Self-adaptive adjustment method and device for control parameters of network construction converter

Abstract

The invention relates to the technical field of power systems, and discloses a self-adaptive adjustment method and device for control parameters of a network-building converter, and the method comprises the steps: monitoring the output current and the output voltage of the network-building converter in real time, calculating the voltage and current disturbance according to a small-signal model of the network-building converter, and then carrying out the self-adaptive adjustment of the control parameters of the network-building converter according to a preset self-adaptive gain adjustment model. And dynamically updating parameters of the PID controller or the PI controller, and adjusting a control signal used for controlling the output voltage and the output current of the network construction type converter in real time, so that the output voltage and the output current of the network construction type converter are controlled to be stable. The parameters of the PID controller or the PI controller are dynamically adjusted, and the control signal is adjusted in real time based on the adjusted parameters, so that the stability of the output current and the output voltage of the grid-forming converter can be ensured, and the stability of the grid-forming converter in a power grid is ensured; the technical problem that in the prior art, an effective technical means for conducting self-adaptive adjustment on the control parameters of the network building converter to maintain stable operation of a power grid system is lacked is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of power systems, and in particular to a method and device for adaptively adjusting control parameters of a grid-connected converter. Background Art

[0002] The grid-forming inverter (GFI), as a device that simulates the inertia of a synchronous machine, maintains the stability of the power grid by controlling the voltage and frequency. In order to understand its dynamic behavior under disturbances, a small signal model is usually used to perform linear analysis of the system. The purpose of the small signal model is to study how the system responds under conditions such as grid disturbances or load changes. Usually, in small signal analysis, it is assumed that the system is subjected to small disturbances near a certain stable operating point, and by linearizing the control system, a set of transfer functions is obtained to describe the dynamic characteristics of the system. At present, how to adaptively adjust the control parameters of the grid-forming inverter to ensure that the grid-forming inverter responds quickly and oscillates in the power grid system and achieves stable operation of the power grid system is still a technical problem that needs to be solved urgently by those skilled in the art. Summary of the Invention

[0003] The present invention provides a method and device for adaptively adjusting the control parameters of a grid-connected converter, which are used to solve the technical problem that the prior art lacks effective technical means for adaptively adjusting the control parameters of the grid-connected converter to maintain stable operation of the power grid system.

[0004] In view of this, a first aspect of the present invention provides a method for adaptively adjusting control parameters of a grid-connected converter, comprising:

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

[0006] Obtain the output current and output voltage of the grid-connected converter in real time;

[0007] According to the output current and output voltage of the grid-type converter, the current disturbance and voltage disturbance of the grid-type converter are calculated based on the small signal model;

[0008] Based on the current disturbance and voltage disturbance of the grid-type 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 the PI controller, the control signal for controlling the output voltage and output current of the grid-type converter is adjusted in real time, so that the output voltage and output current of the grid-type converter are stabilized.

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

[0011] Optionally, the model of the current control loop is:

[0012]

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

[0014] Optionally, the voltage control loop model is:

[0015]

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

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

[0018]

[0019] in, is the transfer function of the grid connection point, is the grid voltage, is the grid current, s is the complex variable in Laplace transform, is the equivalent impedance of the grid connection point, is the grid connection point characteristic matrix.

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

[0021]

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

[0023] Optionally, the current gain adjustment step size is calculated as:

[0024]

[0025] in, is the current adaptive gain, is the current disturbance at time t.

[0026] Optionally, the voltage gain adjustment step length is calculated as:

[0027]

[0028] in, is the voltage adaptive gain, is the voltage disturbance at time t.

[0029] A second aspect of the present invention provides a device for adaptively adjusting control parameters of a grid-connected converter, comprising:

[0030] Small signal model building module, used to build the small signal model of the grid-connected converter;

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

[0032] A 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] A 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 according to a preset adaptive gain adjustment model;

[0034] The control module is used to adjust the control signal for controlling the output voltage and output current of the grid-type converter in real time based on the updated parameters of the PID controller or the PI controller, so that the output voltage and output current of the grid-type converter are stable.

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

[0036]

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

[0038] From the above technical solutions, it can be seen that the method for adaptively adjusting the control parameters of the grid-connected converter provided by the present invention has the following advantages:

[0039] The present invention provides a method for adaptively adjusting control parameters of a grid-type converter, which monitors the output current and output voltage of the grid-type converter in real time, calculates voltage and current disturbances based on a small signal model of the grid-type converter, and then dynamically updates the parameters of a PID controller or a PI controller based on a preset adaptive gain adjustment model. Based on the updated parameters of the PID controller or the PI controller, the method adjusts the control signal used to control the output voltage and output current of the grid-type converter in real time, thereby stabilizing the output voltage and output current of the grid-type 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 ensures the stability of the output current and output voltage of the grid-type converter, effectively ensuring the stability of the grid-type converter in the power grid, and solving the technical problem of the prior art lacking an effective technical means for adaptively adjusting the control parameters of the grid-type converter to maintain the stable operation of the power grid system. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying any creative work.

[0041] Figure 1 Schematic diagram of a flow chart of a method for adaptively adjusting control parameters of a grid-connected converter provided in an embodiment of the present invention;

[0042] Figure 2 The present invention provides a schematic structural diagram of a device for adaptively adjusting control parameters of a grid-connected converter according to an embodiment of the present invention. DETAILED DESCRIPTION

[0043] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0044] For easier understanding, see Figure 1 The present invention provides an embodiment of a method for adaptively adjusting control parameters of a grid-connected converter, comprising:

[0045] Step 101: Construct a small signal model of a grid-connected converter.

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

[0047] The main function of the current control loop is to achieve power control by adjusting the output current of the converter. In small signal analysis, the current control loop can be modeled as a transfer function. Set the reference current to , the actual output current is , the gain of the current control loop is The state space equation of the current control loop is:

[0048]

[0049]

[0050] in, for The first derivative with respect to time t, is the state matrix of the current control loop, which is used to describe the dynamic characteristics of the state variables of the current control loop (such as inductor current) changing with time. is the input matrix of the current control loop, which is used to represent the contribution of the input signal (such as the current reference signal) to the change of the state variable. is the output matrix of the current control loop, which is used to map the state variables to the output signals (such as the actual current output). is the direct transfer matrix of the current control loop, which is used to represent the path from the input signal directly to the output (usually 0 or a minimum value). is the state variable of the current control loop, is the input signal, is the current output signal.

[0051] Through small signal linearization, the transfer function of the current control loop can be obtained as:

[0052]

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

[0054] The task of the voltage control loop is to maintain the output voltage of the converter stable. The dynamic behavior of the voltage control loop can be determined by the reference voltage. The actual output voltage The error between them can be 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, is the state matrix of the voltage control loop, which is used to describe the dynamic characteristics of the state variables of the voltage control loop (such as capacitor voltage). is the input matrix of the voltage control loop, which is used to represent the influence of the input signal (such as the voltage reference signal or the current control loop output) on the state variable. is the output matrix of the voltage control loop, which is used to map the state variables to the output voltage signal. is the direct transfer matrix of the voltage control loop, which is used to represent the path from the input signal directly to the output. is the state variable of the voltage control loop, is the input signal (such as reference voltage), It is the voltage output signal.

[0058] Through small signal linearization, the transfer function of the current control loop can be obtained as:

[0059]

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

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

[0062]

[0063]

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

[0065]

[0066] in, is the transfer function of the grid connection point, is the grid voltage, is the grid current, s is the complex variable in Laplace transform, is the equivalent impedance of the grid connection point, is the grid connection point characteristic matrix.

[0067] The overall system of the grid-connected converter consists of the interaction between the current control loop, the voltage control loop, and the grid connection point. By combining the state space models of the current control loop, the voltage control loop, and the grid connection point, the state space model of the entire system can be obtained. Assume that the state vector of the system is , the input vector is , the output vector is , the state space model of the entire system is:

[0068]

[0069]

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

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

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

[0073] Step 103 : Calculate the current disturbance and voltage disturbance of the grid-type converter based on the small signal model according to the output current and output voltage of the grid-type converter.

[0074] It should be noted that in order to perform 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 that the equilibrium state vector of the system is , represents 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 , is the input vector of the system equilibrium point, which represents the steady-state value of the input signal. The disturbance of the output signal is , is the system equilibrium point output vector, representing the steady-state value of the output signal. Expanding it, we get the small signal model of the system:

[0075]

[0076]

[0077] in, is the small signal disturbance of the state variable, for The first derivative of is the state matrix, which is used to describe the dynamic coupling relationship between state variables (composed of the Jacobian matrices of the current loop, voltage loop, and grid connection model). is the input matrix, which is used to describe the influence of the input signal on the state variable (such as the driving effect of the reference current / voltage on the state change). is the output matrix, which is used to describe the mapping relationship between state variables and output signals (such as how the grid voltage / current is derived from the state variables). is the direct transfer matrix, which is used to describe the direct transfer relationship from input signal to output signal (usually it can be ignored in small signal models, that is, D≈0).

[0078] The total transfer function of a system is the combination of the transfer functions of all its links. Transfer functions can be used to analyze the stability of a system. Eigenvalue analysis examines the system's poles. If all poles lie in the left half of the complex plane, the system is stable. If any poles lie in the right half plane, the system is unstable.

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

[0080]

[0081] in, is the determinant calculation, I is the identity matrix, s is the eigenvalue of the state matrix A (i.e., the pole of the system), which can be calculated by linear algebra.

[0082] Solving the characteristic equation yields the poles of the system. If all poles have negative real parts, the system is stable. If any pole has a positive real part, 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 the PI controller according to a 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, is the scale parameter, is the integration parameter, is the differential parameter, and s is the complex variable in the Laplace transform.

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

[0089]

[0090] in, is the scale parameter, is the integration parameter, and s is the complex variable in the Laplace transform.

[0091] By adjusting 、 and The value of can change the response speed and steady-state error of the system, so that the system remains stable at the grid connection point.

[0092] The parameters of the PID controller or PI controller are adjusted through adaptive algorithms to maintain the real-time stability of the system. This usually involves real-time monitoring of the system status (such as frequency, load, voltage, etc.) and dynamically adjusting the controller 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 disturbances ), the gain of the current control loop can be determined.

[0094] The goal of the adaptive algorithm is to dynamically adjust the gain To ensure the stability of the current control loop. The goal of this gain adjustment is to control the pole position of the system in the left half plane. The following adaptive algorithm can be used to adjust :

[0095]

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

[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, is the voltage adaptive gain, which controls the adjustment rate of the voltage gain. is the voltage disturbance at time t. According to the response of the system, the gain It will change over time and dynamically adjust the control performance.

[0100] Designing adaptive functions for:

[0101]

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

[0103]

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

[0105] If you adjust the gain according to the current system status and , so that the adaptive function of the system Keep decreasing, then the system can be guaranteed to be stable. Specifically, the gain adjustment equation is:

[0106]

[0107] According to the feedback signal of the system (current error, voltage error, etc.), the adaptive gain can be dynamically updated:

[0108]

[0109] in, is the gain of the current control loop at time t, is the gain of the current control loop at time t-1, is the current gain adjustment step size, is the gain of the voltage control loop at time t.

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

[0111]

[0112] in, is the current adaptive gain, is the current disturbance at time t.

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

[0114]

[0115] in, is the voltage adaptive gain, is the voltage disturbance at time t.

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

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

[0118] To more specifically illustrate the implementation of the method for adaptively adjusting the control parameters of a grid-connected converter provided in an embodiment of the present invention, a specific application example is provided below for illustration:

[0119] Assume that the initial gain of the current control loop is , the initial gain of the voltage control loop is , the current adaptive gain is , the voltage adaptive gain is , the current deviation is , voltage deviation . Use the following formula to adjust the gain:

[0120]

[0121] The new value after gain adjustment is:

[0122]

[0123] According to this algorithm, the gains of the PID controller / PI controller are adjusted in real time, so that the system can adapt to the dynamic changes of the power grid and maintain stability.

[0124] The present invention provides a method for adaptively adjusting control parameters of a grid-type converter, which monitors the output current and output voltage of the grid-type converter in real time, calculates voltage and current disturbances based on a small signal model of the grid-type converter, and then dynamically updates the parameters of a PID controller or a PI controller based on a preset adaptive gain adjustment model. Based on the updated parameters of the PID controller or the PI controller, the method adjusts the control signal used to control the output voltage and output current of the grid-type converter in real time, thereby stabilizing the output voltage and output current of the grid-type 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 ensures the stability of the output current and output voltage of the grid-type converter, effectively ensuring the stability of the grid-type converter in the power grid, and solving the technical problem of the prior art lacking an effective technical means for adaptively adjusting the control parameters of the grid-type converter to maintain the stable operation of the power grid system.

[0125] For easier understanding, see Figure 2 The present invention provides an embodiment of a device for adaptively adjusting control parameters of a grid-connected converter, comprising:

[0126] Small signal model building module, used to build the small signal model of the grid-connected converter;

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

[0128] A 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] A 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 according to a preset adaptive gain adjustment model;

[0130] The control module is used to adjust the control signal for controlling the output voltage and output current of the grid-type converter in real time based on the updated parameters of the PID controller or the PI controller, so that the output voltage and output current of the grid-type converter are stable.

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

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

[0133]

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

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

[0136]

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

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

[0139]

[0140] in, is the transfer function of the grid connection point, is the grid voltage, is the grid current, s is the complex variable in Laplace transform, is the equivalent impedance of the grid connection point, is the grid connection point characteristic matrix.

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

[0142]

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

[0144] In one embodiment, the current gain adjustment step length is calculated as follows:

[0145]

[0146] in, is the current adaptive gain, is the current disturbance at time t.

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

[0148]

[0149] in, is the voltage adaptive gain, is the voltage disturbance at time t.

[0150] The grid-connected converter control parameter adaptive adjustment device provided in the present invention is used to execute the grid-connected converter control parameter adaptive adjustment method provided in the present invention. Its technical effects have been described in the embodiment of the grid-connected converter control parameter adaptive adjustment method provided in the present invention and will not be repeated here.

[0151] The terms "first," "second," "third," and the like in the present invention are used to distinguish similar objects and are not necessarily used to describe a particular order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of the present invention described herein can, for example, be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having," and any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus comprising 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] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that the technical solutions described in the above embodiments can still be modified, or some of the technical features thereof can be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for adaptively adjusting control parameters of a grid-connected converter, characterized in that: include: Construct a small signal model of a grid-connected converter; Obtain the output current and output voltage of the grid-connected converter in real time; According to the output current and output voltage of the grid-type converter, the current disturbance and voltage disturbance of the grid-type converter are calculated based on the small signal model; Based on the current disturbance and voltage disturbance of the grid-type 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 the PI controller, the control signal for controlling the output voltage and output current of the grid-type converter is adjusted in real time, so that the output voltage and output current of the grid-type converter are stabilized.

2. The method for adaptively adjusting control parameters of a grid-connected converter according to claim 1, characterized in that: The small signal model of the 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.

3. The method for adaptively adjusting control parameters of a grid-connected converter according to claim 2, characterized in that: The model of the current control loop is: in, is the transfer function of the current control loop, is the actual output current, is the reference current, is the gain of the current control loop, is the time constant of the current control loop, and s is the complex variable in the Laplace transform.

4. The method for adaptively adjusting control parameters of a grid-connected converter according to claim 2, wherein: The model of the voltage control loop is: in, is the transfer function of the voltage control loop, is the actual output current, is the reference voltage, is the gain of the voltage control loop, is the time constant of the voltage control loop, and s is the complex variable in the Laplace transform.

5. The method for adaptively adjusting control parameters of a grid-connected converter according to claim 2, wherein: The state space model of the grid connection point is: in, is the transfer function of the grid connection point, is the grid voltage, is the grid current, s is the complex variable in Laplace transform, is the equivalent impedance of the grid connection point, is the grid connection point characteristic matrix.

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

7. The method for adaptively adjusting control parameters of a grid-connected converter according to claim 6, characterized in that: The calculation formula for the current gain adjustment step size is: in, is the current adaptive gain, is the current disturbance at time t.

8. The method for adaptively adjusting control parameters of a grid-connected converter according to claim 6, characterized in that: The calculation formula for the voltage gain adjustment step size is: in, is the voltage adaptive gain, is the voltage disturbance at time t.

9. A device for adaptively adjusting control parameters of a grid-connected converter, characterized in that: include: Small signal model building module, used to build the small signal model of the grid-connected converter; An acquisition module is used to obtain the output current and output voltage of the grid-type converter in real time; A 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; A 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 according to a preset adaptive gain adjustment model; The control module is used to adjust the control signal for controlling the output voltage and output current of the grid-type converter in real time based on the updated parameters of the PID controller or the PI controller, so that the output voltage and output current of the grid-type converter are stable.

10. The device for adaptively adjusting control parameters of a grid-connected converter according to claim 9, characterized in that: The preset adaptive gain adjustment model is: in, is the gain of the current control loop at time t, is the gain of the current control loop at time t-1, is the current gain adjustment step size, is the gain of the voltage control loop at time t, is the gain of the voltage control loop at time t-1, Adjust the step size for the voltage gain.

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