Energy storage device control method and system based on sensitivity analysis

Abstract

The application discloses a kind of energy storage device control method and system based on sensitivity analysis, which comprises: when any device in power grid system is overloaded, according to the energy storage charge-discharge state required to eliminate overload and the current power state of energy storage device, it is judged whether the energy storage device is consistent with the required energy storage state;If consistent, the method of sensitivity analysis is used to carry out energy storage charge-discharge power online setting, determine the optimal control quantity, and issue the first control strategy to the stability control device matched with any device, otherwise issue the second control strategy.When any device meets the set start condition, the stability control device matched with any device executes the first control strategy or the second control strategy.The system comprises: energy storage state judging module, online control module, offline control module and stability control device.Through the application, power supply reliability and stability can be effectively improved, and flexible adjustment can be realized to avoid multiple adjustments and pre-adjustment, and optimal control is realized.

Description

Technical Field

[0001] This application relates to the field of power system safety control technology, and in particular to a control method and system for energy storage devices based on sensitivity analysis. Background Technology

[0002] Automatic safety devices (AS / RS) are automatic control devices that play a controlling role in ensuring the safe and stable operation of a power grid when faults or abnormal operations occur. Eliminating overcurrent in equipment after a fault is a crucial function of AS / RS. Therefore, how to utilize AS / RS to perform overcurrent control on equipment after fault elimination is an important technical issue.

[0003] Currently, commonly used methods include: changing the grid connection method, disconnecting generating units, shedding loads, and manually adjusting energy storage capacity. Specifically, changing the grid connection method involves either closing some lines to increase power flow transmission channels or changing the switching mode of bus couplers within substations to move loads out, thereby adjusting the power flow distribution. Disconnecting generating units is used when overloaded equipment is located on a critical power flow transmission channel at the power plant; this can be done by disconnecting generators to reduce the power flow transmitted through that channel. Shedding loads mainly involves removing a portion of the load from the receiving-end system for overloaded equipment, thereby reducing the power flow transmitted by the equipment. Manual adjustment of energy storage capacity is mainly achieved by dispatchers setting charging and discharging power based on experience to avoid overcurrent.

[0004] However, current conventional methods have various limitations. Changing the grid wiring pattern is problematic because the grid's operating mode is relatively fixed, and adjustable wiring methods are limited. Power flow transfer channels are often lacking, and even if transfer is possible, adjustments can lead to secondary risks such as increased system short-circuit current and overload of other equipment. Load shedding is primarily based on summer load estimates, which reduces grid reliability and increases outage duration. Disconnecting generators damages batteries, and rapid start-up and shutdown affect generator stability, thus impacting grid stability. Manual adjustment of energy storage power relies on manual operation; small adjustments cannot quickly eliminate equipment overload, while large adjustments compress the continuous charging and discharging time, leaving insufficient time for mode adjustments. Therefore, current methods using automatic safety devices for overcurrent control after fault elimination result in low power supply reliability and stability, and poor adjustment stability. Summary of the Invention

[0005] This application provides a control method and system for energy storage devices based on sensitivity analysis, in order to solve the problems of low power supply reliability and stability, and poor adjustment stability in existing control methods.

[0006] To address the aforementioned technical problems, the embodiments of this application disclose the following technical solutions:

[0007] A control method for an energy storage device based on sensitivity analysis, wherein the energy storage device is used to transfer power flow to corresponding equipment in a power grid system, the method comprising:

[0008] When any device in the power grid system is overloaded, the energy storage device is determined to be consistent with the required energy storage state based on the energy storage charging and discharging state required to eliminate the overload of the device and the current energy state of the energy storage device.

[0009] If so, the energy storage charging and discharging power is tuned online using sensitivity analysis to determine the optimal control quantity. Once the energy storage device meets the set conditions for eliminating equipment overload, the first control strategy is sent to the stabilization and control device matched with any device. The first control strategy is an online control strategy, and each device is matched with one stabilization and control device.

[0010] If not, the second control strategy is adopted and the second control strategy is sent to the stabilization and control device matched with any of the devices. The second control strategy is an offline control strategy.

[0011] When any of the devices meets the set start-up conditions, the stabilization device matched with any of the devices executes the first control strategy or the second control strategy.

[0012] Optionally, when any device in the power grid system experiences an overload, before determining whether the energy storage device matches the required energy storage state based on the energy storage charging / discharging state needed to eliminate the overload of the device and the current energy state of the energy storage device, the method further includes:

[0013] Collect the real-time current value of any device in the power grid system;

[0014] Determine whether the real-time current value is greater than the set current value;

[0015] If so, determine that any of the devices is overloaded; otherwise, determine that any of the devices is not overloaded.

[0016] Optionally, a method for determining whether the energy storage device matches the required energy storage state based on the energy storage charge / discharge state needed to eliminate the overload of any of the devices and the current energy state of the energy storage device includes:

[0017] When the energy storage charging / discharging state required to eliminate the overload of any of the devices is charging, determine whether the current energy storage device's energy capacity is ≥ 90% of the energy storage device's maximum stored energy capacity;

[0018] If so, it is determined that the energy storage device is inconsistent with the required energy storage state;

[0019] If not, the energy storage device is determined to be consistent with the required energy storage state;

[0020] When the energy storage charging / discharging state required to eliminate the overload of any of the devices is discharging, determine whether the current energy storage device's energy capacity is ≤ 10% of the maximum energy storage capacity of the energy storage device;

[0021] If so, it is determined that the energy storage device is inconsistent with the energy storage state;

[0022] If not, the energy storage device is determined to be consistent with the required energy storage state.

[0023] Optionally, a method for determining the optimal control quantity by using sensitivity analysis to online tune the energy storage charging and discharging power includes:

[0024] Based on the device current value and the device rated current value, an objective function for online tuning of energy storage charging and discharging power is constructed based on sensitivity, and constraints are set according to the maximum rechargeable and maximum dischargeable values ​​of the energy storage device.

[0025] The initial search value of the objective function is determined by offline tuning.

[0026] Based on the device current value, the initial search value, and the constraints, the search control quantity and sensitivity of the energy storage device are iterated multiple times until the objective function converges. The control quantity obtained in the last search is taken as the optimal control quantity of the energy storage device.

[0027] Optionally, determining the initial search value of the objective function using offline tuning includes:

[0028] Multiple typical historical load sections were selected to scan the switching elements that caused overcurrent in any of the devices.

[0029] Adjust the charging and discharging capacity of the energy storage device according to the scan results until the current value of any device is less than 85% of the rated current value.

[0030] The current value of any device is divided into several levels, and the maximum charge and discharge capacity of the energy storage device corresponding to the current value of each level is used as the corresponding initial search value.

[0031] Optionally, the method of iterating the search control quantity and sensitivity of the energy storage device multiple times based on the device current value, the initial search value, and the constraints until the objective function converges, and using the control quantity at which the objective function converges as the optimal control quantity of the energy storage device, includes:

[0032] Based on the device current value and the initial search value of the control quantity, the device current value is obtained through simulation.

[0033] Determine whether the previous control quantity of any of the devices satisfies the constraint conditions;

[0034] If so, based on the previous control variable, use the formula The corresponding sensitivity was calculated and then used using the formula. Estimate the limits of the control parameters, where, The sensitivity of the current tidal current section, , , These represent the previous device current value, the current device current value, and the next device current value, respectively. , , These are the previous control quantity, the current control quantity, and the next control quantity for the energy storage device, respectively.

[0035] Substitute the control parameter limits into the current power flow section for numerical simulation to calculate the current current value of any device.

[0036] Determine whether the current device current value of any of the devices conforms to the objective function. ,in, For the error limit;

[0037] If so, the control parameter limit obtained from the last search is taken as the optimal control quantity for the energy storage device;

[0038] If not, return to re-evaluate whether the next control quantity of any device satisfies the constraint conditions, until the objective function converges.

[0039] Optionally, the set conditions for eliminating equipment overload include:

[0040] The adjusted charging and discharging power of the energy storage device is less than the maximum charging and discharging power of the energy storage device; and,

[0041] The charging and discharging duration of the energy storage device is longer than the minimum adjustment time of the power grid operation mode.

[0042] Optionally, the set activation conditions include:

[0043] The starting element has a current greater than the overload starting current setting value, and the starting time is greater than the overload starting delay. The starting element is located in the energy storage device.

[0044] Optionally, when multiple devices are overloaded and require the energy storage device, the energy storage device is called one by one according to the order in which the devices are overloaded, and only one device can call the energy storage device at any given time.

[0045] A sensitivity analysis-based control system for an energy storage device, wherein the energy storage device is used to transfer power flow to corresponding equipment in a power grid system, the system comprising:

[0046] The energy storage status judgment module is used to determine whether the energy storage device is consistent with the required energy storage status when any device in the power grid system is overloaded, based on the energy storage charging and discharging status required to eliminate the overload of the device and the current power status of the energy storage device.

[0047] The online control module is used to perform online tuning of the energy storage charging and discharging power using a sensitivity analysis method when the energy storage device is consistent with the required energy storage state, to determine the optimal control quantity, and to issue a first control strategy to the stabilization control device matched by any device after the energy storage device meets the set conditions for eliminating equipment overload. The first control strategy is an online control strategy, and each device is matched with one stabilization control device.

[0048] An offline control module is used to adopt a second control strategy when the energy storage device is inconsistent with the required energy storage state, and to send the second control strategy to the stabilization and control device matched with any of the devices. The second control strategy is an offline control strategy.

[0049] The stabilization device is used to execute the first control strategy or the second control strategy when it detects that any of the devices meets the set start-up conditions.

[0050] The technical solutions provided by the embodiments of this application may include the following beneficial effects:

[0051] This application provides a control method for energy storage devices based on sensitivity analysis. When any device experiences overload, the method first determines whether the energy storage device matches the required energy storage charging / discharging state and the current energy state of the energy storage device, based on the energy storage charging / discharging state needed to eliminate the overload. If they match, sensitivity analysis is used to adjust the energy storage charging / discharging power online to determine the optimal control quantity. This process continues until the energy storage device meets the set overload elimination conditions. Then, an online control strategy is sent to the matching stability control device for any device. If they do not match, a second control strategy is sent to the stability control device. Finally, when the device meets the startup conditions, the stability control device executes the corresponding control strategy. This embodiment utilizes the rapid charging / discharging function of the energy storage device to replace the grid connection adjustment, load shedding, and generator shedding measures in the prior art. This allows for rapid power flow transfer without affecting load and generation power, effectively improving the reliability and stability of power consumption. Furthermore, this embodiment uses sensitivity analysis to adjust the energy storage charging / discharging power online, quickly determining the optimal control quantity and allowing sufficient time for grid connection adjustments while ensuring overload elimination. Moreover, this embodiment adopts different control strategies for different situations, making the control of the stabilization device more flexible, avoiding over-adjustment and pre-adjustment, and ultimately achieving optimal control of the energy storage device's control quantity.

[0052] This application also provides a sensitivity analysis-based energy storage device control system. This system mainly includes an energy storage state judgment module, an online control module, an offline control module, and a stabilization control device. The energy storage state judgment module determines whether the current energy storage state of the energy storage device matches the required energy storage state. Based on the judgment result, it determines whether to activate the online or offline control module, thereby obtaining different control strategies. Finally, the stabilization control device executes the corresponding control strategy according to the activation conditions. This embodiment achieves rapid power flow transfer without affecting load and power generation by controlling the energy storage device, thus effectively improving the reliability and stability of power consumption. The online control module utilizes sensitivity analysis for online tuning of energy storage charging and discharging power, enabling rapid acquisition of optimal control quantities and allowing sufficient time for grid regulation, which is beneficial for improving the stability and efficiency of regulation.

[0053] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0054] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0055] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0056] Figure 1 A schematic flowchart illustrating a sensitivity analysis-based energy storage device control method provided in an embodiment of this application;

[0057] Figure 2 This is a schematic diagram illustrating the principle of the energy storage device control method based on sensitivity analysis in the embodiments of this application;

[0058] Figure 3 This is a schematic diagram illustrating the principle of the device overload judgment process in the embodiments of this application;

[0059] Figure 4 This is a flowchart illustrating the method for determining the optimal control quantity of an energy storage device in an embodiment of this application.

[0060] Figure 5 A schematic diagram of a control system for an energy storage device based on sensitivity analysis, provided as an embodiment of this application;

[0061] Figure 6 This is a schematic diagram illustrating the working principle of the energy storage device control system based on sensitivity analysis in the embodiments of this application. Detailed Implementation

[0062] To enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of this application.

[0063] To better understand this application, the embodiments of this application will be explained in detail below with reference to the accompanying drawings.

[0064] Example 1

[0065] See Figure 1 ,Depend on Figure 1 As can be seen, the energy storage device control method based on sensitivity analysis in this embodiment mainly includes the following processes:

[0066] S1: When any device in the power grid system is overloaded, determine whether the energy storage device is consistent with the required energy storage state based on the energy storage charging and discharging state required to eliminate the overload of any device and the current energy state of the energy storage device.

[0067] This embodiment utilizes an energy storage device to replace various methods in the prior art. Based on the rapid charging and discharging capability of the energy storage device, it achieves rapid power flow transfer without affecting the load and power generation. When starting the energy storage device, it is first necessary to determine whether the energy storage device is consistent with the required energy storage state. Specifically, this is determined from two aspects: the current power state of the energy storage device and the charging / discharging state required to eliminate overload (charging or discharging). Specifically, step S1 includes the following process:

[0068] S11: When the energy storage charging / discharging state required to eliminate any device overload is charging, determine whether the current energy of the energy storage device is ≥ 90% of the maximum energy storage capacity of the energy storage device.

[0069] If the current power of the energy storage device is greater than or equal to 90% of the maximum storage capacity of the energy storage device, it means that the energy storage device cannot continue to charge, and step S12 is executed: determine that the energy storage device is inconsistent with the required energy storage state.

[0070] If the current power of the energy storage device is less than 90% of the maximum storage capacity of the energy storage device, it means that the energy storage device can continue to be charged, and step S13 is executed: determine that the energy storage device is consistent with the required energy storage state.

[0071] S14: When the energy storage charging / discharging state required to eliminate any device overload is discharging, determine whether the current energy storage device's current energy capacity is ≤ 10% of the energy storage device's maximum storage capacity.

[0072] If the current power of the energy storage device is less than or equal to 10% of the maximum storage capacity of the energy storage device, it is determined that the energy storage device cannot continue to discharge, and step S15 is executed: determine that the energy storage device and the energy storage state are inconsistent.

[0073] If the current power of the energy storage device is greater than 10% of the maximum storage capacity of the energy storage device, it is determined that the energy storage device can continue to discharge, and step S16 is executed: determine that the energy storage device is consistent with the required energy storage state.

[0074] Furthermore, this embodiment also includes a process for determining whether a device is overloaded. The overload determination method can use current or power to determine if an overload has occurred. Specifically, using the current method, firstly, the real-time current value of any device in the power grid system is collected. This can be done using a current transformer (CT). Then, it is determined whether the real-time current value is greater than a set current value. If it is, the device is determined to be overloaded; otherwise, it is determined that the device is not overloaded. The process ends when there is no overload.

[0075] It can independently determine overload alarms, overload starts, and overload actions. Each overload action is determined independently, without any sequential relationship. However, the action's exit condition must be logically ANDed with the overload start condition to exit. See [link to documentation] for details. Figure 3 As shown, multiple rounds are employed, and so on. Since the energy storage device has millisecond-level power regulation capability, the first round of overload is achieved by regulating the energy storage power, while subsequent rounds can be achieved using traditional control measures such as tripping generators, shedding loads, and changing network topology. Figure 3 middle, This is the overload alarm current setting value. This is the overload starting current setting value. This is the overload operating current setting value for the first round. This is the overload operating current setting value for the second round. To delay the overload alarm, For overload start delay, Delay for the first round of overload action, Delay for the second round of overload action.

[0076] Once an overload is detected, continue with step S1.

[0077] If the energy storage device matches the required energy storage state, proceed to step S2: use sensitivity analysis to perform online tuning of the energy storage charging and discharging power, determine the optimal control quantity, and continue until the energy storage device meets the set conditions for eliminating equipment overload. Then, issue the first control strategy to the stabilization and control device matched with any device. The first control strategy is an online control strategy, and each device is matched with one stabilization and control device.

[0078] Specifically, the method of using sensitivity analysis to online tune the energy storage charging and discharging power and determine the optimal control quantity includes:

[0079] S21: Based on the device current value and the device rated current value, construct an objective function for online tuning of energy storage charging and discharging power based on sensitivity, and set constraints based on the maximum rechargeable and maximum dischargeable values ​​of the energy storage device.

[0080] This embodiment uses sensitivity information to search for the optimal control quantity of the energy storage device, and the objective function is: That is, the equipment current value of any device is approximately 0.85 times its rated current value. The constraint is: That is, the control parameters of the energy storage device are within the maximum charge / discharge range. Specifically, during discharge, Positive, during charging Negative, This is the maximum rechargeable value. This represents the maximum discharge value.

[0081] S22: Use offline tuning to determine the initial search value of the objective function.

[0082] The initial search value is the initial control value of the energy storage device. In this embodiment, the initial search value is determined by offline tuning, which enables the objective function to converge quickly, thereby improving the control efficiency of the energy storage device.

[0083] Specifically, step S22 includes the following process:

[0084] S221: Select multiple typical historical load sections and scan the switching elements that cause overcurrent in any equipment.

[0085] S222: Adjust the charging and discharging capacity of the energy storage device according to the scanning results until the current value of any device is less than 85% of the rated current value.

[0086] S223: Divide the current value of any device into several levels on average, and use the maximum charge and discharge capacity of the energy storage device corresponding to the current value of each level as the corresponding initial search value.

[0087] In this embodiment, the current value of any device is also called the device overcurrent value. The device current value can be divided into 5 levels on average, and the maximum charging and discharging capacity of the energy storage device corresponding to the corresponding level is selected. When the current value of the equipment is at a certain level, the maximum charge and discharge capacity of the matched energy storage device will be determined. As the initial control variable, see Table 1 below.

[0088]

[0089] Table 1. Correspondence between Equipment Overcurrent Values ​​and Energy Storage Device Control Quantities

[0090] S23: Based on the device current value, initial search value, and constraints, iterate the search control quantity and sensitivity of the energy storage device multiple times until the objective function converges. Use the control quantity obtained from the last search as the optimal control quantity of the energy storage device.

[0091] Specifically, step S23 can be found in [reference needed]. Figure 4 The flowchart shown is composed of... Figure 4 The steps to determine the optimal control quantity are as follows:

[0092] S231: Based on device current value Determine the initial search value Flow calculations are performed to obtain Let i = 0;

[0093] S232: Determine the control value quantity Does the constraint condition meet? If If the maximum charge / discharge range is exceeded, the energy storage device is considered unable to meet the requirements for eliminating equipment overload, and the search is terminated. Otherwise, proceed to step S233.

[0094] S233: Based on the previous control variable Calculate sensitivity Estimate the limits of control parameters .in, , .

[0095] S234: Limit the control parameters By substituting the current power flow profile into the numerical simulation, the current value of the equipment can be calculated. .

[0096] S235: Convergence check: If The result of the last search As the optimal control solution; otherwise, let Return to step S232.

[0097] See also Figure 1 It can be seen that if the energy storage device is inconsistent with the required energy storage state, step S3 is executed: the second control strategy is adopted and the second control strategy is sent to any device matching the stabilization and control device, wherein the second control strategy is an offline control strategy.

[0098] In other words, when the energy storage device is not in the required energy storage state, the traditional offline control strategy is adopted.

[0099] S4: When any device meets the set start-up conditions, the control device matched with any device executes the first control strategy or the second control strategy.

[0100] The startup conditions set in this embodiment include: the current of the startup element is greater than the overload startup current setting value, and the startup time is greater than the overload startup delay. The startup element is located within the energy storage device. After the startup element activates, the positive power supply to the output relay is turned on, and the startup of the software output modules is independent of each other. This startup method ensures reliable startup into the fault identification state under various power grid fault conditions, improving system reliability. Furthermore, it avoids frequent startups under normal operating conditions, thereby improving the stability of the entire power grid system.

[0101] When the energy storage device matches the required energy storage state, if the device meets the set startup conditions, the corresponding stability control device executes the first control strategy. When the energy storage device does not match the required energy storage state, if the device meets the set startup conditions, the corresponding stability control device executes the second control strategy.

[0102] Furthermore, in this embodiment, when multiple devices experience overload and need to simultaneously utilize the same energy storage device, the energy storage startup elements of other devices are locked after the overloaded device starts up. In other words, when the current device calls the energy storage device, other devices are locked out. This method prevents power fluctuations in the energy storage device, thereby ensuring its stability.

[0103] Example 2

[0104] exist Figures 1-4 Based on the illustrated embodiment, see also Figure 5 ,Depend on Figure 5 The system mainly includes: an energy storage status judgment module, an online control module, an offline control module, and a stabilization control device. The energy storage status judgment module determines whether the energy storage device matches the required energy storage charging / discharging state and the current energy level of the energy storage device when any device in the power grid experiences an overload. The online control module, when the energy storage device matches the required energy storage state, uses sensitivity analysis to adjust the energy storage charging / discharging power online to determine the optimal control quantity. Once the energy storage device meets the set overload elimination conditions, a first control strategy is sent to the stabilization control device matched to the device. This first control strategy is an online control strategy, and each device is matched with one stabilization control device. The offline control module, when the energy storage device does not match the required energy storage state, adopts a second control strategy and sends it to the stabilization control device matched to the device. This second control strategy is an offline control strategy. The stabilization control device executes either the first or second control strategy when it detects that any device meets the set start-up conditions.

[0105] Furthermore, the system also includes an overload detection module for determining whether any device in the power grid system is overloaded. This overload detection module further includes a current acquisition unit and a first detection unit. The current acquisition unit acquires the real-time current value of any device in the power grid system. The first detection unit determines whether the real-time current value is greater than a set current value; if so, the device is determined to be overloaded; otherwise, the device is determined not to be overloaded.

[0106] The energy storage status determination module includes a second determination unit and a third determination unit. The second determination unit, when the energy storage charging / discharging state required to eliminate any device overload is charging, determines whether the current energy level of the energy storage device is ≥ 90% of the maximum storage capacity of the energy storage device. If yes, it determines that the energy storage device is inconsistent with the required energy storage state; otherwise, it determines that the energy storage device is consistent with the required energy storage state. The third determination unit, when the energy storage charging / discharging state required to eliminate any device overload is discharging, determines whether the current energy level of the energy storage device is ≤ 10% of the maximum storage capacity of the energy storage device. If yes, it determines that the energy storage device is inconsistent with the energy storage state; otherwise, it determines that the energy storage device is consistent with the required energy storage state.

[0107] The working principle of the energy storage device control system based on sensitivity analysis in this embodiment can be found in [reference needed]. Figure 6 As shown. Figure 6 In the text, Y represents yes, and N represents no.

[0108] For details not described in this embodiment, please refer to [link / reference]. Figures 1-4 The embodiments shown are interchangeable and will not be described in detail here.

[0109] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A control method for an energy storage device based on sensitivity analysis, characterized in that, The energy storage device is used to transfer power flow to corresponding equipment in the power grid system, and the method includes: When any device in the power grid system is overloaded, the energy storage device is determined to be consistent with the required energy storage state based on the energy storage charging and discharging state required to eliminate the overload of the device and the current energy state of the energy storage device. If so, the energy storage charging and discharging power is tuned online using sensitivity analysis to determine the optimal control quantity. Once the energy storage device meets the set conditions for eliminating equipment overload, the first control strategy is sent to the stabilization and control device matched with any device. The first control strategy is an online control strategy, and each device is matched with one stabilization and control device. If not, the second control strategy is adopted and the second control strategy is sent to the stabilization and control device matched with any of the devices. The second control strategy is an offline control strategy. When any of the devices meets the set start-up conditions, the stabilization and control device matched with any of the devices executes the first control strategy or the second control strategy; A method for determining whether the energy storage device matches the required energy storage state based on the energy storage charge / discharge state needed to eliminate overload of any of the devices and the current energy state of the energy storage device includes: When the energy storage charging / discharging state required to eliminate the overload of any of the devices is charging, determine whether the current energy storage device's energy capacity is ≥ 90% of the energy storage device's maximum stored energy capacity; If so, it is determined that the energy storage device is inconsistent with the required energy storage state; If not, the energy storage device is determined to be consistent with the required energy storage state; When the energy storage charging / discharging state required to eliminate the overload of any of the devices is discharging, determine whether the current energy storage device's energy capacity is ≤ 10% of the maximum energy storage capacity of the energy storage device; If so, it is determined that the energy storage device is inconsistent with the energy storage state; If not, the energy storage device is determined to be consistent with the required energy storage state; Methods for determining the optimal control quantity by using sensitivity analysis to online tune the charging and discharging power of energy storage include: Based on the device current value and the device rated current value, an objective function for online tuning of energy storage charging and discharging power is constructed based on sensitivity, and constraints are set according to the maximum rechargeable and maximum dischargeable values ​​of the energy storage device. The initial search value of the objective function is determined by offline tuning. Based on the device current value, the initial search value, and the constraints, the search control quantity and sensitivity of the energy storage device are iterated multiple times until the objective function converges. The control quantity obtained in the last search is taken as the optimal control quantity of the energy storage device.

2. The energy storage device control method based on sensitivity analysis according to claim 1, characterized in that, When any device in the power grid system experiences an overload, before determining whether the energy storage device matches the required energy storage state based on the energy storage charging / discharging state needed to eliminate the overload and the current energy state of the energy storage device, the method further includes: Collect the real-time current value of any device in the power grid system; Determine whether the real-time current value is greater than the set current value; If so, determine that any of the devices is overloaded; otherwise, determine that any of the devices is not overloaded.

3. The energy storage device control method based on sensitivity analysis according to claim 1, characterized in that, The method of determining the initial search value of the objective function using offline tuning includes: Multiple typical historical load sections were selected to scan the switching elements that caused overcurrent in any of the devices. Adjust the charging and discharging capacity of the energy storage device according to the scan results until the current value of any device is less than 85% of the rated current value. The current value of any device is divided into several levels, and the maximum charge and discharge capacity of the energy storage device corresponding to the current value of each level is used as the corresponding initial search value.

4. The energy storage device control method based on sensitivity analysis according to claim 1, characterized in that, The method involves iterating the search control quantity and sensitivity of the energy storage device multiple times based on the device current value, initial search value, and constraints until the objective function converges, and using the control quantity at which the objective function converges as the optimal control quantity for the energy storage device. This includes: Based on the device current value and the initial search value of the control quantity, the device current value is obtained through simulation. Determine whether the previous control quantity of any of the devices satisfies the constraint conditions; If so, based on the previous control variable, use the formula The corresponding sensitivity was calculated and then used using the formula. Estimate the limits of the control parameters, where, The sensitivity of the current tidal current section, , , These are the device current values ​​for the previous search process, the current search process, and the next search process, respectively. , , These are the energy storage device control quantities for the previous search process, the energy storage control quantities for the current search process, and the calculated energy storage device control quantities for the next search process, respectively. Substitute the control parameter limits into the current power flow section for numerical simulation to calculate the current current value of any device. Determine whether the current device current value of any of the devices conforms to the objective function. ,in, For the error limit, This is the rated current value; If so, the control parameter limit obtained from the last search is taken as the optimal control quantity for the energy storage device; If not, return to re-evaluate whether the next control quantity of any device satisfies the constraint conditions, until the objective function converges.

5. The energy storage device control method based on sensitivity analysis according to claim 1, characterized in that, The established conditions for eliminating equipment overload include: The adjusted charging and discharging power of the energy storage device is less than the maximum charging and discharging power of the energy storage device; and, The charging and discharging duration of the energy storage device is longer than the minimum adjustment time of the power grid operation mode.

6. The energy storage device control method based on sensitivity analysis according to claim 1, characterized in that, The set activation conditions include: The starting element has a current greater than the overload starting current setting value, and the starting time is greater than the overload starting delay. The starting element is located in the energy storage device.

7. The energy storage device control method based on sensitivity analysis according to claim 1, characterized in that, When multiple devices experience overload and require the energy storage device, the energy storage device is invoked one by one according to the order in which the devices experienced overload, and only one device invokes the energy storage device at any given time.

8. A control system for an energy storage device based on sensitivity analysis, characterized in that, The system is used to implement the method of claim 1, wherein the energy storage device is used to transfer the power flow of corresponding equipment in the power grid system, and the system comprises: The energy storage status judgment module is used to determine whether the energy storage device is consistent with the required energy storage status when any device in the power grid system is overloaded, based on the energy storage charging and discharging status required to eliminate the overload of the device and the current power status of the energy storage device. The online control module is used to perform online tuning of the energy storage charging and discharging power using a sensitivity analysis method when the energy storage device is consistent with the required energy storage state, to determine the optimal control quantity, and to issue a first control strategy to the stabilization control device matched by any device after the energy storage device meets the set conditions for eliminating equipment overload. The first control strategy is an online control strategy, and each device is matched with one stabilization control device. An offline control module is used to adopt a second control strategy when the energy storage device is inconsistent with the required energy storage state, and to send the second control strategy to the stabilization and control device matched with any of the devices. The second control strategy is an offline control strategy. The stabilization device is used to execute the first control strategy or the second control strategy when it detects that any of the devices meets the set start-up conditions.

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