Method and system for precise power decoupling and tracking control based on virtual oscillators

Abstract

The application belongs to the technical field of power decoupling and control, and discloses a precise power decoupling and tracking control method and system based on a virtual oscillator, which comprises the following steps: obtaining real-time values of output voltage and grid-connected current of an inverter, and estimating impedance values of a grid-connected line; calculating active power and reactive power of the inverter respectively, converting power decoupling and reactive tracking targets into a parameter optimization problem of a frequency domain transfer function, and solving optimal control parameters by using a loop shaping controller convex optimization technology; sending a difference between an actual value and a reference value of the active power and a difference between an actual value and a reference value of the reactive power into a virtual oscillator controller of a pre-loop shaping controller to obtain a real-time reference voltage signal; and sending the reference voltage signal into an inner loop control to obtain a real-time PWM control signal, so as to realize power decoupling and tracking control of the inverter. The application has good precise power decoupling and tracking control characteristics, and realizes fast, accurate and independent dynamic and static power control.

Description

Technical Field

[0001] This invention relates to the field of power decoupling and control technology, and in particular to a precise power decoupling and tracking control method and system based on a virtual oscillator. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] With the continuous increase in the penetration rate of renewable energy sources such as photovoltaics and wind power, the problem of weak grid instability caused by them is becoming increasingly prominent. A high proportion of renewable energy connected to the grid leads to a significant increase in line impedance, resulting in exacerbated voltage fluctuations at the grid connection point. Traditional grid-following control strategies, lacking independent voltage support capabilities, struggle to guarantee system stability. In contrast, grid-based control, by simulating the static characteristics of synchronous machines, can actively provide voltage and frequency support. Among these, the Andhopunov virtual oscillator has attracted considerable attention due to its advantages such as fast dynamic response, harmonic-free voltage output, and flexible power regulation.

[0004] However, existing virtual oscillator control faces two major technical bottlenecks: First, power control coupling is particularly prominent in medium- and low-voltage distribution network scenarios. Such networks exhibit high impedance ratios, causing traditional decoupling control mechanisms for active power-power angle and reactive power-voltage to fail. This coupling effect includes both limited power transmission capacity under steady-state conditions and power oscillation problems under dynamic conditions, seriously threatening the stable operation of the system. Second, reactive power tracking accuracy is insufficient. Existing solutions generally rely on the accurate identification of line impedance parameters, which limits their effectiveness in practical engineering applications.

[0005] Existing decoupling methods have significant limitations: In static power decoupling, although virtual power / virtual voltage frequency uses a rotating matrix for decoupling, it does not consider large power angle characteristics, resulting in incomplete decoupling. Virtual impedance and current compensation methods are limited by the measurement accuracy of the grid connection point voltage. The virtual inductance method introduces a voltage drop, which has a negative impact on the power decoupling effect. While QVPDC (q-axis decoupling control) can compensate for the voltage drop, it lacks adaptive operating point capability, resulting in poor dynamic decoupling performance. In dynamic power decoupling, the feedback compensation matrix method only compensates for the line impedance angle, and power coupling still occurs. The virtual inductor-capacitor method expands the range of virtual inductor selection, but it relies on the estimation of line impedance and is incomplete in its analysis of broadband power coupling. Furthermore, inaccurate reactive power tracking is widespread in grid-type control. Methods such as droop reference voltage correction and adaptive tracking are used to improve tracking accuracy, but their engineering practicality heavily depends on parameter sensitivity.

[0006] Therefore, it is of great significance to study a precise power decoupling and tracking control method based on a virtual oscillator grid-type inverter, which addresses the core issues of power coupling and reactive power inaccuracy in virtual oscillator control. Summary of the Invention

[0007] To address the aforementioned issues, this invention proposes a precise power decoupling and tracking control method and system based on a virtual oscillator, which possesses excellent precise power decoupling and tracking control characteristics, achieving fast, accurate, and independent dynamic and static power control.

[0008] To achieve the above objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides a precise power decoupling and tracking control method based on a virtual oscillator, comprising the following steps: Obtain the real-time values ​​of the inverter's output voltage and grid-connected current, and estimate the impedance value of the grid-connected line based on the obtained data; Based on the real-time values ​​of voltage and current, the active power and reactive power of the inverter are calculated respectively. The power decoupling and reactive power tracking objectives are transformed into parameter optimization problems of frequency domain transfer functions. The optimal control parameters are solved by using loop shaping controller convex optimization technology. The difference between the actual value of active power and the reference value, as well as the difference between the actual value of reactive power and the reference value, are sent to the virtual oscillation controller of the front-end loop shaping controller to obtain the real-time reference voltage signal. The reference voltage signal is sent to the inner loop control to obtain the real-time PWM control signal, thereby realizing the power decoupling and tracking control of the inverter.

[0009] As an alternative implementation, the power model is linearized using the small-signal modeling method to establish the inverter power flow. M and virtual oscillator K The small-signal model is as follows: ; ; In this context, the subscript 0 represents the steady-state equilibrium point. .

[0010] As an alternative implementation, power decoupling and reactive power tracking are transformed into a parameter optimization problem of the frequency domain transfer function, specifically: ; Here, || represents the 2-norm.

[0011] As an alternative implementation, the frequency range is discretized into a grid, transforming the convex semi-infinite programming problem into a convex semi-definite programming problem: .

[0012] As an alternative implementation method, the formulas for calculating the active power and reactive power of the inverter are as follows: ; in, v dq , i odq Output voltage v Grid-connected current i o The dq axis components.

[0013] As an alternative implementation, it also includes establishing a closed-loop transfer function matrix to analyze the broadband power coupling degree and reactive power tracking capability. This matrix is: .

[0014] Secondly, the present invention provides a precise power decoupling and tracking control system based on a virtual oscillator, comprising: The data acquisition module is configured to: acquire the real-time values ​​of the inverter's output voltage and grid-connected current, and estimate the impedance value of the grid-connected line based on the acquired data; The parameter solving module is configured to: calculate the active power and reactive power of the inverter based on the acquired real-time values ​​of voltage and current, convert the power decoupling and reactive power tracking target into a parameter optimization problem of frequency domain transfer function, and solve the optimal control parameters using loop shaping controller convex optimization technology; The reference voltage signal calculation module is configured to send the difference between the actual value of active power and the reference value, and the difference between the actual value of reactive power and the reference value, into the virtual oscillation controller of the front-end loop shaping controller to obtain the real-time reference voltage signal. The power decoupling and reactive power tracking data acquisition module is configured to send the reference voltage signal into the inner loop control to obtain a real-time PWM control signal, thereby realizing power decoupling and tracking control of the inverter.

[0015] Thirdly, the present invention provides an electronic device including a memory and a processor, and computer instructions stored in the memory and running on the processor, wherein the computer instructions, when executed by the processor, perform the method described in the first aspect.

[0016] Fourthly, the present invention provides a computer-readable storage medium for storing computer instructions, which, when executed by a processor, perform the method described in the first aspect.

[0017] Fifthly, the present invention provides a computer program product, including a computer program that, when executed by a processor, implements the method described in the first aspect.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention proposes a precise power decoupling and tracking control method based on a virtual oscillator. Utilizing an optimal loop shaping control strategy, it achieves precise decoupling control of active and reactive power, exhibiting good static and dynamic decoupling effects and fast response speed. The goal of power decoupling and reactive power tracking is transformed into a frequency domain transfer function design problem. Parameter selection is achieved using optimal convex optimization techniques, simultaneously realizing power decoupling and accurate reactive power tracking. Furthermore, the closed-loop transfer function matrix analysis method is extended. Diagonal elements are used to evaluate power tracking characteristics, while off-diagonal elements are used to analyze the degree of dynamic and static power coupling. This method verifies the excellent performance of the proposed strategy.

[0019] Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0020] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0021] Figure 1 The main circuit diagram and control block diagram of the grid-connected inverter based on the virtual oscillator are shown below. Figure 2 A simplified circuit diagram of the inverter system; Figure 3 Block diagram of the small-signal model of the inverter system; Figure 4 Bode plot analysis for power decoupling and reactive power tracking characteristics; Figure 5 This is a block diagram of the small-signal model of the inverter system under the optimal loop shaping method of the present invention; Figure 6 The diagram shows the theoretical analysis effect of the power decoupling characteristics of the optimal loop forming method of the present invention. Figure 7 The diagram shows the theoretical analysis effect of the reactive power tracking characteristics of the optimal loop forming method of the present invention. Figure 8 This is a comparison diagram of the output power waveforms of the optimal loop forming method of the present invention with those of the virtual inductance method and the QVPDC method. Detailed Implementation

[0022] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0023] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0024] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments of the invention. As used herein, unless the context clearly indicates otherwise, the singular form is intended to include the plural form as well. Furthermore, it should be understood that the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but includes other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0025] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0026] Example 1 This embodiment provides a precise power decoupling and tracking control method based on a virtual oscillator, including the following steps: Obtain the real-time values ​​of the inverter's output voltage and grid-connected current, and estimate the impedance value of the grid-connected line based on the obtained data; Based on the real-time values ​​of voltage and current, the active power and reactive power of the inverter are calculated respectively. The power decoupling and reactive power tracking objectives are transformed into parameter optimization problems of frequency domain transfer functions. The optimal control parameters are solved by using loop shaping controller convex optimization technology. The difference between the actual value of active power and the reference value, as well as the difference between the actual value of reactive power and the reference value, are sent to the virtual oscillation controller of the front-end loop shaping controller to obtain the real-time reference voltage signal. The reference voltage signal is sent to the inner loop control to obtain the real-time PWM control signal, thereby realizing the power decoupling and tracking control of the inverter.

[0027] The specific solution of the present invention is as follows: 1. Inverter Model and Power Control Analysis: 1.1 Small-signal model of inverter system: The control block diagram of the Andhopunov virtual oscillator is attached. Figure 1 As shown, the three-phase output voltage of the inverter is measured. v Three-phase grid-connected current i o and grid connection line impedance Z g ∠θ Based on the measurement of voltage and current, the real-time power output can be obtained as follows: (1); in, v dq , iodq Output voltage v Grid-connected current i o The dq axis components.

[0028] The model of the Andhopunov oscillator can be represented as: (2); in, V The output voltage amplitude of the virtual oscillator. V n This is the output voltage reference value. μ For convergence speed, k v , k i These are the voltage and current amplification factors. Q For inverter power output, Q r For reactive power reference, ω n This is the reference value for angular frequency. P For the active power output of the inverter, P r For active power reference, C For the virtual oscillator capacitor.

[0029] The inverter controlled by the virtual oscillator is assumed to be a voltage source, and the simplified system circuit is shown in the attached figure. Figure 2 As shown. At this point, the power output can be further expressed as: (3); in, V This is the effective value of the inverter output voltage. E This is the effective value of the grid voltage. θ The line impedance angle. δ The work angle can be expressed as , This represents the total line impedance.

[0030] The power flow equation (3) Jacobian matrix can be paired V and δ Differentiate to obtain inverter power flow M Small signal model: (4); In this context, the subscript 0 represents the steady-state equilibrium point.

[0031] Similarly, by linearizing the Andhopunov virtual oscillator with small signals and ignoring higher-order terms, a virtual oscillator can be obtained. K The small signal model is as follows: (5); in, .

[0032] Therefore, the overall small-signal model of the inverter controlled by the virtual oscillator can be derived from equations (4) and (5), and its block diagram is attached. Figure 3 As shown. This model qualitatively reveals the power coupling characteristics of the virtual oscillator control, where... M 12 , M 21 This is a power coupling path.

[0033] 1.2 Closed-loop transfer function matrix method and power control analysis: To quantitatively and accurately analyze the degree of power coupling and the inaccurate reactive power control of the virtual oscillator, the closed-loop transfer function method is applied to the control analysis of the virtual oscillator. A method for analyzing the closed-loop transfer function matrix is ​​proposed, and its specific derivation is as follows: (6); in, S ij To represent from the first i The input to the first j The sum of the products of the forward channels of each output and the remaining sub-expressions, where ∆ represents the characteristic expression of the flow graph, the closed-loop transfer function matrix can be expressed as: (7); Specifically, diagonal elements quantify the tracking performance of active and reactive power respectively, while off-diagonal elements evaluate the degree of power coupling. T 12 (s) When it approaches 0, the impact of reactive power on active power control can be ignored; similarly, small T 21 (s) indicates that the coupling degree of the active power reference in reactive power is the lowest. T 22 The fact that (s) is close to 1 indicates that the reactive power tracking accuracy is very high.

[0034] Typical control parameters are selected as shown in Table 1. Based on the small-signal model and closed-loop transfer function matrix analysis method, Bode plots (amplitude units are absolute values) are drawn for active power reference 0.2~1 pu and frequency variation 0~20 Hz, as shown in the appendix. Figure 4 As shown. By Figure 4 As known from (a) and (b), inverters controlled by virtual oscillators exhibit significant power coupling problems in both active and reactive power loops. Specifically, T 12 The value of 10Hz reaches its maximum value, indicating the degree of coupling between active power and reactive power. T21 The value of remains above 0.5 pu in the low-frequency range, indicating that changes in the active power reference will lead to significant reactive power coupling. Furthermore, due to... Figure 4 (c) It can be seen that the virtual oscillator cannot accurately track reactive power. T 22 The maximum value is 0.5 pu, which means that even at the best operating point, the reactive power can only track half of the command value.

[0035] Table 1. Main circuit parameters and control parameters of the virtual oscillator-controlled inverter system;

[0036] 2. Control objectives: The objective of precise power decoupling and tracking control can be transformed into the design problem of an ideal open-loop transfer function. Specifically, precise power decoupling requires that the off-diagonal elements of the ideal open-loop transfer function maintain the lowest possible loop gain over a wide frequency range, while accurate reactive power tracking requires that the diagonal elements include an integral term to achieve zero steady-state error reactive power tracking. Therefore, considering the closed-loop bandwidth characteristics (outer loop bandwidth is 1 / 10 to 1 / 5 of the inner loop bandwidth, and the switching frequency is 20 kHz), the ideal open-loop transfer function can be expressed as a 2*2 matrix: (8).

[0037] 3. Optimal Loop Shaping Power Controller: This invention presents an optimal loop shaping broadband control method for addressing the power coupling and reactive power misalignment problems in inverters controlled by virtual oscillators. Specifically, this decoupling strategy transforms power decoupling and accurate reactive power tracking into a frequency domain transfer function, and uses convex optimization theory to solve for the optimal loop shaping parameters to achieve the desired effect. This method optimizes parameters over a wide frequency range, achieves complete power decoupling control in steady state, exhibits minimal reactive power coupling fluctuations under dynamic conditions, achieves accurate reactive power tracking, and significantly accelerates the power control response speed of the virtual oscillator, demonstrating remarkable effectiveness.

[0038] 3.1 Optimal Loop Forming Control Design: Based on the small-signal model of the virtual oscillator, the power control transfer function matrix for two inputs and two outputs is given as follows: (9); Based on the internal model principle, accurate power point tracking requires an integral element in the controller. Therefore, a PI-based controller is selected, and the optimal loop shaping controller can be expressed as: (10); in, ; Transforming the above controller and power control transfer function matrix into the frequency domain yields: (11); Therefore, the problem of optimizing the conversion parameters of precise power decoupling and tracking control targets is... (12); Here, || represents the 2-norm.

[0039] Furthermore, the parameter optimization problem is transformed into the frequency domain: (13); Gershgorin's circle theorem and the Nyquist stability criterion are added as constraints during the parameter optimization process: (14); in, .

[0040] The optimization problem described above is a typical convex semi-infinite programming problem, where when At this time, the optimal objective and stability constraints must be strictly satisfied. To solve this problem, this paper discretizes the frequency range into a grid, effectively transforming the convex semi-infinite programming problem into a convex semi-definite programming problem: (15); in, .

[0041] After designing the parameters as described above, the optimal parameters are solved using YALMIP and MOSEK tools. Finally, the parameters, after discretization, can be expressed as: (16); in, .

[0042] According to the attached Figure 1 and attached Figure 5 By embedding the designed optimal circuit shaping power control into the virtual oscillator control in the small-to-medium signal model, precise power decoupling and tracking control characteristics can be achieved.

[0043] 3.2 Analysis of Wideband Power Control Effect: Similarly, a closed-loop transfer function matrix model of the inverter system after incorporating optimal loop shaping control is established to analyze the performance of precise power decoupling and tracking control. The derivation is as follows: (17); in, ; The control characteristics are analyzed by plotting the Bode plot of the closed-loop transfer function matrix after incorporating the proposed strategy, as shown in the attached figure. Figure 6 As shown. At this time, the off-diagonal elements T 12 and T 21 The transfer function amplitude remains below 0.074 pu over a wide frequency range and with varying active power reference values, indicating that the proposed method can achieve precise power decoupling control. Similarly, Figure 7 Drawn T 22 The Bode plot shows that its amplitude remains around 1 pu across a wide frequency range, indicating that the optimal loop shaping controller can not only achieve precise power decoupling but also effectively reshape reactive power control characteristics.

[0044] In the experiment, the effectiveness of the proposed strategy was verified by comparing the performance of three different decoupling methods in steady-state power decoupling, dynamic power decoupling, and accurate power tracking. Specific waveforms are shown in the attached figure. Figure 8 As shown.

[0045] Example 2 This embodiment provides a precise power decoupling and tracking control system based on a virtual oscillator, including: The data acquisition module is configured to: acquire the real-time values ​​of the inverter's output voltage and grid-connected current, and estimate the impedance value of the grid-connected line based on the acquired data; The parameter solving module is configured to: calculate the active power and reactive power of the inverter based on the acquired real-time values ​​of voltage and current, convert the power decoupling and reactive power tracking target into a parameter optimization problem of frequency domain transfer function, and solve the optimal control parameters using loop shaping controller convex optimization technology; The reference voltage signal calculation module is configured to send the difference between the actual value of active power and the reference value, and the difference between the actual value of reactive power and the reference value, into the virtual oscillation controller of the front-end loop shaping controller to obtain the real-time reference voltage signal. The power decoupling and reactive power tracking data acquisition module is configured to send the reference voltage signal into the inner loop control to obtain a real-time PWM control signal, thereby realizing power decoupling and tracking control of the inverter.

[0046] It should be noted that the above modules correspond to the steps in Embodiment 1, and the examples and application scenarios implemented by the above modules and their corresponding steps are the same, but are not limited to the content disclosed in Embodiment 1. It should also be noted that the above modules can be executed in a computer system as part of the system.

[0047] In further embodiments, the following is also provided: An electronic device includes a memory and a processor, as well as computer instructions stored in the memory and running on the processor, which, when executed by the processor, perform the method described in Embodiment 1. For brevity, further details are omitted here.

[0048] It should be understood that in this embodiment, the processor can be a central processing unit (CPU), or it can be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor can be a microprocessor or any conventional processor.

[0049] A computer-readable storage medium for storing computer instructions that, when executed by a processor, perform the method of Embodiment 1.

[0050] The method in Example 1 can be directly executed by a hardware processor, or it can be executed by a combination of hardware and software modules within the processor. The software modules can reside in readily available storage media in the art, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, or registers. This storage medium is located in memory; the processor reads information from the memory and, in conjunction with its hardware, completes the steps of the above method. To avoid repetition, a detailed description is not provided here.

[0051] A computer program product includes a computer program that, when executed by a processor, implements the method in Embodiment 1.

[0052] The present invention also provides at least one computer program product tangibly stored on a non-transitory computer-readable storage medium. The computer program product includes computer-executable instructions, such as instructions included in program modules, which execute in a device on a target real or virtual processor to perform the processes / methods described above. Typically, program modules include routines, programs, libraries, objects, classes, components, data structures, etc., that perform specific tasks or implement specific abstract data types. In various embodiments, the functionality of program modules can be combined or divided among program modules as needed. The machine-executable instructions for the program modules can execute within a local or distributed device. In a distributed device, the program modules can reside in both local and remote storage media.

[0053] The computer program code used to implement the methods of the present invention may be written in one or more programming languages. This computer program code may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when executed by the computer or other programmable data processing device, the program code causes the functions / operations specified in the flowcharts and / or block diagrams to be implemented. The program code may be executed entirely on a computer, partially on a computer, as a stand-alone software package, partially on a computer and partially on a remote computer, or entirely on a remote computer or server.

[0054] In the context of this invention, computer program code or related data may be carried by any suitable carrier to enable a device, apparatus, or processor to perform the various processes and operations described above. Examples of carriers include signals, computer-readable media, and the like. Examples of signals may include electrical, optical, radio, sound, or other forms of propagation signals, such as carrier waves, infrared signals, etc.

[0055] Those skilled in the art will recognize that the units and algorithm steps described in conjunction with the embodiments herein can be implemented in electronic hardware or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0056] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A precise power decoupling and tracking control method based on a virtual oscillator, characterized in that, Includes the following steps: Obtain the real-time values ​​of the inverter's output voltage and grid-connected current, and estimate the impedance value of the grid-connected line based on the obtained data; Based on the real-time values ​​of voltage and current, the active power and reactive power of the inverter are calculated respectively. The power decoupling and reactive power tracking objectives are transformed into parameter optimization problems of frequency domain transfer functions. The optimal control parameters are solved by using loop shaping controller convex optimization technology. The difference between the actual value of active power and the reference value, as well as the difference between the actual value of reactive power and the reference value, are sent to the virtual oscillation controller of the front-end loop shaping controller to obtain the real-time reference voltage signal. The reference voltage signal is sent into the inner loop control to obtain the real-time PWM control signal, thereby realizing the power decoupling and tracking control of the inverter; The power model is linearized using a small-signal modeling method to establish the inverter power flow. M and virtual oscillator K The small-signal model is as follows: ； ； In this context, the subscript 0 represents the steady-state equilibrium point. , V The output voltage amplitude of the virtual oscillator. E This is the effective value of the grid voltage. θ The line impedance angle. δ The work angle is represented as The total line impedance is Z g ∠θ , V n This is the output voltage reference value. μ For convergence speed, k v , k i These are the voltage and current amplification factors. Q For the reactive power output of the inverter, Q r For reactive power reference, P For the active power output of the inverter, C For virtual oscillator capacitors; The power decoupling and reactive power tracking problem is transformed into a parameter optimization problem of the frequency domain transfer function, specifically: Where |||2 represents the 2-norm; By discretizing the frequency range into a grid, the convex semi-infinite programming problem is transformed into a convex semi-definite programming problem: .

2. The precise power decoupling and tracking control method based on a virtual oscillator as described in claim 1, characterized in that, The formulas for calculating the active and reactive power of an inverter are as follows: ； in, v d , v q , i od , i oq Output voltage v Grid-connected current i o The dq axis components.

3. The precise power decoupling and tracking control method based on a virtual oscillator as described in claim 1, characterized in that, This also includes establishing a closed-loop transfer function matrix to analyze the broadband power coupling degree and reactive power tracking capability. The matrix is ​​as follows: In this model, diagonal elements quantify the tracking performance of active and reactive power, respectively, while off-diagonal elements evaluate the degree of power coupling. S ij To represent from the first i The input to the first j The sum of the products of the forward channels of each output and the remaining subexpressions. This represents the characteristic expression of the flow graph.

4. A precise power decoupling and tracking control system based on a virtual oscillator, characterized in that, include: The data acquisition module is configured to: acquire the real-time values ​​of the inverter's output voltage and grid-connected current, and estimate the impedance value of the grid-connected line based on the acquired data; The parameter solving module is configured to: calculate the active power and reactive power of the inverter based on the acquired real-time values ​​of voltage and current, convert the power decoupling and reactive power tracking target into a parameter optimization problem of frequency domain transfer function, and solve the optimal control parameters using loop shaping controller convex optimization technology; The reference voltage signal calculation module is configured to send the difference between the actual value of active power and the reference value, and the difference between the actual value of reactive power and the reference value, into the virtual oscillation controller of the front-end loop shaping controller to obtain the real-time reference voltage signal. The power decoupling and reactive power tracking data acquisition module is configured to: send the reference voltage signal into the inner loop control to obtain the real-time PWM control signal, thereby realizing power decoupling and tracking control of the inverter; The power model is linearized using a small-signal modeling method to establish the inverter power flow. M and virtual oscillator K The small-signal model is as follows: ； ； In this context, the subscript 0 represents the steady-state equilibrium point. , V The output voltage amplitude of the virtual oscillator. E This is the effective value of the grid voltage. θ The line impedance angle. δ The work angle is represented as The total line impedance is Z g ∠θ , V n This is the output voltage reference value. μ For convergence speed, k v , k i These are the voltage and current amplification factors. Q For the reactive power output of the inverter, Q r For reactive power reference, P For the active power output of the inverter, C For virtual oscillator capacitors; The power decoupling and reactive power tracking problem is transformed into a parameter optimization problem of the frequency domain transfer function, specifically: Where |||2 represents the 2-norm; By discretizing the frequency range into a grid, the convex semi-infinite programming problem is transformed into a convex semi-definite programming problem: .

5. An electronic device, characterized in that, It includes a memory and a processor, as well as computer instructions stored in the memory and running on the processor, which, when executed by the processor, perform the method according to any one of claims 1-3.

6. A computer-readable storage medium, characterized in that, Used to store computer instructions, which, when executed by a processor, perform the method described in any one of claims 1-3.

7. A computer program product, characterized in that, Includes a computer program, which, when executed by a processor, implements the method described in any one of claims 1-3.

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