Method, device and equipment for determining SVG control parameters, and readable storage medium

Abstract

The application discloses a method, device and equipment for determining SVG control parameters and a readable storage medium. The method comprises the following steps: setting a key operation condition of a new energy grid-connected system; determining a closed-loop transfer function matrix of the new energy grid-connected system according to a control structure of the new energy grid-connected system and in combination with an H-infinity control matrix of an SVG in the new energy grid-connected system; and determining SVG control parameters under the key operation condition based on the closed-loop transfer function matrix. The application determines the key operation condition of the new energy grid-connected system, determines the closed-loop transfer function matrix based on the H-infinity control matrix, and determines the SVG control parameters under the key operation condition. The new energy grid-connected system is controlled by using the SVG control parameters, the stability of the new energy grid-connected system containing the SVG can be improved, and better small interference robustness is achieved.

Description

Technical Field

[0001] This application relates to the field of power grid control, and more specifically, to a method, apparatus, device, and readable storage medium for determining SVG control parameters. Background Technology

[0002] With the development of new energy power generation technologies, the proportion of new energy equipment such as photovoltaic and wind power in the power grid is gradually increasing. Currently, new energy equipment mainly uses grid-connected converters synchronized with phase-locked loops as the grid interface. However, grid-connected converters provide weak voltage support to the power grid. Under the background of high proportion of new energy, the low short-circuit ratio and weak grid characteristics of the power grid become prominent, leading to a gradual increase in the interaction between new energy equipment and the power grid, which easily causes broadband oscillation problems. On the other hand, a certain proportion of static var generators (SVG) are generally equipped in new energy power plants to maintain voltage stability. However, existing studies have shown that SVG interacts with new energy equipment, and in severe cases, it can even worsen the broadband oscillation problem caused by new energy equipment.

[0003] To suppress oscillations caused by renewable energy equipment, numerous research findings on improved control strategy design have been developed, broadly categorized into two types: improved control of renewable energy equipment and improved control of additional equipment. In practice, manufacturers typically encapsulate the internal control structure of renewable energy equipment for commercial confidentiality reasons. Therefore, grid operators generally find it difficult to adjust the internal control parameters or improve the control structure of renewable energy equipment during actual operation. This limits the practical application of the approach of suppressing system oscillations based on improved renewable energy equipment control. In contrast, SVG (Static Var Generator) is a "white-box" model, making improved control design for SVG more convenient. For example, impedance reconstruction was performed on the control part of the SVG in a wind farm, and a sequence impedance model of a direct-drive wind farm containing the improved SVG was established. The positive impact of the proposed method on system stability was verified by comparing the impedance characteristics of the system before and after impedance reconstruction. However, the positive and negative characteristics of the system impedance in this model are not directly related to system stability. Furthermore, most of the above studies only consider a single operating scenario, making them difficult to apply to scenarios with changing operating conditions. Under extreme operating conditions, the proposed control strategies may fail.

[0004] Based on this, this application proposes a scheme for determining SVG control parameters to adapt to the existing situation, determine SVG control parameters, and realize the control of the new energy grid-connected system. Summary of the Invention

[0005] In view of this, this application provides a method, apparatus, device, and readable storage medium for determining SVG control parameters. By determining the key operating conditions of the new energy grid-connected system, determining the closed-loop transfer function matrix based on the H∞ control matrix, and determining the SVG control parameters under the key operating conditions, the new energy grid-connected system can be operated and controlled using the SVG control parameters, which can improve the stability of the new energy grid-connected system containing SVG and has better robustness against small disturbances.

[0006] A method for determining SVG control parameters, comprising:

[0007] The key operating conditions of the new energy grid-connected system are set, including the operating conditions of the new energy grid-connected system and the range of reactive current variation of the SVG output in the new energy grid-connected system;

[0008] Based on the control structure of the new energy grid-connected system and in conjunction with the H∞ control matrix of the SVG in the new energy grid-connected system, the closed-loop transfer function matrix of the new energy grid-connected system is determined.

[0009] Based on the closed-loop transfer function matrix, the SVG control parameters under the key operating conditions are determined.

[0010] Preferably, based on the control structure of the new energy grid-connected system and in conjunction with the H∞ control matrix of the SVG in the new energy grid-connected system, the closed-loop transfer function matrix of the new energy grid-connected system is determined, including:

[0011] Based on the control structure of the new energy grid-connected system, determine the open-loop state parameter matrix of the new energy grid-connected system;

[0012] Based on the open-loop state parameter matrix and the H∞ control matrix of the SVG in the new energy grid-connected system, the closed-loop transfer function matrix of the new energy grid-connected system is generated.

[0013] Preferably, in offline mode, based on the closed-loop transfer function matrix, the SVG control parameters under the key operating conditions are determined, including:

[0014] The key operating conditions are divided into several sub-operating intervals, and the several sub-operating intervals are different from each other and do not overlap.

[0015] The optimization solution is obtained by minimizing the H∞ control matrix and maximizing the infinity norm of the closed-loop transfer function matrix in each sub-operation interval, and then combined as the SVG control parameters for the key operating conditions.

[0016] Preferably, in the online state, based on the closed-loop transfer function matrix, the SVG control parameters under the key operating conditions are determined, including:

[0017] Obtain the real-time output reactive current of the SVG;

[0018] The SVG control parameters under the key operating conditions are obtained by optimizing the solution by minimizing the H∞ control matrix and maximizing the infinite norm of the closed-loop transfer function matrix under the real-time output reactive current.

[0019] Preferably, the H∞ control matrix of the SVG in the new energy grid-connected system is represented as:

[0020]

[0021] y = [U sq ,x1,(U s -1), x2] T

[0022]

[0023] Where K is the H∞ control matrix of the SVG, U sq Let x1 be the q-axis component of the SVG terminal voltage, and let x1 be U sq The integral, U s x2 is the terminal voltage amplitude of the SVG, and x2 is (U s The integral of -1), ω plls It is the frequency output of the phase-locked loop (PLL). This is the q-axis current reference value for the SVG, k acps and k acis These are the proportional and integral coefficients of the outer loop of the AC voltage, k pllps and k pllis These are the proportional and integral coefficients of the phase-locked loop, respectively.

[0024] Preferably, the closed-loop transfer function matrix of the new energy grid-connected system includes:

[0025] δ=C(sI-(A+BKC)) -1 B

[0026]

[0027] Where δ is the closed-loop transfer function matrix, A, B, and C are the open-loop state parameter matrices of the new energy grid-connected system, x, y, and u are the state vector, algebraic vector, and input vector, respectively, K is the H∞ control matrix of the SVG, and s is the transfer function.

[0028] An apparatus for determining SVG control parameters, comprising:

[0029] The key operating condition unit is used to set the key operating conditions of the new energy grid-connected system. The key operating conditions include the operating conditions of the new energy grid-connected system and the output reactive current variation range of the SVG in the new energy grid-connected system.

[0030] The matrix determination unit is used to determine the closed-loop transfer function matrix of the new energy grid-connected system based on the control structure of the new energy grid-connected system and in combination with the H∞ control matrix of the SVG in the new energy grid-connected system.

[0031] The control parameter unit is used to determine the SVG control parameters under the key operating conditions based on the closed-loop transfer function matrix.

[0032] Preferably, the matrix determining unit includes:

[0033] An open-loop matrix unit is used to determine the open-loop state parameter matrix of the new energy grid-connected system based on the control structure of the new energy grid-connected system.

[0034] The closed-loop matrix unit is used to generate the closed-loop transfer function matrix of the new energy grid-connected system based on the open-loop state parameter matrix and the H∞ control matrix of the SVG in the new energy grid-connected system.

[0035] A device for determining SVG control parameters, comprising a memory and a processor;

[0036] The memory is used to store programs;

[0037] The processor is used to execute the program to implement the various steps of the method for determining SVG control parameters as described above.

[0038] A readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method for determining SVG control parameters as described above.

[0039] As can be seen from the above technical solutions, the present application provides a method, apparatus, device, and readable storage medium for determining SVG control parameters. First, key operating conditions of the new energy grid-connected system are established. These key operating conditions include the operating conditions of the new energy grid-connected system and the reactive current variation range of the SVG output in the system. These key operating conditions are defined based on the influence of SVG on the system's small-disturbance stability under complex operating conditions, resulting in the operating condition with the worst small-disturbance stability. Then, according to the control structure of the new energy grid-connected system and combined with the H∞ control matrix of the SVG in the system, the closed-loop transfer function matrix of the new energy grid-connected system is determined. That is, based on H∞ control theory, the robust design problem of SVG control parameters in a new energy grid-connected system containing SVG under key operating conditions can be transformed into an optimization problem. Finally, based on the closed-loop transfer function matrix, the SVG control parameters under the key operating conditions are determined. Using the SVG control parameters to control the operation of the new energy grid-connected system can improve the stability of the new energy grid-connected system containing SVG. Meanwhile, this application can adaptively adjust its control parameters according to the changes in the reactive current of the SVG in the new energy grid-connected system, so that the new energy grid-connected system has better robustness against small disturbances. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0041] Figure 1 This is a flowchart illustrating a method for determining SVG control parameters disclosed in an embodiment of this application;

[0042] Figure 2 This is a schematic diagram of the processing logic of a method for determining SVG control parameters disclosed in an embodiment of this application;

[0043] Figure 3 This is a schematic diagram of the structure of a single renewable energy grid-connected system for SVG disclosed in an embodiment of this application;

[0044] Figure 4 This is a structural block diagram of an SVG control parameter determination device disclosed in an embodiment of this application;

[0045] Figure 5 This is a hardware structure block diagram of an SVG control parameter determination device disclosed in an embodiment of this application. Detailed Implementation

[0046] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0047] The following section introduces the solution proposed in this application. The technical solution is as follows, and details are provided below.

[0048] This application can be used in a wide variety of general-purpose or special-purpose computing environments or configurations. For example: personal computers, server computers, multiprocessor devices, distributed computing environments including any of the above devices or equipment, etc.

[0049] This application provides a method for determining SVG control parameters. This method can be applied to various new energy grid-connected systems or new energy power station control platforms, as well as to various computer terminals or smart terminals. The executing entity can be the processor or server of the computer terminal or smart terminal.

[0050] The following section introduces the solution proposed in this application. The technical solution is as follows, and details are provided below.

[0051] Figure 1 This is a flowchart illustrating a method for determining SVG control parameters disclosed in an embodiment of this application.

[0052] Figure 2 This is a schematic diagram of the processing logic of a method for determining SVG control parameters disclosed in an embodiment of this application.

[0053] like Figure 1 and Figure 2 As shown, the method may include:

[0054] Step S1: Set the key operating conditions for the new energy grid-connected system.

[0055] Specifically, the key operating conditions include the operating conditions of the renewable energy grid-connected system and the range of reactive current variation of the SVG output in the renewable energy grid-connected system. The key operating conditions are defined based on the influence of SVG on the system's small-disturbance stability under complex operating conditions, resulting in the operating condition with the worst small-disturbance stability. Under the premise that SVG always improves system stability, as the active power output P of the renewable energy equipment... e As the magnitude decreases, the stability of the system under small disturbances always improves.

[0056] The setting of critical operating conditions needs to conform to the actual operating conditions and application requirements of the renewable energy grid-connected system. Generally, the critical operating conditions are set when the renewable energy grid-connected system operates under rated conditions, and the reactive current I of the SVG in the renewable energy grid-connected system is... qs The range of variation is [-1, 1], which is the critical operating condition, i.e. the operating condition where the system has the worst stability under small disturbances.

[0057] Step S2: Based on the control structure of the new energy grid-connected system and in conjunction with the H∞ control matrix of the SVG in the new energy grid-connected system, determine the closed-loop transfer function matrix of the new energy grid-connected system.

[0058] Specifically, based on the control structure of the new energy grid-connected system and combined with the H∞ control matrix of the SVG in the new energy grid-connected system, this application determines the closed-loop transfer function matrix of the new energy grid-connected system. That is, based on H∞ control theory, the robust design problem of SVG control parameters in a new energy grid-connected system containing SVG under key operating conditions can be transformed into an optimization problem. Step S2 can be divided into the following two steps:

[0059] ① Determine the open-loop state parameter matrix of the new energy grid-connected system based on the control structure of the new energy grid-connected system.

[0060]

[0061] In this system, A, B, and C are open-loop state parameter matrices of the renewable energy grid-connected system, and x, y, and u are the state vector, algebraic vector, and input vector, respectively. When the renewable energy equipment is a "black box" model, the specific forms of the open-loop state parameter matrices A, B, and C can be identified.

[0062] ② Based on the open-loop state parameter matrix and the H∞ control matrix of the SVG in the new energy grid-connected system, generate the closed-loop transfer function matrix of the new energy grid-connected system.

[0063] The closed-loop transfer function matrix of the new energy grid-connected system includes:

[0064] δ=C(sI-(A+BKC)) -1 B

[0065] Where δ is the closed-loop transfer function matrix, A, B, and C are the open-loop state parameter matrices of the new energy grid-connected system, K is the H∞ control matrix of the SVG, and s is the transfer function.

[0066] To simplify the control design, without changing the original control structure of the SVG, the K matrix is ​​selected as the static gain matrix, and the proportional-integral (PI) parameters in the AC voltage control loop and phase-locked loop (PLL) are selected as elements in the controller K.

[0067] The H∞ control matrix of the SVG in the new energy grid-connected system is expressed as:

[0068]

[0069]

[0070] Where K is the H∞ control matrix of the SVG, K can be the dynamic transfer function matrix related to "s" or the static gain matrix, U sq Let x1 be the q-axis component of the SVG terminal voltage, and let x1 be U sq The integral, U s x2 is the terminal voltage amplitude of the SVG, and x2 is (U s The integral of -1), ω plls It is the frequency output of the phase-locked loop (PLL). This is the q-axis current reference value for the SVG, k acps and k acis These are the proportional and integral coefficients of the outer loop of the AC voltage, k pllps and k pllis These are the proportional and integral coefficients of the phase-locked loop, respectively.

[0071] Step S3: Based on the closed-loop transfer function matrix, determine the SVG control parameters under the key operating conditions.

[0072] Specifically, based on the control concept of H∞, the robust design problem of SVG control parameters in a new energy grid-connected system containing SVG under key operating conditions can be described as a mini-maximum optimization problem, namely:

[0073]

[0074] Among them, ||.|| ∞ It is an infinite norm, C(sI-(A+BKC)). -1 B is the closed-loop transfer function matrix of the new energy grid-connected system.

[0075] As can be seen from the above technical solutions, the present application provides a method, apparatus, device, and readable storage medium for determining SVG control parameters. First, key operating conditions of the new energy grid-connected system are established. These key operating conditions include the operating conditions of the new energy grid-connected system and the reactive current variation range of the SVG output in the system. These key operating conditions are defined based on the influence of SVG on the system's small-disturbance stability under complex operating conditions, resulting in the operating condition with the worst small-disturbance stability. Then, according to the control structure of the new energy grid-connected system and combined with the H∞ control matrix of the SVG in the system, the closed-loop transfer function matrix of the new energy grid-connected system is determined. That is, based on H∞ control theory, the robust design problem of SVG control parameters in a new energy grid-connected system containing SVG under key operating conditions can be transformed into an optimization problem. Finally, based on the closed-loop transfer function matrix, the SVG control parameters under the key operating conditions are determined. Using the SVG control parameters to control the operation of the new energy grid-connected system can improve the stability of the new energy grid-connected system containing SVG. Meanwhile, this application can adaptively adjust its control parameters according to the changes in the reactive current of the SVG in the new energy grid-connected system, so that the new energy grid-connected system has better robustness against small disturbances.

[0076] In some embodiments of this application, the process of determining the SVG control parameters under the key operating conditions based on the closed-loop transfer function matrix in step S3 is described. The process of determining the SVG control parameters can be divided into the following two cases:

[0077] The first method involves determining the SVG control parameters for the key operating conditions offline, based on the closed-loop transfer function matrix, including:

[0078] ① Divide the key operating conditions into several sub-operating intervals, wherein the several sub-operating intervals are different from each other and do not overlap.

[0079] ② The optimization solution is performed by minimizing the H∞ control matrix and maximizing the infinite norm of the closed-loop transfer function matrix in each sub-operation interval to obtain the SVG control parameters in each sub-operation interval, and then combined as the SVG control parameters in the key operating condition.

[0080] Specifically, considering the reactive current I of the SVG corresponding to key operating conditions in practical applications... qs The range of variation is [-1, 1]. If this range is too large, the optimization problem may become unsolvable. Therefore, the key operating conditions can be divided into several sub-operating ranges.

[0081] For example, P e =1p.u.,I qsIn the ranges [-1, -1+2 / m), [-1+2 / m, -1+4 / m), ..., (-1+2*(m-1) / m, 1], the corresponding SVG controller K is solved for each sub-running interval. i (i = 1, ..., m).

[0082] In offline mode, for each of the m sub-operation periods after the key operating conditions are divided, the optimization problem is solved to obtain the control parameters Ki of the m controllers, which are then combined as the SVG control parameters under the key operating conditions.

[0083] The second method involves determining the SVG control parameters under the key operating conditions based on the closed-loop transfer function matrix while in an online state, including:

[0084] ① Obtain the real-time output reactive current of the SVG.

[0085] ② The SVG control parameters under the key operating conditions are obtained by optimizing the solution by minimizing the H∞ control matrix and maximizing the infinite norm of the closed-loop transfer function matrix under the real-time output reactive current.

[0086] Specifically, during the online process, based on the real-time reactive current output of the SVG, the appropriate controller K can be selected. i The control parameters of the SVG are then updated. It's important to note that as the value of m increases, the SVG's control effect on improving the system's stability under small disturbances improves. However, an excessively large m may lead to frequent switching of SVG control parameters, excessively high communication requirements, and significant economic costs. Therefore, a trade-off between control effect and economy needs to be considered when selecting the value of m. Experiments have shown that for new energy grid-connected systems containing SVG, selecting four equal parts is generally sufficient to meet the requirements.

[0087] The following example illustrates this application.

[0088] Figure 3 This is a schematic diagram of the structure of a single renewable energy grid-connected system for SVG disclosed in an embodiment of this application.

[0089] A single renewable energy grid-connected system with SVG was built in Matlab / Simulink software. The renewable energy equipment and SVG capacity were set to 1 p.u. and 0.4 p.u., respectively. The line inductances L1 and L... g The values ​​are 0.06 pu and 0.6 pu, respectively. The control parameters for the new energy equipment and SVG are shown in Tables 1 and 2. The new energy equipment uses constant DC voltage control, while the SVG equipment uses constant AC voltage control.

[0090] Table 1 Parameter values ​​of new energy equipment

[0091] Filter inductance L f / pu]] 0.05 Filter capacitor C f / pu]] 0.05 Direct current voltage outer loop H dc (s) proportional, integral parameters 0.5,5 <![CDATA[Proportional and integral parameters of the inner current loop H i (s)]]> 0.3,10 <![CDATA[Phase-locked loop H PLL (s) proportional and integral parameters]]> 3,3080 Voltage feedforward GFF(s) filter time constant 0.002 <![CDATA[DC voltage reference value U dcref / pu]]> 1 <![CDATA[Reactive current command I qref / pu]]> 0

[0092] Table 2 Parameter values ​​for SVG devices

[0093] <![CDATA[Filter inductor L fs / pu]]> 0.1 <![CDATA[DC voltage outer loop H dcs (s) proportional and integral parameters]]> 0.6,8 <![CDATA[Proportional and integral parameters of AC voltage outer loop H acs (s)]]> 0.6,8 <![CDATA[Proportional and integral parameters of the inner current loop H is (s)]]><![CDATA[]]>[['end']] 0.6,12 <![CDATA[Phase-locked loop H PLLs (s) proportional and integral parameters]]> 40,2400 <![CDATA[Voltage feedforward G FFs (s) filtering time constant]]> 0.01 <![CDATA[DC voltage reference value U dcrefs / pu]]> 1

[0094] Taking the use of constant DC voltage control in new energy equipment and constant AC voltage control in SVG as examples, consider the following three cases:

[0095] Scenario 1: Divide the critical operating conditions into 4 intervals, namely P e =1p.u., reactive current I of SVG qs The range of variation is divided into four equal parts: [-1, -0.5), [-0.5, 0), [0, 0.5), [0.5, 1];

[0096] Scenario 2: Divide the critical operating conditions into two intervals, that is, divide the SVG into two equal parts: [-1,0), [0,1];

[0097] Case 3: Divide the critical operating conditions into one interval, i.e., the SVG does not divide the interval: [-1,1].

[0098] For the three cases mentioned above, the optimization problem was solved using the Matlab solver. The specific results are shown in Tables 3 and 4, respectively, where AVC represents AC voltage control.

[0099] Table 3 shows the SVG control parameters for the following cases.

[0100] PLL 20.1+4345.0 / s 5.0+837.3 / s 5.0+100 / s 15.2+10000 / s AVC 4.13+5 / s 4.39+5 / s 4.42+5 / s 4.04+5 / s

[0101] Table 4 SVG control parameters for cases two and three

[0102]

[0103] The present application describes the apparatus for determining SVG control parameters provided in the embodiments. The apparatus for determining SVG control parameters described below and the method for determining SVG control parameters described above can be referred to in correspondence.

[0104] See Figure 4 , Figure 4 This is a structural block diagram of an SVG control parameter determination device disclosed in an embodiment of this application.

[0105] like Figure 4 As shown, the device for determining the SVG control parameters may include:

[0106] The key operating condition unit 110 is used to set the key operating conditions of the new energy grid-connected system. The key operating conditions include the operating conditions of the new energy grid-connected system and the output reactive current variation range of the SVG in the new energy grid-connected system.

[0107] The matrix determination unit 120 is used to determine the closed-loop transfer function matrix of the new energy grid-connected system based on the control structure of the new energy grid-connected system and in combination with the H∞ control matrix of the SVG in the new energy grid-connected system.

[0108] The control parameter unit 130 is used to determine the SVG control parameters under the key operating conditions based on the closed-loop transfer function matrix.

[0109] As can be seen from the above technical solutions, the present application provides a method, apparatus, device, and readable storage medium for determining SVG control parameters. First, key operating conditions of the new energy grid-connected system are established. These key operating conditions include the operating conditions of the new energy grid-connected system and the reactive current variation range of the SVG output in the system. These key operating conditions are defined based on the influence of SVG on the system's small-disturbance stability under complex operating conditions, resulting in the operating condition with the worst small-disturbance stability. Then, according to the control structure of the new energy grid-connected system and combined with the H∞ control matrix of the SVG in the system, the closed-loop transfer function matrix of the new energy grid-connected system is determined. That is, based on H∞ control theory, the robust design problem of SVG control parameters in a new energy grid-connected system containing SVG under key operating conditions can be transformed into an optimization problem. Finally, based on the closed-loop transfer function matrix, the SVG control parameters under the key operating conditions are determined. Using the SVG control parameters to control the operation of the new energy grid-connected system can improve the stability of the new energy grid-connected system containing SVG. Meanwhile, this application can adaptively adjust its control parameters according to the changes in the reactive current of the SVG in the new energy grid-connected system, so that the new energy grid-connected system has better robustness against small disturbances.

[0110] Optionally, the matrix determining unit may include:

[0111] An open-loop matrix unit is used to determine the open-loop state parameter matrix of the new energy grid-connected system based on the control structure of the new energy grid-connected system.

[0112] The closed-loop matrix unit is used to generate the closed-loop transfer function matrix of the new energy grid-connected system based on the open-loop state parameter matrix and the H∞ control matrix of the SVG in the new energy grid-connected system.

[0113] Optionally, the control parameter unit may include an offline processing unit and an online processing unit;

[0114] The offline processing unit, while in an offline state, determines the SVG control parameters under the key operating conditions based on the closed-loop transfer function matrix. This process may include:

[0115] The key operating conditions are divided into several sub-operating intervals, and the several sub-operating intervals are different from each other and do not overlap.

[0116] The optimization solution is obtained by minimizing the H∞ control matrix and maximizing the infinite norm of the closed-loop transfer function matrix in each sub-operation interval, and then combined as the SVG control parameters in the key operating condition.

[0117] The process by which the online processing unit, while in an online state, determines the SVG control parameters under the key operating conditions based on the closed-loop transfer function matrix may include:

[0118] Obtain the real-time output reactive current of the SVG;

[0119] The SVG control parameters under the key operating conditions are obtained by optimizing the solution by minimizing the H∞ control matrix and maximizing the infinite norm of the closed-loop transfer function matrix under the real-time output reactive current.

[0120] Optionally, the H∞ control matrix of the SVG in the new energy grid-connected system is represented as:

[0121]

[0122] y = [U sq ,x1,(U s -1), x2] T

[0123]

[0124] Where K is the H∞ control matrix of the SVG, U sq Let x1 be the q-axis component of the SVG terminal voltage, and x1 be U sq The integral, U s x2 is the terminal voltage amplitude of the SVG, and x2 is (U s The integral of -1), ω plls It is the frequency output of the phase-locked loop (PLL). This is the q-axis current reference value for the SVG, k acps and k acis These are the proportional and integral coefficients of the outer loop of the AC voltage, k pllps and k pllis These are the proportional and integral coefficients of the phase-locked loop, respectively.

[0125] Optionally, the closed-loop transfer function matrix of the new energy grid-connected system includes:

[0126] δ=C(sI-(A+BKC)) -1 B

[0127]

[0128] Where δ is the closed-loop transfer function matrix, A, B, and C are the open-loop state parameter matrices of the new energy grid-connected system, x, y, and u are the state vector, algebraic vector, and input vector, respectively, K is the H∞ control matrix of the SVG, and s is the transfer function.

[0129] The SVG control parameter determination device provided in this application embodiment can be applied to SVG control parameter determination equipment. Figure 5 The hardware structure of the device may include: at least one processor 1, at least one communication interface 2, at least one memory 3, and at least one communication bus 4;

[0130] In this embodiment of the application, the number of processor 1, communication interface 2, memory 3, and communication bus 4 is at least one, and processor 1, communication interface 2, and memory 3 communicate with each other through communication bus 4;

[0131] Processor 1 may be a central processing unit (CPU), an application-specific integrated circuit (ASIC), or one or more integrated circuits configured to implement embodiments of the present invention.

[0132] Memory 3 may include high-speed RAM, and may also include non-volatile memory, such as at least one disk storage device;

[0133] The memory stores a program, which the processor can call. The program is used for:

[0134] The key operating conditions of the new energy grid-connected system are set, including the operating conditions of the new energy grid-connected system and the range of reactive current variation of the SVG output in the new energy grid-connected system;

[0135] Based on the control structure of the new energy grid-connected system and in conjunction with the H∞ control matrix of the SVG in the new energy grid-connected system, the closed-loop transfer function matrix of the new energy grid-connected system is determined.

[0136] Based on the closed-loop transfer function matrix, the SVG control parameters under the key operating conditions are determined.

[0137] Optionally, the refined and extended functions of the program can be referred to the above description.

[0138] This application embodiment also provides a readable storage medium that can store a program suitable for execution by a processor, the program being used for:

[0139] The key operating conditions of the new energy grid-connected system are set, including the operating conditions of the new energy grid-connected system and the range of reactive current variation of the SVG output in the new energy grid-connected system;

[0140] Based on the control structure of the new energy grid-connected system and in conjunction with the H∞ control matrix of the SVG in the new energy grid-connected system, the closed-loop transfer function matrix of the new energy grid-connected system is determined.

[0141] Based on the closed-loop transfer function matrix, the SVG control parameters under the key operating conditions are determined.

[0142] Optionally, the refined and extended functions of the program can be referred to the above description.

[0143] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0144] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0145] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for determining SVG control parameters, characterized in that, include: The key operating conditions of the new energy grid-connected system are set, including the operating conditions of the new energy grid-connected system and the range of reactive current variation of the SVG output in the new energy grid-connected system; Based on the control structure of the new energy grid-connected system and in conjunction with the H∞ control matrix of the SVG in the new energy grid-connected system, the closed-loop transfer function matrix of the new energy grid-connected system is determined. In offline mode, based on the closed-loop transfer function matrix, the SVG control parameters for the key operating conditions are determined, including: The key operating conditions are divided into several sub-operating intervals, and the several sub-operating intervals are different from each other and do not overlap. The optimization solution is obtained by minimizing the H∞ control matrix and maximizing the infinite norm of the closed-loop transfer function matrix in each sub-operation interval, and then combined as the SVG control parameters in the key operating condition. In the online state, based on the closed-loop transfer function matrix, the SVG control parameters under the key operating conditions are determined, including: Obtain the real-time output reactive current of the SVG; The SVG control parameters under the key operating conditions are obtained by optimizing the solution by minimizing the H∞ control matrix and maximizing the infinite norm of the closed-loop transfer function matrix under the real-time output reactive current. The H∞ control matrix of the SVG in the new energy grid-connected system is expressed as: y=[U sq ,x1,(U s -1), x2] T Where K is the H∞ control matrix of the SVG, U sq Let x1 be the q-axis component of the SVG terminal voltage, and let x1 be U sq The integral, U s x2 is the terminal voltage amplitude of the SVG, and x2 is (U s The integral of -1), It is the frequency output of the phase-locked loop (PLL). This is the q-axis current reference value for the SVG, k acps and k acis These are the proportional and integral coefficients of the outer loop of the AC voltage, k pllps and k pllis These are the proportional and integral coefficients of the phase-locked loop, respectively. The closed-loop transfer function matrix of the new energy grid-connected system includes: δ= Where δ is the closed-loop transfer function matrix, A, B, and C are the open-loop state parameter matrices of the new energy grid-connected system, x, y, and u are the state vector, algebraic vector, and input vector, respectively, K is the H∞ control matrix of the SVG, s is the transfer function, and I is the identity matrix.

2. The method according to claim 1, characterized in that, Based on the control structure of the new energy grid-connected system and in conjunction with the H∞ control matrix of the SVG in the new energy grid-connected system, the closed-loop transfer function matrix of the new energy grid-connected system is determined, including: Based on the control structure of the new energy grid-connected system, determine the open-loop state parameter matrix of the new energy grid-connected system; Based on the open-loop state parameter matrix and the H∞ control matrix of the SVG in the new energy grid-connected system, the closed-loop transfer function matrix of the new energy grid-connected system is generated.

3. A device for determining SVG control parameters, characterized in that, Implementing each step of the method for determining SVG control parameters as described in claim 1 or 2 includes: The key operating condition unit is used to set the key operating conditions of the new energy grid-connected system. The key operating conditions include the operating conditions of the new energy grid-connected system and the output reactive current variation range of the SVG in the new energy grid-connected system. The matrix determination unit is used to determine the closed-loop transfer function matrix of the new energy grid-connected system based on the control structure of the new energy grid-connected system and in combination with the H∞ control matrix of the SVG in the new energy grid-connected system. The control parameter unit is used to determine the SVG control parameters under the key operating conditions based on the closed-loop transfer function matrix.

4. The apparatus according to claim 3, characterized in that, The matrix determination unit includes: An open-loop matrix unit is used to determine the open-loop state parameter matrix of the new energy grid-connected system based on the control structure of the new energy grid-connected system. The closed-loop matrix unit is used to generate the closed-loop transfer function matrix of the new energy grid-connected system based on the open-loop state parameter matrix and the H∞ control matrix of the SVG in the new energy grid-connected system.

5. A device for determining SVG control parameters, characterized in that, Including memory and processor; The memory is used to store programs; The processor is configured to execute the program to implement the various steps of the method for determining SVG control parameters as described in claim 1 or 2.

6. A readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the various steps of the method for determining SVG control parameters as described in claim 1 or 2.

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