Harmonic compensation control method, device and equipment of active filter and storage medium

Abstract

The application provides a harmonic compensation control method and device of an active filter, equipment and a storage medium, and relates to the technical field of active filter control. The method comprises: collecting a network-side voltage and a network-side current of a three-phase power system. Then, the network-side voltage and the network-side current are subjected to harmonic analysis, and based on a first harmonic analysis result of the network-side voltage and a second harmonic analysis result of the network-side current, a harmonic compensation control model is constructed for an active filter in the power load system. Further, a preset algorithm is used to locally solve the harmonic compensation control model to determine a reference current of the active filter. The active filter is controlled to output a harmonic compensation current identical to the reference current. The application can control the active filter to accurately generate a required harmonic compensation current.

Description

Technical Field

[0001] This application relates to the field of active filter control technology, and in particular to a harmonic compensation control method, apparatus, device and storage medium for an active filter. Background Technology

[0002] In modern power systems, with the widespread application of industrial automation, renewable energy integration, and power electronic devices, the proportion of nonlinear loads has increased significantly. Nonlinear loads generate a large amount of harmonic current during operation, leading to increasingly severe distortions in the current and voltage waveforms of the power system. Therefore, an active filter control method capable of achieving efficient harmonic suppression is needed.

[0003] In existing technologies, a typical approach involves introducing an improved swarm intelligence optimization algorithm to globally search and optimize the control parameters of the active filter, and then using the optimized control parameters to generate a reference command for the harmonic compensation current. Another approach improves the detection accuracy of the standard fundamental frequency through an improved Clarke transform and filter design, thereby generating a reference command for the harmonic compensation current.

[0004] However, existing technologies are ill-suited to meet the real-time response requirements of dynamic load changes and power system disturbances, thus affecting the accurate generation of harmonic compensation current. Summary of the Invention

[0005] This application provides a harmonic compensation control method, apparatus, device, and storage medium for an active filter, to solve the technical problem that the harmonic compensation current cannot be accurately generated in the prior art.

[0006] In a first aspect, this application provides a harmonic compensation control method for an active filter, comprising:

[0007] The grid-side voltage and grid-side current of a three-phase power system are collected; wherein, the three-phase power system is used to supply power to the power load system, the grid-side voltage represents the voltage at the connection point between the three-phase power system and the user incoming main cabinet in the power load system, and the grid-side current represents the current at the connection point between the three-phase power system and the user incoming main cabinet;

[0008] Harmonic analysis is performed on the grid-side voltage and grid-side current to obtain the first harmonic analysis result of the grid-side voltage and the second harmonic analysis result of the grid-side current; based on the first harmonic analysis result and the second harmonic analysis result, a harmonic compensation control model is constructed for the active filter in the power load system;

[0009] A preset algorithm is used to locally solve the harmonic compensation control model to determine the reference current of the active filter; the active filter is then controlled to output a harmonic compensation current that is the same as the reference current.

[0010] In one possible design, the preset algorithm is the trust region projection gradient algorithm;

[0011] The harmonic compensation control model is locally solved using a preset algorithm to determine the reference current of the active filter, including:

[0012] The trust region projection gradient algorithm is used to locally solve the harmonic compensation control model to obtain the admittance coefficients of each harmonic; wherein, the admittance coefficients of each harmonic characterize the impedance characteristics of the three-phase power system at a preset harmonic frequency, and the preset harmonic frequency is a frequency that is a preset multiple of the standard fundamental frequency.

[0013] Based on the admittance coefficients of each harmonic, the reference current components of each harmonic are calculated; based on the reference current components of each harmonic, the reference current of the active filter is generated.

[0014] In one possible design, the trust region projection gradient algorithm is used to locally solve the harmonic compensation control model, including:

[0015] The harmonic compensation control model is simulated based on a preset local quadratic model, and the preset local quadratic model is solved using the trust region projection gradient algorithm.

[0016] In the process of solving the preset local quadratic model, the variable update direction of the preset local quadratic model indicated by the trust region projection gradient algorithm is determined, and the variable update direction is corrected to the feasible region of the harmonic compensation control model; and the trust region radius of the trust region projection gradient algorithm is dynamically adjusted.

[0017] When the descent gradient of the trust region projection gradient algorithm satisfies the first preset condition, or when the number of iterations of the trust region projection gradient algorithm satisfies the second preset condition, the solution of the preset local quadratic model is stopped.

[0018] In one possible design, the first harmonic analysis result includes the voltage harmonic components and the effective values ​​of the voltage harmonic components of the grid-side voltage; the second harmonic analysis result includes the current harmonic components and the effective values ​​of the current harmonic components of the grid-side current.

[0019] In one possible design, based on the first harmonic analysis results and the second harmonic analysis results, a harmonic compensation control model is constructed for the active filter in the power load system, including:

[0020] Based on the effective values ​​of each voltage harmonic component and each current harmonic component, the apparent power of the three-phase power system is calculated.

[0021] Determine the effective value of the target current harmonic component that is greater than the preset current threshold among the effective values ​​of each current harmonic component.

[0022] A preset penalty term is set for the effective value of the target current harmonic component; and an optimization target is defined based on the apparent power and the preset penalty term; based on the optimization target, a harmonic compensation control model is constructed for the active filter in the power load system.

[0023] In one possible design, the method further includes:

[0024] Set voltage total harmonic distortion rate constraints, voltage single harmonic distortion rate constraints, and system power balance constraints for the harmonic compensation control model;

[0025] The voltage total harmonic distortion rate constraint indicates that the total harmonic distortion rate of the grid-side voltage is less than or equal to a first preset threshold; the voltage single harmonic distortion rate constraint indicates that the distortion rate of each voltage harmonic component of the grid-side voltage is less than or equal to a second preset threshold; and the system power balance constraint indicates that the active power of the three-phase power system is in a preset balance state.

[0026] In one possible design, the method further includes:

[0027] The load current of the three-phase power system is collected, and harmonic analysis is performed on the load current to determine the current harmonic components and effective values ​​of each current harmonic component; wherein, the load current represents the current flowing through the electrical terminals included in the power load system;

[0028] The effective values ​​of the target current harmonic components that are greater than a preset current threshold are obtained from the effective values ​​of each current harmonic component of the grid-side current, as well as the target harmonic order and target current harmonic component corresponding to the effective values ​​of the target current harmonic components.

[0029] The current harmonic components of each load current at the target harmonic order are matched with the target current harmonic components to determine the target load current corresponding to the current harmonic component that is successfully matched with the target current harmonic component.

[0030] The power terminal corresponding to the target load current is determined, and the harmonic compensation current output by the active filter is injected into the power terminal.

[0031] Secondly, this application provides a harmonic compensation control device for an active filter, comprising:

[0032] The acquisition module is used to acquire the grid-side voltage and grid-side current of the three-phase power system; wherein, the three-phase power system is used to supply power to the power load system, the grid-side voltage represents the voltage at the connection point between the three-phase power system and the user incoming line cabinet in the power load system, and the grid-side current represents the current at the connection point between the three-phase power system and the user incoming line cabinet;

[0033] The analysis module is used to perform harmonic analysis on the grid-side voltage and grid-side current to obtain the first harmonic analysis result of the grid-side voltage and the second harmonic analysis result of the grid-side current;

[0034] A construction module is used to construct a harmonic compensation control model for an active filter in a power load system based on the first harmonic analysis results and the second harmonic analysis results.

[0035] The solution module is used to perform local solution of the harmonic compensation control model using a preset algorithm to determine the reference current of the active filter;

[0036] The control module is used to control the active filter to output a harmonic compensation current that is the same as the reference current.

[0037] In one possible design, the preset algorithm is the trust region projection gradient algorithm;

[0038] The solution module includes:

[0039] The solution submodule is used to locally solve the harmonic compensation control model using the trust region projection gradient algorithm to obtain the admittance coefficients of each harmonic; wherein, the admittance coefficients of each harmonic characterize the impedance characteristics of the three-phase power system at a preset harmonic frequency, and the preset harmonic frequency is a frequency that is a preset multiple of the standard fundamental frequency.

[0040] The first calculation submodule is used to calculate the reference current components of each harmonic based on the admittance coefficients of each harmonic.

[0041] A generation submodule is used to generate the reference current of the active filter based on the reference current components of each harmonic.

[0042] In one possible design, the solution submodule includes:

[0043] The processing component is used to simulate the harmonic compensation control model based on a preset local quadratic model, and to solve the preset local quadratic model using the trust region projection gradient algorithm.

[0044] A component is defined to determine the variable update direction of the preset local quadratic model as indicated by the trust region projection gradient algorithm during the process of solving the preset local quadratic model.

[0045] A correction component is used to correct the direction of the variable update to the feasible region of the harmonic compensation control model;

[0046] An adjustment component is used to dynamically adjust the trust region radius of the trust region projection gradient algorithm.

[0047] The processing component is further configured to stop solving the preset local quadratic model when the descent gradient of the trust region projection gradient algorithm satisfies a first preset condition, or when the number of iterations of the trust region projection gradient algorithm satisfies a second preset condition.

[0048] In one possible design, the first harmonic analysis result includes the voltage harmonic components and the effective values ​​of the voltage harmonic components of the grid-side voltage; the second harmonic analysis result includes the current harmonic components and the effective values ​​of the current harmonic components of the grid-side current.

[0049] In one possible design, the building block includes:

[0050] The second calculation submodule is used to calculate the apparent power of the three-phase power system based on the effective values ​​of the voltage harmonic components and the effective values ​​of the current harmonic components.

[0051] The determination submodule is used to determine the effective value of the target current harmonic component that is greater than a preset current threshold among the effective values ​​of each current harmonic component.

[0052] The configuration submodule is used to set a preset penalty term for the effective value of the target current harmonic component;

[0053] Define a submodule for defining an optimization objective based on the apparent power and the preset penalty term;

[0054] A submodule is constructed to build a harmonic compensation control model for active filters in a power load system based on the optimization objective.

[0055] In one possible design, the setting submodule is further configured to:

[0056] Set voltage total harmonic distortion rate constraints, voltage single harmonic distortion rate constraints, and system power balance constraints for the harmonic compensation control model;

[0057] The voltage total harmonic distortion rate constraint indicates that the total harmonic distortion rate of the grid-side voltage is less than or equal to a first preset threshold; the voltage single harmonic distortion rate constraint indicates that the distortion rate of each voltage harmonic component of the grid-side voltage is less than or equal to a second preset threshold; and the system power balance constraint indicates that the active power of the three-phase power system is in a preset balance state.

[0058] In one possible design, the acquisition module is also used to acquire the load current of the three-phase power system;

[0059] The analysis module is also used to perform harmonic analysis on the load current to determine the current harmonic components and effective values ​​of each current harmonic component of the load current; wherein, the load current represents the current flowing through the electrical terminals included in the power load system;

[0060] The active filter harmonic compensation control device further includes: an acquisition module, a matching module, and an injection module;

[0061] The acquisition module is used to acquire the effective value of the target current harmonic component that is greater than a preset current threshold among the effective values ​​of each current harmonic component of the grid-side current, as well as the target harmonic number and target current harmonic component corresponding to the effective value of the target current harmonic component.

[0062] The matching module is used to match the current harmonic components of each load current at the target harmonic order with the target current harmonic components, and determine the target load current corresponding to the current harmonic component that is successfully matched with the target current harmonic components.

[0063] The injection module is used to determine the power terminal corresponding to the target load current and inject the harmonic compensation current output by the active filter into the power terminal.

[0064] Thirdly, this application provides an electronic device comprising: at least one processor and a memory; the memory storing computer-executable instructions; the at least one processor executing the computer-executable instructions stored in the memory, causing the at least one processor to perform the method described in the first aspect above and various possible designs.

[0065] Fourthly, embodiments of this application provide a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, implement the methods described in the first aspect above and various possible designs.

[0066] Fifthly, embodiments of this application provide a computer program product, including a computer program that, when executed by a processor, implements the methods described in the first aspect above and various possible designs.

[0067] This application provides a harmonic compensation control method, device, equipment, and storage medium for an active power filter. It collects the grid-side voltage and grid-side current of a three-phase power system. The three-phase power system supplies power to the power load system. The grid-side voltage represents the voltage at the connection point between the three-phase power system and the user's incoming main cabinet in the power load system, and the grid-side current represents the current at the connection point. Harmonic analysis is then performed on the grid-side voltage and grid-side current to obtain the first harmonic analysis result for the grid-side voltage and the second harmonic analysis result for the grid-side current. Based on the first and second harmonic analysis results, a harmonic compensation control model is constructed for the active power filter in the power load system. Furthermore, a preset algorithm is used to locally solve the harmonic compensation control model to determine the reference current of the active power filter, thereby controlling the output of the active power filter to be the same as the reference current as the harmonic compensation current. Combining the first and second harmonic analysis results, multiple dynamic constraints are introduced into the harmonic compensation control model to ensure that each harmonic component meets the power quality standards. Furthermore, the trust-region projection gradient algorithm is used to locally solve the harmonic compensation control model, which significantly reduces computational complexity and improves the algorithm's convergence speed, thereby adapting to the real-time response requirements of dynamic load changes and three-phase power system disturbances. Therefore, this application combines model construction with dynamic constraints with the trust-region projection gradient algorithm to control the active filter to accurately generate the required harmonic compensation current. Attached Figure Description

[0068] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0069] Figure 1 A flowchart illustrating the harmonic compensation control method for an active filter provided in this application embodiment. Figure 1 ;

[0070] Figure 2 A schematic diagram of the power engineering system structure of the harmonic compensation control method for active filters provided in the embodiments of this application;

[0071] Figure 3 A scenario illustration of the harmonic compensation control method for active filters provided in this application embodiment. Figure 1 ;

[0072] Figure 4 A scenario illustration of the harmonic compensation control method for active filters provided in this application embodiment. Figure 2 ;

[0073] Figure 5 A scenario illustration of the harmonic compensation control method for active filters provided in the embodiments of this application. Figure 3 ;

[0074] Figure 6 A flowchart illustrating the harmonic compensation control method for an active filter provided in this application embodiment. Figure 2 ;

[0075] Figure 7 A schematic diagram of the structure of the harmonic compensation control device for an active filter provided in an embodiment of this application;

[0076] Figure 8 This is a hardware structure diagram of the electronic device provided in the embodiments of this application.

[0077] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0078] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0079] The terms "first," "second," "third," "fourth," etc. (if present) in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of the invention described herein can be implemented, for example, in orders other than those illustrated or described herein.

[0080] In this application, the terms "exemplary" or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplary" or "for example" in this application should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of terms such as "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

[0081] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties. Furthermore, the collection, use and processing of the relevant data must comply with relevant laws, regulations and standards, and corresponding operation entry points are provided for users to choose to authorize or refuse.

[0082] Nonlinear loads generate a large number of harmonic currents during operation. These harmonic currents propagate through the power system and cause power quality problems, such as voltage fluctuations, equipment overheating, increased reactive power, and decreased power factor, especially under conditions of power system voltage distortion or three-phase imbalance.

[0083] In modern power systems, with the widespread application of industrial automation, renewable energy integration, and power electronic devices, the proportion of nonlinear loads (such as rectifiers, frequency converters, uninterruptible power supplies, etc.) in power systems has increased significantly, leading to increasingly serious distortion problems in the current and voltage waveforms of power systems.

[0084] In industrial settings, large motor frequency converters may generate high-order harmonics; in residential power consumption, the connection of a large number of single-phase loads can easily cause three-phase imbalance; in new energy grid connection scenarios, equipment such as photovoltaic inverters and wind power converters will also introduce harmonic components.

[0085] As a new type of power electronic device for suppressing harmonics and compensating for reactive power, active filters urgently require a control method that can achieve efficient harmonic suppression under complex power system conditions.

[0086] In existing technologies, a typical approach involves introducing an improved swarm intelligence optimization algorithm to globally search and optimize the control parameters of the active filter, and then using the optimized control parameters to generate a reference command for the harmonic compensation current. Another approach improves the detection accuracy of the standard fundamental frequency through an improved Clarke transform and filter design, thereby generating a reference command for the harmonic compensation current.

[0087] However, existing active filter control schemes based on swarm intelligence optimization algorithms rely on global iterative search, which involves large computational loads and slow convergence speeds. In scenarios with dynamic load changes or severe voltage distortion in the power system, they suffer from insufficient response speed and poor real-time performance, making it difficult to meet the requirements for high-precision harmonic suppression.

[0088] Existing active filter control schemes based on improved Clark transform and filter design rely on a fixed active filter structure and transform method, and the harmonic constraints are based on overall optimization. Because this method does not introduce a dynamic optimization algorithm to iteratively constrain harmonic components, its ability to suppress each harmonic component is limited when multiple harmonics are superimposed due to dynamic load changes.

[0089] Therefore, existing technologies are unable to adapt to the real-time response requirements of dynamic load changes and power system disturbances, thus affecting the accurate generation of harmonic compensation current.

[0090] Starting with existing technical problems, the inventors first analyzed the core challenge of active power filter control under voltage distortion and imbalance conditions: how to accurately suppress harmonics in scenarios with dynamic load changes and the superposition of multiple harmonics. To address this challenge, the inventors proposed performing harmonic analysis on the voltage and current of the power system and constructing a model based on the analysis results, thereby attempting to introduce dynamic constraints. Subsequently, addressing the computational complexity issue of existing algorithms, the feasibility of the trust-region projection gradient algorithm was explored. This algorithm approximates the objective function through a local quadratic model, significantly reducing computational complexity and improving convergence speed. Finally, the inventors combined the model construction with dynamic constraints with the trust-region projection gradient algorithm to obtain accurate reference commands for harmonic compensation current.

[0091] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0092] This application provides a harmonic compensation control method for an active filter. Figure 1 A flowchart illustrating the harmonic compensation control method for an active filter provided in this application embodiment. Figure 1 .like Figure 1 As shown, the harmonic compensation control method for the active filter includes:

[0093] S101. Collect the grid-side voltage and grid-side current of the three-phase power system.

[0094] It should be understood that a three-phase power system is used to supply power to the power load system. The user incoming main switchboard serves as the starting point for user operation and maintenance of the power load system, and is also the main switch for all power-consuming terminals included in the power load system. The first core control node that the three-phase AC power output from the three-phase power system passes through after entering the power load system is the user incoming main switchboard.

[0095] Explanatory: Grid-side voltage refers to the voltage at the connection point between the three-phase power system and the user's incoming main control cabinet; grid-side current refers to the current at the connection point between the three-phase power system and the user's incoming main control cabinet. For example... Figure 2 A schematic diagram of the power engineering system structure for the harmonic compensation control method of the active filter provided in the embodiments of this application is shown below. Figure 2 As shown, the three-phase power system and the power load system together constitute the power engineering system. It is obvious that... Figure 2 Marked in , and This is the grid-side voltage. , and This represents the grid-side current.

[0096] also, Figure 2 The power load system shown includes not only the main incoming switchboard for users, but also active filters and power terminals. In this example, the power terminal is a three-phase rectified bridged resistive-inductive load. This is the DC-side capacitor of the active filter. This is the DC-side voltage of the active filter. The output inductor of the active filter, The output resistance of the active filter. This is the output capacitor of the active filter. This is the DC-side capacitor of the three-phase rectifier bridge. The line resistance of a three-phase power system. It represents the line inductance of a three-phase power system.

[0097] It is worth noting that, , and It is the load current of a three-phase power system, that is, the current flowing through the user terminals included in the power load system.

[0098] S102. Perform harmonic analysis on the grid-side voltage and grid-side current to obtain the first harmonic analysis result of the grid-side voltage and the second harmonic analysis result of the grid-side current; based on the first harmonic analysis result and the second harmonic analysis result, construct a harmonic compensation control model for the active filter in the power load system.

[0099] The first harmonic analysis results include the voltage harmonic components and the effective values ​​of each voltage harmonic component of the grid-side voltage, while the second harmonic analysis results include the current harmonic components and the effective values ​​of each current harmonic component of the grid-side current.

[0100] Specifically, the harmonic analysis process for grid-side voltage and current is as follows: The acquired grid-side voltage (current) is sequentially transformed into multiple reference coordinate systems rotated according to different harmonic frequencies, where the harmonic frequencies are integer multiples of the standard fundamental frequency (50Hz). At this time, the relative motion relationship of different frequency components in the grid-side voltage (current) changes. In each reference coordinate system, frequency components with the same harmonic frequency as the reference coordinate system appear in DC form, while frequency components with different harmonic frequencies appear in AC form. The frequency components appearing in DC form are extracted from each reference coordinate system. These extracted frequency components are then passed through a low-pass filter and subjected to an anti-synchronous rotation transformation to obtain the harmonic components of the grid-side voltage (current).

[0101] Furthermore, based on the voltage (current) harmonic components, the effective value of each harmonic component is calculated. Specifically, the effective value of each voltage (current) harmonic component is obtained by taking the root mean square of the harmonic components. However, for ease of calculation, it is usually performed by dividing each voltage (current) harmonic component by... It is considered as the effective value of each voltage (current) harmonic component.

[0102] Next, in constructing a harmonic compensation control model for the active filter in the power load system based on the results of the first and second harmonic analyses, it is first necessary to calculate the apparent power of the three-phase power system based on the effective values ​​of each voltage harmonic component and each current harmonic component. The apparent power is the product of the total effective value of the voltage and the total effective value of the current, representing the total power capacity required by the three-phase power system. The total effective value of the voltage is the square root of the sum of the squares of the effective values ​​of each voltage harmonic component, and the total effective value of the current is the square root of the sum of the squares of the effective values ​​of each current harmonic component.

[0103] It should be understood that during the normal operation of a three-phase power system, the effective value of each current harmonic component is not allowed to exceed a certain preset current threshold, namely the harmonic current emission limit. This limit is a legally mandated upper limit, which specifies the maximum effective value of each current harmonic component that is allowed to be injected into the public power grid.

[0104] For current harmonic components exceeding a preset current threshold (harmonic current emission limit), penalties such as fines or capacity limits are required. In this embodiment, the effective value of the target current harmonic component that exceeds the preset current threshold is determined among the effective values ​​of each current harmonic component, and a preset penalty item is set for the effective value of the target current harmonic component.

[0105] Next, an optimization objective is defined based on apparent power and a preset penalty term. In this embodiment, the optimization objective is defined as minimizing the sum of apparent power and the preset penalty term. Furthermore, a harmonic compensation control model is constructed for the active filter in the power load system based on the optimization objective. Specifically, the constructed harmonic compensation control model is as follows:

[0106]

[0107] In the formula, Represents the admittance coefficients of each harmonic. Indicates the first Subharmonic admittance coefficient Indicates the first RMS value of the second voltage harmonic component Indicates the preset penalty item. This represents the weighting coefficient of the preset penalty term. Indicates the harmonic order.

[0108] Among them, the preset penalty items The expression is as follows:

[0109]

[0110]

[0111] In the formula, Represents the admittance coefficient of the first harmonic. This represents the effective value of the first voltage harmonic component, which is the standard fundamental frequency. Indicates the first Sensitivity factor for secondary current harmonic components. The first real-time measurement Distortion rate of secondary current harmonic components This represents the limit value for the distortion rate of each current harmonic component. (Explanatory, the first...) The distortion rate of the second current harmonic component is used to measure the distortion rate of the first current harmonic component. The degree of distortion caused by the secondary current harmonic components to the original waveform of the grid-side current.

[0112] Understandably, after constructing the harmonic compensation control model, it is necessary to set constraints for it. In this embodiment, the constraints set for the harmonic compensation control model include: total harmonic distortion rate (THR) constraint, single harmonic distortion rate (SHCR) constraint, and system power balance constraint.

[0113] Specifically, the total harmonic distortion (THD) of the voltage is constrained to be less than or equal to a first preset threshold.

[0114]

[0115] In the formula, the left side of the inequality sign represents the total harmonic distortion rate of the grid-side voltage, and the right side represents... This represents the first preset threshold, i.e., the total harmonic distortion rate limit. The value should be combined with the allowable total harmonic distortion rate of the grid-side current under a specific scenario. And the allowable total harmonic distortion rate of the grid-side voltage under a preset specific scenario. Together, their expression is as follows:

[0116]

[0117] The voltage single harmonic distortion rate constraint is that the distortion rate of each harmonic component of the grid-side voltage is less than or equal to a second preset threshold.

[0118]

[0119] In the formula, the left-hand side of the inequality sign represents the first... The distortion rate of the second voltage harmonic component, on the right side. This represents the second preset threshold, which is the limit value for the single harmonic distortion rate of the current. The value should be combined with the allowable value of the single harmonic distortion rate of the grid-side current under the specific scenario. The allowable value of single harmonic distortion rate of grid-side voltage under preset specific scenarios. Together, their expression is as follows:

[0120]

[0121] It should be noted that, for grid-side voltage, we have:

[0122]

[0123] In the formula, This represents the maximum permissible value for the single harmonic distortion rate of the grid-side voltage. The grid-side voltage includes the first The voltage value of each frequency component.

[0124] The system power balance constraint is that the active power of the three-phase power system is in a preset balance state:

[0125]

[0126] In the formula, This represents the switching and circuit losses in a three-phase power system. This indicates the active load of a three-phase power system.

[0127] S103. Use a preset algorithm to locally solve the harmonic compensation control model to determine the reference current of the active filter; control the output of the active filter to be the same as the reference current as the harmonic compensation current.

[0128] In this embodiment, the preset algorithm used is the trust-region projection gradient algorithm. The harmonic compensation control model is locally solved using the trust-region projection gradient algorithm to obtain the admittance coefficients of each harmonic. Here, each harmonic admittance coefficient refers to the impedance characteristic of the three-phase power system at a preset harmonic frequency, where the preset harmonic frequency is a preset multiple of the standard fundamental frequency (50Hz). Then, based on each harmonic admittance coefficient, the reference current components of each harmonic are calculated, and based on these reference current components, the reference current of the active filter is generated. Here, each harmonic reference current component refers to a reference value set for each harmonic current component generated by the active filter.

[0129] Specifically, the steps for locally solving the harmonic compensation control model using the trust region projection gradient algorithm are as follows:

[0130] Step a1: Simulate the harmonic compensation control model based on the preset local quadratic model, and solve the preset local quadratic model using the trust region projection gradient algorithm.

[0131] Explanatory, in the current variable of the harmonic compensation control model, namely the current harmonic admittance coefficient. Nearby, construct a pre-defined local quadratic model. As a trust region subproblem of the trust region projection gradient algorithm, it is used to approximate the behavior of the harmonic compensation control model under the current variable.

[0132] Among them, the preset local quadratic model is the harmonic compensation control model. exist The second-order approximation at point is expressed mathematically as follows:

[0133]

[0134] In the formula, , indicating the direction of variable updates for the preset local quadratic model. This represents the Hessian matrix.

[0135] Step a2: During the process of solving the preset local quadratic model, determine the variable update direction of the preset local quadratic model indicated by the trust region projection gradient algorithm, and correct the variable update direction to the feasible region of the harmonic compensation control model.

[0136] Specifically, the variable update direction is checked to see if it meets the constraints of the harmonic compensation control model. If not, the variable update direction is corrected to the feasible region of the harmonic compensation control model using the projection operator Π(·). The feasible region of the harmonic compensation control model is determined by the constraints.

[0137] That is, the process of correcting the direction of variable update is as follows:

[0138]

[0139] The expression for the projection operator Π(·) is:

[0140]

[0141] In the formula, Ω represents the feasible region of the harmonic compensation control model, and its expression is as follows:

[0142]

[0143] Step a3: Dynamically adjust the trust region radius of the trust region projection gradient algorithm.

[0144] Specifically, the decrease rate of the preset local quadratic model after the variable update direction is corrected is calculated, and the decrease rate of the preset local quadratic model before correction is compared with the decrease rate of the original local quadratic model. :

[0145]

[0146] Furthermore, based on the decrease ratio The trust region radius of the trust region projection gradient algorithm is dynamically adjusted. For example, when When the value is greater than 0.75, increase the trust region radius. Decrease the trust region radius when it is less than 0.25, and decrease it when it is less than or equal to 0.25. When the value is ≤0.75, the trust region radius remains unchanged.

[0147] Step a4: When the descent gradient of the trust region projection gradient algorithm satisfies the first preset condition, or the number of iterations of the trust region projection gradient algorithm satisfies the second preset condition, stop solving the preset local quadratic model.

[0148] It should be noted that the dynamic adjustment of the trust region radius is an iterative update process, which stops iterating when a certain termination condition is met. The termination condition set in this embodiment is:

[0149]

[0150] In the formula, This represents the descent gradient of the trust region projection gradient algorithm. This indicates the preset convergence threshold. This indicates the number of iterations in the trust region projection gradient algorithm. This indicates the preset maximum number of iterations.

[0151] After locally solving the harmonic compensation control model using the trust region projection gradient algorithm, the admittance coefficients of each harmonic are output. = Then, based on the admittance coefficients of each harmonic, the reference current components of each harmonic are calculated, and the reference current of the active filter is generated. The calculation method for the reference current is as follows:

[0152]

[0153] In the formula, Indicates the reference current. Indicates the measured number of Secondary voltage harmonic components.

[0154] After obtaining the reference current of the active filter, the actual output current of the active filter is compared with the reference current using the built-in hysteresis current controller to obtain the instantaneous error. If the instantaneous error is greater than the preset hysteresis width, the hysteresis current controller controls the active filter to rapidly increase the actual output current; if the instantaneous error is less than the preset hysteresis width, the hysteresis current controller controls the active filter to rapidly decrease the actual output current. Therefore, the hysteresis current controller controls the active filter to ultimately output a harmonic compensation current that is the same as the reference current.

[0155] It should be noted that the active power filter is connected in parallel with the main incoming line cabinet, meaning that the input terminal of the active power filter is directly connected to the main busbar of the main incoming line cabinet. The harmonic compensation current output by the active power filter will flow through the main busbar of the main incoming line cabinet to the electrical terminals affected by harmonics.

[0156] Specifically, the load current of the three-phase power system is collected, and harmonic analysis is performed on the load current to determine the current harmonic components and their effective values. Then, from the effective values ​​of the current harmonic components of the grid-side current, the effective value of the target current harmonic component that is greater than a preset current threshold is found, and the target harmonic order and its corresponding target current harmonic component are determined. Further, the current harmonic components of each load current at the target harmonic order are matched with the target current harmonic component to determine the target load current corresponding to the successfully matched harmonic component. The power terminal corresponding to this target load current is the power terminal affected by harmonics; therefore, the harmonic compensation current output by the active filter will ultimately flow to this power terminal.

[0157] For example, Figure 3A scenario illustration of the harmonic compensation control method for active filters provided in the embodiments of this application. Figure 1 ,like Figure 3 As shown, the current waveform of the load current flowing into a three-phase power system without harmonic compensation is given. Figure 4 A scenario illustration of the harmonic compensation control method for active filters provided in the embodiments of this application. Figure 2 ,like Figure 4 The figure shows the current waveform of the load current flowing into a three-phase power system after harmonic compensation. Clearly, after harmonic compensation, the current waveform of the load current flowing into the three-phase power system is closer to an ideal sine wave.

[0158] In conclusion, Figure 5 A scenario illustration of the harmonic compensation control method for active filters provided in the embodiments of this application. Figure 3 ,like Figure 5 The diagram illustrates the entire generation process of the harmonic compensation current in S101~S103 above. It can be seen that the generation process of the harmonic compensation current can be divided into a model building stage and a model solving stage.

[0159] Explanatory, in Figure 5 In the harmonic compensation control model, the input can be divided into two parts. One part is the effective value of each voltage (current) harmonic component, and the other part is the operating constraints set for the harmonic compensation control model, namely, the total harmonic distortion rate constraint, the single harmonic distortion rate constraint, and the system power balance constraint. The system power balance constraint depends on the switching and circuit losses of the three-phase power system. and active load The settings for total harmonic distortion (THD) and single harmonic distortion (SHD) constraints on voltage depend on the grid-side voltage. ( , , ) and its effective value ( , , ).

[0160] Furthermore, combining the effective values ​​of each voltage (current) harmonic component and operating constraints, the trust-region projection gradient algorithm is used to solve the harmonic compensation control model, outputting the admittance coefficients of each harmonic. Finally, the reference current of the active filter is determined based on the admittance coefficients of each harmonic, thereby controlling the output of the active filter to be the same as the reference current for harmonic compensation.

[0161] Figure 6 A flowchart illustrating the harmonic compensation control method for an active filter provided in this application embodiment. Figure 2 ,like Figure 6 As shown, the model building phase includes:

[0162] S601. Collect grid-side voltage and grid-side current of the three-phase power system.

[0163] S602. Perform harmonic analysis on grid-side voltage and grid-side current to determine the harmonic components of each voltage and their effective values, and the harmonic components of each current and their effective values.

[0164] S603. Based on the voltage harmonic components and their effective values, and the current harmonic components and their effective values, a harmonic compensation control model is constructed.

[0165] The model solution phase includes:

[0166] S604. Construct a preset local quadratic model and solve the preset local quadratic model using the trust region projection gradient algorithm.

[0167] S605. Correct the variable update direction of the preset local quadratic model to the feasible region of the harmonic compensation control model.

[0168] S606. Determine whether the preset termination condition is met. If yes, proceed to S607; otherwise, proceed to S604.

[0169] S607, outputs the admittance coefficients of each harmonic.

[0170] S608. Calculate the reference current components of each harmonic based on the admittance coefficient of each harmonic, and generate the reference current.

[0171] The harmonic compensation control method for active power filters provided in this application collects the grid-side voltage and current of a three-phase power system, performs harmonic analysis on the grid-side voltage and current to obtain the effective values ​​of each voltage harmonic component and each current harmonic component. Then, based on these components, a harmonic compensation control model is constructed. Simultaneously, constraints are set for the total harmonic distortion rate (THD), single harmonic distortion rate (SH), and system power balance of the harmonic compensation control model. Furthermore, a trust-region projection gradient algorithm is used to locally solve the harmonic compensation control model. This algorithm simulates the harmonic compensation control model using a pre-set local quadratic model and corrects the variable update direction of the pre-set local quadratic model in real time, ultimately calculating the reference current of the active power filter, thereby controlling the output of the active power filter to be the same as the reference current as the harmonic compensation current. Combining the effective values ​​of each voltage harmonic component and each current harmonic component, multiple dynamic constraints are introduced into the harmonic compensation control model to ensure that each harmonic component meets power quality standards. Furthermore, the trust-region projection gradient algorithm is used to locally solve the harmonic compensation control model, which significantly reduces computational complexity and improves the algorithm's convergence speed, thereby adapting to the real-time response requirements of dynamic load changes and three-phase power system disturbances. Therefore, this application combines model construction with dynamic constraints with the trust-region projection gradient algorithm to control the active filter to accurately generate the required harmonic compensation current.

[0172] Figure 7 This is a schematic diagram of the structure of the harmonic compensation control device for the active filter provided in the embodiments of this application, as shown below. Figure 7 As shown, the harmonic compensation control device 700 of the active filter includes: an acquisition module 701, an analysis module 702, a construction module 703, a solution module 704, and a control module 705.

[0173] The acquisition module 701 is used to acquire the grid-side voltage and grid-side current of the three-phase power system. The three-phase power system is used to supply power to the power load system. The grid-side voltage represents the voltage at the connection between the three-phase power system and the user incoming main cabinet in the power load system, and the grid-side current represents the current at the connection between the three-phase power system and the user incoming main cabinet.

[0174] Analysis module 702 is used to perform harmonic analysis on grid-side voltage and grid-side current to obtain the first harmonic analysis result of grid-side voltage and the second harmonic analysis result of grid-side current;

[0175] Module 703 is used to construct a harmonic compensation control model for an active filter in a power load system based on the results of the first and second harmonic analysis.

[0176] The solver module 704 is used to perform local solution of the harmonic compensation control model using a preset algorithm to determine the reference current of the active filter;

[0177] The control module 705 is used to control the output of the active filter to have the same harmonic compensation current as the reference current.

[0178] In one possible design, the default algorithm is the trust region projection gradient algorithm;

[0179] Solver module 704 includes:

[0180] The solver submodule 7041 is used to locally solve the harmonic compensation control model using the trust region projection gradient algorithm to obtain the harmonic admittance coefficients of each harmonic. The harmonic admittance coefficients of each harmonic characterize the impedance characteristics of the three-phase power system at a preset harmonic frequency, where the preset harmonic frequency is a preset multiple of the standard fundamental frequency.

[0181] The first calculation submodule 7042 is used to calculate the reference current components of each harmonic based on the admittance coefficient of each harmonic.

[0182] The generation submodule 7043 is used to generate the reference current of the active filter based on the reference current components of each harmonic.

[0183] In one possible design, solving submodule 7041 includes:

[0184] The processing component is used to simulate the harmonic compensation control model based on a preset local quadratic model, and solves the preset local quadratic model using the trust region projection gradient algorithm.

[0185] The component is determined to determine the variable update direction of the preset local quadratic model as indicated by the trust region projection gradient algorithm during the solution process of the preset local quadratic model.

[0186] A correction component is used to correct the variable update direction to the feasible region of the harmonic compensation control model;

[0187] An adjustment component is used to dynamically adjust the trust region radius of the trust region projection gradient algorithm;

[0188] The processing component is also used to stop solving the preset local quadratic model when the descent gradient of the trust region projection gradient algorithm satisfies a first preset condition, or the number of iterations of the trust region projection gradient algorithm satisfies a second preset condition.

[0189] In one possible design, the first harmonic analysis results include the voltage harmonic components and the effective values ​​of the voltage harmonic components of the grid-side voltage; the second harmonic analysis results include the current harmonic components and the effective values ​​of the current harmonic components of the grid-side current.

[0190] In one possible design, building module 703 includes:

[0191] The second calculation submodule 7031 is used to calculate the apparent power of the three-phase power system based on the effective values ​​of each voltage harmonic component and each current harmonic component.

[0192] The determination submodule 7032 is used to determine the effective value of the target current harmonic component that is greater than the preset current threshold among the effective values ​​of each current harmonic component.

[0193] Set submodule 7033 to set a preset penalty term for the effective value of the target current harmonic component;

[0194] Define submodule 7034 to define the optimization target based on apparent power and preset penalty terms;

[0195] Submodule 7035 is constructed to build a harmonic compensation control model for active filters in power load systems based on optimization objectives.

[0196] In one possible design, submodule 7033 is also configured for:

[0197] Set constraints on total harmonic distortion rate of voltage, single harmonic distortion rate of voltage, and system power balance for the harmonic compensation control model;

[0198] Among them, the voltage total harmonic distortion rate constraint indicates that the total harmonic distortion rate of the grid-side voltage is less than or equal to the first preset threshold; the voltage single harmonic distortion rate constraint indicates that the distortion rate of each voltage harmonic component of the grid-side voltage is less than or equal to the second preset threshold; and the system power balance constraint indicates that the active power of the three-phase power system is in a preset balance state.

[0199] In one possible design, the acquisition module 701 is also used to acquire the load current of the three-phase power system;

[0200] The analysis module 702 is also used to perform harmonic analysis on the load current to determine the current harmonic components and effective values ​​of each current harmonic component of the load current; wherein, the load current represents the current flowing through the electrical terminals included in the power load system.

[0201] The active filter harmonic compensation control device 700 further includes: an acquisition module 706, a matching module 707, and an injection module 708;

[0202] The acquisition module 706 is used to acquire the effective value of the target current harmonic component that is greater than the preset current threshold among the effective values ​​of each current harmonic component of the grid-side current, as well as the target harmonic order and target current harmonic component corresponding to the effective value of the target current harmonic component.

[0203] The matching module 707 is used to match the current harmonic components of each load current at the target harmonic order with the target current harmonic components, and to determine the target load current corresponding to the current harmonic component that is successfully matched with the target current harmonic component.

[0204] The injection module 708 is used to determine the power terminal corresponding to the target load current and inject the harmonic compensation current output by the active filter into the power terminal.

[0205] The harmonic compensation control device for active filters provided in this application embodiment can be used to execute the harmonic compensation control method for active filters in any of the above embodiments. Its implementation principle and technical effect are similar, and will not be described again here.

[0206] It should be noted that the division of the various modules in the above device is merely a logical functional division. In actual implementation, they can be fully or partially integrated into a single physical entity, or they can be physically separated. Furthermore, these modules can be implemented entirely in software via processing element calls; they can be fully implemented in hardware; or some modules can be implemented in software via processing element calls, while others are implemented in hardware. Additionally, these modules can be fully or partially integrated together, or implemented independently. The processing element here can be an integrated circuit with signal processing capabilities. During implementation, each step of the above method or each of the above modules can be completed through the integrated logic circuits in the hardware of the processor element or through software instructions.

[0207] Figure 8 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Figure 8 As shown, the electronic device may include: a transceiver 81, a processor 82, and a memory 83.

[0208] Processor 82 executes computer execution instructions stored in memory, causing processor 82 to perform the scheme in the above embodiments. Processor 82 can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components.

[0209] The memory 83 is connected to the processor 82 via the system bus and completes communication between them. The memory 83 is used to store computer program instructions.

[0210] Transceiver 81 can be used to communicate and interact with other devices.

[0211] The system bus can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. The system bus can be divided into address bus, data bus, control bus, etc. For ease of representation, only one thick line is used in the diagram, but this does not indicate that there is only one bus or one type of bus. Transceivers are used to enable communication between database access devices and other computers (e.g., clients, read-write libraries, and read-only libraries). Memory may include random access memory (RAM) and may also include non-volatile memory.

[0212] The electronic device provided in this application embodiment can be used to execute the method provided in any of the above embodiments. Its implementation principle and technical effect are similar, and will not be described again here.

[0213] This application also provides a computer-readable storage medium storing computer instructions that, when executed on a computer, cause the computer to perform the methods provided in any of the above embodiments.

[0214] This application also provides a computer program product, which includes a computer program stored in a computer-readable storage medium. At least one processor can read the computer program from the computer-readable storage medium, and when the at least one processor executes the computer program, it can implement the method provided in any of the above embodiments.

[0215] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative; for instance, the division of modules is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple modules may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be indirect coupling or communication connection through some interfaces, devices, or modules, and may be electrical, mechanical, or other forms.

[0216] The modules described as separate components may or may not be physically separate. The components shown as modules may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to implement the solution of this embodiment according to actual needs.

[0217] Furthermore, the functional modules in the various embodiments of this application can be integrated into one processing unit, or each module can exist physically separately, or two or more modules can be integrated into one unit. The unit composed of the above modules can be implemented in hardware or in the form of hardware plus software functional units.

[0218] The integrated modules described above, implemented as software functional modules, can be stored in a computer-readable storage medium. These software functional modules, stored in a storage medium, include several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) or processor to execute some steps of the methods of the various embodiments of this application.

[0219] It should be understood that the aforementioned processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), etc. A general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in this invention can be directly manifested as execution by a hardware processor, or execution by a combination of hardware and software modules within the processor.

[0220] The memory may include high-speed RAM, and may also include non-volatile storage (NVM), such as at least one disk storage device, and may also be a USB flash drive, external hard drive, read-only memory, disk or optical disc, etc.

[0221] The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be categorized as address buses, data buses, control buses, etc. For ease of illustration, the buses shown in the accompanying drawings are not limited to a single bus or a single type of bus.

[0222] The aforementioned storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The storage medium can be any available medium that can be accessed by a general-purpose or special-purpose computer.

[0223] An exemplary storage medium is coupled to a processor, enabling the processor to read information from and write information to the storage medium. Alternatively, the storage medium can be an integral part of the processor. The processor and storage medium can reside in application-specific integrated circuits (ASICs). Alternatively, the processor and storage medium can exist as discrete components in an electronic control unit or main control device.

[0224] Those skilled in the art will understand that all or part of the steps of the above-described method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments; and the aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0225] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A harmonic compensation control method for an active filter, characterized in that, include: The grid-side voltage and grid-side current of a three-phase power system are collected; wherein, the three-phase power system is used to supply power to the power load system, the grid-side voltage represents the voltage at the connection point between the three-phase power system and the user incoming main cabinet in the power load system, and the grid-side current represents the current at the connection point between the three-phase power system and the user incoming main cabinet; Harmonic analysis is performed on the grid-side voltage and grid-side current to obtain the first harmonic analysis result of the grid-side voltage and the second harmonic analysis result of the grid-side current; based on the first harmonic analysis result and the second harmonic analysis result, a harmonic compensation control model is constructed for the active filter in the power load system; A preset algorithm is used to locally solve the harmonic compensation control model to determine the reference current of the active filter; the active filter is then controlled to output a harmonic compensation current that is the same as the reference current.

2. The method according to claim 1, characterized in that, The preset algorithm is the trust region projection gradient algorithm; The harmonic compensation control model is locally solved using a preset algorithm to determine the reference current of the active filter, including: The trust region projection gradient algorithm is used to locally solve the harmonic compensation control model to obtain the admittance coefficients of each harmonic; wherein, the admittance coefficients of each harmonic characterize the impedance characteristics of the three-phase power system at a preset harmonic frequency, and the preset harmonic frequency is a frequency that is a preset multiple of the standard fundamental frequency. Based on the admittance coefficients of each harmonic, the reference current components of each harmonic are calculated; based on the reference current components of each harmonic, the reference current of the active filter is generated.

3. The method according to claim 2, characterized in that, The trust region projection gradient algorithm is used to locally solve the harmonic compensation control model, including: The harmonic compensation control model is simulated based on a preset local quadratic model, and the preset local quadratic model is solved using the trust region projection gradient algorithm. In the process of solving the preset local quadratic model, the variable update direction of the preset local quadratic model indicated by the trust region projection gradient algorithm is determined, and the variable update direction is corrected to the feasible region of the harmonic compensation control model; and the trust region radius of the trust region projection gradient algorithm is dynamically adjusted. When the descent gradient of the trust region projection gradient algorithm satisfies the first preset condition, or when the number of iterations of the trust region projection gradient algorithm satisfies the second preset condition, the solution of the preset local quadratic model is stopped.

4. The method according to claim 1, characterized in that, The first harmonic analysis result includes the voltage harmonic components and the effective values ​​of each voltage harmonic component of the grid-side voltage; the second harmonic analysis result includes the current harmonic components and the effective values ​​of each current harmonic component of the grid-side current.

5. The method according to claim 4, characterized in that, Based on the first harmonic analysis results and the second harmonic analysis results, a harmonic compensation control model is constructed for the active filter in the power load system, including: Based on the effective values ​​of each voltage harmonic component and each current harmonic component, the apparent power of the three-phase power system is calculated. Determine the effective value of the target current harmonic component that is greater than the preset current threshold among the effective values ​​of each current harmonic component. A preset penalty term is set for the effective value of the target current harmonic component; and an optimization target is defined based on the apparent power and the preset penalty term; based on the optimization target, a harmonic compensation control model is constructed for the active filter in the power load system.

6. The method according to claim 5, characterized in that, The method further includes: Set voltage total harmonic distortion rate constraints, voltage single harmonic distortion rate constraints, and system power balance constraints for the harmonic compensation control model; The voltage total harmonic distortion rate constraint indicates that the total harmonic distortion rate of the grid-side voltage is less than or equal to a first preset threshold; the voltage single harmonic distortion rate constraint indicates that the distortion rate of each voltage harmonic component of the grid-side voltage is less than or equal to a second preset threshold; and the system power balance constraint indicates that the active power of the three-phase power system is in a preset balance state.

7. The method according to any one of claims 1 to 6, characterized in that, The method further includes: The load current of the three-phase power system is collected, and harmonic analysis is performed on the load current to determine the current harmonic components and effective values ​​of each current harmonic component; wherein, the load current represents the current flowing through the electrical terminals included in the power load system; The effective values ​​of the target current harmonic components that are greater than a preset current threshold are obtained from the effective values ​​of each current harmonic component of the grid-side current, as well as the target harmonic order and target current harmonic component corresponding to the effective values ​​of the target current harmonic components. The current harmonic components of each load current at the target harmonic order are matched with the target current harmonic components to determine the target load current corresponding to the current harmonic component that is successfully matched with the target current harmonic component. The power terminal corresponding to the target load current is determined, and the harmonic compensation current output by the active filter is injected into the power terminal.

8. A harmonic compensation control device for an active filter, characterized in that, include: The acquisition module is used to acquire the grid-side voltage and grid-side current of the three-phase power system; wherein, the three-phase power system is used to supply power to the power load system, the grid-side voltage represents the voltage at the connection point between the three-phase power system and the user incoming line cabinet in the power load system, and the grid-side current represents the current at the connection point between the three-phase power system and the user incoming line cabinet; The analysis module is used to perform harmonic analysis on the grid-side voltage and grid-side current to obtain the first harmonic analysis result of the grid-side voltage and the second harmonic analysis result of the grid-side current; A construction module is used to construct a harmonic compensation control model for an active filter in a power load system based on the first harmonic analysis results and the second harmonic analysis results. The solution module is used to perform local solution of the harmonic compensation control model using a preset algorithm to determine the reference current of the active filter; The control module is used to control the active filter to output a harmonic compensation current that is the same as the reference current.

9. An electronic device, characterized in that, include: A processor, and a memory communicatively connected to the processor; The memory stores computer-executed instructions; The processor executes computer execution instructions stored in the memory to implement the harmonic compensation control method for the active filter as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, which, when executed by a processor, are used to implement the harmonic compensation control method for an active filter as described in any one of claims 1 to 7.

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