Asynchronous interconnected dual-region frequency coordinated control method and device

Abstract

The present invention discloses a method and apparatus for coordinated frequency control of asynchronously interconnected dual-areas. The method comprises: obtaining information about asynchronously interconnected dual-areas; constructing an asynchronously interconnected dual-area model based on the information; calculating control parameters based on the asynchronously interconnected dual-area model, wherein the control parameters include a proportional coefficient and an integral coefficient; determining a target control mode combination based on a control mode of automatic power generation control, wherein the control mode includes constant frequency control, constant power control, and tie-line deviation control; and performing coordinated frequency control of the dual-areas based on the control parameters and the target control mode combination. The present invention implements coordinated frequency control and improves accuracy and frequency stability. The present invention can be widely applied in the field of power engineering technology.

Description

Technical Field

[0001] The present invention relates to the field of electric power engineering technology, and in particular to an asynchronous interconnected dual-area frequency coordinated control method and device. Background Art

[0002] High-voltage direct current (HVDC) transmission technology boasts low construction costs, minimal transmission losses, and minimal environmental impact. However, the isolation characteristics of DC transmission somewhat weaken the ability of power grids to provide mutual support. In an asynchronous power grid system connected only by an HVDC link, the frequencies of the two grids are independent of each other, requiring DC power transmission to rapidly respond to grid frequency changes and improve grid frequency stability. Traditional frequency control methods only control the frequency of the power system at the sending or receiving end of the DC system, and design and optimize the frequency controller and parameters of the sending-end grid. However, the overall frequency dynamics of both the sending and receiving ends of the power system result in low control accuracy and frequency stability.

[0003] In summary, the technical problems existing in the relevant technologies need to be improved. Summary of the Invention

[0004] The embodiments of the present invention provide a method and device for asynchronously interconnected dual-region frequency coordinated control, which effectively improves accuracy and frequency stability.

[0005] On the one hand, an embodiment of the present invention provides an asynchronous interconnected dual-region frequency coordinated control method, comprising the following steps:

[0006] Get asynchronous interconnected dual-region information;

[0007] Constructing an asynchronous interconnected dual-region model according to the asynchronous interconnected dual-region information;

[0008] Calculating control parameters according to the asynchronous interconnected dual-region model, wherein the control parameters include a proportional coefficient and an integral coefficient;

[0009] determining a target control mode combination according to a control mode of automatic power generation control, wherein the control mode includes constant frequency control, constant power control, and tie line deviation control;

[0010] Dual-region frequency coordinated control is performed according to the combination of the control parameters and the target control mode.

[0011] In some embodiments, constructing an asynchronous interconnected dual-region model according to the asynchronous interconnected dual-region information includes:

[0012] Construct a steam turbine prime mover model based on the steam volume time constant;

[0013] According to the time constant of water hammer effect, the turbine prime mover model is constructed;

[0014] Constructing a DC frequency controller model according to the proportional coefficient and the integral coefficient;

[0015] The asynchronous interconnected dual-region model is constructed according to the steam turbine prime mover model, the water turbine prime mover model, the DC frequency controller model, the asynchronous interconnected dual-region information, the hydropower unit regulation coefficient and the thermal power unit regulation coefficient.

[0016] In some embodiments, calculating the control parameter according to the asynchronous interconnected dual-region model includes:

[0017] Performing equivalent transformation on the asynchronous interconnected dual-region model to obtain a dual-region structure block diagram of the asynchronous interconnected system;

[0018] Constructing a closed-loop system transfer function based on the dual-region structure block diagram of the asynchronous interconnected system and the power disturbance;

[0019] constructing a denominator polynomial according to the closed-loop system transfer function;

[0020] Constructing a system characteristic equation according to the denominator polynomial;

[0021] Calculating closed-loop poles according to the system characteristic equation;

[0022] According to the Routh criterion and the denominator polynomial, a Routh table is constructed;

[0023] Constructing necessary and sufficient condition constraints for system stability based on the Routh table and the closed-loop poles;

[0024] Calculate the relationship between system stability and control parameters based on the necessary and sufficient conditions for system stability;

[0025] Determining a control parameter stability region based on the relationship between the system stability and the control parameter;

[0026] Calculate the comprehensive stabilization time based on the step stabilization time;

[0027] The control parameter is determined according to the asynchronous interconnection system parameter, the control parameter stability domain and the comprehensive stability time.

[0028] In some embodiments, determining the target control mode combination according to the control mode of the automatic power generation control includes:

[0029] Calculating the regional control deviation of the fixed frequency control according to the frequency deviation and the regional frequency deviation coefficient;

[0030] Calculating a regional control deviation of the tie-line deviation control according to the frequency deviation, the regional frequency deviation coefficient, and the interconnected system tie-line power;

[0031] Determining a control mode combination to be selected according to the control mode;

[0032] Calculating, based on the proportional coefficient and the integral coefficient, a relationship between a frequency change of the asynchronous interconnected dual-region power grid and the combination of the control modes to be selected;

[0033] Calculating, based on the proportional coefficient and the integral coefficient, a relationship between the DC transmission power involved in frequency regulation and the combination of the control modes to be selected;

[0034] Based on the regional control deviation of the fixed frequency control, the regional control deviation of the tie-line deviation control, the relationship between the frequency change of the asynchronous interconnected dual-region power grid and the candidate control mode combination, and the relationship between the DC transmission power participating in frequency regulation and the candidate control mode combination, an adaptive analysis of automatic power generation control is performed to obtain the target control mode combination.

[0035] In some embodiments, the method further comprises:

[0036] Conduct dual-region frequency coordinated control experiments;

[0037] The dual-region frequency coordinated control experiment comprises the following steps:

[0038] In the asynchronous interconnected dual-region model, setting the grid capacity of the first region and the grid capacity of the second region;

[0039] The power disturbance in the first area, the power disturbance in the second area and the DC blocking fault are simulated and analyzed, and the frequency control experimental results are obtained.

[0040] In some embodiments, the closed-loop system transfer function is expressed as:

[0041] ,

[0042] Where, is the closed-loop system transfer function with the power disturbance in the first region as input, is the Laplace transform of the frequency difference between the two regions, is the Laplace transform of the power disturbance in the first region, and are polynomial coefficients, , , is the complex variable in the Laplace transform, .

[0043] In some embodiments, calculating the comprehensive stabilization time according to the step stabilization time includes:

[0044] According to the step stabilization time, the comprehensive stabilization time is calculated by the comprehensive stabilization time calculation formula, which is:

[0045] ,

[0046] Where, is the comprehensive stabilization time, is the step settling time after the step disturbance occurs in the first region, is the step settling time after a step disturbance occurs in the second region.

[0047] In some embodiments, calculating the regional control deviation of the tie-line deviation control based on the frequency deviation, the regional frequency deviation coefficient, and the interconnected system tie-line power includes:

[0048] According to the frequency deviation, the regional frequency deviation coefficient and the interconnected system tie line power, the regional control deviation of the tie line deviation control is calculated by the regional control deviation calculation formula of the tie line deviation control. The regional control deviation calculation formula of the tie line deviation control is:

[0049] ,

[0050] Where, is the regional control deviation of the tie line deviation control, is the regional frequency deviation coefficient, is the frequency deviation, is the tie line power of the interconnected system.

[0051] On the other hand, an embodiment of the present invention provides an asynchronous interconnected dual-region frequency coordinated control device, including:

[0052] The first module is used to obtain asynchronous interconnected dual-region information;

[0053] The second module is used to build an asynchronous interconnected dual-region model according to the asynchronous interconnected dual-region information;

[0054] A third module is configured to calculate control parameters according to the asynchronous interconnected dual-region model, wherein the control parameters include a proportional coefficient and an integral coefficient;

[0055] A fourth module is configured to determine a target control mode combination according to a control mode of automatic power generation control, wherein the control mode includes constant frequency control, constant power control, and tie line deviation control;

[0056] The fifth module is used to perform dual-area frequency coordinated control according to the combination of the control parameters and the target control mode.

[0057] In another aspect, an embodiment of the present invention provides a computer device, comprising:

[0058] at least one processor;

[0059] at least one memory for storing at least one program;

[0060] When the at least one program is executed by the at least one processor, the at least one processor implements the method.

[0061] The beneficial effects of the present invention are as follows:

[0062] The embodiment of the present invention first obtains asynchronous interconnected dual-area information, then constructs an asynchronous interconnected dual-area model based on the asynchronous interconnected dual-area information, calculates control parameters based on the asynchronous interconnected dual-area model, and then determines a target control mode combination based on the control mode of automatic power generation control. Finally, dual-area frequency collaborative control is performed based on the control parameters and the target control mode combination, so that frequency collaborative control can be achieved by determining the optimal control parameters and control mode, thereby improving accuracy and frequency stability.

[0063] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained through the structures particularly pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0065] Figure 1 This is a flow chart of an asynchronous interconnected dual-region frequency coordinated control method according to an embodiment of the present invention;

[0066] Figure 2 This is a schematic diagram of a back-to-back DC engineering structure at site A according to an embodiment of the present invention;

[0067] Figure 3 A schematic diagram of a steam turbine prime mover model structure according to an embodiment of the present invention;

[0068] Figure 4This is a schematic diagram of a hydraulic turbine prime mover model structure according to an embodiment of the present invention;

[0069] Figure 5 A schematic diagram of a DC frequency controller model structure according to an embodiment of the present invention;

[0070] Figure 6 A schematic diagram of an asynchronous interconnected dual-region model structure according to an embodiment of the present invention;

[0071] Figure 7 This is a block diagram of a dual-zone structure of an asynchronous interconnection system according to an embodiment of the present invention;

[0072] Figure 8 A schematic diagram of parameters of an asynchronous interconnected dual-region model according to an embodiment of the present invention;

[0073] Figure 9 A schematic diagram of a control parameter value range when the system is stable according to an embodiment of the present invention;

[0074] Figure 10 This is a comparison diagram of the frequency deviations of regions 1 and 2 under DC frequency control, and the frequency deviation of region 1 without control, according to an embodiment of the present invention;

[0075] Figure 11 This is an embodiment of the present invention When the value is appropriate, different Comparison chart of the impact on frequency deviation in region 1;

[0076] Figure 12 This is an embodiment of the present invention When the value is appropriate, different Comparison chart of the impact on frequency deviation in region 1;

[0077] Figure 13 A control parameter of the embodiment of the present invention is 、 Comprehensive stabilization time Impact comparison chart;

[0078] Figure 14 This is a schematic diagram of a DC frequency control effect after considering secondary frequency modulation according to an embodiment of the present invention;

[0079] Figure 15 A frequency deviation comparison diagram of region 1 under different control modes according to an embodiment of the present invention;

[0080] Figure 16 This is a comparison diagram of DC frequency modulation power under different control modes according to an embodiment of the present invention;

[0081] Figure 17This is a comparison diagram of frequency deviations of two regions under disturbance in the first region without AGC according to an embodiment of the present invention;

[0082] Figure 18 This is a comparison diagram of frequency deviations of the two side areas under the second area disturbance without AGC in an embodiment of the present invention;

[0083] Figure 19 This is a comparison diagram of frequency deviations in the two side regions under DC blocking without AGC in an embodiment of the present invention;

[0084] Figure 20 This is a schematic diagram of the difference in frequency between two regions under disturbance in the first region without AGC according to an embodiment of the present invention;

[0085] Figure 21 This is a schematic diagram of the difference in frequency between the two side areas under the second area disturbance without AGC according to an embodiment of the present invention;

[0086] Figure 22 A schematic diagram of the difference in frequency between two regions under DC blocking without AGC according to an embodiment of the present invention;

[0087] Figure 23 This is a schematic diagram of DC frequency modulation power under first region disturbance without AGC according to an embodiment of the present invention;

[0088] Figure 24 This is a schematic diagram of DC frequency modulation power under second-region disturbance without AGC according to an embodiment of the present invention;

[0089] Figure 25 This is a schematic diagram of DC frequency modulation power under DC blocking without AGC according to an embodiment of the present invention;

[0090] Figure 26 This is a comparison diagram of frequency deviations of two regions under disturbance in the first region when AGC is enabled in an embodiment of the present invention;

[0091] Figure 27 This is a comparison diagram of frequency deviations of two regions under disturbance in the second region when AGC is enabled in an embodiment of the present invention;

[0092] Figure 28 This is a comparison diagram of frequency deviations in two regions under DC blocking with AGC in an embodiment of the present invention;

[0093] Figure 29 This is a schematic diagram of the difference in frequency between two regions under disturbance in the first region when AGC is enabled according to an embodiment of the present invention;

[0094] Figure 30 This is a schematic diagram of the difference in frequency between the two side regions under the disturbance of the second region when AGC is enabled according to an embodiment of the present invention;

[0095] Figure 31 A schematic diagram of the difference in frequency between two regions under DC blocking with AGC in an embodiment of the present invention;

[0096] Figure 32 This is a schematic diagram of DC frequency modulation power under first-region disturbance with AGC in an embodiment of the present invention;

[0097] Figure 33 This is a schematic diagram of DC frequency modulation power under second-region disturbance with AGC in an embodiment of the present invention;

[0098] Figure 34 This is a schematic diagram of DC frequency modulation power under DC blocking with AGC according to an embodiment of the present invention;

[0099] Figure 35 This is a schematic structural diagram of an asynchronous interconnected dual-region frequency coordinated control device according to an embodiment of the present invention;

[0100] Figure 36 The figure is a schematic diagram of the hardware structure of a computer device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0101] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application is further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the present application and are not intended to limit the present application. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the embodiments of the present application. They are merely examples of devices and methods consistent with some aspects of the embodiments of the present application as detailed in the appended claims.

[0102] It will be understood that the terms "first", "second", etc. used in this application may be used herein to describe various concepts, but unless otherwise specified, these concepts are not limited by these terms. These terms are only used to distinguish one concept from another. For example, without departing from the scope of the embodiments of the present application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the words "if" and "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining".

[0103] The terms "at least one", "plurality", "each", "any", etc. used in this application include "at least one", "two" or more, "plurality" or "each", "any" or "any one", "each" or "any one" as used herein.

[0104] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application pertains. The terms used herein are for the purpose of describing the embodiments of this application only and are not intended to limit this application.

[0105] Before explaining the embodiments of the present application in detail, some of the nouns and terms involved in the embodiments of the present application are first explained. The nouns and terms involved in the embodiments of the present application are subject to the following explanations.

[0106] Asynchronous interconnection: refers to the asynchronous connection between power grids in different regions through power electronic equipment.

[0107] Among related technologies, high-voltage direct current (HVDC) transmission is considered an efficient solution for power system interconnection due to its low construction cost, minimal transmission losses, and minimal environmental impact. Asynchronous grid interconnection, a key application area of HVDC technology, enables asynchronous operation between regional power grids through back-to-back DC projects. However, the isolation characteristics of DC transmission somewhat weaken the ability of power grids to support each other. In an asynchronous grid system connected only by an HVDC link, the frequencies of the two grids are independent of each other, posing new challenges for grid frequency stability and power support. Therefore, in the context of asynchronous interconnection, optimizing scheduling strategies and rationally allocating and coordinating frequency regulation resources within the grid to maintain grid frequency stability and ensure system reliability and security have become urgent challenges in power system research. DC power transmission can rapidly respond to grid frequency changes, provide necessary power support, and improve grid frequency stability. Currently, research on DC frequency regulation primarily focuses on its application in sending or receiving grids. Most frequency control analyses focus solely on frequency control strategies for power systems on either the sending or receiving side of a DC system, failing to consider frequency variations on both sides of the interconnected DC system and the impact of control schemes on the frequency characteristics of both sides. Research on DC frequency control parameter tuning optimization focuses primarily on the design and optimization of frequency controllers for the sending-side grid, but lacks consideration of the overall frequency dynamics of both sides of the interconnected DC system. Furthermore, most studies fail to examine the adaptability of asynchronously interconnected DC power grids after the introduction of Automatic Generation Control (AGC) under co-frequency control, resulting in low control accuracy and frequency stability. Therefore, in the current context, the frequency stability of asynchronously interconnected power systems warrants further attention, and greater research and attention are urgently needed on DC frequency control on both sides of the system. Furthermore, theoretical analysis, key control parameter tuning, and adaptability of coordination with AGC are particularly pressing.

[0108] In view of this, the embodiment of the present invention proposes a method and device for asynchronous interconnected dual-area frequency coordinated control. First, a frequency dynamic analysis model of an asynchronous interconnected dual-area system with AGC in the same frequency control mode is built, including models such as steam turbine prime mover, water turbine prime mover, DC frequency controller, and AGC control. It can not only simulate the frequency response of the system under different working conditions, but also provide a theoretical basis for the optimization of subsequent control strategies. Secondly, a stability analysis is performed on the asynchronous interconnected model to calculate the control parameters. , The stability domain of the grid is proposed, and a parameter optimization method considering the frequency synchronization time of the two sides of the asynchronous interconnection is proposed. The proportional coefficient in the DC frequency controller is , integral coefficient Parameter optimization was performed to enable frequency regulation resource sharing and rapid frequency support between asynchronously interconnected regional power grids. Finally, an adaptability analysis of DC frequency control and AGC control was conducted, studying the frequency deviation variations and DC frequency regulation power variations under different control modes. Frequency coordination was also implemented under the same-frequency control mode, taking into account different AGC control modes.

[0109] An asynchronous interconnected dual-area frequency coordinated control method provided in an embodiment of the present application relates to the field of power engineering technology. An asynchronous interconnected dual-area frequency coordinated control method provided in an embodiment of the present application can be applied to a terminal, can be applied to a server, or can be software running in a terminal or a server. In some embodiments, the terminal can be a smart phone, a tablet computer, a laptop computer, a desktop computer, a smart speaker, a smart watch, and a car terminal, etc., but is not limited thereto; the server side can be configured as an independent physical server, or as a server cluster or distributed system consisting of multiple physical servers, or as a cloud server that provides basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communications, middleware services, domain name services, security services, CDN, and big data and artificial intelligence platforms. The server can also be a node server in a blockchain network; the software can be an application that implements an asynchronous interconnected dual-area frequency coordinated control method, etc., but is not limited to the above forms.

[0110] The present application can be used in many general or special computer system environments or configurations. For example: personal computers, server computers, handheld or portable devices, tablet devices, multiprocessor systems, microprocessor-based systems, set-top boxes, programmable consumer electronics, network PCs, minicomputers, mainframe computers, distributed computing environments including any of the above systems or devices, and the like. The present application can be described in the general context of computer-executable instructions executed by a computer, such as program modules. Generally, program modules include routines, programs, objects, components, data structures, and the like that perform specific tasks or implement specific abstract data types. The present application can also be practiced in distributed computing environments in which tasks are performed by remote processing devices connected via a communication network. In a distributed computing environment, program modules can be located in local and remote computer storage media, including storage devices.

[0111] The following is a detailed explanation of the embodiments of the present application with reference to the accompanying drawings:

[0112] Figure 1 This is an optional flow chart of an asynchronous interconnected dual-region frequency coordinated control method provided in an embodiment of the present application. Figure 1 The method may include but is not limited to steps S101 to S105.

[0113] Step S101, obtaining asynchronous interconnected dual-region information;

[0114] Step S102: constructing an asynchronous interconnected dual-region model based on the asynchronous interconnected dual-region information;

[0115] Step S103: Calculate control parameters according to the asynchronous interconnected dual-region model, where the control parameters include a proportional coefficient and an integral coefficient;

[0116] Step S104: determining a target control mode combination according to the control mode of automatic power generation control, where the control modes include constant frequency control, constant power control, and tie line deviation control;

[0117] Step S105: Perform dual-region frequency coordinated control according to the control parameter and target control mode combination.

[0118] Steps S101 to S105 shown in the embodiment of the present application implement frequency coordinated control and improve accuracy and frequency stability.

[0119] In step S101 of some embodiments, the asynchronous interconnected dual-region information may be obtained through a power system information database, or other methods, without limitation.

[0120] In some embodiments, in step S102, constructing an asynchronous interconnected dual-region model based on the asynchronous interconnected dual-region information may include but is not limited to the following steps:

[0121] Construct a steam turbine prime mover model based on the steam volume time constant;

[0122] According to the time constant of water hammer effect, the turbine prime mover model is constructed;

[0123] Construct a DC frequency controller model based on the proportional coefficient and integral coefficient;

[0124] An asynchronous interconnected dual-area model is constructed based on the steam turbine prime mover model, the water turbine prime mover model, the DC frequency controller model, the asynchronous interconnected dual-area information, the hydropower unit regulation coefficient and the thermal power unit regulation coefficient.

[0125] In some embodiments, asynchronous interconnection refers to the asynchronous connection between power grids in different regions through power electronic equipment. The asynchronous interconnected power grid achieves precise control and rapid adjustment of the transmitted power through the high controllability of the DC transmission system, thereby improving the security and flexibility of the power grid. Figure 2 As shown, the combination of high-capacity flexible DC and conventional DC can improve the grid's flexible power control, reduce transmission losses and transmission failures, and ensure safe and stable grid operation. In the figure, VSC (Voltage Source Converter) represents a voltage source converter, and LCC (Line-Commutated Converter) represents a current source converter. VSC offers greater flexibility and control capabilities, while LCC may be more cost-effective in certain applications. Asynchronous DC interconnection enables AC power systems with different frequencies to exchange power, addressing cross-regional grid stability issues. However, this also compromises inter-regional frequency support. To enhance frequency support between two regions via DC interconnection, this embodiment uses PI control (Proportional Integral Controller) as the DC frequency controller to achieve frequency synchronization control across the asynchronous interconnected regions. Using the frequency deviation between the two regions as input, the PI controller dynamically adjusts the DC system output power to simultaneously regulate frequency stability in both regions. For example, when a power disturbance causes a drop in frequency in one region, the DC frequency controller detects the frequency deviation between the two regions and, through PI control, directs the DC system to output higher power to the lower-frequency region, thereby achieving frequency support for the lower-frequency region from the higher-frequency region.

[0126] The steam turbine prime mover model can be constructed based on the steam volume time constant. The steam turbine prime mover model structure is as follows: Figure 3 As shown, is the steam volume time constant. Then, based on the water hammer effect time constant, the turbine prime mover model is constructed, where the turbine prime mover model structure is as follows: Figure 4 As shown, is the time constant of water hammer effect. Then, according to the proportional coefficient and integral coefficient, a DC frequency controller model is constructed. The DC frequency controller model structure is as follows: Figure 5 As shown, the controller adopts PI control (proportional integral controller), with the frequency difference as input. is the proportionality coefficient, is the integration coefficient, Finally, based on the steam turbine prime mover model, the water turbine prime mover model, the DC frequency controller model, the asynchronous interconnection dual-region information, the hydropower unit regulation coefficient and the thermal power unit regulation coefficient, the asynchronous interconnection dual-region model is constructed. Figure 6 As shown, there are two regions, is the system equivalent inertia in the first region, is the system equivalent inertia in the second region, is the equivalent damping coefficient of the first region, is the equivalent damping coefficient of the second region, is the turbine prime mover model of the hydroelectric unit, is the hydropower unit regulation coefficient, is the proportion of hydropower generation, is the steam turbine prime mover model, is the regulation coefficient of thermal power units, is the proportion of power generation from thermal power units, Transmitting power for DC tie lines, is a DC frequency controller, is the regional frequency deviation coefficient of the first region (MW / 0.1Hz), is the regional frequency deviation coefficient of the second region (MW / 0.1Hz), is the integral coefficient of the AGC in the first area, is the integral coefficient of the AGC in the second area, is the DC output power of the first region, is the DC output power of the second region, is the grid frequency deviation in the first region, is the grid frequency deviation in the second area.

[0127] It is understandable that the DC frequency controller uses the power regulation characteristics of the HVDC (high voltage direct current transmission) system to link the frequencies of the power grids on both sides. When a power disturbance occurs on one side of the power grid, resulting in a frequency deviation, the DC frequency controller generates an adjustment instruction by detecting the frequency difference and adjusts the HVDC transmission power based on the proportional integral control algorithm. By increasing or decreasing the power transmitted from one side of the power grid to the other, the frequency is gradually converged. Since the HVDC system responds quickly, it can suppress frequency deviations and restore grid stability in a short time, thereby achieving frequency support and same-frequency control of asynchronous interconnected power grids. Control parameters of the DC frequency controller 、 The value of not only affects the stability of the DC interconnected system but also the effectiveness of the DC frequency controller in regulating the frequency of the power grids on both sides. Therefore, a theoretical analysis of system stability is required to determine the impact of the DC frequency controller parameter values on the frequency stability of the interconnected system on both sides.

[0128] In some embodiments, in step S103, the control parameters are calculated according to the asynchronous interconnected dual-region model, which may include but is not limited to the following steps:

[0129] Perform equivalent transformation on the asynchronous interconnected dual-area model to obtain the dual-area structure block diagram of the asynchronous interconnected system;

[0130] According to the dual-area structure diagram of the asynchronous interconnected system and the power disturbance, the closed-loop system transfer function is constructed;

[0131] Construct the denominator polynomial according to the closed-loop system transfer function;

[0132] Based on the denominator polynomial, construct the system characteristic equation;

[0133] Calculate the closed-loop poles based on the system characteristic equation;

[0134] According to Routh criterion and denominator polynomial, construct Routh table;

[0135] According to Routh table and closed-loop poles, construct necessary and sufficient condition constraints for system stability;

[0136] Calculate the relationship between system stability and control parameters based on the necessary and sufficient conditions for system stability;

[0137] According to the relationship between system stability and control parameters, the control parameter stability domain is determined;

[0138] Calculate the comprehensive stabilization time based on the step stabilization time;

[0139] The control parameters are determined according to the asynchronous interconnection system parameters, the control parameter stability domain and the comprehensive stability time.

[0140] In some embodiments, control parameters can be calculated based on the asynchronous interconnected dual-region model, where the control parameters include proportional coefficients and integral coefficients. In the process of calculating the control parameters, AGC control (automatic generation control) can be temporarily ignored, and only the relationship between DC frequency control and system primary frequency regulation control can be considered. The asynchronous interconnected dual-region model can be transformed equivalently to obtain a dual-region structure block diagram of the asynchronous interconnected system, where the dual-region structure block diagram of the asynchronous interconnected system is as follows: Figure 7 As shown, The power disturbance in the first region is is the power disturbance of the second region, and the output y is the difference between the frequencies of the two regions. The reference value of the frequency difference is set to zero to make the frequencies of the two regions consistent. Then, according to the dual-region structure block diagram of the asynchronous interconnected system and the power disturbance, the closed-loop system transfer function is constructed. For example, the system structure block diagram is analyzed, and the power disturbances of the first region and the second region are respectively and As input, the frequency deviation between the two regions As output, analyze the power disturbances at different and The closed-loop system transfer function is and , where the expression of the closed-loop system transfer function with the power disturbance in the first region as input is: , the expression of the closed-loop system transfer function when the power disturbance in the second region is used as input is: , where is the closed-loop system transfer function with the power disturbance in the first region as input, is the closed-loop system transfer function with the power disturbance in the second region as input, is the Laplace transform of the frequency difference between the two regions, is the Laplace transform of the power disturbance in the first region, is the Laplace transform of the power disturbance in the second region, 、 and are polynomial coefficients, , , , , is the complex variable in the Laplace transform, It is understood that in control system analysis, the closed-loop transfer function describes the mathematical relationship between the output response and the input signal in a closed-loop control system. Correct analysis of the closed-loop transfer function can ensure that the system is stable and has dynamic and steady-state characteristics that meet the requirements of specific applications.

[0141] Then, based on the closed-loop system transfer function, the denominator polynomial is constructed, where the expression of the denominator polynomial is: , where is the denominator polynomial. Then, based on the denominator polynomial, the system characteristic equation is constructed, and the closed-loop poles are calculated based on the system characteristic equation. For example, the denominator polynomial of the closed-loop system transfer function of the asynchronous interconnected dual-region model is about A fifth-order polynomial is taken and set equal to zero to construct the system's characteristic equation. The characteristic equation plays a crucial role in control system stability analysis because it is directly related to the poles of the closed-loop system. The stability of a closed-loop system is entirely determined by the roots (closed-loop poles) of the closed-loop characteristic equation. Based on the Routh criterion and the denominator polynomial, a Routh table is constructed. The Routh criterion is a mathematical method used to determine system stability. It determines system stability by analyzing the coefficients of the denominator polynomial of the closed-loop transfer function. If all poles of the closed-loop transfer function lie in the left half of the complex plane, the system is stable; if any poles lie in the right half, the system is unstable. Constructing a Routh table avoids solving higher-order characteristic equations and simplifies the stability analysis process. Based on the Routh table and the closed-loop poles, necessary and sufficient constraints for system stability are constructed. It is understandable that according to the Routh criterion analysis, the necessary and sufficient conditions for system stability are: all coefficients of the characteristic equation are positive numbers, and the elements in the first column of the Routh table are all positive numbers; therefore, the necessary and sufficient conditions for the system stability of the asynchronous interconnected system are expressed as: , where , , , .

[0142] Then, according to the necessary and sufficient conditions for system stability, the relationship between system stability and control parameters is calculated, and the stability domain of control parameters is determined based on the relationship between system stability and control parameters. For example, by constructing a Routh table for the denominator polynomial of the closed-loop transfer function of the interconnected system, the controller parameters are calculated and analyzed under the constraints of the necessary and sufficient conditions for system stability, and the system stability and control parameters are obtained. 、 , thus obtaining the system's 、 The control parameter stability domain. The asynchronous interconnected dual-region model parameters can be set as Figure 8 As shown, the parameters are substituted into the asynchronous interconnected dual-region model, the denominator polynomial of the closed-loop transfer function is calculated, and the stability condition of the Routh criterion is combined to obtain the system stability. 、 The range of values of the control parameters of the DC frequency controller under the condition of system stability is obtained as follows: Figure 9The shaded area is shown in the figure. When a power disturbance occurs, the frequency of the grid on one side changes, and the frequency difference between the two grids increases. The DC frequency controller starts to respond and adjusts the DC output power to reduce the frequency difference until the frequencies of the two grids return to the same level. 、 When the value is appropriate, the frequency changes of the two regions under DC frequency control, and the grid frequency changes on the disturbance-occurring side without DC frequency control are as follows: Figure 10 shown. Figure 10 In the case of no DC frequency control, the maximum frequency deviation after the disturbance in the first area is -0.036Hz. When DC frequency control is used, the maximum frequency deviation is -0.018Hz. It can be seen that the control parameters 、 When the value is appropriate, the frequency deviation can be greatly reduced, and the time for the frequency to reach stability will also be greatly shortened, realizing timely and effective frequency support of asynchronous interconnected dual regions. When the DC frequency controller takes the frequency deviation of the two regions as input, the deviation is 0 as the reference value, such as Figure 11 As shown in the figure, the frequency of the first area drops rapidly after the disturbance occurs, and the frequency of the second area follows synchronously under the action of the controller. 、 When the values are appropriate, the frequencies of the two regions can converge within a few seconds. In addition to system stability, the control parameters 、 The value has an important influence on the minimum frequency value and the stabilization time of the two sides. 、 The frequency change of the first area under the parameter is as follows Figure 11 and Figure 12 The frequency change of the second area is not shown in the figure. The frequency synchronization effect is shown in Figure 10 . Figure 11 In, when When choosing an appropriate value, When the frequency deviation is large, the When it is close to the critical value of the stable region, it shows oscillation phenomenon and the stable time is longer. When it increases, the frequency deviation decreases and the stabilization time decreases; when When it is greater than a certain level, The influence of increasing on the frequency stability index decreases, the maximum value of frequency deviation increases slightly in the opposite direction, and the frequency stabilization time remains almost unchanged. Figure 12 In, when When choosing an appropriate value, When it is smaller, the frequency deviation is larger and the stabilization time is longer; when When it increases, the frequency deviation gradually decreases and the stabilization time decreases; when When it is greater than a certain level, The increase in frequency has almost no effect on the frequency stabilization time, but the maximum value of the frequency deviation increases in the opposite direction.

[0143] Finally, based on the step stabilization time, the comprehensive stabilization time is calculated using the comprehensive stabilization time calculation formula, and the control parameters are determined based on the asynchronous interconnection system parameters, the control parameter stability domain, and the comprehensive stabilization time. The comprehensive stabilization time calculation formula is: , where is the comprehensive stabilization time, The closed-loop transfer function when a power step disturbance occurs in the first region is The step settling time, The closed-loop transfer function when a power step disturbance occurs in the second region is It can be understood that the stabilization time is used to describe the ability of the system output to enter and maintain near the final steady-state value after experiencing a step input. A shorter stabilization time indicates that the system can reach a stable state faster. In the above analysis, when 、 When the value is within the appropriate range, the maximum frequency deviation control effect is better and closer, and the stabilization time required for the frequency difference between the two regions to return to the reference value of 0 is usually the frequency stability indicator that is more valued in engineering. The time required for the frequency deviation of the two power grids to return to consistency when a disturbance occurs can be comprehensively considered, that is, the comprehensive stabilization time , where the stability range is 2% of the maximum frequency difference between the two sides after the disturbance occurs, that is, The shorter the stabilization time, the better the frequency control effect of the DC frequency controller. Control parameters of DC frequency controller 、 The relationship as Figure 13 shown. Figure 13 In the figure, only the points with comprehensive stabilization time less than 25s are retained for display. When the control parameters are near the boundary of the stable region, the stabilization time increases significantly and the frequency change shows an oscillatory phenomenon. and Gradually increase the stabilization time and gradually decrease; when When it increases to a certain extent, if Continue to increase, comprehensive stabilization time will decrease at a very slow rate, i.e. continue to increase The income is close to 0; when When it increases to a certain extent, if If the value continues to increase, the comprehensive stabilization time will show a slight increasing trend. In summary, the comprehensive stabilization time should be reduced to within 3 seconds and the control parameters should be 、 Comprehensive stabilization time when the value is minimum The best benefit can be obtained by optimizing and analyzing with Matlab mathematical tools. =1609, =6136 when the DC frequency control effect is optimal.

[0144] In some embodiments, in step S104, determining a target control mode combination according to the control mode of the automatic power generation control may include but is not limited to the following steps:

[0145] Calculate the regional control deviation of fixed frequency control based on the frequency deviation and regional frequency deviation coefficient;

[0146] Calculate the regional control deviation of tie line deviation control based on frequency deviation, regional frequency deviation coefficient and interconnected system tie line power;

[0147] According to the control mode, determine the control mode combination to be selected;

[0148] According to the proportional coefficient and integral coefficient, the relationship between the frequency change of the power grid on both sides of the asynchronous interconnected dual-area and the combination of the selected control modes is calculated;

[0149] Calculate the relationship between the DC transmission power involved in frequency regulation and the combination of the selected control modes based on the proportional coefficient and the integral coefficient;

[0150] Based on the regional control deviation of fixed frequency control, the regional control deviation of tie-line deviation control, the relationship between the frequency change of the power grids on both sides of the asynchronous interconnected dual regions and the candidate control mode combination, and the relationship between the DC transmission power participating in frequency regulation and the candidate control mode combination, an adaptability analysis of automatic power generation control is performed to obtain the target control mode combination.

[0151] In some embodiments, the target control mode combination can be determined according to the control mode of automatic power generation control, wherein the control modes include flat frequency control (FFC), flat tie-line control (FTC) and tie-line bias control (TBC). Primary frequency regulation is a differential regulation that cannot restore the grid frequency to the standard value, while secondary frequency regulation can achieve zero-difference regulation and more accurately maintain the stability of the system frequency. Secondary frequency regulation is mainly achieved through automatic generation control (AGC), in which the computer automatically controls the load of each power plant unit to achieve automation of the entire frequency regulation process. After considering the secondary frequency regulation, the asynchronous interconnected dual-area system can restore the grid frequencies on both sides to the standard value of the frequency, and the DC frequency controller is still effective in controlling the frequencies on both sides. For example, the frequency deviation is Figure 14As shown. In the control mode, the FFC mode means that the control target of the control area is to maintain the system frequency of the area at the set value, that is, to keep the frequency constant. The control target of the FTC mode is to maintain the constant exchange power of the tie line. The purpose of the TBC mode is to maintain the system frequency and tie line power within a predetermined range by controlling the tie line power between regions in a multi-region interconnected power system. In practical applications, the power system often adopts the FFC and TBC control modes. Therefore, in this embodiment, the DC frequency control characteristics under the FFC and TBC control modes will be analyzed.

[0152] Because different control modes have different control objectives, their regional control deviation (ACE) calculation methods are also different, and therefore their impact on grid frequency is also different. The regional control deviation of fixed frequency control can be calculated based on the frequency deviation and regional frequency deviation coefficient. The regional control deviation of tie line deviation control can be calculated based on the frequency deviation, regional frequency deviation coefficient, and the interconnected system tie line power. The calculation formula for the regional control deviation of fixed frequency control is: , the calculation formula for the regional control deviation of the tie line deviation control is: , where is the regional control deviation of constant frequency control, It is the regional control deviation of the tie line deviation control. is the regional frequency deviation coefficient, is the frequency deviation, is the interconnection system tie line power.

[0153] Then, according to the control mode, determine the combination of control modes to be selected, wherein the combination of control modes to be selected may include the first area being FFC+the second area being FFC, the first area being FFC+the second area being TBC, the first area being TBC+the second area being FFC, and the first area being TBC+the second area being TBC. Then, based on the proportional coefficient and the integral coefficient, calculate the relationship between the frequency change of the power grids on both sides of the asynchronous interconnected dual areas and the combination of control modes to be selected, and calculate the relationship between the DC transmission power participating in the frequency regulation and the combination of control modes to be selected. Finally, based on the regional control deviation of the fixed frequency control, the regional control deviation of the tie line deviation control, the relationship between the frequency change of the power grids on both sides of the asynchronous interconnected dual areas and the combination of control modes to be selected, and the relationship between the DC transmission power participating in the frequency regulation and the combination of control modes to be selected, perform an adaptive analysis of the automatic power generation control to obtain the target control mode combination. For example, it can be set , are the integral coefficients of the first and second regions of the AGC, respectively. When the absolute value of the coefficient is too large, it will cause system instability. It is usually set to about -0.3. Assuming that the integral coefficients of the AGC on both sides of the power grid are -0.3, the influence of different AGC control mode combinations on the frequency change of the power grids on both sides is analyzed, and the relationship between the frequency change of the power grids on both sides of the asynchronous interconnected dual-region and the combination of the selected control mode is obtained as follows: Figure 15 As shown in the figure, the relationship between the DC transmission power involved in frequency regulation and the combination of the selected control modes is as follows: Figure 16 shown. Figure 15 In the figure, the solid line represents the frequency deviation in the first region, and the dashed line represents the frequency deviation in the second region. When the TBC+FFC or TBC+TBC modes are used in the first and second regions, the maximum frequency deviation is slightly greater than that in the FFC+FFC or FFC+TBC modes. Furthermore, the TBC+TBC mode takes the shortest time for the grid frequencies on both sides to return to the standard value. Figure 16 In the example, the disturbance occurs in region 1, and the negative DC power involved in frequency regulation indicates that power needs to be transferred from region 2 to region 1 to achieve frequency support. When regions 1 and 2 adopt the TBC+FFC and TBC+TBC modes, the maximum DC power output is greater than that of the FFC+FFC and FFC+TBC modes. However, in the FFC+FFC mode, the DC regulated power involved in frequency regulation cannot be restored to zero. DC power recovery requires one side of the grid to adopt the TBC control mode, and the TBC+TBC mode takes the shortest time to restore power to zero. Therefore, the four AGC control mode combinations have similar control effects on the maximum frequency deviation and the maximum DC power involved in frequency regulation, while different combinations have different effects on the frequency recovery time and DC power recovery time. The TBC+TBC mode has the best control effect on frequency recovery and DC power recovery, and the TBC+TBC mode can be used as the target control mode combination.

[0154] In some embodiments, in step S105, dual-region frequency coordinated control can be performed based on the combination of control parameters and target control mode. For example, the calculated optimal proportional coefficient and the integral coefficient As a parameter, and combined with the optimal control mode combination (such as TBC+TBC mode) obtained by adaptability analysis as the target control mode combination, dual-area frequency coordinated control of the power system is performed.

[0155] In some embodiments, the method further comprises:

[0156] Conduct dual-region frequency coordinated control experiments;

[0157] Conducting a dual-region frequency coordinated control experiment includes the following steps:

[0158] In the asynchronous interconnected dual-region model, the grid capacity of the first region and the grid capacity of the second region are set;

[0159] The power disturbance in the first area, the power disturbance in the second area and the DC blocking fault are simulated and analyzed, and the frequency control experimental results are obtained.

[0160] In some embodiments, to verify the adaptability and regulation characteristics of the optimized DC frequency control under different operating conditions, a dual-area frequency coordinated control experiment can be conducted. An asynchronous interconnected dual-area model and a DC asynchronous interconnected dual-area model with AGC are constructed in Matlab / Simulink. The system frequency variations and DC frequency regulation power variations under three operating conditions are studied: a power disturbance in area one (i.e., the first area), a power disturbance in area two (i.e., the second area), and a DC blocking fault. The asynchronous interconnected dual-area model is first configured with the grid capacity of the first and second areas. Then, power disturbances in the first and second areas, as well as a DC blocking fault, are simulated and analyzed to obtain frequency control experimental results. For example, the grid capacity of the first area is set to 115,049 MW, and the grid capacity of the second area is set to 277,906 MW. Simulations are performed for the three operating conditions by adding a 1,000 MW power disturbance to the first and second areas at 5 seconds, and simulating a 1,000 MW DC blocking fault, thereby verifying the frequency control effectiveness of the DC frequency controller.

[0161] like Figures 17-25 As shown in the figure, the DC asynchronous interconnected dual-region model without AGC is simulated and analyzed. Figure 17 、 Figure 18 、 Figure 19 The frequency change on one side of the area, the frequency difference change on both sides, and the DC frequency modulation power change when a 1000MW power disturbance occurs in area 1; Figure 20 、 Figure 21 、 Figure 22 The frequency change on one side, the frequency difference change on both sides, and the DC frequency modulation power change when a 1000MW power disturbance occurs in area 2. Figure 23 、 Figure 24 、 Figure 25 The frequency change of one side, the frequency difference change of both sides and the DC frequency modulation power change under the 1000MW DC blocking fault are shown. The control parameters of the DC frequency controller are shown in Figure 2. The value is 1609. The value is 6136. Figure 17-Figure 19It can be seen that under the action of the DC frequency controller, the maximum grid frequency deviation is 0.009Hz, which is reduced to about a quarter of the maximum frequency deviation in the area without DC control. Moreover, the grid frequencies on both sides tend to be consistent 2.64s after the disturbance occurs, which is significantly improved compared to the regional frequency stabilization time without control. (In this embodiment, the stability range is 2% of the maximum frequency difference between the two sides after the disturbance occurs, that is, ) After the 1000MW disturbance occurred, the DC frequency modulation output power was reduced. During this process, part of the disturbance was distributed to the Region 2 power grid through the DC transmission line. The Region 2 power grid frequency modulation resources were used for rapid support to prevent further frequency deviation. Under the joint action of the generator sets and DC frequency modulation, a new power load balance state was reached, and the DC frequency modulation output power was stabilized at around 600MW. Figure 20-25 Similarly, the maximum frequency deviation under DC frequency modulation is effectively controlled, and the frequency regions of the two grids converge 2.06s and 1.87s after the disturbance, respectively. Comprehensive analysis shows that, under appropriate control parameters, the DC frequency controller can effectively address and rapidly respond to frequency variations under different disturbances and faults, and can quickly bring the frequencies of the two grids together, achieving mutual support between the two grids in the DC asynchronous interconnection and efficiently utilizing the frequency modulation resources of both grids.

[0162] like Figures 26-34 As shown in the figure, a simulation analysis of the DC asynchronous interconnected dual-region model with AGC is carried out. Figure 26 、 Figure 27 、 Figure 28 The frequency change on one side of the area, the frequency difference change on both sides, and the DC frequency modulation power change when a 1000MW power disturbance occurs in area 1; Figure 29 、 Figure 30 、 Figure 31 The frequency change on one side, the frequency difference change on both sides, and the DC frequency modulation power change when a 1000MW power disturbance occurs in area 2. Figure 32 、 Figure 33 、 Figure 34 The frequency change of one side of the area, the frequency difference change of both sides and the DC frequency modulation power change under the 1000MW DC blocking fault, among which the control parameters of the DC frequency controller are The value is 1609. The value is 6136, the AGC control mode adopts TBC+TBC combination, the integral coefficient and Take -0.3. Figure 26-Figure 28It can be seen that in the three scenarios, under the joint action of AGC, the maximum absolute value of the frequency deviation of the power grids on both sides of the asynchronous interconnection using the DC frequency controller is 0.010Hz, 0.009Hz and 0.007Hz respectively, which are all smaller than the absolute value of the maximum frequency deviation of the system without DC frequency control. In addition, due to the rapid action of the DC frequency modulation power, the frequency change rate of the power grid on the disturbance side is slightly reduced. Compared with the frequency change under DC frequency control without AGC control, it can be seen that the DC frequency control still has a good control effect after adding AGC. Under the action of the DC frequency controller, the frequency stabilization time is 2.96s, 5.07s and 2.67s respectively. The frequencies of the power grids on both sides of the asynchronous interconnection can quickly converge to achieve mutual support of the frequencies of the power grids on both sides. The DC frequency modulation power under different working conditions is as follows. Figures 31-34 As shown in Figure 2, in the TBC mode, the calculation of the regional frequency deviation ACE takes into account both the grid frequency deviation and the DC frequency modulation power, so the DC frequency modulation power can be gradually restored to 0 under the action of AGC.

[0163] The beneficial effects of implementing the embodiments of the present invention include: the embodiments of the present invention first obtain asynchronous interconnected dual-area information, then construct an asynchronous interconnected dual-area model based on the asynchronous interconnected dual-area information, and calculate control parameters based on the asynchronous interconnected dual-area model. Then, according to the control mode of automatic power generation control, the target control mode combination is determined. Finally, according to the control parameters and the target control mode combination, dual-area frequency coordinated control is performed, so that frequency coordinated control can be achieved by determining the optimal control parameters and control mode, thereby improving accuracy and frequency stability.

[0164] like Figure 35 As shown, an embodiment of the present invention further provides an asynchronous interconnected dual-region frequency coordinated control device, comprising:

[0165] The first module 801 is used to obtain asynchronous interconnected dual-region information;

[0166] The second module 802 is used to build an asynchronous interconnected dual-region model based on the asynchronous interconnected dual-region information;

[0167] The third module 803 is used to calculate the control parameters according to the asynchronous interconnected dual-region model, where the control parameters include a proportional coefficient and an integral coefficient;

[0168] The fourth module 804 is used to determine a target control mode combination according to the control mode of automatic power generation control, where the control mode includes constant frequency control, constant power control, and tie line deviation control;

[0169] The fifth module 805 is used to perform dual-region frequency coordinated control according to the combination of control parameters and target control mode.

[0170] The contents of the above method embodiments are all applicable to the present device embodiments. The functions specifically implemented by the present device embodiments are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.

[0171] like Figure 36 As shown, an embodiment of the present invention further provides a computer device, including:

[0172] at least one processor 901;

[0173] At least one memory 902, configured to store at least one program;

[0174] When at least one program is executed by at least one processor, the at least one processor implements Figure 1 The method shown.

[0175] The contents of the above method embodiments are all applicable to the present device embodiments. The functions specifically implemented by the present device embodiments are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.

[0176] The preferred embodiments of the present invention are described above with reference to the accompanying drawings, but are not intended to limit the scope of the present invention. Any modifications, equivalent substitutions, and improvements made by those skilled in the art without departing from the scope and essence of the present invention should be within the scope of the present invention.

Claims

1. A method for asynchronous interconnected dual-area frequency coordinated control, characterized in that: The following steps are involved: Get asynchronous interconnected dual-region information; Constructing an asynchronous interconnected dual-region model according to the asynchronous interconnected dual-region information; Calculating control parameters according to the asynchronous interconnected dual-region model, wherein the control parameters include a proportional coefficient and an integral coefficient; determining a target control mode combination according to a control mode of automatic power generation control, wherein the control mode includes constant frequency control, constant power control, and tie line deviation control; performing dual-region frequency coordinated control according to a combination of the control parameters and the target control mode; The step of calculating the control parameters according to the asynchronous interconnected dual-region model includes: Performing equivalent transformation on the asynchronous interconnected dual-region model to obtain a dual-region structure block diagram of the asynchronous interconnected system; Constructing a closed-loop system transfer function based on the dual-region structure block diagram of the asynchronous interconnected system and the power disturbance; constructing a denominator polynomial according to the closed-loop system transfer function; Constructing a system characteristic equation according to the denominator polynomial; Calculating closed-loop poles according to the system characteristic equation; According to the Routh criterion and the denominator polynomial, a Routh table is constructed; Constructing necessary and sufficient condition constraints for system stability based on the Routh table and the closed-loop poles; Calculate the relationship between system stability and control parameters based on the necessary and sufficient conditions for system stability; Determining a control parameter stability region based on the relationship between the system stability and the control parameter; Calculate the comprehensive stabilization time based on the step stabilization time; The control parameter is determined according to the asynchronous interconnection system parameter, the control parameter stability domain and the comprehensive stability time.

2. The method according to claim 1, characterized in that The step of constructing an asynchronous interconnected dual-region model according to the asynchronous interconnected dual-region information includes: Construct a steam turbine prime mover model based on the steam volume time constant; According to the time constant of water hammer effect, the turbine prime mover model is constructed; Constructing a DC frequency controller model according to the proportional coefficient and the integral coefficient; The asynchronous interconnected dual-region model is constructed according to the steam turbine prime mover model, the water turbine prime mover model, the DC frequency controller model, the asynchronous interconnected dual-region information, the hydropower unit regulation coefficient and the thermal power unit regulation coefficient.

3. The method according to claim 1, characterized in that The determining of the target control mode combination according to the control mode of the automatic power generation control includes: Calculating the regional control deviation of the fixed frequency control according to the frequency deviation and the regional frequency deviation coefficient; Calculating a regional control deviation of the tie-line deviation control according to the frequency deviation, the regional frequency deviation coefficient, and the interconnected system tie-line power; Determining a control mode combination to be selected according to the control mode; Calculating, based on the proportional coefficient and the integral coefficient, a relationship between a frequency change of the asynchronous interconnected dual-region power grid and the combination of the control modes to be selected; Calculating, based on the proportional coefficient and the integral coefficient, a relationship between the DC transmission power involved in frequency regulation and the combination of the control modes to be selected; Based on the regional control deviation of the fixed frequency control, the regional control deviation of the tie-line deviation control, the relationship between the frequency change of the asynchronous interconnected dual-region power grid and the candidate control mode combination, and the relationship between the DC transmission power participating in frequency regulation and the candidate control mode combination, an adaptive analysis of automatic power generation control is performed to obtain the target control mode combination.

4. The method according to claim 1, wherein The method further comprises: Conduct dual-region frequency coordinated control experiments; The dual-region frequency coordinated control experiment comprises the following steps: In the asynchronous interconnected dual-region model, setting the grid capacity of the first region and the grid capacity of the second region; The power disturbance in the first area, the power disturbance in the second area and the DC blocking fault are simulated and analyzed, and the frequency control experimental results are obtained.

5. The method according to claim 1, wherein The expression of the closed-loop system transfer function is: ， Where, is the closed-loop system transfer function with the power disturbance in the first region as input, is the Laplace transform of the frequency difference between the two regions, is the Laplace transform of the power disturbance in the first region, and are polynomial coefficients, , , is the complex variable in the Laplace transform, .

6. The method according to claim 1, characterized in that The calculation of the comprehensive stabilization time according to the step stabilization time includes: According to the step stabilization time, the comprehensive stabilization time is calculated by the comprehensive stabilization time calculation formula, which is: ， Where, is the comprehensive stabilization time, is the step settling time after the step disturbance occurs in the first region, is the step settling time after a step disturbance occurs in the second region.

7. The method according to claim 3, characterized in that Calculating the regional control deviation of the tie-line deviation control according to the frequency deviation, the regional frequency deviation coefficient, and the interconnected system tie-line power includes: According to the frequency deviation, the regional frequency deviation coefficient and the interconnected system tie line power, the regional control deviation of the tie line deviation control is calculated by the regional control deviation calculation formula of the tie line deviation control. The regional control deviation calculation formula of the tie line deviation control is: ， Where, is the regional control deviation of the tie line deviation control, is the regional frequency deviation coefficient, is the frequency deviation, is the tie line power of the interconnected system.

8. An asynchronous interconnected dual-region frequency coordinated control device, characterized in that: include: The first module is used to obtain asynchronous interconnected dual-region information; The second module is used to build an asynchronous interconnected dual-region model according to the asynchronous interconnected dual-region information; A third module is configured to calculate control parameters according to the asynchronous interconnected dual-region model, wherein the control parameters include a proportional coefficient and an integral coefficient; A fourth module is configured to determine a target control mode combination according to a control mode of automatic power generation control, wherein the control mode includes constant frequency control, constant power control, and tie line deviation control; A fifth module is configured to perform dual-region frequency coordinated control according to the control parameter and the target control mode combination; The step of calculating the control parameters according to the asynchronous interconnected dual-region model includes: Performing equivalent transformation on the asynchronous interconnected dual-region model to obtain a dual-region structure block diagram of the asynchronous interconnected system; Constructing a closed-loop system transfer function based on the dual-region structure block diagram of the asynchronous interconnected system and the power disturbance; constructing a denominator polynomial according to the closed-loop system transfer function; Constructing a system characteristic equation according to the denominator polynomial; Calculating closed-loop poles according to the system characteristic equation; According to the Routh criterion and the denominator polynomial, a Routh table is constructed; Constructing necessary and sufficient condition constraints for system stability based on the Routh table and the closed-loop poles; Calculate the relationship between system stability and control parameters based on the necessary and sufficient conditions for system stability; Determining a control parameter stability region based on the relationship between the system stability and the control parameter; Calculate the comprehensive stabilization time based on the step stabilization time; The control parameter is determined according to the asynchronous interconnection system parameter, the control parameter stability domain and the comprehensive stability time.

9. A computer device, characterized in that: include: at least one processor; at least one memory for storing at least one program; When the at least one program is executed by the at least one processor, the at least one processor implements the method according to any one of claims 1 to 7.

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