A method and device for adaptive adjustment of control parameters of a network-forming converter

Abstract

The application relates to the technical field of power systems, and discloses a grid-forming converter control parameter adaptive adjustment method and device, which monitors output current and output voltage of a grid-forming converter in real time, calculates voltage and current disturbance according to a small signal model of the grid-forming converter, dynamically updates parameters of a PID controller or a PI controller according to a preset adaptive gain adjustment model, adjusts a control signal for controlling the output voltage and the output current of the grid-forming converter in real time, and stabilizes the output voltage and the output current of the grid-forming converter. Dynamically adjusting the parameters of the PID controller or the PI controller and adjusting the control signal in real time based on the adjusted parameters can ensure the stability of the output current and the output voltage of the grid-forming converter, guarantee the stability of the grid-forming converter in a power grid, and solve the technical problem that the prior art lacks an effective technical means of adaptively adjusting the control parameters of the grid-forming converter to maintain stable operation of the power grid system.

Description

Technical Field

[0001] This invention relates to the field of power system technology, and in particular to a method and apparatus for adaptive adjustment of control parameters of grid converters. Background Technology

[0002] Grid-Forming Inverters (GFIs), as devices simulating the inertia of synchronous machines, maintain grid stability by controlling voltage and frequency. To understand their dynamic behavior under disturbances, small-signal models are typically used for linearization analysis. The purpose of small-signal models is to study how the system responds to grid disturbances or load changes. Generally, in small-signal analysis, it is assumed that the system experiences small disturbances near a stable operating point. By linearizing the control system, a set of transfer functions is obtained to describe the system's dynamic characteristics. Currently, how to adaptively adjust the control parameters of grid-forming inverters to ensure rapid and oscillating response within the grid system, thereby achieving stable grid operation, remains a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0003] This invention provides a method and apparatus for adaptive adjustment of control parameters of grid-connected converters, which solves the technical problem that the prior art lacks an effective technical means to adaptively adjust the control parameters of grid-connected converters to maintain the stable operation of the power grid system.

[0004] In view of this, the first aspect of the present invention provides a method for adaptive adjustment of control parameters of a grid converter, comprising:

[0005] Construct a small-signal model of a grid-type converter;

[0006] Real-time acquisition of the output current and output voltage of the grid-type converter;

[0007] Based on the output current and output voltage of the grid converter, the current disturbance and voltage disturbance of the grid converter are calculated using a small-signal model.

[0008] Based on the current and voltage disturbances of the grid converter, the parameters of the PID controller or PI controller are dynamically updated according to the preset adaptive gain adjustment model.

[0009] Based on the updated parameters of the PID controller or PI controller, the control signals used to control the output voltage and output current of the grid converter are adjusted in real time to stabilize the output voltage and output current of the grid converter.

[0010] Optionally, the small-signal model of the grid-connected converter includes a model of the current control loop, a model of the voltage control loop, and a state-space model of the grid connection point.

[0011] Alternatively, the model for the current control loop is:

[0012]

[0013] in, Let be the transfer function of the current control loop. This is the actual output current. For reference current, For the gain of the current control loop, Let be the time constant of the current control loop, and s be the complex variable in the Laplace transform.

[0014] Alternatively, the voltage control loop model is as follows:

[0015]

[0016] in, Let be the transfer function of the voltage control loop. This is the actual output current. For reference voltage, This is the gain of the voltage control loop. Let be the time constant of the voltage control loop, and s be the complex variable in the Laplace transform.

[0017] Optionally, the state-space model of the power grid connection point is:

[0018]

[0019] in, The transfer function of the power grid connection point. This is the grid voltage. Let be the grid current, and s be the complex variable in the Laplace transform. The equivalent impedance of the power grid connection point. This is the characteristic matrix of the power grid connection points.

[0020] Optionally, the preset adaptive gain adjustment model is:

[0021]

[0022] in, Let be the gain of the current control loop at time t. Let be the gain of the current control loop at time t-1. Adjust the step size for current gain. Let be the gain of the voltage control loop at time t. Let be the gain of the voltage control loop at time t-1. Adjust the step size for voltage gain.

[0023] Optionally, the formula for calculating the current gain adjustment step size is:

[0024]

[0025] in, For current adaptive gain, Let t be the current disturbance at time t.

[0026] Optionally, the formula for calculating the voltage gain adjustment step size is:

[0027]

[0028] in, For voltage adaptive gain, Let t be the voltage disturbance at time t.

[0029] A second aspect of the present invention provides an adaptive adjustment device for control parameters of a grid converter, comprising:

[0030] The small-signal model construction module is used to construct the small-signal model of a grid-type converter.

[0031] The acquisition module is used to acquire the output current and output voltage of the grid-type converter in real time;

[0032] The disturbance calculation module is used to calculate the current disturbance and voltage disturbance of the grid-type converter based on the output current and output voltage of the grid-type converter and the small-signal model.

[0033] The parameter adjustment module is used to dynamically update the parameters of the PID controller or PI controller based on the current disturbance and voltage disturbance of the grid-type converter and according to the preset adaptive gain adjustment model.

[0034] The control module is used to adjust the control signals for controlling the output voltage and output current of the grid converter in real time based on the updated parameters of the PID controller or PI controller, so as to stabilize the output voltage and output current of the grid converter.

[0035] Optionally, the preset adaptive gain adjustment model is:

[0036]

[0037] in, Let be the gain of the current control loop at time t. Let be the gain of the current control loop at time t-1. Adjust the step size for current gain. Let be the gain of the voltage control loop at time t. Let be the gain of the voltage control loop at time t-1. Adjust the step size for voltage gain.

[0038] As can be seen from the above technical solutions, the adaptive adjustment method for grid converter control parameters provided by the present invention has the following advantages:

[0039] The adaptive adjustment method for control parameters of a grid-connected converter provided by this invention monitors the output current and output voltage of the grid-connected converter in real time. It calculates voltage and current disturbances based on the small-signal model of the grid-connected converter, and then dynamically updates the parameters of the PID controller or PI controller according to a preset adaptive gain adjustment model. Based on the updated parameters, it adjusts the control signals used to control the output voltage and output current of the grid-connected converter in real time, thereby stabilizing the output voltage and output current of the grid-connected converter. Dynamically adjusting the parameters of the PID controller or PI controller and adjusting the control signals in real time based on the adjusted parameters ensures the stability of the output current and output voltage of the grid-connected converter, effectively guaranteeing the stability of the grid-connected converter in the power grid. This solves the technical problem of the lack of effective means in the prior art for adaptively adjusting the control parameters of grid-connected converters to maintain the stable operation of the power grid system. Attached Figure Description

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

[0041] Figure 1 This is a flowchart illustrating an adaptive adjustment method for grid converter control parameters provided in an embodiment of the present invention.

[0042] Figure 2 This is a schematic diagram of the structure of an adaptive adjustment device for control parameters of a grid converter provided in an embodiment of the present invention. Detailed Implementation

[0043] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0044] For easier understanding, please refer to Figure 1 This invention provides an embodiment of an adaptive adjustment method for control parameters of a grid converter, comprising:

[0045] Step 101: Construct the small-signal model of the grid-type converter.

[0046] It should be noted that when a grid-connected converter is connected to the power grid, its small-signal model is used to analyze its dynamic response and stability. The small-signal model mainly includes models of the current control loop, voltage control loop, and state-space model of the grid connection point. These models can be approximated using linearization methods to analyze the system's stability. In small-signal analysis, it can be assumed that the system operates near a stable operating point, and linearization analysis can be performed on deviations from this operating point.

[0047] The primary function of the current control loop is to achieve power control by adjusting the converter's output current. In small-signal analysis, the current control loop can be modeled as a transfer function. Let the reference current be... The actual output current is The gain of the current control loop is The state-space equations of the current control loop are:

[0048]

[0049]

[0050] in, for The first derivative with respect to time t, This is the state matrix of the current control loop, used to describe the dynamic characteristics of the current control loop's state variables (such as inductor current) as a function of time. This is the input matrix of the current control loop, used to represent the contribution of the input signal (such as the current reference signal) to the changes in the state variables. This is the output matrix of the current control loop, used to map state variables to output signals (such as actual current output). This is the direct transfer matrix of the current control loop, used to represent the path (usually 0 or a minimum value) from the input signal directly to the output. These are the state variables of the current control loop. For input signal, This is the current output signal.

[0051] By linearizing the small signal, the transfer function of the current control loop can be obtained as follows:

[0052]

[0053] in, Let be the transfer function of the current control loop. This is the actual output current. For reference current, For the gain of the current control loop, Let be the time constant of the current control loop, and s be the complex variable in the Laplace transform.

[0054] The task of the voltage control loop is to maintain a stable output voltage of the converter. The dynamic behavior of the voltage control loop can be determined by a reference voltage. With actual output voltage The error between them is analyzed. Its mathematical model can also be established through small-signal linearization. The state-space model of the voltage control loop is:

[0055]

[0056]

[0057] in, for The first derivative with respect to time t, This is the state matrix of the voltage control loop, used to describe the dynamic characteristics of the voltage control loop's state variables (such as capacitor voltage). This is the input matrix of the voltage control loop, used to represent the effect of input signals (such as voltage reference signals or current control loop outputs) on state variables. This is the output matrix of the voltage control loop, used to map state variables to output voltage signals. This is the direct transfer matrix for the voltage control loop, used to represent the path from the input signal directly to the output. These are the state variables of the voltage control loop. For input signals (such as reference voltage). This is the voltage output signal.

[0058] By linearizing the small signal, the transfer function of the current control loop can be obtained as follows:

[0059]

[0060] in, Let be the transfer function of the voltage control loop. This is the actual output current. For reference voltage, This is the gain of the voltage control loop. Let be the time constant of the voltage control loop, and s be the complex variable in the Laplace transform.

[0061] When a grid-connected converter is connected to the power grid, the grid's state variables are closely related to the converter's output current and voltage. At the connection point, the grid's voltage and current will interact with the converter's output. Let the grid voltage be... The grid current is The connection between the converter and the power grid can be represented by the following state-space model:

[0062]

[0063]

[0064] in, for The first derivative with respect to time t, This is the state matrix of the grid connection points, used to describe the dynamic characteristics of grid-side state variables (such as grid voltage and current). This is the input matrix for the grid connection point, used to represent the impact of the converter output current / voltage on the grid state variables. The output matrix for the grid connection point is used to map grid state variables to output signals (such as grid terminal voltage or current). This is the direct transfer matrix for the power grid connection point, used to reflect the path of the input signal directly transmitted to the output. For the state variables of the power grid connection points, For input signals (such as the current or voltage of the converter). This is the voltage output signal (such as mains voltage or current). The transfer function of the mains connection point is:

[0065]

[0066] in, The transfer function of the power grid connection point. This is the grid voltage. Let be the grid current, and s be the complex variable in the Laplace transform. The equivalent impedance of the power grid connection point. This is the characteristic matrix of the power grid connection points.

[0067] The overall system of a grid-connected converter consists of the interaction of a current control loop, a voltage control loop, and grid connection points. Combining the state-space models of the current control loop, voltage control loop, and grid connection points yields the state-space model of the entire system. Let the system's state vector be... The input vector is The output vector is The state-space model of the entire system is as follows:

[0068]

[0069]

[0070] Among them, matrices A, B, C, and D are composed of the respective matrices of the current control loop, voltage control loop, and grid connection point.

[0071] Step 102: Obtain the output current and output voltage of the grid-type converter in real time.

[0072] It should be noted that the output current and output voltage of the grid-type converter are monitored in real time by sensors.

[0073] Step 103: Based on the output current and output voltage of the grid converter, calculate the current disturbance and voltage disturbance of the grid converter using a small-signal model.

[0074] It should be noted that, for stability analysis, the overall system of the grid-type converter needs to be linearized. For the state-space model of a nonlinear system, the Taylor expansion method can be used to linearize it near the equilibrium point. First, assume the equilibrium state vector of the system is... , representing the steady-state value of the state variable when the system is running stably, and the small-signal disturbance of the system is . The disturbance of the input signal is , Let be the system equilibrium point input vector, representing the steady-state value of the input signal, and let be the disturbance of the output signal. , Let be the output vector at the system equilibrium point, representing the steady-state value of the output signal. Expanding this, we obtain the small-signal model of the system:

[0075]

[0076]

[0077] in, For small-signal perturbations of state variables, for The first derivative, It is a state matrix used to describe the dynamic coupling relationship between state variables (composed of the Jacobian matrix of the current loop, voltage loop, and power grid connection model). This is the input matrix, used to describe the effect of the input signal on the state variables (such as the driving effect of the reference current / voltage on the state change). The output matrix describes the mapping relationship between state variables and output signals (such as how grid voltage / current is derived from state variables). The direct transfer matrix is ​​used to describe the direct transfer relationship from the input signal to the output signal (it can usually be ignored in small-signal models, i.e., D≈0).

[0078] The overall transfer function of a system is the combination of the transfer functions of all its components, and the stability of the system can be analyzed through the transfer function. Eigenvalue analysis is used to examine the system's poles. If all poles are located in the left half of the complex plane, the system is stable. If any pole is located in the right half of the complex plane, the system is unstable.

[0079] Stability analysis is performed by analyzing the location of the system's poles. The pole locations can be obtained by solving for the eigenvalues ​​of the system matrix. Let the system's state-space matrix be A, and its characteristic equation be:

[0080]

[0081] in, For determinant calculation, I is the identity matrix, and s is the eigenvalues ​​of the state matrix A (i.e., the poles of the system), which can be calculated using linear algebra.

[0082] Solve the characteristic equation to obtain the poles of the system. If the real parts of all poles are negative, the system is stable. If the real parts of any pole are positive, the system is unstable.

[0083] Step 104: Based on the current disturbance and voltage disturbance of the grid-type converter, dynamically update the parameters of the PID controller or PI controller according to the preset adaptive gain adjustment model.

[0084] It should be noted that in the control design of grid-type converters, PID controllers / PI controllers are used to adjust the stability of current, voltage, and power.

[0085] The transfer function of the PID controller is:

[0086]

[0087] in, For proportional parameters, For integration parameters, Let be the differential parameter, and s be the complex variable in the Laplace transform.

[0088] The transfer function of the PI controller is:

[0089]

[0090] in, For proportional parameters, Let be the integration parameter, and s be the complex variable in the Laplace transform.

[0091] By adjusting , and The value of can change the system's response speed and steady-state error, thereby keeping the system stable at the grid connection point.

[0092] To maintain the real-time stability of a system, adaptive algorithms are used to adjust the parameters of a PID or PI controller. This typically involves real-time monitoring of the system's state (such as frequency, load, voltage, etc.) and dynamically adjusting the controller's gain based on the response of the small-signal model.

[0093] For the current control loop, the current control error (such as current disturbance) is calculated in real time. and voltage disturbance This allows us to determine the gain of the current control loop.

[0094] The goal of adaptive algorithms is to dynamically adjust the gain. This is to ensure the stability of the current control loop. The goal of this gain adjustment is to control the system's pole locations within the left half-plane. This can be achieved using the following adaptive algorithm. :

[0095]

[0096] in, To dynamically adjust the gain The first derivative with respect to time t, It is a current adaptive gain, which controls the adjustment rate of the current gain. Let be the current disturbance at time t. Based on the system response, the gain... The control performance will dynamically adjust over time.

[0097] Similarly, the gain of the voltage control loop can also be achieved through adaptive adjustment. The gain adjustment of the adaptive algorithm can be expressed as:

[0098]

[0099] in, For gain The first derivative with respect to time t, For voltage adaptive gain, it controls the adjustment rate of the voltage gain. Let be the voltage disturbance at time t. Based on the system response, the gain... The control performance will dynamically adjust over time.

[0100] Design an adaptive function for:

[0101]

[0102] Where P is a positive definite matrix, and x is the system's state variable. To ensure system stability, it is necessary to make... The derivative of the function is negative:

[0103]

[0104] Here, Q is a positive definite symmetric matrix used to construct the derivative conditions of the adaptive function F(x). It can be directly set as a diagonal matrix to adjust the convergence speed.

[0105] If the gain is adjusted according to the current system state and This makes the system's adaptive function Maintaining a decreasing gain ensures system stability. Specifically, the gain adjustment equation is:

[0106]

[0107] The adaptive gain can be dynamically updated based on the system's feedback signals (current error, voltage error, etc.):

[0108]

[0109] in, Let be the gain of the current control loop at time t. Let be the gain of the current control loop at time t-1. Adjust the step size for current gain. Let be the gain of the voltage control loop at time t.

[0110] The formula for calculating the current gain adjustment step size is:

[0111]

[0112] in, For current adaptive gain, Let t be the current disturbance at time t.

[0113] The formula for calculating the voltage gain adjustment step size is:

[0114]

[0115] in, For voltage adaptive gain, Let t be the voltage disturbance at time t.

[0116] Step 105: Based on the updated parameters of the PID controller or PI controller, adjust the control signals used to control the output voltage and output current of the grid converter in real time to stabilize the output voltage and output current of the grid converter.

[0117] It should be noted that, based on the adjusted gain, the control signal is adjusted in real time to ensure the stability of the converter's output current and voltage.

[0118] To illustrate more specifically the implementation of the adaptive adjustment method for grid converter control parameters provided in this embodiment of the invention, a specific application example is provided below:

[0119] Assume the initial gain of the current control loop is The initial gain of the voltage control loop is The current adaptive gain is Voltage adaptive gain is The current deviation is Voltage deviation Adjust the gain using the following formula:

[0120]

[0121] The new value after gain adjustment is:

[0122]

[0123] Based on this algorithm, the gain of the PID controller / PI controller is adjusted in real time, enabling the system to adapt to dynamic changes in the power grid and remain stable.

[0124] The adaptive adjustment method for control parameters of a grid-connected converter provided by this invention monitors the output current and output voltage of the grid-connected converter in real time. It calculates voltage and current disturbances based on the small-signal model of the grid-connected converter, and then dynamically updates the parameters of the PID controller or PI controller according to a preset adaptive gain adjustment model. Based on the updated parameters, it adjusts the control signals used to control the output voltage and output current of the grid-connected converter in real time, thereby stabilizing the output voltage and output current of the grid-connected converter. Dynamically adjusting the parameters of the PID controller or PI controller and adjusting the control signals in real time based on the adjusted parameters ensures the stability of the output current and output voltage of the grid-connected converter, effectively guaranteeing the stability of the grid-connected converter in the power grid. This solves the technical problem of the lack of effective means in the prior art for adaptively adjusting the control parameters of grid-connected converters to maintain the stable operation of the power grid system.

[0125] For easier understanding, please refer to Figure 2 An embodiment of an adaptive adjustment device for control parameters of a grid converter provided in this invention includes:

[0126] The small-signal model construction module is used to construct the small-signal model of a grid-type converter.

[0127] The acquisition module is used to acquire the output current and output voltage of the grid-type converter in real time;

[0128] The disturbance calculation module is used to calculate the current disturbance and voltage disturbance of the grid-type converter based on the output current and output voltage of the grid-type converter and the small-signal model.

[0129] The parameter adjustment module is used to dynamically update the parameters of the PID controller or PI controller based on the current disturbance and voltage disturbance of the grid-type converter and according to the preset adaptive gain adjustment model.

[0130] The control module is used to adjust the control signals for controlling the output voltage and output current of the grid converter in real time based on the updated parameters of the PID controller or PI controller, so as to stabilize the output voltage and output current of the grid converter.

[0131] In one embodiment, the small-signal model of a grid-connected converter includes a model of the current control loop, a model of the voltage control loop, and a state-space model of the grid connection point.

[0132] In one embodiment, the current control loop model is as follows:

[0133]

[0134] in, Let be the transfer function of the current control loop. This is the actual output current. For reference current, For the gain of the current control loop, Let be the time constant of the current control loop, and s be the complex variable in the Laplace transform.

[0135] In one embodiment, the voltage control loop model is as follows:

[0136]

[0137] in, Let be the transfer function of the voltage control loop. This is the actual output current. For reference voltage, This is the gain of the voltage control loop. Let be the time constant of the voltage control loop, and s be the complex variable in the Laplace transform.

[0138] In one embodiment, the state-space model of the power grid connection point is as follows:

[0139]

[0140] in, The transfer function of the power grid connection point. This is the grid voltage. Let be the grid current, and s be the complex variable in the Laplace transform. The equivalent impedance of the power grid connection point. This is the characteristic matrix of the power grid connection points.

[0141] In one embodiment, the preset adaptive gain adjustment model is:

[0142]

[0143] in, Let be the gain of the current control loop at time t. Let be the gain of the current control loop at time t-1. Adjust the step size for current gain. Let be the gain of the voltage control loop at time t. Let be the gain of the voltage control loop at time t-1. Adjust the step size for voltage gain.

[0144] In one embodiment, the formula for calculating the current gain adjustment step size is:

[0145]

[0146] in, For current adaptive gain, Let t be the current disturbance at time t.

[0147] In one embodiment, the formula for calculating the voltage gain adjustment step size is:

[0148]

[0149] in, For voltage adaptive gain, Let t be the voltage disturbance at time t.

[0150] The adaptive adjustment device for grid converter control parameters provided in this invention is used to execute the adaptive adjustment method for grid converter control parameters provided in this invention. Its technical effects have been described in the embodiments of the adaptive adjustment method for grid converter control parameters provided in this invention, and will not be repeated here.

[0151] The terms “first,” “second,” “third,” etc., used in this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of the invention described herein can be implemented, for example, in orders other than those illustrated or described herein. Furthermore, 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 may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0152] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for adaptive adjustment of control parameters of a grid-connected converter, characterized in that, include: Construct a small-signal model of a grid-type converter; Real-time acquisition of the output current and output voltage of the grid-type converter; Based on the output current and output voltage of the grid converter, the current disturbance and voltage disturbance of the grid converter are calculated using a small-signal model. Based on the current and voltage disturbances of the grid converter, the parameters of the PID controller or PI controller are dynamically updated according to the preset adaptive gain adjustment model. Based on the updated parameters of the PID controller or PI controller, the control signals used to control the output voltage and output current of the grid converter are adjusted in real time to stabilize the output voltage and output current of the grid converter. The small-signal model of a grid-connected converter includes the model of the current control loop, the model of the voltage control loop, and the state-space model of the grid connection point; The model of the current control loop is as follows: ； in, Let be the transfer function of the current control loop. This is the actual output current. For reference current, For the gain of the current control loop, is the time constant of the current control loop, and s is a complex variable in the Laplace transform; The model for the voltage control loop is as follows: ； in, Let be the transfer function of the voltage control loop. This is the actual output current. For reference voltage, This is the gain of the voltage control loop. is the time constant of the voltage control loop, and s is a complex variable in the Laplace transform; The state-space model of the power grid connection point is as follows: ； in, The transfer function of the power grid connection point. This is the grid voltage. Let be the grid current, and s be the complex variable in the Laplace transform. The equivalent impedance of the power grid connection point. This is the characteristic matrix of the power grid connection points.

2. The adaptive adjustment method for control parameters of a grid converter according to claim 1, characterized in that, The preset adaptive gain adjustment model is: ； in, Let be the gain of the current control loop at time t. Let be the gain of the current control loop at time t-1. Adjust the step size for current gain. Let be the gain of the voltage control loop at time t. Let be the gain of the voltage control loop at time t-1. Adjust the step size for voltage gain.

3. The adaptive adjustment method for control parameters of a grid converter according to claim 2, characterized in that, The formula for calculating the current gain adjustment step size is: ； in, For current adaptive gain, Let t be the current disturbance at time t.

4. The adaptive adjustment method for control parameters of a grid converter according to claim 2, characterized in that, The formula for calculating the voltage gain adjustment step size is: ； in, For voltage adaptive gain, Let t be the voltage disturbance at time t.

5. An adaptive adjustment device for control parameters of a grid-connected converter, characterized in that, include: The small-signal model construction module is used to construct the small-signal model of a grid-type converter. The acquisition module is used to acquire the output current and output voltage of the grid-type converter in real time; The disturbance calculation module is used to calculate the current disturbance and voltage disturbance of the grid-type converter based on the output current and output voltage of the grid-type converter and the small-signal model. The parameter adjustment module is used to dynamically update the parameters of the PID controller or PI controller based on the current disturbance and voltage disturbance of the grid-type converter and according to the preset adaptive gain adjustment model. The control module is used to adjust the control signals for controlling the output voltage and output current of the grid converter in real time based on the updated parameters of the PID controller or PI controller, so as to stabilize the output voltage and output current of the grid converter. The small-signal model of a grid-connected converter includes the model of the current control loop, the model of the voltage control loop, and the state-space model of the grid connection point; The model of the current control loop is as follows: ； in, Let be the transfer function of the current control loop. This is the actual output current. For reference current, For the gain of the current control loop, is the time constant of the current control loop, and s is a complex variable in the Laplace transform; The model for the voltage control loop is as follows: ； in, Let be the transfer function of the voltage control loop. This is the actual output current. For reference voltage, This is the gain of the voltage control loop. is the time constant of the voltage control loop, and s is a complex variable in the Laplace transform; The state-space model of the power grid connection point is as follows: ； in, The transfer function of the power grid connection point. This is the grid voltage. Let be the grid current, and s be the complex variable in the Laplace transform. The equivalent impedance of the power grid connection point. This is the characteristic matrix of the power grid connection points.

6. The adaptive adjustment device for control parameters of a grid converter according to claim 5, characterized in that, The preset adaptive gain adjustment model is: ； in, Let be the gain of the current control loop at time t. Let be the gain of the current control loop at time t-1. Adjust the step size for current gain. Let be the gain of the voltage control loop at time t. Let be the gain of the voltage control loop at time t-1. Adjust the step size for voltage gain.

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