High-reliability complex coefficient repetitive control grid-connected inverter control system and method suitable for power supply guarantee scene

Abstract

The invention discloses a high-reliability complex coefficient repetitive control grid-connected inverter control system and method suitable for a power supply protection scene, and the method comprises the steps: building an LCL type grid-connected inverter mathematical model under an alpha-beta static coordinate system for a three-phase grid-connected inverter, and saving Park transformation and decoupling calculation under a dq coordinate system; a complex coefficient filter H (s) and a complex coefficient repetitive controller are designed to form a double-input double-output control structure, and a complex coefficient imaginary part omega m is set to be equal to a fundamental frequency omega 0, so that the gain of the controller at the fundamental frequency is infinite, and complete tracking of periodic signals is realized; and the dynamic response capability of the system is improved by combining an output feedback control law. According to the method, the grid-side voltage imbalance and harmonic pollution can be effectively suppressed, the grid-connected current THD can be remarkably reduced, and the method has good dynamic control performance and robustness, is suitable for a grid-connected power generation system of new energy such as solar energy and wind energy, and plays an important supporting role in improving the power supply reliability and supply guarantee capability of a power system under the new energy access background.

Description

Technical Field

[0001] This invention relates to the fields of power electronics technology and new energy grid-connected control, specifically to a highly reliable complex coefficient repetitive control grid-connected inverter control system and method suitable for power supply guarantee scenarios. Background Technology

[0002] Solar and wind power, as emerging distributed generation units, have inherent limitations compared to traditional power generation, including issues such as islanding and harmonic pollution. Harmonic pollution is a problem that must be addressed when integrating new energy power generation into the grid. Distortions in grid-connected voltage and current waveforms can cause electromagnetic interference to power lines along their paths, and in severe cases, can seriously damage the safe and reliable operation of the power grid.

[0003] Currently, the control strategies of grid-connected inverters mainly include: (1) PI control based on the dq coordinate system, which requires Park transformation and decoupling calculation, and the model establishment is complicated; (2) traditional repetitive control, which uses real coefficient filters and cannot effectively handle the coupling components under the αβ coordinate system; (3) proportional resonance control, which has a good effect on suppressing specific harmonics, but it is difficult to suppress multiple harmonics at the same time.

[0004] Traditional repetitive controllers employ low-pass filters, sacrificing high-frequency tracking performance to ensure system stability. However, excessively large low-pass filter bandwidth amplifies measurement noise, while insufficient bandwidth negatively impacts harmonic suppression. Furthermore, traditional repetitive controllers are implemented in dq or abc coordinate systems, requiring complex coordinate transformations and increasing computational burden. Summary of the Invention

[0005] The purpose of this invention is to provide a highly reliable complex coefficient repetitive control grid-connected inverter control system and method suitable for power supply guarantee scenarios. This invention can simplify the grid-connected inverter control model while improving harmonic suppression capability and system robustness, so as to meet the new challenges posed by the high proportion of new energy access to the stable operation of the power system and power supply guarantee.

[0006] To achieve this objective, the present invention provides a high-reliability complex-coefficient repetitive control grid-connected inverter control system suitable for power supply security scenarios, comprising: The state-space model building module is used to build a state-space model characterizing the dynamic characteristics of the LCL three-phase grid-connected inverter based on the topology and circuit parameters of the LCL three-phase grid-connected inverter. The grid-connected three-phase current on the grid side of the LCL three-phase grid-connected inverter is obtained based on the state-space model of the LCL three-phase grid-connected inverter. The current error signal generation module is used to convert the grid-connected three-phase current into current components in the αβ coordinate system through Clarke transformation, to obtain α-axis current components and β-axis current components. The difference between the preset α-axis reference current and the α-axis current components is used as the α-axis error current, and the difference between the preset β-axis reference current and the β-axis current components is used as the β-axis error current. The complex coefficient repetitive control module is used to perform subtraction processing on the α-axis error current and β-axis error current of the current current control cycle and the α-axis compensation voltage control quantity and β-axis compensation voltage control quantity obtained by the complex coefficient filter of the previous current control cycle to obtain the intermediate state α-axis compensation voltage control quantity and intermediate state β-axis compensation voltage control quantity. The complex coefficient filter is then used to filter the intermediate state α-axis compensation voltage control quantity and intermediate β-axis compensation voltage control quantity to obtain the α-axis compensation voltage control quantity and β-axis compensation voltage control quantity of the current current control cycle. The control voltage acquisition module is used to obtain the α-axis voltage control quantity and the β-axis voltage control quantity based on the pre-calibrated composite cooperative control law, α-axis current component, β-axis current component, α-axis compensation voltage control quantity of the current current control cycle, and β-axis compensation voltage control quantity of the current current control cycle. The modulation signal conversion module is used to convert the α-axis voltage control quantity and β-axis voltage control quantity into a three-phase modulated voltage signal through Clarke inverse transformation, and to generate the drive signal of the LCL type three-phase grid-connected inverter through the three-phase modulated voltage signal and the space vector pulse width modulation method.

[0007] Furthermore, based on the topology and circuit parameters of the LCL-type three-phase grid-connected inverter, a state-space model characterizing the dynamic characteristics of the LCL-type three-phase grid-connected inverter is established in the αβ stationary coordinate system. Methods for obtaining the grid-connected three-phase current on the grid side of the LCL-type three-phase grid-connected inverter based on the state-space model include: ; in, Let m be the state vector, T be the transpose operator, and m = a, b, c. This refers to the phase a current on the inverter side of an LCL-type three-phase grid-connected inverter. This refers to the b-phase current on the inverter side of an LCL-type three-phase grid-connected inverter. This refers to the c-phase current on the inverter side of an LCL-type three-phase grid-connected inverter. This refers to the phase a capacitor voltage of an LCL-type three-phase grid-connected inverter. This refers to the voltage of the b-phase capacitor in an LCL-type three-phase grid-connected inverter. This refers to the voltage of the c-phase capacitor in an LCL-type three-phase grid-connected inverter. This refers to the phase a current on the grid side of the LCL-type three-phase grid-connected inverter. This refers to the phase b current on the grid side of the LCL-type three-phase grid-connected inverter. This refers to the c-phase current on the grid side of the LCL-type three-phase grid-connected inverter. For the input vector, This refers to the output voltage of phase a of the LCL-type three-phase grid-connected inverter. This refers to the output voltage of phase b of the LCL-type three-phase grid-connected inverter. This refers to the output voltage of the C-phase bridge arm of the LCL-type three-phase grid-connected inverter. Let A be the disturbance vector containing the grid voltage term, B be the system matrix containing inductance, capacitance, and parasitic resistance parameters, C be the input matrix determined by the inverter-side inductance, and D be the grid-side current output matrix of the LCL-type three-phase grid-connected inverter. This refers to the grid-connected three-phase current on the grid side of the LCL-type three-phase grid-connected inverter.

[0008] Furthermore, the method for converting the grid-connected three-phase current into current components in the αβ coordinate system using Clarke transformation to obtain the α-axis current component and β-axis current component includes: , ; in, Let α be the α-axis current component in the αβ coordinate system. The β-axis current component in the αβ coordinate system. This refers to the phase a current on the grid side of the LCL-type three-phase grid-connected inverter. This refers to the phase b current on the grid side of the LCL-type three-phase grid-connected inverter. This refers to the c-phase current on the grid side of the LCL-type three-phase grid-connected inverter.

[0009] Furthermore, based on the α-axis error current and β-axis error current of the current current control cycle and the α-axis compensation voltage control quantity and β-axis compensation voltage control quantity obtained from the complex coefficient filter of the previous current control cycle, the difference is processed to obtain the intermediate α-axis compensation voltage control quantity and intermediate β-axis compensation voltage control quantity. The intermediate α-axis compensation voltage control quantity and intermediate β-axis compensation voltage control quantity are then filtered using a complex coefficient filter to obtain the α-axis compensation voltage control quantity and β-axis compensation voltage control quantity of the current current control cycle. The methods include: ; ; ; in, For the complex coefficient repetitive controller at time t, the intermediate calculated variable represents the difference signal generated after comparing the current period error with historical memory information. For the α-axis error current, For the β-axis error current, for The intermediate state α-axis compensation voltage control quantity at time t. for The intermediate state β-axis compensation voltage control quantity at time t. Let be the intermediate state α-axis compensation voltage control quantity at time t. Let be the intermediate state β-axis compensation voltage control quantity at time t. Let be the α-axis compensation voltage control quantity at time t. Let be the β-axis compensation voltage control quantity at time t. Let be the transfer function of the complex coefficient filter. For the current control cycle, This is the output voltage control signal for the complex coefficient repetitive controller.

[0010] Furthermore, the transfer function of the complex coefficient filter is: ; The α-axis compensation voltage control quantity at time t As the real part of the complex signal, the β-axis compensation voltage at time t is controlled. To construct the imaginary part of the complex signal, then ,right Performing a Laplace transform on both sides of the equation, we get... , Will Substitution get: ; United and get: ; right Performing the inverse Laplace transform yields the differential equation for the complex coefficient filter, which is used to solve for the α-axis compensation voltage control quantity. β-axis compensation voltage control quantity : ; Where ωc is the filter cutoff frequency. Here, ω is the imaginary part parameter, and ω0 is the fundamental angular frequency of the power grid. For complex variables, The imaginary unit, For Hilbert transform, for Laplace transform, for Laplace transform, for Laplace transform, for Laplace transform, Let be the intermediate state α-axis compensation voltage control quantity at time t. Let be the intermediate state β-axis compensation voltage control quantity at time t. Let be the α-axis compensation voltage control quantity at time t. Let be the β-axis compensation voltage control quantity at time t. Let be the first derivative of the intermediate state α-axis compensation voltage control quantity at time t. It is the first derivative of the intermediate state β-axis compensation voltage control quantity at time t.

[0011] Furthermore, the method for obtaining the pre-calibrated composite cooperative control law includes: using the state-space model of the LCL-type three-phase grid-connected inverter, a complex coefficient repetitive controller, and the composite cooperative control law to form a complex coefficient repetitive control system; using Lyapunov stability theory as constraints, and solving the linear matrix inequality (LMI) to obtain the repetitive control gain matrix Ke and the output feedback gain matrix KP that satisfy the Lyapunov stability theory for the complex coefficient repetitive control system, thereby obtaining the pre-calibrated composite cooperative control law. , ; in, For repetitive control gain matrix, For the output feedback gain matrix, The output voltage control signal is for the complex coefficient repetitive controller. This represents the current components of the grid-connected three-phase current on the grid side of the LCL-type three-phase grid-connected inverter in the αβ coordinate system. Let α be the α-axis current component in the αβ coordinate system. The β-axis current component in the αβ coordinate system. This is the final voltage control value.

[0012] Furthermore, the method for obtaining the α-axis voltage control quantity and β-axis voltage control quantity based on the pre-calibrated composite cooperative control law, α-axis current component, β-axis current component, α-axis compensation voltage control quantity of the current current control cycle, and β-axis compensation voltage control quantity of the current current control cycle includes: in, This is the voltage control quantity for the α-axis. This is the β-axis voltage control quantity. Let be the α-axis compensation voltage control quantity at time t. Let be the β-axis compensation voltage control quantity at time t. For repetitive control gain matrix, For the output feedback gain matrix, For the α-axis current component, This represents the β-axis current component.

[0013] Furthermore, the method for converting the α-axis voltage control quantity and β-axis voltage control quantity into a three-phase modulated voltage signal through Clarke inverse transform, and then generating the drive signal for the LCL-type three-phase grid-connected inverter using the three-phase modulated voltage signal and space vector pulse width modulation method includes: The α-axis voltage control quantity and β-axis voltage control quantity are converted into a three-phase modulated voltage signal using the following Clarke inverse transform: ; in, This is the real-time α-axis voltage control quantity. This is the real-time β-axis voltage control quantity. The voltage signal is modulated by phase a. This is a phase b modulated voltage signal. This is a c-phase modulated voltage signal; Using the SVPWM algorithm , , It is converted into six PWM drive signals to drive the IGBT switches.

[0014] Furthermore, a highly reliable complex-coefficient repetitive control grid-connected inverter control method based on the system, suitable for power supply security scenarios, includes: Based on the topology and circuit parameters of the LCL three-phase grid-connected inverter, a state-space model characterizing the dynamic characteristics of the LCL three-phase grid-connected inverter is established. The grid-connected three-phase current on the grid side of the LCL three-phase grid-connected inverter is obtained based on the state-space model of the LCL three-phase grid-connected inverter. The grid-connected three-phase current is converted into current components in the αβ coordinate system through Clarke transformation to obtain α-axis current components and β-axis current components. The difference between the preset α-axis reference current and the α-axis current components is taken as the α-axis error current, and the difference between the preset β-axis reference current and the β-axis current components is taken as the β-axis error current. Based on the α-axis error current and β-axis error current of the current current control cycle, as well as the α-axis compensation voltage control quantity and β-axis compensation voltage control quantity obtained from the complex coefficient filter of the previous current control cycle, the difference is processed to obtain the intermediate α-axis compensation voltage control quantity and intermediate β-axis compensation voltage control quantity. The intermediate α-axis compensation voltage control quantity and intermediate β-axis compensation voltage control quantity are then filtered using a complex coefficient filter to obtain the α-axis compensation voltage control quantity and β-axis compensation voltage control quantity of the current current control cycle. The α-axis voltage control quantity and β-axis voltage control quantity are obtained based on the pre-calibrated composite cooperative control law, α-axis current component, β-axis current component, α-axis compensation voltage control quantity of the current current control cycle, and β-axis compensation voltage control quantity of the current current control cycle. The α-axis voltage control quantity and β-axis voltage control quantity are converted into a three-phase modulated voltage signal through Clarke inverse transformation, and the drive signal of the LCL type three-phase grid-connected inverter is generated by the three-phase modulated voltage signal and the space vector pulse width modulation method.

[0015] The beneficial effects of this invention are: (1) The control system is simplified: control is performed directly in the αβ coordinate system, eliminating the Park transformation and decoupling calculation in the dq coordinate system, thus reducing the computational complexity and implementation difficulty.

[0016] (2) Improved harmonic suppression capability: The complex coefficient repetitive controller has infinite gain at the fundamental frequency, which can completely track the fundamental signal; it also has a good suppression effect on harmonic components, significantly reducing the grid-connected current THD. Simulation results show that the peak-to-peak tracking error is only 49.12% of that of the traditional repetitive control method.

[0017] (3) Enhanced system robustness: The complex coefficient filter can effectively handle the coupling components in the αβ coordinate system and has a strong ability to suppress disturbances such as grid voltage imbalance and frequency fluctuation, thus improving the robustness of the system.

[0018] (4) Improved dynamic performance: Combined with the output feedback control law, the dynamic response speed of the system is improved, which can quickly track the changes of the reference signal and adapt to the changes of the power grid operating conditions. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the main circuit structure of an LCL-type three-phase grid-connected inverter. Figure 2 Block diagram for implementing complex coefficient filter H(s); Figure 3 This is a diagram of a complex coefficient repetitive controller with two inputs and two outputs. Figure 4 This is a diagram of the overall control system structure. Figure 5 Construction diagram for complex coefficient repetition control module; Figure 6 A comparison chart of simulation errors between traditional repetitive control (RC) and complex coefficient repetitive control (CRC); Figure 7 This is a schematic diagram of the structure of the present invention. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to represent selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0021] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments: Example 1 like Figure 7 As shown, a high-reliability complex-coefficient repetitive control grid-connected inverter control system suitable for power supply security scenarios includes: The state-space model building module is used to build a state-space model characterizing the dynamic characteristics of the LCL three-phase grid-connected inverter based on the topology and circuit parameters of the LCL three-phase grid-connected inverter. The grid-connected three-phase current on the grid side of the LCL three-phase grid-connected inverter is obtained based on the state-space model of the LCL three-phase grid-connected inverter. The current error signal generation module is used to convert the grid-connected three-phase current into current components in the αβ coordinate system through Clarke transformation, to obtain α-axis current components and β-axis current components. The difference between the preset α-axis reference current and the α-axis current components is used as the α-axis error current, and the difference between the preset β-axis reference current and the β-axis current components is used as the β-axis error current. The complex coefficient repetitive control module is used to perform subtraction processing on the α-axis error current and β-axis error current of the current current control cycle and the α-axis compensation voltage control quantity and β-axis compensation voltage control quantity obtained by the complex coefficient filter of the previous current control cycle to obtain the intermediate state α-axis compensation voltage control quantity and intermediate state β-axis compensation voltage control quantity. The complex coefficient filter is then used to filter the intermediate state α-axis compensation voltage control quantity and intermediate β-axis compensation voltage control quantity to obtain the α-axis compensation voltage control quantity and β-axis compensation voltage control quantity of the current current control cycle. The control voltage acquisition module is used to obtain the α-axis voltage control quantity and the β-axis voltage control quantity based on the pre-calibrated composite cooperative control law, α-axis current component, β-axis current component, α-axis compensation voltage control quantity of the current current control cycle, and β-axis compensation voltage control quantity of the current current control cycle. The modulation signal conversion module is used to convert the α-axis voltage control quantity and β-axis voltage control quantity into a three-phase modulated voltage signal through Clarke inverse transformation, and to generate the drive signal of the LCL type three-phase grid-connected inverter through the three-phase modulated voltage signal and the space vector pulse width modulation method.

[0022] In the αβ stationary coordinate system, the three-phase sinusoidal alternating current is combined into a counterclockwise rotating voltage / current vector. The α-axis current component and the β-axis current component are the instantaneous projections of this rotating vector onto the two perpendicular coordinate axes (α-axis and β-axis).

[0023] In some embodiments, such as Figure 1 As shown, the main circuit of the LCL type three-phase grid-connected inverter includes: DC bus voltage U dc DC bus capacitor C, inverter-side inductor L1, grid-side inductor L2, filter capacitor C f Six IGBT switches S1~S6. The three-phase bridge arm output voltage is u. a u b u c The inverter-side current is i 1a i 1b i 1c The grid-side current is i 2a i 2b i 2c The capacitor voltage is u ca u cb u cc The phase voltage of the power grid is u ga u gb u gcThe LCL (Liquid Crystal Array) three-phase grid-connected inverter topology converts the high-voltage DC-side (DC bus) current into AC power via a three-phase bridge inverter. This AC power is then filtered by an LCL filter (containing grid-side inductors, filter capacitors, and grid-side inductors) before being connected to the three-phase grid, achieving high-quality grid connection. The LCL topology defines the types of components in the circuit (such as DC bus capacitors and inverter-side inductors) and how these components are connected. Based on the LCL topology, input voltage and current, output voltage and current, DC bus voltage Udc, DC bus capacitor C, inverter-side inductor L1, grid-side inductor L2, and filter capacitor Cf can be obtained. Therefore, a state-space model characterizing the dynamic characteristics of the LCL three-phase grid-connected inverter can be established based on its topology and circuit parameters. The current power supply faces the critical challenge of high-proportion renewable energy grid integration. Renewable energy sources such as photovoltaics and wind power rely on grid-connected inverters to connect to the grid, and the control accuracy of these inverters directly affects grid connection stability and power quality, thus impacting the continuity of power supply. Existing control methods are prone to grid-connected current tracking errors, which may cause grid fluctuations and affect power supply security. To address this, this patent proposes a grid-connected inverter control strategy based on complex coefficient repetitive control. This strategy simplifies design, ensures system stability, reduces current tracking errors, and improves the adaptability of renewable energy grid connection, providing technical support for the safe operation and continuous power supply of the power system and contributing to the construction of a highly reliable new power system.

[0024] In some technical solutions, a state-space model characterizing the dynamic characteristics of an LCL-type three-phase grid-connected inverter is established based on the topology and circuit parameters of the inverter. Methods for obtaining the grid-connected three-phase current on the grid side of the LCL-type three-phase grid-connected inverter from this state-space model include: ; in, Let m be the state vector, T be the transpose operator, and m = a, b, c. This refers to the phase a current on the inverter side of an LCL-type three-phase grid-connected inverter. This refers to the b-phase current on the inverter side of an LCL-type three-phase grid-connected inverter. This refers to the c-phase current on the inverter side of an LCL-type three-phase grid-connected inverter. This refers to the phase a capacitor voltage of an LCL-type three-phase grid-connected inverter. This refers to the voltage of the b-phase capacitor in an LCL-type three-phase grid-connected inverter. This refers to the voltage of the c-phase capacitor in an LCL-type three-phase grid-connected inverter. This refers to the phase a current on the grid side of the LCL-type three-phase grid-connected inverter. This refers to the phase b current on the grid side of the LCL-type three-phase grid-connected inverter. This refers to the c-phase current on the grid side of the LCL-type three-phase grid-connected inverter. For the input vector, This refers to the output voltage of phase a of the LCL-type three-phase grid-connected inverter. This refers to the output voltage of phase b of the LCL-type three-phase grid-connected inverter. This refers to the output voltage of the C-phase bridge arm of the LCL-type three-phase grid-connected inverter. Let A be the disturbance vector containing the grid voltage term, B be the system matrix containing inductance, capacitance, and parasitic resistance parameters, C be the input matrix determined by the inverter-side inductance, and D be the grid-side current output matrix of the LCL-type three-phase grid-connected inverter. This refers to the grid-connected three-phase current on the grid side of the LCL-type three-phase grid-connected inverter.

[0025] By establishing a state-space model of an LCL-type three-phase grid-connected inverter, the physical topology and dynamic characteristics of the inverter can be transformed into mathematical expressions that are easy to observe and calculate. This provides a data foundation for the analysis and design of grid-connected inverter control strategies and allows for direct output matrix analysis. The grid-connected three-phase current is obtained from the grid side and used to achieve high-performance current closed-loop control.

[0026] In some technical solutions, the method for converting the grid-connected three-phase current into current components in the αβ coordinate system through Clarke transformation to obtain the α-axis current component and β-axis current component includes: , ; in, Let α be the α-axis current component in the αβ coordinate system. The β-axis current component in the αβ coordinate system. This refers to the phase a current on the grid side of the LCL-type three-phase grid-connected inverter. This refers to the phase b current on the grid side of the LCL-type three-phase grid-connected inverter. This refers to the c-phase current on the grid side of the LCL-type three-phase grid-connected inverter.

[0027] The AC current signal in the three-phase stationary coordinate system is converted into a DC signal in the two-phase stationary coordinate system, and the current is directly controlled in the αβ coordinate system. This eliminates the Park transformation and decoupling calculation in the dq coordinate system, reduces the complexity of current calculation and implementation difficulty, and provides instantaneous and accurate current data for subsequent current control.

[0028] In some technical solutions, the intermediate-state α-axis compensation voltage control quantity and intermediate-state β-axis compensation voltage control quantity are obtained by subtracting the α-axis error current and β-axis error current of the current current control cycle and the α-axis compensation voltage control quantity obtained by the complex coefficient filter of the previous current control cycle. The intermediate-state α-axis compensation voltage control quantity and intermediate-state β-axis compensation voltage control quantity are then filtered using a complex coefficient filter to obtain the α-axis compensation voltage control quantity and β-axis compensation voltage control quantity of the current current control cycle. ; ; ; in For the complex coefficient repetitive controller at time t, the intermediate calculated variable represents the difference signal generated after comparing the current period error with historical memory information. For the α-axis error current, For the β-axis error current, for The intermediate state α-axis compensation voltage control quantity at time t. for The intermediate state β-axis compensation voltage control quantity at time t. Let be the intermediate state α-axis compensation voltage control quantity at time t. Let be the intermediate state β-axis compensation voltage control quantity at time t. Let be the α-axis compensation voltage control quantity at time t. Let be the β-axis compensation voltage control quantity at time t. Let be the transfer function of the complex coefficient filter, and T be the current control period. The output voltage control signal is provided by the complex coefficient repetitive controller. The above calculation process is all completed by the complex coefficient repetitive controller. The current control cycle of the complex coefficient repetitive controller is extremely short (including but not limited to 50 microseconds per cycle). The current current control cycle corresponds to the cycle at time t, and time tT is the previous current control cycle. e α =I αref -I α e β =I βref -I β I αref The preset α-axis reference current (sine wave), I βref The preset β-axis reference current (sine wave signal).

[0029] In some embodiments, such as Figure 3 As shown, the complex coefficient repetitive controller adopts a dual-input dual-output structure. The input is the current error e in the αβ coordinate system. α e β The output is a control quantity. The controller contains a time delay element e. -Ts ,in (For a 50Hz power grid). Its input current error signal e α e β The error signal is first delayed by one period e -Ts Controller output status and The difference between the two signals is used as the input to the complex coefficient filter H(s). The complex coefficient filter adopts a dual-channel coupling structure, and the cross-coupling and decoupling processing between the α-axis and β-axis current signals is achieved through the ±ω0 terms to obtain the processed internal state. and , and On one hand, it is sent back to the periodic delay stage for storage and used in the calculation of the next current control cycle; on the other hand, it is calculated by a complex coefficient filter. and As the controller output for the current cycle.

[0030] Figure 5 The core structure of the complex coefficient repetitive controller is shown, and its technical content is embodied in a dual-channel estimation system with symmetrical cross-coupling. The input signal is shown at the top of the figure. and the input signal at the bottom These represent the two inputs to the control system in the αβ coordinate system (such as preprocessed error signals). Input signals First, compare it with the previous period value after a pure time delay cycle e-Ts. Subtracting these two values ​​yields the error for the current cycle; this error, multiplied by the gain coefficient ωc, is then compared with a feedback signal that has undergone the same delay and is multiplied by the cross-gain coefficient ω0. Add them together to get the signal. The data is then fed into the integrator s⁻¹I, which outputs the updated value for the current period. Input signal With delayed feedback After subtraction, multiply the error by the gain ωc, and then multiply it by the cross-feedback signal. Adding them together gives the signal The updated value for the current period is then fed into the integrator s-1I. Updated estimate and The signals are then fed back into their respective delay circuits e-Ts to provide feedback signals for the next control cycle. and This forms a closed-loop learning system with cyclical memory function.

[0031] In some technical solutions, the transfer function of the complex coefficient filter is: ; The α-axis compensation voltage control quantity at time t As the real part of the complex signal, the β-axis compensation voltage at time t is controlled. As the imaginary part of a complex signal, then ,right Performing a Laplace transform on both sides of the equation, we get... , Will Substitution get: ; United and get: ; right Performing the inverse Laplace transform yields the differential equation for the complex coefficient filter, which is used to solve for the α-axis compensation voltage control quantity. β-axis compensation voltage control quantity : ; Where ωc is the filter cutoff frequency. ω is the imaginary part parameter. 0 The fundamental angular frequency of the power grid. For complex variables, The imaginary unit, For Hilbert transform, for Laplace transform, for Laplace transform, for Laplace transform, for Laplace transform, Let be the intermediate state α-axis compensation voltage control quantity at time t. Let be the intermediate state β-axis compensation voltage control quantity at time t. Let be the α-axis compensation voltage control quantity at time t. Let be the β-axis compensation voltage control quantity at time t. Let be the first derivative of the intermediate state α-axis compensation voltage control quantity at time t. It is the first derivative of the intermediate state β-axis compensation voltage control quantity at time t.

[0032] In this invention, ωm is set to ω0. Since ωm = ω0, at the fundamental frequency ω = ω0, jω0 is substituted into the transfer function of the complex coefficient repetitive controller. And according to Euler's formula We can obtain: because =1、 If = 0, then the frequency domain gain of the complex coefficient repetitive controller is: ; This means the controller can completely eliminate the steady-state error at the fundamental frequency. For the kth harmonic (k=2,3,4,...), the controller gain is: As the harmonic order k increases, the controller gain gradually decreases, but remains at a high level, effectively suppressing low-order harmonics.

[0033] like Figure 2 As shown, the complex coefficient filter employs a dual-channel coupled structure, containing two parallel signal processing channels corresponding to the α and β axes, respectively. Each channel's core consists of a proportional element ωc, an integrator 1 / s, and local negative feedback. The two channels are connected via a cross-coupling term ±ω0, ensuring that the integrator output of one channel, after being boosted by ω0, is injected as a coupling quantity into the summation point of the other channel. The input to the complex coefficient filter is two signals. and The output consists of two state variables. and The integrator 1 / s of the complex coefficient filter ensures that the grid-connected inverter control system has infinite open-loop gain in steady state. Combined with a repetitive control structure, this enables the grid-connected inverter control system to achieve zero steady-state error tracking at the fundamental frequency ω0. The cross-positive / negative feedback formed by ω0 between the two channels allows the filter to generate a "rotating" pole with respect to frequency ω0 in the complex frequency domain, decoupling the positive and negative sequence components of the grid current in the αβ stationary coordinate system. This simplifies the controller design and improves the system's control performance under non-ideal grid conditions.

[0034] In some technical solutions, methods for obtaining the pre-calibrated composite cooperative control law include: using the state-space model of an LCL-type three-phase grid-connected inverter, a complex coefficient repetitive controller, and the composite cooperative control law to form a complex coefficient repetitive control system; using Lyapunov stability theory as constraints, solving the linear matrix inequality (LMI) to obtain the repetitive control gain matrix Ke and the output feedback gain matrix KP that satisfy Lyapunov stability theory for the complex coefficient repetitive control system; and then obtaining the pre-calibrated composite cooperative control law. , ; in, For repetitive control gain matrix, For the output feedback gain matrix, The output voltage control signal is for the complex coefficient repetitive controller. This represents the current components of the grid-connected three-phase current on the grid side of the LCL-type three-phase grid-connected inverter in the αβ coordinate system. Let α be the α-axis current component in the αβ coordinate system. The β-axis current component in the αβ coordinate system. This is the final voltage control value.

[0035] The composite cooperative control law combines repetitive control output based on the internal model principle with fast-response proportional feedback output. It uses repetitive control components to eliminate periodic tracking errors to ensure ultimate steady-state accuracy, while using proportional feedback components to provide error compensation to ensure the system's dynamic response speed. Together, they achieve high-precision and high-dynamic-performance tracking response of grid-connected current to control command signals.

[0036] like Figure 4 As shown, the grid-connected inverter control system is a typical closed-loop control system, consisting of three main parts: the forward channel, the controlled object, and the feedback channel. The forward channel (complex coefficient repetitive controller) sends the error signal e(t) generated by comparing the reference current Iref(t) with the feedback current y(t) to the complex coefficient repetitive controller. The complex coefficient repetitive controller contains a time-delay element e. -Ts The internal model positive feedback loop of the complex coefficient filter H(s) enables the "learning" and compensation of periodic errors, and the output of the complex coefficient repetitive controller... Multiplying with the repetitive control gain matrix Ke yields the repetitive control gain value; the controlled object: u(t) is the final voltage control quantity, acting on the controlled object (LCL type three-phase grid-connected inverter). The LCL type three-phase grid-connected inverter is modeled as an LCL type three-phase grid-connected inverter state-space model. In the LCL type three-phase grid-connected inverter state-space model... Let A be the state vector, B be the system matrix containing inductance, capacitance, and parasitic resistance parameters, C be the input matrix determined by the inverter-side inductance, and D be the grid-side current output matrix of the LCL three-phase grid-connected inverter. The derivative of the state vector is obtained through the integrator ∫_{-1} ... Integral calculations are performed to continuously update the state vector x(t). y(t) represents the actual output three-phase current of the LCL three-phase grid-connected inverter. Feedback channel: The actual output y(t) of the LCL three-phase grid-connected inverter is acquired in real time. y(t) is fed back and compared with the reference command Iref(t) to form a closed-loop feedback control, enabling the system to automatically correct deviations. It is also compared with the output feedback gain matrix. Multiplying these values ​​yields the output feedback gain, and the sum of the output feedback gain and the repetitive control gain is u(t).

[0037] In some embodiments, the method for calculating the repetitive control gain matrix Ke and output feedback gain matrix KP that satisfy the Lyapunov stability theory for the complex coefficient repetitive control system, using the linear matrix inequality (LMI) as constraints, includes: Since the stability of a linear system is independent of external disturbances, to analyze system stability, the reference signals r(t) = 0 and eg(t) = 0 can be set. Based on the state-space equation, the structure of the complex coefficient repetitive controller, and the control law, the complex coefficient repetitive control system can be expressed as: ; in, This is the Clark inverse transformation matrix. The derivative of the state vector. , ,in, The derivative of the intermediate variable for the complex coefficient repetitive controller at time t is calculated. The intermediate state α-axis compensation voltage control quantity at time t The derivative of The intermediate state β-axis compensation voltage control quantity at time t The derivative of .

[0038] , Given the filter coefficient matrix, the extended state vector is defined as follows: ,in, To extend the vector, It is the transpose of the state vector. This is the transpose of the intermediate computational variables of the complex coefficient repetitive controller at time t. Let T be the transpose vector of the derivative of the intermediate computed variable of the coefficient repetitive controller at time t, where T is the transpose operator.

[0039] The system can then be transformed into: ; An identity matrix with all elements as 1 on the main diagonal. The intermediate calculation variables of the filtered complex coefficient repetitive controller at time t.

[0040] In short: in The complex coefficient repetitive control grid-connected inverter control system is a time-delay system with lag, and its stability condition is given by the following theorem: For a given positive scalar a1, a2, a3, a4, a5, If there exist positive definite matrices P1, P2, P3, P4, P5, Q1, Q2, Q3, Q4, Q5, and suitable-dimensional matrices W1, W2, and suitable-dimensional positive definite matrix W3 such that the following linear matrix inequality holds, these two gain matrices are determined by solving the following linear matrix inequality LMI: ; Where P is the first positive definite matrix and Q is the second positive definite matrix. For the first system parameter matrix, This is the second system parameter matrix. Let be the transpose of the upper triangular part of the matrix, such that the linear matrix inequality LMI is a symmetric matrix.

[0041] ; in, These are the parameters in the first row and first column of the first system parameter matrix. These are the parameters in the second row and third column of the first system parameter matrix. These are the parameters in the second row and second column of the first system parameter matrix. The first parameter of the first positive definite matrix The second parameter of the first positive definite matrix The third parameter of the first positive definite matrix, The first parameter of the second positive definite matrix is... The second parameter of the second positive definite matrix The third parameter of the second positive definite matrix, This is the transpose of the grid-side current output matrix of an LCL-type three-phase grid-connected inverter. This is the Clarke inverse transform matrix. This is the transpose of the Clarke inverse transform matrix.

[0042] The complex coefficient repetitive control system is asymptotically stable, and the output feedback gain matrix is... Repetitive control gain matrix It is designed from the following formula: in, The first auxiliary matrix obtained by solving LMI, The second auxiliary matrix obtained by solving LMI, The second auxiliary matrix obtained by solving LMI, This is the first adjustment parameter. This is the third adjustment parameter.

[0043] In some technical solutions, the methods for obtaining the α-axis voltage control quantity and β-axis voltage control quantity based on the pre-calibrated composite cooperative control law, α-axis current component, β-axis current component, α-axis compensation voltage control quantity of the current current control cycle, and β-axis compensation voltage control quantity of the current current control cycle include: in, This is the voltage control quantity for the α-axis. This is the β-axis voltage control quantity. Let be the α-axis compensation voltage control quantity at time t. Let be the β-axis compensation voltage control quantity at time t. For repetitive control gain matrix, For the output feedback gain matrix, For the α-axis current component, This represents the β-axis current component.

[0044] The repetitive control compensation quantity based on the internal model principle and the fast-response output feedback quantity are fused and calculated in real time to form a composite cooperative control law, so as to generate αβ axis voltage control commands with high accuracy and fast response speed, thereby realizing high-precision zero steady-state error tracking of grid-connected current to reference commands and excellent dynamic adjustment performance.

[0045] In some technical solutions, the α-axis voltage control quantity and β-axis voltage control quantity are converted into a three-phase modulated voltage signal through Clarke inverse transform, and the drive signal of the LCL type three-phase grid-connected inverter is generated by the three-phase modulated voltage signal and the space vector pulse width modulation method. The α-axis voltage control quantity and β-axis voltage control quantity are converted into a three-phase modulated voltage signal using the following Clarke inverse transform: ; in, This is the real-time α-axis voltage control quantity. This is the real-time β-axis voltage control quantity. The voltage signal is modulated by phase a. This is a phase b modulated voltage signal. This is a c-phase modulated voltage signal; Using the SVPWM algorithm , , It is converted into six PWM drive signals to drive the IGBT switches.

[0046] In some embodiments, the SVPWM algorithm can be directly called in simulation software (such as MATLAB / Simulink) to implement... , , It is converted into six PWM drive signals.

[0047] The control commands, precisely calculated in the two-phase stationary coordinate system, are accurately reconstructed into three-phase modulated waveforms. The space vector pulse width modulation technology is then used to efficiently generate drive pulses, thereby ultimately controlling the operation of the power switching devices and enabling the inverter to output high-quality three-phase grid-connected current.

[0048] Figure 6 The graph compares the simulation errors of traditional repetitive control (RC) and complex coefficient repetitive control (CRC). The horizontal axis represents time, and the vertical axis represents tracking error. Comparing the tracking error of the present invention (CRC, solid black line) with that of the traditional method (RC, dashed orange line) within the same scenario and time period, it can be seen that the fluctuation of the control error curve of the present invention is consistently significantly smaller than that of the traditional method. The tracking error of the present invention converges quickly and remains stably at an extremely low level close to zero (approximately ±0.1 rpm), while the error value of the traditional method is larger (approximately ±0.5 rpm). This indicates that the tracking error of the present invention fluctuates only slightly within an extremely narrow band, exhibiting extremely high steady-state accuracy and stability. In contrast, the error fluctuation band of the traditional method is approximately twice that of the present invention, resulting in significantly inferior control accuracy.

[0049] In some embodiments, the implementation steps of the present invention include: Step 1: Provide the DC voltage source input value, and provide the target amplitude and frequency of the AC voltage across the load of the complex coefficient repetitive control module; Step 2: Measure the output current of the DC voltage source using a DC voltage source output current meter; Step 3: The complex coefficient repetitive control module acquires the voltage measurement value, inner loop current measurement value, and outer loop current measurement value from the load voltage measurement module. Through the action of negative feedback, it continuously adjusts the signal input of the modulation signal input ports of the four insulated gate field effect transistors, that is, by giving modulation signals S1, S2, S3, S4, S5, and S6 respectively, the on and off states of the six transistors are changed. Step 4: The series connection of resistors and inductors and the parallel connection of resistors and capacitors in the filter module will filter the output current of the inverter circuit. The inner loop current acquisition module will transmit the acquired information to the inner loop current receiving module, and the outer loop current acquisition module will transmit the acquired information to the outer loop current receiving module. Step 5: The complex coefficient repetitive control module processes the values ​​from the load voltage receiving module, inner loop current receiving module, and outer loop current receiving module through a complex coefficient filter and a complex coefficient repetitive controller. The structure of the complex coefficient repetitive control module is as follows: Figure 5 As shown; Step 6: The complex coefficient repetition control module transmits the final control signal to the modulation signal generation module; Step 7: The modulation signal generation module calculates the output of the modulation signal output ports of the six insulated gate field-effect transistors respectively; Step 8: The outputs of the modulation signals of the six insulated-gate field-effect transistors are respectively transmitted to the inputs of the six insulated-gate field-effect transistors, thereby completing the closed loop of control.

[0050] The simulation verification results based on the implementation steps of this invention are as follows: The simulation platform was built using MATLAB / Simulink, and the system parameters were set as follows: DC bus voltage Udc=700V, grid phase voltage RMS value 220V, frequency 50Hz, inverter side inductance L1=1.8mH, grid side inductance L2=1.0mH, filter capacitor Cf=10μF, parasitic resistance Rc=0.1Ω, and switching frequency 10kHz.

[0051] Controller parameters: filter cutoff frequency ωc = 300π rad / s, fundamental angular frequency ω0 = 100π rad / s, sampling period T = 100 μs. Control gains Ke and KP are obtained through LMI calculation.

[0052] like Figure 6 As shown, the current tracking error (in rpm) over time (s) is compared between the traditional repetitive control RC (orange dashed line) and the complex coefficient repetitive control CRC (black solid line) of this invention. The results show that: (1) Steady-state error: The peak-to-peak tracking error of the complex coefficient repetitive control strategy is only 49.12% of that of the traditional repetitive control strategy, which significantly improves the tracking accuracy; (2) THD index: After adopting the complex coefficient repetitive control strategy, the grid-connected current THD is reduced from 3.2% of the traditional repetitive control strategy to 1.5%, which meets the requirements of IEEE Std 1547 standard (THD<5%). (3) Dynamic response: When the reference current amplitude is changed at 0.1s, the adjustment time of the complex coefficient repetitive control strategy is about 2 cycles (0.04s), which is faster than the traditional repetitive control strategy of 3 cycles (0.06s). (4) Robustness: Under the condition of 10% grid voltage imbalance, the complex coefficient repetitive control strategy can still maintain good control performance, while the THD of RC rises to 5.8%.

[0053] Example 2 A highly reliable complex-coefficient repetitive control grid-connected inverter control method based on the system, suitable for power supply security scenarios, includes: Based on the topology and circuit parameters of the LCL three-phase grid-connected inverter, a state-space model characterizing the dynamic characteristics of the LCL three-phase grid-connected inverter is established. The grid-connected three-phase current on the grid side of the LCL three-phase grid-connected inverter is obtained based on the state-space model of the LCL three-phase grid-connected inverter. The grid-connected three-phase current is converted into current components in the αβ coordinate system through Clarke transformation to obtain α-axis current components and β-axis current components. The difference between the preset α-axis reference current and the α-axis current components is taken as the α-axis error current, and the difference between the preset β-axis reference current and the β-axis current components is taken as the β-axis error current. Based on the α-axis error current and β-axis error current of the current current control cycle, as well as the α-axis compensation voltage control quantity and β-axis compensation voltage control quantity obtained from the complex coefficient filter of the previous current control cycle, the difference is processed to obtain the intermediate α-axis compensation voltage control quantity and intermediate β-axis compensation voltage control quantity. The intermediate α-axis compensation voltage control quantity and intermediate β-axis compensation voltage control quantity are then filtered using a complex coefficient filter to obtain the α-axis compensation voltage control quantity and β-axis compensation voltage control quantity of the current current control cycle. The α-axis voltage control quantity and β-axis voltage control quantity are obtained based on the pre-calibrated composite cooperative control law, α-axis current component, β-axis current component, α-axis compensation voltage control quantity of the current current control cycle, and β-axis compensation voltage control quantity of the current current control cycle. The α-axis voltage control quantity and β-axis voltage control quantity are converted into a three-phase modulated voltage signal through Clarke inverse transformation, and the drive signal of the LCL type three-phase grid-connected inverter is generated by the three-phase modulated voltage signal and the space vector pulse width modulation method.

[0054] The present invention provides a computer-readable storage medium storing a computer program, which, when executed by a processor, performs the steps of the method described in Embodiment 2.

[0055] This invention can be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented in whole or in part as a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of this invention are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that integrates one or more available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., a solid-state drive (SSD)).

[0056] It will be readily understood by those skilled in the art that the above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, combinations, substitutions, improvements, etc., made under the spirit and principles of the present invention are included within the protection scope of the present invention.

[0057] The contents not described in detail in this specification are existing technologies known to those skilled in the art.

Claims

1. A high-reliability complex-coefficient repetitive control grid-connected inverter control system suitable for power supply security scenarios, characterized in that, It includes: The state-space model building module is used to build a state-space model characterizing the dynamic characteristics of the LCL three-phase grid-connected inverter based on the topology and circuit parameters of the LCL three-phase grid-connected inverter. The grid-connected three-phase current on the grid side of the LCL three-phase grid-connected inverter is obtained based on the state-space model of the LCL three-phase grid-connected inverter. The current error signal generation module is used to convert the grid-connected three-phase current into current components in the αβ coordinate system through Clarke transformation, to obtain α-axis current components and β-axis current components. The difference between the preset α-axis reference current and the α-axis current components is used as the α-axis error current, and the difference between the preset β-axis reference current and the β-axis current components is used as the β-axis error current. The complex coefficient repetitive control module is used to perform subtraction processing on the α-axis error current and β-axis error current of the current current control cycle and the α-axis compensation voltage control quantity and β-axis compensation voltage control quantity obtained by the complex coefficient filter of the previous current control cycle to obtain the intermediate state α-axis compensation voltage control quantity and intermediate state β-axis compensation voltage control quantity. The complex coefficient filter is then used to filter the intermediate state α-axis compensation voltage control quantity and intermediate β-axis compensation voltage control quantity to obtain the α-axis compensation voltage control quantity and β-axis compensation voltage control quantity of the current current control cycle. The control voltage acquisition module is used to obtain the α-axis voltage control quantity and the β-axis voltage control quantity based on the pre-calibrated composite cooperative control law, α-axis current component, β-axis current component, α-axis compensation voltage control quantity of the current current control cycle, and β-axis compensation voltage control quantity of the current current control cycle. The modulation signal conversion module is used to convert the α-axis voltage control quantity and β-axis voltage control quantity into a three-phase modulated voltage signal through Clarke inverse transformation, and to generate the drive signal of the LCL type three-phase grid-connected inverter through the three-phase modulated voltage signal and the space vector pulse width modulation method.

2. The high-reliability complex-coefficient repetitive control grid-connected inverter control system suitable for power supply scenarios according to claim 1, characterized in that: Based on the topology and circuit parameters of an LCL-type three-phase grid-connected inverter, a state-space model characterizing the dynamic characteristics of the LCL-type three-phase grid-connected inverter is established in the αβ stationary coordinate system. Methods for obtaining the grid-connected three-phase current on the grid side of the LCL-type three-phase grid-connected inverter from the state-space model include: ； in, Let m be the state vector, T be the transpose operator, and m = a, b, c. This refers to the phase a current on the inverter side of an LCL-type three-phase grid-connected inverter. This refers to the b-phase current on the inverter side of an LCL-type three-phase grid-connected inverter. This refers to the c-phase current on the inverter side of an LCL-type three-phase grid-connected inverter. This refers to the phase a capacitor voltage of an LCL-type three-phase grid-connected inverter. This refers to the voltage of the b-phase capacitor in an LCL-type three-phase grid-connected inverter. This refers to the voltage of the c-phase capacitor in an LCL-type three-phase grid-connected inverter. This refers to the phase a current on the grid side of the LCL-type three-phase grid-connected inverter. This refers to the phase b current on the grid side of the LCL-type three-phase grid-connected inverter. This refers to the c-phase current on the grid side of the LCL-type three-phase grid-connected inverter. For the input vector, This refers to the output voltage of phase a of the LCL-type three-phase grid-connected inverter. This refers to the output voltage of phase b of the LCL-type three-phase grid-connected inverter. This refers to the output voltage of the C-phase bridge arm of the LCL-type three-phase grid-connected inverter. Let A be the disturbance vector containing the grid voltage term, B be the system matrix containing inductance, capacitance, and parasitic resistance parameters, C be the input matrix determined by the inverter-side inductance, and D be the grid-side current output matrix of the LCL-type three-phase grid-connected inverter. This refers to the grid-connected three-phase current on the grid side of the LCL-type three-phase grid-connected inverter.

3. The high-reliability complex-coefficient repetitive control grid-connected inverter control system suitable for power supply scenarios according to claim 2, characterized in that: The method for converting the grid-connected three-phase current into current components in the αβ coordinate system using Clarke transformation to obtain the α-axis current component and the β-axis current component includes: ， ； in, Let α be the α-axis current component in the αβ coordinate system. The β-axis current component in the αβ coordinate system. This refers to the phase a current on the grid side of the LCL-type three-phase grid-connected inverter. This refers to the phase b current on the grid side of the LCL-type three-phase grid-connected inverter. This refers to the c-phase current on the grid side of the LCL-type three-phase grid-connected inverter.

4. A high-reliability complex-coefficient repetitive control grid-connected inverter control system suitable for power supply scenarios, as described in claim 3, is characterized in that: The method for obtaining the intermediate-state α-axis compensation voltage control quantity and β-axis compensation voltage control quantity based on the α-axis error current and β-axis error current of the current current control cycle, and the α-axis compensation voltage control quantity and β-axis compensation voltage control quantity obtained by the complex coefficient filter of the previous current control cycle, includes the following steps: ； ； ； in, For the complex coefficient repetitive controller at time t, the intermediate calculated variable represents the difference signal generated after comparing the current period error with historical memory information. For the α-axis error current, This is the β-axis error current. for The intermediate state α-axis compensation voltage control quantity at time t. for The intermediate state β-axis compensation voltage control quantity at time t. Let be the intermediate state α-axis compensation voltage control quantity at time t. Let be the intermediate state β-axis compensation voltage control quantity at time t. Let be the α-axis compensation voltage control quantity at time t. Let be the β-axis compensation voltage control quantity at time t. Let be the transfer function of the complex coefficient filter. For the current control cycle, This is the output voltage control signal for the complex coefficient repetitive controller.

5. A high-reliability complex-coefficient repetitive control grid-connected inverter control system suitable for power supply scenarios, as described in claim 4, is characterized in that: The transfer function of the complex coefficient filter is: ； The α-axis compensation voltage control quantity at time t As the real part of the complex signal, the β-axis compensation voltage at time t is controlled. As the imaginary part of a complex signal, then ,right Performing a Laplace transform on both sides of the equation, we get... , Will Substitution get: ； United and get: ； right Performing the inverse Laplace transform yields the differential equation for the complex coefficient filter, which is used to solve for the α-axis compensation voltage control quantity. β-axis compensation voltage control quantity : ； Where ωc is the filter cutoff frequency. Here, ω is the imaginary part parameter, and ω0 is the fundamental angular frequency of the power grid. For complex variables, The imaginary unit, For Hilbert transform, for Laplace transform, for Laplace transform, for Laplace transform, for Laplace transform, Let be the intermediate state α-axis compensation voltage control quantity at time t. Let be the intermediate state β-axis compensation voltage control quantity at time t. Let be the α-axis compensation voltage control quantity at time t. Let be the β-axis compensation voltage control quantity at time t. Let be the first derivative of the intermediate state α-axis compensation voltage control quantity at time t. It is the first derivative of the intermediate state β-axis compensation voltage control quantity at time t.

6. A high-reliability complex-coefficient repetitive control grid-connected inverter control system suitable for power supply scenarios, as described in claim 4, is characterized in that: The method for obtaining the pre-calibrated composite cooperative control law includes: constructing a complex coefficient repetitive control system from the state-space model of an LCL-type three-phase grid-connected inverter, a complex coefficient repetitive controller, and the composite cooperative control law; using Lyapunov stability theory as constraints; and solving the linear matrix inequality (LMI) to obtain the repetitive control gain matrix Ke and the output feedback gain matrix KP that satisfy Lyapunov stability theory for the complex coefficient repetitive control system; and then obtaining the pre-calibrated composite cooperative control law. , ; in, For repetitive control gain matrix, For the output feedback gain matrix, This is the output voltage control signal for the complex coefficient repetitive controller. This represents the current components of the grid-connected three-phase current on the grid side of the LCL-type three-phase grid-connected inverter in the αβ coordinate system. Let α be the α-axis current component in the αβ coordinate system. The β-axis current component in the αβ coordinate system. This is the final voltage control value.

7. A high-reliability complex-coefficient repetitive control grid-connected inverter control system suitable for power supply scenarios, as described in claim 6, is characterized in that: The methods for obtaining the α-axis voltage control quantity and β-axis voltage control quantity based on the pre-calibrated composite cooperative control law, α-axis current component, β-axis current component, α-axis compensation voltage control quantity of the current current control cycle, and β-axis compensation voltage control quantity of the current current control cycle include: in, This is the voltage control quantity for the α-axis. This is the β-axis voltage control quantity. Let be the α-axis compensation voltage control quantity at time t. Let be the β-axis compensation voltage control quantity at time t. For repetitive control gain matrix, For the output feedback gain matrix, For the α-axis current component, This represents the β-axis current component.

8. A high-reliability complex-coefficient repetitive control grid-connected inverter control system suitable for power supply scenarios, as described in claim 7, is characterized in that: The method of converting α-axis and β-axis voltage control quantities into three-phase modulated voltage signals using Clarke inverse transform, and then generating drive signals for LCL-type three-phase grid-connected inverters using the three-phase modulated voltage signals and space vector pulse width modulation includes: The α-axis voltage control quantity and β-axis voltage control quantity are converted into a three-phase modulated voltage signal using the following Clarke inverse transform: ； in, This is the real-time α-axis voltage control quantity. This is the real-time β-axis voltage control quantity. The voltage signal is modulated by phase a. This is a phase b modulated voltage signal. This is a c-phase modulated voltage signal; Using the SVPWM algorithm , , It is converted into six PWM drive signals to drive the IGBT switches.

9. A high-reliability complex-coefficient repetitive control grid-connected inverter control method based on the system of claim 1, suitable for power supply guarantee scenarios, characterized in that, include: Based on the topology and circuit parameters of the LCL three-phase grid-connected inverter, a state-space model characterizing the dynamic characteristics of the LCL three-phase grid-connected inverter is established. The grid-connected three-phase current on the grid side of the LCL three-phase grid-connected inverter is obtained based on the state-space model of the LCL three-phase grid-connected inverter. The grid-connected three-phase current is converted into current components in the αβ coordinate system through Clarke transformation to obtain α-axis current components and β-axis current components. The difference between the preset α-axis reference current and the α-axis current components is taken as the α-axis error current, and the difference between the preset β-axis reference current and the β-axis current components is taken as the β-axis error current. Based on the α-axis error current and β-axis error current of the current current control cycle, as well as the α-axis compensation voltage control quantity and β-axis compensation voltage control quantity obtained from the complex coefficient filter of the previous current control cycle, the difference is processed to obtain the intermediate α-axis compensation voltage control quantity and intermediate β-axis compensation voltage control quantity. The intermediate α-axis compensation voltage control quantity and intermediate β-axis compensation voltage control quantity are then filtered using a complex coefficient filter to obtain the α-axis compensation voltage control quantity and β-axis compensation voltage control quantity of the current current control cycle. The α-axis voltage control quantity and β-axis voltage control quantity are obtained based on the pre-calibrated composite cooperative control law, α-axis current component, β-axis current component, α-axis compensation voltage control quantity of the current current control cycle, and β-axis compensation voltage control quantity of the current current control cycle. The α-axis voltage control quantity and β-axis voltage control quantity are converted into a three-phase modulated voltage signal through Clarke inverse transformation, and the drive signal of the LCL type three-phase grid-connected inverter is generated by the three-phase modulated voltage signal and the space vector pulse width modulation method.

10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method of claim 9.

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