Parameter adaptive control method and apparatus for virtual synchronous generator, and electronic device

Abstract

A parameter adaptive control method and apparatus for a virtual synchronous generator, and an electronic device, relating to the technical field of voltage control. The method comprises: according to a coupling value of a direct current voltage change frequency band of a multi-terminal flexible direct current system during operation, constructing an adaptive direct current voltage droop coefficient function; according to a direct current voltage droop coefficient, calculating a damping ratio of an output port of the multi-terminal flexible direct current system, and according to the damping ratio of the output port and a preset damping ratio, constructing a first optimization objective function; according to differential-mode frequencies of a plurality of converter stations of the multi-terminal flexible direct current system, constructing a second optimization objective function; and constructing a parameter adaptive function according to a small signal model of the multi-terminal flexible direct current system, the first optimization objective function and the second optimization objective function, and solving the parameter adaptive function, so as to obtain a target parameter value of a virtual synchronous generator. The technical problem in the related art that multi-terminal flexible direct current systems exhibit poor stability when encountering disturbances is solved.

Description

Parameter adaptive control method and device of virtual synchronous generator and electronic equipment

[0001] The present application claims priority to the Chinese patent application No. 202411561533.7, filed on November 4, 2024, and entitled "Parameter adaptive control method and device of virtual synchronous generator and electronic equipment", the whole content of which is incorporated herein by reference. TECHNICAL FIELD

[0002] The present application relates to the technical field of voltage control, in particular to a parameter adaptive control method and device of a virtual synchronous generator and electronic equipment. BACKGROUND

[0003] In order to enhance the power transmission from remote renewable energy to load centers, the multi-terminal flexible DC technology based on voltage source converters has become an effective solution for large-scale offshore grid connection. The use of virtual synchronous generator control can enhance the frequency stability of the multi-terminal flexible DC system, and through parameter adaptation, the efficiency of the virtual synchronous generator control can be improved.

[0004] However, in the multi-terminal flexible DC system, the small disturbance stability of the virtual synchronous generator is challenged by the DC voltage control loop, increasing the complexity of virtual inertia and damping. Currently, the adaptive virtual synchronous generator parameter strategy in the related art has some limitations, for example, the adaptability of the voltage droop coefficient is ignored, the parameter coupling is increased by introducing an additional link, and the effectiveness of the control parameter adaptation is limited, resulting in poor stability of the multi-terminal flexible DC system when facing disturbances. In addition, some optimization methods are hindered by the limited parameter adjustment range, and the real-time calculation challenge appears in the global modeling-based method.

[0005] In view of the above problems, no effective solution has been proposed so far. SUMMARY

[0006] The present application provides a parameter adaptive control method and device of a virtual synchronous generator and electronic equipment to at least solve the technical problem that the parameter adaptive control strategy of the virtual synchronous generator used in the multi-terminal flexible DC system in the related art has limitations, resulting in poor stability of the multi-terminal flexible DC system when facing disturbances.

[0007] According to an aspect of the embodiment of the present application, a parameter adaptive control method of a virtual synchronous generator is provided, comprising: constructing an adaptive DC voltage droop coefficient function according to a coupling value of a DC voltage variation frequency band of a multi-terminal flexible DC system in a running process, wherein the adaptive DC voltage droop coefficient function is used to calculate a DC voltage droop coefficient; calculating a damping ratio of an output port of the multi-terminal flexible DC system according to the DC voltage droop coefficient, and constructing a first optimization objective function according to the damping ratio of the output port and a preset damping ratio, wherein the first optimization objective function is used to optimize a damping parameter; constructing a second optimization objective function according to a difference mode frequency of a plurality of converter stations of the multi-terminal flexible DC system, wherein the second optimization objective function is used to optimize an inertia parameter; constructing a parameter adaptive function according to a small signal model of the multi-terminal flexible DC system, the first optimization objective function and the second optimization objective function, and solving the parameter adaptive function to obtain a target parameter value of the virtual synchronous generator, wherein the target parameter value is used to adjust the virtual synchronous generator to realize parameter adaptive control.

[0008] Further, the adaptive DC voltage droop coefficient function is constructed according to the coupling value of the DC voltage variation frequency band of the multi-terminal flexible DC system in the running process, comprising: calculating the coupling value of the DC voltage variation frequency band according to a filtered value of a DC voltage variation rate of the multi-terminal flexible DC system in the running process, a dynamic relative gain array and a preset unit matrix; constructing the adaptive DC voltage droop coefficient function according to the coupling value of the DC voltage variation frequency band, a frequency variation rate of the multi-terminal flexible DC system, a frequency difference value and a gain coefficient.

[0009] Further, the damping ratio of the output port of the multi-terminal flexible DC system is calculated according to the DC voltage droop coefficient, comprising: calculating a first value according to a current damping coefficient, a DC capacitor system and a DC voltage value; calculating a second value according to a current inertia coefficient, the DC capacitor system, the DC voltage value, the DC voltage droop coefficient and a line parameter; calculating a ratio of the first value and the second value to obtain the damping ratio of the output port.

[0010] Further, the second optimization objective function is constructed according to the difference mode frequency of the plurality of converter stations of the multi-terminal flexible DC system, comprising: obtaining the difference mode frequency of each converter station and obtaining a weight between the converter stations; constructing the second optimization objective function according to the difference mode frequency of each converter station and the weight between the converter stations.

[0011] Further, the parameter adaptive function is constructed according to the small signal model of the multi-terminal flexible DC system, the first optimization objective function and the second optimization objective function, including: determining a dynamic output function of the multi-terminal flexible DC system according to the small signal model of the multi-terminal flexible DC system; obtaining a weighting coefficient matrix corresponding to the multi-terminal flexible DC system; and constructing the parameter adaptive function according to the weighting coefficient matrix, the dynamic output function of the multi-terminal flexible DC system, the small signal model of the multi-terminal flexible DC system, the first optimization objective function and the first optimization objective function.

[0012] Further, the parameter adaptive function is solved to obtain the target parameter value of the virtual synchronous generator, including: determining a constraint condition of the parameter adaptive function; and solving the parameter adaptive function based on the constraint condition by using a gradient descent method to obtain the target parameter value of the virtual synchronous generator.

[0013] Further, the target parameter value includes a target inertia coefficient and a target damping coefficient, and after the target parameter value of the virtual synchronous generator is obtained, the method further includes: adjusting the inertia coefficient and the damping coefficient of the virtual synchronous generator according to the target inertia coefficient and the target damping coefficient, respectively.

[0014] According to another aspect of the embodiment of the present application, a parameter adaptive control device of a virtual synchronous generator is also provided, including: a first processing module configured to construct an adaptive DC voltage droop coefficient function according to a coupling value of a DC voltage variation frequency band of a multi-terminal flexible DC system during operation, wherein the adaptive DC voltage droop coefficient function is used to calculate a DC voltage droop coefficient; a second processing module configured to calculate a damping ratio of an output port of the multi-terminal flexible DC system according to the DC voltage droop coefficient, and construct a first optimization objective function according to the damping ratio of the output port and a preset damping ratio, wherein the first optimization objective function is used to optimize a damping parameter; a third processing module configured to construct a second optimization objective function according to a difference mode frequency of a plurality of converter stations of the multi-terminal flexible DC system, wherein the second optimization objective function is used to optimize an inertia parameter; and a first determining module configured to construct a parameter adaptive function according to a small signal model of the multi-terminal flexible DC system, the first optimization objective function and the second objective function, and solve the parameter adaptive function to obtain a target parameter value of the virtual synchronous generator, wherein the target parameter value is used to adjust the virtual synchronous generator to realize parameter adaptive control.

[0015] According to another aspect of the embodiment of the present application, a computer program product is also provided, including a computer program, which, when executed by a processor, realizes the parameter adaptive control method of the virtual synchronous generator described above.

[0016] According to another aspect of the present invention, a computer-readable storage medium is also provided, wherein a computer program is stored in the computer program, wherein the computer program is configured to execute the above-described parameter adaptive control method for a virtual synchronous generator when it is run.

[0017] According to another aspect of the present invention, an electronic device is also provided, the electronic device including one or more processors; a memory for storing one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors are configured to run the programs, wherein the programs are configured to execute the above-described parameter adaptive control method for virtual synchronous generators during runtime.

[0018] In this embodiment of the invention, firstly, an adaptive DC voltage droop coefficient function is constructed based on the coupling value of the DC voltage variation frequency band during the operation of the multi-terminal flexible DC system. This adaptive DC voltage droop coefficient function is used to calculate the DC voltage droop coefficient. Then, the damping ratio of the output port of the multi-terminal flexible DC system is calculated based on the DC voltage droop coefficient. Based on the output port damping ratio and a preset damping ratio, a first optimization objective function is constructed. This first optimization objective function is used to optimize the damping parameters. Then, based on the differential mode frequencies of the multiple converter stations of the multi-terminal flexible DC system, a second optimization objective function is constructed. This second optimization objective function is used to optimize the inertial parameters. Finally, based on the small-signal model of the multi-terminal flexible DC system, the first optimization objective function, and the second optimization objective function, a parameter adaptive function is constructed and solved to obtain the target parameter values ​​of the virtual synchronous generator. These target parameter values ​​are used to adjust the virtual synchronous generator to achieve parameter adaptive control.

[0019] In the above process, an adaptive function for the DC voltage droop coefficient is constructed by quantizing and coupling DC voltage and AC power. An objective function for damping ratio and differential mode frequency consistency is constructed, and combined with the small-signal model of the multi-terminal flexible DC system, a parameter adaptive function is constructed, ultimately achieving adaptive control of the virtual synchronous generator parameters. By designing the adaptive function of the virtual synchronous generator for parameter optimization, including the DC voltage droop coefficient, inertia coefficient, and damping coefficient, the dynamic performance of the virtual synchronous generator control in the multi-terminal flexible DC system is improved. This enhances the system's adaptability and robustness in complex operating environments, balances the relationship between fast reference tracking and high virtual inertia, improves the mutual response of active power and angular frequency, effectively improves the stability of DC voltage and AC grid frequency in the multi-terminal flexible DC system, and enhances the system's response capability to AC grid frequency stability and load disturbances. This improves the overall stability and reliability of the power grid, and also increases real-time computation efficiency, avoiding the modeling and solving of the global system model.

[0020] Therefore, the technical solution of this invention achieves the goal of improving the operating efficiency and reliability of multi-terminal flexible DC systems, thereby improving the stability of multi-terminal flexible DC systems when facing disturbances. It also solves the technical problem that the parameter adaptive control strategy of virtual synchronous generators used in multi-terminal flexible DC systems has limitations, resulting in poor stability of multi-terminal flexible DC systems when facing disturbances. Attached Figure Description

[0021] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0022] Figure 1 is a flowchart of an optional parameter adaptive control method for a virtual synchronous generator according to an embodiment of the present invention;

[0023] Figure 2 is a schematic flowchart of an optional parameter adaptive control according to an embodiment of the present invention;

[0024] Figure 3 is a schematic diagram comparing the active power output using adaptive control and basic control under an optional load disturbance test according to an embodiment of the present invention;

[0025] Figure 4 is a schematic diagram comparing the frequency output of adaptive control and basic control under an optional load disturbance test according to an embodiment of the present invention;

[0026] Figure 5 is a schematic diagram comparing the DC-side voltage output using adaptive control and basic control under an optional load disturbance test according to an embodiment of the present invention;

[0027] Figure 6 is a schematic diagram comparing the active power output using adaptive control and basic control under an optional frequency disturbance test according to an embodiment of the present invention;

[0028] Figure 7 is a schematic diagram comparing the frequency output of adaptive control and basic control under an optional frequency disturbance test according to an embodiment of the present invention;

[0029] Figure 8 is a schematic diagram comparing the DC-side voltage output using adaptive control and basic control under an optional frequency disturbance test according to an embodiment of the present invention;

[0030] Figure 9 is a schematic diagram of an optional parameter adaptive control device for a virtual synchronous generator according to an embodiment of the present invention;

[0031] Figure 10 is a schematic diagram of an optional electronic device according to an embodiment of the present invention. Detailed Implementation

[0032] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0033] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0034] It should be noted that all relevant information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for display, data used for analysis, etc.) involved in this invention are information and data authorized by the user or fully authorized by all parties. For example, this system has an interface with the relevant user or organization. Before obtaining relevant information, it needs to send an acquisition request to the aforementioned user or organization through the interface, and obtain the relevant information after receiving consent from the aforementioned user or organization.

[0035] Example 1

[0036] According to an embodiment of the present invention, an embodiment of a parameter adaptive control method for a virtual synchronous generator is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0037] Figure 1 is a flowchart of an optional parameter adaptive control method for a virtual synchronous generator according to an embodiment of the present invention. As shown in Figure 1, the method includes the following steps:

[0038] Step S101: Based on the coupling value of the DC voltage change frequency band during the operation of the multi-terminal flexible DC system, an adaptive DC voltage droop coefficient function is constructed, wherein the adaptive DC voltage droop coefficient function is used to calculate the DC voltage droop coefficient.

[0039] In the above steps, the application system, processor, electronic equipment, etc. can be used as the execution subject. Optionally, the parameter adaptive control system of the virtual synchronous generator in the multi-terminal flexible DC system can be used as the execution subject.

[0040] Optionally, the coupling value of the DC voltage change frequency band during the operation of the multi-terminal flexible DC system is first solved, and an adaptive DC voltage droop coefficient function is constructed based on the coupling value of the DC voltage change frequency band during the operation of the multi-terminal flexible DC system.

[0041] In one optional embodiment, an adaptive DC voltage droop coefficient function is constructed based on the coupling value of the DC voltage change frequency band during the operation of the multi-terminal flexible DC system. This includes: calculating the coupling value of the DC voltage change frequency band based on the filtered value of the DC voltage change rate during the operation of the multi-terminal flexible DC system, the dynamic relative gain array, and the preset identity matrix; and constructing the adaptive DC voltage droop coefficient function based on the coupling value of the DC voltage change frequency band, the frequency change rate of the multi-terminal flexible DC system, the frequency difference, and the gain coefficient.

[0042] Optionally, based on the filtered value of the DC voltage change rate during the operation of the multi-terminal flexible DC system, the dynamic relative gain array, and the preset identity matrix, the coupling value f of the DC voltage change frequency band can be calculated. DR , is represented as follows: f DR =(||Λ D (v dc_LPF )-I 2×2 ||) / 4;

[0043] Among them, v dc_LPF Λ is the filter value for the DC voltage change rate. D (S) is a dynamic relative gain array, I 2×2 It is the identity matrix (i.e., the default identity matrix).

[0044] Optionally, based on the coupling value of the DC voltage variation frequency band, the frequency change rate of the multi-terminal flexible DC system, the frequency difference, and the gain coefficient, an adaptive DC voltage droop coefficient function is constructed, expressed as follows:

[0045] Among them, K dc K is the DC voltage droop factor. dc1 This represents the DC voltage droop coefficient at the previous moment. Let k be the frequency change rate of the multi-terminal flexible DC system, Δf be the frequency difference, and k be the frequency variation rate. d This is the gain coefficient.

[0046] Step S102: Calculate the damping ratio of the output port of the multi-terminal flexible DC system based on the DC voltage droop coefficient, and construct a first optimization objective function based on the output port damping ratio and the preset damping ratio, wherein the first optimization objective function is used to optimize the damping parameters.

[0047] Optionally, the preset damping ratio is a given value of the damping ratio, and the first optimization objective function is a damping parameter optimization objective function used to optimize the damping coefficient, with the goal of minimizing the difference between the output port damping ratio and the preset damping ratio.

[0048] Optionally, the damping ratio of the output port of the multi-terminal flexible DC system can be calculated based on the DC voltage droop coefficient, and an objective function for optimizing the damping parameters can be constructed based on the damping ratio of the output port and the preset damping ratio.

[0049] In one optional embodiment, the damping ratio of the output port of the multi-terminal flexible DC system is calculated based on the DC voltage droop coefficient, including: calculating a first value based on the current damping coefficient, the DC capacitor system, and the DC voltage value; calculating a second value based on the current inertia coefficient, the DC capacitor system, the DC voltage value, the DC voltage droop coefficient, and the line parameters; and calculating the ratio of the first value to the second value to obtain the damping ratio of the output port.

[0050] Optionally, based on the current damping coefficient D, the DC capacitor system C, and the DC voltage value v dc The first value obtained is denoted as: Dcv dc -1. Based on the current inertia coefficient J, DC capacitor system C, and DC voltage value v dc DC voltage droop coefficient K dc and line parameter k ij The calculated second value is expressed as:

[0051] The damping ratio ξ at the output port is calculated as follows:

[0052] Furthermore, the objective function for optimizing the damping parameters is constructed as follows:

[0053] Where, ξ ref β is the given value for the damping ratio, and β is the preset threshold.

[0054] Step S103: Based on the differential mode frequencies of multiple converter stations in the multi-terminal flexible DC system, a second optimization objective function is constructed, wherein the second optimization objective function is used to optimize the inertial parameters.

[0055] Optionally, the second optimization objective function is an inertial parameter optimization objective function, used to optimize the inertia coefficient. Based on the differential mode frequencies of the multiple converter stations in the multi-terminal flexible DC system, the inertial parameter optimization objective function can be constructed.

[0056] In one optional embodiment, a second optimization objective function is constructed based on the differential-mode frequencies of multiple converter stations in a multi-terminal flexible DC system, including: obtaining the differential-mode frequency of each converter station and obtaining the weights between converter stations; and constructing the second optimization objective function based on the differential-mode frequency of each converter station and the weights between converter stations.

[0057] Optionally, the differential-mode frequency of each converter station is first obtained, and the weights between the converter stations are also obtained. Then, based on the differential-mode frequency of each converter station and the weights between the converter stations, an objective function for optimizing the inertial parameters can be constructed, as follows:

[0058] Where, Δω doi (k) is the differential mode frequency of the i-th converter station, d ij The weight between the i-th converter station and the j-th converter station is calculated using the following formula:

[0059] If converter station i and converter station j have a communication link, then a ij =1, otherwise, a ij =0, N i This represents the total number of converter stations using parameter adaptive control.

[0060] Step S104: Based on the small-signal model of the multi-terminal flexible DC system, the first optimization objective function, and the second optimization objective function, construct the parameter adaptive function and solve the parameter adaptive function to obtain the target parameter values ​​of the virtual synchronous generator. The target parameter values ​​are used to adjust the virtual synchronous generator to achieve parameter adaptive control.

[0061] Optionally, the target parameters are the inertia coefficient and the damping coefficient. Based on the small-signal model of the multi-terminal flexible DC system, the damping parameter optimization objective function, and the inertia parameter optimization objective function, a parameter adaptive function is constructed. By solving the parameter adaptive function, the inertia coefficient and damping coefficient of the virtual synchronous generator can be obtained, thereby realizing parameter adaptive control.

[0062] Based on the scheme defined in steps S101 to S104 above, it can be understood that in this embodiment of the invention, firstly, an adaptive DC voltage droop coefficient function is constructed based on the coupling value of the DC voltage change frequency band during the operation of the multi-terminal flexible DC system. This adaptive DC voltage droop coefficient function is used to calculate the DC voltage droop coefficient. Then, the damping ratio of the output port of the multi-terminal flexible DC system is calculated based on the DC voltage droop coefficient. Based on the damping ratio of the output port and a preset damping ratio, a first optimization objective function is constructed. This first optimization objective function is used to optimize the damping parameters. Then, based on the differential mode frequency of the multiple converter stations of the multi-terminal flexible DC system, a second optimization objective function is constructed. This second optimization objective function is used to optimize the inertial parameters. Finally, based on the small-signal model of the multi-terminal flexible DC system, the first optimization objective function, and the second optimization objective function, a parameter adaptive function is constructed and solved to obtain the target parameter value of the virtual synchronous generator. This target parameter value is used to adjust the virtual synchronous generator to achieve parameter adaptive control.

[0063] It is noteworthy that, in the above process, an adaptive function for the DC voltage droop coefficient is constructed through the quantitative coupling of DC voltage and AC power. By constructing objective functions for damping ratio and differential mode frequency consistency, and combining this with the small-signal model of the multi-terminal flexible DC system, an adaptive parameter function is constructed, ultimately achieving the adaptive control parameters of the virtual synchronous generator. By designing the adaptive function of the virtual synchronous generator for parameter optimization, including the DC voltage droop coefficient, inertia coefficient, and damping coefficient, the dynamic performance of the virtual synchronous generator control in the multi-terminal flexible DC system is improved. This enhances the system's adaptability and robustness in complex operating environments, balances the relationship between fast reference tracking and high virtual inertia, improves the mutual response of active power and angular frequency, effectively improves the stability of DC voltage and AC grid frequency in the multi-terminal flexible DC system, and enhances the system's response capability to AC grid frequency stability and load disturbances. This, in turn, improves the overall stability and reliability of the power grid, and increases real-time computation efficiency, avoiding the modeling and solving of the global system model.

[0064] Therefore, the technical solution of this invention achieves the goal of improving the operating efficiency and reliability of multi-terminal flexible DC systems, thereby improving the stability of multi-terminal flexible DC systems when facing disturbances. It also solves the technical problem that the parameter adaptive control strategy of virtual synchronous generators used in multi-terminal flexible DC systems has limitations, resulting in poor stability of multi-terminal flexible DC systems when facing disturbances.

[0065] In one optional embodiment, a parameter adaptive function is constructed based on the small-signal model of the multi-terminal flexible DC system, the first optimization objective function, and the second optimization objective function, including: determining the dynamic output function of the multi-terminal flexible DC system based on the small-signal model of the multi-terminal flexible DC system; obtaining the weighting coefficient matrix corresponding to the multi-terminal flexible DC system; and constructing the parameter adaptive function based on the weighting coefficient matrix, the dynamic output function of the multi-terminal flexible DC system, the small-signal model of the multi-terminal flexible DC system, the first optimization objective function, and the second optimization objective function.

[0066] Optionally, the dynamic output function of the multi-terminal flexible DC system is first determined based on the small-signal model of the multi-terminal flexible DC system. Then, the weighting coefficient matrix corresponding to the multi-terminal flexible DC system is obtained. Based on the weighting coefficient matrix, the dynamic output function of the multi-terminal flexible DC system, the small-signal model of the multi-terminal flexible DC system, the damping parameter optimization objective function, and the inertial parameter optimization objective function, a parameter adaptive function is constructed, as follows:

[0067] Among them, G x (t) represents the small-signal model of a multi-terminal flexible DC system, r(G) x (t),u(t)) denote the dynamic output function of the multi-terminal flexible DC system. Let represent the weighting coefficient matrix, N represent the response time period, i represent the counting unit, and u(t) = [JD]. T `max` represents the operation of finding the maximum value, and `min` represents the operation of finding the minimum value.

[0068] In one optional embodiment, solving the parameter adaptive function to obtain the target parameter values ​​of the virtual synchronous generator includes: determining the constraints of the parameter adaptive function; and using the gradient descent method to solve the parameter adaptive function based on the constraints to obtain the target parameter values ​​of the virtual synchronous generator.

[0069] Optionally, the constraints of the adaptive parameter function are first determined, and then the gradient descent method can be used to solve the adaptive parameter function based on the constraints to obtain the inertia coefficient and damping coefficient of the virtual synchronous generator, as shown below:

[0070] Here, Ψ(Ω) represents the set of effective control parameters, i.e., constraints.

[0071] In one optional embodiment, the target parameter values ​​include a target inertia coefficient and a target damping coefficient. After obtaining the target parameter values ​​of the virtual synchronous generator, the inertia coefficient and damping coefficient of the virtual synchronous generator are adjusted according to the target inertia coefficient and the target damping coefficient, respectively.

[0072] Optionally, the target inertia coefficient is the inertia coefficient obtained by adaptive parameter solution, and the target damping coefficient is the damping coefficient obtained by adaptive parameter solution. The inertia coefficient and damping coefficient of the virtual synchronous generator are adjusted according to the target inertia coefficient and the target damping coefficient, respectively, thereby realizing adaptive parameter control.

[0073] In an optional embodiment, the flowchart shown in Figure 2 can be used to achieve parameter adaptive control. Figure 2 is a schematic flowchart of an optional parameter adaptive control according to an embodiment of the present invention. As shown in Figure 2, firstly, the coupling value of the system during dynamic operation is solved to construct an adaptive DC voltage droop coefficient function. Then, the damping ratio of the output port is calculated to construct a damping parameter optimization objective function. Then, an inertial parameter optimization objective function is constructed. Finally, a parameter adaptive function is constructed and solved to complete the parameter adaptive control. By performing coupling quantization processing on the multi-terminal flexible DC system containing the DC voltage control link, constraints are provided for the adaptive DC voltage droop coefficient. By solving the port damping value of the multi-terminal flexible DC system and reassigning it during the parameter adaptive process, damping constraints are provided. By interacting with the calculated differential mode frequency, rapid frequency convergence is achieved during the parameter adaptive process.

[0074] Optionally, a five-terminal flexible DC system model is built in the Matlab / Simulink environment to perform load disturbance and frequency disturbance tests. Load disturbance test: To simulate a step change in the power input of a virtual synchronous generator, the wind speed on the wind turbine side decreases at 10s. In this case, the grid-side converter station, based on the power received from the wind turbine side, according to K... dc Power is allocated based on the value of the parameter. Compared with the traditional virtual synchronous generator voltage control method, it exhibits good robust response in terms of active power, AC grid frequency, and DC side voltage response. Figure 3 is a schematic diagram comparing the active power output using adaptive control and basic control under an optional load disturbance test according to an embodiment of the present invention. As shown in Figure 3, although the response speed of virtual synchronous generator 1 (VSG1) is slower, this change is balanced by the advantage of minimizing overshoot. Under parameter adaptation, the system response of virtual synchronous generator 2 (VSG2) is faster. Although the response speed of virtual synchronous generator 3 (VSG3) is slower, the power drop is reduced. Due to the K value of the DC voltage loop of VSG3... dcThe value is the smallest, therefore, when a power disturbance occurs, the required output power is the smallest, and the impact of the change is also the smallest. Figure 4 is a schematic diagram comparing the frequency output using adaptive control and basic control under an optional load disturbance test according to an embodiment of the present invention. As shown in Figure 4, after adopting the adaptive strategy, the frequency drop of VSG1 and VSG3 in the multi-terminal flexible DC system is reduced. Figure 5 is a schematic diagram comparing the DC-side voltage output using adaptive control and basic control under an optional load disturbance test according to an embodiment of the present invention. As shown in Figure 5, the change in the DC-side voltage of the VSG is shown, and the improvement in voltage stability and the reduction in jitter can be seen.

[0075] Frequency Disturbance Test: To evaluate the performance of the parameter adaptive strategy under frequency disturbances, a load disturbance was introduced at t=10s to the grid-side converter station to simulate grid frequency fluctuations. When the load was introduced, the power output fluctuation of VSG1 was significantly reduced. Since the load disturbance occurred in the region of VSG1, and simultaneously, the K value of the DC voltage loop in VSG1... dc The value is the largest, therefore, the power change of VSG1 is large when load disturbance occurs, and the optimization effect is obvious. Figure 6 is a schematic diagram comparing the active power output using adaptive control and basic control under an optional frequency disturbance test according to an embodiment of the present invention. As shown in Figure 6, it shows that the adaptive algorithm effectively balances power fluctuations and improves the system's response capability and stability. Figure 7 is a schematic diagram comparing the frequency output using adaptive control and basic control under an optional frequency disturbance test according to an embodiment of the present invention. As shown in Figure 7, it illustrates the impact of load disturbances on the grid-side frequency. Under the action of the adaptive strategy, the frequency drop of all grid-side units is significantly alleviated. Figure 8 is a schematic diagram comparing the DC-side voltage output using adaptive control and basic control under an optional frequency disturbance test according to an embodiment of the present invention. As shown in Figure 8, it illustrates the DC-side voltage fluctuation, which is also reduced after adopting the adaptive method. These results show that the adaptive strategy not only optimizes the frequency response but also improves voltage stability, thereby enhancing the dynamic performance and stability of the entire system.

[0076] In this embodiment of the invention, firstly, an adaptive DC voltage droop coefficient function is constructed based on the coupling value of the DC voltage variation frequency band during the operation of the multi-terminal flexible DC system. This adaptive DC voltage droop coefficient function is used to calculate the DC voltage droop coefficient. Then, the damping ratio of the output port of the multi-terminal flexible DC system is calculated based on the DC voltage droop coefficient. Based on the output port damping ratio and a preset damping ratio, a first optimization objective function is constructed. This first optimization objective function is used to optimize the damping parameters. Then, based on the differential mode frequencies of the multiple converter stations of the multi-terminal flexible DC system, a second optimization objective function is constructed. This second optimization objective function is used to optimize the inertial parameters. Finally, based on the small-signal model of the multi-terminal flexible DC system, the first optimization objective function, and the second optimization objective function, a parameter adaptive function is constructed and solved to obtain the target parameter values ​​of the virtual synchronous generator. These target parameter values ​​are used to adjust the virtual synchronous generator to achieve parameter adaptive control.

[0077] In the above process, an adaptive function for the DC voltage droop coefficient is constructed by quantizing and coupling DC voltage and AC power. An objective function for damping ratio and differential mode frequency consistency is constructed, and combined with the small-signal model of the multi-terminal flexible DC system, a parameter adaptive function is constructed, ultimately achieving adaptive control of the virtual synchronous generator parameters. By designing the adaptive function of the virtual synchronous generator for parameter optimization, including the DC voltage droop coefficient, inertia coefficient, and damping coefficient, the dynamic performance of the virtual synchronous generator control in the multi-terminal flexible DC system is improved. This enhances the system's adaptability and robustness in complex operating environments, balances the relationship between fast reference tracking and high virtual inertia, improves the mutual response of active power and angular frequency, effectively improves the stability of DC voltage and AC grid frequency in the multi-terminal flexible DC system, and enhances the system's response capability to AC grid frequency stability and load disturbances. This improves the overall stability and reliability of the power grid, and also increases real-time computation efficiency, avoiding the modeling and solving of the global system model.

[0078] Therefore, the technical solution of this invention achieves the goal of improving the operating efficiency and reliability of multi-terminal flexible DC systems, thereby improving the stability of multi-terminal flexible DC systems when facing disturbances. It also solves the technical problem that the parameter adaptive control strategy of virtual synchronous generators used in multi-terminal flexible DC systems has limitations, resulting in poor stability of multi-terminal flexible DC systems when facing disturbances.

[0079] Example 2

[0080] According to an embodiment of the present invention, an embodiment of a parameter adaptive control device for a virtual synchronous generator is provided. FIG9 is a schematic diagram of an optional parameter adaptive control device for a virtual synchronous generator according to an embodiment of the present invention. As shown in FIG9, the device includes: a first processing module 901, used to construct an adaptive DC voltage droop coefficient function based on the coupling value of the DC voltage variation frequency band during the operation of the multi-terminal flexible DC system, wherein the adaptive DC voltage droop coefficient function is used to calculate the DC voltage droop coefficient; and a second processing module 902, used to calculate the damping ratio of the output port of the multi-terminal flexible DC system based on the DC voltage droop coefficient, and based on the output port… The first optimization objective function is constructed based on the damping ratio of the port and the preset damping ratio, whereby the first optimization objective function is used to optimize the damping parameters; the third processing module 903 is used to construct a second optimization objective function based on the differential mode frequency of multiple converter stations of the multi-terminal flexible DC system, whereby the second optimization objective function is used to optimize the inertial parameters; the first determination module 904 is used to construct a parameter adaptive function based on the small-signal model of the multi-terminal flexible DC system, the first optimization objective function and the second optimization objective function, and solve the parameter adaptive function to obtain the target parameter value of the virtual synchronous generator, whereby the target parameter value is used to adjust the virtual synchronous generator to achieve parameter adaptive control.

[0081] It should be noted that the first processing module 901, the second processing module 902, the third processing module 903 and the first determining module 904 mentioned above correspond to steps S101 to S104 in the above embodiments. The four modules and the corresponding steps implement the same examples and application scenarios, but are not limited to the content disclosed in the above embodiment 1.

[0082] Optionally, the first processing module includes: a first calculation module, used to calculate the coupling value of the DC voltage change frequency band based on the filtered value of the DC voltage change rate of the multi-terminal flexible DC system during operation, the dynamic relative gain array, and the preset identity matrix; and a first construction module, used to construct an adaptive DC voltage droop coefficient function based on the coupling value of the DC voltage change frequency band, the frequency change rate of the multi-terminal flexible DC system, the frequency difference, and the gain coefficient.

[0083] Optionally, the second processing module includes: a second calculation module for calculating a first value based on the current damping coefficient, DC capacitor system, and DC voltage value; a third calculation module for calculating a second value based on the current inertia coefficient, DC capacitor system, DC voltage value, DC voltage droop coefficient, and line parameters; and a fourth calculation module for calculating the ratio of the first value to the second value to obtain the damping ratio of the output port.

[0084] Optionally, the third processing module includes: a first acquisition module, used to acquire the differential mode frequency of each converter station and acquire the weights between converter stations; and a second construction module, used to construct a second optimization objective function based on the differential mode frequency of each converter station and the weights between converter stations.

[0085] Optionally, the first determining module includes: a second determining module, used to determine the dynamic output function of the multi-terminal flexible DC system based on the small-signal model of the multi-terminal flexible DC system; a second obtaining module, used to obtain the weighting coefficient matrix corresponding to the multi-terminal flexible DC system; and a third constructing module, used to construct a parameter adaptive function based on the weighting coefficient matrix, the dynamic output function of the multi-terminal flexible DC system, the small-signal model of the multi-terminal flexible DC system, the first optimization objective function, and the second optimization objective function.

[0086] Optionally, the first determining module further includes: a third determining module for determining the constraints of the parameter adaptive function; and a fourth determining module for solving the parameter adaptive function based on the constraints using the gradient descent method to obtain the target parameter values ​​of the virtual synchronous generator.

[0087] Optionally, the parameter adaptive control device for the virtual synchronous generator further includes: a fourth processing module, used to adjust the inertia coefficient and damping coefficient of the virtual synchronous generator according to the target inertia coefficient and the target damping coefficient after obtaining the target parameter values ​​of the virtual synchronous generator.

[0088] Example 3

[0089] According to another aspect of the present invention, a computer program product is also provided, including a computer program that, when executed by a processor, implements the above-described parameter adaptive control method for a virtual synchronous generator.

[0090] Example 4

[0091] According to another aspect of the present invention, a computer-readable storage medium is also provided, wherein a computer program is stored in the computer-readable storage medium, and the computer program is configured to execute the above-described parameter adaptive control method for a virtual synchronous generator when it is run.

[0092] Example 5

[0093] According to another aspect of the present invention, an electronic device is also provided, wherein FIG10 is a schematic diagram of an optional electronic device according to an embodiment of the present invention. As shown in FIG10, the electronic device includes one or more processors; a memory for storing one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors are configured to run the programs, wherein the programs are configured to execute the above-described parameter adaptive control method for virtual synchronous generators during runtime. When the processor executes the program, it performs the following steps: Based on the coupling value of the DC voltage variation frequency band during the operation of the multi-terminal flexible DC system, an adaptive DC voltage droop coefficient function is constructed, which is used to calculate the DC voltage droop coefficient; based on the DC voltage droop coefficient, the damping ratio of the output port of the multi-terminal flexible DC system is calculated, and based on the damping ratio of the output port and a preset damping ratio, a first optimization objective function is constructed, which is used to optimize the damping parameters; based on the differential mode frequencies of the multiple converter stations of the multi-terminal flexible DC system, a second optimization objective function is constructed, which is used to optimize the inertial parameters; based on the small-signal model of the multi-terminal flexible DC system, the first optimization objective function, and the second optimization objective function, a parameter adaptive function is constructed, and the parameter adaptive function is solved to obtain the target parameter values ​​of the virtual synchronous generator, which are used to adjust the virtual synchronous generator to achieve parameter adaptive control.

[0094] Optionally, the processor may also perform the following steps when executing the program: calculate the coupling value of the DC voltage change frequency band based on the filtered value of the DC voltage change rate of the multi-terminal flexible DC system during operation, the dynamic relative gain array, and the preset identity matrix; and construct an adaptive DC voltage droop coefficient function based on the coupling value of the DC voltage change frequency band, the frequency change rate of the multi-terminal flexible DC system, the frequency difference, and the gain coefficient.

[0095] Optionally, when the processor executes the program, it also performs the following steps: calculates a first value based on the current damping coefficient, DC capacitor system, and DC voltage value; calculates a second value based on the current inertia coefficient, DC capacitor system, DC voltage value, DC voltage droop coefficient, and line parameters; and calculates the ratio of the first value to the second value to obtain the damping ratio of the output port.

[0096] Optionally, the processor may also perform the following steps when executing the program: obtain the differential mode frequency of each converter station and obtain the weights between converter stations; construct a second optimization objective function based on the differential mode frequency of each converter station and the weights between converter stations.

[0097] Optionally, the processor may also perform the following steps when executing the program: determine the dynamic output function of the multi-terminal flexible DC system based on the small-signal model of the multi-terminal flexible DC system; obtain the weighting coefficient matrix corresponding to the multi-terminal flexible DC system; and construct a parameter adaptive function based on the weighting coefficient matrix, the dynamic output function of the multi-terminal flexible DC system, the small-signal model of the multi-terminal flexible DC system, the first optimization objective function, and the second optimization objective function.

[0098] Optionally, the processor may also perform the following steps when executing the program: determine the constraints of the parameter adaptive function; and use the gradient descent method to solve the parameter adaptive function based on the constraints to obtain the target parameter values ​​of the virtual synchronous generator.

[0099] Optionally, the processor may also perform the following steps when executing the program: after obtaining the target parameter values ​​of the virtual synchronous generator, adjust the inertia coefficient and damping coefficient of the virtual synchronous generator according to the target inertia coefficient and the target damping coefficient, respectively.

[0100] The devices mentioned in this article can be servers, PCs, tablets, mobile phones, etc.

[0101] 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.

[0102] 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.

[0103] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units can be a logical functional division, and in actual implementation, there may be other division methods. For instance, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling, direct coupling, or communication connection may be through some interfaces; the indirect coupling or communication connection between units or modules may be electrical or other forms.

[0104] 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 units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0105] 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.

[0106] 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 related technologies, 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 various media capable of storing program code, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0107] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A parameter adaptive control method for a virtual synchronous generator, characterized in that, Applications include multi-terminal flexible DC systems, including: Based on the coupling value of the DC voltage change frequency band during the operation of the multi-terminal flexible DC system, an adaptive DC voltage droop coefficient function is constructed, wherein the adaptive DC voltage droop coefficient function is used to calculate the DC voltage droop coefficient. The damping ratio of the output port of the multi-terminal flexible DC system is calculated based on the DC voltage droop coefficient, and a first optimization objective function is constructed based on the damping ratio of the output port and the preset damping ratio, wherein the first optimization objective function is used to optimize the damping parameters; Based on the differential mode frequencies of the multiple converter stations of the multi-terminal flexible DC system, a second optimization objective function is constructed, wherein the second optimization objective function is used to optimize the inertial parameters; Based on the small-signal model of the multi-terminal flexible DC system, the first optimization objective function, and the second optimization objective function, a parameter adaptive function is constructed and solved to obtain the target parameter values ​​of the virtual synchronous generator. The target parameter values ​​are used to adjust the virtual synchronous generator to achieve parameter adaptive control.

2. The method according to claim 1, characterized in that, Based on the coupling value of the DC voltage variation frequency band during the operation of the multi-terminal flexible DC system, an adaptive DC voltage droop coefficient function is constructed, including: Based on the filtered value of the DC voltage change rate, the dynamic relative gain array, and the preset identity matrix during the operation of the multi-terminal flexible DC system, the coupling value of the DC voltage change frequency band is calculated. Based on the coupling value of the DC voltage variation frequency band, the frequency variation rate of the multi-terminal flexible DC system, the frequency difference, and the gain coefficient, the adaptive DC voltage droop coefficient function is constructed.

3. The method according to claim 1, characterized in that, The damping ratio of the output port of the multi-terminal flexible DC system is calculated based on the DC voltage droop coefficient, including: The first value is calculated based on the current damping coefficient, DC capacitor system, and DC voltage value. The second value is calculated based on the current inertia coefficient, the DC capacitor system, the DC voltage value, the DC voltage droop coefficient, and the line parameters. The damping ratio of the output port is obtained by calculating the ratio of the first value to the second value.

4. The method according to claim 1, characterized in that, Based on the differential-mode frequencies of the multiple converter stations in the multi-terminal flexible DC system, a second optimization objective function is constructed, including: Obtain the differential mode frequency of each converter station and the weights between the converter stations; The second optimization objective function is constructed based on the differential mode frequency of each converter station and the weights between the converter stations.

5. The method according to claim 1, characterized in that, Based on the small-signal model of the multi-terminal flexible DC system, the first optimization objective function, and the second optimization objective function, a parameter adaptive function is constructed, including: The dynamic output function of the multi-terminal flexible DC system is determined based on the small-signal model of the multi-terminal flexible DC system. Obtain the weighting coefficient matrix corresponding to the multi-terminal flexible DC system; The parameter adaptive function is constructed based on the weighting coefficient matrix, the dynamic output function of the multi-terminal flexible DC system, the small-signal model of the multi-terminal flexible DC system, the first optimization objective function, and the second optimization objective function.

6. The method according to claim 1, characterized in that, Solving the parameter adaptive function yields the target parameter values ​​of the virtual synchronous generator, including: Determine the constraints of the parameter adaptive function; The target parameter values ​​of the virtual synchronous generator are obtained by solving the parameter adaptive function based on the constraints using the gradient descent method.

7. The method according to claim 1, characterized in that, The target parameter values ​​include the target inertia coefficient and the target damping coefficient. After obtaining the target parameter values ​​of the virtual synchronous generator, the method further includes: The inertia coefficient and damping coefficient of the virtual synchronous generator are adjusted according to the target inertia coefficient and the target damping coefficient, respectively.

8. A parameter adaptive control device for a virtual synchronous generator, characterized in that, Applications include multi-terminal flexible DC systems, including: The first processing module is used to construct an adaptive DC voltage droop coefficient function based on the coupling value of the DC voltage change frequency band during the operation of the multi-terminal flexible DC system, wherein the adaptive DC voltage droop coefficient function is used to calculate the DC voltage droop coefficient. The second processing module is used to calculate the damping ratio of the output port of the multi-terminal flexible DC system based on the DC voltage droop coefficient, and to construct a first optimization objective function based on the damping ratio of the output port and a preset damping ratio, wherein the first optimization objective function is used to optimize the damping parameters. The third processing module is used to construct a second optimization objective function based on the differential mode frequencies of the multiple converter stations of the multi-terminal flexible DC system, wherein the second optimization objective function is used to optimize the inertial parameters; The first determining module is used to construct a parameter adaptive function based on the small-signal model of the multi-terminal flexible DC system, the first optimization objective function, and the second optimization objective function, and solve the parameter adaptive function to obtain the target parameter values ​​of the virtual synchronous generator. The target parameter values ​​are used to adjust the virtual synchronous generator to achieve parameter adaptive control.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, wherein the computer program is configured to execute the parameter adaptive control method of the virtual synchronous generator according to any one of claims 1 to 7 when it is run.

10. An electronic device, characterized in that, The electronic device includes one or more processors; A memory for storing one or more programs, which, when executed by one or more processors, cause the one or more processors to run the programs, wherein the programs are configured to execute the parameter adaptive control method for the virtual synchronous generator as described in any one of claims 1 to 7.

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