single-phase transmission line by combining like terms.

[0097] In some embodiments, the equivalent segmented electromagnetic transient equations of a single-phase transmission line are:

[0098]

[0099]

[0100] In the formula, , These are the branch currents at the sending and receiving ends of a single-phase transmission line, respectively. For the equivalent admittance of a single-phase transmission line, , These are the voltages at the sending and receiving ends of a single-phase transmission line, respectively. , These are the equivalent current sources at the sending and receiving ends of a single-phase transmission line, respectively. For a moment, For the duration of transmission;

[0101] in,

[0102]

[0103]

[0104]

[0105]

[0106] In the formula, , For single-phase transmission lines at The voltage at the sending and receiving ends at any given time. For impedance, The total resistance is... , For single-phase transmission lines at The branch currents at the sending and receiving ends at any given time. Inductance per unit length Capacitance per unit length.

[0107] In some embodiments, the current source equivalent module 300 is used to perform linear interpolation based on the historical current sources of the two nearest adjacent large step interfaces of the small step interface to obtain the equivalent current source of the small step interface, wherein either the sending end or the receiving end of the single-phase transmission line is a large step interface and the other end is a small step interface.

[0108] The equivalent current source of the large step-size interface is obtained by averaging the equivalent current source of the small step-size interface and the step size interval between the small step-size interface and the large step-size interface.

[0109] In some embodiments, the linear interpolation process is as follows:

[0110]

[0111] In the formula, For historical current interpolation of small step size interfaces, For small step size index, This refers to the number of steps required to move from a small stride to a large stride. For the current with a large step length in the historical current, For the previous large step size of the historical current, Simulated step size for large step size

[0112] like Figure 4 As shown, this application embodiment also provides an electronic device. The electronic device 10 includes a memory 20 and a processor 30. The memory 20 stores a computer program. When the computer program is executed by the processor 30, the processor 30 performs the steps of the single-phase transmission line size step interface modeling method as described in any of the above embodiments.

[0113] This application also provides a computer-readable storage medium storing a computer program thereon, which, when executed, implements the steps of the single-phase transmission line large-step interface modeling method as described in any of the above embodiments.

[0114] This application also provides a computer program product, which includes a computer program stored on a non-transitory computer-readable storage medium. The computer program includes program instructions, wherein when the program instructions are executed by a computer, the computer performs the steps of the single-phase transmission line size step interface modeling method as described in any of the above embodiments.

[0115] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, electronic devices, computer storage media, and computer program products described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0116] It should be noted that the terms "comprising" and "having" and any variations thereof in the specification, claims and accompanying drawings of this invention are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such processes, methods, products or devices.

[0117] In the several embodiments provided by this invention, it will be understood that each block in the flowchart or block diagram may represent a module, segment, or portion of code, which contains one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than those shown in the figures. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved.

[0118] In the embodiments provided by this invention, it should be understood that the disclosed systems, electronic devices, computer storage media, computer program products, and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the mutual coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection of devices or units may be electrical, mechanical, or other forms.

[0119] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0120] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0121] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for executing all or part of the steps of the methods described in the various embodiments of the present invention through a computer device (which may be a personal computer, a server, or a network device, etc.). The aforementioned storage medium includes: USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, optical disks, and other media capable of storing program code.

[0122] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for modeling the large and small step size interfaces of a single-phase transmission line, characterized in that, include: The total resistance of the single-phase transmission line is divided into two segments, and the sending-end voltage and receiving-end voltage of the single-phase transmission line after the two segments are obtained. The initial electromagnetic transient equation of the single-phase transmission line is updated based on the sending-end voltage and receiving-end voltage after the single-phase transmission line has been divided into two segments, so as to obtain the equivalent segmented electromagnetic transient equation of the single-phase transmission line. Determining the equivalent current sources for the large-step interface and the small-step interface in the equivalent segmented electromagnetic transient equations of the single-phase transmission line includes: Linear interpolation is performed on the historical current sources of the two nearest adjacent large step length interfaces of the small step length interface to obtain the equivalent current source of the small step length interface. In this case, either the sending end or the receiving end of the single-phase transmission line is the large step length interface, and the other end is the small step length interface. The equivalent current source of the large step-size interface is obtained by averaging the equivalent current source of the small step-size interface and the step size interval between the small step-size interface and the large step-size interface. The equivalent current sources of the large step length interface and the small step length interface are updated into the equivalent piecewise electromagnetic transient equation of the single-phase transmission line. Electromagnetic transient simulation is performed using the updated equivalent piecewise electromagnetic transient equation to construct the electromagnetic transient simulation model of the single-phase transmission line.

2. The method for modeling the large and small step interfaces of a single-phase transmission line according to claim 1, characterized in that, The step of dividing the total resistance of a single-phase transmission line into two segments and obtaining the sending-end voltage and receiving-end voltage of the single-phase transmission line after the two segments includes: The total resistance of a single-phase transmission line is divided into two segments, and the two segments of resistance are connected in series to the sending end and receiving end of the single-phase transmission line, respectively, to form a segmented structure of the single-phase transmission line. Based on the segmented structure of the single-phase transmission line, the initial voltage at the sending end and the initial voltage at the receiving end of the single-phase transmission line are divided to obtain the sending end voltage and the receiving end voltage of the single-phase transmission line after the two segments.

3. The method for modeling the large and small step interfaces of a single-phase transmission line according to claim 1, characterized in that, The initial electromagnetic transient equation of the single-phase transmission line includes the sending-end voltage and receiving-end voltage of the single-phase transmission line. The process of updating the initial electromagnetic transient equation of the single-phase transmission line based on the sending-end voltage and receiving-end voltage after the single-phase transmission line has been segmented into two parts, to obtain the equivalent segmented electromagnetic transient equation of the single-phase transmission line, includes: The sending-end voltage and receiving-end voltage of the single-phase transmission line after two segments are replaced with the sending-end voltage and receiving-end voltage of the initial electromagnetic transient equation of the single-phase transmission line, and the equivalent segmented electromagnetic transient equation of the single-phase transmission line is obtained by combining like terms.

4. The method for modeling the large and small step interfaces of a single-phase transmission line according to claim 1, characterized in that, The equivalent segmented electromagnetic transient equations of the single-phase transmission line are as follows: ； ； In the formula, , These are the branch currents at the sending and receiving ends of a single-phase transmission line, respectively. For the equivalent admittance of a single-phase transmission line, , These are the voltages at the sending and receiving ends of a single-phase transmission line, respectively. , These are the equivalent current sources at the sending and receiving ends of a single-phase transmission line, respectively. For a moment, For the duration of transmission; in, ； ； ； ； In the formula, , For single-phase transmission lines The voltage at the sending and receiving ends at any given time. For impedance, The total resistance is... , For single-phase transmission lines The branch currents at the sending and receiving ends at any given time. Inductance per unit length Capacitance per unit length.

5. The method for modeling the large and small step interfaces of a single-phase transmission line according to claim 1, characterized in that, The linear interpolation process is as follows: ； In the formula, For historical current interpolation of small step size interfaces, For small step size index, This represents the number of steps required to move from a small stride to a large stride. For the current with a large step length in the historical current, For the previous large step size of the historical current, This is a simulation step size for a large step size.

6. A modeling system for large and small step interfaces of a single-phase transmission line, characterized in that, include: The segmentation module is used to divide the total resistance of a single-phase transmission line into two segments and obtain the sending-end voltage and receiving-end voltage of the single-phase transmission line after the two segments. The transient equation update module is used to update the initial electromagnetic transient equation of the single-phase transmission line based on the sending-end voltage and receiving-end voltage after the single-phase transmission line has been divided into two segments, so as to obtain the equivalent segmented electromagnetic transient equation of the single-phase transmission line. The current source equivalent module is used to determine the equivalent current source of the large step length interface and the equivalent current source of the small step length interface in the equivalent segmented electromagnetic transient equation of the single-phase transmission line. Determining the equivalent current sources for the large-step interface and the small-step interface in the equivalent segmented electromagnetic transient equations of the single-phase transmission line includes: Linear interpolation is performed on the historical current sources of the two nearest adjacent large step length interfaces of the small step length interface to obtain the equivalent current source of the small step length interface. In this case, either the sending end or the receiving end of the single-phase transmission line is the large step length interface, and the other end is the small step length interface. The equivalent current source of the large step-size interface is obtained by averaging the equivalent current source of the small step-size interface and the step size interval between the small step-size interface and the large step-size interface. The simulation modeling module is used to update the equivalent current sources of the large step length interface and the small step length interface into the equivalent piecewise electromagnetic transient equation of the single-phase transmission line, and to perform electromagnetic transient simulation using the updated equivalent piecewise electromagnetic transient equation to construct the electromagnetic transient simulation model of the single-phase transmission line.

7. An electronic device, characterized in that, The electronic device includes a memory and a processor. The memory stores a computer program. When the computer program is executed by the processor, the processor performs the steps of the single-phase transmission line large-step interface modeling method as described in any one of claims 1-5.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed, it implements the steps of the single-phase transmission line large-step interface modeling method as described in any one of claims 1-5.

9. A computer program product, characterized in that, The computer program product includes a computer program stored on a non-transitory computer-readable storage medium, the computer program including program instructions, wherein when the program instructions are executed by a computer, the computer performs the steps of the large-step interface modeling method for a single-phase transmission line as described in any one of claims 1-5.

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