Virtual synchronous inertia and damping coordination control method and system based on damping ratio

Abstract

The invention discloses a damping ratio-based virtual synchronous inertia and damping coordination control method and system. The method comprises the following steps of: constructing a grid-connected small signal model based on virtual synchronous machine control; setting an inertia selection rule according to a power angle curve of a synchronous machine in the grid-connected small signal model; determining an inertia selection range and an adjustment coefficient according to the inertia selection rule; and within the selection range, constructing a virtual synchronous control strategy of damping ratio coordinated optimization inertia and damping according to the adjustment coefficient. Frequency instability caused by too low inertia is avoided, and the stability of a power system is enhanced.

Description

Technical Field

[0001] The present invention belongs to the technical field of power system control, and in particular relates to a virtual synchronous inertia and damping coordinated control method and system based on damping ratio. Background Art

[0002] As distributed generation (DGs) become increasingly important in traditional power grids, the number of power electronic devices increases. As a result, the grid no longer possesses the inertia support provided by traditional synchronous generators, gradually exhibiting characteristics such as "low inertia" and "weak damping." The stability issues caused by this lack of inertia and damping are particularly prominent. Compared to traditional droop control, virtual synchronous generator (VSG) control technology simulates the rotor motion characteristics of traditional power system synchronous generators by controlling power electronic converters. This allows them to have frequency and voltage modulation characteristics while maintaining a certain level of inertia and damping, giving microgrid systems similar resistance to external disturbances as synchronous generators.

[0003] Microgrid VSG control has evolved from fixed moment of inertia and damping control strategies to adaptive virtual parameter control. This has improved the VSG's power response and stability, but has not improved the system's frequency recovery characteristics. Furthermore, the VSG's inertial potential energy comes from its energy storage unit or a small number of renewable energy generation devices with inertial potential energy. Ignoring the constraints imposed by the charge and discharge characteristics of the power-side energy storage unit on the system's virtual inertia has, to a certain extent, lacked engineering application value. Summary of the Invention

[0004] The present invention provides a virtual synchronous inertia and damping coordinated control method and system based on damping ratio and a readable storage medium, which are used to solve the technical problem that the dynamic response of the VSG system output frequency and power is poor, resulting in low engineering practicality of the VSG control technology.

[0005] In a first aspect, the present invention provides a method and system for coordinated control of virtual synchronous inertia and damping based on a damping ratio, comprising:

[0006] Construct a grid-connected small signal model based on virtual synchronous machine control;

[0007] Setting an inertia selection rule according to the power angle curve of the synchronous machine in the grid-connected small signal model;

[0008] Determine the selection range of inertia and the adjustment coefficient according to the inertia selection rule;

[0009] Within the selected range, a virtual synchronous control strategy for coordinating and optimizing inertia and damping by the damping ratio is constructed according to the adjustment coefficient. The expression of the damping ratio is:

[0010]

[0011] Where ξ is the damping ratio, ξ1 is the set early transient damping ratio, which is used to speed up the early response of the system, ξ0 is the set steady-state damping ratio, ξ2 is the set late transient damping ratio, which is used to suppress the late overshoot of the power step response, Δω is the transient value of the angular frequency, T d is the set angular frequency deviation margin, and ΔP is the deviation between the reference active power and the virtual active output power.

[0012] In a second aspect, the present invention provides a method and system for coordinated control of virtual synchronous inertia and damping based on a damping ratio, comprising:

[0013] A first building module is configured to build a grid-connected small signal model based on virtual synchronous machine control;

[0014] a setting module configured to set an inertia selection rule according to a power angle curve of the synchronous machine in the grid-connected small signal model;

[0015] a determination module configured to determine a selection range of inertia and an adjustment coefficient according to the inertia selection rule;

[0016] The second building module is configured to build a virtual synchronous control strategy for coordinated optimization of inertia and damping by the damping ratio according to the adjustment coefficient within the selected range, and the expression of the damping ratio is:

[0017]

[0018] Where ξ is the damping ratio, ξ1 is the set early transient damping ratio, which is used to speed up the early response of the system, ξ0 is the set steady-state damping ratio, ξ2 is the set late transient damping ratio, which is used to suppress the late overshoot of the power step response, Δω is the transient value of the angular frequency, T d is the set angular frequency deviation margin, and ΔP is the deviation between the reference active power and the virtual active output power.

[0019] In a third aspect, an electronic device is provided, comprising: at least one processor, and a memory communicatively connected to the at least one processor, wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the steps of the virtual synchronous control method of the damping ratio coordinated inertia and damping of any embodiment of the present invention.

[0020] In a fourth aspect, the present invention also provides a computer-readable storage medium having a computer program stored thereon. When the program instructions are executed by a processor, the processor executes the steps of the virtual synchronous control method of the damping ratio coordinated inertia and damping of any embodiment of the present invention.

[0021] The present application discloses a virtual synchronous inertia and damping coordinated control method and system based on damping ratio, which analyzes the relationship between the deviation between active power and virtual active output power and frequency differential, and uses it to replace the frequency deviation to achieve continuous adjustment of inertia, avoid the introduction of differential signals, and reduce the introduction of high-frequency noise; by setting the inertia adjustment coefficient selection principle, on the one hand, the adjustment range of inertia is increased, which can better suppress frequency deviation and frequency change rate; on the other hand, it avoids frequency instability caused by too low inertia, and enhances the stability of the power system; a damping ratio coordination strategy is designed, which can reduce overshoot and the number of energy storage charging and discharging times through damping selection, while reducing the adjustment time, accelerating the speed at which power and frequency enter stability, and enhancing stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following is a brief introduction to the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0023] Figure 1 A flowchart of a virtual synchronous control method for coordinating inertia and damping with a damping ratio according to an embodiment of the present invention;

[0024] Figure 2 A closed-loop block diagram of active power control for a virtual synchronous generator (VSG) according to an embodiment of the present invention;

[0025] Figure 3 A pole distribution diagram under inertia damping changes provided by an embodiment of the present invention; Figure 4 The power angle characteristic curve and angular frequency oscillation curve provided by an embodiment of the present invention; Figure 5 A four-quadrant selection criterion for inertia provided in one embodiment of the present invention; Figure 6 A structural block diagram of a virtual synchronous control system for coordinating inertia and damping with a damping ratio provided by one embodiment of the present invention; Figure 7 It is a structural diagram of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0026] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0027] See also Figure 1 , which shows a flowchart of a virtual synchronous control method of a damping ratio coordinated inertia and damping of the present application.

[0028] like Figure 1 As shown in FIG, the virtual synchronous control method of the damping ratio coordinated inertia and damping specifically includes the following steps:

[0029] Step S101: constructing a grid-connected small signal model based on virtual synchronous machine control.

[0030] In this step, the active output power and reactive output power equations of the inverter are established, and the expressions are:

[0031]

[0032] Where S is the output apparent power, P e is the active output power, Q e is the reactive output power, j is the imaginary unit, U g is the grid voltage amplitude, E is the inverter output voltage amplitude, θ is the power angle, X d is the equivalent transmission reactance;

[0033] When the system is in steady state operation, the power angle difference can be approximately regarded as 0, and we can get:

[0034]

[0035] Taking the power angle and the voltage amplitude of the inverter output as independent variables, we can get:

[0036]

[0037] Where J is the virtual inertia, ω0 is the rated angular frequency, D is the damping coefficient, s is the frequency domain factor, Δω(s) is the angular frequency disturbance, and ΔP ref (s) is the active reference disturbance, ΔP e (s) is the active electromagnetic power disturbance, ΔE(s) is the output voltage amplitude disturbance, K s is the reactive loop integral coefficient, K q is the reactive voltage regulation coefficient, ΔQ ref (s) is the reactive reference disturbance, ΔQe (s) is the reactive electromagnetic power disturbance, Δθ(s) is the power angle disturbance, E is the output voltage amplitude, U g is the grid voltage amplitude, θ is the power angle, X d is the equivalent output reactance.

[0038] Eliminate the intermediate variable Δθ(s), through Figure 2 The active power block diagram can be used to obtain the transfer function expression of active power:

[0039]

[0040] Where K p is the primary frequency modulation coefficient, and K is the synchronization coefficient.

[0041] The VSG active closed-loop system is a typical second-order oscillation system. ref and ω g Under disturbance, its grid-connected output characteristics have a design contradiction between regulation speed and oscillation suppression.

[0042] The natural oscillation angular frequency and damping ratio corresponding to a typical second-order oscillation system are:

[0043]

[0044] Where, ω n is the natural oscillation frequency;

[0045] In order to express and analyze the influence of damping and virtual inertia on active transient response, let K p =D1*ω0, K p +Dω0 is recorded as D d ω0, where D d =D1+D,D d is the equivalent damping value after the primary frequency modulation coefficient is equivalent to the damping coefficient, and D1 is the damping value after the primary frequency modulation is equivalent. Therefore, the expression of the damping ratio ξ is:

[0046]

[0047] The damping ratio and natural frequency of the second-order system determine the transient response of the system. The damping ratio ξ reflects the overshoot and oscillation mode of the system, and the natural frequency ω n The response speed of the reaction system. In order to more intuitively analyze the influence of inertia and damping on the system damping ratio and natural frequency, the closed-loop pole diagram under the change of J and D parameters is drawn as follows: Figure 3 As shown. Figure 3As can be seen in the figure, as the inertia coefficient J increases, the system's damping ratio and natural frequency decrease, reducing its ability to suppress oscillations. Simultaneously, the pole approaches the imaginary axis, and the stability margin of the active loop gradually weakens. As the damping coefficient D increases, the system's damping ratio increases, gradually transitioning from an underdamped system to an overdamped one. This slows the system's transient regulation process, but strengthens its ability to suppress oscillations. Therefore, it is necessary to rationally design the inertia and damping coefficients to improve the system's power and frequency transient response.

[0048] Step S102 : setting an inertia selection rule according to the power angle curve of the synchronous machine in the grid-connected small signal model.

[0049] In this step, under grid-connected conditions, when the system reference power jumps, transient power imbalance will occur, which will cause the inverter output power and frequency to oscillate. The specific power angle curve, virtual output power and output frequency oscillation curve during the oscillation process are as follows: Figure 4 shown.

[0050] When the system's power command value changes from P1 to P2, the system's output power will oscillate between points a and c, and eventually stabilize at point b. The entire power and frequency response dynamic process can be divided into the following four processes for analysis: t1 is the first angular frequency extreme moment, t2 is the second angular frequency zero crossing moment, t3 is the second angular frequency extreme moment, and t4 is the second angular frequency zero crossing moment.

[0051] In the process 0-t1, the power difference (the power command value and the output power including the damping power difference) continues to decrease, the system frequency change rate decreases, and the system frequency deviation continues to increase. When the power difference is zero, the frequency deviation reaches the maximum, the output frequency is the maximum value, and the system enters the deceleration process from the acceleration process.

[0052] Therefore, in the process 0-t1, it is considered to increase the system inertia J to slow down the frequency change rate and reduce the frequency deviation.

[0053] During the process t1-t2, the power difference continues to increase, the system frequency change rate increases, and the system frequency deviation continues to decrease. When the frequency difference is 0, the system will enter a deceleration motion, but the output power is still greater than the power command value. The frequency change rate will begin to decrease, the frequency will have a negative deviation, and the system will run in the reverse direction.

[0054] Therefore, consider reducing the system inertia and speeding up the system to reach the rated regulation speed.

[0055] The analysis of the deceleration process t2-t3 and the acceleration process t3-t4 is similar to that of the previous two stages and will not be repeated here. After the four dynamic processes, a new oscillation cycle begins. As the oscillation amplitude decreases, the system eventually stabilizes and enters a new stable operating point, point b.

[0056] From the above analysis, we can see that the selection of damping and inertia will affect the frequency change rate and frequency deviation of the system. In different processes, different damping and inertia should be set to meet the requirements of the system frequency index. The specific inertia adaptive principle is as follows: Figure 5 shown.

[0057] Figure 5 In the equation, Δω=ω-ω0 represents the deviation between the output frequency and the rated frequency, and ΔP represents the deviation between the reference active power and the virtual active output power, namely:

[0058] ΔP=P2-P=P2-D d ω0(ω-ω0)-P e ,

[0059] Where, P is the virtual active output power, P2 is the active reference command jump value, P e is the actual electromagnetic power, ω is the angular frequency actually output by the algorithm;

[0060] We obtain: (ΔP) / (dΔω / dt)=Jω0,

[0061] , satisfying J>0, ω0>0, so AP should have the same sign as the frequency change rate dΔω / dt. Therefore, the power deviation can be used instead of the frequency change rate to partition the four transient processes of the system, and the inertia adaptive control is designed as follows:

[0062] J=J0+k1ΔPΔω,

[0063] Where J is the virtual inertia, J0 is the initial inertia coefficient, k1 is the inertia adjustment coefficient, which is always positive, ΔP is the deviation between the reference active power and the virtual active output power, and Δω is the deviation between the output frequency and the rated frequency.

[0064] This method uses the system's virtual power deviation to adaptively select the inertia coefficient, which can avoid directly derivatizing the frequency. In addition, this method can adaptively adjust the inertia according to the system's four acceleration and deceleration operating ranges to ensure smooth and continuous inertia changes.

[0065] Step S103: determining the inertia selection range and the adjustment coefficient according to the inertia selection rule.

[0066] In this step, the inertia adjustment coefficient is selected:

[0067] During the transient process of power jump, the inertia value should always be positive. Negative inertia will cause the acceleration and deceleration mode of the angle of attack curve to switch, which will affect the stability of the system. The constraint conditions are:

[0068] J=J0+k1(P2-Pe -D d ω0Δω)Δω≥0,

[0069] That is, it satisfies:

[0070] k1≤J0 / |Δω(P2-P e -D d ω0Δω)| max ,

[0071] Where, k1 is the inertia adjustment coefficient;

[0072] The downward quadratic equation system with Δω as the independent variable has a maximum value, so the inertia adjustment coefficient k1 should satisfy:

[0073]

[0074] Where, is the square of the maximum difference between the power command value and the actual output power, and P2 is the active reference command jump value;

[0075] As can be seen from the above, the inertia coefficient adjustment range is limited due to the influence of the selection range of the inertia adjustment coefficient k1, which may cause the frequency change rate to exceed the limit. Based on this, a method of variable adjustment coefficient is proposed.

[0076] according to Figure 5 It can be seen that in the process from the power command value jumping to the stability of the entire system, in the process t1-t2 and the process t3-t4, ΔP*Δω<0. If the inertia adjustment coefficient k1 is too large, the inertia coefficient will be negative, causing system instability. Therefore, in these two stages, the inertia adjustment coefficient k1 should take a smaller value. In the process 0-t1 and the process t2-t3, when ΔP*Δω>0, it is expected that the inertia adjustment coefficient k1 will take a larger value. By increasing the inertia coefficient, the frequency change rate and frequency deviation can be reduced, but the maximum value of the inertia coefficient should still be less than the equivalent maximum inertia constrained by the energy storage unit.

[0077]

[0078] Where k J1 is the negative inertia zone adjustment coefficient, k J2 is the positive inertia adjustment coefficient, ΔP is the deviation between the reference active power and the virtual active output power, and Δω is the deviation between the output frequency and the rated frequency.

[0079] Determination of inertia range:

[0080] To further determine the range of the inertia coefficient, referring to the characteristics of traditional synchronous generators, their natural oscillation frequency is usually between 0.628-15.7 rad / s. The expression of damping ratio and natural oscillation angular frequency can be obtained:

[0081]

[0082] Energy storage unit constraints:

[0083] When adjusting the inertia and damping coefficient of the VSG system, the constraints imposed by the energy storage unit on the VSG parameter range should be considered.

[0084] In addition to supplying energy and regulating VSG frequency, the energy storage system also retains a portion of potential energy to maintain its own state of charge. Therefore, after deducting the energy required to maintain the minimum SOC, the VSG energy balance equation can be obtained as:

[0085]

[0086] Where Cu is the stabilizing voltage and stabilizing capacitance of the energy storage system, SOC is the state of charge of the energy storage system, and SOC is the state of charge of the energy storage system. min The minimum state of charge that needs to be maintained for energy storage;

[0087] Further consider the equivalent capacitance C of the energy storage unit eq 、Maximum charge and discharge rate α max and the rated voltage U of the energy storage unit CN , the equivalent maximum inertia J of the energy storage system can be obtained max The expression:

[0088]

[0089] Where, I CN 、T CN are the rated discharge current and rated discharge time of the energy storage unit respectively;

[0090] Summarizing the above conclusions, the constraints of the energy storage unit on the VSG control parameters can be obtained as follows:

[0091]

[0092] System dynamic frequency constraints:

[0093] The rate of change of frequency (RoCoF) and the maximum frequency deviation are key indicators for measuring frequency stability under disturbances. The RoCoF constraint can be determined by a specific value. Therefore, the RoCoF constraint is used to determine the minimum inertia of the system. The inertia coefficient should satisfy:

[0094]

[0095] Where, ΔP max is the maximum power disturbance, J min is the minimum value that the inertia can take;

[0096] Step S104 : constructing a virtual synchronous control strategy for coordinating and optimizing inertia and damping by the damping ratio according to the adjustment coefficient within the selected range.

[0097] In this step, inertia and damping can be linked through the damping ratio. In a second-order time-domain system, different damping ratios have different transient response performances. Therefore, by adjusting the damping ratio, the damping can be adjusted in real time according to the inertia, thereby improving the power transient response of the system, and the following is obtained:

[0098]

[0099] Where D is the damping coefficient, J is the virtual inertia, ω0 is the rated angular frequency, K p is the primary frequency modulation coefficient, and K is the synchronization coefficient.

[0100] Criteria for setting the damping ratio:

[0101] In a constant damping ratio system, it is usually set to the optimal damping ratio To obtain a good transient response. This paper comprehensively considers the system response speed and overshoot. In the early stage of power disturbance, the system damping chooses underdamping to achieve a shorter adjustment time. In the later stage of power disturbance suppression, critical damping or overdamping should be selected to quickly suppress power oscillation and reduce power overshoot. At the same time, in order to ensure stable operation of the system and maintain appropriate dynamic performance, the system phase margin is set to >30°, that is:

[0102]

[0103] That is, ξ>0.2981.

[0104] According to the above design criteria, the adaptive damping ratio control strategy is designed as follows:

[0105]

[0106] Where ξ is the damping ratio, ξ1 is the set early transient damping ratio, which is used to speed up the early response of the system, ξ0 is the set steady-state damping ratio, ξ2 is the set late transient damping ratio, which is used to suppress the late overshoot of the power step response, Δω is the transient value of the angular frequency, T d is the set angular frequency deviation margin, and ΔP is the deviation between the reference active power and the virtual active output power.

[0107] Therefore, the overall damping ratio coordinated damping selection strategy is as follows: Figure 5 As shown in FIG, by detecting Δω and ΔP to obtain the frequency deviation and Δω*ΔP, and then selecting the damping ratio and inertia adjustment coefficient of the corresponding stage, the design transient damping selection strategy can be obtained.

[0108] In summary, the method of the present application analyzes the relationship between the deviation between active power and virtual active output power and the frequency differential, and uses it to replace the frequency deviation to realize continuous adjustment of inertia, avoid the introduction of differential signals, and reduce the introduction of high-frequency noise; by setting the inertia adjustment coefficient selection principle, on the one hand, the adjustment range of inertia is increased, which can better suppress the frequency deviation and frequency change rate, and on the other hand, it avoids frequency instability caused by too low inertia, thereby enhancing the stability of the power system; a damping ratio coordination strategy is designed, and the selection of damping can reduce overshoot and reduce the number of energy storage charges and discharges, while reducing the adjustment time, speeding up the speed at which power and frequency enter stability, and enhancing stability; and a steady-state frequency deviation algorithm for the power grid is designed to prevent the steady-state frequency deviation of the power grid from causing the transient damping algorithm to be mistakenly triggered, and mistakenly attributed to the frequency difference caused by the power difference, which in turn causes the damping to switch back and forth, and ultimately causes steady-state power oscillation.

[0109] See also Figure 6 , which shows a structural block diagram of a virtual synchronous control system of the present application for coordinating inertia and damping with a damping ratio.

[0110] like Figure 6 As shown, the virtual synchronous control system 200 includes a first building module 210 , a setting module 220 , a determination module 230 and a second building module 240 .

[0111] The first building module 210 is configured to build a grid-connected small signal model based on virtual synchronous machine control;

[0112] A setting module 220 is configured to set an inertia selection rule according to a power angle curve of the synchronous machine in the grid-connected small signal model;

[0113] A determination module 230 is configured to determine a selection range of inertia and an adjustment coefficient according to the inertia selection rule;

[0114] The second building module 240 is configured to build a virtual synchronous control strategy for coordinating and optimizing inertia and damping by the damping ratio according to the adjustment coefficient within the selected range. The expression of the damping ratio is:

[0115]

[0116] Where ξ is the damping ratio, ξ1 is the set early transient damping ratio, which is used to speed up the early response of the system, ξ0 is the set steady-state damping ratio, ξ2 is the set late transient damping ratio, which is used to suppress the late overshoot of the power step response, Δω is the transient value of the angular frequency, T d is the set angular frequency deviation margin, and AP is the deviation between the reference active power and the virtual active output power.

[0117] It should be understood that Figure 6Modules and references documented in Figure 1 Therefore, the operations and features described above for the method and the corresponding technical effects also apply to Figure 6 The modules in it will not be described in detail here.

[0118] In other embodiments, embodiments of the present invention further provide a computer-readable storage medium having a computer program stored thereon, wherein when the program instructions are executed by a processor, the processor is caused to execute the virtual synchronous control method of the damping ratio coordinated inertia and damping in any of the above method embodiments;

[0119] As an embodiment, the computer-readable storage medium of the present invention stores computer-executable instructions, and the computer-executable instructions are configured as follows:

[0120] Construct a grid-connected small signal model based on virtual synchronous machine control;

[0121] Setting an inertia selection rule according to the power angle curve of the synchronous machine in the grid-connected small signal model;

[0122] Determine the selection range of inertia and the adjustment coefficient according to the inertia selection rule;

[0123] Within the selected range, a virtual synchronous control strategy for coordinating and optimizing inertia and damping by the damping ratio is constructed according to the adjustment coefficient.

[0124] The computer-readable storage medium may include a program storage area and a data storage area, wherein the program storage area may store an operating system and application programs required for at least one function; the data storage area may store data created based on the use of the virtual synchronous control system for coordinating inertia and damping with a damping ratio, etc. In addition, the computer-readable storage medium may include a high-speed random access memory, and may also include a memory, such as at least one disk storage device, a flash memory device, or other non-volatile solid-state storage device. In some embodiments, the computer-readable storage medium may optionally include a memory remotely located relative to the processor, and these remote memories may be connected to the virtual synchronous control system for coordinating inertia and damping with a damping ratio via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0125] Figure 7 Schematic diagram of the structure of an electronic device provided by an embodiment of the present invention. Figure 7 As shown, the device includes: a processor 310 and a memory 320. The electronic device may also include: an input device 330 and an output device 340. The processor 310, the memory 320, the input device 330 and the output device 340 may be connected via a bus or other means. Figure 7The example of the bus connection is taken as an example. The memory 320 is the computer-readable storage medium mentioned above. The processor 310 executes various functional applications and data processing of the server by running the non-volatile software programs, instructions and modules stored in the memory 320, that is, realizes the virtual synchronous control method of the damping ratio coordinated inertia and damping in the above method embodiment. The input device 330 can receive input digital or character information, and generate key signal input related to user settings and function control of the virtual synchronous control system of the damping ratio coordinated inertia and damping. The output device 340 may include a display device such as a display screen.

[0126] The electronic device can execute the method provided by the embodiment of the present invention, and has the functional modules and beneficial effects corresponding to the execution method. For technical details not fully described in this embodiment, please refer to the method provided by the embodiment of the present invention.

[0127] As an embodiment, the electronic device is applied to a virtual synchronous control system for coordinating inertia and damping with a damping ratio, and is used on a client, and includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to:

[0128] Construct a grid-connected small signal model based on virtual synchronous machine control;

[0129] Setting an inertia selection rule according to the power angle curve of the synchronous machine in the grid-connected small signal model;

[0130] Determine the selection range of inertia and the adjustment coefficient according to the inertia selection rule;

[0131] Within the selected range, a virtual synchronous control strategy for coordinating and optimizing inertia and damping by the damping ratio is constructed according to the adjustment coefficient.

[0132] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus the necessary general hardware platform, or of course, by hardware. Based on this understanding, the essence of the above technical solution or the part that contributes to the existing technology can be embodied in the form of a software product. The computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a magnetic disk, an optical disk, etc., and includes a number of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods of each embodiment or certain parts of the embodiment.

[0133] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A virtual synchronous inertia and damping coordinated control method and system based on damping ratio, characterized in that: include: Construct a grid-connected small signal model based on virtual synchronous machine control; Setting an inertia selection rule according to a power angle curve of the synchronous machine in the grid-connected small signal model; Determine the selection range and adjustment coefficient of inertia according to the inertia selection rule; Within the selected range, a virtual synchronous control strategy for coordinating and optimizing inertia and damping by damping ratio is constructed according to the adjustment coefficient, and the expression of the damping ratio is: Where ξ is the damping ratio, ξ1 is the set early transient damping ratio, which is used to speed up the early response of the system, ξ0 is the set steady-state damping ratio, ξ2 is the set late transient damping ratio, which is used to suppress the late overshoot of the power step response, Δω is the transient value of the angular frequency, T d is the set angular frequency deviation margin, and ΔP is the deviation between the reference active power and the virtual active output power.

2. A virtual synchronous control method for coordinating inertia and damping with a damping ratio according to claim 1, characterized in that: in, The expression of the grid-connected small signal model is: Where J is the virtual inertia, ω0 is the rated angular frequency, D is the damping coefficient, s is the frequency domain factor, Δω(s) is the angular frequency disturbance, and ΔP ref (s) is the active reference disturbance, ΔP e (s) is the active electromagnetic power disturbance, ΔE(s) is the output voltage amplitude disturbance, K s is the reactive loop integral coefficient, K q is the reactive voltage regulation coefficient, ΔQ ref (s) is the reactive reference disturbance, ΔQ e (s) is the reactive electromagnetic power disturbance, Δθ(s) is the power angle disturbance, E is the output voltage amplitude, U g is the grid voltage amplitude, θ is the power angle, X d is the equivalent output reactance.

3. The virtual synchronous inertia and damping coordinated control method and system based on damping ratio according to claim 1 is characterized in that: The expression of the inertia selection rule is: J=J0+k1ΔPΔω, Where J is the virtual inertia, J0 is the initial inertia coefficient, k1 is the inertia adjustment coefficient, which is always a positive value, ΔP is the deviation between the reference active power and the virtual active output power, and Δω is the deviation between the output frequency and the rated frequency.

4. A virtual synchronous control method for coordinating inertia and damping with a damping ratio according to claim 1, characterized in that: Determining the selection range and adjustment coefficient of inertia according to the inertia selection rule includes: According to the dynamic constraints of the energy storage system and the dynamic frequency change rate of the energy storage system on the virtual synchronous control, the maximum inertia J is determined max and minimum inertia J min , and according to the maximum inertia J max and minimum inertia J min As well as the constraints of energy storage system stability, the selection range of inertia adjustment coefficient k1 is obtained, and the expression is: Where J0 is the initial inertia coefficient, k max is the maximum value of the inertia adjustment coefficient, D d is the equivalent damping value after the primary frequency modulation coefficient is equivalent to the damping coefficient, ω0 is the rated angular frequency, is the square of the maximum difference between the power command value and the actual output power, Set the selection principle of the inertia adjustment coefficient, and adjust the selection range of the inertia according to the selection principle of the inertia adjustment coefficient. The expression of the selection principle of the inertia adjustment coefficient is: In the formula, k J1 is the negative inertia zone adjustment coefficient, k J2 is the positive inertia adjustment coefficient, ΔP is the deviation between the reference active power and the virtual active output power, and Δω is the deviation between the output frequency and the rated frequency.

5. The virtual synchronous control method of the damping ratio coordinated inertia and damping according to claim 1 is characterized in that: in, The relationship between inertia and damping is established through the damping ratio, and the expression is: Where D is the damping coefficient, J is the virtual inertia, ω0 is the rated angular frequency, K p is the primary frequency modulation coefficient, and K is the synchronization coefficient.

6. A virtual synchronous inertia and damping coordinated control method and system based on damping ratio, characterized in that: include: A first building module is configured to build a grid-connected small signal model based on virtual synchronous machine control; A setting module configured to set an inertia selection rule according to a power angle curve of the synchronous machine in the grid-connected small signal model; A determination module, configured to determine a selection range and an adjustment coefficient of inertia according to the inertia selection rule; The second building module is configured to build a virtual synchronous control strategy for coordinating and optimizing inertia and damping of the damping ratio according to the adjustment coefficient within the selected range, and the expression of the damping ratio is: Where ξ is the damping ratio, ξ1 is the set early transient damping ratio, which is used to speed up the early response of the system, ξ0 is the set steady-state damping ratio, ξ2 is the set late transient damping ratio, which is used to suppress the late overshoot of the power step response, Δω is the transient value of the angular frequency, T d is the set angular frequency deviation margin, and ΔP is the deviation between the reference active power and the virtual active output power.

7. An electronic device, characterized in that: include: At least one processor, and a memory communicatively connected to the at least one processor, wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the method described in any one of claims 1 to 5.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the method according to any one of claims 1 to 5 is implemented.

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