Self-adaptive damping multi-machine resonance suppression method for large-scale off-grid optical hydrogen storage system

Abstract

The invention discloses a self-adaptive damping multi-machine resonance suppression method for a large-scale off-grid optical hydrogen storage system, and the method comprises the steps: 1, sampling a bridge arm side inductive current, and subtracting the bridge arm side inductive current from a given signal to obtain an error signal; 2, performing sliding mode control on the error signal to obtain an output signal; 3, enabling the output signal to pass through a damping adjusting unit to obtain a modulation signal; 4, damping self-adaptive adjustment is carried out according to different working conditions of multi-machine parallel connection; and 5, sending the modulation signal to a space vector modulation unit, and outputting a pulse driving signal of each switching device. According to the method, the problem of multi-machine resonance of the current loop of the grid-following inverter can be solved, the dynamic response is improved while stable operation of the system is ensured, and the method has important theoretical significance and practical value.

Description

Technical Field

[0001] The invention relates to an adaptive damping multi-machine resonance suppression method for a large-scale off-grid solar hydrogen storage system, and belongs to the field of control of green hydrogen production systems using renewable energy. Background Art

[0002] Hydrogen is an ideal clean energy with green and high calorific value, suitable for long-term storage and mobility. Large-scale photovoltaic hydrogen production can improve the utilization rate of photovoltaic power and effectively solve the intermittent problem of photovoltaic power generation. The hydrogen production system is divided into two types: grid-connected and off-grid according to whether it is connected to the power grid. The disadvantage of the grid-connected hydrogen production system is that it relies on the power grid, and the phase-controlled rectifier device will introduce a large number of harmonics to the power grid. The overall solution does not obtain truly clean "green hydrogen"; the off-grid structure is completely separated from the power grid, and the photovoltaic array and energy storage are mainly used to power the electrolyzer, which can effectively avoid the adverse effects of the system on the power grid harmonics. In large-scale photovoltaic hydrogen production projects, the capacity of a single inverter is difficult to meet the needs of large-scale hydrogen production. The AC microgrid system composed of multiple inverters in parallel has become a trend in the application of large-scale hydrogen production in distributed power generation.

[0003] In a distributed hydrogen production AC microgrid, a grid-type energy storage inverter is networked, and a grid-type photovoltaic inverter is connected to the microgrid. When multiple photovoltaic inverters work in parallel, the output side of the inverter bridge is usually connected to an LCL filter, which leads to ① a fixed resonance with a higher frequency in the system, the frequency of which is determined by the inverter's own parameters; ② another resonance that is affected by the interaction of the inverters and moves to a low frequency as the number of inverters increases. Therefore, it is crucial to enhance the robustness of the grid-type inverter at low frequencies and reduce the sensitivity of the control loop to parameter changes for the stable operation of multiple machines in parallel. However, the existing grid-type inverters mostly use power outer loop + current inner loop control, and their robustness cannot meet the requirements.

[0004] From the resonance mechanism of the single grid inverter, it can be seen that the main reason for the resonance of the system is that the LCL filter has inherent resonance as a third-order underdamped system. Therefore, the resonance can be suppressed by increasing the system damping at the resonance in an appropriate way. The passive damping method of the filter capacitor in parallel with the resistor has the disadvantage of large power loss and is difficult to be used in practice. The active damping method of capacitor current proportional feedback is widely used because of its obvious resonance damping effect. However, it has the problem of relying on sampling accuracy and lacking the flexibility of damping adjustment, which makes it difficult to directly apply it under multi-machine resonance conditions.

[0005] Therefore, it is of great significance to study the multi-machine resonance optimization control strategy in distributed hydrogen production AC microgrid. Summary of the invention

[0006] In view of the deficiencies of the prior art mentioned above, the present invention proposes an adaptive damping multi-machine resonance suppression method for a large-scale off-grid solar hydrogen storage system, in order to enhance the robust performance of the current loop through sliding mode variable structure control to weaken the influence of the mutual coupling of multi-machine resonances, and adopt fuzzy control to adaptively adjust the active damping to improve the dynamic response, thereby ensuring the stable operation of the grid-following inverter and the requirement that the total harmonic distortion is less than 5%.

[0007] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme:

[0008] The method for suppressing multi-machine resonance of an adaptive damping system for large-scale off-grid hydrogen storage system of the present invention is characterized in that it comprises the following steps:

[0009] Step 1: Use equation (1) to establish the sufficient condition for the stability of the sliding mode control of the zth LCL three-level grid-following inverter:

[0010] (1)

[0011] In formula (1), is the tracking error function of the inductor current on the bridge arm side of the zth LCL three-level grid-following inverter, and is obtained by equation (2): is the derivative of the tracking error function of the inductor current on the bridge arm side of the z-th LCL three-level grid-following inverter:

[0012] (2)

[0013] In formula (2), is a differential operator; is the extreme point of sliding mode control; represents the order of differentiation; represents the inductor current deviation of the bridge arm side of the zth LCL three-level grid-following inverter, and is obtained by formula (3):

[0014] (3)

[0015] In formula (3), is the inductor current on the bridge arm side of the zth LCL-type three-level grid-following inverter; is the output current given value of the zth LCL three-level grid-following inverter;

[0016] Step 2: Determine whether equation (1) holds true. If true, it means that the zth LCL three-level grid-connected inverter is stable. Otherwise, it means that the zth LCL three-level grid-connected inverter is unstable, and execute step 3.

[0017] Step 3: According to the operating conditions of the large-scale off-grid solar hydrogen storage system, the active damping weight factor of the zth LCL three-level grid-following inverter is Performing adaptive adjustment for adaptive active damping control of the zth LCL type three-level grid-following inverter;

[0018] Step 4: Use equation (4) to obtain the control signal of the zth LCL three-level grid-following inverter: :

[0019] (4)

[0020] In formula (4), is the robustness coefficient of the zth LCL three-level grid-following inverter, is the exponential approach term coefficient of the zth LCL three-level grid-following inverter, and sat is the saturation function; is the capacitor current of the zth LCL three-level grid-following inverter;

[0021] Step 5: Right After Clarke inverse transformation, a three-phase modulation signal is obtained, and combined with the SVPWM modulation strategy, a pulse drive signal of the switching device is output to suppress the resonance of the zth LCL three-level grid-following inverter.

[0022] The adaptive damping multi-machine resonance suppression method for a large-scale off-grid solar hydrogen storage system described in the present invention is also characterized in that step 3 includes the following steps:

[0023] Step 3.1: Fuzzification:

[0024] Set the number of grid-connected inverters planned to be in long-term operation to M, and the number of grid-connected inverters temporarily put into operation / removed to N;

[0025] The domain of M is [0, m], and the domain of N is [-n, n], where m is the maximum number of grid-following inverters planned to be put into operation, and n is the maximum number of grid-following inverters that need to be temporarily put into operation / cut off. A positive value of n indicates putting into operation, and a negative value of n indicates cutting off.

[0026] Pick The domain of is [0, ];in, is the active damping limit value;

[0027] According to M, N, and The domain of discourse is divided into M, N, and The K fuzzy subsets of M are obtained accordingly. , the fuzzy set of N is , The fuzzy sets are , where , and respectively represent the k-th fuzzy subsets of M, N, and ;

[0028] Step 3.2: Fuzzy inference:

[0029] The operating conditions of the large-scale off-grid photovoltaic-hydrogen storage system are divided into stable conditions and unstable conditions;

[0030] Under stable conditions, when M < (m / 2) and N < 0, take the active damping weight factor to improve the dynamic response rate of the z-th LCL-type three-level grid-following inverter;

[0031] Under unstable conditions, when M ≥ (m / 2) and N ≥ 0, take the active damping weight factor to weaken the resonance peak of the z-th LCL-type three-level grid-following inverter;

[0032] When M belongs to the r-th fuzzy subset in its fuzzy set, and N belongs to the j-th fuzzy subset in its fuzzy set, the corresponding fuzzy output is denoted as , thus constructing a fuzzy inference relationship, including:

[0033] If r ≥ (K / 2) or j ≥ (K / 2), and r > j, take the (K - r + 1)-th fuzzy subset in the fuzzy set of

[0034] If r ≥ (K / 2) or j ≥ (K / 2), and r < j, take the (K - j + 1)-th fuzzy subset in the fuzzy set of

[0035] If r < (K / 2) and j < (K / 2), and r > j, take the (K - r + 1)-th fuzzy subset in the fuzzy set of

[0036] If r < (K / 2) and j < (K / 2), and r < j, take the (K - j + 1)-th fuzzy subset in the fuzzy set of

[0037] Step 3.3: For the fuzzy output Defuzzification is performed to obtain the accurate active damping weight factor of the zth LCL three-level grid-following inverter. .

[0038] An electronic device of the present invention includes a memory and a processor, wherein the memory is used to store a program that supports the processor to execute the adaptive damping multi-machine resonance suppression method, and the processor is configured to execute the program stored in the memory.

[0039] The present invention provides a computer-readable storage medium, wherein a computer program is stored on the computer-readable storage medium, and the computer program executes the steps of the adaptive damping multi-machine resonance suppression method when the computer program is run by a processor.

[0040] Compared with the prior art, the present invention has the following beneficial effects:

[0041] 1. The present invention uses sliding mode variable structure control based on improving the robust performance of the system, which enhances the robust performance of the current loop of the grid-following inverter and reduces the sensitivity of the control loop to parameter changes; thereby effectively suppressing the noise component in the AC signal and improving the fidelity of the power frequency signal.

[0042] 2. The present invention achieves the effect of suppressing resonance and adaptive regulation by applying fuzzy control to the active damping control loop. Compared with the traditional active damping control loop, the requirement for sampling accuracy can be reduced; thereby ensuring that the large-scale off-grid solar hydrogen storage system can maintain stable output when the operating conditions change, improving its response speed and dynamic performance, reducing the risk of system instability caused by parameter mismatch or environmental changes, helping to reduce energy consumption, and improving the energy efficiency level of the overall system.

[0043] 3. The present invention simplifies the complex controller expression of traditional SMC by combining SMC with active damping, reduces the interference of noise on the controller, and limits the amplitude of jitter; thereby solving the problem of multi-machine resonance of the current loop in multiple grid-connected inverters in large-scale off-grid solar hydrogen storage systems, increasing the stability margin of the grid-connected inverter in the microgrid, and promoting the widespread and reliable application of LCL filtered three-level grid-connected inverters, which has important theoretical significance and practical value. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 This is a diagram of the architecture of a large-scale off-grid solar hydrogen storage system in an implementation example of the present invention;

[0045] Figure 2 It is a schematic diagram of a multi-machine parallel structure of a three-level inverter connected to a grid in an implementation example of the present invention;

[0046] Figure 3 It is the control loop model diagram of the three-level inverter;

[0047] Figure 4 This is the three-phase grid-following current waveform of traditional QPR control under multi-machine working conditions;

[0048] Figure 5 This is the three-phase grid-following current waveform diagram of traditional QPR control + active damping under multi-machine working conditions;

[0049] Figure 6 This is the grid current THD diagram of traditional QPR control + active damping under multi-machine conditions;

[0050] Figure 7 The three-phase grid current waveform of SMC+active damping under multi-machine working condition;

[0051] Figure 8 This is the grid current THD diagram of SMC+active damping under multi-machine conditions;

[0052] Fig. 9 The three-phase grid current waveform of SMC+active damping when the LCL parameter is attenuated by 30%;

[0053] Fig.10 This is the grid current THD diagram of SMC+active damping when the LCL parameter is attenuated by 30%. DETAILED DESCRIPTION

[0054] In this embodiment, in order to solve Figure 1 In order to solve the instability problem caused by resonance under the condition of multiple grid-following inverters in parallel in the large-scale off-grid solar hydrogen storage system shown in the figure, an adaptive damping multi-machine resonance suppression method for large-scale off-grid solar hydrogen storage system is proposed. First, sufficient conditions for the stability of sliding mode control are established, and the sliding mode surface and the convergence law are designed; secondly, the expression of the current control outer loop is derived in combination with the circuit state equation, the expression is simplified and the stability analysis is performed; then, according to the fuzzy control theory and the different working conditions of multiple machines (the switching of grid-following inverters), fuzzy rules are designed, fuzzy logic reasoning and defuzzification are performed to achieve adaptive adjustment of active damping; finally, Clarke inverse transform is performed to obtain the three-phase modulation wave, and combined with the SVPWM modulation strategy, the actual output of the three-phase inverter is realized to achieve the purpose of suppressing resonance, stabilizing the system and enhancing the robustness of the system. Specifically, the method includes:

[0055] Step 1: Use equation (1) to establish the sufficient condition for the stability of the sliding mode control of the zth LCL three-level grid-following inverter:

[0056] (1)

[0057] In formula (1), is the tracking error function of the inductor current on the bridge arm side of the zth LCL three-level grid-following inverter, and is obtained by equation (2): is the derivative of the tracking error function of the inductor current on the bridge arm side of the z-th LCL three-level grid-following inverter:

[0058] (2)

[0059] In formula (2), is a differential operator; is the extreme point of sliding mode control; represents the order of differentiation; represents the inductor current deviation of the bridge arm side of the zth LCL three-level grid-following inverter, and is obtained by formula (3):

[0060] (3)

[0061] In formula (3), is the inductor current on the bridge arm side of the zth LCL-type three-level grid-following inverter; is the output current given value of the zth LCL three-level grid-following inverter;

[0062] by For example, design the following sliding die surface:

[0063] (4)

[0064] In formula (4), are the sliding surfaces of the α-axis and the β-axis respectively; , are the inductor current errors on the bridge arm side of the α-axis and β-axis respectively; are the first-order derivatives of the inductor current errors on the bridge arm sides of the α-axis and β-axis, respectively; are the second-order derivatives of the inductor current errors on the α-axis and β-axis bridge arm sides, respectively; and are the sliding surface coefficients of the α-axis and β-axis respectively. The sliding surface coefficients are required to satisfy the Hurwitz condition to ensure that the error can converge to zero along the designed sliding surface motion trajectory after the system reaches the sliding surface.

[0065] The Hurwitz condition is expressed as follows: First, write the polynomial corresponding to the sliding surface:

[0066] (5)

[0067] In formula (5), p is the Laplace operator. The stability of the system requires that the poles of the characteristic equation are located in the left half plane of the complex plane, that is, the real part of the solution in formula (5) is required to be negative.

[0068] Select the reaching law as follows:

[0069] (6)

[0070] In formula (6), are the robust term coefficients of the α-axis and β-axis, respectively, and their magnitudes affect the anti-interference ability of the system. are the reaching law coefficients of the α-axis and the β-axis respectively, and their magnitudes determine how fast the control system reaches the sliding surface; the definition of the sat(S) function is as follows:

[0071] (7)

[0072] In formula (7) It is the smoothing term coefficient. Using sat(S) function instead of sign(S) in conventional sliding mode control can reduce the amplitude of vibration and eliminate vibration when the system interference is low.

[0073] This example takes two grid-following inverters as an example to establish the circuit model of the three-level grid-following inverter. Figure 2 As shown, the differential equation of the three-level inverter circuit is established:

[0074] (8)

[0075] (9)

[0076] (10)

[0077] In the formula, and They are the inverter three-phase output voltage and the inductor current flowing through the bridge arm side respectively; is the voltage of the inverter filter capacitor; L and R L are the inductance and resistance of the inductor on the bridge arm side respectively.

[0078] Rewrite the circuit equation and perform Clarke transformation:

[0079] (11)

[0080] Combining equations (4), (6), (7) and (11), we can derive the sliding mode controller of the three-level grid-following inverter:

[0081] (12)

[0082] Considering the differential term amplifying the noise, the sliding mode controller is simplified by combining the specific implementation parameters:

[0083] (13).

[0084] Step 2: Determine whether formula (1) is established. If established, it means that the zth LCL type three-level grid-connected inverter is stable; otherwise, it means that the zth LCL type three-level grid-connected inverter is unstable, and execute step 3;

[0085] Step 3: Define the active damping weight factor for adjusting the zth LCL three-level grid-following inverter , and based on the operating conditions of large-scale off-grid solar hydrogen storage systems, Adaptive adjustment is performed to perform adaptive active damping control on the zth LCL three-level grid-following inverter:

[0086] Step 3.1: Fuzzification:

[0087] Set the number of grid-connected inverters planned to be in long-term operation to M, and the number of grid-connected inverters temporarily put into operation / removed to N;

[0088] The domain of M is [0, m], and the domain of N is [-n, n], where m is the maximum number of grid-following inverters planned to be put into operation, and n is the maximum number of grid-following inverters that need to be temporarily put into operation / cut off. A positive value of n indicates putting into operation, and a negative value of n indicates cutting off.

[0089] Pick The domain of is [0, ];in, is the active damping limit value; in this embodiment, .

[0090] According to M, N, and The domain of discourse is divided into M, N, and The K fuzzy subsets of M are obtained accordingly. , the fuzzy set of N is , The fuzzy set is ,in, , and Represents M, N, and The kth fuzzy subset of .

[0091] Step 3.2: Fuzzy reasoning:

[0092] The operating conditions of large-scale off-grid solar hydrogen storage systems are divided into stable conditions and unstable conditions;

[0093] Under stable conditions, when M<(m / 2) and N<0, the active damping weight factor is , in order to improve the dynamic response rate of the zth LCL type three-level grid-following inverter;

[0094] Under unstable operating conditions, when M ≥ (m / 2) and N ≥ 0, take the active damping weight factor , to weaken the resonance peak of the z-th LCL-type three-level grid-connected inverter;

[0095] When M belongs to the r-th fuzzy subset of its fuzzy set , and N belongs to the j-th fuzzy subset of its fuzzy set , the corresponding fuzzy output is denoted as , thus constructing a fuzzy inference relationship, including:

[0096] If r ≥ (K / 2) or j ≥ (K / 2), and r > j, Take the (K - r + 1)-th fuzzy subset of the fuzzy set of ;

[0097] If r ≥ (K / 2) or j ≥ (K / 2), and r < j, Take the (K - j + 1)-th fuzzy subset of the fuzzy set of ;

[0098] If r < (K / 2) and j < (K / 2), and r > j, Take the (K - r + 1)-th fuzzy subset of the fuzzy set of ;

[0099] If r < (K / 2) and j < (K / 2), and r < j, Take the (K - j + 1)-th fuzzy subset of the fuzzy set of ;

[0100] The fuzzy rules of this embodiment are shown in Table 1:

[0101] Table 1

[0102]

[0103] Step 3.3: Defuzzify the fuzzy output to obtain the accurate active damping weight factor of the z-th LCL-type three-level grid-connected inverter .

[0104] Step 4: Use Equation (14) to obtain the control signal of the z-th LCL-type three-level grid-connected inverter :

[0105] (14)

[0106] In Equation (15), is the robustness coefficient of the zth LCL three-level grid-following inverter, is the exponential approach term coefficient of the zth LCL three-level grid-following inverter, and sat is the saturation function; is the capacitor current of the zth LCL three-level grid-following inverter.

[0107] Step 5: After Clarke inverse transformation, a three-phase modulation signal is obtained, and combined with the SVPWM modulation strategy, a pulse drive signal of the switching device is output to suppress the resonance of the zth LCL three-level grid-following inverter. The final control block diagram is shown in Figure 3 shown.

[0108] The main parameters in this embodiment are shown in Table 2:

[0109] Table 2

[0110]

[0111] In this embodiment, an electronic device includes a memory and a processor, wherein the memory is used to store a program that supports the processor to execute the above method, and the processor is configured to execute the program stored in the memory.

[0112] In this embodiment, a computer-readable storage medium stores a computer program on the computer-readable storage medium, and the computer program executes the steps of the above method when executed by a processor.

[0113] In order to illustrate the multi-machine resonance suppression effect of the method proposed in the present invention, the multi-machine resonance suppression effects of the traditional QPR, the traditional QPR + active damping and the method proposed in the present invention are analyzed by simulation. This example takes two three-level grid-following inverters as an example. Figure 4 This is the three-phase grid-following current waveform of traditional QPR control under multi-machine working conditions. The system is unstable and the current waveform diverges; Figure 5 This is the three-phase grid-following current waveform of traditional QPR control + active damping under multi-machine working conditions. The system is stable, but the current distortion is serious; Figure 6 This is the grid current THD diagram of traditional QPR control + active damping under multi-machine conditions, with a THD of 11.12%; Figure 7 The three-phase grid-following current waveform of the method proposed in the present invention has a stable system and good waveform quality; Figure 8 This is the grid current THD diagram of the method proposed in the present invention, and the THD is 0.55%; Fig. 9 The three-phase grid current waveform of the method proposed by the present invention when the parameters are pinched (LCL parameters are simultaneously attenuated by 30%), the system is stable, and the waveform quality is good; Fig.10The following grid current THD diagram of the method proposed by the present invention when the parameters are adjusted, the THD is 0.56%. The above proves the effectiveness of the method proposed by the present invention in suppressing multi-machine resonance.

Claims

1. An adaptive damping multi-machine resonance suppression method for a large-scale off-grid solar hydrogen storage system, characterized in that: The following steps are involved: Step 1: Use equation (1) to establish the sufficient condition for the stability of the sliding mode control of the zth LCL three-level grid-following inverter: (1) In formula (1), is the tracking error function of the inductor current on the bridge arm side of the zth LCL three-level grid-following inverter, and is obtained by equation (2): is the derivative of the tracking error function of the inductor current on the bridge arm side of the z-th LCL three-level grid-following inverter: (2) In formula (2), is a differential operator; is the extreme point of sliding mode control; represents the order of differentiation; represents the inductor current deviation of the bridge arm side of the zth LCL three-level grid-following inverter, and is obtained by formula (3): (3) In formula (3), is the inductor current on the bridge arm side of the zth LCL-type three-level grid-following inverter; is the output current given value of the zth LCL three-level grid-following inverter; Step 2: Determine whether equation (1) holds true. If true, it means that the zth LCL three-level grid-connected inverter is stable. Otherwise, it means that the zth LCL three-level grid-connected inverter is unstable, and execute step 3. Step 3: According to the operating conditions of the large-scale off-grid solar hydrogen storage system, the active damping weight factor of the zth LCL three-level grid-following inverter is Performing adaptive adjustment for adaptive active damping control of the zth LCL three-level grid-following inverter; Step 4: Use equation (4) to obtain the control signal of the zth LCL three-level grid-following inverter: : (4) In formula (4), is the robustness coefficient of the zth LCL three-level grid-following inverter, is the exponential approach term coefficient of the zth LCL three-level grid-following inverter, and sat is the saturation function; is the capacitor current of the zth LCL three-level grid-following inverter; Step 5: Right After Clarke inverse transformation, a three-phase modulation signal is obtained, and combined with the SVPWM modulation strategy, a pulse drive signal of the switching device is output to suppress the resonance of the zth LCL three-level grid-following inverter.

2. According to claim 1, the adaptive damping multi-machine resonance suppression method for a large-scale off-grid solar hydrogen storage system is characterized in that: Step 3 includes the following steps: Step 3.1: Fuzzification: Set the number of grid-connected inverters planned to be in long-term operation to M, and the number of grid-connected inverters temporarily put into operation / removed to N; The domain of M is [0, m], and the domain of N is [-n, n], where m is the maximum number of grid-following inverters planned to be put into operation, and n is the maximum number of grid-following inverters that need to be temporarily put into operation / cut off. A positive value of n indicates putting into operation, and a negative value of n indicates cutting off. Pick The domain of is [0, ];in, is the active damping limit value; According to M, N, and The domain of discourse is divided into M, N, and The K fuzzy subsets of M are obtained accordingly. , the fuzzy set of N is , The fuzzy set is ,in, , and Represents M, N, and The kth fuzzy subset of ; Step 3.2: Fuzzy reasoning: The operating conditions of large-scale off-grid solar hydrogen storage systems are divided into stable conditions and unstable conditions; Under stable conditions, when M<(m / 2) and N<0, the active damping weight factor is , in order to improve the dynamic response rate of the zth LCL type three-level grid-following inverter; Under unstable conditions, when M ≥ (m / 2) and N ≥ 0, the active damping weight factor is , in order to weaken the resonance peak of the zth LCL type three-level grid-following inverter; When M belongs to the rth fuzzy subset of its fuzzy set , and N belongs to the jth fuzzy subset in its fuzzy set When , the corresponding fuzzy output is recorded as , thus constructing fuzzy reasoning relationships, including: If r≥(K / 2) or j≥(K / 2), and r>j, Pick The K-r+1th fuzzy subset of the fuzzy set ; If r ≥ (K / 2) or j ≥ (K / 2), and when r < j, take the (K - j + 1)-th fuzzy subset in the fuzzy set of ; If r<(K / 2) and j<(K / 2), and r>j, Pick The K-r+1th fuzzy subset of the fuzzy set ; If r < (K / 2) and j < (K / 2), and when r < j, take the (K - j + 1)-th fuzzy subset in the fuzzy set of ; Step 3.3: Fuzzy output Defuzzification is performed to obtain the accurate active damping weight factor of the zth LCL three-level grid-following inverter. .

3. An electronic device, comprising a memory and a processor, characterized in that: The memory is used to store a program that supports the processor to execute the adaptive damping multi-machine resonance suppression method according to claim 1 or 2, and the processor is configured to execute the program stored in the memory.

4. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the adaptive damping multi-machine resonance suppression method according to claim 1 or 2 are executed.

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