Energy storage system frequency modulation and UPS dual-function cooperative control system and method based on SOC partition

Abstract

The system comprises an energy storage auxiliary thermal power generating unit frequency modulation system, the energy storage auxiliary thermal power generating unit system is connected with a high-voltage plant bus, and the energy storage auxiliary thermal power generating unit system internally comprises an EMS system and one or more energy storage power supply systems; the station service power detection module obtains station service power state information including station service power voltage and frequency from the EMS system, and when it is detected that station service power is abnormal, the voltage drop is smaller than or equal to 20%, and the frequency deviation is smaller than or equal to + / -0.5 Hz, an NDC fast direct current circuit breaker in the energy storage system is switched off, an EMS side NDC fast direct current circuit breaker is switched on, and a bypass switch is switched off; the SOC state information of the energy storage system is collected in real time, and the instantaneous power demand is calculated and issued to the energy storage unit; meanwhile, the service power detection module monitors whether the service power state is restored in real time; and after the station service power state is restored, the NDC fast direct current circuit breaker in the energy storage system is switched on, the NDC fast direct current circuit breaker on the EMS side is switched off, and the bypass switch is switched on.

Description

Technical Field

[0001] The present invention belongs to the technical field of energy storage power stations, and specifically relates to a dual-function coordinated control system and method for frequency regulation of an energy storage system and UPS based on SOC partitioning. Background Art

[0002] With the rapid increase in the capacity of independent and auxiliary energy storage power stations, the system architecture of energy storage systems is being continuously optimized based on site conditions. To ensure the lifespan and safety of lithium batteries, traditional energy storage power stations set upper and lower SOC limits to prevent overcharging and over-discharging. This also results in some of the energy storage system's available capacity being left idle for long periods of time, making it difficult to realize economic benefits. By dedicating part of the energy storage system's capacity to UPS functions, the system can be efficiently utilized, eliminating the investment in independent UPS equipment and reducing operating and maintenance costs.

[0003] UPS systems are typically not frequently charged and discharged during daily use. They are designed to be in a floating charge state when plant power is normal, switching to battery power only in the event of a power outage or an anomaly, ensuring uninterrupted operation of critical equipment. However, to ensure battery performance and lifespan, regular charging and discharging maintenance is necessary. The power and capacity of energy storage power stations far exceed the power capacity of UPSs, and the available capacity of energy storage systems is compatible with UPS functions. Energy storage also requires regular maintenance and inspections for safety reasons. Energy storage systems overlap with UPSs in functionality and safety. A dual-function coordinated control method for energy storage system frequency regulation and UPS based on SOC zoning is adopted. While ensuring safety, this method deeply integrates frequency regulation response and UPS power supply functions to maximize the value of energy storage capacity. Summary of the Invention

[0004] The purpose of the present invention is to provide a dual-function coordinated control system and method for frequency regulation and UPS of an energy storage system based on SOC zoning. Through the control strategy and system structure, the SOC is divided into dedicated intervals for frequency regulation (20%-80%) and UPS (10%-80%), and the charging and discharging priority and power limiting strategy are dynamically managed to achieve lossless switching between frequency regulation response and uninterruptible power supply, reduce equipment redundancy costs, and improve the overall economy of the system.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A dual-function coordinated control system for energy storage system frequency regulation and UPS based on SOC partitioning, including an energy storage-assisted thermal power unit frequency regulation system, the energy storage-assisted thermal power unit system being connected to the high-voltage plant bus, and the energy storage-assisted thermal power unit system internally including an EMS system and one or more energy storage power supply systems;

[0007] The energy storage power supply system includes a high-voltage side grid-connected switch, an energy storage transformer, an energy storage converter device PCS, an energy storage unit, an NDC fast DC circuit breaker inside the energy storage system, a UPS output isolation transformer, and an NDC fast DC circuit breaker on the EMS side; the flywheel energy storage high-voltage side grid-connected switch is connected to the high-voltage plant bus; the energy storage converter device PCS is connected to the high-voltage side grid-connected switch via an energy storage transformer; the energy storage unit is connected to the energy storage converter device PCS via an NDC fast DC circuit breaker inside the energy storage system;

[0008] The EMS system includes an EMS controller body, a plant power detection module, a 220V plant power bus, a secondary equipment cabinet, a bypass switch and a station DC bus; the EMS system exchanges communication information with the plant power detection module; the EMS system is connected to the energy storage converter through the EMS side NDC fast DC circuit breaker and the UPS output isolation transformer; the EMS system exchanges communication information with the energy storage converter PCS; the EMS system is connected to the 220V plant power bus; the 220V plant power bus is connected to the station DC bus through the bypass switch; the secondary equipment cabinet is connected to the EMS controller body through the station DC bus.

[0009] A further improvement of the present invention is that the SOC interval in the energy storage power supply system is divided into four sections: 0%-10% is a discharge-prohibited area, 10%-20% is a UPS dedicated capacity area, 20%-80% is a frequency-modulated UPS dynamic sharing area, and 80%-100% is a charging-prohibited area.

[0010] A method for collaboratively controlling frequency regulation and UPS dual functions of an energy storage system based on SOC partitioning is provided. The method is based on the aforementioned collaborative control system for frequency regulation and UPS dual functions of an energy storage system based on SOC partitioning, and includes:

[0011] The auxiliary power detection module obtains auxiliary power status information, including auxiliary power voltage and frequency, from the EMS system. When an auxiliary power abnormality is detected (voltage drop ≤ 20% and frequency deviation ≤ ±0.5Hz), the NDC fast DC circuit breaker inside the energy storage system is disconnected, the NDC fast DC circuit breaker on the EMS side is closed, and the bypass switch is disconnected. The instantaneous power demand is calculated by real-time acquisition of the SOC status information of the energy storage system and transmitted to the energy storage unit. Simultaneously, the auxiliary power detection module monitors in real time whether the auxiliary power status has been restored. When the auxiliary power status has been restored, the NDC fast DC circuit breaker inside the energy storage system is closed, the NDC fast DC circuit breaker on the EMS side is disconnected, and the bypass switch is closed. The energy storage-assisted thermal power unit system is normally put into frequency regulation, and the DC bus in the station is powered by 220V auxiliary power.

[0012]

[0013] ABN(t) is the abnormal sign of factory power consumption; V grid is the factory power voltage; V rated is the rated voltage of the factory power supply; f grid The factory power frequency.

[0014] A further improvement of the present invention is that when ABN(t)=1, the auxiliary power system is in an abnormal state, the NDC fast DC circuit breaker inside the energy storage system is disconnected, the NDC fast DC circuit breaker on the EMS side is closed, and the bypass switch is disconnected.

[0015] A further improvement of the present invention is that when ABN(t)=0, the auxiliary power system is in normal state, the NDC fast DC circuit breaker inside the energy storage system is closed, the NDC fast DC circuit breaker on the EMS side is opened, and the bypass switch is closed.

[0016] A further improvement of the present invention is that when ABN(t)=1, the output power of the energy storage system changes according to the change of SOC, and the output power of the energy storage system is more stable;

[0017]

[0018] Among them, P ups P is the output power of the energy storage system when the plant power supply is abnormal, and P is the rated power of the UPS.

[0019] A further improvement of the present invention is that when ABN(t)=0, the EMS system determines the differential power of the thermal power unit by taking the difference between the AGC target power value of the unit issued by the dispatcher and the real-time active power of the corresponding thermal power unit, and determines the adjusted target power of each energy storage unit corresponding to the thermal power unit according to the differential power of the thermal power unit, the maximum adjustable power of the energy storage corresponding to the thermal power unit participating in frequency regulation, and the active power adjustment dead zone parameter.

[0020] A further improvement of the present invention is that when the difference power is within the dead zone of energy storage active power adjustment, the energy storage system does not output power;

[0021] When the difference power exceeds the positive deviation dead zone and is less than the maximum dischargeable power of the energy storage, the energy storage output power is equal to the difference power; the internal unit power of the energy storage is distributed to the corresponding PCS in proportion to the dischargeable energy storage unit;

[0022] When the difference power exceeds the positive deviation dead zone and is greater than the maximum dischargeable power of the energy storage, the energy storage outputs the maximum dischargeable power; the internal unit power of the energy storage is distributed to the corresponding PCS in proportion to the dischargeable energy storage unit;

[0023] When the difference power exceeds the negative deviation dead zone and is greater than the maximum rechargeable power of the energy storage, the energy storage output power is equal to the difference power; the power of the internal unit of the energy storage is distributed to the corresponding PCS in proportion to the rechargeable energy storage unit;

[0024] When the difference power exceeds the negative deviation dead zone range and is less than the maximum rechargeable power of the energy storage, the energy storage outputs the maximum rechargeable power; the power of the internal unit of the energy storage is distributed to the corresponding PCS in proportion to the rechargeable energy storage unit;

[0025] When the maximum chargeable power of the energy storage is 0, the energy storage system will refuse to execute the charge instruction; when the maximum dischargeable power of the energy storage is 0, the energy storage system will refuse to execute the discharge instruction;

[0026]

[0027] in, is the target power adjustment of energy storage, σ n Adjust the dead zone parameter for the active power of energy storage, ΔP n is the difference power between the thermal power unit and the AGC instruction, is the maximum dischargeable power of energy storage; The maximum chargeable power of the energy storage.

[0028] A further improvement of the present invention is that the maximum discharge power of the energy storage Is a positive value.

[0029] A further improvement of the present invention is that the maximum chargeable power of the energy storage is a negative value.

[0030] Compared with the prior art, the present invention has at least the following beneficial technical effects:

[0031] The present invention provides a dual-function coordinated control system and method for frequency modulation and UPS based on SOC zoning for energy storage systems. By dividing SOC intervals (20%-80% for frequency modulation and 10%-80% for UPS), available capacity is converted into UPS resources, eliminating the need for traditional UPS systems, reducing investment costs, and improving capacity utilization. This control algorithm implements a UPS top-priority control strategy. In the event of a plant power outage or an anomaly, the system shuts off the frequency modulation function within 5ms and dedicates dedicated capacity (10%-20% SOC), ensuring 100% backup power availability, prioritizing frequency modulation requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0033] Figure 1 Schematic diagram of the overall architecture of the energy storage system;

[0034] Figure 2 This is a schematic diagram of lithium battery SOC interval division and management;

[0035] Figure 3 This is the frequency modulation coordinated UPS switching control logic flow chart;

[0036] Figure 4 This is the frequency modulation control block diagram;

[0037] Figure 5 Tracking AGC curve for thermal power units. DETAILED DESCRIPTION

[0038] Hereinafter, only certain exemplary embodiments are briefly described. As will be appreciated by those skilled in the art, the described embodiments may be modified in various ways without departing from the spirit or scope of the present invention. Therefore, the drawings and description are to be considered as illustrative in nature and not restrictive.

[0039] It will be understood that when used in this specification and the appended claims, the terms “comprises” and “comprising” indicate the presence of described features, integers, steps, operations, elements and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof.

[0040] It should also be understood that the terms used in the present specification are only for the purpose of describing particular embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms unless the context clearly indicates otherwise.

[0041] It should be further understood that the term "and / or" used in the present description and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

[0042] The accompanying drawings illustrate various schematic diagrams of structures according to embodiments disclosed herein. These figures are not drawn to scale; for clarity, some details are exaggerated and some details may be omitted. The shapes of the various regions and layers shown in the figures, as well as their relative sizes and positional relationships, are merely exemplary and may deviate in practice due to manufacturing tolerances or technical limitations. Those skilled in the art may design regions / layers with different shapes, sizes, and relative positions as needed.

[0043] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0044] Example 1

[0045] like Figure 1 As shown, the energy storage system frequency regulation and UPS dual-function collaborative control system based on SOC zoning provided by the present invention includes an energy storage-assisted thermal power unit frequency regulation system, the energy storage-assisted thermal power unit system is connected to the high-voltage plant bus 1-1, and the energy storage-assisted thermal power unit system internally includes one or more energy storage power supply systems and EMS systems.

[0046] The energy storage power supply system includes a high-voltage plant bus 1-1, a high-voltage side grid-connected switch 1-2, an energy storage transformer 1-3, an energy storage converter PCS 1-4, an energy storage unit 1-5, an NDC fast DC circuit breaker 1-6 inside the energy storage system, an NDC fast DC circuit breaker 1-7 on the EMS side, and a UPS output isolation transformer 1-8. The flywheel energy storage high-voltage side grid-connected switch 1-2 is connected to the high-voltage plant bus 1-1; the energy storage converter PCS 1-4 is connected to the high-voltage side grid-connected switch 1-2 via the energy storage transformer 1-3; and the energy storage unit 1-5 is connected to the energy storage converter PCS 1-4 via the NDC fast DC circuit breaker 1-6 inside the energy storage system.

[0047] The EMS system includes an EMS system 2-1, a utility power detection module 2-2, a 220V utility power bus 2-3, a secondary equipment cabinet 2-4, a bypass switch 2-5, and an in-station DC bus 2-6. The EMS system 2-1 communicates and exchanges information with the utility power detection module 2-2. The EMS system is connected to the energy storage converter PCS 1-4 via an EMS-side NDC fast DC circuit breaker 1-7 and a UPS output isolation transformer 1-8. The EMS system 2-1 communicates and exchanges information with the energy storage converter PCS 1-4. The EMS controller body 2-1 is connected to the 220V utility power bus 2-3. The 220V utility power bus 2-3 is connected to the in-station DC bus 2-6 via a bypass switch 2-5. The secondary equipment cabinet 2-4 is connected to the EMS controller body 2-1 via the in-station DC bus 2-6.

[0048] like Figure 2 As shown in the figure, the SOC range of the lithium battery energy storage system is divided into four sections: 0%-10% is the prohibited discharge area (marked in red), 10%-20% is the UPS dedicated capacity area (marked in blue), 20%-80% is the frequency modulation UOS dynamic sharing area (marked in green), and 80%-100% is the prohibited charging area (marked in yellow).

[0049] The present invention achieves functional integration by using the energy storage system for both frequency regulation of thermal power units and UPS (uninterruptible power supply) functions. This integrated design eliminates the need for a traditional standalone UPS system, significantly reducing investment costs.

[0050] This invention uses SOC (State of Charge) intervals (20%-80% for frequency modulation, 10%-80% for UPS) to more efficiently convert the energy storage system's available capacity into UPS resources. This division allows the energy storage system to meet frequency modulation requirements while also providing sufficient capacity support for UPS functions, thereby improving overall capacity utilization.

[0051] The control algorithm employed in this invention implements a top-priority UPS control strategy. In the event of a plant power outage or anomaly, the system rapidly shuts down the frequency modulation function within 5ms and dedicates capacity (10%-20% SOC) to ensure 100% backup power availability. This rapid response mechanism ensures that critical loads receive continuous power during power outages, improving system reliability.

[0052] Since the energy storage system supports both frequency modulation and UPS functions, the present invention has high flexibility and scalability. According to actual needs, the SOC interval division or control strategy can be adjusted to adapt to different application scenarios and load requirements.

[0053] The energy storage system of the present invention can absorb and release energy during frequency modulation to balance the supply and demand of the power grid. Simultaneously, in UPS mode, the energy storage system can provide stable power output to ensure the normal operation of critical loads. This dual function enables the energy storage system to utilize energy more efficiently and reduce energy waste.

[0054] Example 2

[0055] like Figure 3 As shown, the present invention provides a method for coordinated control of energy storage system frequency regulation and UPS dual functions based on SOC partitioning, including:

[0056] The auxiliary power detection module obtains auxiliary power status information, including auxiliary power voltage and frequency, from the EMS. If an auxiliary power anomaly is detected (voltage drop ≤ 20% and frequency deviation ≤ ±0.5Hz), it disconnects the NDC fast DC circuit breaker 1-6 within the energy storage system, closes the NDC fast DC circuit breaker 1-7 on the EMS side, and opens the bypass switch 2-5. High-precision sensors collect the energy storage system's SOC status information in real time, calculate the instantaneous power demand, and transmit it to the energy storage unit. Simultaneously, the auxiliary power detection module monitors whether the auxiliary power status has been restored. If the auxiliary power status has been restored, it closes the NDC fast DC circuit breaker 1-6 within the energy storage system, opens the NDC fast DC circuit breaker 1-7 on the EMS side, and closes the bypass switch 2-5. The energy storage power station then operates normally in frequency regulation mode, with the station's DC bus powered by 220V auxiliary power.

[0057]

[0058] ABN(t) is the abnormal sign of factory power consumption; V grid is the factory power voltage; V rated is the rated voltage of the factory power supply; f grid is the auxiliary power frequency. When ABN(t) = 1, the auxiliary power system is abnormal. The NDC fast DC circuit breaker inside the energy storage system is disconnected, and the NDC fast DC circuit breaker on the EMS side is closed. When ABN(t) = 0, the auxiliary power system is normal. The NDC fast DC circuit breaker inside the energy storage system is closed, and the NDC fast DC circuit breaker on the EMS side is disconnected.

[0059] When ABN(t)=1, the output power of the energy storage system changes according to the change of SOC, and the output power of the energy storage system is more stable.

[0060]

[0061] Where Pups is the output power of the energy storage system when the plant power supply is abnormal, and Prated is the rated power of the UPS.

[0062] like Figure 4 As shown, when ABN(t)=0, the EMS system determines the differential power of the thermal power unit based on the difference between the unit AGC target power value issued by the dispatcher and the real-time active power of the corresponding thermal power unit, and determines the adjusted target power of each energy storage unit corresponding to the thermal power unit based on the differential power of the thermal power unit, the maximum adjustable power of the energy storage corresponding to the thermal power unit participating in frequency regulation, and the active power adjustment dead zone parameter.

[0063] (1) When the difference power is within the dead zone of the energy storage active power adjustment, the energy storage system does not output power.

[0064] (2) When the difference power exceeds the positive deviation dead zone and is less than the maximum dischargeable power of the energy storage, the energy storage output power is equal to the difference power. The internal unit power of the energy storage is distributed to the corresponding PCS in proportion to the dischargeable energy storage unit.

[0065] (3) When the power difference exceeds the positive deviation dead zone and is greater than the maximum dischargeable power of the energy storage, the energy storage outputs the maximum dischargeable power. The internal unit power of the energy storage is distributed to the corresponding PCS in proportion to the dischargeable energy storage unit.

[0066] (4) When the difference power exceeds the negative deviation dead zone and is greater than the maximum rechargeable power of the energy storage, the energy storage output power is equal to the difference power. The internal unit power of the energy storage is distributed to the corresponding PCS in proportion to the rechargeable energy storage unit.

[0067] (5) When the difference power exceeds the negative deviation dead zone and is less than the maximum rechargeable power of the energy storage, the energy storage outputs the maximum rechargeable power. The internal unit power of the energy storage is distributed to the corresponding PCS in proportion to the rechargeable energy storage unit.

[0068] (6) When the maximum chargeable power of the energy storage is 0, the energy storage system will refuse to execute the charge instruction. When the maximum dischargeable power of the energy storage is 0, the energy storage system will refuse to execute the discharge instruction.

[0069]

[0070] in, is the target power adjustment of energy storage, σ n Adjust the dead zone parameter for the active power of energy storage, ΔP n is the difference power between the thermal power unit and the AGC instruction, is the maximum dischargeable power of energy storage (positive value); It is the maximum chargeable power of energy storage (negative value).

[0071] Figure 4 In, P Sn is the AGC command of the unit, P Gn It is the real-time active power of the unit.

[0072] Example 3

[0073] This example verifies the effectiveness of the energy storage system frequency regulation and UPS dual-function collaborative control system based on SOC partitioning. Figure 1 The thermal power unit in the system has an output of 600MW, and is equipped with a 20MW / 20MWh energy storage device for auxiliary frequency regulation to form a combined thermal and energy storage system. The rated power of the traditional UPS is 500KW.

[0074] by Figure 5For example, when a thermal power unit suddenly experiences abnormal power consumption during its tracking of the AGC curve, the initial SOC value of the energy storage is set to 50% to simplify the analysis. During the frequency regulation process, the combined thermal and energy storage system changes the circuit breaker state according to the ABN(t) state, thereby achieving mode switching. The frequency regulation power of the thermal and energy storage system and the charge and discharge power of the energy storage system are shown in Figure 2. Figure 5 The simulation results show the power output of the energy storage system in different modes. When the plant power supply is normal, the energy storage system adjusts the power output according to the power difference of the thermal power units. When the plant power supply is abnormal, the energy storage system quickly switches to UPS mode, outputting at rated power to ensure the power supply needs of critical equipment. A comparison of the AGC target power of the thermal power units and the combined power (real-time power of the thermal power units + energy storage power) is also shown. It can be seen that through the auxiliary frequency regulation of the energy storage system, the combined power can better track the AGC target power, improving the frequency regulation performance of the thermal power units.

[0075] In summary, the present invention divides the SOC into dedicated intervals for frequency modulation (20%-80%) and UPS (10%-80%) through control strategy and system structure, dynamically manages charging and discharging priorities and power limiting strategies, realizes lossless switching between frequency modulation response and uninterruptible power supply, reduces equipment redundancy costs and improves the overall economy of the system.

[0076] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, from all points of view, the embodiments should be regarded as illustrative and non-restrictive. The scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes that fall within the meaning and range of equivalents of the claims are included in the present invention. Any reference signs in the claims should not be construed as limiting the claim to which they relate.

[0077] In addition, it should be understood that although this specification describes the embodiments, not every embodiment contains only one independent technical solution. This description is for clarity only. Those skilled in the art should consider the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art. The above content is only for the purpose of illustrating the technical concept of the present invention and cannot be used to limit the scope of protection of the present invention. Any changes made based on the technical solution in accordance with the technical concept proposed by the present invention fall within the scope of protection of the claims of the present invention.

Claims

1. The energy storage system frequency regulation and UPS dual-function coordinated control system based on SOC partitioning is characterized by: It includes an energy storage-assisted thermal power unit frequency regulation system, the energy storage-assisted thermal power unit system is connected to the high-voltage plant bus, and the energy storage-assisted thermal power unit system includes an EMS system and one or more energy storage power supply systems; The energy storage power supply system includes a high-voltage side grid-connected switch, an energy storage transformer, an energy storage converter device PCS, an energy storage unit, an NDC fast DC circuit breaker inside the energy storage system, a UPS output isolation transformer, and an NDC fast DC circuit breaker on the EMS side; the flywheel energy storage high-voltage side grid-connected switch is connected to the high-voltage plant bus; the energy storage converter device PCS is connected to the high-voltage side grid-connected switch via an energy storage transformer; the energy storage unit is connected to the energy storage converter device PCS via an NDC fast DC circuit breaker inside the energy storage system; The EMS system includes an EMS controller body, a plant power detection module, a 220V plant power bus, a secondary equipment cabinet, a bypass switch and a station DC bus; the EMS system exchanges communication information with the plant power detection module; the EMS system is connected to the energy storage converter through the EMS side NDC fast DC circuit breaker and the UPS output isolation transformer; the EMS system exchanges communication information with the energy storage converter PCS; the EMS system is connected to the 220V plant power bus; the 220V plant power bus is connected to the station DC bus through the bypass switch; the secondary equipment cabinet is connected to the EMS controller body through the station DC bus.

2. The energy storage system frequency regulation and UPS dual-function coordinated control system based on SOC partitioning according to claim 1 is characterized in that: The SOC interval set in the energy storage power supply system is divided into four sections: 0%-10% is a prohibited discharge area, 10%-20% is a UPS dedicated capacity area, 20%-80% is a frequency-modulated UPS dynamic sharing area, and 80%-100% is a prohibited charging area.

3. The energy storage system frequency regulation and UPS dual-function coordinated control method based on SOC partitioning is characterized by: The method is based on the SOC partition-based energy storage system frequency regulation and UPS dual-function coordinated control system described in claim 1, and includes: The auxiliary power detection module obtains auxiliary power status information, including auxiliary power voltage and frequency, from the EMS system. When an auxiliary power abnormality is detected (voltage drop ≤ 20% and frequency deviation ≤ ±0.5Hz), the NDC fast DC circuit breaker inside the energy storage system is disconnected, the NDC fast DC circuit breaker on the EMS side is closed, and the bypass switch is disconnected. The instantaneous power demand is calculated by real-time acquisition of the SOC status information of the energy storage system and transmitted to the energy storage unit. Simultaneously, the auxiliary power detection module monitors in real time whether the auxiliary power status has been restored. When the auxiliary power status has been restored, the NDC fast DC circuit breaker inside the energy storage system is closed, the NDC fast DC circuit breaker on the EMS side is disconnected, and the bypass switch is closed. The energy storage-assisted thermal power unit system is normally put into frequency regulation, and the DC bus in the station is powered by 220V auxiliary power. ABN(t) is the abnormal sign of factory power consumption; V grid is the factory power voltage; V rated is the rated voltage of the factory power supply; f grid The factory power frequency.

4. The method for coordinated control of energy storage system frequency modulation and UPS dual functions based on SOC partitioning according to claim 3 is characterized in that: When ABN(t) = 1, the auxiliary power system is in an abnormal state. The NDC fast DC circuit breaker inside the energy storage system is disconnected, the NDC fast DC circuit breaker on the EMS side is closed, and the bypass switch is disconnected.

5. The method for coordinated control of energy storage system frequency modulation and UPS dual functions based on SOC partitioning according to claim 3 is characterized in that: When ABN(t) = 0, the auxiliary power system is in normal condition. The NDC fast DC circuit breaker inside the energy storage system is closed, the NDC fast DC circuit breaker on the EMS side is opened, and the bypass switch is closed.

6. The method for coordinated control of energy storage system frequency modulation and UPS dual functions based on SOC partitioning according to claim 3 is characterized in that: When ABN(t)=1, the output power of the energy storage system changes according to the change of SOC, and the output power of the energy storage system is more stable; Among them, P ups P is the output power of the energy storage system when the plant power supply is abnormal, and P is the rated power of the UPS.

7. The method for coordinated control of energy storage system frequency modulation and UPS dual functions based on SOC partitioning according to claim 6 is characterized in that: When ABN(t)=0, the EMS system determines the differential power of the thermal power unit based on the difference between the AGC target power value of the unit issued by the dispatcher and the real-time active power of the corresponding thermal power unit, and determines the adjusted target power of each energy storage unit corresponding to the thermal power unit based on the differential power of the thermal power unit, the maximum adjustable power of the energy storage corresponding to the frequency regulation of the thermal power unit, and the active power adjustment dead zone parameter.

8. The method for coordinated control of energy storage system frequency regulation and UPS dual functions based on SOC partitioning according to claim 7 is characterized in that: When the difference power is within the dead zone of energy storage active power adjustment, the energy storage system does not output power; When the difference power exceeds the positive deviation dead zone and is less than the maximum dischargeable power of the energy storage, the energy storage output power is equal to the difference power; the internal unit power of the energy storage is distributed to the corresponding PCS in proportion to the dischargeable energy storage unit; When the difference power exceeds the positive deviation dead zone and is greater than the maximum dischargeable power of the energy storage, the energy storage outputs the maximum dischargeable power; the internal unit power of the energy storage is distributed to the corresponding PCS in proportion to the dischargeable energy storage unit; When the difference power exceeds the negative deviation dead zone and is greater than the maximum rechargeable power of the energy storage, the energy storage output power is equal to the difference power; the power of the internal unit of the energy storage is distributed to the corresponding PCS in proportion to the rechargeable energy storage unit; When the difference power exceeds the negative deviation dead zone range and is less than the maximum rechargeable power of the energy storage, the energy storage outputs the maximum rechargeable power; the power of the internal unit of the energy storage is distributed to the corresponding PCS in proportion to the rechargeable energy storage unit; When the maximum chargeable power of the energy storage is 0, the energy storage system will refuse to execute the charge instruction; when the maximum dischargeable power of the energy storage is 0, the energy storage system will refuse to execute the discharge instruction; in, is the target power adjustment of energy storage, σ n Adjust the dead zone parameter for the active power of energy storage, ΔP n is the difference power between the thermal power unit and the AGC instruction, is the maximum dischargeable power of energy storage; The maximum chargeable power of the energy storage.

9. The method for coordinated control of energy storage system frequency modulation and UPS dual functions based on SOC partitioning according to claim 8, characterized in that: Maximum discharge power of energy storage Is a positive value.

10. The method for coordinated control of energy storage system frequency regulation and UPS dual functions based on SOC partitioning according to claim 8, characterized in that: Maximum rechargeable power of energy storage is a negative value.

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