Adaptive regulation control method for virtual synchronous generator

Abstract

The adaptive adjustment control method of virtual synchronous generator solves the problem of how to prevent the overcharging and over-discharging of the DC bus capacitor and the system instability caused by excessive voltage fluctuation, and belongs to the technical field of virtual synchronous generator control. The present application comprises: obtaining the output power response signal curve of the VSG inverter according to the three-phase voltage and current of the load end of the light storage grid-connected system, and then obtaining the system angular frequency change rate and angular frequency change amount Δω through the VSG active-frequency loop with the power reference value; according to Δω and the voltage fluctuation value signal ΔV of the DC side bus capacitor dc , dynamically adjusting the virtual rotational inertia coefficient J of the VSG active-frequency loop, generating the actual angular frequency ω of the VSG inverter m , combining with the reference voltage phase signal θ, and combining the electromotive force E generated by the virtual synchronous generator to synthesize the voltage reference value U ref ; inputting U ref into the control module of the light storage grid-connected system to generate the PWM signal for controlling the VSG inverter.

Description

TECHNICAL FIELD

[0001] The application relates to an adaptive regulation control method of a virtual synchronous generator considering DC bus capacitor voltage stability, and belongs to the technical field of virtual synchronous generator control. BACKGROUND

[0002] The popularization of new energy power generation makes high-proportion new energy power grids a feature of new-generation power systems, but large-scale grid connection of photovoltaic systems poses challenges to the dynamic response and stability of power grids. Photovoltaic grid-connected inverters are prone to triggering output frequency dynamic adjustment due to the intermittency, randomness and volatility of photovoltaic power generation and slight disturbances of power grids, which may lead to power fluctuation impact and even affect the safety of power grids in extreme cases. At the same time, large-scale access of new energy power generation equipment will weaken the rotational inertia and damping of power grids and reduce the resistance to recovery. At present, photovoltaic storage inverters mostly adopt grid-following control strategies and rely on other devices to provide voltage sources to maintain voltage stability. However, with the formation of new-type power systems, the proportion of synchronous generators is reduced and the strength of power grids is weakened, which brings challenges to grid-following inverters.

[0003] If the future power system is entirely composed of power electronic converters, it will not be able to operate without voltage sources, so part of the photovoltaic storage inverters need to be changed into voltage source type. Grid-forming inverters emerge as the times require. Grid-forming inverters can autonomously build AC side output voltage and adapt to islanded and extremely weak grid environments, but they need to be comprehensively analyzed in terms of stability under different grid strengths and disturbance forms. VSG technology has become a research hotspot due to its characteristics of simplified control parameters, easy grid connection and easy integration with other strategies. VSG technology can simulate the operation mechanism of synchronous generators, thereby enhancing the stability of power systems. Traditional VSG control strategies have poor robustness, so it is of important theoretical and practical significance to study parameter adaptive control technology and analyze the virtual inertia characteristics of VSG inverters, optimize parameters and control methods under multiple working conditions, so as to improve the grid stability and response speed.

[0004] DC bus capacitors play a crucial role in photovoltaic inverters and virtual synchronous generator (VSRG) systems. As a core energy storage component, they not only buffer energy, smoothing out the random and intermittent fluctuations in photovoltaic output power, but also maintain the stability of the DC bus voltage by storing charge, providing a constant DC voltage platform for the inverter and ensuring the continuity of AC-DC energy conversion. Furthermore, DC bus capacitors effectively filter high-frequency harmonic currents, reducing harmonic pollution to the power grid. For VSG systems, the stability of the DC bus voltage is fundamental to achieving virtual inertia, active power, and reactive power control, directly affecting the accuracy of grid frequency and voltage regulation. Significant fluctuations in the capacitor voltage will cause the inverter input voltage to exceed the safe operating range, triggering protection shutdowns and even damaging power devices. Simultaneously, it will disrupt the VSG's synchronization mechanism, reducing the system's dynamic response performance. Therefore, maintaining the stability of the DC bus capacitor voltage is key to ensuring the stable operation of photovoltaic-storage VSG systems and improving power quality, and it is also an important technological direction for improving the stability of future high-proportion renewable energy power systems. Summary of the Invention

[0005] To address the problem of preventing overcharging, over-discharging, and excessive voltage fluctuations in the DC bus capacitor that could lead to system instability, this invention provides a virtual synchronous generator adaptive adjustment and control method that considers the voltage stability of the DC bus capacitor.

[0006] The present invention provides an adaptive adjustment and control method for a virtual synchronous generator, comprising:

[0007] Step 1: Obtain the three-phase voltage U at the load end of the photovoltaic-storage grid-connected system. abc Three-phase current I abc And the voltage fluctuation signal ΔV of the DC-side bus capacitor of the VSG inverter. dc ;

[0008] Step 2: Based on the obtained three-phase voltage U abc Three-phase current I abc Obtain the output power response signal curve of the VSG inverter;

[0009] Step 3: Based on the output power response signal curve and the power reference value, obtain the system angular frequency change rate through the VSG active-frequency loop. With the change in angular frequency Δω;

[0010] Step 4: Based on the system's angular frequency change rate The change in angular frequency Δω and the voltage fluctuation signal ΔV dc The virtual moment of inertia coefficient J of the VSG active-frequency loop is dynamically adjusted to generate the actual angular frequency ω of the VSG inverter. mcombining the voltage reference value U with the electromotive force E generated by the virtual synchronous generator ref ;

[0011] Step five: inputting the voltage reference value U into the control module of the optical storage grid-connected system to generate a PWM signal to control the VSG inverter. ref

[0012] As preferred, the virtual rotational inertia coefficient of the VSG active-frequency loop is dynamically adjusted according to a segmented function in step four, and the segmented function is:

[0013]

[0014] wherein J0 is the virtual rotational inertia coefficient value when the optical storage grid-connected system is stably running; Δt is the running time of the optical storage grid-connected system; K0 is the threshold value of Δω change, and K1 is the threshold value of dω / dt change, K0 and K1 are used to prevent the error influence caused by the slight disturbance; P jΔVdc = ΔV dc · P j , P j represents the optical storage bus capacitance voltage regulation coefficient, j = 0, 1, 2, T i is the inertia time constant, i = 1, 2, s is the Laplace variation operator.

[0015] As preferred, the setting of J0 is:

[0016] during the stable running of the optical storage grid-connected system, and the following is met:

[0017]

[0018] wherein P max is the maximum active power output by the optical storage grid-connected system, and ω is the angular frequency.

[0019] As preferred, in the VSG active-frequency loop, the angular frequency ω m of the VSG inverter is obtained by using the VSG virtual speed equation and the VSG rotor motion equation.

[0020] The VSG virtual speed equation is: P m = P ref + K ω (ω0- ω m )

[0021] wherein P m is the actual output mechanical power of the VSG, P ref is the active power reference value, K ω is the active-frequency droop control coefficient, and ω0 is the rated angular velocity. ​

[0022] The VSG rotor motion equation is:

[0023]

[0024] wherein T m is the VSG mechanical torque, T e is the VSG electromagnetic torque, and D is the VSG virtual damping coefficient.

[0025] As a preferred, in the VSG active-frequency loop, the electromotive force E generated by the virtual synchronous generator is obtained by using the VSG stator electromagnetic equation, and the VSG stator electromagnetic equation is:

[0026]

[0027] wherein U is the inverter output voltage, I is the virtual synchronous generator stator current, R a is the virtual resistance, X a is the virtual inductance, and j is the imaginary part.

[0028] As a preferred, the setting of the VSG virtual damping coefficient D is:

[0029] During the stable operation of the photovoltaic energy storage grid-connected system, the setting of D satisfies dω / dt=0 and follows the inequality:

[0030]

[0031] wherein T m max is the maximum mechanical torque of the system, ω max is the maximum allowable angular frequency offset, and ω ref is the reference angular frequency offset.

[0032] As a preferred, the step two comprises:

[0033] The three-phase voltage U abc , the three-phase current I abc and the corresponding phase power factor are multiplied to obtain the instantaneous power of each phase;

[0034] The instantaneous power of each phase is added to obtain the instantaneous output power response signal, and the output power response signal curve is obtained by plotting the operation time as the horizontal coordinate and the instantaneous output power as the vertical coordinate.

[0035] The beneficial effects of the present application, in the process of system operation, the light storage grid-connected power generation system considers the influence of the DC bus capacitor voltage fluctuation value on the virtual moment of inertia according to the power angle characteristic and the rotor angular frequency change of the VSG inverter, so as to carry out adaptive adjustment. Compared with the traditional adaptive adjustment control method, the method can guarantee the stable operation of the light storage VSG system, realize the optimization of system power response, is the key to improve power quality, and is also an important technical direction to improve the stability of future high proportion of renewable energy power system. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 A light storage VSG inverter grid-connected system structure diagram is provided for the present application.

[0037] Figure 2 A power angle characteristic and rotor angular frequency change curve diagram of the light storage VSG inverter is provided for the present application.

[0038] Figure 3 A light storage system residual power state SOC and virtual moment of inertia coefficient interaction mechanism diagram is provided for the present application.

[0039] Figure 4 A virtual moment of inertia coefficient adaptive dynamic adjustment control block diagram considering the light storage SOC is provided for the present application.

[0040] Figure 5 A light storage VSG grid-connected system output active power response diagram caused by sudden increase of light storage VSG demand active power is provided for the present application.

[0041] Figure 6 An output power response diagram under different control strategies is provided for the present application. DETAILED DESCRIPTION

[0042] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0043] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0044] The present application will be further described below with reference to the drawings and specific embodiments, but not as a limitation of the present application.

[0045] The adaptive adjustment control method of the virtual synchronous generator in the present embodiment comprises:

[0046] Step 1, obtaining three-phase voltage U of load end of the optical storage grid-connected system abc , three-phase current I abc , and voltage fluctuation value signal ΔV of DC bus capacitor of the VSG inverter dc ;

[0047] Specifically, the three-phase voltage U abc includes a-phase voltage, b-phase voltage and c-phase voltage; the three-phase current I abc includes a-phase current, b-phase current and c-phase current.

[0048] Step 2, obtaining output power response signal curve of the VSG inverter according to the obtained three-phase voltage U abc , three-phase current I abc ;

[0049] Specifically, multiplying the three-phase voltage U abc , three-phase current I abc and corresponding phase power factor, the instantaneous power of each phase is obtained; the instantaneous output power response signal is obtained by adding the instantaneous power of each phase, and the output power response signal curve is obtained by plotting the running time as the horizontal coordinate and the instantaneous output power as the vertical coordinate.

[0050] Step 3, obtaining system angular frequency change rate and angular frequency change amount Δω according to the output power response signal curve and the power reference value through the VSG active-frequency loop.

[0051] According to the power angle characteristic and rotor angular frequency change curve of the VSG inverter shown in Figure 2 , a change cycle is divided into four stages as shown in Figure 3 for analysis:

[0052] First stage: power rising period, actual angular frequency ω m is greater than the reference value V ref , the angular frequency change rate is greater than 0, and the absolute value of the angular frequency change rate first rapidly increases and then decreases to 0, and the virtual moment of inertia coefficient J is appropriately increased to suppress the rapid change of the angular frequency change rate.

[0053] Second stage: power rising period, actual angular frequency ω m is greater than the reference value V ref , the angular frequency change rate is less than 0, and the absolute value of the angular frequency change rate first shows a gradually increasing trend and then changes to a gradually decreasing trend, and the virtual moment of inertia coefficient J is appropriately reduced to make the actual angular frequency consistent with the reference value as soon as possible.

[0054] Third stage: power falling period, actual angular frequency ωm Less than the reference value V ref angular frequency change rate Less than 0, rate of change of angular frequency The absolute value first increases rapidly and then decreases to 0. In order to suppress the trend of the angular frequency accelerating in the opposite direction and deviating from the reference value, the virtual rotational inertia coefficient J should be appropriately increased.

[0055] Fourth stage: Power decline period, actual angular frequency ω m Less than the reference value V ref angular frequency change rate Greater than 0, rate of change of angular frequency The absolute value first shows a gradual increasing trend and then changes to a gradual decreasing trend. In order to accelerate the recovery of the actual angular frequency to the reference value, the virtual rotational inertia coefficient J should be appropriately reduced.

[0056] in accordance with Figure 2 The power angle characteristics and rotor angular frequency variation curves of the VSG inverter shown are analyzed by dividing one variation cycle into four stages. The interaction between the DC bus capacitor voltage fluctuation and the VSG virtual moment of inertia characteristics is then analyzed. Figure 3 Based on the DC bus capacitor voltage fluctuation signal obtained in step 1 and the system angular frequency change rate and angular frequency change amount described in step 3, and based on the results, a virtual synchronous generator adaptive adjustment and control method considering the DC bus capacitor voltage stability is implemented. Its dynamic adjustment block diagram is shown below. Figure 4 As shown.

[0057] Specifically, the VSG active-frequency loop includes:

[0058] The electromagnetic equations of the VSG stator are expressed as follows:

[0059] In the formula, E is the electromotive force generated by the virtual synchronous generator, U is the inverter output voltage, I is the stator current of the virtual synchronous generator, and R... a X is a virtual resistance. a This is a virtual inductance.

[0060] Based on the active frequency droop characteristic of synchronous generators, a VSG virtual speed governor is established, which can be expressed as the following equation:

[0061] P m =P ref +K ω (ω0-ω m )

[0062] In the formula, P m P represents the actual mechanical power output of the VSG. ref K is the active power reference value. ωω0is the rated angular speed for the active-frequency droop coefficient;

[0063] The VSG rotor motion equation combined with the second-order transient model of the salient pole synchronous generator, and assuming the pole pair number as 1, can be expressed as:

[0064]

[0065] In the formula, T m is the VSG mechanical torque, T e is the VSG electromagnetic torque, and D is the VSG virtual damping coefficient;

[0066] Step 4, according to the system angular frequency change rate and the angular frequency change amount Δω and the voltage fluctuation value signal ΔV dc The virtual inertia coefficient J of the VSG active-frequency loop is dynamically adjusted to generate the actual angular frequency ω m of the VSG inverter, and the reference voltage phase signal θ is combined with the electromotive force E generated by the virtual synchronous generator to synthesize the voltage reference value U ref .

[0067] The mutual influence relationship between the DC bus capacitor voltage fluctuation value of the photovoltaic energy storage system and the virtual inertia characteristic of the VSG is analyzed, and a virtual synchronous generator adaptive adjustment control method considering the DC bus capacitor voltage is implemented according to the results. The virtual inertia coefficient of the VSG active-frequency loop is dynamically adjusted according to the piecewise function, which is:

[0068]

[0069] Wherein, J0is the virtual inertia coefficient value of the photovoltaic energy storage system when it is stable; Δt is the running time of the photovoltaic energy storage system; K0is the threshold value of Δω change, K1is the threshold value of dω / dt change, K0and K1are used to prevent the influence of errors caused by small disturbances; P jΔVdc = ΔV dc · P j , P j represents the photovoltaic energy storage bus capacitor voltage adjustment coefficient, j = 0, 1, 2, T i is the inertia time constant, i = 1, 2, s is the Laplace variation operator.

[0070] ΔV dc = V dc -V ref , wherein V dc is the actual value of the DC bus capacitor voltage, V ref is the reference value of the DC bus capacitor voltage. ΔV dcThe DC bus capacitor voltage fluctuation value is too high or too low, which will adversely affect the charging and discharging efficiency and stability of the optical storage system. Therefore, the interaction between the DC bus capacitor voltage stability and the virtual inertia characteristics of the optical storage VSG should be deeply studied, and the dynamic fluctuation of the DC bus capacitor voltage value should be fully considered in the process of implementing the adaptive parameter adjustment control strategy to ensure that the overall performance of the optical storage grid-connected system is not affected, and then the grid-connected operation is more stable and reliable. The inertia link is added in front of the change rate of dω / dt, which has two purposes: one is to deal with the problem of inconsistent dynamic characteristics of energy storage equipment and distributed power caused by sudden change of dω / dt, because the energy storage equipment has a certain time lag in releasing energy, and cannot meet the energy demand at the moment of dω / dt mutation; the second is to alleviate the sharp change of virtual rotational inertia coefficient J value (i.e. spike phenomenon) caused by frequent fluctuations of dω / dt near the critical value K1, so as to realize a more stable adjustment process.

[0071] Step 5, the voltage reference value U ref is input into the control module of the optical storage grid-connected system to generate a PWM signal to control the VSG inverter, thereby realizing effective control of the VSG inverter of the optical storage system.

[0072] The embodiment proposes an adaptive virtual rotational inertia control method considering the stability of the DC bus capacitor voltage of the optical storage system. During system operation, the optical storage grid-connected power generation system considers the influence of the DC bus capacitor voltage fluctuation value on the virtual rotational inertia according to the power angle characteristics and rotor angular frequency change of the VSG inverter, and adjusts adaptively. Therefore, it can prevent the output of the optical storage system power from being limited and other problems, and ensure the overall performance of the optical storage grid-connected power generation system is not affected, and realize system power response optimization. Compared with the traditional adaptive adjustment control method, the method can ensure the stable operation of the optical storage VSG system and realize system power response optimization, which is the key to improving power quality and an important technical direction for improving the stability of future high proportion of renewable energy power systems.

[0073] The setting of VSG virtual damping coefficient D in the embodiment is:

[0074] During stable operation of the optical storage grid-connected system, dω / dt=0 is satisfied, and the setting of D follows the inequality:

[0075]

[0076] In the formula: T m max is the maximum mechanical torque of the system, ω max is the maximum allowable angular frequency offset; ω ref is the reference angular frequency offset.

[0077] The setting of J0 is:

[0078] During the stable operation of the grid-connected optical storage system, the following is met:

[0079]

[0080] wherein, P max is the maximum active power output by the grid-connected optical storage system, and ω is the angular frequency.

[0081] The working conditions of this embodiment are set as follows:

[0082] In the initial state, the photovoltaic system maintains maximum power output of 10 KW, the DC bus capacitor voltage reference value is set to 800 V, the local load nominal line voltage is 380 V, the rated frequency is 50 Hz, and the demand active power is set to 10 KW.

[0083] From 0 to 0.5 s, the active power reference value of the optical storage VSG inverter is set to 10 KW, at this time the demand active power of the local load can be fully provided by the photovoltaic system, and the energy storage system does not charge or discharge.

[0084] At 0.5 s, the active power reference value of the optical storage VSG inverter suddenly changes to 20 KW, at this time the energy storage system compensates for the 10 KW energy difference, and the optical storage system jointly supplies energy to the rear system, the active power response curve of the grid-connected optical storage VSG caused by the sudden increase of the demand active power of the optical storage VSG is as shown in Figure 6 After the sudden change of the active power reference value, the system produces fluctuations, but after the first frequency regulation process of the VSG corresponding control method, it still maintains stable operation.

[0085] The VSG control loop module parameters are set as shown in Table 1:

[0086] Table 1 VSG control loop module parameters

[0087]

[0088]

[0089] As shown in Figure 6The adaptive adjustment control method of the virtual synchronous generator in the embodiment and the ordinary adaptive control method are shown, and the power response curves after the system fluctuation are compared. As shown in the figure, after the active power reference value is suddenly changed to 20KW at 0.5s, the active power fluctuation in the frequency modulation process of the system adopting the control method described in the patent is smaller than that of the ordinary adaptive control method, the active power overshoot is smaller, the system is recovered to stability faster, the adjustment time is shorter, the adjustment curve slope is more gentle, the influence of the DC bus capacitor voltage fluctuation value on the virtual moment of inertia is considered, the system power response optimization is successfully realized, and the system instability phenomenon is prevented.

[0090] While the application has been described with reference to particular embodiments, it will be understood that the examples are for illustration only and that the principles and applications of the present application can be employed in many other arrangements. It will be appreciated that many modifications can be made to the example embodiments described above, and that other arrangements can be devised without departing from the spirit and scope of the present application as defined by the appended claims. It will be appreciated that features described with reference to individual embodiments can be used in other embodiments described herein.

Claims

1. A method for adaptive regulation control of a virtual synchronous generator, characterized in that, The method comprises: Step one: obtain the three-phase voltage U of the load end of the optical storage grid-connected system abc , three-phase current I abc , and the voltage fluctuation value signal ΔV of the DC side bus capacitor of the VSG inverter dc ; Step two: according to the obtained three-phase voltage U abc , three-phase current I abc Get the output power response signal curve of the VSG inverter; Step three: get the system angular frequency change rate according to the output power response signal curve and power reference value through VSG active-frequency loop and the angular frequency change amount Δω; Step four: according to the system angular frequency rate of change With the angular frequency change amount Δω and the voltage fluctuation value signal ΔV dc The virtual moment of inertia coefficient J of the dynamic adjustment VSG active-frequency ring, generates the actual angular frequency ω of the VSG inverter m With the reference voltage phase signal θ, combined with the electromotive force E generated by the virtual synchronous generator to synthesize the voltage reference value U ref ; Step five: the voltage reference value U ref is input into the control module of the optical storage grid-connected system to generate a PWM signal to control the VSG inverter; In step four, the virtual moment of inertia coefficient of the VSG active-frequency loop is dynamically adjusted according to a segmented function, and the segmented function is: Wherein, J0 is the virtual moment of inertia coefficient value when the light storage grid-connected system is stable; Δt is the light storage grid-connected system running time; K0 is the threshold value of Δω change, K1 is the threshold value of dω / dt change, K0, K1 are used to prevent the error influence caused by small disturbance; P jΔVdc = ΔV dc ·P j , P j Indicates the light storage bus capacitance voltage regulation coefficient, j=0, 1, 2, T i Is the inertia time constant, i=1, 2, s is the Laplace change operator.

2. The method of adaptive regulation control of a virtual synchronous generator according to claim 1, characterized in that, The setting of J0 is: During the stable operation of the grid-connected photovoltaic energy storage system, the following conditions are met: where P max is the maximum active power output of the optical storage grid-connected system, and ω is the angular frequency.

3. The method of adaptive regulation control of a virtual synchronous generator according to claim 1, characterized in that, In the VSG active-frequency loop, the angular frequency ω of the VSG inverter is obtained by using the VSG virtual speed equation and the VSG rotor motion equation m a reference voltage phase signal θ; The VSG virtual speed regulation equation is: P m = P ref + K ω (ω0-ω m ) In the formula, P m is the actual output mechanical power of the VSG, P ref is the active power reference value, K ω is the active-frequency droop control coefficient, and ω0is the rated angular velocity. The VSG rotor motion equation is: where T m is the VSG mechanical torque, T e is the VSG electromagnetic torque, and D is the VSG virtual damping coefficient.

4. The method of adaptive regulation control of a virtual synchronous generator according to claim 1, characterized in that, In the VSG active-frequency loop, the electromotive force E generated by the virtual synchronous generator is obtained by using a VSG stator electromagnetic equation, and the VSG stator electromagnetic equation is: where U is the inverter output voltage, I is the virtual synchronous generator stator current, R a is a virtual resistance, X a is a virtual inductance, and j is the imaginary part.

5. The method of adaptive regulation control of a virtual synchronous generator according to claim 3, characterized in that, The setting of the VSG virtual damping coefficient D is: During the stable operation of the grid-connected photovoltaic energy storage system, the following conditions are met: dω / dt=0, and the setting of D follows the inequality: In the formula: T mmax is the maximum mechanical torque of the system, ω max is the maximum angular frequency offset allowed; ω ref is the reference angular frequency offset.

6. The VSG adaptive regulation control method of claim 1, wherein, Step two comprises: The three-phase voltage U abc , the three-phase current I abc and the corresponding phase power factor are multiplied to obtain the instantaneous power of each phase. The instantaneous output power response signals are obtained by adding the instantaneous powers of the phases, taking the operation time as the horizontal coordinate and taking the instantaneous output power as the vertical coordinate to plot an output power response signal curve.

7. A computer-readable storage device storing a computer program, the computer program comprising instructions that, when executed by a computer, cause the computer to perform the method of any one of claims 1-6. The computer program is executed by the processor to realize the steps of the adaptive adjustment control method of the virtual synchronous generator according to any one of claims 1 to 6.

8. A virtual synchronous generator adaptive regulation control device comprising a storage device, a processor, and a computer program stored in the storage device and executable on the processor, characterized in that, The processor executes the computer program to realize the steps of the adaptive adjustment control method of the virtual synchronous generator according to any one of claims 1 to 6.

9. A computer program product comprising a computer program, characterized in that, The computer program is executed by the processor to realize the steps of the adaptive adjustment control method of the virtual synchronous generator according to any one of claims 1 to 6.

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