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

Abstract

The invention discloses a parameter adaptive control method and device of a virtual synchronous generator and electronic equipment, and relates to the technical field of voltage control. The method comprises the following steps: constructing an adaptive DC voltage droop coefficient function according to a coupling value of a DC voltage change frequency band of the multi-terminal flexible DC system in an operation process; 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; constructing a second optimization objective function according to the differential mode frequencies of the plurality of converter stations of the multi-terminal flexible direct current system; and according to the small signal model of the multi-terminal flexible direct current system, the first optimization objective function and the second optimization objective function, constructing a parameter adaptive function, and solving the parameter adaptive function to obtain a target parameter value of the virtual synchronous generator. The technical problem that in the prior art, a multi-terminal flexible direct current system is poor in stability when facing disturbance is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of voltage control, and in particular to a parameter adaptive control method, device and electronic equipment for a virtual synchronous generator. Background Art

[0002] In order to enhance the power transmission from remote renewable energy sources to load centers, the multi-terminal flexible DC technology based on voltage source converter 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 the efficiency of virtual synchronous generator control can be improved through parameter adaptation.

[0003] However, in multi-terminal flexible DC systems, the DC voltage control loop poses a challenge to the small disturbance stability of the virtual synchronous generator, increasing the complexity of virtual inertia and damping. At present, there are some limitations in the adaptive virtual synchronous generator parameter strategy in the existing technology, such as ignoring the adaptability of the voltage droop coefficient, increasing parameter coupling by introducing additional links, and limiting the effectiveness of control parameter adaptation, resulting in poor stability of the multi-terminal flexible DC system in the face of disturbances. In addition, some optimization methods are hindered by the limited parameter adjustment range, and the global modeling-based methods present challenges in real-time calculation.

[0004] To address the above-mentioned problems, no effective solution has been proposed yet. Summary of the invention

[0005] The embodiments of the present invention provide a parameter adaptive control method, device and electronic device for a virtual synchronous generator, so as to at least solve the technical problem that the parameter adaptive control strategy of the virtual synchronous generator adopted in the multi-terminal flexible DC system in the prior art has limitations, resulting in poor stability of the multi-terminal flexible DC system when facing disturbances.

[0006] According to one aspect of an embodiment of the present invention, a parameter adaptive control method for 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 during operation, wherein the adaptive DC voltage droop coefficient function is used to calculate the DC voltage droop coefficient; obtaining the damping ratio of an output port of the multi-terminal flexible DC system according to the DC voltage droop coefficient calculation, 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 the damping parameter; constructing a second optimization objective function according to the differential mode frequencies of multiple converter stations of the multi-terminal flexible DC system, wherein the second optimization objective function is used to optimize the 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 achieve parameter adaptive control.

[0007] Furthermore, 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, including: calculating 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 the operation, the dynamic relative gain array and the preset unit matrix; constructing 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.

[0008] Furthermore, 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; calculating the ratio of the first value to the second value to obtain the damping ratio of the output port.

[0009] Furthermore, based on the differential mode frequencies of multiple converter stations in the multi-terminal flexible DC system, a second optimization objective function is constructed, including: obtaining the differential mode frequency of each converter station and obtaining the weights between the converter stations; based on the differential mode frequency of each converter station and the weights between the converter stations, a second optimization objective function is constructed.

[0010] Furthermore, 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 a weighting coefficient matrix corresponding to the multi-terminal flexible DC system; and constructing 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.

[0011] Furthermore, solving the parameter adaptive function to obtain the target parameter value of the virtual synchronous generator includes: determining the constraint conditions of the parameter adaptive function; using the gradient descent method to solve the parameter adaptive function based on the constraint conditions to obtain the target parameter value of the virtual synchronous generator.

[0012] Furthermore, the target parameter value includes a target inertia coefficient and a target damping coefficient, wherein, after obtaining the target parameter value of the virtual synchronous generator, 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.

[0013] According to another aspect of an embodiment of the present invention, a parameter adaptive control device for a virtual synchronous generator is also provided, comprising: a first processing module, used to construct an adaptive DC voltage droop coefficient function according to the coupling value of the DC voltage change frequency band of the multi-terminal flexible DC system during operation, wherein the adaptive DC voltage droop coefficient function is used to calculate the DC voltage droop coefficient; a second processing module, used to calculate the damping ratio of the 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 the damping parameter; a third processing module, used to construct a second optimization objective function according to the differential mode frequency of multiple converter stations of the multi-terminal flexible DC system, wherein the second optimization objective function is used to optimize the inertia parameter; a first determination module, used to construct a parameter adaptive function according to 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, wherein the target parameter value is used to adjust the virtual synchronous generator to achieve parameter adaptive control.

[0014] According to another aspect of an embodiment of the present invention, a computer program product is provided, including a computer program, and when the computer program is executed by a processor, the computer program implements the above-mentioned parameter adaptive control method of the virtual synchronous generator.

[0015] According to another aspect of an embodiment of the present invention, a computer-readable storage medium is provided, in which a computer program is stored, wherein the computer program is configured to execute the above-mentioned parameter adaptive control method of the virtual synchronous generator when running.

[0016] According to another aspect of an embodiment of the present invention, an electronic device is also provided, which includes one or more processors; a memory for storing one or more programs, which, when the one or more programs are executed by the one or more processors, enables the one or more processors to run the programs, wherein the programs are configured to execute the above-mentioned parameter adaptive control method of the virtual synchronous generator when running.

[0017] In an embodiment of the present invention, first, an adaptive DC voltage droop coefficient function is constructed according to the coupling value of the DC voltage change frequency band of the multi-terminal flexible DC system during operation, wherein the adaptive DC voltage droop coefficient function is used to calculate the DC voltage droop coefficient, and then the damping ratio of the output port of the multi-terminal flexible DC system is calculated according to the DC voltage droop coefficient, and according to the damping ratio of the output port and the preset damping ratio, a first optimization objective function is constructed, wherein the first optimization objective function is used to optimize the damping parameter, and then according to the differential mode frequency of 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 inertia parameter, and then according to 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 value of the virtual synchronous generator, wherein the target parameter value is used to adjust the virtual synchronous generator to achieve parameter adaptive control.

[0018] In the above process, by quantitatively coupling DC voltage and AC power, an adaptive function of DC voltage droop coefficient is constructed. By constructing the objective function of damping ratio and differential mode frequency consistency, combined with the small signal model of multi-terminal flexible DC system, a parameter adaptive function is constructed, and finally the adaptation of virtual synchronous generator control parameters is completed. By designing the adaptive function of virtual synchronous generator for parameter optimization, including DC voltage drop coefficient, inertia coefficient and damping coefficient, the dynamic performance of virtual synchronous generator control in multi-terminal flexible DC system is improved, the adaptability and robustness of the system in complex operating environment are improved, the relationship between fast reference tracking and high virtual inertia is balanced, the mutual response of active power and angular frequency is improved, the stability of DC voltage and AC grid frequency in multi-terminal flexible DC system is effectively improved, and the system's response to AC grid frequency stability and load disturbance is enhanced, thereby improving the stability and reliability of the entire power grid, and improving the real-time computing efficiency, avoiding the modeling and solution of the global system model.

[0019] It can be seen that through the technical solution of the present invention, the purpose of improving the operating efficiency and reliability of the multi-terminal flexible DC system is achieved, thereby achieving the technical effect of improving the stability of the multi-terminal flexible DC system in the face of disturbances, and further solving the technical problem that the parameter adaptive control strategy of the virtual synchronous generator adopted in the multi-terminal flexible DC system in the prior art has limitations, resulting in poor stability of the multi-terminal flexible DC system in the face of disturbances. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0021] Figure 1 is a flow chart of an optional parameter adaptive control method of a virtual synchronous generator according to an embodiment of the present invention;

[0022] Figure 2 is a schematic diagram of an optional parameter adaptive control process according to an embodiment of the present invention;

[0023] Figure 3 is a schematic diagram of active power output comparison using adaptive control and basic control under an optional load disturbance test according to an embodiment of the present invention;

[0024] Figure 4 is a schematic diagram of frequency output comparison using adaptive control and basic control under an optional load disturbance test according to an embodiment of the present invention;

[0025] Figure 5 is a schematic diagram of a comparison of DC side voltage output using adaptive control and basic control under an optional load disturbance test according to an embodiment of the present invention;

[0026] Figure 6 is a schematic diagram of active power output comparison using adaptive control and basic control under an optional frequency disturbance test according to an embodiment of the present invention;

[0027] Figure 7 is a schematic diagram of frequency output comparison using adaptive control and basic control under an optional frequency disturbance test according to an embodiment of the present invention;

[0028] Figure 8 is a schematic diagram of comparison of DC side voltage output using adaptive control and basic control under an optional frequency disturbance test according to an embodiment of the present invention;

[0029] Fig. 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;

[0030] Fig.10 is a schematic diagram of an optional electronic device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0031] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0032] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0033] It should be noted that the relevant information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data for display, data for analysis, etc.) involved in the present invention are all information and data authorized by the user or fully authorized by all parties. For example, an interface is set between the system and the relevant user or organization. Before obtaining relevant information, it is necessary to send an acquisition request to the aforementioned user or organization through the interface, and obtain relevant information after receiving the consent information fed back by the aforementioned user or organization.

[0034] Example 1

[0035] According to an embodiment of the present invention, an embodiment of a parameter adaptive control method of a virtual synchronous generator is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0036] Figure 1 is a flow chart of an optional parameter adaptive control method of a virtual synchronous generator according to an embodiment of the present invention, such as Figure 1 As shown, the method comprises the following steps:

[0037] Step S101 : constructing an adaptive DC voltage droop coefficient function according to the coupling value of the DC voltage variation frequency band of the multi-terminal flexible DC system during operation, wherein the adaptive DC voltage droop coefficient function is used to calculate the DC voltage droop coefficient.

[0038] In the above steps, the application system, processor, electronic device and other devices may be used as the execution subject. Optionally, the parameter adaptive control system of the virtual synchronous generator in the multi-terminal flexible DC system may be used as the execution subject.

[0039] Optionally, firstly, a coupling value of a DC voltage variation frequency band of the multi-terminal flexible DC system during operation is solved, and an 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 during operation.

[0040] In an optional embodiment, an adaptive DC voltage droop coefficient function is constructed based on a coupling value of a DC voltage change frequency band during operation of a multi-terminal flexible DC system, including: calculating the coupling value of the DC voltage change frequency band based on a filtered value of a DC voltage change rate of the multi-terminal flexible DC system during operation, a dynamic relative gain array, and a preset unit matrix; constructing 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.

[0041] Optionally, the coupling value f of the DC voltage change frequency band can be calculated 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 unit matrix. DR , which is expressed as follows:

[0042] f DR =(||Λ D (v dc_LPF )-I 2×2 ||) / 4

[0043] Among them, v dc_LPF is the filtered value of the DC voltage change rate, Λ D (S) is the dynamic relative gain array, I 2×2 is the unit matrix (i.e., the preset unit matrix).

[0044] Optionally, an adaptive DC voltage droop coefficient function is constructed according to 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, which is expressed as follows:

[0045]

[0046] Among them, K dc is the DC voltage droop coefficient, K dc1 is the DC voltage droop coefficient at the previous moment, is the frequency change rate of the multi-terminal flexible DC system, Δf is the frequency difference, k d is the gain factor.

[0047] Step S102, calculating the damping ratio of the 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 the damping parameters.

[0048] 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, which is used to optimize the damping coefficient with the goal of minimizing the difference between the damping ratio of the output port and the preset damping ratio.

[0049] 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 a damping parameter optimization objective function can be constructed based on the damping ratio of the output port and a preset damping ratio.

[0050] In an 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; calculating the ratio of the first value to the second value to obtain the damping ratio of the output port.

[0051] Optionally, according to the current damping coefficient D, the DC capacitor system C and the DC voltage value v dc The first value is calculated and expressed as: DCv dc -1. Based on the current inertia coefficient J, DC capacitor system C, DC voltage value v dc , DC voltage droop coefficient K dc And the line parameter k ij The second value is calculated and expressed as:

[0052] Calculate the damping ratio ξ of the output port, expressed as follows:

[0053]

[0054] Furthermore, the damping parameter optimization objective function is constructed as follows:

[0055]

[0056] Among them, ξ ref is the given value of the damping ratio, and β is the preset threshold.

[0057] Step S103: constructing a second optimization objective function according to the differential mode frequencies of multiple converter stations of the multi-terminal flexible DC system, wherein the second optimization objective function is used to optimize the inertia parameters.

[0058] Optionally, the second optimization objective function is an inertia parameter optimization objective function, which is used to optimize the inertia coefficient. According to the differential mode frequencies of multiple converter stations of the multi-terminal flexible DC system, an inertia parameter optimization objective function can be constructed.

[0059] In an optional embodiment, a second optimization objective function is constructed based on the differential mode frequencies of multiple converter stations in the multi-terminal flexible DC system, including: obtaining the differential mode frequency of each converter station and obtaining the weights between the converter stations; and constructing the second optimization objective function based on the differential mode frequency of each converter station and the weights between the converter stations.

[0060] Optionally, firstly, the differential mode frequency of each converter station is obtained, and the weights between the converter stations are obtained. Then, according to the differential mode frequency of each converter station and the weights between the converter stations, an inertia parameter optimization objective function can be constructed, which is expressed as follows:

[0061]

[0062] Among them, Δω doi (k) is the differential mode frequency of the i-th converter station, d ij is the weight between the i-th converter station and the j-th converter station, and the calculation formula is:

[0063]

[0064] If there is a communication link between converter station i and converter station j, then a ij =1, otherwise, a ij =0,N i is the total number of converter stations using parameter adaptive control.

[0065] Step S104, constructing 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 solving the parameter adaptive function to obtain the target parameter value of the virtual synchronous generator, wherein the target parameter value is used to adjust the virtual synchronous generator to achieve parameter adaptive control.

[0066] Optionally, the target parameter values ​​are the inertia coefficient and the damping coefficient. According to 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, and the parameter adaptive function is solved to obtain the inertia coefficient and the damping coefficient of the virtual synchronous generator, thereby realizing parameter adaptive control.

[0067] Based on the scheme defined by the above steps S101 to S104, it can be known that in an embodiment of the present invention, first, an adaptive DC voltage droop coefficient function is constructed according to the coupling value of the DC voltage change frequency band of the multi-terminal flexible DC system during operation, wherein the adaptive DC voltage droop coefficient function is used to calculate the DC voltage droop coefficient, and then the damping ratio of the output port of the multi-terminal flexible DC system is calculated according to the DC voltage droop coefficient, and a first optimization objective function is constructed according to the damping ratio of the output port and the preset damping ratio, wherein the first optimization objective function is used to optimize the damping parameter, and then a second optimization objective function is constructed according to the differential mode frequency of multiple converter stations of the multi-terminal flexible DC system, wherein the second optimization objective function is used to optimize the inertia parameter, and then a 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, and the parameter adaptive function is solved to obtain the target parameter value of the virtual synchronous generator, wherein the target parameter value is used to adjust the virtual synchronous generator to achieve parameter adaptive control.

[0068] It is easy to notice that in the above process, by quantizing the coupling of DC voltage and AC power, an adaptive function of DC voltage droop coefficient is constructed, and by constructing the objective function of damping ratio and differential mode frequency consistency, combined with the small signal model of the multi-terminal flexible DC system, a parameter adaptive function is constructed, and finally the adaptation of the control parameters of the virtual synchronous generator is completed. By designing the adaptive function of the virtual synchronous generator for parameter optimization, including DC voltage drop coefficient, inertia coefficient and damping coefficient, the dynamic performance of the virtual synchronous generator control of the multi-terminal flexible DC system is improved, the adaptability and robustness of the system in the face of complex operating environments are improved, the relationship between fast reference tracking and high virtual inertia is balanced, the mutual response of active power and angular frequency is improved, and the stability of DC voltage and AC grid frequency in the multi-terminal flexible DC system is effectively improved. The system's response to AC grid frequency stability and load disturbances is enhanced, thereby improving the stability and reliability of the entire power grid, and improving the real-time computing efficiency, avoiding the modeling and solution of the global system model.

[0069] It can be seen that through the technical solution of the present invention, the purpose of improving the operating efficiency and reliability of the multi-terminal flexible DC system is achieved, thereby achieving the technical effect of improving the stability of the multi-terminal flexible DC system in the face of disturbances, and further solving the technical problem that the parameter adaptive control strategy of the virtual synchronous generator adopted in the multi-terminal flexible DC system in the prior art has limitations, resulting in poor stability of the multi-terminal flexible DC system in the face of disturbances.

[0070] In an optional embodiment, a parameter adaptive function is constructed based on a small signal model of a multi-terminal flexible DC system, a first optimization objective function and a second optimization objective function, including: determining a dynamic output function of the multi-terminal flexible DC system based on 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 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.

[0071] Optionally, firstly, the dynamic output function of the multi-terminal flexible DC system is determined according to the small signal model of the multi-terminal flexible DC system, and then the weight coefficient matrix corresponding to the multi-terminal flexible DC system is obtained. According to the weight 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 inertia parameter optimization objective function, a parameter adaptive function is constructed, which is expressed as follows:

[0072]

[0073] Among them, G x (t) represents the small signal model of the multi-terminal flexible DC system, r(G x (t),u(t)) represents the dynamic output function of the multi-terminal flexible DC system, represents the weighting coefficient matrix, N represents the response time period of the operation, i represents the counting unit, u(t)=[JD] T , max means the operation of taking the maximum value, and min means the operation of taking the minimum value.

[0074] In an optional embodiment, solving the parameter adaptive function to obtain the target parameter value of the virtual synchronous generator includes: determining the constraint conditions of the parameter adaptive function; using a gradient descent method to solve the parameter adaptive function based on the constraint conditions to obtain the target parameter value of the virtual synchronous generator.

[0075] Optionally, the constraint conditions of the parameter adaptive function are first determined, and then the gradient descent method can be used to solve the parameter adaptive function based on the constraint conditions to obtain the inertia coefficient and damping coefficient of the virtual synchronous generator, which are expressed as follows:

[0076]

[0077] Among them, Ψ(Ω) represents the set of effective control parameters, that is, constraints.

[0078] In an optional embodiment, the target parameter value includes a target inertia coefficient and a target damping coefficient. After the target parameter value of the virtual synchronous generator is obtained, the inertia coefficient and the damping coefficient of the virtual synchronous generator are adjusted according to the target inertia coefficient and the target damping coefficient.

[0079] Optionally, the target inertia coefficient is the inertia coefficient obtained by parameter adaptive solution, and the target damping coefficient is the damping coefficient obtained by parameter adaptive 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, to achieve parameter adaptive control.

[0080] In an optional embodiment, it is possible to use Figure 2 The flowchart shown in the figure realizes parameter adaptive control. Figure 2 is a schematic diagram of an optional parameter adaptive control process according to an embodiment of the present invention, such as Figure 2 As shown in the figure, firstly, the coupling value of the system in dynamic operation is solved, and the adaptive DC voltage droop coefficient function is constructed. Then, the damping ratio of the output port is calculated, and the damping parameter optimization objective function is constructed. Then, the inertia parameter optimization objective function is constructed, and then the parameter adaptive function is constructed. The parameter adaptive function is solved to complete the parameter adaptive control. By performing coupled quantization processing of DC voltage and AC power on the multi-terminal flexible DC system with DC voltage control link, constraint conditions are provided for the DC voltage droop coefficient adaptation; by solving the port damping value of the multi-terminal flexible DC system and reassigning it in the parameter adaptive process, damping constraints are provided; by interacting with the calculated differential mode frequency, the frequency convergence is achieved quickly in the parameter adaptive process.

[0081] Optionally, a five-terminal flexible DC system model is built in the Matlab / Simulink environment to perform load disturbance tests and frequency disturbance tests. Load disturbance test: To simulate the step change of the power input of the virtual synchronous generator, the wind speed on the wind power side decreases at 10s. In this case, the grid-side converter station receives the power from the wind power side and calculates the frequency disturbance test according to K. dc The power is distributed according to the value of. Compared with the traditional virtual synchronous generator voltage control method, it shows good robust response in terms of active power, AC grid frequency and DC side voltage response. Figure 3 is a schematic diagram of comparing active power output using adaptive control and basic control under an optional load disturbance test according to an embodiment of the present invention, such as Figure 3As shown in the figure, although the response speed of virtual synchronous generator 1 (VSG1) slows down, 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) slows down, the power drop is reduced. dc The value is the smallest. Therefore, when a power disturbance occurs, the output power required to respond is the smallest, and the impact of the change is also the smallest. Figure 4 is a schematic diagram of frequency output comparison using adaptive control and basic control under an optional load disturbance test according to an embodiment of the present invention, such as Figure 4 As shown in the figure, after adopting the adaptive strategy, the frequency drop degree of VSG1 and VSG3 in the multi-terminal flexible DC system is reduced. Figure 5 is a schematic diagram of a comparison of DC side voltage output using adaptive control and basic control under an optional load disturbance test according to an embodiment of the present invention, such as Figure 5 As shown, the change of the VSG DC side voltage is shown, and it can be seen that the voltage stability is improved and the jitter is reduced.

[0082] Frequency disturbance test: In order to evaluate the performance of the parameter adaptation strategy under frequency disturbance, a load disturbance was introduced to the grid-side converter station at t = 10s to simulate the scenario of grid frequency fluctuation. When the load was introduced, the fluctuation of VSG1 power output was significantly reduced. Since the load disturbance occurred in the area of ​​VSG1, and at the same time, the K of the DC voltage loop in VSG1 dc The value is the largest. Therefore, when load disturbance occurs, the power variation of VSG1 is large and the optimization effect is obvious. Figure 6 is a schematic diagram of comparing active power output using adaptive control and basic control under an optional frequency disturbance test according to an embodiment of the present invention, such as Figure 6 As shown, it shows that the adaptive algorithm effectively balances the power fluctuations and improves the system's responsiveness and stability. Figure 7 FIG. 1 is a schematic diagram of frequency output comparison using adaptive control and basic control under an optional frequency disturbance test according to an embodiment of the present invention. Figure 7 As shown in the figure, the impact of load disturbance on the grid frequency is demonstrated. Under the action of the adaptive strategy, the frequency drop of all units on the grid side is significantly alleviated. Figure 8 is a schematic diagram of a comparison of DC side voltage output using adaptive control and basic control under an optional frequency disturbance test according to an embodiment of the present invention, such as Figure 8 As shown in Figure 2, the DC side voltage fluctuation is shown, and after the adaptive method is adopted, the fluctuation is also reduced. These results show that the adaptive strategy not only optimizes the frequency response, but also improves the voltage stability, thereby enhancing the dynamic performance and stability of the entire system.

[0083] In an embodiment of the present invention, first, an adaptive DC voltage droop coefficient function is constructed according to the coupling value of the DC voltage change frequency band of the multi-terminal flexible DC system during operation, wherein the adaptive DC voltage droop coefficient function is used to calculate the DC voltage droop coefficient, and then the damping ratio of the output port of the multi-terminal flexible DC system is calculated according to the DC voltage droop coefficient, and according to the damping ratio of the output port and the preset damping ratio, a first optimization objective function is constructed, wherein the first optimization objective function is used to optimize the damping parameter, and then according to the differential mode frequency of 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 inertia parameter, and then according to 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 value of the virtual synchronous generator, wherein the target parameter value is used to adjust the virtual synchronous generator to achieve parameter adaptive control.

[0084] In the above process, by quantitatively coupling DC voltage and AC power, an adaptive function of DC voltage droop coefficient is constructed. By constructing the objective function of damping ratio and differential mode frequency consistency, combined with the small signal model of multi-terminal flexible DC system, a parameter adaptive function is constructed, and finally the adaptation of virtual synchronous generator control parameters is completed. By designing the adaptive function of virtual synchronous generator for parameter optimization, including DC voltage drop coefficient, inertia coefficient and damping coefficient, the dynamic performance of virtual synchronous generator control in multi-terminal flexible DC system is improved, the adaptability and robustness of the system in complex operating environment are improved, the relationship between fast reference tracking and high virtual inertia is balanced, the mutual response of active power and angular frequency is improved, the stability of DC voltage and AC grid frequency in multi-terminal flexible DC system is effectively improved, and the system's response to AC grid frequency stability and load disturbance is enhanced, thereby improving the stability and reliability of the entire power grid, and improving the real-time computing efficiency, avoiding the modeling and solution of the global system model.

[0085] It can be seen that through the technical solution of the present invention, the purpose of improving the operating efficiency and reliability of the multi-terminal flexible DC system is achieved, thereby achieving the technical effect of improving the stability of the multi-terminal flexible DC system in the face of disturbances, and further solving the technical problem that the parameter adaptive control strategy of the virtual synchronous generator adopted in the multi-terminal flexible DC system in the prior art has limitations, resulting in poor stability of the multi-terminal flexible DC system in the face of disturbances.

[0086] Example 2

[0087] According to an embodiment of the present invention, an embodiment of a parameter adaptive control device for a virtual synchronous generator is provided, wherein: Fig. 9is a schematic diagram of an optional parameter adaptive control device for a virtual synchronous generator according to an embodiment of the present invention, such as Fig. 9 As shown, the device includes: a first processing module 901, which is used to construct an adaptive DC voltage droop coefficient function according to the coupling value of the DC voltage change frequency band of the multi-terminal flexible DC system during operation, wherein the adaptive DC voltage droop coefficient function is used to calculate the DC voltage droop coefficient; a second processing module 902, which is used to calculate the damping ratio of the 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 the damping parameter; a third processing module 903, which is used to construct a second optimization objective function according to the differential mode frequency of multiple converter stations of the multi-terminal flexible DC system, wherein the second optimization objective function is used to optimize the inertia parameter; a first determination module 904, which is used to construct a parameter adaptive function according to 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, wherein the target parameter value is used to adjust the virtual synchronous generator to achieve parameter adaptive control.

[0088] It should be noted that the above-mentioned first processing module 901, second processing module 902, third processing module 903 and first determination module 904 correspond to steps S101 to S104 in the above-mentioned embodiment, and the examples and application scenarios implemented by the four modules and the corresponding steps are the same, but are not limited to the contents disclosed in the above-mentioned embodiment 1.

[0089] 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 unit matrix; 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.

[0090] Optionally, the second processing module includes: a second calculation module, used to calculate the first value based on the current damping coefficient, DC capacitor system and DC voltage value; a third calculation module, used to calculate the second value based on the current inertia coefficient, DC capacitor system, DC voltage value, DC voltage droop coefficient and line parameters; a fourth calculation module, used to calculate the ratio of the first value to the second value to obtain the damping ratio of the output port.

[0091] Optionally, the third processing module includes: a first acquisition module, used to obtain the differential mode frequency of each converter station and obtain the weights between the 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 the converter stations.

[0092] Optionally, the first determination module includes: a second determination 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 acquisition module, used to obtain a weighting coefficient matrix corresponding to the multi-terminal flexible DC system; and a third construction 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.

[0093] Optionally, the first determination module also includes: a third determination module, used to determine the constraints of the parameter adaptive function; and a fourth determination module, used to solve the parameter adaptive function based on the constraints using a gradient descent method to obtain a target parameter value of the virtual synchronous generator.

[0094] Optionally, the parameter adaptive control device of the virtual synchronous generator also includes: a fourth processing module, which is 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 value of the virtual synchronous generator.

[0095] Example 3

[0096] According to another aspect of an embodiment of the present invention, a computer program product is provided, including a computer program, and when the computer program is executed by a processor, the computer program implements the above-mentioned parameter adaptive control method of the virtual synchronous generator.

[0097] Example 4

[0098] According to another aspect of an embodiment of the present invention, a computer-readable storage medium is provided, in which a computer program is stored, wherein the computer program is configured to execute the above-mentioned parameter adaptive control method of the virtual synchronous generator when running.

[0099] Example 5

[0100] According to another aspect of an embodiment of the present invention, there is also provided an electronic device, wherein: Fig.10 is a schematic diagram of an optional electronic device according to an embodiment of the present invention, such as Fig.10As shown, the electronic device includes one or more processors; a memory for storing one or more programs, which, when the one or more programs are executed by the one or more processors, enables the one or more processors to run the programs, wherein the programs are configured to execute the above-mentioned parameter adaptive control method of the virtual synchronous generator when running. When the processor executes the program, the following steps are implemented: based on the coupling value of the DC voltage change frequency band of the multi-terminal flexible DC system during operation, 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 a preset damping ratio, wherein the first optimization objective function is used to optimize the damping parameter; based on the differential mode frequency of 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 inertia parameter; 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 value of the virtual synchronous generator, wherein the target parameter value is used to adjust the virtual synchronous generator to achieve parameter adaptive control.

[0101] Optionally, the processor also implements the following steps when executing the program: calculating 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 unit matrix; constructing 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.

[0102] Optionally, when the processor executes the program, the following steps are also implemented: a first value is calculated based on the current damping coefficient, DC capacitor system and DC voltage value; a second value is calculated based on the current inertia coefficient, DC capacitor system, DC voltage value, DC voltage droop coefficient and line parameters; and the ratio of the first value to the second value is calculated to obtain the damping ratio of the output port.

[0103] Optionally, when the processor executes the program, the following steps are also implemented: obtaining the differential mode frequency of each converter station and obtaining the weights between the converter stations; and constructing a second optimization objective function based on the differential mode frequency of each converter station and the weights between the converter stations.

[0104] Optionally, when the processor executes the program, the following steps are also implemented: 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 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.

[0105] Optionally, when the processor executes the program, the following steps are also implemented: determining the constraints of the parameter adaptive function; using the gradient descent method to solve the parameter adaptive function based on the constraints to obtain the target parameter value of the virtual synchronous generator.

[0106] Optionally, when executing the program, the processor further implements the following steps: after obtaining the target parameter value of the virtual synchronous generator, 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.

[0107] The devices in this article can be servers, PCs, PADs, mobile phones, etc.

[0108] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0109] In the above embodiments of the present invention, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0110] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only schematic. For example, the division of the units can be a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.

[0111] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0112] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0113] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, magnetic disk or optical disk and other media that can store program codes.

[0114] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A parameter adaptive control method for a virtual synchronous generator, characterized in that: Applied to multi-terminal flexible DC systems, including: According to the coupling value of the DC voltage variation frequency band of the multi-terminal flexible DC system during operation, 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 according to the DC voltage droop coefficient, and a first optimization objective function is constructed according to the damping ratio of the output port and a preset damping ratio, wherein the first optimization objective function is used to optimize the damping parameter; Constructing a second optimization objective function according to 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 inertia parameter; According to 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 value of the virtual synchronous generator, wherein the target parameter value is used to adjust the virtual synchronous generator to achieve parameter adaptive control.

2. The method according to claim 1, characterized in that According to the coupling value of the DC voltage variation frequency band of the multi-terminal flexible DC system during operation, an adaptive DC voltage droop coefficient function is constructed, including: The coupling value of the DC voltage change frequency band is calculated 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 unit matrix; The adaptive DC voltage droop coefficient function is constructed according to 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.

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 according to the DC voltage droop coefficient, including: Calculate a first value according to the current damping coefficient, the DC capacitance system and the DC voltage value; Calculate a second value according to the current inertia coefficient, the DC capacitor system, the DC voltage value, the DC voltage droop coefficient and line parameters; The ratio of the first value to the second value is calculated to obtain the damping ratio of the output port.

4. The method according to claim 1, characterized in that: According to the differential mode frequencies of the multiple converter stations of the multi-terminal flexible DC system, a second optimization objective function is constructed, including: Obtaining the differential mode frequency of each converter station, and obtaining the weights between the converter stations; The second optimization objective function is constructed according to 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: According to 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: Determining a dynamic output function of the multi-terminal flexible DC system according to a small signal model of the multi-terminal flexible DC system; Obtaining a weighted coefficient matrix corresponding to the multi-terminal flexible DC system; The parameter adaptive function is constructed 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 second optimization objective function.

6. The method according to claim 1, characterized in that Solving the parameter adaptive function to obtain the target parameter value of the virtual synchronous generator includes: Determining constraints of the parameter adaptive function; The parameter adaptive function is solved based on the constraint conditions using a gradient descent method to obtain a target parameter value of the virtual synchronous generator.

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

8. A parameter adaptive control device for a virtual synchronous generator, characterized in that: Applied to multi-terminal flexible DC systems, including: A first processing module is used to construct an adaptive DC voltage droop coefficient function according to a coupling value of a DC voltage variation frequency band of the 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 the damping ratio of the 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 the damping parameter; A third processing module, configured to construct a second optimization objective function according to the differential mode frequencies of the plurality of converter stations of the multi-terminal flexible DC system, wherein the second optimization objective function is used to optimize the inertia parameter; The first determination module is used to construct a parameter adaptive function according to 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 a target parameter value of the virtual synchronous generator, wherein the target parameter value is 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 described in any one of claims 1 to 7 when running.

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 the one or more processors, enables the one or more processors to run the programs, wherein the program is configured to execute the parameter adaptive control method of the virtual synchronous generator described in any one of claims 1 to 7 when running.

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