Hybrid synchronous control method and system considering transient stability and network support

Abstract

The present application belongs to the technical field of grid-forming converter control, in order to solve the problem that the existing control strategy is difficult to balance the transient stability and grid support capability, a hybrid synchronization control method and system considering transient stability and grid support are proposed, when the grid-forming converter is detected to have transient instability risk, a grid-following control branch based on a first-order phase-locked loop is introduced in parallel on the basis of the original grid-forming virtual synchronous machine control loop; in the initial stage of the fault, by adjusting the gain proportional coefficient, the equivalent active power reference value is reduced to zero, so as to block the active power injection and minimize the acceleration area; after a preset initial time period, by dynamic adjustment, the equivalent active power reference value tracks the current electromagnetic power in real time, while continuing to suppress the power angle oscillation, the grid support capability of the converter is effectively restored.

Description

Technical Field

[0001] This invention belongs to the technical field of grid-type converter control, and particularly relates to a hybrid synchronous control method and system that takes into account both transient stability and grid support. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] With the continuous increase in the penetration rate of new energy sources and the large-scale integration of power electronic equipment, new power systems are increasingly exhibiting significant characteristics of low inertia and weak grids, posing severe challenges to the safe and stable operation of the system. To address this challenge, grid-based control strategies have received widespread attention. Grid-based converters, operating as voltage sources, can simulate the operating characteristics of traditional synchronous generators, actively constructing and maintaining the amplitude and phase of the terminal voltage, thereby providing the necessary voltage and frequency support for the system and effectively enhancing grid strength.

[0004] While grid-connected converters offer significant advantages in weak grid conditions, ensuring their transient synchronization stability remains a challenge when facing large grid disturbances. When severe faults such as voltage dips or phase jumps occur in the grid, the active power transmitted by the converter to the grid decreases significantly, leading to a severe imbalance between the active power reference value and the actual output power. This power imbalance can cause violent oscillations or monotonic divergence of the power angle within the converter. Once the power angle crosses the unstable equilibrium point, the system will lose synchronization; furthermore, under extremely weak grid conditions or severe fault conditions, the system's stable equilibrium point may even disappear entirely, ultimately causing the converter to disconnect from the grid.

[0005] To address the transient instability problem under large disturbances, existing improved control strategies mostly focus on maintaining synchronous stability during the transient period. For example, they suppress power angle divergence and improve the system's transient stability margin through parameter optimization, increasing transient damping, or switching synchronous control mechanisms during faults. However, in maintaining transient stability, existing technologies often come at the cost of severely limiting the converter's active power output and fault current injection, neglecting the need to maintain grid support performance during the transient period. This makes it difficult for existing control strategies to balance transient synchronous stability and grid support capabilities, resulting in a significant contradiction between the two. Summary of the Invention

[0006] To overcome the shortcomings of the prior art, this invention provides a hybrid synchronous control method and system that takes into account both transient stability and grid support. While effectively suppressing power angle divergence and improving system transient stability, it significantly enhances the grid support capability during faults, thus achieving an effective unification of transient synchronous stability and grid support capability.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] In a first aspect, the present invention provides a hybrid synchronization control method that balances transient stability and network support, comprising:

[0009] When a transient instability risk is detected in the grid-type converter, a grid-following control branch based on a first-order phase-locked loop is introduced in parallel on the basis of the original grid-type virtual synchronous machine control loop. The final output phase reference value of the grid-type converter is determined by the angular frequency deviation signal output by the grid-type control branch and the grid-following control branch.

[0010] Based on the instability detection time, the gain ratio coefficients of the network control branch and the network control branch are coordinated and controlled in stages. In the initial period after the fault is triggered, the equivalent active power reference value is reduced to zero by adjusting the gain ratio coefficient. After the preset initial period, the equivalent active power reference value is dynamically adjusted to track the current electromagnetic power in real time.

[0011] Secondly, the present invention provides a hybrid synchronization control system that balances transient stability and network support, comprising:

[0012] The construction module is configured to: when a transient instability risk is detected in the grid-type converter, a grid-following control branch based on a first-order phase-locked loop is introduced in parallel on the basis of the original grid-type virtual synchronous machine control loop. The final output phase reference value of the grid-type converter is determined by the angular frequency deviation signal output by the grid-type control branch and the grid-following control branch.

[0013] The control module is configured to: use the instability detection time as a reference to perform phased coordinated control of the gain ratio coefficients of the network control branch and the network-following control branch; during the initial time period after the fault is triggered, the equivalent active power reference value is reduced to zero by adjusting the gain ratio coefficient; after the preset initial time period, the equivalent active power reference value is dynamically adjusted to track the current electromagnetic power in real time.

[0014] Thirdly, the present invention provides an electronic device including a memory and a processor, and computer instructions stored in the memory and running on the processor, wherein the computer instructions, when executed by the processor, perform the method described in the first aspect.

[0015] Fourthly, the present invention provides a computer-readable storage medium for storing computer instructions, which, when executed by a processor, perform the method described in the first aspect.

[0016] The above one or more technical solutions have the following beneficial effects:

[0017] In this invention, when a transient instability risk is detected in a grid-type converter, a grid-following control branch based on a first-order phase-locked loop is introduced in parallel on the original grid-type virtual synchronous machine control loop. In the early stage of the fault, the equivalent active power reference value is reduced to zero by adjusting the gain ratio coefficient, thereby blocking active power injection and minimizing the acceleration area. After a preset initial time period, the equivalent active power reference value is dynamically adjusted to track the current electromagnetic power in real time, effectively restoring the grid support capability of the converter while continuing to suppress the power angle oscillation.

[0018] Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0019] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0020] Figure 1 Block diagram of adaptive hybrid synchronous control strategy for grid-type converters;

[0021] Figure 2 The equivalent Thevenin circuit for grid-connected converters. Detailed Implementation

[0022] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0023] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations of the present invention.

[0024] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0025] Example 1

[0026] This embodiment discloses a hybrid synchronization control method that balances transient stability and network support, including:

[0027] When a transient instability risk is detected in the grid-type converter, a grid-following control branch based on a first-order phase-locked loop is introduced in parallel on the basis of the original grid-type virtual synchronous machine control loop. The final output phase reference value of the grid-type converter is determined by the angular frequency deviation signal output by the grid-type control branch and the grid-following control branch.

[0028] Based on the instability detection time, the gain ratio coefficients of the network control branch and the network control branch are coordinated and controlled in stages. In the initial period after the fault is triggered, the equivalent active power reference value is reduced to zero by adjusting the gain ratio coefficient. After the preset initial period, the equivalent active power reference value is dynamically adjusted to track the current electromagnetic power in real time.

[0029] This embodiment proposes an adaptive hybrid synchronous control method for grid-connected converters that balances transient stability and grid support. First, upon detecting transient instability risk, a grid-following control branch based on a first-order phase-locked loop is introduced in parallel to the existing grid-connected virtual synchronous machine control loop, constructing a hybrid synchronous control architecture. Second, the physical mechanism by which the grid-following branch improves the system's equivalent active power reference value, equivalent damping, and equivalent inertia is clarified. Finally, based on the above mechanisms, the gain of the grid-connected control branch and the gain ratio of the two branches are coordinated and tuned in stages. In the early stages of a fault, the control strategy prioritizes establishing a new stable equilibrium point to quickly suppress power angle divergence; subsequently, it tracks electromagnetic power to maximize the recovery of active power output and the injection of fault short-circuit current. This embodiment effectively suppresses power angle divergence and improves system transient stability while significantly enhancing grid support capabilities during faults, achieving an effective balance between the two.

[0030] I. Constructing an adaptive hybrid synchronous control architecture for grid-type converters.

[0031] This step proposes an adaptive hybrid synchronous control strategy. When a transient instability risk is detected in the grid-connected converter, a grid-connected control branch based on a first-order phase-locked loop is introduced in parallel with the existing virtual synchronous machine active power control loop. The control architecture is as follows: Figure 1 As shown.

[0032] When the system is operating normally in grid-connected mode and no transient instability risk is detected, the grid-connected control branch is not activated, and the gain coefficient of the grid-connected control branch remains at its rated value. At this time, the system's active-frequency link maintains its original control, and its control equation is:

[0033] (1)

[0034] In the formula: P ref and P e These are the active power reference value and the electromagnetic power, respectively. T p This is the virtual inertial time constant; D p δ is the damping coefficient; δ′ is the angular velocity deviation value of the grid-type converter; Let be the first derivative of δ′.

[0035] At this point, the grid-connected control branch is not activated, and the gain coefficient of the grid-connected control branch remains at its rated value. In this state, the grid-connected converter operates as a voltage source, actively constructing phase using a virtual synchronous machine to provide the necessary voltage and frequency support to the grid. When the system encounters severe voltage drops or phase jumps and detects a risk of transient instability, the grid-connected control branch based on a first-order phase-locked loop is activated and operates in parallel with the original grid-connected control branch. Under this hybrid synchronous control architecture, the final output phase reference value of the converter is obtained by weighted summation and integration of the angular frequency deviation signals output by the two branches.

[0036] (2)

[0037] In the formula, i ref This serves as the final output phase reference value; oh 0 represents the rated angular frequency of the power grid; oh pll The angular frequency deviation signal output by the grid-type control branch is used to characterize the tracking characteristics of the grid phase. oh vsg The angular frequency deviation signal output by the network-type control branch is used to characterize the inertia and damping support characteristics; s is a complex frequency variable.

[0038] The specific formula for calculating the angular frequency deviation signal between the two branches is as follows:

[0039] (3)

[0040] (4)

[0041] In the formula, V t and i t These represent the voltage amplitude and phase at the converter's grid connection point, respectively. k pll The speed of grid phase synchronization is determined by the gain of the control branch in relation to the grid type. k vsg The gain of the network-type control branch is used to adjust the control weights of the virtual synchronous machine loop; T p This is the virtual inertial time constant; D p The damping coefficient; P ref and P e These are the active power reference value and the electromagnetic power, respectively.

[0042] To quantify and coordinate the interaction between the two control branches, a gain scaling factor is defined. m =k pll / k vsg During the transient period, through coordinated regulation k pll and k vsg It can reshape the active power and frequency response characteristics of the converter under large disturbances, thereby suppressing power angle divergence while retaining the grid support capability of the grid-type converter.

[0043] II. Coordinated adjustment mechanism of gain parameters between the network and the structure network.

[0044] First, establish the equivalent circuit of the grid-connected converter and the power grid, such as... Figure 2 As shown: E eref This refers to the internal potential amplitude of the grid-type converter; X eq The equivalent output reactance of the converter; U g The voltage amplitude of an infinitely large power grid; X i The equivalent reactance of the grid-type converter to the outside; X o The equivalent grid reactance is determined by the transformer leakage reactance. X t Reactance of power grid lines X g It is connected in series.

[0045] Combining the power transmission relationship of the equivalent circuit above, and substituting the angular frequency deviation signal and the circuit relationship at the grid connection point under the hybrid synchronous control architecture into the virtual rotor motion equation, the equivalent swing equation of the grid-type converter under this strategy can be derived:

[0046] (5)

[0047] Among them, the equivalent active power reference value P refeq The expression is:

[0048] (6)

[0049] In the formula, P ref and P e These are the active power reference value and the electromagnetic power, respectively. d Generate phase deviation values ​​for the converter; D p The damping coefficient; V t This refers to the voltage amplitude at the converter's grid connection point. dt The voltage phase deviation at the grid connection point is denoted as ; m is the gain ratio coefficient. D peq This is the equivalent damping coefficient; T peq It is the equivalent virtual inertial time constant.

[0050] Therefore, by introducing a grid-type control branch, and through the gain ratio coefficient... m A negative feedback term proportional to the power angle deviation was added. When a large disturbance in the power grid limits the converter's output power, this negative feedback term ensures that the equivalent active power reference value... P refeq Lower than the original reference active power value P ref This mechanism effectively reduces the transient energy injected into the system during faults, alleviates the accelerating effect of unbalanced active power on the virtual rotor, and prevents monotonically divergent instability of the power angle.

[0051] Meanwhile, the equivalent damping coefficient D peq The expression is:

[0052] (7)

[0053] (8)

[0054] In the formula, D p The damping coefficient; k vsg To control the gain of the network-type control branch; k 0 represents the additional damping term introduced by the first-order phase-locked loop; m is the gain proportionality coefficient. T p This is the virtual inertial time constant; V t Voltage amplitude at the converter grid connection point; d t This refers to the phase deviation value of the voltage at the grid connection point. X o The equivalent grid reactance is determined by the transformer leakage reactance. X t Reactance of power grid lines X g Composed of series connection; X eq The equivalent output reactance of the converter; k vsg For network gain; This represents the magnitude of the internal potential of the converter.

[0055] Total damping of the system under hybrid synchronous control Dpeq Includes network-type control branch gain k vsg The inherent damping amplification effect caused by the reduction, as well as the additional damping term provided by the network branches. k 0. The synergistic effect of these two factors significantly increases the total damping of the system, effectively accelerating the dissipation of transient energy during faults, thereby significantly suppressing the violent oscillation of the power angle. Furthermore, the equivalent virtual inertial time constant... T peq The expression is:

[0056] (9)

[0057] in, T p This is the virtual inertial time constant; k vsg To control the gain of the network-type control branch.

[0058] Equivalent virtual inertia and networked control branch gain k vsg Inversely proportional, by actively reducing the gain of the network-type control branch. k vsg This allows the converter to achieve much higher performance than... T p The equivalent inertia significantly enhances the system's energy buffering capacity in the early stages of a fault and substantially extends the critical clearing time. After fault clearing, the gain of the network-type control branch is restored. k vsg This can reduce the equivalent inertia and accelerate the convergence of the work angle.

[0059] When a transient instability risk is detected and hybrid synchronous control is triggered, the gain of the network-type control branch needs to be adjusted. k vsg With gain scaling factor m Perform coordinated tuning. Significantly reduce the gain of the network-type control branches. k vsg During the transient control period, the equivalent damping term dominates the overall system damping. Substituting the equivalent damping and equivalent inertia at this time into the work angle closed-loop transfer function, the equivalent system damping ratio can be derived. g The expression is:

[0060] (10)

[0061] In the formula, D p The damping coefficient; k vsg For network gain; T p This is the virtual inertial time constant; Xeq The equivalent output reactance of the converter; U g This represents the voltage amplitude of an infinitely large power grid.

[0062] To quantify the stability improvement capability after a fault, and to prevent the system from entering an overdamped state and weakening the active power support capability, a critical damping enhancement coefficient is introduced. n .like n If the value is too large, the closed-loop system will exhibit severe overdamping characteristics, leading to a significant decrease in the active power output support response speed of the converter; if the value is too small, it will not provide sufficient transient stability margin. Its value can be defined as the transient damping ratio. g th Optimal damping ratio under steady-state design g op The ratio, that is:

[0063] (11)

[0064] This leads to the deduction of the fault period k vsg The value is:

[0065] (12)

[0066] in, D p The damping coefficient; T p This is the virtual inertial time constant; X eq The equivalent output reactance of the converter; U g The voltage amplitude of an infinitely large power grid; n This is the critical damping enhancement coefficient; g op The optimal damping ratio for steady-state design.

[0067] To maximize the recovery of grid support capacity while suppressing power angle divergence, the instability detection time is... t fault Based on, for m A phased coordinated control approach is adopted. During the initial time period Δ after a fault is triggered... t within (i.e. t < t fault + Δ t The system faces an extremely high risk of initial swing instability. To quickly suppress the monotonic divergence of the work angle, the control objective prioritizes establishing a new stable equilibrium point by tuning the critical damping enhancement coefficient. mThis reduces the equivalent active power reference value to zero, thereby blocking active power injection and minimizing the acceleration area. The gain scaling factor value during this stage is... m stable The is:

[0068] (13)

[0069] in, D p The damping coefficient; V t Voltage amplitude at the converter grid connection point; d t This refers to the phase deviation value of the voltage at the grid connection point. P ref This is a reference value for active power. d Generate phase deviation values ​​for the converter.

[0070] After the preset initial time period (i.e.) t ≥ t fault + Δ t If the zero-power injection state is maintained, it will excessively limit the active power support and fault current output that the converter can provide to the grid. Therefore, it is necessary to dynamically adjust the equivalent active power reference value to track the current electromagnetic power in real time. This adjustment mechanism effectively restores the converter's grid support capability while continuing to smooth out power angle oscillations. At this time, the gain ratio coefficient value... m GFM for:

[0071] (14)

[0072] in, P ref and P e These are the active power reference value and the electromagnetic power, respectively. D p The damping coefficient; V t This refers to the voltage amplitude at the converter's grid connection point. d t This refers to the phase deviation value of the voltage at the grid connection point. d Generate phase deviation values ​​for the converter.

[0073] In this implementation scheme, during the initial stage of a fault, the control strategy prioritizes establishing a new stable equilibrium point to quickly suppress power angle divergence; subsequently, it tracks electromagnetic power to maximize the recovery of active power output and the injection of fault short-circuit current. This invention effectively suppresses power angle divergence and improves system transient stability while significantly enhancing the grid's support capability during faults, achieving an effective balance between the two.

[0074] Example 2

[0075] The purpose of this embodiment is to provide a hybrid synchronous control system that balances transient stability and network support, including:

[0076] The construction module is configured to: when a transient instability risk is detected in the grid-type converter, a grid-following control branch based on a first-order phase-locked loop is introduced in parallel on the basis of the original grid-type virtual synchronous machine control loop. The final output phase reference value of the grid-type converter is determined by the angular frequency deviation signal output by the grid-type control branch and the grid-following control branch.

[0077] The control module is configured to: use the instability detection time as a reference to perform phased coordinated control of the gain ratio coefficients of the network control branch and the network-following control branch; during the initial time period after the fault is triggered, the equivalent active power reference value is reduced to zero by adjusting the gain ratio coefficient; after the preset initial time period, the equivalent active power reference value is dynamically adjusted to track the current electromagnetic power in real time.

[0078] In further embodiments, the following is also provided:

[0079] An electronic device includes a memory and a processor, as well as computer instructions stored in the memory and running on the processor. When executed by the processor, the computer instructions perform the method described in Embodiment 1. For brevity, further details are omitted here.

[0080] It should be understood that in this embodiment, the processor can be a central processing unit (CPU), or it can be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or any conventional processor, etc.

[0081] Memory may include read-only memory and random access memory, and provides instructions and data to the processor. A portion of memory may also include non-volatile random access memory. For example, memory may also store information about the device type.

[0082] A computer-readable storage medium for storing computer instructions, which, when executed by a processor, perform the method described in Embodiment 1.

[0083] The method in Embodiment 1 can be directly implemented by a hardware processor, or implemented by a combination of hardware and software modules within the processor. The software modules can reside in readily available storage media in the art, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, or registers. This storage medium is located in memory; the processor reads information from the memory and, in conjunction with its hardware, completes the steps of the above method. To avoid repetition, a detailed description is not provided here.

[0084] A computer program product includes a computer program that, when executed by a processor, implements the method described in Embodiment 1.

[0085] The present invention also provides at least one computer program product tangibly stored on a non-transitory computer-readable storage medium. The computer program product includes computer-executable instructions, such as instructions included in program modules, which execute in a device on a target real or virtual processor to perform the processes / methods described above. Typically, program modules include routines, programs, libraries, objects, classes, components, data structures, etc., that perform specific tasks or implement specific abstract data types. In various embodiments, the functionality of program modules can be combined or divided among program modules as needed. The machine-executable instructions for the program modules can execute within a local or distributed device. In a distributed device, the program modules can reside in both local and remote storage media.

[0086] The computer program code used to implement the methods of the present invention may be written in one or more programming languages. This computer program code may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when executed by the computer or other programmable data processing device, the program code causes the functions / operations specified in the flowcharts and / or block diagrams to be implemented. The program code may be executed entirely on a computer, partially on a computer, as a stand-alone software package, partially on a computer and partially on a remote computer, or entirely on a remote computer or server.

[0087] In the context of this invention, computer program code or related data may be carried by any suitable carrier to enable a device, apparatus, or processor to perform the various processes and operations described above. Examples of carriers include signals, computer-readable media, and the like. Examples of signals may include electrical, optical, radio, sound, or other forms of propagation signals, such as carrier waves, infrared signals, etc.

[0088] Those skilled in the art will recognize that the units and algorithm steps described in conjunction with the embodiments herein can be implemented in electronic hardware or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0089] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A hybrid synchronous control method that balances transient stability and network support, characterized in that, include: When a transient instability risk is detected in the grid-type converter, a grid-following control branch based on a first-order phase-locked loop is introduced in parallel on the basis of the original grid-type virtual synchronous machine control loop. The final output phase reference value of the grid-type converter is determined by the angular frequency deviation signal output by the grid-type control branch and the grid-following control branch. Based on the instability detection time, the gain ratio coefficients of the grid-forming control branch and the grid-following control branch are coordinated and controlled in stages. The gain ratio coefficient is the ratio of the gain of the grid-following control branch to the gain of the grid-forming control branch. In the initial time period after the fault is triggered, the equivalent active power reference value is reduced to zero by adjusting the gain ratio coefficient. After the preset initial time period, the equivalent active power reference value is dynamically adjusted to track the current electromagnetic power in real time. The determination of the gain of the network control branch during a fault is as follows: Once a transient instability risk is detected and hybrid synchronous control is triggered, the equivalent damping and equivalent inertia at this point are substituted into the power angle closed-loop transfer function to derive the equivalent system damping ratio. The expression for the equivalent damping ratio is as follows: In the formula, D p The damping coefficient; k vsg For network gain; T p This is the virtual inertial time constant; X eq The equivalent output reactance of the converter; U g The voltage amplitude of an infinitely large power grid; A critical damping enhancement coefficient is introduced, which is determined by the ratio of the transient damping ratio to the optimal damping ratio under steady-state design. The gain of the network control branch during a fault is determined based on the equivalent system damping ratio and the critical damping enhancement coefficient, specifically: in, D p The damping coefficient; X eq The equivalent output reactance of the converter; T p This is the virtual inertial time constant; U g The voltage amplitude of an infinitely large power grid; k vsg To control the gain of the network control branches; ζ op The optimal damping ratio under steady-state design; n This is the critical damping enhancement coefficient; This represents the amplitude of the internal potential of the converter.

2. The hybrid synchronous control method that balances transient stability and network support as described in claim 1, characterized in that, The final output phase reference value of the grid-type converter is determined by the angular frequency deviation signals output from the grid control branch and the grid-following control branch, specifically: in, θ ref This is the final output phase reference value for the grid-type converter; ω pll The angular frequency deviation signal output by the network control branch; ω vsg The angular frequency deviation signal output by the network control branch; ω 0 represents the rated angular frequency of the power grid; k pll To control the gain of the branch circuit; k vsg To control the gain of the network control branches; V t and θ t These represent the voltage amplitude and phase at the converter's grid connection point, respectively. T p This is the virtual inertial time constant; D p The damping coefficient; P ref and P e These are the active power reference value and the electromagnetic power, respectively; s is the complex frequency variable.

3. The hybrid synchronous control method that balances transient stability and network support as described in claim 1, characterized in that, By constructing an equivalent circuit between the grid-connected converter and the power grid, and based on the power transmission relationship of the equivalent circuit, the angular frequency deviation signal under the hybrid synchronous control architecture of the grid-connected control branch and the grid-connected point is substituted into the virtual rotor motion equation to derive the equivalent swing equation of the grid-connected converter, thereby determining the equivalent active power reference value; the equivalent active power reference value is less than the original reference active power value.

4. The hybrid synchronous control method that balances transient stability and network support as described in claim 1, characterized in that, The critical damping enhancement coefficient is as follows: in, ζ th The transient damping ratio; ζ op The optimal damping ratio for steady-state design.

5. The hybrid synchronous control method that balances transient stability and network support as described in claim 1, characterized in that, During the initial period after a fault is triggered, the equivalent active power reference value is reduced to zero by adjusting the gain ratio coefficient. At this time, the gain ratio coefficient value... m stable for: in, P ref This is a reference value for active power. D p The damping coefficient; V t This refers to the voltage amplitude at the converter's grid connection point. δ t This refers to the phase deviation value of the voltage at the grid connection point. δ Generate phase deviation values ​​for the converter.

6. The hybrid synchronous control method that balances transient stability and network support as described in claim 1, characterized in that, After a preset initial time period, dynamic adjustments are made to ensure that the equivalent active power reference value tracks the current electromagnetic power in real time. At this time, the gain ratio coefficient value... m GFM for: in, P ref and P e These are the active power reference value and the electromagnetic power, respectively. D p The damping coefficient; V t This refers to the voltage amplitude at the converter's grid connection point. δ t This refers to the phase deviation value of the voltage at the grid connection point. δ Generate phase deviation values ​​for the converter.

7. A hybrid synchronous control system that balances transient stability and network support, characterized in that, include: The construction module is configured to: when a transient instability risk is detected in the grid-type converter, introduce a grid-following control branch based on a first-order phase-locked loop in parallel on the basis of the original grid-type virtual synchronous machine control loop, and determine the final output phase reference value of the grid-type converter by the angular frequency deviation signal output by the grid-type control branch and the grid-following control branch. The control module is configured to: coordinate and control the gain ratio coefficients of the network control branch and the network control branch in stages based on the instability detection time. The gain ratio coefficient is the ratio of the gain of the network control branch to the gain of the network control branch. In the initial time period after the fault is triggered, the equivalent active power reference value is reduced to zero by adjusting the gain ratio coefficient. After the preset initial time period, the equivalent active power reference value is dynamically adjusted to track the current electromagnetic power in real time. The determination of the gain of the network control branch during a fault is as follows: Once a transient instability risk is detected and hybrid synchronous control is triggered, the equivalent damping and equivalent inertia at this point are substituted into the power angle closed-loop transfer function to derive the equivalent system damping ratio. The expression for the equivalent damping ratio is as follows: In the formula, D p The damping coefficient; k vsg For network gain; T p This is the virtual inertial time constant; X eq This is the equivalent output reactance of the converter; U g The voltage amplitude of an infinitely large power grid; A critical damping enhancement coefficient is introduced, which is determined by the ratio of the transient damping ratio to the optimal damping ratio under steady-state design. The gain of the network control branch during a fault is determined based on the equivalent system damping ratio and the critical damping enhancement coefficient, specifically: in, D p The damping coefficient; X eq This is the equivalent output reactance of the converter; T p This is the virtual inertial time constant; U g The voltage amplitude of an infinitely large power grid; k vsg To control the gain of the network control branches; ζ op The optimal damping ratio under steady-state design; n This is the critical damping enhancement coefficient; This represents the amplitude of the internal potential of the converter.

8. An electronic device, characterized in that, It includes a memory and a processor, as well as computer instructions stored in the memory and running on the processor, which, when executed by the processor, perform the method according to any one of claims 1-6.

9. A computer-readable storage medium, characterized in that, Used to store computer instructions, which, when executed by a processor, perform the method described in any one of claims 1-6.

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