Low-voltage area hierarchical energy storage control method and device for new energy consumption

Abstract

The application discloses a low-voltage transformer area layered energy storage control method and device for new energy consumption, and relates to the field of power system control. The low-voltage transformer area layered energy storage control method for new energy consumption comprises the following steps: single-phase energy storage devices are arranged in A, B and C single-phase lines of a low-voltage transformer area, and three-phase energy storage devices are arranged in three-phase load lines; load power and new energy output of each line are collected, and discharge demand and charging demand of each line under each risk scenario are calculated; local discharge demand and local charging demand of the single-phase energy storage devices and the three-phase energy storage devices are calculated according to the discharge demand and the charging demand under each risk scenario; rated power and rated capacity of the single-phase energy storage devices and the three-phase energy storage devices are determined according to the local discharge demand and the local charging demand; operation state data of the low-voltage transformer area are collected, and a line position and a risk type existing in the line are determined; and the corresponding energy storage devices are controlled to operate according to the line position and the risk type.

Description

Technical Field

[0001] This application relates to the field of power system control, and in particular to a method and device for stratified energy storage control in low-voltage substations for new energy consumption. Background Technology

[0002] The power system is gradually shifting from a traditional operating mode dominated by centralized power sources and unidirectional power supply to a new power system mode characterized by high proportion of renewable energy integration, coordinated interaction between power generation, grid, load and storage, and flexible adjustment of the distribution network.

[0003] In actual development, the rapid growth of distributed photovoltaic, distributed wind power, electric vehicle charging facilities, residential air conditioning loads, and various low-voltage three-phase user loads has gradually transformed low-voltage distribution areas from the traditional "one-way power supply from the upper-level grid to the user" model to a complex operating mode characterized by "local access to new energy sources, random load fluctuations, bidirectional power flow, and multiple risks." These changes have led to more complex issues for low-voltage distribution areas, including new energy absorption, reverse power flow, peak loads, three-phase imbalance, and voltage exceeding limits, placing higher demands on the flexible resource adjustment and tiered management capabilities of the distribution areas.

[0004] At the low-voltage distribution area level, distributed renewable energy and load access exhibit significant spatial dispersion and phase imbalance characteristics. The load size, electricity consumption behavior, renewable energy access location, and output characteristics of the three single-phase lines A, B, and C may differ, leading to severe overload, reverse severe overload, high / low voltage, or three-phase imbalance in one phase, while other lines remain normal. Three-phase load lines typically serve public services, commercial users, or low-voltage three-phase users, and their operational risks differ from those of residential single-phase lines. Therefore, low-voltage distribution area risks manifest not only as overall limit exceedances at the transformer outlet or low-voltage busbar level but also as local limit exceedances in single-phase lines or three-phase load lines.

[0005] With the growth of distributed photovoltaic, distributed wind power, and electric vehicle charging loads, low-voltage distribution areas are more prone to bidirectional power flow and localized safety issues: when renewable energy output is high and load is low, reverse power flow, high voltage, and limited renewable energy absorption may occur; during evening peak hours, summer air conditioning peak hours, or when charging loads are concentrated, heavy overload and low voltage may occur; uneven distribution of load and renewable energy phases may also exacerbate three-phase imbalance. New energy storage technologies possess bidirectional charging and discharging regulation capabilities, which can be used to reduce heavy overload, absorb excess renewable energy power, suppress reverse power flow, support voltage, and improve three-phase imbalance. However, if energy storage is only used as a centralized regulation resource at the distribution area outlet or low-voltage busbar, although it can regulate the overall power of the distribution area, it is difficult to directly address the localized risks of single-phase lines (A / B / C) or three-phase load lines. When a line experiences a localized overload, the overall power of the distribution area may not yet exceed the limit, making it difficult for centralized energy storage to provide timely and accurate on-site management of that line. Summary of the Invention

[0006] This application provides a method and device for layered energy storage control in low-voltage distribution areas for new energy consumption, realizing the transformation of low-voltage distribution area energy storage from "centralized regulation of the entire distribution area" to "layered configuration, on-site treatment, and overall coordination".

[0007] In a first aspect, this application provides a low-voltage, stratified energy storage control method for renewable energy integration, comprising: Single-phase energy storage devices are installed in the single-phase lines A, B, and C of the low-voltage distribution area, and three-phase energy storage devices are installed in the three-phase load lines. Collect the load power and renewable energy output of each single-phase line and three-phase load line, and calculate the discharge and charging requirements of each single-phase line and three-phase load line under various risk scenarios based on the load power and renewable energy output. Calculate the partial discharge and partial charging requirements of single-phase and three-phase energy storage devices based on the discharge and charging requirements under various risk scenarios. The rated power and rated capacity of single-phase and three-phase energy storage devices are determined based on their partial discharge and partial charging requirements. Collect operational status data of low-voltage distribution areas, and determine the location of lines with risks and the type of risks based on the operational status data; The operation of the corresponding energy storage device is controlled according to the location of the line and the type of risk.

[0008] Specifically, the calculation of discharge and charging demands for each single-phase and three-phase load line under various risk scenarios based on load power and renewable energy output includes: The net power, power in the direction of power purchase, power in the direction of power transmission, and surplus power of new energy are calculated by using the load power of a single-phase line and the output of new energy sources. Based on net power, power in the direction of power purchase, power in the direction of reverse power transmission, and surplus power of renewable energy, determine the heavy overload discharge demand, reverse heavy overload charging demand, renewable energy consumption charging demand, low voltage discharge demand, and high voltage charging demand of each single-phase line under risk scenarios of heavy overload, reverse heavy overload, renewable energy surplus, high and low voltage, and three-phase imbalance, as well as the single-phase energy storage discharge demand and single-phase energy storage charging demand caused by three-phase imbalance, and the heavy overload discharge demand, reverse heavy overload charging demand, renewable energy consumption charging demand, low voltage discharge demand, and high voltage charging demand of three-phase load lines.

[0009] Specifically, the calculation of partial discharge and partial charging requirements for single-phase and three-phase energy storage devices based on discharge and charging requirements under various risk scenarios includes: The partial discharge requirement for a single-phase energy storage device is:

[0010] in, To meet the heavy overload discharge requirements of single-phase lines, This is to address the single-phase energy storage discharge demand caused by the three-phase imbalance in a single-phase circuit. To meet the low-voltage discharge requirements of single-phase lines; The partial discharge requirement for a single-phase energy storage device is:

[0011] To meet the reverse overload charging requirements of single-phase lines, To meet the charging needs of new energy consumption on single-phase lines. This addresses the single-phase energy storage charging demand caused by the three-phase imbalance in a single-phase circuit. To meet the high-voltage charging needs of single-phase lines; The partial discharge requirement for three-phase energy storage devices is:

[0012] These are the heavy overload discharge requirements and low voltage discharge requirements for three-phase load lines, respectively. The partial charging demand of three-phase energy storage devices is as follows:

[0013] These are respectively the reverse overload charging demand of three-phase load lines, the charging demand for new energy consumption, and the high-voltage charging demand.

[0014] Specifically, determining the rated power and rated capacity of the single-phase energy storage device and the three-phase energy storage device based on their partial discharge and partial charging requirements includes: For each energy storage device in a single-phase energy storage device and a three-phase energy storage device, the maximum partial discharge demand and the maximum partial charge demand of the energy storage device are determined based on the partial discharge demand and the partial charge demand of the energy storage device. The rated power of the energy storage device is determined by the maximum partial discharge demand and the maximum partial charge demand. Obtain the discharge efficiency and charging efficiency of the energy storage device; Based on the discharge efficiency and charging efficiency of the energy storage device, as well as the partial discharge demand and partial charging demand of the energy storage device, determine the partial discharge energy, partial charging absorption energy, and new energy consumption energy of the energy storage device. Obtain the preset upper limit of SOC, lower limit of SOC, discharge SOC ratio, charging SOC ratio, and reserved SOC space ratio of the energy storage device, and determine the rated capacity of the energy storage device using the following formula:

[0015] in, For partial discharge energy, Absorb energy for local charging, Energy is absorbed by new energy sources; This refers to the discharge SOC ratio. This refers to the charging SOC ratio. To reserve a certain proportion of SOC space.

[0016] Specifically, the collection of operational status data for the low-voltage distribution area includes: The system collects voltage, current, power direction, renewable energy output, and load power data for single-phase lines, three-phase load lines, and transformer outlets in low-voltage distribution areas A, B, and C. It also collects SOC, dischargeable power, rechargeable power, and energy storage access switch status data for single-phase and three-phase energy storage devices to obtain operational status data.

[0017] Specifically, determining the location and type of risk based on operational status data includes: Calculate the net power, power in the direction of power purchase, power in the direction of reverse power transmission, and surplus power of new energy for any single-phase line or three-phase load line based on the operating status data. The risk indicator variables for each risk type of the line are determined based on net power, power purchased in the direction of power, power transmitted in the direction of power, and surplus power of new energy sources. These risk indicator variables are used to indicate whether there is a risk. Calculate the overall net power of the transformer area, the overall power in the direction of power purchase of the transformer area, and the overall power in the direction of power transmission of the transformer area based on the operating status data. The risk indicator variables for the entire transformer substation are determined based on the overall net power of the substation, the overall power purchased by the substation, and the overall power transmitted back to the substation.

[0018] Specifically, controlling the operation of the corresponding energy storage device based on the line location and risk type includes: If the line location is any single-phase line A, B, or C, the operating mode of the single-phase energy storage device corresponding to the single-phase line is determined based on the risk indicator variable indicating the risk, and the single-phase energy storage device is called to operate according to the operating mode. If the line location is a three-phase load line, the operating mode of the three-phase energy storage device is determined according to the risk indicator variables, and the three-phase energy storage device is called to operate according to the operating mode. If the line location is at the transformer substation exit, the target energy storage device is selected from single-phase and three-phase energy storage devices according to the operating mode corresponding to the risk indicator variable, and the target energy storage device is called to operate.

[0019] Furthermore, the above method also includes: When the operating mode of a single-phase energy storage device or a three-phase energy storage device is discharge, the energy storage discharge power command is:

[0020] To call up the operating energy storage device Rated power, For routes with risks The partial discharge requirement, For energy storage devices The dischargeable power; When the operating mode of a single-phase energy storage device or a three-phase energy storage device is charging, the energy storage charging power command is:

[0021] The rechargeable power of the energy storage device ES. For routes with risks Localized charging needs.

[0022] Specifically, the step of selecting target energy storage devices from single-phase and three-phase energy storage devices based on the operating modes corresponding to risk indicator variables includes: If the risk indicator variable for overall overload in the transformer area is 1, then target energy storage devices are selected from the following set in descending order of State of Charge (SOC) and dischargeable power:

[0023] in For the set of routes, This represents a three-phase load line, where A, B, and C are single-phase lines (phase A, phase B, and phase C), respectively, and i represents any line. Let i be the current SOC of the energy storage device. For the energy storage device corresponding to line i The lower limit of SOC, For energy storage devices Dischargeable power, The energy storage access switch is in the current state. Indicates energy storage device The corresponding line has been connected. This indicates that the energy storage device is not connected. The discharge command for the selected target energy storage device satisfies:

[0024] If the risk indicator variable for the overall reverse heavy overload of the transformer area is 1, then target energy storage devices are selected according to the method of SOC from low to high and rechargeable power from high to low:

[0025] For the energy storage device corresponding to line i SOC upper limit; The charging command for the selected target energy storage device satisfies:

[0026] Update the SOC after executing the discharge or charge command.

[0027] Secondly, this application provides a low-voltage, tiered energy storage control device for renewable energy consumption, comprising: The energy storage tiered configuration module is used to configure single-phase energy storage devices in the A, B, and C single-phase lines of the low-voltage distribution area, and to configure three-phase energy storage devices in the three-phase load lines. The charging and discharging demand calculation module is used to collect the load power and renewable energy output of each single-phase line and three-phase load line, and calculate the discharging and charging demand of each single-phase line and three-phase load line under various risk scenarios based on the load power and renewable energy output. The risk demand calculation module is used to calculate the partial discharge and partial charging demands of single-phase and three-phase energy storage devices based on the discharge and charging demands under various risk scenarios. The energy storage power capacity determination module is used to determine the rated power and rated capacity of single-phase energy storage devices and three-phase energy storage devices based on their partial discharge and partial charging requirements. The risk identification module is used to collect the operating status data of low-voltage distribution areas and determine the location of lines with risks and the type of risks based on the operating status data. The switching control decision module is used to control the operation of the corresponding energy storage device based on the line location and risk type.

[0028] Thirdly, this application provides an electronic device including a memory and one or more processors. The memory stores one or more computer programs, each including instructions. When executed by the processor, the instructions cause the electronic device to perform the low-voltage tiered energy storage control method for renewable energy consumption as described in the first aspect.

[0029] Fourthly, this application provides a computer-readable storage medium storing instructions that, when executed on an electronic device, cause the electronic device to perform the low-voltage tiered energy storage control method for new energy consumption as described in the first aspect.

[0030] Fifthly, this application provides a computer program product that, when run on an electronic device, causes the electronic device to execute the low-voltage tiered energy storage control method for new energy consumption as described in the first aspect.

[0031] Understandably, the beneficial effects that the aforementioned low-voltage stratified energy storage control method, device, electronic equipment, computer-readable storage medium, and computer program product for new energy consumption can achieve are as follows: By establishing a hierarchical energy storage configuration structure that distinguishes between single-phase lines and three-phase load lines, corresponding single-phase energy storage is configured at the beginning of single-phase lines A / B / C, and three-phase energy storage is configured at the beginning of three-phase load lines. This ensures that the location of the energy storage devices corresponds to the internal line structure of the low-voltage distribution area, avoiding the problem that a single centralized energy storage system cannot cover local line risks. Risk scenarios such as heavy overload, reverse power flow exceeding limits, renewable energy surplus, voltage exceeding limits, and three-phase imbalance of single-phase and three-phase load lines are converted into energy storage charging and discharging demands. The rated power of the energy storage is determined based on the maximum instantaneous demand, and the rated capacity of the energy storage is determined based on the cumulative energy demand during continuous risk periods and continuous renewable energy surplus periods, improving the targeting and rationality of energy storage configuration. By periodically collecting operational status data such as electrical parameters of each line, load power, renewable energy output, energy storage status, and connection switch status by the substation controller, operational risks are classified into local risks of single-phase lines, local risks of three-phase load lines, and overall risks of the substation. Furthermore, discharge support risks and charging absorption risks are distinguished, providing a clear basis for energy storage control actions. Through the hierarchical configuration and switching control of energy storage, energy storage can simultaneously participate in heavy overload reduction, reverse power flow suppression, renewable energy surplus absorption, voltage support, and three-phase imbalance improvement, thereby enhancing the comprehensive capabilities of low-voltage substation renewable energy consumption and safety management. Attached Figure Description

[0032] Figure 1 A schematic flowchart of a low-voltage tiered energy storage control method for new energy consumption provided in an embodiment of this application; Figure 2 A schematic diagram of the energy storage device in the low-voltage tiered energy storage control method for new energy consumption provided in the embodiments of this application; Figure 3 This is a schematic diagram of the system architecture of the low-voltage tiered energy storage control method for new energy consumption provided in the embodiments of this application. Detailed Implementation

[0033] To facilitate a clear description of the technical solutions in the embodiments of this application, the terms "first" and "second" are used in the embodiments of this application to distinguish identical or similar items with substantially the same function and effect. For example, "first chip" and "second chip" are only used to distinguish different chips and do not limit their order. Those skilled in the art will understand that the terms "first" and "second" do not limit the quantity or execution order, and the terms "first" and "second" do not necessarily imply that they are different. It should be noted that in the embodiments of this application, the words "exemplary" or "for example" are used to indicate that they are examples, illustrations, or descriptions. Any embodiment or design scheme described as "exemplary" or "for example" in this application should not be construed as being better or more advantageous than other embodiments or design schemes. Specifically, the use of the words "exemplary" or "for example" is intended to present the relevant concepts in a specific manner. In the embodiments of this application, "at least one" means one or more, and "more than one" means two or more.

[0034] It should be noted that "at the time of..." in the embodiments of this application can be either at the instant when a certain situation occurs, or for a period of time after the occurrence of a certain situation. The embodiments of this application do not make specific limitations on this.

[0035] The implementation of this embodiment will now be described in detail with reference to the accompanying drawings.

[0036] This embodiment provides a tiered energy storage control method for low-voltage distribution substations oriented towards renewable energy integration, applicable to low-voltage distribution substations with renewable energy access such as distributed photovoltaic and distributed wind power. This method focuses on the single-phase lines, three-phase load lines, and the overall operating status of the substation within the low-voltage substation. Through tiered energy storage configuration and operation switching control, it addresses issues such as line overload, reverse overload, voltage exceeding limits, three-phase imbalance, and renewable energy surplus.

[0037] For example, this low-voltage tiered energy storage control method for new energy consumption can be applied to various electronic devices such as computers (PCs), tablets, virtual reality / augmented reality devices, wearable devices, industrial computers, and vehicle systems; it can also be applied to servers, cloud computing, server clusters, etc., and this embodiment does not impose any special limitations on it.

[0038] Figure 1 A schematic flowchart of a low-voltage tiered energy storage control method for new energy consumption provided in an embodiment of this application is shown.

[0039] like Figure 1 As shown, the low-voltage tiered energy storage control method for new energy consumption can include the following steps: Step 101: Configure single-phase energy storage devices in the single-phase lines A, B, and C of the low-voltage distribution area, and configure three-phase energy storage devices in the three-phase load lines.

[0040] In this embodiment, a hierarchical configuration object and local risk demand model for energy storage at the head end of single-phase and three-phase lines are constructed, and a hierarchical configuration architecture of "single-phase energy storage corresponds to single-phase lines and three-phase energy storage corresponds to three-phase lines" is established: single-phase energy storage devices are configured at the head end of single-phase load lines of phases A, B, and C in the low-voltage distribution area, and three-phase energy storage devices are configured at the head end of three-phase load lines.

[0041] Energy storage device configuration such as Figure 2 As shown, the low-voltage distribution area includes a distribution transformer, a low-voltage busbar, a single-phase load line (A phase), a single-phase load line (B phase), a single-phase load line (C phase), and a three-phase load line; the A phase single-phase line is equipped with a single-phase energy storage device at its starting end. The B-phase single-phase line is equipped with B-phase single-phase energy storage at its starting end. The C-phase single-phase line is equipped with C-phase single-phase energy storage at its starting end. Three-phase energy storage is configured at the beginning of the three-phase load line. Each energy storage device is connected in parallel to the beginning of its corresponding line via an energy storage access switch. The energy storage access switch is used to control the connection or disconnection of the energy storage device from its corresponding line, but is not used to cut off the power supply to the main line.

[0042] In this embodiment, the energy storage configuration includes three single-phase lines A, B, and C, as well as a three-phase load line. The energy storage devices include single-phase energy storage devices configured at the beginning of the three single-phase lines A, B, and C, and three-phase energy storage devices configured at the beginning of the three-phase load line.

[0043] Define the set of three single-phase lines A, B, and C as follows:

[0044] Define the complete set of energy storage configuration lines as:

[0045] in, Indicates a three-phase load line; Indicates any energy storage configuration line that satisfies ; Describe any single-phase line that satisfies .definition To configure on the line The energy storage device at the head end, Corresponding to a single-phase A circuit, Corresponding to a single-phase B-phase line, Corresponding to a single-phase C-phase line, Corresponding to three-phase load lines.

[0046] Step 102: Collect the load power and renewable energy output of each single-phase line and three-phase load line, and calculate the discharge and charging requirements of each single-phase line and three-phase load line under each risk scenario based on the load power and renewable energy output.

[0047] Step 103: Calculate the partial discharge and partial charging requirements of single-phase and three-phase energy storage devices based on the discharge and charging requirements under each risk scenario.

[0048] After completing the topology construction of the low-voltage substation stratified energy storage configuration, the operating status of each line is converted into the partial charging and discharging requirements of the corresponding energy storage devices. The local risk requirements for safety management and new energy consumption for each line are calculated separately, resulting in the partial discharge and partial charging requirements of each energy storage device.

[0049] Specifically, the net power, power in the direction of power purchase, power in the direction of power transmission, and surplus power of renewable energy of a single-phase line are calculated using the load power and renewable energy output of the single-phase line. Based on the net power, power in the direction of power purchase, power in the direction of power transmission, and surplus power of renewable energy, the following are determined for each single-phase line under risk scenarios of heavy overload, reverse heavy overload, renewable energy surplus, high and low voltage, and three-phase imbalance: heavy overload discharge demand, reverse heavy overload charging demand, renewable energy consumption charging demand, low voltage discharge demand, high voltage charging demand, single-phase energy storage discharge demand and single-phase energy storage charging demand caused by three-phase imbalance, as well as the heavy overload discharge demand, reverse heavy overload charging demand, renewable energy consumption charging demand, low voltage discharge demand, and high voltage charging demand of the three-phase load line.

[0050] First, the net power of the line, the power in the direction of power purchase, the power in the direction of reverse transmission, and the surplus power of new energy are calculated based on the line load power and the output of new energy sources. Second, the discharge support demand or charging absorption demand corresponding to line overload, reverse power exceeding the limit, surplus new energy, voltage exceeding the limit, and three-phase imbalance are calculated respectively. Finally, the various risk demands are summarized to obtain the partial discharge demand and partial charging demand of each single-phase energy storage and three-phase energy storage. The correspondence between energy storage devices and risk scenarios is shown in Table 1.

[0051]

[0052] In this implementation, the risk types mainly include heavy overload, reverse heavy overload, surplus renewable energy, high / low voltage, and three-phase imbalance. The demand of each single-phase line and three-phase line under each risk scenario is calculated, as well as the demand of the three-phase load line under the risk scenario.

[0053] Specifically, define It is a collection of typical operating scenarios and risk scenarios. For scene indexing; define For discrete time periods, For time period index; defined This is the time interval between two adjacent time periods. For any line... ,definition For the line In risk scenarios Time period The load power under the definition For the line In the scene Time period The new energy output is underway. If the line... Without access to new energy sources, then... .

[0054] After collecting the load power of a single-phase line and the output of new energy sources, the following calculations are performed: line The net power is:

[0055] line The power consumption for the electricity purchase direction is:

[0056] line The reverse power is:

[0057] line The surplus power of new energy sources is:

[0058] Among them, when When, it indicates the line Absorb power from the low-voltage bus; when When, it indicates the line Power is fed back to the low-voltage bus or the upstream power grid.

[0059] For any single-phase line ,definition Single-phase line The permissible capacity or equivalent safe capacity is defined. Single-phase line The safe load rate threshold. Single-phase line. The heavy overload discharge requirement is:

[0060] definition Single-phase line Maximum permissible reverse power, single-phase line The reverse direction (reverse) heavy overload charging demand is:

[0061] definition Single-phase lines in the calculation of new energy consumption Permissible reverse power for single-phase lines The demand for new energy charging is as follows:

[0062] When backfeeding to the upper-level power grid is not permitted, it can be ordered At this time, all surplus power of new energy sources in the main phase line is given priority to be absorbed by the corresponding single-phase energy storage.

[0063] Furthermore, to characterize the degree of imbalance among the single-phase lines A, B, and C, the average net power of the three single-phase lines is defined as:

[0064] Define a single-phase line The deviation relative to the three-phase average net power is:

[0065] definition The permissible three-phase power imbalance deviation threshold. The single-phase energy storage discharge demand caused by three-phase imbalance is:

[0066] The single-phase energy storage charging demand caused by three-phase imbalance is:

[0067] definition Single-phase line voltage, As the lower limit of allowable voltage, The upper limit of the allowable voltage, This represents the sensitivity coefficient of single-phase energy storage discharge to voltage boost. The sensitivity coefficient for single-phase energy storage charging to voltage drop. The low-voltage discharge demand and high-voltage charging demand for a single-phase line are as follows:

[0068]

[0069] Therefore, single-phase energy storage The partial discharge requirement is:

[0070] in, To meet the heavy overload discharge requirements of single-phase lines, This is to address the single-phase energy storage discharge demand caused by the three-phase imbalance in a single-phase circuit. This is to meet the low-voltage discharge requirements of single-phase lines.

[0071] Single-phase energy storage The local charging demand is as follows:

[0072] To meet the reverse overload charging requirements of single-phase lines, To meet the charging needs of new energy consumption on single-phase lines. This addresses the single-phase energy storage charging demand caused by the three-phase imbalance in a single-phase circuit. To meet the high-voltage charging needs of single-phase lines.

[0073] For three-phase load lines, the definition is... This refers to the permissible capacity or equivalent safe capacity of a three-phase load line. The safe load rate threshold for a three-phase load line. This represents the maximum allowable reverse power for a three-phase load line. This refers to the allowable reverse power transmission of three-phase load lines in the calculation of renewable energy consumption. The heavy overload discharge demand of the three-phase load lines, the heavy overload charging demand in the reverse direction, and the charging demand for renewable energy consumption are as follows:

[0074]

[0075]

[0076] definition This refers to the equivalent voltage or three-phase voltage evaluation quantity of a three-phase load line. This represents the sensitivity coefficient of three-phase energy storage discharge to the voltage boost of three-phase lines. The sensitivity coefficient of three-phase energy storage charging to the voltage drop of three-phase lines. The low-voltage discharge demand and high-voltage charging demand of the three-phase lines are as follows:

[0077]

[0078] Three-phase energy storage The partial discharge demand and partial charging demand are as follows:

[0079]

[0080] These are the heavy overload discharge requirements and low voltage discharge requirements for three-phase load lines, respectively. These are respectively the reverse overload charging demand of three-phase load lines, the charging demand for new energy consumption, and the high-voltage charging demand.

[0081] Step 104: Determine the rated power and rated capacity of the single-phase energy storage device and the three-phase energy storage device based on their partial discharge and partial charging requirements.

[0082] This implementation method determines the rated power of energy storage based on the maximum instantaneous demand and the rated capacity of energy storage based on the cumulative energy demand during continuous high-risk periods and continuous periods of renewable energy surplus, thereby improving the targeting and rationality of energy storage configuration. Specifically, for each energy storage device in single-phase and three-phase energy storage devices, the maximum partial discharge demand and maximum partial charging demand of the energy storage device are determined based on its partial discharge demand and partial charging demand; the rated power of the energy storage device is then determined based on the maximum partial discharge demand and maximum partial charging demand. For the rated capacity: the discharge efficiency and charging efficiency of the energy storage device are obtained; based on the discharge efficiency and charging efficiency of the energy storage device and its partial discharge demand and partial charging demand, the partial discharge energy, partial charging absorbed energy, and renewable energy absorbed energy of the energy storage device are determined; the preset upper limit of SOC, lower limit of SOC, discharge SOC ratio, charging SOC ratio, and reserved SOC space ratio of the energy storage device are obtained, and the rated capacity of the energy storage device is determined using the following formula:

[0083] in, For partial discharge energy, Absorb energy for local charging, Energy is absorbed by new energy sources; This refers to the discharge SOC ratio. This refers to the charging SOC ratio. To reserve a certain proportion of SOC space.

[0084] Determining the rated capacity of each energy storage device (including single-phase and three-phase energy storage devices) specifically includes: definition For a continuous set of risk periods, This is a collection of consecutive periods of surplus renewable energy. For energy storage The discharge efficiency, For energy storage Charging efficiency. Energy storage. The energy requirements for partial discharge, partial charging absorption, and renewable energy consumption are as follows:

[0085]

[0086]

[0087] definition For energy storage The lower limit of SOC, For energy storage SOC upper limit, For energy storage The SOC ratio that can be used for discharge support For energy storage The SOC ratio that can be used for charging absorption. For energy storage The proportion of SOC space reserved for the consumption of new energy sources. Definition For energy storage Given the rated capacity, then:

[0088] The rated power and rated capacity of each energy storage device are finally obtained through the above calculations: Phase A line energy storage device B-phase line energy storage device C-phase line energy storage device Three-phase energy storage device .

[0089] Step 105: Collect the operating status data of the low-voltage distribution area, and determine the location of the line with risk and the type of risk based on the operating status data.

[0090] In this implementation, the locations of lines where risks can be identified include both local lines and the entire distribution area. Local lines refer to single-phase lines (A / B / C phases) and three-phase load lines, while the entire distribution area refers to the distribution transformer side or the distribution area outlet. Based on the location of the line with risk, the corresponding energy storage device is activated for charging and discharging.

[0091] The system collects voltage, current, power direction, renewable energy output, and load power data for single-phase lines, three-phase load lines, and transformer outlets in low-voltage distribution areas A, B, and C. It also collects SOC, dischargeable power, rechargeable power, and energy storage access switch status data for single-phase and three-phase energy storage devices to obtain operational status data.

[0092] During the operation of the distribution zone controller Periodically collect voltage, current, power direction, renewable energy output, and load power data from single-phase lines (A / B / C), three-phase load lines, and distribution transformers or transformer substations. Simultaneously, collect data from each energy storage device. Dischargeable power Rechargeable power and energy storage access switch status .in, Indicates energy storage The corresponding line has been connected and control operations are permitted. This indicates that the energy storage system is not connected or has been taken out of service.

[0093] Based on the collected operational status data, the charging and discharging requirements under each risk scenario are calculated to determine whether a risk exists in that scenario. The net power, power in the direction of power purchase, power in the direction of reverse transmission, and surplus renewable energy power of any single-phase line or three-phase load line are calculated based on the operational status data. Risk indicator variables for each risk type of that line are determined based on the net power, power in the direction of power purchase, power in the direction of reverse transmission, and surplus renewable energy power; these risk indicator variables indicate the presence of risk. The overall net power, power in the direction of power purchase, and power in the direction of reverse transmission of the transformer substation are calculated based on the operational status data. The overall risk indicator variables for the transformer substation are determined based on the overall net power, power in the direction of power purchase, and power in the direction of reverse transmission of the transformer substation.

[0094] If the net power, power purchased, power transmitted in the reverse direction, and surplus power of new energy do not meet their respective preset conditions, the risk flag variable for the corresponding risk type will be 1, indicating that there is a risk.

[0095] runtime segment Within the region, the net power of the transmission line, the power in the direction of power purchase, the power in the direction of power transmission back, and the surplus power of renewable energy are as follows:

[0096]

[0097]

[0098]

[0099] For any line ,definition , , , and These are the risk indicator variables for heavy overload, heavy overload in the reverse direction, surplus renewable energy, low voltage, and high voltage:

[0100]

[0101]

[0102]

[0103]

[0104] For single-phase lines A / B / C, further identify the risk of three-phase imbalance. Define the operating segment. The three-phase average net power is:

[0105] Define a single-phase line The net power deviation is:

[0106] The risk indicators for discharge-type three-phase imbalance and charging-type three-phase imbalance are as follows:

[0107]

[0108] For the overall risk at the distribution transformer or transformer substation outlet level, the overall net power of the transformer substation, the overall power in the power purchase direction of the transformer substation, and the power in the power reverse direction of the transformer substation are defined as follows:

[0109]

[0110]

[0111] The overall overload risk indicator variables for the transformer area and the overall reverse direction overload risk indicator variables for the transformer area are as follows:

[0112]

[0113] The overall safe load rate threshold for the transformer area. This refers to the overall allowable capacity or equivalent safe capacity of the transformer substation. This represents the maximum power that the entire distribution area is allowed to transmit back.

[0114] Step 106: Control the operation of the corresponding energy storage device according to the line location and risk type.

[0115] Based on the line with risk and the type of risk, the corresponding energy storage device on that line is invoked to charge or discharge, and the charging or discharging command for that energy storage device is determined.

[0116] The aforementioned risk types can be categorized into two types: discharge support and charge absorption. Discharge support risks are further divided into three-phase imbalances caused by heavy overload, low voltage, or excessive net load. Charge absorption risks are specifically divided into three-phase imbalances caused by reverse heavy overload, high voltage, excess renewable energy, or insufficient net load. If the risk type is heavy overload, low voltage, or excessive net load three-phase imbalance, the corresponding energy storage device enters discharge mode. When there are risks of reverse overload, high voltage, excess renewable energy, or insufficient net load three-phase imbalance, the corresponding energy storage device enters charging mode.

[0117] Specifically, if the line location is any single-phase line (A, B, or C), the operating mode of the single-phase energy storage device corresponding to the single-phase line is determined based on the risk indicator variable indicating the risk, and the single-phase energy storage device is then activated to operate according to the operating mode. If the line location is a three-phase load line, the operating mode of the three-phase energy storage device is determined based on the risk indicator variable, and the three-phase energy storage device is then activated to operate according to the operating mode. If the line location is at the transformer substation outlet, the target energy storage device is selected from the single-phase and three-phase energy storage devices based on the operating mode corresponding to the risk indicator variable, and the target energy storage device is then activated to operate.

[0118] When a risk occurs on a single-phase line (phase A), priority should be given to using... When a risk occurs on a single-phase B line, priority should be given to using [the appropriate circuit]. When a risk occurs on a single-phase C line, priority should be given to using [the appropriate circuit]. When a risk occurs on a three-phase load line, priority should be given to activating [the appropriate circuit]. The correspondence between local risks and priority action energy storage is shown in Table 2. When a risk occurs at the transformer substation outlet or transformer side, the substation controller selects one or more energy storage devices to respond in a coordinated manner based on the energy storage status.

[0119] Table 2. Correspondence between local risks and priority action energy storage

[0120] Define energy storage During the period The operating mode is Its value is:

[0121] When the line When there is a risk of three-phase imbalance due to heavy overload, low voltage, or excessive net load, the corresponding energy storage will enter discharge mode; when the line... When there is a risk of three-phase imbalance due to reverse overload, high voltage, surplus renewable energy, or low net load, the corresponding energy storage will enter charging mode; when the line When no risks requiring energy storage participation in governance are identified and the energy storage status is normal, the corresponding energy storage enters standby mode; when the energy storage SOC exceeds the limit, equipment fails, communication is abnormal, or the energy storage access switch is unavailable, the corresponding energy storage enters exit mode.

[0122] This embodiment also includes: determining a charging / discharging power command for the energy storage device, and controlling the energy storage device to discharge or charge at a specific power using the charging / discharging power command. When the operating mode of the single-phase energy storage device or the three-phase energy storage device is discharging, the energy storage discharge power command is:

[0123] To call up the operating energy storage device Rated power, For routes with risks The partial discharge requirement, For energy storage devices The dischargeable power; when the single-phase energy storage device and the three-phase energy storage device are in charging mode, the energy storage charging power command is:

[0124] The rechargeable power of the energy storage device ES. For routes with risks Localized charging needs.

[0125] If the risk indicator variable for overall overload in the transformer area is 1, then target energy storage devices are selected from the following set in descending order of State of Charge (SOC) and dischargeable power:

[0126] in For the collection of routes, This represents a three-phase load line, where A, B, and C are single-phase lines (phase A, phase B, and phase C), respectively, and i represents any line. Let i be the current SOC of the energy storage device. For the energy storage device corresponding to line i The lower limit of SOC, For energy storage devices Dischargeable power, The energy storage access switch is in the current state. Indicates energy storage device The corresponding line has been connected. This indicates that the energy storage device is not connected.

[0127] The discharge command for the selected target energy storage device satisfies:

[0128] If the risk indicator variable for the overall reverse heavy overload of the transformer area is 1, then target energy storage devices are selected according to the method of SOC from low to high and rechargeable power from high to low:

[0129] For the energy storage device corresponding to line i SOC upper limit; The charging command for the selected target energy storage device satisfies:

[0130] Update the SOC after executing the discharge or charge command.

[0131] For localized risk, the definition is... For the line The partial discharge requirement is defined. For the line The partial charging demand. When the energy storage performs discharge, the energy storage discharge power command is:

[0132] When the energy storage system is charging, the energy storage charging power command is:

[0133] Furthermore, when At that time, the entire distribution area faces a risk of severe overload. The distribution area controller selects one or more energy storage devices from the available energy storage set to participate in the discharge. The available energy storage set is as follows:

[0134] The overall demand reduction for heavy overload in the transformer area is as follows:

[0135] in, Power purchased from the distribution area.

[0136] The distribution area controller prioritizes energy storage devices with higher SOC and larger discharge power for response; if a single energy storage device cannot meet the overall heavy overload reduction requirements, multiple energy storage devices will be selected to discharge together. For the selected energy storage devices, their discharge commands must satisfy:

[0137] Furthermore, when At that time, the entire distribution area faces a risk of heavy overload in the reverse direction. The distribution area controller selects one or more energy storage units from the available energy storage set to participate in charging. The available energy storage set is as follows:

[0138] The overall reverse transmission direction demand in the transformer area is as follows:

[0139] This refers to the overall reverse power of the distribution area.

[0140] The distribution area controller prioritizes energy storage with lower SOC and higher rechargeable power for response; if surplus renewable energy is concentrated on a particular power line, then the energy storage corresponding to that line is prioritized for charging. For the selected energy storage, its charging command satisfies:

[0141] Based on the operating status data of the distribution area at each time t, the corresponding charging and discharging power command for the energy storage device is determined, thereby issuing the energy storage charging and discharging power command, executing energy storage access or exit control, and feeding back the execution results to the distribution area controller to form a closed-loop control. At the same time, the charging, discharging, standby, or exit mode of the energy storage device is determined based on the location of the risk line, risk type, SOC, available power, and energy storage access switch status, and is updated over time t.

[0142] In this implementation, an operation control mechanism of "local risk response on-site and overall risk coordinated scheduling" is established. When the risk occurs on a single-phase line (A / B / C) or a three-phase load line, the energy storage at the head end of the corresponding line is prioritized for charging or discharging. When the risk occurs at the overall transformer area level, the available energy storage set is selected based on the SOC, available power and access switch status of each energy storage unit, and one or more energy storage units are selected for coordinated response, thereby taking into account both local governance and overall regulation.

[0143] Furthermore, after executing charge / discharge commands, the SOC of the energy storage system should be updated to meet the upper and lower limit constraints. The energy storage SOC update equation is as follows:

[0144] And satisfy:

[0145] To avoid the same energy storage device being charged and discharged simultaneously during the same period, a definition is provided. and These are the charging state variables and the discharging state variables, respectively, and they satisfy the following:

[0146] Through tiered configuration and switching control of energy storage, energy storage can simultaneously participate in heavy overload reduction, reverse power flow suppression, absorption of surplus renewable energy, voltage support, and improvement of three-phase imbalance. Furthermore, by employing SOC constraints, charge / discharge mutual exclusion constraints, and multi-risk priority rules, the safety, feasibility, and engineering applicability of the control process are enhanced, thereby improving the comprehensive capabilities of renewable energy consumption and safety management in low-voltage distribution areas.

[0147] Furthermore, when multiple risks occur simultaneously within the same time period, i.e., the risk indicator variables for multiple risk types are all 1, the corresponding energy storage device is identified, and charging / discharging commands (charging or discharging commands) are executed on each energy storage device according to a preset priority. The energy storage area controller determines the control action according to the safety priority principle, with the priority being: heavy overload. Reverse overload Voltage over-limit Three-phase imbalance Surplus New Energy Consumption Economic operation.

[0148] The system architecture diagram of the method described in this embodiment is as follows: Figure 3 As shown. Reference Figure 3 The distribution area controller periodically collects operational status data, including electrical parameters of each line, such as voltage, current, and power direction; energy storage status parameters, such as SOC, rechargeable power, and dischargeable power; and switch status, specifically switch connection or disconnection. Based on the collected operational status data, the location of any existing risk is determined. In this embodiment, risk locations are categorized into two types: local line risks and overall distribution area risks. Local line risks include single-phase lines (A / B / C phases) and three-phase load lines. Overall distribution area risks refer to risks present at the distribution transformer or distribution area outlet. The risk type is further determined based on the specific risk location. If the risk is a local line risk and the risk type is discharge support type (i.e., heavy overload, low voltage, high net load type three-phase imbalance), the corresponding line's energy storage is invoked to execute energy storage charging / discharging commands. If the risk is an overall distribution area risk and the risk type is discharge support type (overall distribution area heavy overload), an available energy storage set is selected, and multiple energy storage units are chosen for coordinated response based on priority. Then, the energy storage device is updated with its charging, discharging, standby, and exit states, and the SOC and switching states are updated before entering the next control cycle.

[0149] By employing the above method, a correspondence is established between energy storage configuration location, line risk requirements, real-time risk identification, and energy storage control actions. This ensures that risks associated with single-phase lines (A / B / C) are prioritized for management by the corresponding single-phase energy storage, risks associated with three-phase load lines are prioritized for management by three-phase energy storage, and overall risks in the distribution area are managed collaboratively by multiple energy storage units. Compared to traditional centralized energy storage solutions for low-voltage distribution areas, this solution can more accurately target the location of risks within the low-voltage distribution area, improving the local absorption capacity of distributed renewable energy and the safe operation level of the low-voltage distribution area.

[0150] Furthermore, this embodiment also provides a low-voltage tiered energy storage control device for new energy consumption, which can be used to execute the above-mentioned low-voltage tiered energy storage control method for new energy consumption. The system includes the following modules: a tiered energy storage configuration module for configuring single-phase energy storage devices in single-phase lines A, B, and C of the low-voltage distribution area, and three-phase energy storage devices in three-phase load lines; a charging and discharging demand calculation module for collecting load power and renewable energy output from each single-phase and three-phase load line, and calculating the discharge and charging demands of each single-phase and three-phase load line under various risk scenarios; a risk demand calculation module for calculating the partial discharge and partial charging demands of single-phase and three-phase energy storage devices based on the discharge and charging demands under various risk scenarios; an energy storage power and capacity determination module for determining the rated power and rated capacity of single-phase and three-phase energy storage devices based on their partial discharge and partial charging demands; a risk identification module for collecting operating status data of the low-voltage distribution area, and determining the location and type of risky lines based on this data; and a switching control decision module for controlling the operation of the corresponding energy storage devices based on the line location and risk type.

[0151] The specific details of each module or unit in the aforementioned low-voltage tiered energy storage control device for new energy consumption have been described in detail in the corresponding low-voltage tiered energy storage control method for new energy consumption, so they will not be repeated here.

[0152] This application also provides an electronic device, including a processor and a memory, wherein the memory stores one or more computer programs, and the one or more computer programs include instructions that, when executed by the electronic device, implement the above-described method. Specifically, according to embodiments of this application, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of this disclosure include a computer program product comprising a computer program carried on a computer-readable storage medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via the communication portion of a network interface card such as a LAN card or modem, and / or installed from a removable medium such as a disk, optical disk, magneto-optical disk, or semiconductor memory. When the computer program is executed by a processor (CPU), it performs the functions defined in the embodiments of this application.

[0153] It should be noted that the computer-readable medium shown in this application can be a computer-readable signal medium or a computer-readable storage medium, or any combination thereof. A computer-readable storage medium can be, for example,—but not limited to—an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this disclosure, a computer-readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. In this disclosure, a computer-readable signal medium can include a data signal propagated in baseband or as part of a carrier wave, carrying computer-readable program code. Such propagated data signals can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. Computer-readable signal media can also be any computer-readable medium other than computer-readable storage media, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to: wireless, wire, optical fiber, RF, etc., or any suitable combination thereof.

[0154] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this disclosure. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram or flowchart, and combinations of blocks in a block diagram or flowchart, may be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0155] The units described in the embodiments of this disclosure can be implemented in software or hardware, and the described units can also be located in a processor. The names of these units do not necessarily limit the unit itself.

[0156] In another aspect, this application also provides a computer-readable medium, which may be included in the electronic device described in the above embodiments; or it may exist independently and not assembled into the electronic device. The computer-readable medium carries one or more programs, which include instructions that, when executed by the electronic device, cause the electronic device to perform the methods described in the above embodiments.

[0157] It should be noted that although several modules or units for the device used to perform actions have been mentioned in the detailed description above, this division is not mandatory. In fact, according to the embodiments of this application, the features and functions of two or more modules or units described above can be embodied in one module or unit. Conversely, the features and functions of one module or unit described above can be further divided and embodied by multiple modules or units.

[0158] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A low-voltage, tiered energy storage control method for renewable energy consumption, characterized in that, include: Single-phase energy storage devices are installed in the single-phase lines A, B, and C of the low-voltage distribution area, and three-phase energy storage devices are installed in the three-phase load lines. Collect the load power and renewable energy output of each single-phase line and three-phase load line, and calculate the discharge and charging requirements of each single-phase line and three-phase load line under various risk scenarios based on the load power and renewable energy output. Calculate the partial discharge and partial charging requirements of single-phase and three-phase energy storage devices based on the discharge and charging requirements under various risk scenarios. The rated power and rated capacity of single-phase and three-phase energy storage devices are determined based on their partial discharge and partial charging requirements. Collect operational status data of low-voltage distribution areas, and determine the location of lines with risks and the type of risks based on the operational status data; The operation of the corresponding energy storage device is controlled according to the location of the line and the type of risk.

2. The method according to claim 1, characterized in that, The calculation of discharge and charging demands for each single-phase and three-phase load line under various risk scenarios based on load power and renewable energy output includes: The net power, power in the direction of power purchase, power in the direction of power transmission, and surplus power of new energy are calculated by using the load power of a single-phase line and the output of new energy sources. Based on net power, power in the direction of power purchase, power in the direction of reverse power transmission, and surplus power of renewable energy, determine the heavy overload discharge demand, reverse heavy overload charging demand, renewable energy consumption charging demand, low voltage discharge demand, and high voltage charging demand of each single-phase line under risk scenarios of heavy overload, reverse heavy overload, renewable energy surplus, high and low voltage, and three-phase imbalance, as well as the single-phase energy storage discharge demand and single-phase energy storage charging demand caused by three-phase imbalance, and the heavy overload discharge demand, reverse heavy overload charging demand, renewable energy consumption charging demand, low voltage discharge demand, and high voltage charging demand of three-phase load lines.

3. The method according to claim 1, characterized in that, The calculation of partial discharge and partial charging requirements for single-phase and three-phase energy storage devices based on discharge and charging requirements under various risk scenarios includes: The partial discharge requirement for a single-phase energy storage device is: in, To meet the heavy overload discharge requirements of single-phase lines, This is to address the single-phase energy storage discharge demand caused by the three-phase imbalance in a single-phase circuit. To meet the low-voltage discharge requirements of single-phase lines; The partial discharge requirement for a single-phase energy storage device is: To meet the reverse overload charging requirements of single-phase lines, To meet the charging needs of new energy consumption on single-phase lines. This addresses the single-phase energy storage charging demand caused by the three-phase imbalance in a single-phase circuit. To meet the high-voltage charging needs of single-phase lines; The partial discharge requirement for three-phase energy storage devices is: These are the heavy overload discharge requirements and low voltage discharge requirements for three-phase load lines, respectively. The partial charging demand of three-phase energy storage devices is as follows: These are respectively the reverse overload charging demand of three-phase load lines, the charging demand for new energy consumption, and the high-voltage charging demand.

4. The method according to claim 1, characterized in that, The determination of the rated power and rated capacity of single-phase and three-phase energy storage devices based on their partial discharge and partial charging requirements includes: For each energy storage device in a single-phase energy storage device and a three-phase energy storage device, the maximum partial discharge demand and the maximum partial charge demand of the energy storage device are determined based on the partial discharge demand and the partial charge demand of the energy storage device. The rated power of the energy storage device is determined by the maximum partial discharge demand and the maximum partial charge demand. Obtain the discharge efficiency and charging efficiency of the energy storage device; Based on the discharge efficiency and charging efficiency of the energy storage device, as well as the partial discharge demand and partial charging demand of the energy storage device, determine the partial discharge energy, partial charging absorption energy, and new energy consumption energy of the energy storage device. Obtain the preset upper limit of SOC, lower limit of SOC, discharge SOC ratio, charging SOC ratio, and reserved SOC space ratio of the energy storage device, and determine the rated capacity of the energy storage device using the following formula: in, For partial discharge energy, Absorb energy for local charging, Energy is absorbed by new energy sources; This refers to the discharge SOC ratio. This refers to the charging SOC ratio. To reserve a certain proportion of SOC space.

5. The method according to claim 1, characterized in that, The collected low-voltage distribution area's operational status data includes: The system collects voltage, current, power direction, renewable energy output, and load power data for single-phase lines, three-phase load lines, and transformer outlets in low-voltage distribution areas A, B, and C. It also collects SOC, dischargeable power, rechargeable power, and energy storage access switch status data for single-phase and three-phase energy storage devices to obtain operational status data.

6. The method according to claim 5, characterized in that, The process of determining the location and type of risk on lines based on operational status data includes: Calculate the net power, power in the direction of power purchase, power in the direction of reverse power transmission, and surplus power of new energy for any single-phase line or three-phase load line based on the operating status data. The risk indicator variables for each risk type of the line are determined based on net power, power purchased in the direction of power, power transmitted in the direction of power, and surplus power of new energy sources. These risk indicator variables are used to indicate whether there is a risk. Calculate the overall net power of the transformer area, the overall power in the direction of power purchase of the transformer area, and the overall power in the direction of power transmission of the transformer area based on the operating status data. The risk indicator variables for the entire transformer substation are determined based on the overall net power of the substation, the overall power purchased by the substation, and the overall power transmitted back to the substation.

7. The method according to claim 1, characterized in that, The method of controlling the operation of corresponding energy storage devices based on line location and risk type includes: If the line location is any single-phase line A, B, or C, the operating mode of the single-phase energy storage device corresponding to the single-phase line is determined based on the risk indicator variable indicating the risk, and the single-phase energy storage device is called to operate according to the operating mode. If the line location is a three-phase load line, the operating mode of the three-phase energy storage device is determined according to the risk indicator variables, and the three-phase energy storage device is called to operate according to the operating mode. If the line location is at the transformer substation exit, the target energy storage device is selected from single-phase and three-phase energy storage devices according to the operating mode corresponding to the risk indicator variable, and the target energy storage device is called to operate.

8. The method according to claim 7, characterized in that, Also includes: When the operating mode of a single-phase energy storage device or a three-phase energy storage device is discharge, the energy storage discharge power command is: To call up the operating energy storage device Rated power, For routes with risks The partial discharge requirement, For energy storage devices The dischargeable power; When the operating mode of a single-phase energy storage device or a three-phase energy storage device is charging, the energy storage charging power command is: The rechargeable power of the energy storage device ES. For routes with risks Localized charging needs.

9. The method according to claim 8, characterized in that, The step of selecting target energy storage devices from single-phase and three-phase energy storage devices based on the operating mode corresponding to the risk indicator variables includes: If the risk indicator variable for overall overload in the transformer area is 1, then target energy storage devices are selected from the following set in descending order of State of Charge (SOC) and dischargeable power: in For the collection of routes, This represents a three-phase load line, where A, B, and C are single-phase lines (phase A, phase B, and phase C), respectively, and i represents any line. Let i be the current SOC of the energy storage device. For the energy storage device corresponding to line i The lower limit of SOC, For energy storage devices Dischargeable power, The energy storage access switch is in the current state. Indicates energy storage device The corresponding line has been connected. This indicates that the energy storage device is not connected. The discharge command for the selected target energy storage device satisfies: If the risk indicator variable for the overall reverse heavy overload of the transformer area is 1, then target energy storage devices are selected according to the method of SOC from low to high and rechargeable power from high to low: For the energy storage device corresponding to line i SOC upper limit; The charging command for the selected target energy storage device satisfies: Update the SOC after executing the discharge or charge command.

10. A low-voltage, tiered energy storage control device for renewable energy consumption, characterized in that, include: The energy storage tiered configuration module is used to configure single-phase energy storage devices in the A, B, and C single-phase lines of the low-voltage distribution area, and to configure three-phase energy storage devices in the three-phase load lines. The charging and discharging demand calculation module is used to collect the load power and renewable energy output of each single-phase line and three-phase load line, and calculate the discharge and charging demands of each single-phase line and three-phase load line under various risk scenarios based on the load power and renewable energy output. The risk demand calculation module is used to calculate the partial discharge and partial charging demands of single-phase and three-phase energy storage devices based on the discharge and charging demands under various risk scenarios. The energy storage power capacity determination module is used to determine the rated power and rated capacity of single-phase energy storage devices and three-phase energy storage devices based on their partial discharge and partial charging requirements. The risk identification module is used to collect the operating status data of low-voltage distribution areas and determine the location of lines with risks and the type of risks based on the operating status data; The switching control decision module is used to control the operation of the corresponding energy storage device based on the line location and risk type.

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