A method of electromagnetic transient simulation for suppressing numerical oscillation and related apparatus

Abstract

The application provides an electromagnetic transient simulation method and related device for inhibiting numerical oscillation, and belongs to the technical field of electromagnetic transient simulation. The method comprises the following steps: obtaining a resonant frequency of a first modal PI model established in advance and a sampling frequency of electromagnetic transient simulation; when the sampling frequency meets the condition of being not significantly greater than the resonant frequency, a new second modal PI model is obtained based on the first modal PI model in a mode of connecting a resistance in series on a capacitor, the second modal PI model inhibits numerical oscillation through the mode of connecting the resistance in series; parameters of the resistance connected in series in the second modal PI model are set; and in the process of electromagnetic transient simulation, electromagnetic transient simulation is performed based on the second modal PI model corresponding to each simulation time step. The application constructs a new modal PI model through the mode of connecting a resistance in series on the capacitor of the original modal PI model, utilizes the resistance to provide an additional damping effect, and then inhibits numerical oscillation in the simulation process, thereby improving simulation stability.

Description

Technical Field

[0001] The present invention belongs to the technical field of electromagnetic transient simulation, and in particular relates to an electromagnetic transient simulation method and related devices for suppressing numerical oscillation. Background Art

[0002] In the modeling and simulation of power transmission lines, the PI model is often used to simulate traveling wave transmission. However, the natural response of the PI model often exhibits the undamped oscillation of an ideal LC circuit, especially in the case of short transmission lines, where the resonant frequency is high. Traditional methods are unable to effectively suppress this oscillation, resulting in numerical oscillations in the simulation results, affecting the accuracy and stability of the system.

[0003] Real-time simulation systems require models to be calculated within a short time step to ensure that the simulation results can reflect the dynamic behavior of the system in real time. However, modal PI models of high-frequency short transmission lines are prone to numerical oscillation under such conditions, affecting the stability and accuracy of real-time simulations. Summary of the Invention

[0004] In view of this, the present invention aims to provide an electromagnetic transient simulation method and related device for suppressing numerical oscillations, so as to solve the problem that the modal PI model of high-frequency short transmission lines is prone to numerical oscillations.

[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 an electromagnetic transient simulation method for suppressing numerical oscillation, comprising the following steps:

[0007] Obtain the resonant frequency of the pre-established first modal PI model;

[0008] Get the sampling frequency of electromagnetic transient simulation;

[0009] When the sampling frequency satisfies the condition of not being significantly greater than the resonant frequency, a new second modal PI model is obtained based on the first modal PI model by connecting a resistor in series with the capacitor. The second modal PI model suppresses numerical oscillation by connecting the resistor in series.

[0010] Set the parameters of the series resistor in the second mode PI model;

[0011] During the electromagnetic transient simulation process, electromagnetic transient simulation is performed based on the second mode PI model corresponding to each simulation time step.

[0012] Furthermore, the parameters of the series resistor include a damping coefficient, which is determined according to the ratio of the resonant frequency to the sampling frequency, including:

[0013]

[0014] Where δ is the damping coefficient, is the resonant frequency, f sample is the sampling frequency.

[0015] Furthermore, the parameters of the series resistor also include the resistance value, which is calculated according to the following formula:

[0016]

[0017] Where R shm is the resistance value of the series resistor, δ is the damping coefficient of the series resistor, L m is the inductance value of the model, C m is the capacitance value of the model.

[0018] Furthermore, the resonant frequency is calculated as follows:

[0019]

[0020] Where, is the resonant frequency, L m is the inductance value, C m is the capacitance value.

[0021] Furthermore, the condition for not being significantly greater than is:

[0022]

[0023] Where, is the resonant frequency, f sample is the sampling frequency.

[0024] In a second aspect, the present invention provides an electromagnetic transient simulation device for suppressing numerical oscillations, comprising:

[0025] A parameter acquisition module is used to obtain the resonant frequency of the pre-established first modal PI model and the sampling frequency of the electromagnetic transient simulation;

[0026] A model updating module is configured to obtain a new second modal PI model based on the first modal PI model by connecting a resistor in series with the capacitor when the sampling frequency satisfies a condition that the sampling frequency is not significantly greater than the resonant frequency. The second modal PI model suppresses numerical oscillation by connecting the resistor in series.

[0027] A model setting module, used to set the parameters of the series resistor in the second modal PI model;

[0028] The simulation module is used to perform electromagnetic transient simulation based on the second mode PI model corresponding to each simulation time step during the electromagnetic transient simulation process.

[0029] Furthermore, the parameters of the series resistor include a damping coefficient, which is determined according to the ratio of the resonant frequency to the sampling frequency, including:

[0030]

[0031] Where δ is the damping coefficient, is the resonant frequency, f sample is the sampling frequency.

[0032] Furthermore, the parameters of the series resistors also include resistance values, which are calculated according to the following formula:

[0033]

[0034] Where R shm is the resistance value of the series resistor, δ is the damping coefficient of the series resistor, L m is the inductance value of the model, C m is the capacitance value of the model.

[0035] Accordingly, the present invention further provides a computer device, comprising a processor and a memory:

[0036] The memory is used to store computer programs and send instructions of the computer programs to the processor;

[0037] The processor executes the electromagnetic transient simulation method for suppressing numerical oscillation according to the instructions of the computer program.

[0038] 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 electromagnetic transient simulation for suppressing numerical oscillation according to the first aspect is implemented.

[0039] In summary, the present invention provides an electromagnetic transient simulation method and related device for suppressing numerical oscillations, including obtaining the resonant frequency of a pre-established first modal PI model; obtaining a sampling frequency for electromagnetic transient simulation; when the sampling frequency satisfies the condition of not being significantly greater than the resonant frequency, based on the first modal PI model, obtaining a new second modal PI model by connecting a resistor in series with a capacitor, wherein the second modal PI model suppresses numerical oscillations by means of a series resistor; setting the parameters of the series resistor in the second modal PI model; and during the electromagnetic transient simulation process, performing electromagnetic transient simulation based on the second modal PI model corresponding to each simulation time step. The present invention constructs a new second modal PI model by connecting a resistor in series with the capacitor of the original first modal PI model, utilizing the resistor to provide an additional damping effect, thereby suppressing numerical oscillations during the simulation process and improving simulation stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] 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.

[0041] Figure 1 A flowchart of an electromagnetic transient simulation method for suppressing numerical oscillation provided by an embodiment of the present invention;

[0042] Figure 2 A schematic diagram of a traditional PI model provided in an embodiment of the present invention;

[0043] Figure 3 A schematic diagram of a PI model with a series resistor provided in an embodiment of the present invention;

[0044] Figure 4 A block diagram of the composition of an electromagnetic transient simulation device for suppressing numerical oscillations provided by an embodiment of the present invention;

[0045] Figure 5 A block diagram of a computer device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0046] 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.

[0047] See also Figure 1-3 , Figure 1 The present invention shows a process of an electromagnetic transient simulation method for suppressing numerical oscillation; Figure 2 and 3 Schematic diagrams of a traditional modal PI model and a modal PI model with a series resistor according to the method of the present invention are shown respectively.

[0048] like Figure 1 As shown, this embodiment provides an electromagnetic transient simulation method for suppressing numerical oscillation, comprising the following steps:

[0049] S1: Obtain the resonant frequency of the pre-established first modal PI model.

[0050] It should be noted that, first, the system's resonant frequency information is extracted from the pre-established modal PI model of the power transmission line (i.e., the first modal PI model). This step is crucial for understanding the system's dynamic characteristics, as the resonant frequency is directly related to the oscillation phenomenon that may occur in the system under specific conditions.

[0051] By calculating the modal transmission time, characteristic impedance, inductance and capacitance in the modal domain, a modal PI model is established. Figure 2 As shown, each power transmission line includes an RLC (resistance R-inductance L-capacitance C) component.

[0052] S2: Get the sampling frequency of electromagnetic transient simulation.

[0053] It should be noted that the sampling frequency used for electromagnetic transient simulation has a direct impact on simulation accuracy and stability. Too high or too low a sampling frequency may cause simulation problems.

[0054] S3: When the sampling frequency satisfies the condition of not being significantly greater than the resonant frequency, a new second modal PI model is obtained based on the first modal PI model by connecting a resistor in series with the capacitor. The second modal PI model suppresses numerical oscillations by connecting the resistor in series.

[0055] It's important to note that when the sampling frequency is determined to be not significantly higher than the system's resonant frequency, this indicates a potential risk of numerical oscillation. To address this issue, a new second-mode PI model is created based on the original first-mode PI model by adding a resistor in series with the capacitor element. This modification introduces additional damping to the system, helping to suppress numerical oscillation during the simulation.

[0056] The structure of the second modal PI model is as follows Figure 3 As shown, a resistor R is connected in series with the capacitor of the model. sh .

[0057] S4: Set the parameters of the series resistor in the second modal PI model.

[0058] It’s important to note that optimizing the performance of the new model requires careful setting of the series resistor’s parameters. This involves determining the resistor value to achieve the best damping effect while minimizing changes to the system’s original characteristics.

[0059] S5: During the electromagnetic transient simulation process, the electromagnetic transient simulation is performed based on the second mode PI model corresponding to each simulation time step.

[0060] It should be noted that throughout the electromagnetic transient simulation process, the second-mode PI model, adjusted to the current system state, is used for calculations at each simulation time step. This ensures that the simulation reflects the system dynamics in real time and effectively suppresses numerical oscillations by continuously applying the model with series resistance, improving the reliability and accuracy of the simulation results.

[0061] This embodiment provides an electromagnetic transient simulation method for suppressing numerical oscillations. This method suppresses numerical oscillations by conditionally adding a resistor in series within a modal PI model. This method is particularly suitable for high-frequency, short transmission lines. This method can significantly improve the stability and accuracy of simulation results, particularly in real-time simulation systems.

[0062] In a preferred embodiment of the present invention, the resonant frequency of the modal PI model can be calculated using the following formula:

[0063]

[0064] Where, is the resonant frequency, L m is the inductance value, C m is the capacitance value.

[0065] In a preferred embodiment of the present invention, the sampling frequency f sample It can be calculated based on the simulation time step Δt:

[0066] f sample =1 / Δt.

[0067] In a preferred embodiment of the present invention, the condition of not significantly greater than is:

[0068]

[0069] Where, is the resonant frequency, f sample is the sampling frequency.

[0070] That is, if the sampling frequency f sample Not significantly greater than the resonant frequency Numerical oscillations may occur, where significantly greater than means If it is significantly greater than, then Figure 2 If it is not significantly greater than , then the method of the present invention is used, and a resistor is connected in series with the capacitor.

[0071] In a preferred embodiment of the present invention, the parameters of the series resistor include a damping coefficient, which is determined according to the ratio of the resonant frequency to the sampling frequency, including:

[0072]

[0073] Where δ is the damping coefficient, is the resonant frequency, f sample is the sampling frequency.

[0074] That is When , the damping coefficient δ=0;

[0075] when When , the damping coefficient δ=0.1;

[0076] when When , the damping coefficient is as follows:

[0077]

[0078] In a preferred embodiment of the present invention, the parameters of the series resistor also include a resistance value, which is calculated according to the following formula:

[0079]

[0080] Where R shm is the resistance value of the series resistor, δ is the damping coefficient of the series resistor, L m is the inductance value of the model, C m is the capacitance value of the model.

[0081] Simulations have shown that the added resistor effectively suppresses numerical oscillations, making the system's dynamic response more stable and accurate. This method, applied to a real-time simulation system, ensures stability and accuracy during the simulation by dynamically calculating and adjusting the resistor value at each simulation time step.

[0082] Based on the same inventive concept, an embodiment of the present application further provides an electromagnetic transient simulation device for suppressing numerical oscillations, which is used to implement the aforementioned electromagnetic transient simulation method for suppressing numerical oscillations. The solution provided by this device is similar to the solution described in the aforementioned method. Therefore, the specific limitations of the electromagnetic transient simulation device for suppressing numerical oscillations provided below can be found in the limitations of the electromagnetic transient simulation method for suppressing numerical oscillations described above and will not be further elaborated here.

[0083] See also Figure 4 This embodiment provides an electromagnetic transient simulation device for suppressing numerical oscillation, comprising:

[0084] A parameter acquisition module is used to obtain the resonant frequency of the pre-established first modal PI model and the sampling frequency of the electromagnetic transient simulation;

[0085] A model updating module is configured to obtain a new second modal PI model based on the first modal PI model by connecting a resistor in series with the capacitor when the sampling frequency satisfies a condition that the sampling frequency is not significantly greater than the resonant frequency. The second modal PI model suppresses numerical oscillation by connecting the resistor in series.

[0086] A model setting module, used to set the parameters of the series resistor in the second modal PI model;

[0087] The simulation module is used to perform electromagnetic transient simulation based on the second mode PI model corresponding to each simulation time step during the electromagnetic transient simulation process.

[0088] In a preferred embodiment of the present invention, the parameters of the series resistor include a damping coefficient, which is determined according to the ratio of the resonant frequency to the sampling frequency, including:

[0089]

[0090] Where δ is the damping coefficient, is the resonant frequency, f sample is the sampling frequency.

[0091] In a preferred embodiment of the present invention, the parameters of the series resistors also include resistance values, which are calculated according to the following formula:

[0092]

[0093] Where R shm is the resistance value of the series resistor, δ is the damping coefficient of the series resistor, L m is the inductance value of the model, C m is the capacitance value of the model.

[0094] 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.

[0095] Reference Figure 5 An embodiment of the present invention further provides a computer device 1, comprising: a memory 12 and a processor 11 and a computer program 13 stored in the memory 12. When the computer program 13 is executed on the processor 11, an electromagnetic transient simulation method for suppressing numerical oscillations as described in any one of the above methods is implemented.

[0096] The computer device 1 can be a desktop computer, a notebook computer, a PDA, a cloud server or other computing devices. The computer device 1 can include, but is not limited to, a processor 11 and a memory 12. Those skilled in the art will understand that Figure 5 This is merely an example of the computer device 1 and does not constitute a limitation on the computer device 1 . The computer device 1 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 1 may also include input and output devices, network access devices, etc.

[0097] The processor 11 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.

[0098] In some embodiments, the memory 12 may be an internal storage unit of the computer device 1, such as a hard disk or memory of the computer device 1. In other embodiments, the memory 12 may also be an external storage device of the computer device 1, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc. equipped on the computer device 1. Furthermore, the memory 12 may also include both an internal storage unit of the computer device 1 and an external storage device. The memory 12 is used to store an operating system, application programs, a boot loader (BootLoader), data, and other programs, such as the program code of the computer program. The memory 12 may also be used to temporarily store data that has been output or is about to be output.

[0099] An embodiment of the present invention further provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the electromagnetic transient simulation method for suppressing numerical oscillation as described in any one of the above methods is implemented.

[0100] In this embodiment, 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 present application implements all or part of the process of the above-mentioned method embodiment by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by a processor, it 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 at least include: any entity or device capable of carrying computer program code to the camera / terminal device, recording medium, computer memory, read-only memory (ROM), random access memory (RAM), electric carrier signal, telecommunication signal, and software distribution medium. For example, a USB flash drive, mobile hard drive, magnetic disk, or optical disk. In some jurisdictions, based on legislation and patent practice, computer-readable media cannot be electric carrier signals or telecommunication signals.

[0101] 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.

[0102] 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.

[0103] 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.

[0104] 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. An electromagnetic transient simulation method for suppressing numerical oscillation, characterized in that: The steps include: Obtain the resonant frequency of the pre-established first modal PI model; Get the sampling frequency of electromagnetic transient simulation; When the sampling frequency satisfies a condition of not being significantly greater than the resonant frequency, a new second modal PI model is obtained based on the first modal PI model by connecting a resistor in series with a capacitor, wherein the second modal PI model suppresses numerical oscillation by connecting the resistor in series; Setting parameters of the series resistor in the second modal PI model; During the electromagnetic transient simulation process, performing electromagnetic transient simulation based on the second modal PI model corresponding to each simulation time step; The parameters of the series resistor include a damping coefficient, which is determined according to the ratio of the resonant frequency to the sampling frequency, including: ； Where, is the damping coefficient, is the resonant frequency, is the sampling frequency.

2. The electromagnetic transient simulation method for suppressing numerical oscillation according to claim 1, characterized in that: The parameters of the series resistor also include a resistance value, which is calculated according to the following formula: ； Where, is the resistance value of the series resistor, is the damping coefficient of the series resistor, is the inductance value of the model, is the capacitance value of the model.

3. The electromagnetic transient simulation method for suppressing numerical oscillation according to claim 1, characterized in that: The resonant frequency is calculated according to the following formula: ； Where, is the resonant frequency, is the inductance value, is the capacitance value.

4. The electromagnetic transient simulation method for suppressing numerical oscillation according to claim 1, characterized in that: The condition of not being significantly greater than is: ； Where, is the resonant frequency, is the sampling frequency.

5. An electromagnetic transient simulation device for suppressing numerical oscillation, characterized in that: include: A parameter acquisition module is used to obtain the resonant frequency of the pre-established first modal PI model and the sampling frequency of the electromagnetic transient simulation; a model updating module, configured to, when the sampling frequency satisfies a condition that the sampling frequency is not significantly greater than the resonant frequency, obtain a new second modal PI model based on the first modal PI model by connecting a resistor in series with the capacitor, wherein the second modal PI model suppresses numerical oscillation by connecting the resistor in series; A model setting module, used to set parameters of the series resistor in the second modal PI model; A simulation module, configured to perform electromagnetic transient simulation based on the second modal PI model corresponding to each simulation time step during an electromagnetic transient simulation process; The parameters of the series resistors include a damping coefficient, which is determined according to the ratio of the resonant frequency to the sampling frequency, including: ； Where, is the damping coefficient, is the resonant frequency, is the sampling frequency.

6. The electromagnetic transient simulation device for suppressing numerical oscillation according to claim 5, characterized in that: The parameters of the resistors in series also include resistance value, which is calculated according to the following formula: ； Where, is the resistance value of the series resistor, is the damping coefficient of the series resistor, is the inductance value of the model, is the capacitance value of the model.

7. 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 electromagnetic transient simulation method for suppressing numerical oscillation according to any one of claims 1 to 5 according to instructions of the computer program.

8. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the electromagnetic transient simulation method for suppressing numerical oscillation according to any one of claims 1 to 5 is implemented.

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