Remodeling control method and device for improving voltage support capability of grid-type SVG converter

Abstract

A remodeling control method and device for improving the voltage support capability of a grid-type SVG converter, the method comprising: obtaining the internal potential phase and internal potential amplitude of the SVG converter based on a virtual excitation control SVG converter model, based on the internal potential phase and internal potential amplitude, converting the SVG converter into a voltage source series impedance form as a simplified SVG converter model, obtaining adjustable parameters based on the simplified SVG converter model, and adjusting the adjustable parameters to improve the voltage support capability of the SVG converter. The method and device provided by the embodiments of the present invention can increase the rate at which the SVG converter outputs reactive power during transient periods, can improve the voltage support capability of the SVG converter, and improve the voltage strength of the power system.

Description

Technical Field

[0001] The present invention relates to the technical field of power systems, and in particular to a reshaping control method and device for improving the voltage support capability of a grid-type SVG converter. Background Art

[0002] In recent years, renewable energy power generation technology has been widely used, and static VAR generator (SVG) has been widely used in reactive power compensation of renewable energy power generation system with its flexible reactive power compensation capability and fast dynamic response. SVG converter is the interface between system and device, and its control mode plays a key role in the output characteristics of SVG. At present, there are SVG converters using direct current control. Direct current control can send out corresponding active power and reactive power according to the given current value, but it requires a phase-locked loop to obtain the actual phase of the power grid. The phase-locked loop may have stability problems during the transient process of the power grid, which is not conducive to the reliable operation of SVG. In addition, SVG using direct current control shows current source characteristics to the outside, and has limited support for the voltage of the power grid. Summary of the invention

[0003] In view of the shortcomings of the prior art, the present invention proposes a reshaping control method and device for improving the voltage supporting capability of a grid-type SVG converter, aiming to solve the problem of limited voltage supporting capability and weak effect of SVG converters using direct current control during voltage transients.

[0004] In the first aspect, an embodiment of the present invention provides a reshaping control method for improving the voltage supporting capability of a grid-type SVG converter, which is applied to a grid-type SVG converter. The reshaping control method includes: obtaining an internal potential phase and an internal potential amplitude of the SVG converter based on a virtual excitation control SVG converter model; based on the internal potential phase and the internal potential amplitude, converting the SVG converter into a voltage source series impedance as a simplified model of the SVG converter; based on the simplified SVG converter model, obtaining adjustable parameters; and adjusting the adjustable parameters to improve the voltage supporting capability of the SVG converter.

[0005] Further, the internal potential phase is as follows:

[0006] ;

[0007] in, ω 0 is the rated angular frequency, K p is the power synchronization coefficient, P ref is the power reference value, P e is the output power of the SVG converter, sis the Laplace operator, t For time;

[0008] The internal potential amplitude is as follows:

[0009] ;

[0010] in, K is the regulator gain, K v Select the factor for proportional-integral, T 1 and T 2 are the first voltage regulator time constant and the second voltage regulator time constant, respectively, U t * is the reference value of the AC voltage amplitude at the grid connection point, U t is the AC voltage amplitude at the grid connection point, T ’ d0 is the time constant of the virtual excitation winding.

[0011] Furthermore, based on the simplified SVG converter model, adjustable parameters are obtained, including: based on the simplified SVG converter model, obtaining the derivative of the reactive power of the simplified SVG converter model with respect to the AC voltage amplitude at the grid connection point; based on the derivative, obtaining adjustable parameters.

[0012] Furthermore, the derivative of the reactive power of the simplified model of the SVG converter to the AC voltage amplitude at the grid connection point is as follows:

[0013] ;

[0014] in, Q is the reactive power, U t is the AC voltage amplitude at the grid connection point, E is the internal potential amplitude, θ is the internal potential phase, x c For the reactance.

[0015] Furthermore, the adjustable parameters include: regulator gain K , virtual excitation winding time constant T ’ d0 , first voltage regulator time constant T 1 and the second voltage regulator time constant T 2 .

[0016] Furthermore, adjusting the adjustable parameters to improve the voltage support capability of the SVG converter includes: adjusting the adjustable parameters to increase the bandwidth of the virtual excitation control module, thereby improving the voltage support capability of the SVG converter.

[0017] In the second aspect, an embodiment of the present invention further provides a reshaping control device for improving the voltage supporting capability of a grid-type SVG converter, which is applied to a grid-type SVG converter. The reshaping control device includes: a first processing unit, which is used to obtain the internal potential phase and internal potential amplitude of the SVG converter based on the SVG converter model of virtual excitation control; a simplification unit, which is used to convert the SVG converter into a form of a voltage source series impedance based on the internal potential phase and the internal potential amplitude, as a simplified model of the SVG converter; a second processing unit, which is used to obtain adjustable parameters based on the simplified model of the SVG converter; and an adjustment unit, which is used to adjust the adjustable parameters to improve the voltage supporting capability of the SVG converter.

[0018] Further, the internal potential phase is as follows:

[0019] ;

[0020] in, ω 0 is the rated angular frequency, K p is the power synchronization coefficient, P ref is the power reference value, P e is the output power of the SVG converter, s is the Laplace operator, t For time;

[0021] The internal potential amplitude is as follows:

[0022] ;

[0023] in, K is the regulator gain, K v Select the factor for proportional-integral, T 1 and T 2 are the first voltage regulator time constant and the second voltage regulator time constant, respectively, U t * is the reference value of the AC voltage amplitude at the grid connection point, U t is the AC voltage amplitude at the grid connection point, T ’ d0is the time constant of the virtual excitation winding.

[0024] Furthermore, the second processing unit is also used to: obtain the derivative of the reactive power of the simplified SVG converter model with respect to the AC voltage amplitude at the grid connection point based on the simplified SVG converter model; and obtain an adjustable parameter based on the derivative.

[0025] Furthermore, the derivative of the reactive power of the simplified model of the SVG converter to the AC voltage amplitude at the grid connection point is as follows:

[0026] ;

[0027] in, Q is the reactive power, U t is the AC voltage amplitude at the grid connection point, E is the internal potential amplitude, θ is the internal potential phase, x c For the reactance.

[0028] Furthermore, the adjustable parameters include: regulator gain K , virtual excitation winding time constant T ’ d0 , first voltage regulator time constant T 1 and the second voltage regulator time constant T 2 .

[0029] Furthermore, the regulating unit is further used to: regulate the adjustable parameters to increase the bandwidth of the virtual excitation control module, thereby improving the voltage support capability of the SVG converter.

[0030] In a third aspect, an embodiment of the present invention further provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the reshaping control method provided in the above embodiments is implemented.

[0031] In a fourth aspect, an embodiment of the present invention further provides an electronic device, comprising: a processor; a memory for storing executable instructions of the processor; the processor is used to read the executable instructions from the memory and execute the instructions to implement the reshaping control method provided in the above embodiments.

[0032] The embodiments of the present invention provide a remodeling control method and device for improving the voltage support capability of a grid-type SVG converter. Based on a virtual excitation controlled SVG converter model, the internal potential phase and internal potential amplitude of the SVG converter are obtained. Based on the internal potential phase and internal potential amplitude, the SVG converter is equivalent to a voltage source in series with an impedance as a simplified SVG converter model. Based on the simplified SVG converter model, adjustable parameters are obtained, and the adjustable parameters are adjusted to improve the voltage support capability of the SVG converter. This can increase the rate at which the SVG converter outputs reactive power during transient periods, improve the voltage support capability of the SVG converter, and thereby improve the voltage strength of the power system. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 An exemplary flow chart of a remodeling control method for improving the voltage support capability of a grid-type SVG converter according to an embodiment of the present invention is shown;

[0034] Figure 2 A schematic structural diagram of a grid-type SVG converter model using virtual excitation control according to an embodiment of the present invention is shown;

[0035] Figure 3 A schematic diagram of the structure of a simplified model of an SVG converter according to an embodiment of the present invention is shown;

[0036] Figure 4 An exemplary flow chart of a controllable parameter optimization process based on a particle swarm algorithm according to an embodiment of the present invention is shown;

[0037] Figure 5 A simulation data diagram showing a comparison of the voltage support capability of a meshed SVG converter before and after the method for improving the voltage support capability of a meshed SVG converter is adopted according to an embodiment of the present invention;

[0038] Figure 6 A schematic structural diagram of a remodeling control device for improving the voltage support capability of a grid-type SVG converter according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0039] Now, exemplary embodiments of the present invention are described with reference to the accompanying drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to disclose the present invention in detail and completely and to fully convey the scope of the present invention to those skilled in the art. The terms used in the exemplary embodiments shown in the accompanying drawings are not intended to limit the present invention. In the accompanying drawings, the same units / elements are marked with the same reference numerals.

[0040] Unless otherwise specified, the terms (including technical terms) used herein have the commonly understood meanings to those skilled in the art. In addition, it is understood that the terms defined in commonly used dictionaries should be understood to have the same meanings as those in the context of the relevant fields, and should not be understood as idealized or overly formal meanings.

[0041] Figure 1 An exemplary flow chart of a remodeling control method for improving the voltage support capability of a grid-type SVG converter according to an embodiment of the present invention is shown.

[0042] like Figure 1 As shown, the reshaping control method is applied to a grid-type SVG converter, including:

[0043] Step S101: based on the SVG converter model of virtual excitation control, the internal potential phase and internal potential amplitude of the SVG converter are obtained.

[0044] Furthermore, the internal potential phase is as follows:

[0045] ;

[0046] in, ω 0 is the rated angular frequency, K p is the power synchronization coefficient, P ref is the power reference value, P e is the output power of the SVG converter, s is the Laplace operator, t For time;

[0047] The internal potential amplitude is as follows:

[0048] ;

[0049] in, K is the regulator gain, K v Select the factor for proportional-integral, T 1 and T 2 are the first voltage regulator time constant and the second voltage regulator time constant, respectively, U t * is the reference value of the AC voltage amplitude at the grid connection point, U t is the AC voltage amplitude at the grid connection point, T ’ d0 is the time constant of the virtual excitation winding.

[0050] Specifically, during grid voltage transients, the dynamic characteristics of the SVG are mainly determined by the interface converter dynamics. Figure 2 FIG. 4 shows a schematic diagram of a structure of a grid-type SVG converter model using virtual excitation control according to an embodiment of the present invention. Figure 2 As shown in the figure, the SVG converter model using virtual excitation control mainly includes:

[0051] 1) Synchronous control module, which adopts power synchronous control to realize synchronous grid connection of converter and generate potential phase in converter , the specific expression is:

[0052] (1)

[0053] In the formula, ω 0 is the rated angular frequency, K p is the power synchronization coefficient, P ref is the power reference value, P e is the output power of the SVG converter, s is the Laplace operator, t For time;

[0054] Furthermore, the power reference value P ref , obtained from the output of the DC voltage controller, can be expressed as:

[0055] ;

[0056] in, U dc is a DC voltage signal, U dcref is the DC voltage reference value, k pv is the proportional coefficient of DC voltage control, k iv is the integral coefficient of the DC voltage controller;

[0057] 2) Internal potential control module, used to generate the internal potential amplitude of the converter E , using virtual excitation control, the specific expression is:

[0058] (2)

[0059] In the formula, K is the regulator gain, K v Select the factor for proportional-integral,T 1 and T 2 are the first voltage regulator time constant and the second voltage regulator time constant, respectively, U t * is the reference value of the AC voltage amplitude at the grid connection point, U t is the AC voltage amplitude at the grid connection point, T ’ d0 is the time constant of the virtual excitation winding.

[0060] also, Figure 2 middle V max and V min They are the maximum and minimum output voltages of the virtual excitation control module respectively.

[0061] Step S102: Based on the internal potential phase and the internal potential amplitude, the SVG converter is equivalent to a voltage source in series with an impedance to serve as a simplified model of the SVG converter.

[0062] Specifically, Figure 3 The structure diagram of the simplified model of the SVG converter according to an embodiment of the present invention is shown. The dynamic characteristics of the grid-type SVG converter described by equations (1) and (2) can be equivalent to a voltage source in series with an impedance, such as Figure 3 shown.

[0063] Step S103: obtaining adjustable parameters based on the simplified model of the SVG converter.

[0064] Further, step S103 includes:

[0065] Based on the simplified model of SVG converter, the derivative of the reactive power of the simplified model of SVG converter to the AC voltage amplitude of the grid connection point is obtained;

[0066] Based on the derivatives, adjustable parameters are obtained.

[0067] Furthermore, the derivative of the reactive power of the simplified SVG converter model with respect to the AC voltage amplitude at the grid connection point is as follows:

[0068] ;

[0069] in, Q is the reactive power, U t is the AC voltage amplitude at the grid connection point, E is the internal potential amplitude, θ is the internal potential phase,x c For the reactance.

[0070] Furthermore, the adjustable parameters include: regulator gain K , virtual excitation winding time constant T ’ d0 , first voltage regulator time constant T 1 and the second voltage regulator time constant T 2 .

[0071] Specifically, Figure 3 The simplified model of SVG converter is shown in the figure below. The relevant variables are as follows:

[0072] 1) is the potential vector in the grid-connected SVG converter based on virtual excitation control, , E is the magnitude of the internal potential, Output phase for synchronous control module;

[0073] 2) is the voltage vector at the grid connection point of the SVG network, , U t is the voltage amplitude at the grid connection point, is the voltage phase size at the grid connection point;

[0074] 3) x c To build the SVG and connect the grid point to the reactance, including the SVG converter bridge arm reactance, filter reactance, transformer equivalent reactance, etc. x c is the sum of the above-mentioned reactances;

[0075] is the output current vector of the grid-type SVG converter, with the grid-connected point voltage as the reference voltage ( middle =0), the output current expression of the grid-type SVG converter is:

[0076] (3)

[0077] In the formula, the first term on the right side of the equation is the active current, and the second term is the reactive current.

[0078] Based on formula (3), the analytical expression of the dynamic power injected into the grid connection point by the grid-connected SVG converter during the grid voltage transient period can be obtained as follows:

[0079] (4)

[0080] In the formula, U t is the AC voltage amplitude at the grid connection point, j is an imaginary unit, solve for reactive power Q right U t The derivative of is:

[0081] (5)

[0082] In the formula, E Determined by the virtual excitation control module.

[0083] The voltage support strength of the grid-type SVG converter during transient conditions can be evaluated by equation (5).

[0084] When a fault causes the system voltage U t When the power is reduced, the grid-type SVG should output reactive power Q To do this, it is necessary to meet , and the absolute value It is large enough to output as much reactive power as possible per unit time, and the voltage support capacity is also stronger.

[0085] Combining equation (2) and equation (5) can be optimized from the following perspectives:

[0086] After the grid transient, E The larger the amplitude, The larger the absolute value, the faster the reactive power response of the SVG during the grid voltage transient period, and the greater the voltage support strength. According to formula (2), the internal potential amplitude is E The expression of the adjustable parameters includes: regulator gain K , virtual excitation winding time constant T ’ d0 , first voltage regulator time constant T 1 and the second voltage regulator time constant T 2 .

[0087] Step S104: adjusting the adjustable parameters to improve the voltage support capability of the SVG converter.

[0088] Further, step S104 includes:

[0089] The adjustable parameters are adjusted to increase the bandwidth of the virtual excitation control module, thereby improving the voltage support capability of the SVG converter.

[0090] Specifically, by adjusting one, two or more of the adjustable parameters, the bandwidth of the virtual excitation control module is increased and the response is faster, so that the unit time is E The larger the amplitude, the more optimized the voltage support capability of the grid-type SVG converter during transient periods. For example, adjusting the regulator gain K Increase and / or adjust the virtual field winding time constant T ’ d0 Reducing and / or adjusting the first voltage regulator time constant T 1 Increasing and / or adjusting the second voltage regulator time constant T 2 Preferably, the regulator gain is adjusted K Increase and virtual excitation winding time constant T ’ d0 Reduce to increase the bandwidth of the virtual excitation control module, thereby improving the voltage support capability of the SVG converter.

[0091] Furthermore, adjusting the adjustable parameters includes:

[0092] The particle swarm optimization algorithm is used to optimize the adjustable parameters.

[0093] Since the SVG model is nonlinear, it is difficult to use analytical methods to analyze the adjustable parameters. T ’ d0 , T 1 and T 2 The particle swarm optimization algorithm has the advantages of being easy to implement and having a fast convergence speed, so the particle swarm optimization algorithm is used in this embodiment to optimize the above parameters.

[0094] Figure 4 FIG. 4 shows an exemplary flow chart of an adjustable parameter optimization process based on a particle swarm algorithm according to an embodiment of the present invention. Figure 4 As shown, the specific optimization steps are as follows:

[0095] (1) Randomly generate a certain number of particles and initialize the particle dimension, particle position and particle velocity;

[0096] (2) Assigning particles to adjustable parameters T ’ d0 , T 1 and T 2 , and run the simulation model to calculate the objective function;

[0097] (3) Compare the objective function values ​​in the iteration process and update the local optimal value of the particle and the global optimal solution;

[0098] (4) Update the particle velocity and position, and limit the particle position and velocity within a limited range;

[0099] (5) Determine whether the algorithm has reached the maximum number of iterations or meets the convergence condition. If so, terminate the algorithm and output the optimized time constant value. Otherwise, return to step (2).

[0100] According to the previous analysis, the faster the SVG voltage response is, the more reactive power is output per unit time, which is more beneficial to the transient process of the system. Therefore, in this embodiment, an objective function based on the absolute value of the voltage deviation multiplied by the time integral is adopted, and the expression is as follows:

[0101] ;

[0102] In the formula, T 1 is a time constant, which is usually larger to ensure that the system can enter a stable state. t 0 The time when the fault occurs.

[0103] In the above-mentioned embodiment, based on the SVG converter model of virtual excitation control, the internal potential phase and internal potential amplitude of the SVG converter are obtained. Based on the internal potential phase and internal potential amplitude, the SVG converter is equivalent to a voltage source series impedance as a simplified model of the SVG converter. Based on the simplified model of the SVG converter, adjustable parameters are obtained, and the adjustable parameters are adjusted to improve the voltage support capability of the SVG converter. This can increase the rate at which the SVG converter outputs reactive power during transient periods, improve the voltage support capability of the SVG converter, and thereby improve the voltage strength of the power system.

[0104] Example 1

[0105] In order to verify the effectiveness of the proposed control device, according to Figure 2 The model structure was used for relevant simulation experiments. At t=1s, the grid voltage dropped and lasted for 0.06s. Figure 5 A simulation data diagram comparing the voltage support capability of a meshed SVG converter before and after the method for improving the voltage support capability of a meshed SVG converter according to an embodiment of the present invention is shown. Figure 5As shown, by adopting the remodeling control method for improving the voltage support capability of the SVG converter provided by the embodiment of the present invention, after adjusting the adjustable parameters, the rate at which the SVG converter outputs reactive power is significantly improved, and the voltage recovery rate is also improved accordingly. Therefore, in the transient process, the voltage support strength of the SVG converter is also increased. The simulation results verify the effectiveness of the remodeling control method for improving the voltage support capability of the SVG converter provided by the embodiment of the present invention.

[0106] Figure 6 A schematic structural diagram of a remodeling control device for improving the voltage support capability of a grid-type SVG converter according to an embodiment of the present invention is shown.

[0107] like Figure 6 As shown, the remodeling control device is applied to a grid-type SVG converter, comprising:

[0108] The first processing unit 601 is used to obtain the internal potential phase and internal potential amplitude of the SVG converter based on the SVG converter model of virtual excitation control;

[0109] A simplification unit 602 is used to convert the SVG converter into a voltage source series impedance based on the internal potential phase and the internal potential amplitude, so as to serve as a simplified model of the SVG converter;

[0110] A second processing unit 603 is used to obtain adjustable parameters based on the simplified model of the SVG converter;

[0111] The adjustment unit 604 is used to adjust the adjustable parameters to improve the voltage support capability of the SVG converter.

[0112] Furthermore, the internal potential phase is as follows:

[0113] ;

[0114] in, ω 0 is the rated angular frequency, K p is the power synchronization coefficient, P ref is the power reference value, P e is the output power of the SVG converter, s is the Laplace operator, t For time;

[0115] The internal potential amplitude is as follows:

[0116] ;

[0117] in, K is the regulator gain, Kv Select the factor for proportional-integral, T 1 and T 2 are the first voltage regulator time constant and the second voltage regulator time constant, respectively, U t * is the reference value of the AC voltage amplitude at the grid connection point, U t is the AC voltage amplitude at the grid connection point, T ’ d0 is the time constant of the virtual excitation winding.

[0118] Furthermore, the second processing unit 603 is further configured to:

[0119] Based on the simplified model of SVG converter, the derivative of the reactive power of the simplified model of SVG converter to the AC voltage amplitude of the grid connection point is obtained;

[0120] Based on the derivatives, adjustable parameters are obtained.

[0121] Furthermore, the derivative of the reactive power of the simplified SVG converter model with respect to the AC voltage amplitude at the grid connection point is as follows:

[0122] ;

[0123] in, Q is the reactive power, U t is the AC voltage amplitude at the grid connection point, E is the internal potential amplitude, θ is the internal potential phase, x c For the reactance.

[0124] Furthermore, the adjustable parameters include: regulator gain K , virtual excitation winding time constant T ’ d0 , first voltage regulator time constant T 1 and the second voltage regulator time constant T 2 .

[0125] Furthermore, the adjusting unit 604 is further configured to:

[0126] The adjustable parameters are adjusted to increase the bandwidth of the virtual excitation control module, thereby improving the voltage support capability of the SVG converter.

[0127] In the above-mentioned embodiment, based on the SVG converter model of virtual excitation control, the internal potential phase and internal potential amplitude of the SVG converter are obtained. Based on the internal potential phase and internal potential amplitude, the SVG converter is equivalent to a voltage source series impedance as a simplified model of the SVG converter. Based on the simplified model of the SVG converter, adjustable parameters are obtained, and the adjustable parameters are adjusted to improve the voltage support capability of the SVG converter. This can increase the rate at which the SVG converter outputs reactive power during transient periods, improve the voltage support capability of the SVG converter, and thereby improve the voltage strength of the power system.

[0128] It should be noted that the device provided in the above embodiment only uses the division of the above functional modules as an example to implement its functions. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device is divided into different functional modules to complete all or part of the functions described above. In addition, the device and method embodiments provided in the above embodiment belong to the same concept, and their specific implementation process is detailed in the method embodiment, which will not be repeated here.

[0129] An embodiment of the present invention further provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the reshaping control method for improving the voltage support capability of the grid-type SVG converter provided in the above-mentioned embodiments is implemented.

[0130] An embodiment of the present invention also provides an electronic device, comprising: a processor; a memory for storing processor executable instructions; the processor is used to read the executable instructions from the memory and execute the instructions to implement the reshaping control method for improving the voltage support capability of the grid-type SVG converter provided in the above-mentioned embodiments.

[0131] The invention has been described above with reference to a few embodiments. However, it is readily apparent to a person skilled in the art that other embodiments than the ones disclosed above are equally within the scope of the invention, as defined by the appended patent claims.

[0132] Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise herein. All references to "a / said / the [means, components, etc.]" are to be openly interpreted as at least one instance of the means, components, etc., unless explicitly stated otherwise. The steps of any method disclosed herein do not necessarily have to be performed in the exact order disclosed, unless explicitly stated otherwise.

[0133] It should be understood by those skilled in the art that the embodiments of the present invention may be provided as methods, systems or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment or an embodiment combining software and hardware aspects. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0134] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0135] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0136] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0137] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A remodeling control method for improving the voltage support capability of a grid-type SVG converter, characterized in that: Applied to a grid-type SVG converter, the reshaping control method includes: Based on the SVG converter model of virtual excitation control, the internal potential phase and internal potential amplitude of the SVG converter are obtained; Based on the internal potential phase and the internal potential amplitude, the SVG converter is equivalent to a voltage source in series with an impedance to serve as a simplified model of the SVG converter; Based on the simplified model of the SVG converter, adjustable parameters are obtained; Adjusting the adjustable parameters to improve the voltage support capability of the SVG converter; Wherein, the internal potential phase is as follows: ； in, ω 0 is the rated angular frequency, K p is the power synchronization coefficient, P ref is the power reference value, P e is the output power of the SVG converter, s is the Laplace operator, t For time; The internal potential amplitude is as follows: ； in, K is the regulator gain, K v Select the factor for proportional-integral, T 1 and T 2 are the first voltage regulator time constant and the second voltage regulator time constant, U t * is the reference value of the AC voltage amplitude at the grid connection point, U t is the AC voltage amplitude at the grid connection point, T ’ d0 is the time constant of virtual excitation winding; Among them, based on the simplified model of the SVG converter, the adjustable parameters are obtained, including: Based on the simplified SVG converter model, a derivative of the reactive power of the simplified SVG converter model with respect to the AC voltage amplitude at the grid connection point is obtained; Based on the derivative, an adjustable parameter is obtained; The derivative of the reactive power of the simplified SVG converter model to the AC voltage amplitude at the grid connection point is as follows: ； in, Q is the reactive power, U t is the AC voltage amplitude at the grid connection point, E is the internal potential amplitude, θ is the internal potential phase, x c For the reactance.

2. The remodeling control method according to claim 1, characterized in that: The adjustable parameters include: regulator gain K , virtual excitation winding time constant T ’ d0 , first voltage regulator time constant T 1 and 2 voltage regulator time constants T 2.

3. The remodeling control method according to claim 1, characterized in that: Adjusting the adjustable parameters to improve the voltage support capability of the SVG converter includes: The adjustable parameters are adjusted to increase the bandwidth of the virtual excitation control module, thereby improving the voltage support capability of the SVG converter.

4. A remodeling control device for improving the voltage support capability of a grid-type SVG converter, characterized in that: Applied to a grid-type SVG converter, the reshaping control device comprises: A first processing unit is used to obtain an internal potential phase and an internal potential amplitude of the SVG converter based on a virtual excitation control SVG converter model; A simplification unit, used for converting the SVG converter into a voltage source series impedance form based on the internal potential phase and the internal potential amplitude, so as to serve as a simplified model of the SVG converter; A second processing unit, configured to obtain adjustable parameters based on the simplified model of the SVG converter; An adjustment unit, used for adjusting the adjustable parameters to improve the voltage support capability of the SVG converter; Wherein, the internal potential phase is as follows: ； in, ω 0 is the rated angular frequency, K p is the power synchronization coefficient, P ref is the power reference value, P e is the output power of the SVG converter, s is the Laplace operator, t For time; The internal potential amplitude is as follows: ； in, K is the regulator gain, K v Select the factor for proportional-integral, T 1 and T 2 are the first voltage regulator time constant and the second voltage regulator time constant, U t * is the reference value of the AC voltage amplitude at the grid connection point, U t is the AC voltage amplitude at the grid connection point, T ’ d0 is the time constant of virtual excitation winding; Wherein, the second processing unit is further used for: Based on the simplified SVG converter model, a derivative of the reactive power of the simplified SVG converter model with respect to the AC voltage amplitude at the grid connection point is obtained; Based on the derivative, an adjustable parameter is obtained; The derivative of the reactive power of the simplified SVG converter model to the AC voltage amplitude at the grid connection point is as follows: ； in, Q is the reactive power, U t is the AC voltage amplitude at the grid connection point, E is the internal potential amplitude, θ is the internal potential phase, x c For the reactance.

5. The remodeling control device according to claim 4, characterized in that: The adjustable parameters include: regulator gain K , virtual excitation winding time constant T ’ d0 , first voltage regulator time constant T 1 and 2 voltage regulator time constants T 2.

6. The remodeling control device according to claim 4, characterized in that: The regulating unit is further used for: The adjustable parameters are adjusted to increase the bandwidth of the virtual excitation control module, thereby improving the voltage support capability of the SVG converter.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the remodeling control method described in any one of claims 1 to 3 is implemented.

8. An electronic device, comprising: processor; a memory for storing instructions executable by the processor; The processor is used to read the executable instructions from the memory and execute the instructions to implement the reshaping control method according to any one of claims 1 to 3.

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