Hybrid energy storage converter coordinated control method for virtual power plant fault state

Abstract

The present application relates to the field of virtual power plant and micro-grid control, in particular to a hybrid energy storage converter collaborative control method for a virtual power plant fault state, the method comprising: constructing a virtual power plant island micro-grid system containing energy type and power type energy storage converters; taking each converter as an intelligent agent to build a sparse communication network; collecting each converter's own parameters and completing information interaction through the sparse communication network; constructing three types of fault adaptive collaborative control strategies for load mutation, communication interruption and hardware failure; inputting the active power reference instruction output by the control strategy into a VSG basic controller; converting the controller output modulation voltage into a three-phase alternating current waveform; and generating a PWM switching signal to drive an inverter bridge, thereby realizing grid voltage and frequency control. The present application can be directly applied to the distributed network type converter aggregated by the virtual power plant, and significantly improves the robustness and survivability of the system under multiple fault states such as communication interruption, load mutation and hardware failure.

Description

Technical Field

[0001] This invention relates to the field of virtual power plant and microgrid control, and in particular to a hybrid energy storage converter collaborative control method for virtual power plant fault conditions. Background Technology

[0002] Virtual power plants aggregate and coordinate distributed power sources, energy storage systems, and loads through communication and control technologies to participate in grid dispatch. Hybrid energy storage systems, combining the complementary advantages of energy-type and power-type energy storage, are key units for smoothing fluctuations and providing ancillary services. However, traditional hybrid energy storage control relies on a common DC bus, making it difficult to directly apply to distributed energy storage connected to AC microgrids via grid-forming converters (GFCs) in virtual power plants. Therefore, it is necessary to explore distributed hybrid energy storage methods that adapt to the flexible aggregation requirements of virtual power plants, starting with grid-forming converter control.

[0003] In the control of grid-connected converters, Virtual Synchronous Generator (VSG) control technology is widely used. It can simulate the characteristics of synchronous generators and provide inertia support. However, it has an inherent steady-state error problem and cannot directly meet the complex power distribution requirements of hybrid energy storage. To eliminate steady-state error and achieve precise power distribution, distributed secondary control based on multi-agent systems has gradually become the mainstream. It can achieve decentralized coordination with only sparse communication networks, which meets the requirements of virtual power plants for plug-and-play and flexible expansion.

[0004] However, the operating environment of virtual power plants is complex, and their aggregated energy storage devices often face fault states such as communication interruptions, sudden load changes, and hardware failures, posing a serious threat to the collaborative control that relies on underlying network interaction. During communication interruptions, consensus protocols fail, and there is a lack of degraded operation mechanisms for heterogeneous energy storage. During sudden load changes, the coupling between frequency recovery and power transfer processes can easily trigger reverse power regulation, which may be amplified into system-level fluctuations through aggregation effects. In the event of physical hardware failure, directly shutting down the communication module will lead to topology breaks, causing local or even global collaborative paralysis. Therefore, improving the resilience and fault tolerance of distributed hybrid energy storage converters under virtual power plant fault states is an urgent issue to be addressed. Summary of the Invention

[0005] To address the issues of collaborative failure due to communication interruptions, power reversal caused by sudden load changes, and topology paralysis due to physical power source faults in distributed hybrid energy storage systems aggregated in virtual power plants under fault conditions, this invention provides a collaborative control method for hybrid energy storage converters under virtual power plant fault conditions, comprising the following steps:

[0006] S1. Construct a virtual power plant islanded AC microgrid system containing energy-type and power-type energy storage converters, and build a sparse communication network with each converter as a node;

[0007] S2. Collect local electrical parameters of each converter to complete VSG basic control, and interact through a sparse communication network to achieve frequency synchronization and power distribution of multiple converters.

[0008] S3, which integrates three types of strategies: dynamic decoupling control, communication anomaly response, and power failure tolerance, to form a fault adaptive cooperative control strategy.

[0009] S4. Input the control commands output by the fault adaptive cooperative control strategy into the VSG basic controller of each converter.

[0010] The S5 and VSG basic controller output modulation voltage is converted by dq inverse transformation and SVPWM to generate drive signals, which are used to regulate the voltage and frequency of the virtual power plant islanded AC microgrid system.

[0011] Preferably, in step S1, the virtual power plant islanded AC microgrid system includes at least one energy-type energy storage converter and one power-type energy storage converter;

[0012] An isolated AC microgrid system also includes a DC power supply, an inverter, an LCL filter, a feeder impedance, and local loads. The DC power supply includes two types of energy storage units: batteries and supercapacitors.

[0013] In sparse communication networks, each converter is regarded as an intelligent node. If there is a communication connection between two intelligent nodes, they are neighbor nodes.

[0014] Preferably, in step S2, the local electrical parameters of each converter include output voltage, current, local active power, reactive power, voltage amplitude and frequency obtained by power calculation;

[0015] The active power reference value obtained by each converter after distributed collaborative computing is used as a consistency variable, and the consistency variable is interacted through a sparse network.

[0016] Preferably, in step S3, the dynamic decoupling control strategy is as follows: calculate the total power of the virtual power plant islanded AC microgrid system, and perform high-pass and low-pass filtering on the total power to obtain high-frequency and low-frequency components. Then, use a dynamic following algorithm based on actual power anchoring to generate active power reference commands for the power-type energy storage converter and the energy-type energy storage converter.

[0017] Preferably, the expressions for the high-frequency components and the low-frequency components are as follows: ;

[0018] in, , Relying on the first The low-frequency and high-frequency components of the total microgrid power calculated by each converter are then filtered. This is the adjustable time constant of the filtering stage. For complex variables, To rely on the first The total power of the global microgrid is obtained by distributed communication and interaction calculation of individual converters. This refers to the total number of energy storage converters. For the first Consistency variables for energy storage converters;

[0019] The active power reference command expression is: ;

[0020] in, , The first Active power reference commands for power-type energy storage converters and energy-type energy storage converters. , The first The actual output active power of power-type energy storage converters and energy-type energy storage converters. This represents the total number of power-type energy storage converters.

[0021] Preferably, in step S3, the communication anomaly handling strategy is as follows:

[0022] When any energy storage converter is completely disconnected from the communication network and its neighboring nodes are empty, state correction is performed solely based on the deviation between the actual local output power and the reference power, expressed as: ;

[0023] in, For the first One converter iteration Consistency variables at this time For the first One converter iteration Consistency variables at this time This is the deviation correction factor. This is the power control proportional coefficient. For the first The actual local output power of each converter It is the first Reference power of each converter;

[0024] When any power-type energy storage converter is completely disconnected from the communication network, its consistency variables remain unchanged: .

[0025] Preferably, in step S3, the power supply fault tolerance strategy is as follows: when any converter stops operating due to a physical hardware failure, an information relay reconfiguration mechanism is adopted to redefine the converter that has experienced a physical hardware failure as an information relay node.

[0026] Preferably, for a faulty converter, the local power deviation correction term in its secondary control law is removed, and the reconstructed control law retains only the neighbor information forwarding function, expressed as: ;

[0027] in, For the first One converter iteration Consistency variables at this time For the first One converter iteration Consistency variables at this time For multi-agent communication weight coefficients, For converter The sequence number of the neighboring node with which there is a communication connection. For converter The neighborhood set.

[0028] Preferably, in step S4, the VSG base controller integrates VSG control and voltage and current dual closed-loop control.

[0029] Preferably, step S5 specifically involves: the VSG basic controller outputting a modulation voltage command, which is converted into a three-phase AC voltage waveform through inverse dq coordinate transformation; the three-phase AC voltage waveform is then converted into a three-phase PWM switching control signal through space vector pulse width modulation; the three-phase PWM switching control signal is applied to the inverter bridge arm of the converter to realize the control of the voltage and frequency of the entire virtual power plant islanded AC microgrid system.

[0030] The beneficial effects of this invention are as follows:

[0031] This invention proposes a hybrid energy storage converter collaborative control method for virtual power plant fault states. This method does not require modification or addition of power equipment and can be directly applied to the distributed grid-type converters aggregated in the virtual power plant. It significantly improves the robustness and survivability of the system under various fault states such as communication interruption, load change and hardware failure.

[0032] This invention proposes a dynamic following decoupling algorithm based on actual power anchoring, which eliminates the problem of transient active power reverse regulation in traditional control from the root and successfully decouples frequency recovery from power transfer process, enabling the two to proceed independently according to their respective optimal time scales, greatly improving transient stability and effectively coping with fault scenarios such as load changes.

[0033] This invention proposes fault-tolerant mechanisms such as communication weight reconstruction, local autonomous degradation, and information relay reconstruction, which effectively overcome the high dependence of distributed collaborative control on the integrity of communication topology, realize all-round fault-tolerant operation from communication interruption to physical hardware damage, effectively cope with fault scenarios such as communication interruption and hardware failure, and ensure the basic energy management and power support capabilities of virtual power plants under fault conditions. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the overall process of an embodiment of the present invention;

[0035] Figure 2 This is a block diagram of the VSG control used in the energy storage converter in this embodiment of the invention;

[0036] Figure 3 This is the overall control block diagram of GFC (Geostationary Fiber Optic Complex) for isolated microgrids according to an embodiment of the present invention;

[0037] Figure 4 This is a comparison of communication weights before and after communication is disconnected in an islanded microgrid system according to an embodiment of the present invention;

[0038] Figure 5 This is a comparison of communication weights before and after a power failure in an islanded microgrid system according to an embodiment of the present invention. Detailed Implementation

[0039] Embodiments of the present invention provide a hybrid energy storage converter cooperative control method for virtual power plant fault states, such as... Figure 1 As shown, it includes the following steps:

[0040] S1. Construct a virtual power plant islanded AC microgrid system, which includes multiple grid-type converters. Each grid-type converter includes at least one energy storage converter and one power storage converter. Construct a sparse communication network for information exchange between the converters to form a multi-agent collaborative interaction system.

[0041] In sparse communication networks, each converter is regarded as an intelligent node. If there is a communication connection between two intelligent nodes, they are neighbor nodes.

[0042] Energy-type energy storage converters refer to grid-connected converters that use batteries to provide DC-side voltage, while power-type energy storage converters refer to grid-connected converters that use supercapacitors to provide DC-side voltage. Different types of converters employ different control strategies in subsequent control.

[0043] An isolated AC microgrid system also includes a DC power supply, an inverter, an LCL filter, a feeder impedance, and local loads. The DC power supply includes two types of energy storage units: batteries and supercapacitors.

[0044] like Figure 3 As shown, the system includes two converters connected to the AC bus via LCL filters. The converters exchange information through a sparse communication network and perform distributed secondary cooperative control. Figure 3 The left side of the diagram represents an energy-type energy storage converter (battery-powered), while the right side represents a power-type energy storage converter (supercapacitor-powered). The two converters employ different consistency protocols: one with local power deviation feedback and the other without. Each converter includes modules for power calculation, VSG control, transient virtual impedance control, and dual-loop voltage and current control. The power calculation module acquires local active and reactive power. VSG control provides inertia and primary frequency / voltage regulation functions. Transient virtual impedance control adjusts power distribution only during dynamic processes and automatically disables in steady state. The dual-loop voltage and current control ensures output waveform quality. Finally, SVPWM modulation converts commands into switching signals to drive the converter.

[0045] S2. Each converter collects its own output voltage and current through a local acquisition module, and obtains local active power, reactive power, voltage amplitude and frequency through power calculation, which are used for the VSG control of the grid-type converter itself. The active power reference value obtained by each converter after distributed collaborative calculation is used as a consistency variable. The consistency variable is sent to neighboring nodes through a sparse communication network, and the consistency variable uploaded by neighboring nodes is received at the same time to complete the distributed interaction of status information between multiple nodes, and realize frequency synchronization and power distribution among multiple converters.

[0046] S3. Construct a fault-adaptive collaborative control strategy that integrates three sub-strategies: dynamic decoupling control, communication anomaly response, and power fault tolerance. These strategies are designed to ensure stable system operation in response to fault conditions such as load surges, communication interruptions, or power failures faced by the virtual power plant.

[0047] Grid-type converter sampling VSG control strategy, such as Figure 2As shown, the VSG control consists of two parts: an active-frequency (Pf) control loop and a reactive-voltage (QV) control loop. The Pf loop generates frequency and phase angle commands based on active power deviation, virtual inertia, and damping coefficient. The QV loop generates voltage amplitude commands based on reactive power deviation and integral regulation. Both are output to the subsequent voltage and current dual-loop control system. The VSG control strategy enables the grid-type converter to simulate the motion equations and excitation regulation characteristics of a synchronous generator rotor, providing inertial support and damping characteristics for the converter, thereby ensuring the stable operation of the microgrid. Furthermore, the VSG control also mimics the power-sharing capability of a synchronous generator by executing frequency and voltage droop control.

[0048] The active frequency control equation for VSG is: ;

[0049] in, For rotational inertia, For output frequency, For the rated frequency, For GFC to output active power, The active power setpoint for VSG control. The damping coefficient is... This is the active power reference value for droop control. This is the droop factor for frequency-active power.

[0050] The reactive voltage control equation for VSG is: ;

[0051] in, The reactive power setpoint for VSG control. This is the reactive power reference value for droop control. For GFC reactive power output, Rated voltage, For measuring the output voltage of GFC, This is the voltage command value controlled by VSG. This is the voltage-reactive power droop factor. The integral coefficient is... Laplace transform complex frequency operator.

[0052] The power transmission of grid-connected converters using VSG control follows a droop characteristic, controlled and distributed under the influence of load and primary control. However, this control results in frequency deviation from the rated value. To eliminate steady-state frequency error and achieve high-precision power sharing among converters, a secondary control strategy must be introduced. Energy storage supports the grid frequency and shares all steady-state loads; its distributed secondary control law employs a consistency protocol with local active power deviation feedback, designed as follows: ;

[0053] in, For the first The converter is in the first Reference power at the next iteration For the first One converter iteration Consistency variables at this time For the first One converter iteration Consistency variables at this time This is the deviation correction factor. This is the power control proportional coefficient. For the first The actual local output power of each converter It is the first Reference power of each converter For multi-agent communication weight coefficients, For converter The sequence number of the neighboring node with which there is a communication connection. For converter The neighborhood set of, that is, with The set of all directly connected neighboring nodes.

[0054] Power-type energy storage is used to meet instantaneous load demands. To ensure that it does not output active power in steady state, its distributed secondary control law active power reference command is forcibly set to zero, and the local feedback loop is removed during the consistency iteration. The design is as follows: ;

[0055] in, It is the first The reference power of each converter.

[0056] The dynamic decoupling control strategy is as follows:

[0057] Traditional DC hybrid energy storage dynamic control relies on low-pass and high-pass filtering of the total system power to achieve power distribution. If it is directly applied to distributed AC microgrids, the target reference power will lag behind the actual power during sudden load changes, triggering reverse adjustment of active power.

[0058] This embodiment obtains the consistency variables of the energy-type energy storage converter through a sparse communication network, calculates the total power of the microgrid through multi-agent communication (each node interacts with the consistency variables through sparse communication, combined with the total number of converters), and performs high-pass and low-pass filtering on the total power to obtain high-frequency and low-frequency components. Using a dynamic following algorithm based on actual power anchoring, the reference power commands of the power-type energy storage converter and the energy-type energy storage converter are anchored to the target values ​​generated by the high-frequency and low-frequency filtered components of the total power of the microgrid, respectively. This is used to eliminate the phenomenon of reverse regulation of transient active power and to make the frequency recovery process and the hybrid energy storage power transfer process run independently.

[0059] The expressions for the low-frequency and high-frequency components are: ;

[0060] in, , Relying on the first The low-frequency and high-frequency components of the total microgrid power calculated by each converter are then filtered. The adjustable time constant of the filtering stage is used to control the dynamic speed of the hybrid energy storage power transfer process. For complex variables, To rely on the first The total power of the global microgrid is obtained by distributed communication and interaction calculation of individual converters. This refers to the total number of energy storage converters. For the first Consistency variables for energy storage converters;

[0061] Based on the dynamic following algorithm anchored to actual power, active power reference commands are generated for both power-type and energy-type energy storage converters, expressed as follows: ;

[0062] in, , The first Active power reference commands for power-type energy storage converters and energy-type energy storage converters. , The first The actual output active power of power-type energy storage converters and energy-type energy storage converters. This represents the total number of power-type energy storage converters.

[0063] The algorithm ensures that the converter's reference power is between the actual power and the final target power of the dynamic process, eliminating the phenomenon of reverse regulation of transient active power at the source, and enabling the frequency recovery process and the hybrid energy storage power transfer process to operate independently on their respective time scales.

[0064] The specific strategies for handling communication anomalies are as follows:

[0065] Distributed collaborative control is highly dependent on the reliability of the communication network. A local communication link failure will trigger topology mutations and cause conventional consensus protocols to fail. Therefore, this invention designs a communication anomaly handling strategy, implemented based on the communication weight reconstruction mechanism of a multi-agent collaborative interaction system and a local degradation control protocol, such as... Figure 4 As shown, when the local communication link is disconnected, each converter updates its neighborhood set in real time through local sensing. And combined with the preset multi-agent stability coefficient The communication topology weights are dynamically updated, and the control mode is switched to local autonomous mode when the node is completely offline, ensuring the basic operational capabilities of the underlying equipment of the virtual power plant during communication interruptions.

[0066] When any energy storage converter is completely disconnected from the communication network, its neighborhood set is an empty set ( When this occurs, its control law is switched to local degraded control mode, and its distributed secondary control law is switched to autonomous mode that relies solely on local power deviation correction, i.e., state correction is performed solely based on the deviation between the actual local output power and the reference power. The expression is: ;

[0067] In the formula, the first Consistency variables in the next iteration From its own first Consistency variables in the next iteration Based on the active power deviation, it no longer relies on the consistency information of neighboring nodes for state updates, thus maintaining a basic responsiveness to load changes even in the event of a complete communication outage.

[0068] When any power-type energy storage converter is completely disconnected from the communication network, its consistency variables remain unchanged: ;

[0069] In the formula, the first Consistency variables in the next iteration Keep the first The value remains unchanged in the next iteration, and it will no longer be updated based on neighbor information, nor will it respond to local power deviation.

[0070] This strategy ensures that the system retains basic load response capabilities during communication outages.

[0071] The power supply fault tolerance strategy is as follows:

[0072] When a converter physical hardware failure causes a node to shut down and communication modules to cease operation, it will trigger a topology break and global paralysis in the sparse communication network. Therefore, this invention designs a power supply fault tolerance strategy, such as... Figure 5 As shown, when any grid-type converter is out of power operation due to physical hardware failure, the information relay reconfiguration mechanism is adopted to redefine the converter with physical hardware failure as an information relay node, and maintain the global communication topology connectivity of the multi-agent system by cutting off its local power deviation correction term.

[0073] For a faulty energy storage converter, the local power deviation correction term in its secondary control law is removed, so that the reconstructed control law retains only the neighbor information forwarding function. The expression is: ;

[0074] In the formula, the first Consistency variables in the next iteration Only by neighboring nodes Consistency variables in the next iteration The result is obtained by weighted summation based on communication weights, and no longer responds to local power deviations;

[0075] For a power-type energy storage converter that has failed, the same reconfiguration method as that for the aforementioned failed energy-type energy storage converter is used: the reconfigured control law retains only the neighbor information forwarding function and no longer responds to local power deviations, thereby causing it to lose its transient power response capability; since the power-type energy storage converter does not bear active power output in the steady state of the system, its shutdown under steady-state conditions will not cause a power surge to the system.

[0076] The information relay reconstruction mechanism preserves the communication capabilities of faulty nodes, maintains the global topological connectivity of the multi-agent system, and avoids global collaborative paralysis caused by a single point of physical failure.

[0077] S4. The control command output by the fault adaptive cooperative control strategy is used as the active power reference value and input to the virtual synchronous generator base controller of the grid-type converter. The virtual synchronous generator base controller integrates VSG control and voltage and current dual closed-loop control.

[0078] S5. The virtual synchronous generator base controller outputs a modulation voltage command, which is converted into a three-phase AC voltage waveform through inverse dq coordinate transformation. The three-phase AC voltage waveform is then converted into a three-phase PWM switching control signal through space vector pulse width modulation (SVPWM). The three-phase PWM switching control signal is applied to the inverter bridge arm of the grid-type converter to realize the physical control of the voltage and frequency of the entire virtual power plant islanded AC microgrid system.

[0079] In this invention, step S1 establishes a virtual power plant islanded AC microgrid system with a hybrid energy storage AC converter and a sparse communication network as the hardware and communication foundation. Step S2 collects electrical data from each converter and provides power calculation basis for fault adaptive control through interactive consistency variables. Step S3 designs a collaborative control strategy to deal with three types of faults based on the preceding system architecture and electrical data and outputs an active power reference command. Step S4 sends the command to the VSG basic controller to complete voltage and frequency closed-loop control. Step S5 generates a PWM drive signal to control the inverter bridge by inverse dq transformation and SVPWM of the modulated voltage output by the controller. Finally, the virtual power plant can still stably maintain the microgrid voltage and frequency under load changes, communication interruptions, and hardware failures, thereby improving the fault tolerance and operational stability of the hybrid energy storage system.

[0080] This invention has been described through embodiments. Those skilled in the art will understand that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of the invention. Furthermore, under the teachings of this invention, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of the invention. Therefore, this invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the protection scope of this invention.

Claims

1. A method for coordinated control of hybrid energy storage converters under virtual power plant fault conditions, characterized in that, Includes the following steps: S1. Construct a virtual power plant islanded AC microgrid system containing energy-type and power-type energy storage converters, and build a sparse communication network with each converter as a node; The virtual power plant islanded AC microgrid system includes at least one energy-type energy storage converter and one power-type energy storage converter; The isolated AC microgrid system also includes a DC power supply, an inverter, an LCL filter, a feeder impedance, and local loads. The DC power supply includes two types of energy storage units: batteries and supercapacitors. In the sparse communication network, each converter is regarded as an intelligent agent node. If there is a communication connection between two intelligent agent nodes, they are neighbor nodes. S2. Collect local electrical parameters of each converter to complete VSG basic control, and interact through a sparse communication network to achieve frequency synchronization and power distribution of multiple converters. The local electrical parameters of each converter include output voltage, current, local active power, reactive power, voltage amplitude and frequency obtained by power calculation; The active power reference value obtained by each converter after distributed collaborative computing is used as a consistency variable, and the consistency variable is interacted through a sparse network. S3, which integrates three types of strategies: dynamic decoupling control, communication anomaly response, and power failure tolerance, to form a fault adaptive cooperative control strategy. The dynamic decoupling control strategy is as follows: calculate the total power of the virtual power plant islanded AC microgrid system, and perform high-pass and low-pass filtering on the total power to obtain high-frequency and low-frequency components. Then, use a dynamic following algorithm based on actual power anchoring to generate active power reference commands for power-type energy storage converters and energy-type energy storage converters. The communication anomaly handling strategy is as follows: when any energy-type energy storage converter is completely disconnected from the communication network and its neighbor nodes are empty, the state correction is performed solely based on the deviation between the actual local output power and the reference power, expressed as: ； in, For the first One converter iteration Consistency variables at this time For the first One converter iteration Consistency variables at this time This is the deviation correction factor. This is the power control proportional coefficient. For the first The actual local output power of each converter It is the first Reference power of each converter; When any power-type energy storage converter is completely disconnected from the communication network, its consistency variable remains unchanged, as expressed by: ； The power supply fault tolerance strategy is as follows: when any converter stops operating due to a physical hardware failure, an information relay reconstruction mechanism is adopted to redefine the converter that has experienced a physical hardware failure as an information relay node. S4. Input the control commands output by the fault adaptive cooperative control strategy into the VSG basic controller of each converter. The S5 and VSG basic controller output modulation voltage is converted by dq inverse transformation and SVPWM to generate drive signals, which are used to regulate the voltage and frequency of the virtual power plant islanded AC microgrid system.

2. The hybrid energy storage converter collaborative control method for virtual power plant fault states according to claim 1, characterized in that, The expressions for the high-frequency and low-frequency components are as follows: ； in, , Relying on the first The low-frequency and high-frequency components of the total microgrid power calculated by each converter are then filtered. This is the adjustable time constant of the filtering stage. For complex variables, To rely on the first The total power of the global microgrid is obtained by distributed communication and interaction calculation of individual converters. This refers to the total number of energy storage converters. For the first Consistency variables for energy storage converters; The active power reference command expression is: ； in, , The first Active power reference commands for power-type energy storage converters and energy-type energy storage converters. , The first The actual output active power of power-type energy storage converters and energy-type energy storage converters. This represents the total number of power-type energy storage converters.

3. The hybrid energy storage converter collaborative control method for virtual power plant fault states according to claim 1, characterized in that, For a faulty converter, the local power deviation correction term in its secondary control law is removed. The reconstructed control law retains only the neighbor information forwarding function, and its expression is: ； in, For the first One converter iteration Consistency variables at this time For the first One converter iteration Consistency variables at this time For multi-agent communication weight coefficients, For converter The sequence number of the neighboring node with which there is a communication connection. For converter The neighborhood set.

4. The hybrid energy storage converter collaborative control method for virtual power plant fault states according to claim 1, characterized in that, In step S4, the VSG basic controller integrates VSG control and voltage and current dual closed-loop control.

5. The hybrid energy storage converter collaborative control method for virtual power plant fault states according to claim 1, characterized in that, Step S5 specifically involves: the VSG basic controller outputting a modulation voltage command, which is then converted into a three-phase AC voltage waveform via dq coordinate inverse transformation; the three-phase AC voltage waveform is then converted into a three-phase PWM switching control signal via space vector pulse width modulation; the three-phase PWM switching control signal is applied to the inverter bridge arm of the converter to achieve control of the voltage and frequency of the entire virtual power plant islanded AC microgrid system.

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