Micro-grid VSG voltage control method and device with transient and steady state compensation

Abstract

The invention relates to a microgrid VSG voltage control method and device with transient steady state compensation, and the method and device are applied to a VSG voltage control model employing a reactive power-voltage regulation model. Compensating a reactive power-droop coefficient in the reactive power-voltage regulation model by adopting a transient compensation coefficient so as to suppress the change of the voltage; and in the microgrid on / off-grid process and when the transient process is finished, compensating a reactive-droop coefficient in the reactive-voltage regulation model by adopting a steady-state compensation coefficient so as to reduce the deviation degree of the voltage. According to the invention, voltage recovery can be accelerated.

Description

Technical Field

[0001] This invention relates to the field of microgrid voltage control, and in particular to a method and apparatus for controlling the voltage of a microgrid virtual synchronous generator (VSG) with metastable state compensation. Background Technology

[0002] During the VSG control process of microgrid connection / disconnection, VSG control needs to continuously respond to dynamic disturbances on the load side, such as the sudden connection of high-power loads and the emergency disconnection of important loads due to faults. If the load is large, it can easily cause severe voltage fluctuations. If it exceeds the system threshold, it may cause relay protection devices to malfunction.

[0003] In traditional microgrid parallel / off-grid VSG control, on the one hand, the voltage regulation lag leads to poor dynamic performance and an inability to react in a timely manner; on the other hand, when a short-circuit fault occurs in the system, the voltage support capability is insufficient and the short-circuit process regulation capability is poor. It can be seen that the existing VSG control strategy only considers the instantaneous voltage change process and ignores the transient steady-state process after the transient. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a microgrid VSG voltage control method and device with metastable state compensation, which can accelerate voltage recovery.

[0005] The technical solution adopted by this invention to solve its technical problem is: to provide a microgrid VSG voltage control method with metastable state compensation, applied to a VSG voltage control model using a reactive power-voltage regulation model, including the following methods:

[0006] At the moment of microgrid connection / disconnection, a transient compensation coefficient is used to compensate the reactive power-droop coefficient in the reactive power-voltage regulation model to suppress voltage changes;

[0007] During the microgrid connection / disconnection process and at the end of the transient process, a steady-state compensation coefficient is used to compensate the reactive power-droop coefficient in the reactive power-voltage regulation model to reduce the degree of voltage deviation.

[0008] The reactive power-voltage regulation model is expressed as follows: ,in, This is the virtual voltage amplitude. This is the system standard voltage. For integrator gain, This is the voltage-reactive droop factor. This is the inverter output voltage. Rated reactive power, The reactive power output by the system. For transformation operators.

[0009] The VSG voltage control model also includes an active power-frequency regulation model, which is expressed as follows: ,in, For virtual inertia, The angular velocity of the virtual rotor. The rate of change of the angular velocity of the virtual rotor. This is a reference value for active power. The active power output by the system. The damping coefficient is... Rated speed, This is the voltage phase angle.

[0010] The transient compensation coefficient is expressed as: ,in, For transient compensation coefficients, The change in voltage. The rate of change of voltage, For transient compensation parameters, For symbolic functions, it is represented as: , This is the trigger value for the first voltage change rate.

[0011] The steady-state compensation coefficient is expressed as: ,in, The steady-state compensation coefficient is... For steady-state compensation parameters, This is the inverter output voltage. and These are the upper and lower boundaries of the voltage trigger for steady-state compensation, respectively. The rate of change of voltage, This is the trigger value for the second voltage change rate.

[0012] The control logic for the reactive power-droop coefficient is expressed as follows: ,in, The dynamic reactive power droop factor is... This is the adjustment reference value for the reactive power droop coefficient. For transient compensation coefficients, This is the steady-state compensation coefficient.

[0013] The technical solution adopted by this invention to solve its technical problem is: to provide a microgrid VSG voltage control device with metastable state compensation, applied to a VSG voltage control model using a reactive power-voltage regulation model, comprising:

[0014] The transient compensation module is used to compensate the reactive power-droop coefficient in the reactive power-voltage regulation model at the moment of microgrid connection / disconnection to the grid in order to suppress voltage changes.

[0015] The steady-state compensation module is used to compensate the reactive power-droop coefficient in the reactive power-voltage regulation model by using a steady-state compensation coefficient during the microgrid connection / disconnection process and at the end of the transient process, so as to reduce the degree of voltage deviation.

[0016] The reactive power-voltage regulation model is expressed as follows: ,in, This is the virtual voltage amplitude. This is the system standard voltage. For integrator gain, This is the voltage-reactive droop factor. This is the inverter output voltage. Rated reactive power, The reactive power output by the system. For transformation operators.

[0017] The VSG voltage control model also includes an active power-frequency regulation model, which is expressed as follows: ,in, For virtual inertia, The angular velocity of the virtual rotor. The rate of change of the angular velocity of the virtual rotor. This is a reference value for active power. The active power output by the system. The damping coefficient is... Rated speed, This is the voltage phase angle.

[0018] The transient compensation coefficient is expressed as: ,in, For transient compensation coefficients, The change in voltage. The rate of change of voltage, For transient compensation parameters, For symbolic functions, it is represented as: , This is the trigger value for the first voltage change rate.

[0019] The steady-state compensation coefficient is expressed as: ,in, The steady-state compensation coefficient is... For steady-state compensation parameters, This is the inverter output voltage. and These are the upper and lower boundaries of the voltage trigger for steady-state compensation, respectively. The rate of change of voltage, This is the trigger value for the second voltage change rate.

[0020] The control logic for the reactive power-droop coefficient is expressed as follows: ,in, The dynamic reactive power droop factor is... This is the adjustment reference value for the reactive power droop coefficient. For transient compensation coefficients, This is the steady-state compensation coefficient.

[0021] The technical solution adopted by the present invention to solve its technical problem is: to provide an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the above-mentioned microgrid VSG voltage control method with metastable state compensation.

[0022] The technical solution adopted by the present invention to solve its technical problem is: to provide a computer-readable storage medium on which a computer program is stored, wherein when the computer program is executed by a processor, the steps of the above-mentioned microgrid VSG voltage control method with metastable state compensation are implemented.

[0023] Beneficial effects

[0024] Due to the adoption of the above technical solutions, this invention has the following advantages and positive effects compared with the prior art: This invention proposes that transient compensation coefficient and steady-state compensation coefficient respectively achieve voltage control for different stages of load disturbance in microgrid parallel / off-grid operation, solving the defect of traditional strategies that only focus on instantaneous voltage changes and ignore voltage deviations from the normal range. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the VSG voltage control model in the first embodiment of the present invention;

[0026] Figure 2 This is a flowchart of the microgrid VSG voltage control method with metastable state compensation according to the first embodiment of the present invention;

[0027] Figure 3 This is a schematic diagram of a grid-connected computing scenario in an embodiment of the present invention;

[0028] Figure 4 This is a schematic diagram of an off-grid computing scenario in an embodiment of the present invention;

[0029] Figure 5 This is a graph showing the voltage change rate under grid connection conditions in an embodiment of the present invention.

[0030] Figure 6 This is a graph showing the steady-state compensation coefficient variation under grid connection conditions in an embodiment of the present invention.

[0031] Figure 7This is a graph showing the change in transient compensation coefficient under grid connection conditions in an embodiment of the present invention.

[0032] Figure 8 This is a dynamic reactive power-droop coefficient variation curve for grid connection in an embodiment of the present invention;

[0033] Figure 9 This is a graph showing the change of the PCC point voltage over time in the grid-connected configuration of this invention.

[0034] Figure 10 This is a graph showing the rate of change of voltage under off-grid conditions in an embodiment of the present invention.

[0035] Figure 11 This is a graph showing the steady-state compensation coefficient variation in the off-grid situation according to an embodiment of the present invention.

[0036] Figure 12 This is a graph showing the change in transient compensation coefficient under off-grid conditions in an embodiment of the present invention.

[0037] Figure 13 This is a dynamic reactive power-droop coefficient variation curve for off-grid conditions in an embodiment of the present invention;

[0038] Figure 14 This is a graph showing the change of the PCC point voltage over time in an off-grid situation according to an embodiment of the present invention. Detailed Implementation

[0039] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0040] The first embodiment of the present invention relates to a microgrid VSG voltage control method with metastable state compensation, which can be applied to, for example... Figure 1 The VSG voltage control model shown.

[0041] The VSG voltage control model includes an active-frequency regulation model, a reactive-voltage regulation model, and a generator terminal reference voltage generation part.

[0042] The active power-frequency regulation model is expressed as follows:

[0043] (1)

[0044] This active-frequency regulation model is also called a virtual speed controller, in which... The angular velocity of the virtual rotor. The rate of change of the angular velocity of the virtual rotor. The active power output by the system. This is a reference value for active power. For virtual inertia, The damping coefficient is... This is the rated speed. This stage collects the active power output from the system. and the angular velocity of the virtual rotor The voltage phase angle is ultimately formed by using PI control. .

[0045] The reactive power-voltage regulation model is expressed as follows:

[0046] (2)

[0047] This reactive power-voltage regulation model is also called a virtual excitation speed controller, in which... This is the inverter output voltage. This is the system standard voltage. This is the voltage-reactive droop factor. The reactive power output by the system. Rated reactive power, For integrator gain, This is a transformation operator. This stage acquires the reactive power output of the system. and inverter output voltage The virtual voltage amplitude is ultimately formed by using PI control. .

[0048] The input to the terminal reference voltage generation section is the voltage phase angle. and virtual voltage amplitude The output terminal contains the three components of the reference voltage.

[0049] like Figure 2 As shown, the microgrid VSG voltage control method with metastable state compensation in this embodiment includes the following steps:

[0050] Step 1: At the instant of microgrid connection / disconnection, a transient compensation coefficient is used to compensate the reactive power-droop coefficient in the reactive power-voltage regulation model to suppress voltage changes.

[0051] According to the reactive power-voltage regulation model, we can obtain:

[0052] (3)

[0053] in, When a microgrid is operating in parallel or off-grid mode, if load switching causes voltage changes, it needs to be controlled. It cannot be too large, otherwise it will impact the system and damage the electrical components in the system. In this case, it can be controlled by the right-hand side of formula (3).

[0054] In microgrid parallel / off-grid scenarios, a sudden load connection can cause a momentary voltage drop, requiring the VSG to generate more reactive power. Suddenly decreases, while positive numbers It won't change immediately; at this point, if the voltage-reactive power droop factor... If it remains unchanged, then The voltage-reactive power droop factor increases significantly, at which point it is possible to design the voltage-reactive power droop factor. Increase to regulate the right side of equation (3) to suppress Changes are made to prevent voltage drops from occurring too quickly due to load fluctuations.

[0055] In microgrid parallel / off-grid scenarios, if a load suddenly disconnects from the grid, it will cause a momentary voltage rise. In this case, the VSG needs to absorb more reactive power. A sudden increase, while a negative number It won't change immediately; at this point, if the voltage-reactive power droop factor... If it remains unchanged, then The voltage-reactive power droop factor increases significantly, at which point it is possible to design the voltage-reactive power droop factor. Decrease to regulate the right side of equation (3) to suppress Changes are made to prevent voltage from rising too quickly due to load fluctuations.

[0056] Based on the above analysis, the transient compensation coefficient in this step can be:

[0057] (4)

[0058] in, For transient compensation coefficients, The change in voltage. The rate of change of voltage, For transient compensation parameters, For symbolic functions, it is represented as:

[0059] (5)

[0060] This is the first voltage change rate trigger value, i.e., the voltage change rate trigger value at which the transient compensation coefficient takes effect.

[0061] The transient compensation coefficient in this embodiment By dynamically adjusting the voltage change rate and sign function, the voltage value can be adjusted when the voltage changes instantaneously. When the load is suddenly connected to / disconnected from the grid, causing the voltage to drop / rise instantaneously, the reactive power-droop coefficient can be quickly increased / decreased through the transient compensation coefficient to suppress the voltage change rate and avoid impact on electrical components. At the same time, a first voltage change rate trigger value is set to prevent small fluctuations from causing false compensation.

[0062] Step 2: During the microgrid connection / disconnection process and at the end of the transient process, the reactive power-droop coefficient in the reactive power-voltage regulation model is compensated using a steady-state compensation coefficient to reduce the degree of voltage deviation.

[0063] When the fluctuations caused by microgrid load switching gradually disappear, that is, when the voltage change rate is less than a certain value (the transient process ends), it can be identified as a steady-state process. This steady-state process belongs to the period of continuous voltage drop / rise, as shown in equation (2). At this time, the voltage is basically unchanged. .

[0064] If this occurs after a voltage drop... If the value is greater than 0, the voltage-reactive power droop coefficient can be adjusted. To make the virtual voltage amplitude Increased voltage provides a supporting effect.

[0065] If this is after the voltage has risen... If the value is less than 0, the voltage-reactive power droop coefficient can be adjusted. To make the virtual voltage amplitude This reduces the voltage, thus suppressing it.

[0066] Based on the above analysis, the steady-state compensation coefficient in this step can be:

[0067] (6)

[0068] in, The steady-state compensation coefficient is... For steady-state compensation parameters, This is the inverter output voltage. and These are the upper and lower boundaries of the voltage trigger for steady-state compensation, respectively. This is the second voltage change rate trigger value, i.e., the voltage change rate trigger value at which the steady-state compensation coefficient takes effect.

[0069] Steady-state compensation coefficient in this embodiment After the load disturbance subsides (voltage change rate less than...), Voltage deviation is identified by voltage boundaries; if a voltage deviation is detected, the voltage-reactive power droop factor is increased. It supports and suppresses voltage changes, thereby enabling the microgrid to support / suppress voltage for a period of time after load switching under grid connection / disconnection conditions. It also prevents the steady-state compensation coefficient from being miscompensated during the steady-state process when the voltage is within the normal range by using the upper and lower voltage boundaries triggered by steady-state compensation.

[0070] In this embodiment, the voltage-reactive droop coefficient The control logic can be expressed as:

[0071] (7)

[0072] in, The dynamic reactive power droop factor is... This is the adjustment reference value for the reactive power-droop coefficient, which functions independently under normal conditions. The dynamic reactive power-droop coefficient... The upper and lower bounds are determined by the upper and lower bounds of the sum of the two compensation coefficients. This implementation constructs a dynamic adjustment model of a reference coefficient and dual compensation coefficients. Based on the reference coefficient, the voltage-reactive power droop coefficient is continuously output through the synergistic effect of the dual compensation coefficients, simplifying the traditional complex control algorithm. At the same time, it clearly states that the upper and lower bounds are determined by the sum of the two compensation coefficients, avoiding excessive deviation of the voltage-reactive power droop coefficient and ensuring control stability.

[0073] The present invention will be further illustrated by a specific embodiment below.

[0074] In this embodiment, the parameters of the microgrid are: DC side voltage. Grid-side line voltage Original active load Active load added and removed Power supply side filter inductor Power supply side filter resistor Power supply side filter capacitor Power supply side filter resistor Grid-side inductor Grid-side resistance The VSG voltage control model contains the virtual inertia of the power-frequency regulation model. Active power reference value Damping coefficient The system standard voltage in the reactive power-voltage regulation model Rated reactive power Integrator gain Transient compensation parameters Set as First voltage change rate trigger value Set as Steady-state compensation parameters Set as upper boundary of steady-state compensation trigger voltage Set as The lower boundary of the voltage triggered by steady-state compensation Set as The second voltage change rate trigger value is set to .

[0075] When the microgrid is in grid-connected state (see...) Figure 3 During operation, the active load at point PCC is increased from 150,000W to 300,000W in 0.3 seconds, and the active load of 150,000W is removed in 0.6 seconds. The voltage change at point PCC is measured. The simulation lasts for 0.9 seconds.

[0076] When the microgrid is off-grid (see...) Figure 4 During operation, the active load at point PCC is increased from 150,000W to 300,000W in 0.2 seconds, and the active load of 150,000W is removed in 0.4 seconds. The voltage change at point PCC is measured. The simulation lasts for 0.6 seconds.

[0077] Figures 5-9 The simulation of microgrid grid-connected operation is demonstrated. Figures 10-14 The simulation of off-grid operation of a microgrid is presented. The figures show that when the voltage suddenly drops / rises, the method of this embodiment can suppress the rate of voltage change; when the voltage recovers, it can accelerate the recovery to normal values; and when the voltage deviates from the normal range, if the voltage is too low, the method of this embodiment can support the grid voltage; if the voltage is too high, the method of this embodiment can suppress the grid voltage. Therefore, this embodiment proposes transient compensation coefficients and steady-state compensation coefficients to achieve voltage control at different stages of load disturbances during microgrid on-grid / off-grid operation, addressing the shortcomings of traditional strategies that only focus on instantaneous voltage changes and ignore voltage deviations from the normal range.

[0078] The second embodiment of the present invention relates to a microgrid VSG voltage control device with metastable state compensation, applied to a VSG voltage control model employing a reactive power-voltage regulation model, comprising:

[0079] The transient compensation module is used to compensate the reactive power-droop coefficient in the reactive power-voltage regulation model at the moment of microgrid connection / disconnection to the grid in order to suppress voltage changes.

[0080] The steady-state compensation module is used to compensate the reactive power-droop coefficient in the reactive power-voltage regulation model by using a steady-state compensation coefficient during the microgrid connection / disconnection process and at the end of the transient process, so as to reduce the degree of voltage deviation.

[0081] The reactive power-voltage regulation model is expressed as follows: ,in, This is the virtual voltage amplitude. This is the system standard voltage. For integrator gain, This is the voltage-reactive droop factor. This is the inverter output voltage. Rated reactive power, The reactive power output by the system. For transformation operators.

[0082] The VSG voltage control model also includes an active power-frequency regulation model, which is expressed as follows: ,in, For virtual inertia, The angular velocity of the virtual rotor. The rate of change of the angular velocity of the virtual rotor. This is a reference value for active power. The active power output by the system. The damping coefficient is... Rated speed, This is the voltage phase angle.

[0083] The transient compensation coefficient is expressed as: ,in, For transient compensation coefficients, The change in voltage. The rate of change of voltage, For transient compensation parameters, For symbolic functions, it is represented as: , This is the trigger value for the first voltage change rate.

[0084] The steady-state compensation coefficient is expressed as: ,in, The steady-state compensation coefficient is... For steady-state compensation parameters, This is the inverter output voltage. and These are the upper and lower boundaries of the voltage trigger for steady-state compensation, respectively. The rate of change of voltage, This is the trigger value for the second voltage change rate.

[0085] The control logic for the reactive power-droop coefficient is expressed as follows: ,in, The dynamic reactive power droop factor is... This is the adjustment reference value for the reactive power droop coefficient. For transient compensation coefficients, This is the steady-state compensation coefficient.

[0086] The third embodiment of the present invention relates to an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the microgrid VSG voltage control method with metastable state compensation of the first embodiment.

[0087] The fourth embodiment of the present invention relates to a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the microgrid VSG voltage control method with metastable state compensation of the first embodiment.

[0088] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product implemented on one or more computer-usable storage media (including, but not limited to, disk storage and optical storage) containing computer-usable program code.

[0089] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0090] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to operate in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction methods implemented in a process. Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0091] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0092] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A microgrid VSG voltage control method with transient state compensation, characterized in that, Applied to VSG voltage control models employing reactive power-voltage regulation models, the following methods are included: At the moment of microgrid connection / disconnection, a transient compensation coefficient is used to compensate the reactive power-droop coefficient in the reactive power-voltage regulation model to suppress voltage changes; During the microgrid connection / disconnection process and at the end of the transient process, a steady-state compensation coefficient is used to compensate the reactive power-droop coefficient in the reactive power-voltage regulation model to reduce the degree of voltage deviation.

2. The microgrid VSG voltage control method with transient state compensation according to claim 1, characterized in that, The reactive power-voltage regulation model is expressed as follows: ,in, This is the virtual voltage amplitude. This is the system standard voltage. For integrator gain, This is the voltage-reactive droop factor. This is the inverter output voltage. Rated reactive power, The reactive power output of the system. For transformation operators.

3. The microgrid VSG voltage control method with transient state compensation according to claim 1, characterized in that, The VSG voltage control model also includes an active power-frequency regulation model, which is expressed as follows: ,in, For virtual inertia, The angular velocity of the virtual rotor. The rate of change of the angular velocity of the virtual rotor. This is a reference value for active power. The active power output by the system. The damping coefficient is... Rated speed, This is the voltage phase angle.

4. The microgrid VSG voltage control method with transient state compensation according to claim 1, characterized in that, The transient compensation coefficient is expressed as: ,in, For transient compensation coefficients, The change in voltage. The rate of change of voltage, For transient compensation parameters, For symbolic functions, it is represented as: , This is the trigger value for the first voltage change rate.

5. The microgrid VSG voltage control method with metastable state compensation according to claim 1, characterized in that, The steady-state compensation coefficient is expressed as: ,in, The steady-state compensation coefficient is... For steady-state compensation parameters, This is the inverter output voltage. and These are the upper and lower boundaries of the voltage trigger for steady-state compensation, respectively. The rate of change of voltage, This is the trigger value for the second voltage change rate.

6. The microgrid VSG voltage control method with transient state compensation according to claim 1, characterized in that, The control logic for the reactive power-droop coefficient is expressed as follows: ,in, The dynamic reactive power droop factor is... This is the adjustment reference value for the reactive power droop coefficient. For transient compensation coefficients, This is the steady-state compensation coefficient.

7. A microgrid VSG voltage control device with transient state compensation, characterized in that, VSG voltage control models applied to reactive power-voltage regulation models include: The transient compensation module is used to compensate the reactive power-droop coefficient in the reactive power-voltage regulation model at the moment of microgrid connection / disconnection to the grid in order to suppress voltage changes. The steady-state compensation module is used to compensate the reactive power-droop coefficient in the reactive power-voltage regulation model by using a steady-state compensation coefficient during the microgrid connection / disconnection process and at the end of the transient process, so as to reduce the degree of voltage deviation.

8. The microgrid VSG voltage control apparatus according to claim 7, characterized in that, The reactive power-voltage regulation model is expressed as follows: ,in, This is the virtual voltage amplitude. This is the system standard voltage. For integrator gain, This is the voltage-reactive droop factor. This is the inverter output voltage. Rated reactive power, The reactive power output of the system. For transformation operators.

9. The microgrid VSG voltage control apparatus according to claim 7, wherein, The VSG voltage control model also includes an active power-frequency regulation model, which is expressed as follows: ,in, For virtual inertia, The angular velocity of the virtual rotor. The rate of change of the angular velocity of the virtual rotor. This is a reference value for active power. The active power output by the system. The damping coefficient is... For the rated speed, This is the voltage phase angle.

10. The microgrid VSG voltage control apparatus according to claim 7, wherein, The transient compensation coefficient is expressed as: ,in, For transient compensation coefficients, The change in voltage. The rate of change of voltage, For transient compensation parameters, For symbolic functions, it is represented as: , This is the trigger value for the first voltage change rate.

11. The microgrid VSG voltage control apparatus according to claim 7, wherein, The steady-state compensation coefficient is expressed as: ,in, The steady-state compensation coefficient is... For steady-state compensation parameters, This is the inverter output voltage. and These are the upper and lower boundaries of the voltage trigger for steady-state compensation, respectively. The rate of change of voltage, This is the trigger value for the second voltage change rate.

12. The microgrid VSG voltage control apparatus according to claim 7, wherein, The control logic of the reactive-droop coefficient is represented as: wherein, is the dynamic reactive-droop coefficient, is the adjustment reference value of the reactive-droop coefficient, is the transient compensation coefficient, is the steady-state compensation coefficient.

13. An electronic device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the microgrid VSG voltage control method with metastable state compensation as described in any one of claims 1-6.

14. A computer-readable storage medium having stored thereon a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the microgrid VSG voltage control method with metastable state compensation as described in any one of claims 1-6.

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