Microgrid power quality optimization control method and device based on event triggering mechanism

Abstract

The present invention discloses a microgrid power quality optimization control method and device based on an event-triggered mechanism, comprising the following steps: 1. generating a sinusoidal voltage using droop control and solving the bus voltage using virtual impedance control; 2. extracting the harmonic currents of the distribution network and constructing a virtual impedance expression; 3. constructing a time-triggered leader-follower distributed controller based on the extracted harmonic currents of the distribution network and the communication network of the microgrid; and 4. determining the triggering conditions of the leader-follower distributed controller. When the triggering conditions are met, the leader-follower distributed control is triggered to generate a virtual impedance. Simultaneously, distributed collaborative control of each inverter is performed based on harmonic power sharing. The present invention can control the inverters to absorb different harmonic powers, thereby improving the power quality of the microgrid.

Description

Technical Field

[0001] The present invention relates to the field of microgrid control technology, and in particular to a microgrid power quality optimization control method and device based on an event triggering mechanism. Background Art

[0002] With the influx of asymmetric and nonlinear loads in distribution networks, power quality issues are becoming increasingly prominent. In microgrid operation, improper distribution of reactive power and harmonic power among inverters can severely impact the system's efficient and stable operation. Coordinated control of multiple inverters is crucial for reliable microgrid operation. This requires inverters to properly distribute load power based on their rated power to avoid overload conditions.

[0003] Existing technologies primarily focus on achieving precise power distribution among inverters, but neglect the utilization of excess inverter capacity, failing to leverage this resource to improve microgrid power quality. While preventing inverter overload, the key challenge is how to maximize harmonic power absorption while reducing the communication burden and data transmission volume of the entire control system. Summary of the Invention

[0004] The purpose of the present invention is to overcome the defects in the prior art that a large number of asymmetric loads are connected to the distribution network, resulting in a decrease in the power quality of the distribution network, a heavy communication burden on the inverter when performing control, and an impact on the overall operating efficiency of the distribution network. A method and device for optimizing the power quality of a microgrid based on an event triggering mechanism are provided.

[0005] The purpose of the present invention is achieved through the following technical solutions:

[0006] The microgrid power quality optimization control method based on the event trigger mechanism includes the following steps:

[0007] Step 1: Use droop control to generate sinusoidal voltage and use virtual impedance control to solve the bus voltage;

[0008] Step 2: extract the harmonic current of the distribution network and construct a virtual impedance expression based on the relationship between the bus voltage and the harmonic current;

[0009] Step 3: Based on the fundamental component of the sinusoidal voltage, the extracted harmonic current of the distribution network, and the communication network of the microgrid, an event-triggered leader-follower distributed controller is constructed, and the output of the virtual impedance expression is used as the state variable input;

[0010] Step 4: Determine the triggering conditions of the leader-follower distributed controller. When the triggering conditions are met, the leader-follower distributed control is triggered to generate virtual impedance. At the same time, each inverter is controlled based on harmonic power sharing to perform distributed collaborative control.

[0011] In step 1 of this solution, the method serves as the logical starting point. It establishes the microgrid's basic voltage generation mechanism through droop control and virtual impedance control, providing the necessary prerequisites for subsequent harmonic processing, controller design, and coordinated control. Step 2, through mathematical modeling, converts harmonic currents into virtual impedance expressions, providing executable control parameters for the distributed control in steps 3-4, forming a "problem modeling-control execution" technical chain. This design utilizes an event-triggered leader-follower microgrid harmonic sharing control strategy, taking into account both harmonic sharing and bus voltage management. The event-triggered mechanism effectively reduces the communication burden between inverters, avoids unnecessary data transfer, and maximizes the microgrid's power quality. By setting the value of the virtual leader node, the amount of harmonic power absorbed by the inverter can be controlled, thereby improving power quality, making it suitable for practical microgrid requirements.

[0012] Preferably, in step 1, droop control is used to generate a sinusoidal voltage, specifically:

[0013] Detect the actual output active power and reactive power of the inverter as the input signal for droop control;

[0014] Multiply the deviation of the actual output active power and reactive power from the rated power by the corresponding droop coefficient to obtain the frequency deviation and voltage amplitude deviation;

[0015] The frequency deviation and voltage amplitude deviation are respectively superimposed on the rated value to obtain the actual frequency and voltage amplitude;

[0016] Generates a sinusoidal voltage signal with actual frequency and voltage amplitude.

[0017] Preferably, in step 2, the method for extracting harmonic currents of the distribution network is to separate and extract harmonic currents of different sub-orders by using a method based on cross-cancellation feedback of a second-order generalized integral orthogonal signal generator.

[0018] Preferably, in step 2, the process of constructing the virtual impedance expression is:

[0019] After completing the separation and extraction of different subharmonic currents, the distributed power inverter output harmonic voltage reference signal is obtained by multiplying the harmonic current by an impedance coefficient, and then the virtual impedance of the distributed power inverter at the harmonic frequency is obtained.

[0020] Preferably, the step 3 is specifically as follows:

[0021] A state-space model of system harmonic power is constructed, each inverter is considered as an agent, and the error between the agent and the virtual leader node is defined. When a spanning tree exists in the communication network, the agent state can converge to the leader node.

[0022] Introducing an event trigger mechanism, setting the time-varying error of each agent, and updating the agent's control input when the trigger condition is met to avoid continuous communication;

[0023] Design a control protocol to integrate the latest trigger status of itself and its neighbors for coordinated updates.

[0024] Preferably, in the design control protocol, in the process of integrating the latest trigger status of itself and its neighbors for collaborative updating, a consensus variable is introduced to integrate the harmonic power and the remaining capacity into a single variable. When the remaining capacity of the inverter decreases, the consensus variable automatically increases, triggering the control system to reduce the harmonic absorption and prevent overload.

[0025] Preferably, in step 3, the Lyapunov method is also used to prove the stability of the leader-follower distributed controller control strategy.

[0026] Preferably, in step 4, the triggering condition of the leader-follower distributed controller is determined by the stability analysis results and execution conditions. When the stability value reaches the trigger threshold, the controller samples and outputs, thereby updating the value stored in the controller triggered by the last event.

[0027] The microgrid power quality optimization control device based on event triggering mechanism includes:

[0028] Voltage generation and solution module, used to generate sinusoidal voltage using droop control and solve bus voltage using virtual impedance control;

[0029] Harmonic current processing module, used to extract the harmonic current of the distribution network and construct a virtual impedance expression;

[0030] A controller building module is used to build an event-triggered leader-follower distributed controller based on the extracted harmonic current of the distribution network and the communication network of the microgrid;

[0031] The trigger and control module is used to determine the trigger conditions of the leader-follower distributed controller. When the trigger conditions are met, the leader-follower distributed control is triggered to generate virtual impedance. At the same time, the inverters are controlled based on harmonic power sharing for distributed collaborative control.

[0032] Preferably, the trigger and control module includes:

[0033] Stability analysis unit, used to prove the stability of the control strategy using the Lyapunov method and determine the relationship between the trigger threshold and the system parameters;

[0034] The threshold dynamic adjustment unit is used to adjust the trigger threshold in real time according to the frequency fluctuation and voltage deviation of the microgrid, balancing the control accuracy and communication overhead.

[0035] The beneficial effect of the present invention is that the event trigger control of the present invention will only transmit data when the trigger condition is met, that is, a certain threshold is reached, which effectively avoids useless data flow and reduces a lot of unnecessary calculations for the entire optimization management method.

[0036] The control variable in the adopted consistency control strategy introduces the remaining capacity. By setting the value of the virtual leader node, the inverter can be effectively avoided from being overloaded, thereby also being able to well protect the inverter.

[0037] Because the virtual leader node is a virtual value in the control framework and can be flexibly adjusted, by adjusting the values ​​of different virtual leader nodes, the inverter can be controlled to absorb different harmonic powers and improve the power quality of the microgrid. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 is a flow chart of the present invention;

[0039] Figure 2 is the block diagram of the power droop controller;

[0040] Figure 3 This is the schematic diagram of the inverter virtual impedance control;

[0041] Figure 4 This is a schematic diagram of the harmonic current extraction method based on SOGI-QSG cross cancellation;

[0042] Figure 5 Microgrid simulation schematic;

[0043] Figure 6 It is a schematic diagram of the ratio of harmonic power to residual capacity of each inverter;

[0044] Figure 7 It is a schematic diagram of the triggering moment of the controller;

[0045] Figure 8 It is a schematic diagram of the bus voltage distortion rate before and after control is applied. DETAILED DESCRIPTION

[0046] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this application will be thorough and complete and will fully convey the concepts of the example embodiments to those skilled in the art.

[0047] In addition, described feature, structure or characteristic can be combined in one or more embodiments in any suitable manner.In the following description, many specific details are provided so as to provide a full understanding of the embodiments of the present application. However, it will be appreciated by those skilled in the art that the technical scheme of the present application can be put into practice without one or more of the specific details, or other methods, components, devices, steps etc. can be adopted. In other cases, known methods, devices, implementations or operations are not shown or described in detail to avoid blurring the various aspects of the application.

[0048] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically separate entities. That is, these functional entities may be implemented in software, in one or more hardware modules or integrated circuits, or in different networks and / or processor devices and / or microcontroller devices.

[0049] The flowcharts shown in the accompanying drawings are for illustrative purposes only and do not necessarily include all contents and operations / steps, nor must they be executed in the order described. For example, some operations / steps may be decomposed, while others may be combined or partially combined. Therefore, the actual execution order may vary depending on the actual situation.

[0050] Example: Microgrid power quality optimization control method based on event triggering mechanism, such as Figure 1 As shown, the following steps are included:

[0051] Step 1: Use droop control to generate sinusoidal voltage and use virtual impedance control to solve the bus voltage;

[0052] Step 2: extract the harmonic current of the distribution network and construct a virtual impedance expression based on the relationship between the bus voltage and the harmonic current;

[0053] Step 3: Based on the fundamental component of the sinusoidal voltage, the extracted harmonic current of the distribution network, and the communication network of the microgrid, an event-triggered leader-follower distributed controller is constructed, and the output of the virtual impedance expression is used as the state variable input;

[0054] Step 4: Determine the triggering conditions of the leader-follower distributed controller. When the triggering conditions are met, the leader-follower distributed control is triggered to generate virtual impedance. At the same time, each inverter is controlled based on harmonic power sharing to perform distributed collaborative control.

[0055] This design utilizes an event-triggered leader-follower microgrid harmonic sharing control strategy, taking into account both harmonic sharing and bus voltage management. This event-triggered mechanism effectively reduces the communication burden between inverters, avoids unnecessary data transfer, and maximizes microgrid power quality. By setting the value of the virtual leader node, the amount of harmonic power absorbed by the inverter can be controlled, thereby improving power quality and meeting the needs of actual microgrids.

[0056] In step 1, droop control is used to generate a sinusoidal voltage, specifically:

[0057] Detect the actual output active power and reactive power of the inverter as the input signal for droop control;

[0058] Multiply the deviation of the actual output active power and reactive power from the rated power by the corresponding droop coefficient to obtain the frequency deviation and voltage amplitude deviation;

[0059] The frequency deviation and voltage amplitude deviation are respectively superimposed on the rated value to obtain the actual frequency and voltage amplitude;

[0060] Generates a sinusoidal voltage signal with actual frequency and voltage amplitude.

[0061] Specifically, because the inverter output voltage phase angle is difficult to control directly, frequency regulation is often used instead in practical applications. Droop control is a power feedback regulation mechanism that leverages these characteristics. It reduces the inverter's output voltage frequency as its active power output increases, and reduces its voltage amplitude as its reactive power output increases, thereby automatically distributing load power among distributed power sources in a microgrid. The traditional control equations for active power-frequency droop and reactive power-voltage droop are shown below.

[0062] (1.1)

[0063] In the above formula, f n and U n are the inverter output voltage u o Rated frequency and amplitude, f i and U i The output voltage u o The actual frequency and amplitude of P n and Q n is the rated active and reactive power of the distributed power inverter, P i and Q i is the actual output active and reactive power, m i and n i are the active and reactive droop coefficients respectively. Based on formula (1.1), the complete process of the droop control link can be obtained as follows: Figure 2 shown.

[0064] The virtual impedance control principle of the inverter is as follows Figure 3 As shown in the figure, G V (s) is the transfer function of the voltage loop, and its expression is:

[0065] (1.2)

[0066] Where k U is the voltage loop proportional coefficient, k r1 are the resonance coefficients, ω1 and ω c are the resonant frequency and cutoff frequency of the quasi-PR controller, and s is the Laplace operator, which is a complex variable used in frequency domain analysis.

[0067] G I (s) includes the proportional coefficient k of the inductor current loop I , the equivalent gain k of the inverter pwm And the transfer function of the delay link, G I The expression of (s) is as follows:

[0068] (1.3)

[0069] Where k I is the current loop proportional coefficient, k pwm is the inverter equivalent gain, T s To control the frequency,

[0070] Combining the above formula, we can get the expression of the inverter output voltage:

[0071] (1.4)

[0072] Where u o (s) is the Laplace transform of the inverter output voltage, G(s) is the system open-loop transfer function, u ref (s) is the Laplace transform of the reference voltage, Z eq (s) is the equivalent impedance, including the inherent characteristics of the inverter and the virtual impedance, i o (s) is the Laplace transform of the inverter output current, L f is the filter inductor, C f is the filter capacitor, R f is the filter resistor, Z o (s) is the inherent output impedance of the inverter, Z v (s) is the virtual impedance, G vir (s) is the transfer function related to the virtual impedance.

[0073] In the step 2, the method for extracting the harmonic current of the distribution network is to separate and extract the harmonic currents of different orders by using a method based on the cross-cancellation feedback of a second-order generalized integral orthogonal signal generator.

[0074] Specifically, such as Figure 4 As shown, the transfer function expression of the SOGI-QSG module is as follows:

[0075] (1.5)

[0076] Where, ω h is the resonant frequency, k h Used to determine the bandwidth of SOGI-QSG. hα (s) is the coupling coefficient of the hth harmonic on the α axis, G hβ (s) is the coupling coefficient of the hth harmonic on the β axis, G hα (s) and G hβ (s) in ω h The amplitude gain at is 1, but the phases are 0° and 90°, respectively. After cross-cancellation feedback, the transfer function of current separation extraction at different frequencies can be calculated using the following equation.

[0077] (1.6)

[0078] (1.7)

[0079] In the above formula, T nα (s) is the transfer function of the hth harmonic on the α axis, T hβ (s) is the transfer function of the hth harmonic on the β axis, T nα (s) and T hβ (s) is also in ω h The amplitude gain at is 1, and the phase difference is 90°. To sum up the harmonic transfer functions on the α axis except the hth order.

[0080] In step 2, the process of constructing the virtual impedance expression is:

[0081] After completing the separation and extraction of different harmonic currents, the harmonic voltage reference signal output by the distributed power inverter is obtained by multiplying the harmonic current by an impedance coefficient, and then the virtual impedance of the distributed power inverter at the harmonic frequency is obtained. As shown:

[0082] (1.8)

[0083] Among them, R vh With L vhare the virtual harmonic resistance and inductance values ​​to be designed respectively.

[0084] The step 3 is specifically as follows:

[0085] A state-space model of system harmonic power is constructed, each inverter is considered as an agent, and the error between the agent and the virtual leader node is defined. When a spanning tree exists in the communication network, the agent state can converge to the leader node.

[0086] Introducing an event trigger mechanism, setting the time-varying error of each agent, and updating the agent's control input when the trigger condition is met to avoid continuous communication;

[0087] Design a control protocol to integrate the latest trigger status of itself and its neighbors for coordinated updates.

[0088] In the design control protocol described above, a consensus variable is introduced to integrate the latest trigger status of itself and its neighbors for collaborative update, and the harmonic power and remaining capacity are integrated into a single variable. When the remaining capacity of the inverter decreases, the consensus variable automatically increases, triggering the control system to reduce the harmonic absorption and prevent overload.

[0089] Specifically, the state space model of system harmonic power can be constructed as:

[0090] (1.9)

[0091] u i is the control input for each agent. The error between each agent and the leader node is defined as

[0092] (1.10)

[0093] Where w i (t) is a quantity that changes with time t, x i (t) represents the state variable of the i-th object at time t, and x0 is a reference benchmark value.

[0094] When a spanning tree exists, the decision value of each agent will converge to the value of the leader node.

[0095] In leader-follower distributed control, each agent uses information from neighboring agents to determine the time of its own event triggering and then updates its own control input. For each agent i, a time-varying error is introduced. and The sequence of events triggering execution is t 0i ,t 1i ..., corresponding to a control sequence u(t0),u(t1), between control updates, the value of the input u remains unchanged in a zero-order hold manner and is equal to the previous control update, that is,

[0096] (1.11)

[0097] Where u(t) is a function of time t, u(t i ) is the function u(t) at t i The value of the moment.

[0098] According to this method, the time-varying error is defined as follows:

[0099] (1.12)

[0100] Where, α i (t) represents the state variable x i (t) and the starting point of the interval Time x i The difference in values, β i (t) represents the state variable w i (t) and the starting point of the interval Time w i The difference in values, It represents the time when the i-th agent triggers the k-th time,

[0101] The control protocol of this article is as follows:

[0102] (1.13)

[0103] in , , , so for every , is the time of the last event trigger for agent j. For each agent j, the last event trigger time is recorded. Therefore, each agent incorporates the latest trigger state value of each neighboring node into its control law. The control strategy of agent i has a dual update mechanism: one based on its own event trigger time, and the other based on the event response time of the synchronously triggered neighboring nodes, thus achieving coordinated updates of local control parameters.

[0104] In order to avoid the situation of variable surge, the remaining capacity is directly reflected in the consensus variable of the controller. The present invention designs a new consensus variable, as shown in the following formula:

[0105] (1.14)

[0106] Where, represents the amount of harmonic correlation between the i-th object at time t, represents the remaining amount of the i-th object at time t, It represents the ratio of the harmonic correlation of the i-th object at time t to the total correlation (harmonic + residual) through the ratio of the two.

[0107] At the same time, the value of the virtual leader node is also The formula is consistent with that of , and we can make the inverter absorb more harmonic power by setting different values. The virtual leader node used in the present invention is a numerical value and does not need to be transmitted through an actual line.

[0108] The additional virtual impedance can be expressed as:

[0109] (1.15)

[0110] Where, Indicates the virtual inductance value of the hth harmonic, Indicates the virtual resistance value of the hth harmonic, and Represents the gain factor of the inductor and resistor.

[0111] In step 3, the Lyapunov method is also used to prove the stability of the leader-follower distributed controller control strategy.

[0112] In step 4, the triggering condition of the leader-follower distributed controller is determined by the stability analysis results and execution conditions. When the stability value reaches the trigger threshold, the controller samples and outputs, thereby updating the value stored in the controller triggered by the last event.

[0113] The microgrid power quality optimization control device based on event triggering mechanism includes:

[0114] Voltage generation and solution module, used to generate sinusoidal voltage using droop control and solve bus voltage using virtual impedance control;

[0115] Harmonic current processing module, used to extract the harmonic current of the distribution network and construct a virtual impedance expression;

[0116] A controller building module is used to build an event-triggered leader-follower distributed controller based on the extracted harmonic current of the distribution network and the communication network of the microgrid;

[0117] The trigger and control module is used to determine the trigger conditions of the leader-follower distributed controller. When the trigger conditions are met, the leader-follower distributed control is triggered to generate virtual impedance. At the same time, the inverters are controlled based on harmonic power sharing for distributed collaborative control.

[0118] The trigger and control module includes:

[0119] Stability analysis unit, used to prove the stability of the control strategy using the Lyapunov method and determine the relationship between the trigger threshold and the system parameters;

[0120] The threshold dynamic adjustment unit is used to adjust the trigger threshold in real time according to the frequency fluctuation and voltage deviation of the microgrid, balancing the control accuracy and communication overhead.

[0121] In order to verify the effectiveness of the proposed adaptive virtual impedance control strategy in the microgrid system, a multi-bus distribution network simulation model is built in Matlab / Simulink, as shown in Figure 5 shown.

[0122] The simulation parameters are shown in Table 1:

[0123] Table 1 Simulation parameters of each component of the microgrid

[0124] ;

[0125] Figure 6 The figure shows the ratio of harmonic power to remaining capacity of each inverter. When control is put into operation at 2s, it can be observed that the remaining capacity and harmonic power of the three inverters finally reach the set leading value, which effectively avoids inverter overload.

[0126] Figure 7 This represents the inverter trigger sequence after control is applied. A median value of 1 indicates that the event triggering the controller has reached the threshold, meeting the trigger condition, and performing data collection and transmission, thereby applying virtual impedance. A value of 0 indicates that the controller has not triggered and does not transmit data. Table 2 shows the triggering percentage of each inverter under this control method compared to traditional control. It can be observed that compared to traditional methods, this control method can save approximately 99% of data transmission, indicating that it can significantly reduce the communication burden and effectively avoid ineffective data transmission.

[0127] Table 2 Triggering time ratio of each inverter

[0128] ;

[0129] Depend on Figure 8 It can be seen that the bus voltage distortion rate is about 7.8% before the control is applied, and the voltage distortion rate is about 4.3% after the control is applied, which greatly improves the power quality of the microgrid. This shows that this method can be effectively applied to actual microgrids and can effectively improve the power quality of the microgrid while preventing inverter overload.

[0130] Those skilled in the art will readily conceive of other embodiments of the present application after considering the specification and practicing the embodiments disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present application that follow the general principles of this application and include common knowledge or customary techniques in the art that are not disclosed herein.

[0131] It should be understood that the present application is not limited to the exact structure described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A microgrid power quality optimization control method based on an event trigger mechanism is characterized by: The following steps are involved: Step 1: Use droop control to generate sinusoidal voltage and use virtual impedance control to solve the bus voltage; Step 2: extract the harmonic current of the distribution network and construct a virtual impedance expression based on the relationship between the bus voltage and the harmonic current; Step 3: Based on the fundamental component of the sinusoidal voltage, the extracted harmonic current of the distribution network, and the communication network of the microgrid, an event-triggered leader-follower distributed controller is constructed, and the output of the virtual impedance expression is used as the state variable input; Step 4: Determine the triggering conditions of the leader-follower distributed controller. When the triggering conditions are met, the leader-follower distributed control is triggered, generating virtual impedance and simultaneously controlling each inverter based on harmonic power sharing for distributed collaborative control. In step 2, the method for extracting harmonic currents of the distribution network is to separate and extract harmonic currents of different sub-orders by using a method based on cross-cancellation feedback of a second-order generalized integral orthogonal signal generator; In step 2, the process of constructing the virtual impedance expression is: After completing the separation and extraction of different subharmonic currents, the harmonic voltage reference signal output by the distributed power inverter is obtained by multiplying the harmonic current by an impedance coefficient, and then the virtual impedance of the distributed power inverter at the harmonic frequency is obtained; The step 3 is specifically as follows: A state-space model of system harmonic power is constructed, each inverter is considered as an agent, and the error between the agent and the virtual leader node is defined. When a spanning tree exists in the communication network, the agent state can converge to the leader node. Introducing an event trigger mechanism, setting the time-varying error of each agent, and updating the agent's control input when the trigger condition is met to avoid continuous communication; Design a control protocol to integrate the latest trigger status of itself and its neighbors for coordinated updates; In step 2, the process of constructing the virtual impedance expression is: After completing the separation and extraction of different harmonic currents, the harmonic voltage reference signal output by the distributed power inverter is obtained by multiplying the harmonic current by an impedance coefficient, and then the virtual impedance of the distributed power inverter at the harmonic frequency is obtained, as shown in the following formula: ； in, R vh and L vh are the virtual harmonic resistance and inductance values ​​to be designed, for h Subharmonics in α The transfer function on the axis, ω h is the resonant frequency, for h Subharmonics in β The transfer function on the axis, G ( s ) is the open-loop transfer function of the system.

2. The microgrid power quality optimization control method based on event triggering mechanism according to claim 1 is characterized in that: In step 1, droop control is used to generate a sinusoidal voltage, specifically: Detect the actual output active power and reactive power of the inverter as the input signal for droop control; Multiply the deviation of the actual output active power and reactive power from the rated power by the corresponding droop coefficient to obtain the frequency deviation and voltage amplitude deviation; The frequency deviation and voltage amplitude deviation are respectively superimposed on the rated value to obtain the actual frequency and voltage amplitude; Generates a sinusoidal voltage signal with actual frequency and voltage amplitude.

3. The microgrid power quality optimization control method based on event triggering mechanism according to claim 1 is characterized in that: In the design control protocol described above, a consensus variable is introduced to integrate the latest trigger status of itself and its neighbors for collaborative update, and the harmonic power and remaining capacity are integrated into a single variable. When the remaining capacity of the inverter decreases, the consensus variable automatically increases, triggering the control system to reduce the harmonic absorption and prevent overload.

4. The microgrid power quality optimization control method based on event triggering mechanism according to claim 1 is characterized in that: In step 3, the Lyapunov method is also used to prove the stability of the leader-follower distributed controller control strategy.

5. The microgrid power quality optimization control method based on event triggering mechanism according to claim 3 is characterized in that: In step 4, the triggering condition of the leader-follower distributed controller is determined by the stability analysis results and execution conditions. When the stability value reaches the trigger threshold, the controller samples and outputs, thereby updating the value stored in the controller triggered by the last event.

6. A microgrid power quality optimization control device based on an event trigger mechanism, used to implement the microgrid power quality optimization control method based on an event trigger mechanism as described in any one of claims 1 to 5, characterized in that: include: Voltage generation and solution module, used to generate sinusoidal voltage using droop control and solve bus voltage using virtual impedance control; Harmonic current processing module, used to extract the harmonic current of the distribution network and construct a virtual impedance expression; A controller building module is used to build an event-triggered leader-follower distributed controller based on the extracted harmonic current of the distribution network and the communication network of the microgrid; The trigger and control module is used to determine the trigger conditions of the leader-follower distributed controller. When the trigger conditions are met, the leader-follower distributed control is triggered to generate virtual impedance. At the same time, the inverters are controlled based on harmonic power sharing for distributed collaborative control.

7. The microgrid power quality optimization control device based on event triggering mechanism according to claim 6 is characterized in that: The trigger and control module includes: Stability analysis unit, used to prove the stability of the control strategy using the Lyapunov method and determine the relationship between the trigger threshold and the system parameters; The threshold dynamic adjustment unit is used to adjust the trigger threshold in real time according to the frequency fluctuation and voltage deviation of the microgrid, balancing the control accuracy and communication overhead.

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