An electromagnetic transient simulation method and system for the inertia decay effect in power systems

Abstract

This invention discloses an electromagnetic transient simulation method and system for the inertia decay effect of a power system. The method includes: constructing a power system containing new energy units and conventional units in an electromagnetic transient simulation platform, acquiring historical operating data of the power system, constructing an inertia dynamic equation and embedding it into the electromagnetic transient simulation platform, obtaining the current frequency of the power system by solving the inertia dynamic equation; constructing a frequency offset extreme value discrimination function, calculating the frequency offset extreme value at the current frequency, and determining whether the current equivalent inertia of the current system is insufficient based on the frequency offset extreme value; if the current equivalent inertia of the current system is insufficient, obtaining the compensation power of the power system based on the current frequency of the power system, and performing power compensation on the power system.

Description

Technical Field

[0001] This invention belongs to the field of new energy technology, and more specifically, relates to an electromagnetic transient simulation method and system for the inertia decay effect of a power system. Background Technology

[0002] Existing power system frequency stability analysis and control technologies are mainly based on the mechanical inertia characteristics of traditional synchronous generators, using inertia response to buffer frequency fluctuations caused by power imbalances in the system. In power grids dominated by traditional thermal power units, synchronous generators have relatively large physical rotational inertia, resulting in smoother frequency changes and a strong self-stabilizing capability of the system.

[0003] However, with the large-scale integration of new energy sources, especially asynchronous power sources such as wind and solar power, the total mechanical inertia of the system has decreased significantly, resulting in an inertia "missing" phenomenon. New energy sources do not possess the mechanical rotational inertia of traditional synchronous machines, and their output power fluctuates significantly and has a fast dynamic response, increasing the difficulty of grid frequency regulation. Existing traditional frequency dynamic models cannot accurately reflect the dynamic changes in inertia over time and with the proportion of new energy sources. The inertia constant is usually assumed to be a fixed value, ignoring the weakening effect of new energy penetration on system inertia, making it difficult to meet the frequency stability analysis needs under high new energy penetration conditions. Summary of the Invention

[0004] To address the above technical problems, this invention proposes an electromagnetic transient simulation method for the inertia decay effect of power systems, comprising:

[0005] Step 101: Construct a power system including new energy units and conventional units in the electromagnetic transient simulation platform, obtain historical operating data of the power system, construct an inertia dynamic equation and embed it into the electromagnetic transient simulation platform, and obtain the current frequency of the power system by solving the inertia dynamic equation.

[0006] Step 102: Construct a frequency offset extreme value discrimination function, calculate the frequency offset extreme value at the current frequency, and determine whether the current equivalent inertia of the current system is insufficient based on the frequency offset extreme value;

[0007] Step 103: If the current equivalent inertia of the current system is insufficient, the compensation power of the power system is obtained according to the current frequency of the power system, and power compensation is performed on the power system.

[0008] Furthermore, the historical operating data includes: the rated frequency of the power system, the initial equivalent inertia constant of the power system, the acquisition time window of the historical operating data, the absolute value of the peak acceleration of the power system at the historical frequency, the rated inertia of the power system, and the historical frequency of the power system.

[0009] Furthermore, the dynamic equation for inertia includes:

[0010] ,

[0011] in, For time Equivalent inertia constant of the power system at that time For time The frequency of the power system The damping coefficient is... For time The difference between the total power generated and the total power of the load in a power system.

[0012] Furthermore, computation time Equivalent inertia constant of power system include:

[0013] ,

[0014] in, Let be the initial equivalent inertia constant of the power system. For time The cumulative inertia dissipation factor reflects the degree to which the proportion of new energy sources weakens the equivalent inertia of the power system. For time The cumulative value of frequency oscillations reflects the degree to which frequency fluctuations suppress the effectiveness of the equivalent inertia of the power system.

[0015] Furthermore, time Cumulative inertia dissipation factor include:

[0016] ,

[0017] in, For time The proportion of new energy power output at that time For time The impact of renewable energy output on the decay of the equivalent inertia of the power system is used to measure the rate at which the equivalent inertia of the power system decreases when renewable energy output increases.

[0018] Furthermore, time Time-frequency oscillation cumulative value include:

[0019] ,

[0020] in, The time window for collecting historical operational data. For time Historical frequencies of the power system It represents the absolute value of the peak acceleration at historical frequencies of the power system.

[0021] Furthermore, the calculation of the frequency offset extremes at the current frequency includes:

[0022] ,

[0023] in, For time Time frequency offset extreme value, The rated power of the power system. This is the rated inertia of the power system.

[0024] Furthermore, determining whether the current system's current equivalent inertia is insufficiently supported based on the frequency offset extreme value includes: when time Time-frequency offset extreme value When the offset exceeds a preset threshold, the current equivalent inertia of the current system is insufficient to support it.

[0025] Furthermore, after power compensation is performed on the power system, steps 101 to 103 are executed iteratively until the difference between the total power generated and the total power of the load in the power system is less than a preset difference threshold.

[0026] This invention also proposes an electromagnetic transient simulation system for the inertia decay effect of a power system, comprising:

[0027] The frequency acquisition module is used to construct a power system including new energy units and conventional units in the electromagnetic transient simulation platform, acquire the historical operating data of the power system, construct the inertia dynamic equation and embed it into the electromagnetic transient simulation platform, and obtain the current frequency of the power system by solving the inertia dynamic equation.

[0028] The frequency offset extreme value calculation module is used to construct a frequency offset extreme value discrimination function, calculate the frequency offset extreme value at the current frequency, and determine whether the current equivalent inertia of the current system is insufficient based on the frequency offset extreme value.

[0029] The compensation module is used to obtain the compensation power of the power system based on the current frequency of the power system and perform power compensation on the power system if the current equivalent inertia of the current system is insufficient.

[0030] In summary, the technical solutions conceived by this invention have the following beneficial effects compared with the prior art:

[0031] The technical solution of this invention introduces a virtual inertia compensation strategy, combined with the system's reference power. Rated frequency The settings enable real-time suppression of frequency change rate and dynamic control of active power injection, thereby effectively improving the inertial response capability of the power system under disturbances, slowing down the frequency drop rate, improving frequency stability, and reducing the risk of system instability due to insufficient inertia. Attached Figure Description

[0032] Figure 1 This is a flowchart of the method in Embodiment 1 of the present invention;

[0033] Figure 2 This is a system structure diagram of Embodiment 2 of the present invention. Detailed Implementation

[0034] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0035] The method provided by this invention can be implemented in a terminal environment that may include one or more of the following components: a processor, a storage medium, and a display screen. The storage medium stores at least one instruction, which is loaded and executed by the processor to implement the method described in the following embodiments.

[0036] A processor may include one or more processing cores. The processor uses various interfaces and lines to connect various parts of the terminal, and performs various functions and processes data by running or executing instructions, programs, code sets or instruction sets stored in the storage medium, and by calling data stored in the storage medium.

[0037] Storage media can include random access memory (RAM) or read-only memory (ROM). Storage media can be used to store instructions, programs, code, code sets, or instructions.

[0038] The display screen is used to show the user interface of each application.

[0039] In addition, those skilled in the art will understand that the structure of the terminal described above does not constitute a limitation on the terminal. The terminal may include more or fewer components, or combine certain components, or have different component arrangements. For example, the terminal may also include radio frequency circuits, input units, sensors, audio circuits, power supplies, and other components, which will not be described in detail here.

[0040] Example 1

[0041] like Figure 1 As shown, this embodiment proposes an electromagnetic transient simulation method for the inertia decay effect of a power system, including:

[0042] Step 101: Construct a power system including new energy units and conventional units in the electromagnetic transient simulation platform, obtain historical operating data of the power system, construct an inertia dynamic equation and embed it into the electromagnetic transient simulation platform, and obtain the current frequency of the power system by solving the inertia dynamic equation.

[0043] Preferably, a disturbance is applied to the power system in the electromagnetic transient simulation platform, for example:

[0044] Unit tripping (the generator suddenly stops, the power system has less generating power → frequency drops);

[0045] Large load input or output (sudden increase or decrease in load → causing power imbalance);

[0046] Rapid fluctuations in renewable energy output (such as sudden drops in wind speed or changes in sunlight causing short-term changes in wind / solar power output);

[0047] Rapid power regulation of energy storage or frequency regulation units (artificially injecting a known power change to test the power system response).

[0048] This generates time The difference between the total generated power and the total load power in the power system .

[0049] Specifically, the historical operating data includes: the rated frequency of the power system, the initial equivalent inertia constant of the power system, the acquisition time window of the historical operating data, the absolute value of the peak acceleration of the power system at the historical frequency, the rated inertia of the power system, and the historical frequency of the power system.

[0050] Specifically, the inertia dynamic equation includes:

[0051] ,

[0052] in, For time Equivalent inertia constant of the power system at that time For time The frequency of the power system The damping coefficient is... For time The difference between the total power generated and the total power of the load in a power system.

[0053] Preferred, for example, damping coefficient It can be .

[0054] Specifically, calculation time Equivalent inertia constant of power system include:

[0055] ,

[0056] in, Let be the initial equivalent inertia constant of the power system. For time The cumulative inertia dissipation factor reflects the degree to which the proportion of new energy sources weakens the equivalent inertia of the power system. For time The cumulative value of frequency oscillations reflects the degree to which frequency fluctuations suppress the effectiveness of the equivalent inertia of the power system.

[0057] Specifically, time Cumulative inertia dissipation factor include: ,

[0058] in, For time The proportion of new energy power output at that time For time The impact of renewable energy output on the decay of the equivalent inertia of the power system is used to measure the rate at which the equivalent inertia of the power system decreases when renewable energy output increases.

[0059] Preferably, in this embodiment, the time is calculated using the following formula. New energy power output ratio :

[0060] ,

[0061] in, For time New energy sources (such as wind power and photovoltaics) are contributing their power. For time The output of the synchronous generator.

[0062] Preferably, in this embodiment, time is obtained in the following manner. The impact of new energy output on the equivalent inertia decay of the power system :

[0063] First, estimate the time from the measurement / simulation. Equivalent inertia constant of power system And through calculation The formula for reversing time The impact of new energy output on the equivalent inertia decay of the power system The value of .

[0064] Estimating time from measurement / simulation Equivalent inertia constant of power system This embodiment proposes the following approach:

[0065] Locate the time of disturbance in the measurement data. Take a short time window after the disturbance ,typical For a timeframe of 0.2–2 seconds, bandpass / lowpass filters are applied to the frequency signal to remove high-frequency noise, and the instantaneous time is estimated within the window. (The ROCOF sequence can be obtained using central difference or small window linear fitting). Take a few frames in the initial stage after the perturbation (e.g., the first 0.1–0.5 s), based on inertia and power... The approximate relationship can be used to calculate inversely. .

[0066] Specifically, time Time-frequency oscillation cumulative value include:

[0067] ,

[0068] in, The time window for collecting historical operational data. For time Historical frequencies of the power system It represents the absolute value of the peak acceleration at historical frequencies of the power system.

[0069] Step 102: Construct a frequency offset extreme value discrimination function, calculate the frequency offset extreme value at the current frequency, and determine whether the current equivalent inertia of the current system is insufficient based on the frequency offset extreme value;

[0070] Specifically, the extreme values ​​of frequency offset when calculating the current frequency include:

[0071] ,

[0072] in, For time Time frequency offset extreme value, The rated power of the power system. This is the rated inertia of the power system.

[0073] Specifically, determining whether the current system's current equivalent inertia is insufficiently supported based on the frequency offset extreme value includes: when time Time-frequency offset extreme value When the offset exceeds a preset threshold, the current equivalent inertia of the current system is insufficient to support it.

[0074] Step 103: If the current equivalent inertia of the current system is insufficient, the compensation power of the power system is obtained according to the current frequency of the power system, and power compensation is performed on the power system.

[0075] Preferably, in this embodiment, the compensation power of the power system is obtained using the following formula:

[0076] ,

[0077] in, For time The compensation power of the power system at that time As the reference power of the power system, This is the total equivalent inertia required.

[0078] Specifically, after power compensation is performed on the power system, steps 101 to 103 are executed iteratively until the difference between the total power generation and the total load power in the power system is less than a preset difference threshold.

[0079] Example 2

[0080] like Figure 2 As shown, this embodiment proposes an electromagnetic transient simulation system for the inertia decay effect of a power system, including:

[0081] The frequency acquisition module is used to construct a power system including new energy units and conventional units in the electromagnetic transient simulation platform, acquire the historical operating data of the power system, construct the inertia dynamic equation and embed it into the electromagnetic transient simulation platform, and obtain the current frequency of the power system by solving the inertia dynamic equation.

[0082] Specifically, the historical operating data includes: the rated frequency of the power system, the initial equivalent inertia constant of the power system, the acquisition time window of the historical operating data, the absolute value of the peak acceleration of the power system at the historical frequency, the rated inertia of the power system, and the historical frequency of the power system.

[0083] Specifically, the inertia dynamic equation includes:

[0084] ,

[0085] in, For time Equivalent inertia constant of the power system at that time For time The frequency of the power system The damping coefficient is... For time The difference between the total power generated and the total power of the load in a power system.

[0086] Preferred, for example, damping coefficient It can be .

[0087] Specifically, calculation time Equivalent inertia constant of power system include:

[0088] ,

[0089] in, Let be the initial equivalent inertia constant of the power system. For time The cumulative inertia dissipation factor reflects the degree to which the proportion of new energy sources weakens the equivalent inertia of the power system. For time The cumulative value of frequency oscillations reflects the degree to which frequency fluctuations suppress the effectiveness of the equivalent inertia of the power system.

[0090] Specifically, time Cumulative inertia dissipation factor include: ,

[0091] in, For time The proportion of new energy power output at that time For time The impact of renewable energy output on the decay of the equivalent inertia of the power system is used to measure the rate at which the equivalent inertia of the power system decreases when renewable energy output increases.

[0092] Preferably, in this embodiment, the time is calculated using the following formula. New energy power output ratio :

[0093] ,

[0094] in, For time New energy sources (such as wind power and photovoltaics) are contributing their power. For time The output of the synchronous generator.

[0095] Preferably, in this embodiment, time is obtained in the following manner. The impact of new energy output on the equivalent inertia decay of the power system :

[0096] First, estimate the time from the measurement / simulation. Equivalent inertia constant of power system And through calculation The formula for reversing time The impact of new energy output on the equivalent inertia decay of the power system The value of .

[0097] Estimating time from measurement / simulation Equivalent inertia constant of power system This embodiment proposes the following approach:

[0098] Locate the time of disturbance in the measurement data. Take a short time window after the disturbance ,typical For a timeframe of 0.2–2 seconds, bandpass / lowpass filters are applied to the frequency signal to remove high-frequency noise, and the instantaneous time is estimated within the window. (The ROCOF sequence can be obtained using central difference or small window linear fitting). Take a few frames in the initial stage after the perturbation (e.g., the first 0.1–0.5 s), based on inertia and power... The approximate relationship can be used to calculate inversely. .

[0099] Specifically, time Time-frequency oscillation cumulative value include:

[0100] ,

[0101] in, The time window for collecting historical operational data. For time Historical frequencies of the power system It represents the absolute value of the peak acceleration at historical frequencies of the power system.

[0102] The frequency offset extreme value calculation module is used to construct a frequency offset extreme value discrimination function, calculate the frequency offset extreme value at the current frequency, and determine whether the current equivalent inertia of the current system is insufficient based on the frequency offset extreme value.

[0103] Specifically, the extreme values ​​of frequency offset when calculating the current frequency include:

[0104] ,

[0105] in, For time Time frequency offset extreme value, The rated power of the power system. This is the rated inertia of the power system.

[0106] Specifically, determining whether the current system's current equivalent inertia is insufficiently supported based on the frequency offset extreme value includes: when time Time-frequency offset extreme value When the offset exceeds a preset threshold, the current equivalent inertia of the current system is insufficient to support it.

[0107] The compensation module is used to obtain the compensation power of the power system based on the current frequency of the power system and perform power compensation on the power system if the current equivalent inertia of the current system is insufficient.

[0108] Preferably, in this embodiment, the compensation power of the power system is obtained using the following formula:

[0109] ,

[0110] in, For time The compensation power of the power system at that time As the reference power of the power system, This is the total equivalent inertia required.

[0111] Specifically, after power compensation is performed on the power system, steps 101 to 103 are executed iteratively until the difference between the total power generation and the total load power in the power system is less than a preset difference threshold.

[0112] Example 3

[0113] This invention also proposes a storage medium storing multiple instructions, which are used to implement the aforementioned method for analyzing the multi-dimensional mechanism of power system supply and demand imbalance under new energy grid connection.

[0114] Optionally, in this embodiment, the storage medium may be located in any computer terminal in a group of computer terminals in a computer network, or in any mobile terminal in a group of mobile terminals.

[0115] Optionally, in this embodiment, the storage medium is configured to store program code for performing the following method steps: an electromagnetic transient simulation method for the inertia decay effect of a power system, comprising:

[0116] Step 101: Construct a power system including new energy units and conventional units in the electromagnetic transient simulation platform, obtain historical operating data of the power system, construct an inertia dynamic equation and embed it into the electromagnetic transient simulation platform, and obtain the current frequency of the power system by solving the inertia dynamic equation.

[0117] Specifically, the historical operating data includes: the rated frequency of the power system, the initial equivalent inertia constant of the power system, the acquisition time window of the historical operating data, the absolute value of the peak acceleration of the power system at the historical frequency, the rated inertia of the power system, and the historical frequency of the power system.

[0118] Specifically, the inertia dynamic equation includes:

[0119] ,

[0120] in, For time Equivalent inertia constant of the power system at that time For time The frequency of the power system The damping coefficient is... For time The difference between the total power generated and the total power of the load in a power system.

[0121] Preferred, for example, damping coefficient It can be .

[0122] Specifically, calculation time Equivalent inertia constant of power system include:

[0123] ,

[0124] in, Let be the initial equivalent inertia constant of the power system. For time The cumulative inertia dissipation factor reflects the degree to which the proportion of new energy sources weakens the equivalent inertia of the power system. For time The cumulative value of frequency oscillations reflects the degree to which frequency fluctuations suppress the effectiveness of the equivalent inertia of the power system.

[0125] Specifically, time Cumulative inertia dissipation factor include: ,

[0126] in, For time The proportion of new energy power output at that time For time The impact of renewable energy output on the decay of the equivalent inertia of the power system is used to measure the rate at which the equivalent inertia of the power system decreases when renewable energy output increases.

[0127] Preferably, in this embodiment, the time is calculated using the following formula. New energy power output ratio :

[0128] ,

[0129] in, For time New energy sources (such as wind power and photovoltaics) are contributing their power. For time The output of the synchronous generator.

[0130] Preferably, in this embodiment, time is obtained in the following manner. The impact of new energy output on the equivalent inertia decay of the power system :

[0131] First, estimate the time from the measurement / simulation. Equivalent inertia constant of power system And through calculation The formula for reversing time The impact of new energy output on the equivalent inertia decay of the power system The value of .

[0132] Estimating time from measurement / simulation Equivalent inertia constant of power system This embodiment proposes the following approach:

[0133] Locate the time of disturbance in the measurement data. Take a short time window after the disturbance ,typical For a timeframe of 0.2–2 seconds, bandpass / lowpass filters are applied to the frequency signal to remove high-frequency noise, and the instantaneous time is estimated within the window. (The ROCOF sequence can be obtained using central difference or small window linear fitting). Take a few frames in the initial stage after the perturbation (e.g., the first 0.1–0.5 s), based on inertia and power... The approximate relationship can be used to calculate inversely. .

[0134] Specifically, time Time-frequency oscillation cumulative value include:

[0135] ,

[0136] in, The time window for collecting historical operational data. For time Historical frequencies of the power system It represents the absolute value of the peak acceleration at historical frequencies of the power system.

[0137] Step 102: Construct a frequency offset extreme value discrimination function, calculate the frequency offset extreme value at the current frequency, and determine whether the current equivalent inertia of the current system is insufficient based on the frequency offset extreme value;

[0138] Specifically, the extreme values ​​of frequency offset when calculating the current frequency include:

[0139] ,

[0140] in, For time Time frequency offset extreme value, The rated power of the power system. This is the rated inertia of the power system.

[0141] Specifically, determining whether the current system's current equivalent inertia is insufficiently supported based on the frequency offset extreme value includes: when time Time-frequency offset extreme value When the offset exceeds a preset threshold, the current equivalent inertia of the current system is insufficient to support it.

[0142] Step 103: If the current equivalent inertia of the current system is insufficient, the compensation power of the power system is obtained according to the current frequency of the power system, and power compensation is performed on the power system.

[0143] Preferably, in this embodiment, the compensation power of the power system is obtained using the following formula:

[0144] ,

[0145] in, For time The compensation power of the power system at that time As the reference power of the power system, This is the total equivalent inertia required.

[0146] Specifically, after power compensation is performed on the power system, steps 101 to 103 are executed iteratively until the difference between the total power generation and the total load power in the power system is less than a preset difference threshold.

[0147] Example 4

[0148] This invention also proposes an electronic device, including a processor and a storage medium connected to the processor. The storage medium stores multiple instructions, which can be loaded and executed by the processor to enable the processor to execute the aforementioned method for analyzing the multi-dimensional mechanism of power system supply and demand imbalance under new energy grid connection.

[0149] Specifically, the electronic device in this embodiment can be a computer terminal, which may include one or more processors and a storage medium.

[0150] The storage medium can be used to store software programs and modules, such as the multi-dimensional mechanism analysis method for power system supply and demand imbalance under new energy grid connection in this embodiment of the invention. The corresponding program instructions / modules allow the processor to execute various functional applications and data processing by running the software programs and modules stored in the storage medium, thus realizing the aforementioned multi-dimensional mechanism analysis method for power system supply and demand imbalance under new energy grid connection. The storage medium may include high-speed random access storage media, and may also include non-volatile storage media, such as one or more magnetic storage systems, flash memory, or other non-volatile solid-state storage media. In some instances, the storage medium may further include storage media remotely configured relative to the processor, which can be connected to the terminal via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0151] The processor can call information and application programs stored in the storage medium through the transmission system to execute the following method steps: an electromagnetic transient simulation method for the inertia decay effect of a power system, comprising:

[0152] Step 101: Construct a power system including new energy units and conventional units in the electromagnetic transient simulation platform, obtain historical operating data of the power system, construct an inertia dynamic equation and embed it into the electromagnetic transient simulation platform, and obtain the current frequency of the power system by solving the inertia dynamic equation.

[0153] Specifically, the historical operating data includes: the rated frequency of the power system, the initial equivalent inertia constant of the power system, the acquisition time window of the historical operating data, the absolute value of the peak acceleration of the power system at the historical frequency, the rated inertia of the power system, and the historical frequency of the power system.

[0154] Specifically, the inertia dynamic equation includes:

[0155] ,

[0156] in, For time Equivalent inertia constant of the power system at that time For time The frequency of the power system The damping coefficient is... For time The difference between the total power generated and the total power of the load in a power system.

[0157] Preferred, for example, damping coefficient It can be .

[0158] Specifically, calculation time Equivalent inertia constant of power system include:

[0159] ,

[0160] in, Let be the initial equivalent inertia constant of the power system. For time The cumulative inertia dissipation factor reflects the degree to which the proportion of new energy sources weakens the equivalent inertia of the power system. For time The cumulative value of frequency oscillations reflects the degree to which frequency fluctuations suppress the effectiveness of the equivalent inertia of the power system.

[0161] Specifically, time Cumulative inertia dissipation factor include: ,

[0162] in, For time The proportion of new energy power output at that time For time The impact of renewable energy output on the decay of the equivalent inertia of the power system is used to measure the rate at which the equivalent inertia of the power system decreases when renewable energy output increases.

[0163] Preferably, in this embodiment, the time is calculated using the following formula. New energy power output ratio :

[0164] ,

[0165] in, For time New energy sources (such as wind power and photovoltaics) are contributing their power. For time The output of the synchronous generator.

[0166] Preferably, in this embodiment, time is obtained in the following manner. The impact of new energy output on the equivalent inertia decay of the power system :

[0167] First, estimate the time from the measurement / simulation. Equivalent inertia constant of power system And through calculation The formula for reversing time The impact of new energy output on the equivalent inertia decay of the power system The value of .

[0168] Estimating time from measurement / simulation Equivalent inertia constant of power system This embodiment proposes the following approach:

[0169] Locate the time of disturbance in the measurement data. Take a short time window after the disturbance ,typical For a timeframe of 0.2–2 seconds, bandpass / lowpass filters are applied to the frequency signal to remove high-frequency noise, and the instantaneous time is estimated within the window. (The ROCOF sequence can be obtained using central difference or small window linear fitting). Take a few frames in the initial stage after the perturbation (e.g., the first 0.1–0.5 s), based on inertia and power... The approximate relationship can be used to calculate inversely. .

[0170] Specifically, time Time-frequency oscillation cumulative value include:

[0171] ,

[0172] in, The time window for collecting historical operational data. For time Historical frequencies of the power system It represents the absolute value of the peak acceleration at historical frequencies of the power system.

[0173] Step 102: Construct a frequency offset extreme value discrimination function, calculate the frequency offset extreme value at the current frequency, and determine whether the current equivalent inertia of the current system is insufficient based on the frequency offset extreme value;

[0174] Specifically, the extreme values ​​of frequency offset when calculating the current frequency include

[0175] ,

[0176] in, For time Time frequency offset extreme value, The rated power of the power system. This is the rated inertia of the power system.

[0177] Specifically, determining whether the current system's current equivalent inertia is insufficiently supported based on the frequency offset extreme value includes: when time Time-frequency offset extreme value When the offset exceeds a preset threshold, the current equivalent inertia of the current system is insufficient to support it.

[0178] Step 103: If the current equivalent inertia of the current system is insufficient, the compensation power of the power system is obtained according to the current frequency of the power system, and power compensation is performed on the power system.

[0179] Preferably, in this embodiment, the compensation power of the power system is obtained using the following formula:

[0180] ,

[0181] in, For time The compensation power of the power system at that time As the reference power of the power system, This is the total equivalent inertia required.

[0182] Specifically, after power compensation is performed on the power system, steps 101 to 103 are executed iteratively until the difference between the total power generation and the total load power in the power system is less than a preset difference threshold.

[0183] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0184] In the above embodiments of the present invention, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0185] In the several embodiments provided by this invention, it should be understood that the disclosed technical content can be implemented in other ways. The system embodiments described above are merely illustrative; for example, 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 coupling or direct coupling or communication connection shown or discussed may be through some interfaces, indirect coupling or communication connection between units or modules, and may be electrical or other forms.

[0186] 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.

[0187] 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.

[0188] 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 to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes: USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, optical disks, and other media capable of storing program code.

[0189] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. An electromagnetic transient simulation method for the inertia decay effect of a power system, characterized in that, include: Step 101: Construct a power system including new energy units and conventional units in the electromagnetic transient simulation platform, obtain historical operating data of the power system, construct an inertia dynamic equation and embed it into the electromagnetic transient simulation platform, and obtain the current frequency of the power system by solving the inertia dynamic equation. The historical operating data includes: the rated frequency of the power system, the initial equivalent inertia constant of the power system, the acquisition time window of the historical operating data, the absolute value of the peak acceleration of the power system at the historical frequency, the rated inertia of the power system, and the historical frequency of the power system. The dynamic equations for inertia include: ， in, For time Equivalent inertia constant of the power system at that time For time The frequency of the power system The damping coefficient is... For time The difference between the total generated power and the total load power in the power system at that time; Calculation time Equivalent inertia constant of power system include: ， in, Let be the initial equivalent inertia constant of the power system. For time The cumulative inertia dissipation factor reflects the degree to which the proportion of new energy sources weakens the equivalent inertia of the power system. For time The cumulative value of frequency oscillations reflects the degree to which frequency fluctuations effectively suppress the equivalent inertia of the power system. time Cumulative inertia dissipation factor include: ， in, For time The proportion of new energy power output at that time For time The impact of renewable energy output on the decay of the equivalent inertia of the power system is used to measure the rate at which the equivalent inertia of the power system decreases when renewable energy output increases. time Time-frequency oscillation cumulative value include: ， in, The time window for collecting historical operational data. For time Historical frequencies of the power system This represents the absolute value of the peak acceleration at historical frequencies of the power system. Step 102: Construct a frequency offset extreme value discrimination function, calculate the frequency offset extreme value at the current frequency, and determine whether the current equivalent inertia of the power system is insufficient based on the frequency offset extreme value; Step 103: If the current equivalent inertia of the power system is insufficient, then the compensation power of the power system is obtained according to the current frequency of the power system, and power compensation is performed on the power system.

2. The electromagnetic transient simulation method for the inertia decay effect of a power system as described in claim 1, characterized in that, The extreme values ​​of frequency offset when calculating the current frequency include: ， in, For time Time frequency offset extreme value, The rated power of the power system. This is the rated inertia of the power system.

3. The electromagnetic transient simulation method for the inertia decay effect of a power system as described in claim 2, characterized in that, Determining whether the current equivalent inertia of the power system is insufficient based on the extreme value of the frequency offset includes: when time Time-frequency offset extreme value When the offset exceeds a preset threshold, the current equivalent inertia of the power system is insufficient to support it.

4. The electromagnetic transient simulation method for the inertia decay effect of a power system as described in claim 1, characterized in that, After power compensation is performed on the power system, steps 101 to 103 are executed iteratively until the difference between the total power generation and the total load power in the power system is less than a preset difference threshold.

5. An electromagnetic transient simulation system for the inertia decay effect of a power system, characterized in that, include: The frequency acquisition module is used to construct a power system including new energy units and conventional units in the electromagnetic transient simulation platform, acquire the historical operating data of the power system, construct the inertia dynamic equation and embed it into the electromagnetic transient simulation platform, and obtain the current frequency of the power system by solving the inertia dynamic equation. The historical operating data includes: the rated frequency of the power system, the initial equivalent inertia constant of the power system, the acquisition time window of the historical operating data, the absolute value of the peak acceleration of the power system at the historical frequency, the rated inertia of the power system, and the historical frequency of the power system. The dynamic equations for inertia include: ， in, For time Equivalent inertia constant of the power system at that time For time The frequency of the power system The damping coefficient is... For time The difference between the total generated power and the total load power in the power system at that time; Calculation time Equivalent inertia constant of power system include: ， in, Let be the initial equivalent inertia constant of the power system. For time The cumulative inertia dissipation factor reflects the degree to which the proportion of new energy sources weakens the equivalent inertia of the power system. For time The cumulative value of frequency oscillations reflects the degree to which frequency fluctuations effectively suppress the equivalent inertia of the power system. time Cumulative inertia dissipation factor include: ， in, For time The proportion of new energy power output at that time For time The impact of renewable energy output on the decay of the equivalent inertia of the power system is used to measure the rate at which the equivalent inertia of the power system decreases when renewable energy output increases. time Time-frequency oscillation cumulative value include: ， in, The time window for collecting historical operational data. For time Historical frequencies of the power system This represents the absolute value of the peak acceleration at historical frequencies of the power system. The frequency offset extreme value calculation module is used to construct a frequency offset extreme value discrimination function, calculate the frequency offset extreme value at the current frequency, and determine whether the current equivalent inertia of the power system is insufficient based on the frequency offset extreme value. The compensation module is used to obtain the compensation power of the power system based on the current frequency of the power system if the current equivalent inertia of the power system is insufficient, and to perform power compensation on the power system.

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