Control method and device for dynamic response optimization of virtual synchronous machine and electronic equipment

Abstract

The invention discloses a control method and device for dynamic response optimization of a virtual synchronous machine and electronic equipment, and belongs to the technical field of new energy power generation. The method comprises the following steps: acquiring a grid-connected point voltage of an inverter; judging whether the voltage of the grid-connected point is less than M times of the rated voltage of the power grid, M belongs to (0, 1); responding to the condition that the grid-connected point voltage is less than M times of the rated voltage of the power grid, and accessing a feedforward link based on the angular frequency difference; and responding to the condition that the grid-connected point voltage is greater than or equal to M times of the rated voltage of the power grid, and cutting off a feedforward link based on the angular frequency difference. According to the method, overshoot can be suppressed, the active response speed can be improved, phase angle overshoot under the working condition of sudden drop of the power grid voltage can be reduced, and the requirement for the working condition of sudden drop of the power grid voltage during grid connection of the grid-forming inverter is met.

Description

Technical Field

[0001] The present invention belongs to the technical field of renewable energy power generation, and in particular relates to a control method, a device and an electronic device for optimizing the dynamic response of a virtual synchronous machine. Background Art

[0002] Active loop control in traditional virtual synchronous machine (VSG) control technology is often composed of basic damping control and inertia control. However, basic damping control and inertia control can no longer meet the grid's requirements for the active response speed of grid-connected inverters under grid voltage drop conditions; in addition, the frequency modulation coefficient and damping coefficient during steady-state operation make it difficult for virtual synchronous machines to effectively suppress phase angle overshoot under grid voltage drop conditions. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a control method, device and electronic equipment for optimizing the dynamic response of a virtual synchronous machine in view of the above-mentioned deficiencies in the prior art. For the active power response under the condition of a sudden drop in the grid voltage, the method can suppress overshoot, improve the active power response speed, and reduce the phase angle overshoot under the condition of a sudden drop in the grid voltage, which meets the requirements of the grid-connected inverter facing the condition of a sudden drop in the grid voltage.

[0004] In a first aspect, the present invention provides a control method for optimizing the dynamic response of a virtual synchronous machine, comprising: obtaining the grid connection point voltage of the inverter; determining whether the grid connection point voltage is less than M times the rated voltage of the grid, M∈(0,1); in response to the grid connection point voltage being less than M times the rated voltage of the grid, connecting a feedforward link based on an angular frequency difference; in response to the grid connection point voltage being greater than or equal to M times the rated voltage of the grid, cutting off the feedforward link based on the angular frequency difference.

[0005] Preferably, in response to the grid connection point voltage being greater than or equal to M times the rated voltage of the grid, the feedforward link based on the angular frequency difference is cut off, specifically including: in response to the grid connection point voltage being greater than or equal to M times the rated voltage of the grid and the maintenance time is greater than a preset time, the feedforward link based on the angular frequency difference is cut off.

[0006] Preferably, the access to the feedforward link based on the angular frequency difference specifically includes: obtaining the active power value output by the inverter; substituting the active power value output by the inverter, the reference active power value, the feedback coefficient, the virtual inertia, and the reference angular frequency value into the rotor motion equation to obtain the angular frequency difference; and determining the output voltage phase angle of the inverter according to the angular frequency difference and the feedforward coefficient.

[0007] Preferably, determining the output voltage phase angle of the inverter based on the angular frequency difference and the feedforward coefficient specifically includes: adding the angular frequency difference to a reference angular frequency value to obtain a target angular frequency value; integrating the target angular frequency value, and adding the product of the angular frequency difference and the feedforward coefficient to obtain the output voltage phase angle of the inverter.

[0008] Preferably, after determining the output voltage phase angle of the inverter, the control method further comprises: subtracting the grid voltage phase angle from the output voltage phase angle to obtain a target power angle; and multiplying the target power angle by a target transfer function to obtain an active power value output by the inverter, wherein the target transfer function satisfies:

[0009]

[0010] E is the output voltage of the inverter, V g is the amplitude of the grid voltage, X g is the grid inductive reactance, sin is the sine function.

[0011] Preferably, M=0.9.

[0012] Preferably, before acquiring the active power value output by the inverter, the control method further comprises: adding a proportional coefficient to the product of an integral coefficient and an integral operation to obtain a feedforward coefficient, wherein both the integral coefficient and the proportional coefficient are greater than 0.

[0013] Preferably, the preset duration has a value range of greater than 2 seconds.

[0014] In a second aspect, the present invention further provides a control device for optimizing the dynamic response of a virtual synchronous machine, comprising an acquisition module, a judgment module and a control module.

[0015] An acquisition module is used to acquire the grid connection point voltage of the inverter. A judgment module is connected to the acquisition module and is used to judge whether the grid connection point voltage is less than M times the rated voltage of the grid, M∈(0,1). A control module is connected to the judgment module and is used to connect the feedforward link based on the angular frequency difference in response to the grid connection point voltage being less than M times the rated voltage of the grid, and to cut off the feedforward link based on the angular frequency difference in response to the grid connection point voltage being greater than or equal to M times the rated voltage of the grid.

[0016] In a third aspect, the present invention further provides an electronic device, comprising: a memory and a processor, wherein the memory and the processor are communicatively connected to each other, computer instructions are stored in the memory, and the processor executes the control method for optimizing the dynamic response of the virtual synchronous machine described in the first aspect by executing the computer instructions.

[0017] The control method, device and electronic device for optimizing the dynamic response of a virtual synchronous machine provided by the present invention, when the grid-connected point voltage of the inverter is less than M multiples of the rated voltage of the power grid, a feedforward link based on the angular frequency difference is connected, that is, the angular frequency difference is fed forward to the phase angle link during the dynamic adjustment process, which equivalently increases the transient damping of the system, improves the transient stability of the system, and enhances the response performance. Also, when the grid-connected point voltage is greater than or equal to M multiples of the rated voltage of the power grid, the feedforward link based on the angular frequency difference is cut off, that is, the feedforward link is automatically cut off during steady-state operation, so as not to affect the small signal performance of the system. Thereby, overshoot suppression is achieved, and the active power response speed is improved. At the same time, the phase angle overshoot under the condition of sudden drop in the power grid voltage is reduced, which meets the requirements of the grid-connected inverter when facing the condition of sudden drop in the power grid voltage. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A schematic diagram of a main circuit of a virtual synchronous machine control architecture according to Embodiment 1 of the present invention;

[0019] Figure 2 A schematic flow chart of a control method for optimizing dynamic response of a virtual synchronous machine according to Embodiment 1 of the present invention;

[0020] Figure 3 This is a block diagram of active power conversion control of an angular frequency difference feedforward virtual synchronous machine according to Embodiment 1 of the present invention;

[0021] Figure 4 This is a block diagram of an angular frequency difference feedforward virtual synchronous machine grid-connected closed-loop control according to Embodiment 1 of the present invention;

[0022] Figure 5 This is a block diagram of a traditional virtual synchronous machine grid-connected closed-loop control according to Embodiment 1 of the present invention;

[0023] Figure 6 Schematic diagram of an equivalent damping curve of Example 1 of the present invention;

[0024] Figure 7 This is a block diagram of active loop control of a variation of an angular frequency difference feedforward virtual synchronous machine according to Embodiment 1 of the present invention;

[0025] Figure 8(a) is a graph showing the active power response of a traditional virtual synchronous machine under a sudden voltage drop in the power grid;

[0026] Figure 8(b) is the active response diagram of the angular frequency difference feedforward virtual synchronous machine under the grid voltage sudden drop condition;

[0027] Figure 9(a) is a phase diagram of a traditional virtual synchronous machine under a grid voltage sudden drop condition;

[0028] Figure 9(b) is a phase diagram of the angular frequency feedforward virtual synchronous machine under the grid voltage sudden drop condition;

[0029] Fig.10 This is a schematic diagram of the structure of a control device for optimizing the dynamic response of a virtual synchronous machine according to Embodiment 2 of the present invention. DETAILED DESCRIPTION

[0030] In order to enable those skilled in the art to better understand the technical solution of the present invention, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0031] It should be understood that the specific embodiments and drawings described herein are only used to explain the present invention rather than to limit the present invention.

[0032] It can be understood that, in the absence of conflict, the various embodiments of the present invention and the various features in the embodiments can be combined with each other.

[0033] It can be understood that, for the convenience of description, the drawings of the present invention only show the parts related to the present invention, while the parts irrelevant to the present invention are not shown in the drawings.

[0034] It can be understood that each unit and module involved in the embodiments of the present invention may correspond to only one physical structure, or may be composed of multiple physical structures, or multiple units and modules may be integrated into one physical structure.

[0035] It can be understood that, without conflict, the functions and steps marked in the flowcharts and block diagrams of the present invention may occur in an order different from that marked in the drawings.

[0036] It is understood that the flowcharts and block diagrams of the present invention illustrate the possible architectures, functions, and operations of the systems, devices, equipment, and methods according to the various embodiments of the present invention. Each box in the flowchart or block diagram may represent a unit, module, program segment, or code, which contains executable instructions for implementing the specified functions. Moreover, each box or combination of boxes in the block diagram and flowchart may be implemented by a hardware-based system that implements the specified functions, or may be implemented by a combination of hardware and computer instructions.

[0037] It can be understood that the units and modules involved in the embodiments of the present invention can be implemented by software or hardware. For example, the units and modules can be located in a processor.

[0038] Embodiment 1:

[0039] The control method for optimizing the dynamic response of a virtual synchronous machine provided in the present embodiment is essentially a virtual synchronous machine control technology based on angular frequency difference feedforward. The angular frequency difference feedforward virtual synchronous machine that appears later is equivalent to the control method for optimizing the dynamic response of a virtual synchronous machine in the present embodiment. The control method can be applied to a controller in an inverter, that is, the control method can be executed by a controller in the inverter.

[0040] It should be noted that the inverter in this embodiment is controlled by a virtual synchronous machine (VSG). Figure 1 The main circuit of the virtual synchronous machine control architecture shown in the figure, E and θ are the amplitude and phase angle of the inverter output voltage, L f , R f and C f They are the filter inductance, parasitic resistance and capacitance, R g and L g are the equivalent resistance and inductance between the inverter and the grid, V g is the amplitude of the grid voltage.

[0041] like Figure 2 As shown, this embodiment provides a control method for optimizing the dynamic response of a virtual synchronous machine, including: obtaining the grid-connected point voltage of the inverter; judging whether the grid-connected point voltage is less than M times the rated voltage of the grid, M∈(0,1); in response to the grid-connected point voltage being less than M times the rated voltage of the grid, connecting a feedforward link based on an angular frequency difference; in response to the grid-connected point voltage being greater than or equal to M times the rated voltage of the grid, removing the feedforward link based on an angular frequency difference.

[0042] In this embodiment, the grid connection point voltage is the real-time voltage at the connection point between the inverter and the grid, and the voltage signal can be collected by a voltage transformer or other voltage sensor module. The grid connection point voltage may fluctuate, especially when the load changes or a fault occurs. In this embodiment, the grid connection point voltage of the inverter is first obtained, and then the grid connection point voltage is judged whether it is less than M times the rated voltage of the grid. If the judgment result is yes, the feedforward link based on the angular frequency difference is connected. If the judgment result is no, the feedforward link based on the angular frequency difference is cut off, wherein the value range of M includes (0,1), so that the angular frequency difference can be fed forward to the phase angle link during the dynamic adjustment process, which is equivalent to increasing the transient damping of the system, improving the transient stability of the system, and improving the response performance. And, the feedforward link is automatically cut off during steady-state operation, so as not to affect the small signal performance of the system. Finally, the overshoot is suppressed, the active response speed is improved, and the phase angle overshoot under the condition of sudden drop of the grid voltage is reduced, which meets the requirements of the grid-type inverter when facing the sudden drop of the grid voltage when it is connected to the grid. Since it is only enabled during the regulation process, it does not affect the steady-state performance of the system. The access and removal control of this embodiment can improve the response effect of the system under low voltage ride-through conditions. Through this switching control, the system has different response characteristics under steady-state conditions and low voltage ride-through conditions, thereby better adapting to the needs under the two conditions.

[0043] Optionally, in response to the grid connection point voltage being greater than or equal to M times the rated voltage of the grid, the feedforward link based on the angular frequency difference is cut off, specifically including: in response to the grid connection point voltage being greater than or equal to M times the rated voltage of the grid and the maintenance time is greater than a preset time, the feedforward link based on the angular frequency difference is cut off.

[0044] In this embodiment, when the voltage at the grid connection point is greater than or equal to M times the rated voltage of the grid, and the maintenance time of this voltage state is greater than the preset time, the feedforward link based on the angular frequency difference is cut off. By setting a maintenance time of a time threshold, unnecessary control responses caused by transient changes can be avoided, which helps to improve the adaptability of the system to normal working conditions and reduce transients caused by frequent switching. In other words, it is ensured that the feedforward link of the angular frequency difference is cut off after the system enters a steady state to avoid system instability during cutting.

[0045] Optionally, a feedforward link based on angular frequency difference is connected, specifically including steps S11-S13:

[0046] S11, obtaining the active power value output by the inverter.

[0047] S12, substituting the active power value output by the inverter, the reference active power value, the feedback coefficient, the virtual inertia, and the reference angular frequency value into the rotor motion equation to obtain the angular frequency difference.

[0048] S13, determining the output voltage phase angle of the inverter according to the angular frequency difference and the feedforward coefficient.

[0049] In this embodiment, in step S11, the output current and voltage can be monitored in real time at the output end of the inverter, and the active power value output by the inverter can be calculated based on the measured current and voltage values. Based on the real-time active power value feedback, it is beneficial to the dynamic adjustment of the system and improve the control accuracy and response speed. In step S12, the reference active power value can be a reference value of the active power of the inverter, the reference angular frequency value can be a reference value of the angular frequency of the output voltage of the inverter, and the angular frequency difference is the frequency error between the angular frequency value of the output voltage of the inverter and the reference angular frequency value. The reference active power value and the reference angular frequency value can be determined according to the actual requirements of the inverter. For example, the reference angular frequency value is 100π; when the inverter is powered by an external power supply, the active power reference value can be set to 0 to save power consumption. By introducing virtual inertia, the change of the output state can be slowed down when the system is disturbed, thereby improving the stability of the system. In step S13, the product of the angular frequency difference and the feedforward coefficient is applied to the inverter output voltage phase angle, and the inverter output voltage phase angle is adjusted to match the system load change. The control method based on the feedforward link of the angular frequency difference is connected under the condition of grid voltage sudden drop. By real-time monitoring and adjusting the inverter output voltage, the system's rapid response capability in dynamic response can be improved, and the stability can be enhanced, ultimately achieving more efficient power transmission and quality control. This control process can significantly improve the grid connection capability and reliability of renewable energy systems such as wind power and photovoltaic power generation.

[0050] Optionally, the output voltage phase angle of the inverter is determined based on the angular frequency difference and the feedforward coefficient, specifically including: adding the angular frequency difference to the reference angular frequency value to obtain a target angular frequency value; integrating the target angular frequency value, and then adding the product of the angular frequency difference and the feedforward coefficient to obtain the output voltage phase angle of the inverter, wherein the feedforward coefficient is greater than 0.

[0051] In this embodiment, Figure 3 The angular frequency difference feedforward virtual synchronous machine active loop control block diagram shown in FIG. 1 is used to convert the active power value P output by the inverter and the reference active power value P ref , feedback coefficient k f , virtual inertia J, reference angular frequency value ω ref Substituting into the rotor motion equation, we get the angular frequency difference Δω, and then compare the angular frequency difference Δω with the reference angular frequency value ω ref The sum is obtained to obtain the target angular frequency value ω, and the value obtained by integrating the target angular frequency value ω is added to the product of the angular frequency difference Δω and the feedforward coefficient k, and finally the output voltage phase angle θ of the inverter is obtained, wherein the feedforward coefficient k is greater than 0. The value of the feedforward coefficient k can be pre-set in the controller of the inverter.

[0052] Another example Figure 3As shown, in response to the grid connection point voltage being greater than or equal to M times the grid rated voltage, the feedforward link based on the angular frequency difference is removed, that is, corresponding to Figure 3 The feed forward coefficient shown is 0 to achieve this cut-off control.

[0053] The angular frequency difference feedforward virtual synchronous machine active loop control technology of this embodiment can be applied to renewable energy grid connection (for example, in the access of renewable energy such as wind energy and solar energy, due to the uncertainty and volatility of their output power, the use of active loop control of virtual synchronous machines can effectively improve the stability and response speed of the system), microgrid management (for example, microgrids usually include multiple distributed power generation sources, and virtual synchronous machine control can achieve coordination between different power generation units and enhance the stability of microgrids in island mode), grid frequency regulation (for example, when the grid frequency fluctuates, the active loop control of the virtual synchronous machine can respond quickly and adjust the output power of the inverter to restore frequency balance) and other application scenarios.

[0054] Optionally, after determining the output voltage phase angle of the inverter, the control method further comprises: subtracting the grid voltage phase angle from the output voltage phase angle to obtain a target power angle; multiplying the target power angle by the target transfer function to obtain an active power value output by the inverter;

[0055] Among them, the target transfer function satisfies:

[0056]

[0057] E is the output voltage of the inverter, V g is the amplitude of the grid voltage, X g is the grid inductive reactance, sin is the sine function.

[0058] In this embodiment, under the premise of inductive lines and small phase angles, a virtual synchronous machine grid-connected closed-loop control block diagram based on angular frequency difference feedforward access and a traditional virtual synchronous machine grid-connected closed-loop control block diagram can be obtained as follows: Figure 4 and Figure 5 As shown. Figure 4 The angular frequency difference feedforward virtual synchronous machine grid-connected closed-loop control block diagram shown in FIG. 1 is based on the output voltage phase angle θ of the inverter and the grid voltage phase angle θ g Determine the target power angle δ, which refers to the power angle output by the active loop. 0 Take the product and get the active power value P output by the inverter.

[0059] For the traditional virtual synchronous machine, the damping factor D depends on the feedback coefficient k of the angular frequency in the active loop. f However, for the virtual synchronous machine of this embodiment, the damping factor D depends not only on the feedback coefficient k of the angular frequency in the active loop f, and is also related to the feedforward coefficient k. And because the study is a low voltage condition, the equivalent damping cannot be analyzed by the transfer function that requires a small phase angle. Therefore, it is necessary to use another method to calculate the damping factor.

[0060] The damping factor D of the virtual synchronous machine can be defined as the inverse of the gain from ΔP to Δω in the virtual synchronous machine. ΔP is P ref The power error between and P, Δω is ω ref The frequency error between and ω, a large damping factor D is conducive to the stability of the virtual synchronous machine. In this way, the equivalent damping factor of the virtual synchronous machine under different feedforward coefficients k can be simulated. The simulation parameters are shown in Table 1.

[0061] Table 1 Simulation parameters

[0062] <![CDATA[P ref ]]> 330kW <![CDATA[ω ref ]]> 100*pi <![CDATA[ω g ]]> 100*pi <![CDATA[V g ]]> 800V J 40.123 <![CDATA[k f ]]> 10024.29

[0063] The equivalent damping factor of the virtual synchronous machine under different feedforward coefficients is simulated, and the simulation results are shown in Table 2 and Figure 6 As shown:

[0064] Table 2 Equivalent damping table

[0065] k D 0.0 10024 0.05 10560 0.075 11353 0.1 11303 0.2 10462 0.3 10332

[0066] From Table 2 and Figure 6 It can be seen that the equivalent damping of the traditional virtual synchronous machine (corresponding to the feedforward coefficient k of 0) is 10024, while the equivalent damping of this embodiment under different feedforward coefficients k is greater than 10024, indicating that the control method of the virtual synchronous machine dynamic response optimization of this embodiment can obtain a larger equivalent damping, that is, in the dynamic adjustment process, the transient damping is equivalently increased, the response speed of the output frequency is reduced, and the increased transient damping is automatically cut off during steady-state operation. It can be further seen that under the parameters of Table 1, when the feedforward coefficient k is 0.075, the maximum equivalent damping can be obtained.

[0067] Optionally, M=0.9.

[0068] In this embodiment, M=0.9 is taken, indicating that the voltage at the grid connection point drops to 90% of the rated voltage of the grid. Based on this threshold, effective determination of the voltage sag condition can be ensured.

[0069] Optionally, before obtaining the active power value output by the inverter, the control method further includes: adding a proportional coefficient to a product of an integral coefficient and an integral operation to obtain a feedforward coefficient, wherein both the integral coefficient and the proportional coefficient are greater than 0.

[0070] In this embodiment, Figure 7The active loop control block diagram of the angular frequency difference feedforward virtual synchronous machine variant shown in the figure is different from the angular frequency difference feedforward virtual synchronous machine in that an integral coefficient is added to the feedforward link to achieve control of the integral coefficient. 1 is the feedforward proportionality factor, k 2 is the feedforward integral coefficient, P ref is the reference active power value, P is the active power value output by the inverter, ω ref is the reference angular frequency value, J is the virtual inertia, k f is the feedback coefficient, θ is the inverter phase angle, V P is the grid connection point voltage of the inverter, and pu is the rated voltage of the grid. This variation can further change the system response characteristics in transient state without affecting the system characteristics in steady state.

[0071] Optionally, the value range of the preset duration is greater than 2 seconds.

[0072] In this embodiment, the feedforward link can be cut off when the grid-connected voltage of the system returns to stability, and the preset time length has a value range greater than 2 seconds, such as 5 seconds. The preset time length can avoid system instability during cutting and avoid frequent switching.

[0073] This embodiment compares the performance of a traditional virtual synchronous machine under a grid voltage sudden drop condition with the control method for optimizing the dynamic response of a virtual synchronous machine of this embodiment (ie, an angular frequency difference feedforward virtual synchronous machine).

[0074] The simulation is performed according to the simulation parameters in Table 3.

[0075] Table 3 Simulation parameters

[0076] <![CDATA[P ref ]]> 330kW <![CDATA[ω ref ]]> 100*pi <![CDATA[ω g ]]> 100*pi <![CDATA[V g ]]> 800V J 40.123 <![CDATA[k f ]]> 10024.29 k 0.1

[0077] (1) Performance comparison of response rate:

[0078] The active power diagrams of the traditional virtual synchronous machine and the virtual synchronous machine of this embodiment under the condition of sudden drop in grid voltage are shown in Figure 8(a) and Figure 8(b). Specifically, when t=40, the grid voltage drops to 0.8 times the rated voltage. As can be seen from Figure 8(a), the peak power of the traditional virtual synchronous machine is 387500w, the overshoot is 17.4%, and the adjustment time (Δ=0.05) is 4.295s. As can be seen from Figure 8(b), the peak power of the angular frequency difference feedforward virtual synchronous machine is 362400w, the overshoot is 9.8%, and the adjustment time (Δ=0.05) is 0.911s.

[0079] Therefore, it can be concluded that, compared with the traditional virtual synchronous machine, the overshoot of the active power response of the angular frequency difference feedforward virtual synchronous machine of this embodiment is smaller, and the adjustment time of the active power response is shorter.

[0080] (2) Performance comparison of phase angle overshoot:

[0081] The phase diagrams of the conventional virtual synchronous machine and the virtual synchronous machine of this embodiment under the condition of grid voltage sudden drop are shown in FIG9(a) and FIG9(b). Specifically, it can be seen from FIG9(a) that when V g =0.8pu, the maximum phase angle is 0.9156; when V g =0.7pu, the maximum phase angle is 1.1994; when V g =0.6pu, the system becomes unstable; when V g =0.55pu, the system becomes unstable. As can be seen from Figure 9(b), when V g =0.8pu, the maximum phase angle is 0.8374; when V g =0.7pu, the maximum phase angle is 1.2319; when V g =0.6pu, the maximum phase angle is 1.5380; when V g When =0.55pu, the system becomes unstable.

[0082] Therefore, it can be concluded that, compared with the traditional virtual synchronous machine, the angular frequency difference feedforward virtual synchronous machine of this embodiment has smaller overshoot of the phase angle response and better transient stability.

[0083] In summary, compared with the traditional virtual synchronous machine, the angular frequency difference feedforward virtual synchronous machine has the first advantage in terms of active response under the condition of grid voltage sag, while achieving the goals of suppressing overshoot and improving response speed. The second advantage is that it reduces the phase angle overshoot under the condition of grid voltage sag, which meets the requirements of the grid-connected inverter when facing the condition of grid voltage sag when connected to the grid.

[0084] The control method for optimizing the dynamic response of the virtual synchronous machine in this embodiment can improve the performance of suppressing overshoot and increasing the response speed of the virtual synchronous machine when responding to active power, and solve the coupling effect of droop control and damping control existing in the active loop of traditional virtual synchronous machine control, thereby achieving a better active power response (suppressing overshoot and increasing response speed at the same time) while reducing the response speed of the output frequency, which meets the requirements of network-type control frequency modulation and inertia support.

[0085] Embodiment 2:

[0086] like Fig.10 As shown, this embodiment provides a control device for optimizing the dynamic response of a virtual synchronous machine, including an acquisition module 11 , a judgment module 12 and a control module 13 .

[0087] The acquisition module 11 is used to acquire the grid connection point voltage of the inverter.

[0088] The judgment module 12 is connected to the acquisition module 11 and is used to judge whether the voltage at the grid connection point is less than M times the rated voltage of the grid, M∈(0,1).

[0089] The control module 13 is connected to the judgment module 12, and is used to connect the feedforward link based on the angular frequency difference in response to the grid connection point voltage being less than M times the grid rated voltage, and to cut off the feedforward link based on the angular frequency difference in response to the grid connection point voltage being greater than or equal to M times the grid rated voltage.

[0090] Optionally, the control module is used to cut off the feedforward link based on the angular frequency difference in response to the grid connection point voltage being greater than or equal to M times the rated voltage of the grid and maintained for a duration greater than a preset duration.

[0091] Optionally, the control module is specifically used to obtain the active power value output by the inverter, and substitute the active power value output by the inverter, the reference active power value, the feedback coefficient, the virtual inertia, and the reference angular frequency value into the rotor motion equation to obtain the angular frequency difference, and to determine the output voltage phase angle of the inverter based on the angular frequency difference and the feedforward coefficient.

[0092] Optionally, the control module is further used to add the angular frequency difference to the reference angular frequency value to obtain a target angular frequency value, and to integrate the target angular frequency value and add the product of the angular frequency difference and the feedforward coefficient to obtain the output voltage phase angle of the inverter.

[0093] Optionally, the control module is further used to subtract the grid voltage phase angle from the output voltage phase angle to obtain a target power angle, and to multiply the target power angle with the target transfer function to obtain an active power value output by the inverter.

[0094] Among them, the target transfer function satisfies:

[0095]

[0096] E is the output voltage of the inverter, V g is the amplitude of the grid voltage, X g is the grid inductive reactance, sin is the sine function.

[0097] Optionally, M=0.9.

[0098] Optionally, the control module is further configured to add a proportional coefficient to a product of an integral coefficient and an integral operation to obtain a feedforward coefficient, wherein both the integral coefficient and the proportional coefficient are greater than zero.

[0099] Optionally, the value range of the preset duration is greater than 2 seconds.

[0100] Embodiment 3:

[0101] This embodiment provides an electronic device, including: a memory and a processor, the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the control method for dynamic response optimization of the virtual synchronous machine described in Example 1 by executing the computer instructions.

[0102] It is to be understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present invention, but the present invention is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A control method for optimizing the dynamic response of a virtual synchronous machine, characterized in that: include: Get the grid connection point voltage of the inverter; Determine whether the grid connection point voltage is less than M times the rated voltage of the grid, M∈(0,1); In response to the grid connection point voltage being less than M times the rated voltage of the grid, a feedforward link based on the angular frequency difference is connected; In response to the grid connection point voltage being greater than or equal to M times the rated voltage of the grid, a feedforward link based on the angular frequency difference is cut off.

2. The method according to claim 1, characterized in that In response to the grid connection point voltage being greater than or equal to M times the rated voltage of the grid, the feedforward link based on the angular frequency difference is cut off, specifically comprising: In response to the grid connection point voltage being greater than or equal to M times the rated voltage of the grid and being maintained for a duration greater than a preset duration, a feedforward link based on the angular frequency difference is cut off.

3. The method according to claim 1, characterized in that The access is based on the feedforward link of the angular frequency difference, specifically including: Get the active power value output by the inverter; Substitute the active power value output by the inverter, the reference active power value, the feedback coefficient, the virtual inertia, and the reference angular frequency value into the rotor motion equation to obtain the angular frequency difference; The output voltage phase angle of the inverter is determined based on the angular frequency difference and the feed-forward coefficient.

4. The method according to claim 3, characterized in that Determining the output voltage phase angle of the inverter according to the angular frequency difference and the feedforward coefficient specifically includes: Add the angular frequency difference to the reference angular frequency value to obtain the target angular frequency value; The target angular frequency value is integrated and then added with the product of the angular frequency difference and the feedforward coefficient to obtain the output voltage phase angle of the inverter.

5. The method according to claim 3, characterized in that: After determining the output voltage phase angle of the inverter, the method further includes: Subtract the grid voltage phase angle from the output voltage phase angle to obtain the target power angle; The target power angle is multiplied by the target transfer function to obtain the active power value output by the inverter. Among them, the target transfer function satisfies: E is the output voltage of the inverter, V g is the amplitude of the grid voltage, X g is the grid inductive reactance, sin is the sine function.

6. The method according to claim 3, characterized in that M＝0.9。 7. The method according to claim 3, characterized in that Before obtaining the active power value output by the inverter, the method further includes: The product of the integral coefficient and the integral operation is added to the proportional coefficient to obtain the feedforward coefficient, wherein the integral coefficient and the proportional coefficient are both greater than 0.

8. The method according to claim 2, characterized in that: The preset duration value range is greater than 2 seconds.

9. A control device for optimizing the dynamic response of a virtual synchronous machine, characterized in that: Including acquisition module, judgment module and control module, The acquisition module is used to obtain the grid connection point voltage of the inverter. A judgment module, connected to the acquisition module, is used to judge whether the grid connection point voltage is less than M times the rated voltage of the grid, M∈(0,1), The control module is connected to the judgment module and is used to switch on the feedforward link based on the angular frequency difference in response to the grid connection point voltage being less than M times the grid rated voltage, and to cut off the feedforward link based on the angular frequency difference in response to the grid connection point voltage being greater than or equal to M times the grid rated voltage.

10. An electronic device, characterized in that: include: A memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the control method for optimizing the dynamic response of a virtual synchronous machine according to any one of claims 1 to 8 by executing the computer instructions.

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