Networking type energy storage system and control method thereof

Abstract

The invention relates to the technical field of power grid energy storage control, and particularly discloses a network construction type energy storage system and a control method thereof, and the system comprises a parameter collection module which obtains the voltage, frequency, short-circuit capacity ratio, phase angle and other power grid operation parameters of a grid-connected point in real time; the scene recognition module judges the power grid scene of the energy storage system according to the acquired parameters, wherein the power grid scene comprises a weak power grid scene, a fault scene, an oscillation scene, a phase angle jump scene and a power loss scene; the strategy library module stores control strategies for each scene, including active / reactive control, active / reactive decoupling, overload support, low-frequency oscillation suppression, phase angle stabilization and black start strategies; and the adaptive control module retrieves and calls a corresponding strategy from a strategy library according to an identification result, performs adaptive control on the energy storage system, and realizes intelligent response and stable support for a complex power grid environment. According to the invention, intelligent response and stable support of the energy storage system to a complex power grid environment are effectively realized.

Description

Technical Field

[0001] This invention relates to the field of grid energy storage control technology, and more specifically, to a grid-type energy storage system and its control method. Background Technology

[0002] With the large-scale integration of new energy sources into the power grid, the power supply structure of the power system has undergone profound changes, and the strong grid characteristics traditionally supported by synchronous generators have gradually weakened. Against this backdrop, energy storage systems, as an important component of grid-connected power sources, are widely used in frequency regulation, voltage support, and black start of the power system.

[0003] However, most existing energy storage systems operate primarily in a grid-responsive mode, lacking deep awareness of grid operation and flexible response capabilities, making them ill-suited to complex and ever-changing grid environments. During grid operation, various scenarios frequently arise, including weak grids, short-circuit faults, low-frequency oscillations, abrupt phase changes, and power outages. These anomalies can severely impact grid stability and the safe operation of energy storage systems. Traditional energy storage control methods often employ fixed control strategies, failing to adapt to different operating scenarios. This results in poor control performance of energy storage systems in specific situations, and may even trigger system oscillations or secondary disturbances.

[0004] Therefore, how to enable energy storage systems to identify grid operation scenarios in real time and dynamically invoke them in conjunction with a multi-dimensional control strategy library has become a key technical issue in improving the stability and reliability of grid-based energy storage systems. Summary of the Invention

[0005] In view of this, the present invention proposes a grid-type energy storage system and its control method, aiming to solve the problem that existing energy storage systems cannot achieve real-time identification and adaptive control of various grid operation scenarios, resulting in insufficient stability and reliability in complex grid environments.

[0006] This invention proposes a grid-type energy storage system, comprising:

[0007] The parameter acquisition module is configured to acquire the grid operation parameters of the energy storage system at the grid connection point in real time. The grid operation parameters include the grid connection point voltage, grid connection point frequency, short-circuit capacity ratio, and phase angle.

[0008] The scene recognition module is electrically connected to the parameter acquisition module. The scene recognition module is configured to determine the power grid operation scenario in which the energy storage system is located based on the power grid operation parameters. The power grid operation scenarios include weak power grid scenarios, fault scenarios, oscillation scenarios, phase angle jump scenarios, and power outage scenarios.

[0009] The strategy library module is configured to store a variety of preset control strategies for different power grid operation scenarios. These control strategies include active power control strategy, reactive power control strategy, active power / reactive power decoupling control strategy, overload support control strategy, low frequency oscillation suppression control strategy, phase angle stabilization control strategy, and black start control strategy.

[0010] The adaptive control module is electrically connected to the scene recognition module and the strategy library module. The adaptive control module is configured to retrieve and call the corresponding control strategy from the strategy library module according to the power grid operation scenario determined by the scene recognition module, and perform adaptive control on the grid-type energy storage system according to the control strategy.

[0011] Furthermore, when the parameter acquisition module is configured to acquire power grid operating parameters in real time, it includes:

[0012] The parameter acquisition unit is configured to periodically receive voltage, current and power signals from the grid connection point of the energy storage system;

[0013] The feature extraction unit is electrically connected to the parameter acquisition unit. The feature extraction unit is configured to determine the amplitude and phase of the grid connection point voltage, the grid connection point frequency, the grid connection point short-circuit capacity ratio, and the grid connection point phase angle based on the voltage signal, current signal, and power signal.

[0014] The data preprocessing unit is electrically connected to the feature extraction unit. The data preprocessing unit is configured to filter and normalize the amplitude and phase of the grid connection point voltage, the grid connection point frequency, the grid connection point short-circuit capacity ratio, and the grid connection point phase angle, and generate standardized power grid operation parameter data.

[0015] Furthermore, the scene recognition module is configured to determine the grid operation scenario in which the energy storage system is located based on grid operation parameters, including:

[0016] The scene feature extraction unit is configured to extract feature indicators for each scene from the power grid operation parameters. The feature indicators include voltage fluctuation rate, frequency deviation, short-circuit capacity ratio threshold, phase angle change rate, and instantaneous active / reactive power values.

[0017] The scene determination unit is electrically connected to the scene feature extraction unit. The scene determination unit is configured to compare feature indicators with preset scene determination thresholds or patterns to determine the current power grid operation scene, wherein:

[0018] The scenario judgment unit is also equipped with preset short-circuit capacity ratio, preset instantaneous drop amplitude of grid connection point voltage, preset instantaneous impact amplitude of grid connection point current, preset oscillation frequency range, preset rate of change of grid connection point phase angle, preset effective value of grid connection point voltage, and preset grid connection point frequency value.

[0019] When the short-circuit capacity ratio is lower than the preset short-circuit capacity ratio, the scenario judgment unit determines it to be a weak power grid scenario;

[0020] When the voltage or current at the grid connection point changes instantaneously, and the voltage at the grid connection point is higher than the instantaneous drop amplitude of the preset grid connection point voltage, and / or when the current at the grid connection point is higher than the instantaneous surge amplitude of the preset grid connection point current, the scenario judgment unit determines it as a fault scenario.

[0021] When the grid connection frequency fluctuates continuously within a preset range and the fluctuation frequency is within a preset oscillation frequency range, the scenario judgment unit determines it as an oscillation scenario.

[0022] When the rate of change of the phase angle at the grid connection point is greater than the preset rate of change of the phase angle at the grid connection point, the scene judgment unit determines it as a phase angle jump scene.

[0023] When the grid connection point voltage is lower than the preset effective value of the grid connection point voltage, and when the grid connection point voltage frequency is lower than the preset grid connection point frequency value, and the duration is higher than or equal to the preset duration, the scenario judgment unit determines it as a power failure scenario.

[0024] Furthermore, when the adaptive control module is configured to invoke the corresponding control strategy for weak grid scenarios, it includes:

[0025] The weak grid strategy invocation unit is configured to retrieve and invoke enhanced grid construction control strategies for weak grid scenarios from the strategy library module. The enhanced grid construction control strategies include enhanced voltage support strategies and enhanced frequency support strategies.

[0026] The voltage support execution unit is electrically connected to the weak grid strategy invocation unit. The voltage support execution unit is configured to adjust the reactive power output of the energy storage system according to the enhanced voltage support strategy.

[0027] The frequency support execution unit is electrically connected to the weak grid strategy invocation unit. The frequency support execution unit is configured to adjust the active power output of the energy storage system according to the enhanced frequency support strategy.

[0028] Furthermore, when the adaptive control module is configured to invoke the corresponding control strategy for a fault scenario, it includes:

[0029] The fault policy invocation unit is configured to retrieve and invoke fault traversal control policies for fault scenarios from the policy library module;

[0030] The fault response execution unit is electrically connected to the fault strategy invocation unit. The fault response execution unit is configured to adjust the current limiting and voltage support modes inside the energy storage system during grid faults according to the fault ride-through control strategy.

[0031] The overload support execution unit is electrically connected to the fault strategy invocation unit. The overload support execution unit is configured to control the overload capacity of the energy storage system to output the instantaneous maximum power during a grid fault.

[0032] Furthermore, when the adaptive control module is configured to invoke the corresponding control strategy for an oscillation scenario, it includes:

[0033] The oscillation strategy invocation unit is configured to retrieve and invoke damping control strategies for oscillation scenarios from the strategy library module. The damping control strategies include virtual impedance control strategies and power angle oscillation suppression strategies.

[0034] The damping control execution unit is electrically connected to the oscillation strategy calling unit. The damping control execution unit is configured to adjust the output impedance or power angle control parameters of the energy storage system according to the damping control strategy.

[0035] The active inertia support execution unit is electrically connected to the oscillation strategy invocation unit. The active inertia support execution unit is configured to provide active inertia support when oscillation occurs, based on the inertia characteristics of simulated rotating machinery.

[0036] Furthermore, when the adaptive control module is configured to invoke the corresponding control strategy for phase angle jump scenarios and power failure scenarios, it includes:

[0037] The phase angle stabilization strategy invocation unit is configured to retrieve and invoke the phase angle stabilization control strategy for the phase angle jump scenario from the strategy library module. The phase angle stabilization control strategy includes the phase-locked loop reconstruction strategy and the power angle control strategy.

[0038] The phase angle stabilization execution unit is electrically connected to the phase angle stabilization strategy invocation unit. The phase angle stabilization execution unit is configured to adjust the output phase angle and frequency of the energy storage system when the grid phase angle changes according to the phase angle stabilization control strategy.

[0039] The black start strategy unit is configured to retrieve and call black start control strategies for power failure scenarios from the strategy library module. The black start control strategies include adaptive frequency and voltage start strategies.

[0040] The black start execution unit is electrically connected to the black start strategy invocation unit in the event of a complete power grid failure. The black start execution unit is configured to start the energy storage system and provide initial voltage and frequency support.

[0041] Furthermore, the adaptive control module is also configured to implement active / reactive power decoupling, including:

[0042] The active power control unit is configured to adjust the active power output of the energy storage system according to the grid operating parameters and control strategy instructions;

[0043] The reactive power control unit is configured to adjust the reactive power output of the energy storage system according to the grid operating parameters and control strategy instructions.

[0044] Furthermore, the adaptive control module also includes:

[0045] The performance evaluation unit is configured to monitor the operating status of the energy storage system and the grid operating parameters in real time after the control strategy is executed. The grid operating parameters include, but are not limited to, the grid connection point voltage, frequency, short-circuit capacity ratio and phase angle after the control strategy is executed.

[0046] The strategy correction unit, electrically connected to the performance evaluation unit, is configured to determine, based on the operating status and grid operating parameters, whether the currently executed control strategy has achieved the expected stable operation effect or grid recovery effect, and, based on the determination result, whether to correct the current control strategy, wherein:

[0047] When the power grid operating parameters after the control strategy is executed deviate from the stability target threshold by more than the preset operating parameters configured by the strategy correction unit, the strategy correction unit determines to correct the current control strategy.

[0048] When the energy storage system's response indicators and operating status fail to meet the preset performance requirements after the control strategy is executed, the strategy correction unit determines to correct the current control strategy.

[0049] When the recovery rate of the power grid operating parameters is lower than the preset recovery rate configured by the strategy correction unit after the control strategy is executed, the strategy correction unit determines to correct the current control strategy.

[0050] The strategy correction execution unit is electrically connected to the strategy correction unit. The strategy correction execution unit is configured to send a strategy correction instruction or parameter adjustment instruction to the strategy library module based on the performance evaluation results when it is determined that correction is needed, thereby optimizing the control strategy.

[0051] Compared with existing technologies, the advantages of this invention are as follows: The parameter acquisition module acquires key grid operation parameters such as voltage, frequency, short-circuit capacity ratio, and phase angle at the grid connection point of the energy storage system in real time, providing an accurate and reliable data foundation for scenario identification and control strategy selection. The scenario identification module analyzes the grid operation parameters to determine various grid operation scenarios, such as weak grid, fault, oscillation, phase angle jump, and power outage, enabling effective differentiation of different operating environments. Combined with various pre-set active power control, reactive power control, active / reactive power decoupling control, overload support control, low-frequency oscillation suppression control, phase angle stabilization control, and black start control strategies in the strategy library module, and automatically invoked and executed by the adaptive control module, the energy storage system can adaptively select the optimal control strategy for different operating scenarios. This improves the operational stability and reliability of the grid-connected energy storage system in complex grid environments, enhances the system's response to grid disturbances and abnormal events, and improves the overall safety, robustness, and control accuracy of the grid.

[0052] On the other hand, this application also provides a control method for a grid-type energy storage system, including:

[0053] Real-time acquisition of grid operation parameters at the grid connection point of the energy storage system, including grid connection point voltage, grid connection point frequency, short-circuit capacity ratio, and phase angle;

[0054] Based on the grid operating parameters, the grid operating scenario in which the energy storage system is located is determined. The grid operating scenarios include weak grid scenarios, fault scenarios, oscillation scenarios, phase angle jump scenarios, and power outage scenarios.

[0055] Based on the preset strategy library, the control strategy corresponding to the judgment result is retrieved and called. The preset strategy library stores a variety of control strategies for different power grid operation scenarios. The control strategies include active power control strategy, reactive power control strategy, active power / reactive power decoupling control strategy, overload support control strategy, low frequency oscillation suppression control strategy, phase angle stabilization control strategy and black start control strategy.

[0056] Adaptive control of the grid-type energy storage system is performed based on the invoked control strategy.

[0057] The system monitors the operating status of the energy storage system and the grid operating parameters in real time after the control strategy is executed, and determines whether to modify the control strategy based on the monitoring results.

[0058] It is understood that the grid-type energy storage system and its control method in the above embodiments of the present invention have the same beneficial effects, and will not be described again. Attached Figure Description

[0059] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0060] Figure 1 A functional block diagram of a grid-type energy storage system provided in an embodiment of the present invention;

[0061] Figure 2 This is a schematic diagram of a grid-type energy storage system provided in an embodiment of the present invention;

[0062] Figure 3 This is a flowchart illustrating a control method for a grid-type energy storage system provided in an embodiment of the present invention. Detailed Implementation

[0063] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the disclosure to those skilled in the art. It should be noted that, unless otherwise specified, embodiments and features in the embodiments of the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0064] like Figures 1-2 As shown in some embodiments of this application, this embodiment provides a grid-type energy storage system, including: a parameter acquisition module, a scene recognition module, a strategy library module, and an adaptive control module.

[0065] Specifically, the parameter acquisition module is configured to acquire real-time grid operation parameters at the grid connection point of the energy storage system. These grid operation parameters include grid connection point voltage, grid connection point frequency, short-circuit capacity ratio, and phase angle. The scenario identification module is electrically connected to the parameter acquisition module and is configured to determine the grid operation scenario in which the energy storage system is located based on the grid operation parameters. These grid operation scenarios include weak grid scenarios, fault scenarios, oscillation scenarios, phase angle jump scenarios, and power outage scenarios. The strategy library module is configured to store various preset control strategies for different grid operation scenarios. These control strategies include active power control strategies, reactive power control strategies, active power / reactive power decoupling control strategies, overload support control strategies, low-frequency oscillation suppression control strategies, phase angle stabilization control strategies, and black start control strategies. The adaptive control module is electrically connected to the scenario identification module and the strategy library module. This module is configured to retrieve and call the corresponding control strategies from the strategy library module based on the grid operation scenario determined by the scenario identification module, and then perform adaptive control on the grid-connected energy storage system according to these control strategies.

[0066] Understandably, by acquiring key grid operating parameters such as voltage, frequency, short-circuit capacity ratio, and phase angle at the energy storage system's grid connection point in real time through the parameter acquisition module, dynamic perception of the grid's operating status is achieved. This module can continuously collect multi-dimensional data from the grid connection point, providing accurate input information for subsequent operation scenario identification and control strategy selection, ensuring the integrity and reliability of the basic data for the energy storage system's operation in complex grid environments. Secondly, the scenario identification module analyzes the collected grid operating parameters, accurately classifying the grid environment in which the energy storage system operates into typical operating scenarios such as weak grid, fault, low-frequency oscillation, phase angle jump, and power outage. By comparing the correspondence between real-time parameters and the characteristics of various scenarios, the scenario identification module accurately judges the operating status of the energy storage system, enabling the system to determine the most suitable control response mode based on the current grid characteristics. In addition, the strategy library module pre-stores various control strategies for different operating scenarios, including active power control, reactive power control, active / reactive power decoupling control, overload support, low-frequency oscillation suppression, phase angle stabilization, and black start strategies. Based on the judgment results of the scene recognition module, the adaptive control module retrieves and calls the corresponding control strategy from the strategy library, and executes precise control operations on the energy storage system, realizing dynamic adjustment and adaptive response of the energy storage unit under different operating scenarios. Finally, through the synergistic effect of the above modules, this invention forms a closed-loop control mechanism: real-time perception—scene judgment—strategy matching—adaptive execution, enabling the grid-based energy storage system to automatically select the optimal control strategy for different grid disturbances or abnormal events, improving the system's response speed and accuracy to grid fluctuations, faults, and abnormal events, thereby enhancing the operational stability, reliability, and overall control capability of the energy storage system.

[0067] As can be seen, the grid-connected energy storage system includes a parameter acquisition module, a scenario identification module, a strategy library module, and an adaptive control module. The parameter acquisition module is configured to acquire real-time grid operating parameters at the energy storage system's grid connection point, including grid connection point voltage, grid connection point frequency, short-circuit capacity ratio, and phase angle. This module continuously monitors the grid connection point through sensors and data acquisition devices and transmits the acquired parameters to the scenario identification module. The scenario identification module is electrically connected to the parameter acquisition module and can determine the grid operating scenario in which the energy storage system operates based on the real-time acquired grid operating parameters, including weak grid scenarios, fault scenarios, oscillation scenarios, phase angle jump scenarios, and power outage scenarios. The scenario identification module analyzes characteristics such as grid connection point voltage, frequency fluctuation amplitude, and phase angle change rate to achieve accurate identification of different grid operating conditions. The strategy library module is configured to store various preset control strategies for different grid operating scenarios, including active power control strategies, reactive power control strategies, active / reactive power decoupling control strategies, overload support control strategies, low-frequency oscillation suppression control strategies, phase angle stabilization control strategies, and black start control strategies. Each control strategy can be individually invoked or combined according to different grid operation scenarios to achieve precise regulation of the energy storage system. The adaptive control module is electrically connected to the scenario identification module and the strategy library module. Based on the grid operation scenario determined by the scenario identification module, it retrieves and invokes the corresponding control strategy from the strategy library module and performs adaptive control on the energy storage system. For example, when the scenario identification module determines that it is a weak grid scenario, the adaptive control module can simultaneously activate the active power control strategy and the low-frequency oscillation suppression strategy to enhance the system's response capability to grid fluctuations; when it is determined to be a power outage scenario, the adaptive control module can invoke the black-start control strategy to enable the energy storage system to independently support grid recovery. Through the above embodiments, a real-time sensing, judgment, and adaptive control closed-loop mechanism is constructed, enabling the grid-connected energy storage system to automatically select the optimal control strategy according to different grid operation scenarios, thereby improving the system's stability, reliability, and regulation accuracy in complex grid environments.

[0068] Specifically, when the parameter acquisition module is configured to acquire grid operating parameters in real time, it includes: a parameter acquisition unit configured to periodically receive voltage, current, and power signals from the grid connection point of the energy storage system; a feature extraction unit electrically connected to the parameter acquisition unit, configured to determine the amplitude and phase of the grid connection point voltage, the grid connection point frequency, the grid connection point short-circuit capacity ratio, and the grid connection point phase angle based on the voltage, current, and power signals; and a data preprocessing unit electrically connected to the feature extraction unit, configured to perform filtering and normalization processing on the amplitude and phase of the grid connection point voltage, the grid connection point frequency, the grid connection point short-circuit capacity ratio, and the grid connection point phase angle, and generate standardized grid operating parameter data.

[0069] Understandably, the parameter acquisition module monitors the grid operation status at the energy storage system's connection point in real time. This module includes a parameter acquisition unit that periodically receives voltage, current, and power signals from the connection point, continuously acquiring fundamental grid operation data to provide a reliable source of raw data for subsequent feature analysis. Next, after acquiring the raw electrical signals, the feature extraction unit processes the voltage, current, and power signals to calculate key characteristic indicators such as the voltage amplitude and phase at the connection point, the connection point frequency, the short-circuit capacity ratio, and the phase angle. This process uses mathematical analysis of the phase relationship between voltage and current, and the correlation between the power signal and voltage amplitude, to quantitatively describe the dynamic characteristics of the grid, providing accurate fundamental data for determining the energy storage system's operating scenario and selecting control strategies. Furthermore, the data preprocessing unit is electrically connected to the feature extraction unit, filtering and normalizing the extracted grid feature data. Filtering effectively suppresses the effects of measurement noise and transient disturbances, while normalization unifies parameters of different dimensions within a standardized range, generating standardized grid operation parameter data. These standardized data can be directly used in the scene recognition module and adaptive control module to achieve stable response and high-precision control of the energy storage system under different grid operating conditions. Finally, through the above design of the parameter acquisition module, this invention achieves real-time, high-precision perception of the grid operating status at the grid connection point. Combined with feature extraction and data preprocessing mechanisms, complex and multidimensional grid signals can be transformed into standardized feature parameters that can be directly applied to control, laying a solid data foundation for the intelligent regulation and control of grid-connected energy storage systems.

[0070] As can be seen, the parameter acquisition module is configured to acquire real-time grid operating parameters at the energy storage system's grid connection point. This module includes a parameter acquisition unit, a feature extraction unit, and a data preprocessing unit. The parameter acquisition unit is configured to periodically receive voltage, current, and power signals from the energy storage system's grid connection point. Through this unit, voltage, current, and power information at the grid connection point can be continuously acquired, providing complete raw data for subsequent feature analysis. The feature extraction unit is electrically connected to the parameter acquisition unit. Based on the received voltage, current, and power signals, it calculates the amplitude and phase of the grid connection point voltage, the grid connection point frequency, the short-circuit capacity ratio, and the grid connection point phase angle. This unit analyzes the phase relationship between voltage and current and power characteristics to achieve a quantitative description of the grid characteristics at the grid connection point, providing accurate data for scenario identification and control strategy selection. The data preprocessing unit is electrically connected to the feature extraction unit and performs filtering and normalization processing on the extracted grid parameters. Filtering suppresses measurement noise and transient interference, while normalization unifies parameters with different dimensions into a standardized range, generating standardized grid operation parameter data that can be directly used in the scene recognition module and adaptive control module. Through the above embodiments, the parameter acquisition module can achieve real-time, high-precision sensing of the grid operation status at the energy storage system's grid connection point, and transform complex, multi-dimensional grid signals into standardized feature data that can be directly applied to subsequent control, providing a reliable data foundation for the intelligent regulation of grid-connected energy storage systems.

[0071] Specifically, the scene recognition module is configured to determine the grid operation scenario in which the energy storage system is located based on grid operation parameters. This includes: a scene feature extraction unit, configured to extract feature indicators for each scenario from the grid operation parameters, including voltage fluctuation rate, frequency deviation, short-circuit capacity ratio threshold, phase angle change rate, and instantaneous active / reactive power values; and a scene judgment unit, electrically connected to the scene feature extraction unit, configured to compare the feature indicators with preset scene judgment thresholds or patterns to determine the current grid operation scenario. The scene judgment unit is further configured with preset short-circuit capacity ratio, preset instantaneous voltage drop amplitude at the grid connection point, preset instantaneous impact amplitude of the grid connection point current, preset oscillation frequency range, preset rate of change of the phase angle at the grid connection point, preset effective value of the grid connection point voltage, and preset grid connection point frequency... The following parameters are considered: short-circuit capacity ratio; when the short-circuit capacity ratio is lower than the preset short-circuit capacity ratio, the scenario judgment unit determines it as a weak grid scenario; when the voltage or current at the grid connection point changes instantaneously, and the voltage at the grid connection point is higher than the preset instantaneous drop amplitude of the grid connection point voltage, and / or when the current at the grid connection point is higher than the preset instantaneous impact amplitude of the grid connection point current, the scenario judgment unit determines it as a fault scenario; when the frequency at the grid connection point fluctuates continuously within a preset range, and the fluctuation frequency is within a preset oscillation frequency range, the scenario judgment unit determines it as an oscillation scenario; when the rate of change of the phase angle at the grid connection point is greater than the preset rate of change of the phase angle at the grid connection point, the scenario judgment unit determines it as a phase angle jump scenario; when the voltage at the grid connection point is lower than the preset effective value of the grid connection point voltage, and when the frequency of the grid connection point voltage is lower than the preset grid connection point frequency value, and the duration is higher than or equal to the preset duration, the scenario judgment unit determines it as a power outage scenario.

[0072] Specifically, when the adaptive control module is configured to invoke corresponding control strategies for weak grid scenarios, it includes: a weak grid strategy invocation unit, configured to retrieve and invoke enhanced grid construction control strategies for weak grid scenarios from the strategy library module, the enhanced grid construction control strategies including enhanced voltage support strategies and enhanced frequency support strategies; a voltage support execution unit, electrically connected to the weak grid strategy invocation unit, configured to adjust the reactive power output of the energy storage system according to the enhanced voltage support strategy; and a frequency support execution unit, electrically connected to the weak grid strategy invocation unit, configured to adjust the active power output of the energy storage system according to the enhanced frequency support strategy.

[0073] Specifically, when the adaptive control module is configured to invoke the corresponding control strategy for a fault scenario, it includes: a fault strategy invocation unit, configured to retrieve and invoke the fault ride-through control strategy for the fault scenario from the strategy library module; a fault response execution unit, electrically connected to the fault strategy invocation unit, configured to adjust the current limiting and voltage support modes inside the energy storage system during a grid fault according to the fault ride-through control strategy; and an overload support execution unit, electrically connected to the fault strategy invocation unit, configured to control the overload capacity of the energy storage system to output the instantaneous maximum power during a grid fault.

[0074] Specifically, when the adaptive control module is configured to invoke the corresponding control strategy for an oscillation scenario, it includes: an oscillation strategy invocation unit, configured to retrieve and invoke a damping control strategy for the oscillation scenario from the strategy library module, the damping control strategy including a virtual impedance control strategy and a power angle oscillation suppression strategy; a damping control execution unit, electrically connected to the oscillation strategy invocation unit, configured to adjust the output impedance or power angle control parameters of the energy storage system according to the damping control strategy; and an active inertia support execution unit, electrically connected to the oscillation strategy invocation unit, configured to provide active inertia support when oscillation occurs based on the inertia characteristics of simulated rotating machinery.

[0075] Specifically, when the adaptive control module is configured to invoke corresponding control strategies for phase angle jump scenarios and power outage scenarios, it includes: a phase angle stabilization strategy invocation unit, configured to retrieve and invoke phase angle stabilization control strategies for phase angle jump scenarios from the strategy library module, the phase angle stabilization control strategies including phase-locked loop reconfiguration strategies and power angle control strategies; a phase angle stabilization execution unit, electrically connected to the phase angle stabilization strategy invocation unit, configured to adjust the output phase angle and frequency of the energy storage system when a phase angle jump occurs in the power grid, according to the phase angle stabilization control strategy; a power outage black start strategy unit, configured to retrieve and invoke black start control strategies for power outage scenarios from the strategy library module, wherein the black start control strategies include adaptive frequency and voltage start strategies; and a black start execution unit, electrically connected to the power outage black start strategy invocation unit, configured to start the energy storage system and provide initial voltage and frequency support when the power grid is completely de-energized.

[0076] Understandably, the scenario identification module determines the grid operation scenario in which the energy storage system operates. This module includes a scenario feature extraction unit and a scenario judgment unit. The scenario feature extraction unit extracts key characteristic indicators from grid operating parameters, such as voltage fluctuation rate, frequency deviation, short-circuit capacity ratio threshold, phase angle change rate, and instantaneous active / reactive power values, to comprehensively describe the dynamic characteristics of the grid. The scenario judgment unit compares these characteristic indicators with preset scenario judgment thresholds or modes, and combines them with preset conditions such as short-circuit capacity ratio, instantaneous voltage drop amplitude, current surge amplitude, oscillation frequency range, phase angle change rate, and effective voltage and frequency values ​​to determine the current grid operation scenario, achieving accurate identification of typical operating conditions such as weak grids, faults, oscillations, phase angle jumps, and power outages. Specifically, for different determined grid operation scenarios, the adaptive control module calls corresponding control strategies to achieve dynamic adjustment and closed-loop control of the energy storage system. For weak grid scenarios, the weak grid strategy invocation unit retrieves enhanced grid control strategies from the strategy library, including enhanced voltage support strategies and enhanced frequency support strategies. The voltage support execution unit adjusts the reactive power output of the energy storage system according to the voltage support strategy, while the frequency support execution unit adjusts the active power output according to the frequency support strategy, thereby improving the voltage and frequency stability of the energy storage system under weak grid conditions. Secondly, for fault scenarios, the fault strategy invocation unit retrieves fault ride-through control strategies from the strategy library. During grid faults, the fault response execution unit adjusts the internal current limiting and voltage support modes of the energy storage system according to the strategies. The overload support execution unit controls the instantaneous maximum power output of the energy storage system during faults, ensuring the system can quickly respond to grid faults and maintain power supply capacity. Simultaneously, for oscillation scenarios, the oscillation strategy invocation unit invokes damping control strategies from the strategy library, including virtual impedance control strategies and power angle oscillation suppression strategies. The damping control execution unit adjusts the output impedance or power angle control parameters of the energy storage system according to the damping strategy. The active inertia support execution unit provides active inertia support when oscillations occur by simulating the inertia characteristics of rotating machinery, thereby suppressing low-frequency grid oscillations and improving the dynamic stability of the system. Furthermore, for phase angle jump scenarios and power outage scenarios, the phase angle stabilization strategy invocation unit retrieves phase angle stabilization control strategies from the strategy library, including phase-locked loop reconfiguration strategies and power angle control strategies. The phase angle stabilization execution unit adjusts the output phase angle and frequency of the energy storage system when the grid phase angle jumps. The power outage black start strategy unit invokes black start control strategies, including adaptive frequency and voltage start strategies. The black start execution unit starts the energy storage system when the grid is completely de-energized, providing initial voltage and frequency support to achieve the black start function. Finally, through the above design, this invention forms a closed-loop control mechanism with grid operation scenario identification as its core: real-time feature extraction—scenario determination—strategy invocation—adaptive execution.This mechanism can automatically match the optimal control strategy for different grid disturbances or abnormal events, enabling grid-type energy storage systems to achieve high-precision regulation and rapid response in various operating scenarios such as weak grids, faults, oscillations, phase angle jumps and power outages, thereby significantly improving system stability, reliability and overall grid security.

[0077] As can be seen, the scenario identification module is configured to determine the grid operation scenario in which the energy storage system operates based on grid operating parameters. The scenario identification module includes a scenario feature extraction unit and a scenario judgment unit. The scenario feature extraction unit extracts key characteristic indicators from the grid operating parameters, such as voltage fluctuation rate, frequency deviation, short-circuit capacity ratio threshold, phase angle change rate, and instantaneous active / reactive power values. The scenario judgment unit compares these characteristic indicators with preset scenario judgment thresholds or modes, and combines them with preset conditions such as short-circuit capacity ratio, instantaneous voltage drop amplitude, current surge amplitude, oscillation frequency range, phase angle change rate, and effective voltage and frequency values ​​to determine the current grid operation scenario in which the energy storage system operates, including weak grid scenarios, fault scenarios, oscillation scenarios, phase angle jump scenarios, and power outage scenarios. For different grid operation scenarios, the adaptive control module calls the corresponding control strategies in the strategy library to achieve dynamic adjustment and adaptive control of the energy storage system. For weak grid scenarios, the weak grid strategy invocation unit of the adaptive control module retrieves enhanced grid control strategies from the strategy library, including enhanced voltage support strategies and enhanced frequency support strategies. The voltage support execution unit adjusts the reactive power output of the energy storage system, and the frequency support execution unit adjusts the active power output, thereby improving the voltage and frequency stability of the system under weak grid conditions. For fault scenarios, the fault strategy invocation unit retrieves fault ride-through control strategies from the strategy library. The fault response execution unit adjusts the internal current limiting and voltage support mode of the energy storage system during grid faults. At the same time, the overload support execution unit controls the energy storage system to output the instantaneous maximum power during faults, ensuring rapid response and power supply capability. For oscillation scenarios, the oscillation strategy invocation unit retrieves damping control strategies from the strategy library, including virtual impedance control strategies and power angle oscillation suppression strategies. The damping control execution unit adjusts the output impedance and power angle control parameters of the energy storage system. At the same time, the active inertia support execution unit provides active inertia support based on the inertia characteristics of simulated rotating machinery when oscillations occur, to suppress oscillations and improve the dynamic stability of the system. For phase angle jump scenarios, the phase angle stabilization strategy invocation unit retrieves phase angle stabilization control strategies from the strategy library, including phase-locked loop reconfiguration strategies and power angle control strategies. The phase angle stabilization execution unit adjusts the output phase angle and frequency of the energy storage system when the grid phase angle jumps. For power outage scenarios, the power outage black start strategy unit retrieves black start control strategies from the strategy library, including adaptive frequency and voltage start strategies. The black start execution unit starts the energy storage system when the grid is completely de-energized, providing initial voltage and frequency support to achieve the system's black start function.

[0078] As shown in Table 1, the power grid operation scenarios and corresponding control strategies and execution units are as follows:

[0079]

[0080]

[0081] In summary, by using the scene recognition module to determine the grid operation scenario and the adaptive control module to dynamically invoke various control strategies, the energy storage system can respond quickly and intelligently regulate according to different grid operation states, thereby effectively improving the operational stability, reliability, and adaptability of the grid-based energy storage system.

[0082] Specifically, the adaptive control module is also configured to implement active / reactive power decoupling, including: an active power control unit configured to adjust the active power output of the energy storage system according to grid operating parameters and control strategy instructions; and a reactive power control unit configured to adjust the reactive power output of the energy storage system according to grid operating parameters and control strategy instructions.

[0083] It is understandable that the adaptive control module is configured to implement the active / reactive power decoupling control function of the energy storage system. Through this function, the energy storage system can simultaneously and independently adjust both active and reactive power outputs, thereby improving the system's responsiveness and adjustment accuracy to dynamic changes in the power grid. Specifically, the adaptive control module includes an active power control unit and a reactive power control unit. The active power control unit calculates and adjusts the active power output of the energy storage system based on real-time acquired grid operating parameters and control strategy instructions from the adaptive control strategy library to meet the requirements of grid frequency regulation, power support, and oscillation suppression. Simultaneously, the reactive power control unit also independently adjusts the reactive power output of the energy storage system based on grid operating parameters and control strategy instructions to maintain grid connection point voltage stability and support voltage regulation strategies. In this way, changes in active power do not affect reactive power regulation, and vice versa, achieving decoupling control of active and reactive power.

[0084] As can be seen, the adaptive control module includes an active power control unit and a reactive power control unit. The active power control unit calculates and adjusts the active power output of the energy storage system based on real-time acquired grid operating parameters and corresponding control strategy instructions from the control strategy library. For example, when a grid frequency deviation occurs, the active power control unit increases or decreases the active power output of the energy storage system according to the deviation magnitude and control strategy instructions, thereby supporting the grid frequency. Simultaneously, the reactive power control unit independently adjusts the reactive power output of the energy storage system according to grid operating parameters and control strategy instructions. For example, when the grid connection point voltage fluctuates, the reactive power control unit increases or decreases the reactive power output of the energy storage system according to the voltage deviation and control strategy instructions to stabilize the grid connection point voltage. Finally, through the independent adjustment of the active power control unit and the reactive power control unit, this embodiment achieves decoupled control of active and reactive power, ensuring that adjustments to active power do not affect reactive power adjustments, and vice versa. This decoupled control method ensures that the energy storage system can quickly respond to power adjustment needs in different operating scenarios under complex grid environments, improving system reliability and grid dynamic stability.

[0085] Specifically, the adaptive control module further includes: a performance evaluation unit configured to monitor the operating status of the energy storage system and grid operating parameters in real time after the control strategy is executed. These grid operating parameters include, but are not limited to, the grid connection point voltage, frequency, short-circuit capacity ratio, and phase angle after the control strategy is executed; and a strategy correction unit electrically connected to the performance evaluation unit. The strategy correction unit is configured to determine, based on the operating status and grid operating parameters, whether the currently executed control strategy has achieved the expected stable operation effect or grid recovery effect, and, based on the determination result, whether to correct the current control strategy. Specifically, if the grid operating parameters after the control strategy is executed deviate from the stability target threshold by more than the value specified by the strategy correction unit... When the preset operating parameters are set, the strategy correction unit determines to correct the current control strategy; when the energy storage system response indicators and operating status fail to meet the preset performance indicators after the control strategy is executed, the strategy correction unit determines to correct the current control strategy; when the recovery speed of the grid operating parameters after the control strategy is executed is lower than the preset recovery speed configured by the strategy correction unit, the strategy correction unit determines to correct the current control strategy; the strategy correction execution unit is electrically connected to the strategy correction unit and is configured to send a strategy correction command or parameter adjustment command to the strategy library module based on the performance evaluation results when it is determined that correction is needed, thereby optimizing the control strategy.

[0086] It is understood that the adaptive control module further includes a performance evaluation unit and a strategy correction unit, used to achieve real-time monitoring and optimization of the execution effect of the energy storage system control strategy. During the execution of the control strategy by the energy storage system, the performance evaluation unit continuously acquires and analyzes the operating status of the energy storage system and grid operating parameters. These grid operating parameters include, but are not limited to, the grid connection point voltage, frequency, short-circuit capacity ratio, and phase angle after the control strategy is executed. Through real-time monitoring, the performance evaluation unit can determine the response effect of the energy storage system and the recovery status of the grid under different grid operating scenarios. The strategy correction unit is electrically connected to the performance evaluation unit and, based on the real-time data provided by the performance evaluation unit, judges the effectiveness of the currently executed control strategy. Specifically, when the grid operating parameters after the control strategy is executed deviate from the preset stability target threshold by more than the operating parameters configured by the strategy correction unit, the strategy correction unit determines that the current control strategy needs to be corrected; when the response indicators of the energy storage system do not meet the preset performance requirements, or the grid recovery speed is lower than the preset recovery speed configured by the strategy correction unit, it is also determined that the control strategy needs to be adjusted. The strategy correction execution unit is electrically connected to the strategy correction unit. When the strategy correction unit determines that correction is needed, the strategy correction execution unit sends a strategy correction command or parameter adjustment command to the strategy library module based on the performance evaluation results to optimize the control strategy. Through the above mechanism, this embodiment can achieve closed-loop optimization of the energy storage system control strategy, ensuring that the energy storage system can continuously adapt to the dynamic changes of the power grid under different power grid operating scenarios, improving the system's operational stability and power grid support capabilities, while effectively preventing the control strategy from failing due to environmental changes or causing secondary disturbances.

[0087] As can be seen, the adaptive control module further includes a performance evaluation unit, a strategy correction unit, and a strategy correction execution unit, used for real-time monitoring and closed-loop optimization of the execution effect of the energy storage system control strategy. The performance evaluation unit is configured to acquire and analyze the operating status of the energy storage system and grid operating parameters in real time after the energy storage system executes the control strategy. The grid operating parameters include, but are not limited to, the grid connection point voltage, frequency, short-circuit capacity ratio, and phase angle after the control strategy is executed. The performance evaluation unit can be used to evaluate the response effect of the energy storage system under different grid operating scenarios and the recovery status of the grid state, thereby providing a data basis for strategy optimization. The strategy correction unit is electrically connected to the performance evaluation unit and determines whether the currently executed control strategy has achieved the expected effect based on the operating status and grid operating parameters provided by the performance evaluation unit. Specifically, when the grid operating parameters after the control strategy is executed deviate from the preset stability target threshold by more than the preset operating parameters of the strategy correction unit, the strategy correction unit determines that the current control strategy needs to be corrected; when the response indicators of the energy storage system fail to meet the preset performance indicator requirements, the strategy correction unit also determines that correction is needed; in addition, when the recovery speed of the grid operating parameters is lower than the preset recovery speed of the strategy correction unit, a strategy correction determination will also be triggered. The strategy correction execution unit is electrically connected to the strategy correction unit. When the strategy correction unit determines that correction is needed, the strategy correction execution unit sends a strategy correction command or parameter adjustment command to the strategy library module based on the performance evaluation results to optimize the current control strategy. Through this mechanism, this embodiment can achieve adaptive closed-loop optimization of the control strategy, enabling the energy storage system to adjust its control behavior in a timely manner according to the dynamic changes in grid operation, improving grid support capabilities and the operational stability of the energy storage system, while effectively preventing the control strategy from failing due to environmental changes or causing secondary disturbances.

[0088] In the above embodiments, the parameter acquisition module acquires key grid operation parameters such as voltage, frequency, short-circuit capacity ratio, and phase angle at the grid connection point of the energy storage system in real time, providing an accurate and reliable data foundation for scenario identification and control strategy selection. The scenario identification module analyzes the grid operation parameters to determine various grid operation scenarios, such as weak grid, fault, oscillation, phase angle jump, and power outage, enabling effective differentiation of different operating environments. Combined with various pre-set active power control, reactive power control, active / reactive power decoupling control, overload support control, low-frequency oscillation suppression control, phase angle stabilization control, and black start control strategies in the strategy library module, and automatically invoked and executed by the adaptive control module, the energy storage system can adaptively select the optimal control strategy for different operating scenarios. This improves the operational stability and reliability of the grid-connected energy storage system in complex grid environments, enhances the system's response to grid disturbances and abnormal events, and improves the overall safety, robustness, and control accuracy of the grid.

[0089] In another preferred embodiment based on the above embodiments, such as Figure 3 As shown, this embodiment provides a control method for a grid-type energy storage system, including:

[0090] Step S100: Real-time acquisition of grid operation parameters at the grid connection point of the energy storage system. The grid operation parameters include grid connection point voltage, grid connection point frequency, short-circuit capacity ratio, and phase angle.

[0091] Step S200: Based on the grid operating parameters, determine the grid operating scenario in which the energy storage system is located. The grid operating scenarios include weak grid scenario, fault scenario, oscillation scenario, phase angle jump scenario, and power outage scenario.

[0092] Step S300: Based on the preset strategy library, retrieve and call the control strategy corresponding to the judgment result. The preset strategy library stores a variety of control strategies for different power grid operation scenarios. The control strategies include active power control strategy, reactive power control strategy, active power / reactive power decoupling control strategy, overload support control strategy, low-frequency oscillation suppression control strategy, phase angle stabilization control strategy, and black start control strategy.

[0093] Step S400: Perform adaptive control on the grid-type energy storage system according to the invoked control strategy;

[0094] Step S500: Monitor the operating status of the energy storage system and the grid operating parameters after the execution of the control strategy in real time, and determine whether to modify the control strategy based on the monitoring results.

[0095] It is understood that the grid-type energy storage system and its control method in the above embodiments of the present invention have the same beneficial effects, and will not be described again.

[0096] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program goods. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program goods embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0097] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program goods according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0098] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0099] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0100] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A grid-forming energy storage system, characterized by, Comprise: Parameter acquisition module is configured to obtain the grid operation parameter of energy storage system grid-connected point in real time, wherein the grid operation parameter includes grid-connected point voltage, grid-connected point frequency, short-circuit capacity ratio and phase angle; Scene recognition module is electrically connected with parameter acquisition module, scene recognition module is configured to determine the grid operation scene of energy storage system according to grid operation parameter, grid operation scene includes weak grid scene, fault scene, oscillation scene, phase angle jump scene and power failure scene; Strategy library module is configured to store multiple control strategies preset for different grid operation scenes, wherein the control strategy includes active control strategy, reactive control strategy, active / reactive decoupling control strategy, overload support control strategy, low-frequency oscillation suppression control strategy, phase angle stability control strategy and black start control strategy; Adaptive control module is electrically connected with scene recognition module and strategy library module, adaptive control module is configured to retrieve and call corresponding control strategy from strategy library module according to grid operation scene determined by scene recognition module, and to adaptively control grid-connected energy storage system according to control strategy.

2. The networked energy storage system of claim 1, wherein When parameter acquisition module is configured to obtain grid operation parameter in real time, it comprises: Parameter acquisition unit is configured to periodically receive voltage signal, current signal and power signal from energy storage system grid-connected point; Feature extraction unit is electrically connected with parameter acquisition unit, feature extraction unit is configured to determine grid-connected point voltage amplitude and phase, grid-connected point frequency, grid-connected point short-circuit capacity ratio and grid-connected point phase angle according to voltage signal, current signal and power signal; Data preprocessing unit is electrically connected with feature extraction unit, data preprocessing unit is configured to filter and normalize grid-connected point voltage amplitude and phase, grid-connected point frequency, grid-connected point short-circuit capacity ratio and grid-connected point phase angle, and generate standardized grid operation parameter data.

3. The grid-enabled energy storage system of claim 2, wherein, When scene recognition module is configured to determine the grid operation scene of energy storage system according to grid operation parameter, it comprises: Scene feature extraction unit is configured to extract feature index of each scene from grid operation parameter, wherein the feature index includes voltage fluctuation rate, frequency deviation, short-circuit capacity ratio threshold, phase angle change rate and active / reactive power instantaneous value; Scene judgment unit is electrically connected with scene feature extraction unit, scene judgment unit is configured to compare feature index with preset scene judgment threshold or mode to determine the current grid operation scene, wherein: Scene judgment unit is also provided with preset short-circuit capacity ratio, preset grid-connected point voltage instantaneous drop amplitude, preset grid-connected point current instantaneous impact amplitude, preset oscillation frequency interval, preset grid-connected point phase angle change rate, preset grid-connected point voltage effective value and preset grid-connected point frequency value; When short-circuit capacity ratio is lower than preset short-circuit capacity ratio, scene judgment unit determines weak grid scene; When grid-connected point voltage or current occurs instantaneous change, and grid-connected point voltage is higher than preset grid-connected point voltage instantaneous drop amplitude, and / or when grid-connected point current is higher than preset grid-connected point current instantaneous impact amplitude, scene judgment unit determines fault scene; When the grid point frequency continues to fluctuate within a preset range, and the fluctuation frequency is in a preset oscillation frequency interval, the scene judgment unit determines that the scene is an oscillation scene; When the grid point phase angle change rate is greater than a preset grid point phase angle change rate, the scene judgment unit determines that the scene is a phase angle jump scene; When the grid point voltage is lower than a preset grid point voltage effective value, and when the grid point voltage frequency is lower than a preset grid point frequency value, and the duration is higher than or equal to a preset duration, the scene judgment unit determines that the scene is a power failure scene.

4. The networked energy storage system of claim 3, wherein, When the adaptive control module is configured to call the corresponding control strategy for a weak grid scene, it includes: A weak grid strategy calling unit is configured to retrieve and call an enhanced grid forming control strategy for a weak grid scene from the strategy library module, and the enhanced grid forming control strategy includes an enhanced voltage support strategy and an enhanced frequency support strategy; A voltage support execution unit is electrically connected with the weak grid strategy calling unit, and the voltage support execution unit is configured to adjust the reactive power output of the energy storage system according to the enhanced voltage support strategy; A frequency support execution unit is electrically connected with the weak grid strategy calling unit, and the frequency support execution unit is configured to adjust the active power output of the energy storage system according to the enhanced frequency support strategy.

5. The networked energy storage system of claim 3, wherein, When the adaptive control module is configured to call the corresponding control strategy for a fault scene, it includes: A fault strategy calling unit is configured to retrieve and call a fault ride-through control strategy for a fault scene from the strategy library module; A fault response execution unit is electrically connected with the fault strategy calling unit, and the fault response execution unit is configured to adjust the current limit and voltage support mode inside the energy storage system during the grid fault according to the fault ride-through control strategy; An overload support execution unit is electrically connected with the fault strategy calling unit, and the overload support execution unit is configured to control the overload capability output transient maximum power of the energy storage system during the grid fault.

6. The networked energy storage system of claim 3, wherein, When the adaptive control module is configured to call the corresponding control strategy for an oscillation scene, it includes: An oscillation strategy calling unit is configured to retrieve and call a damping control strategy for an oscillation scene from the strategy library module, and the damping control strategy includes a virtual impedance control strategy and a power angle oscillation suppression strategy; A damping control execution unit is electrically connected with the oscillation strategy calling unit, and the damping control execution unit is configured to adjust the output impedance or power angle control parameter of the energy storage system according to the damping control strategy; An active inertia support execution unit is electrically connected with the oscillation strategy calling unit, and the active inertia support execution unit is configured to provide active inertia support based on the inertia characteristics of the simulated rotating machinery when the oscillation occurs.

7. The networked energy storage system of claim 3, wherein, When the adaptive control module is configured to call the corresponding control strategy for a phase angle jump scene and a power failure scene, it includes: A phase angle stability strategy calling unit is configured to retrieve and call a phase angle stability control strategy for a phase angle jump scene from the strategy library module, and the phase angle stability control strategy includes a phase-locked loop reconstruction strategy and a power angle control strategy; The phase angle stability execution unit is electrically connected with the phase angle stability strategy calling unit, and is configured to adjust the output phase angle and frequency of the energy storage system when the grid phase angle jumps according to the phase angle stability control strategy. The black-start strategy unit is configured to retrieve and call the black-start control strategy for the black-out scenario from the strategy library module, wherein the black-start control strategy includes the adaptive frequency and voltage start strategy. The black-start execution unit is electrically connected with the black-start strategy calling unit, and is configured to start the energy storage system and provide initial voltage and frequency support when the grid is completely blacked out.

8. The network infrastructure energy storage system of claim 1, wherein, The adaptive control module is further configured to implement an active / reactive decoupling function, including: The active power control unit is configured to adjust the active power output of the energy storage system according to the grid operating parameters and control strategy instructions. The reactive power control unit is configured to adjust the reactive power output of the energy storage system according to the grid operating parameters and control strategy instructions.

9. The network infrastructure energy storage system of claim 1, wherein, The adaptive control module further includes: The performance evaluation unit is configured to monitor the operating state of the energy storage system and the grid operating parameters in real time after executing the control strategy, and the grid operating parameters include but are not limited to the grid point voltage, frequency, short circuit capacity ratio and phase angle after the control strategy is executed. The strategy correction unit is electrically connected with the performance evaluation unit, and is configured to determine whether the currently executed control strategy achieves the expected stable operation effect or grid recovery effect according to the operating state and grid operating parameters, and determine whether to correct the current control strategy according to the judgment result, wherein: When the grid operating parameters after the control strategy is executed deviate from the stable target threshold by more than the preset operating parameters configured by the strategy correction unit, the strategy correction unit determines to correct the current control strategy; When the response index of the energy storage system after the control strategy is executed and the operating state fail to meet the preset performance index requirements, the strategy correction unit determines to correct the current control strategy; When the grid operating parameters after the control strategy is executed recover at a speed lower than the preset recovery speed configured by the strategy correction unit, the strategy correction unit determines to correct the current control strategy; The strategy correction execution unit is electrically connected with the strategy correction unit, and is configured to send a strategy correction instruction or a parameter adjustment instruction to the strategy library module based on the performance evaluation result when it is determined that correction is needed, to optimize the control strategy.

10. A grid-forming energy storage system control method, applicable to a grid-forming energy storage system according to any one of claims 1-9, characterized in that, including: Real-time acquisition of grid operating parameters at the grid point of the energy storage system, including grid point voltage, grid point frequency, short circuit capacity ratio and phase angle; According to the grid operating parameters, the grid operating scenario of the energy storage system is determined, including weak grid scenario, fault scenario, oscillation scenario, phase angle jump scenario and black-out scenario; Based on a preset strategy library, a control strategy corresponding to the determination result is retrieved and called, the preset strategy library stores a plurality of control strategies for different power grid operation scenarios, and the control strategies include active power control strategies, reactive power control strategies, active / reactive power decoupling control strategies, overload support control strategies, low-frequency oscillation suppression control strategies, phase angle stability control strategies, and black start control strategies; The grid-forming energy storage system is adaptively controlled according to the called control strategy; The running state of the energy storage system and the power grid operation parameters after the execution of the control strategy are monitored in real time, and whether the control strategy is modified is judged according to the monitoring result.

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