A user-side energy storage operation method and system

Abstract

The application discloses a user-side energy storage operation method and system. The user-side energy storage operation method comprises the following steps: acquiring a power supply guarantee period, a maximum grid-connected power limit value and maximum load power in the power supply guarantee period; in the power supply guarantee period, if the maximum load power in the power supply guarantee period is less than or equal to the maximum grid-connected power limit value, an energy storage system adopts a first operation mode; otherwise, the energy storage system adopts a second operation mode; in the second operation mode, it is judged whether the energy storage system meets preset charging and discharging conditions, and if yes, the energy storage system is charged or discharged. The application can realize the following: by setting the power supply guarantee period, comparing the maximum grid-connected power limit value in the power supply guarantee period with the maximum load power in the power supply guarantee period, determining the operation mode suitable for the energy storage system, realizing the fusion of the first operation mode and the second operation mode and the free switching, meeting the power supply guarantee demand of users and guaranteeing the economy of the project.

Description

Technical Field

[0001] This invention relates to the field of energy storage technology, and in particular to a user-side energy storage operation method and system. Background Technology

[0002] Recent changes in the power supply situation have presented challenges to the electricity business model. Specifically, in the third quarter of 2021, many provinces across the country implemented power rationing measures due to "dual control" restrictions. Taking Zhejiang and Jiangsu provinces as examples, their power rationing measures were based on an orderly power consumption plan. This meant that the power supply company would inform users one day in advance of the power rationing period and the limited power output to the grid the following day, and users' net load could not exceed this power limit. If a user repeatedly exceeded the grid limit, the power supply company would cut off their power.

[0003] Energy storage offers advantages such as large energy storage capacity and fast charging speed. Therefore, it plays a crucial role in ensuring power supply to users when restrictions are in place. Current energy storage operation modes typically involve users manually controlling the charging and discharging of energy storage based on actual load demand and real-time electricity prices. However, this method relies heavily on manual judgment and control of energy storage charging and discharging, resulting in poor power supply effectiveness and reliability. Furthermore, the cumbersome manual operation negatively impacts the efficiency of power supply assurance on the user side. Summary of the Invention

[0004] This invention provides a user-side energy storage operation method and system to achieve intelligent operation of energy storage under power curtailment policies, while meeting users' power supply needs and ensuring project economics.

[0005] According to one aspect of the present invention, a user-side energy storage operation method is provided, the user-side energy storage operation method comprising:

[0006] Obtain the guaranteed power supply period, the maximum power limit for grid disconnection, and the maximum load power within the guaranteed power supply period;

[0007] During the power supply guarantee period, if the maximum load power during the power supply guarantee period is less than or equal to the maximum limit of the grid-connected power, the energy storage system adopts the first operating mode; otherwise, the energy storage system adopts the second operating mode.

[0008] In the second operating mode, it is determined whether the energy storage system meets the preset charging and discharging conditions. If it does, the energy storage system is charged or discharged.

[0009] Optionally, in the second operating mode, determining whether the energy storage system meets preset charging and discharging conditions, and if so, charging or discharging the energy storage system, includes:

[0010] In the second operating mode, the current energy storage tracking power off the grid during the power supply guarantee period, the energy storage capacity required for the remaining power supply guarantee period, and the current remaining capacity of the energy storage system are obtained.

[0011] Based on the current power of the energy storage system tracking the grid during the power supply period and the maximum limit of the grid power, it is determined whether the preset discharge conditions are met. If they are met, the energy storage system is discharged.

[0012] Based on the energy storage capacity required for the remaining power supply period and the current remaining capacity of the energy storage system, it is determined whether the preset charging conditions are met. If they are met, the energy storage system is charged.

[0013] Optionally, determining whether the preset discharge conditions are met based on the current grid-connected power of the energy storage tracking system and the maximum limit of the grid-connected power during the power supply guarantee period includes:

[0014] Determine whether the current power of the energy storage tracking grid is greater than the maximum limit of the grid power during the power supply guarantee period; if so, discharge when the preset discharge power condition is met.

[0015] Optionally, discharging when a preset discharge power condition is met includes:

[0016] Obtain the maximum discharge power of the energy storage system;

[0017] Determine whether the difference between the current energy storage tracking power and the maximum limit of the power during the power supply period is less than or equal to the maximum discharge power of the energy storage system; if so, discharge at the first preset discharge power; otherwise, discharge at the second preset discharge power.

[0018] Optionally, the step of determining whether the preset charging conditions are met based on the required energy storage capacity for the remaining power supply period and the current remaining capacity of the energy storage system includes:

[0019] Determine whether the energy storage capacity required for the remaining power supply period is greater than the current remaining capacity of the energy storage system. If so, the energy storage system needs to be charged and will be charged when the preset charging power condition is met.

[0020] If not, then the need for charging of the energy storage system is determined based on the electricity price.

[0021] Optionally, charging when a preset charging power condition is met includes:

[0022] Obtain the maximum charging power of the energy storage system;

[0023] Determine whether the difference between the maximum power limit of the grid connection and the current power supply tracking grid connection during the power supply period is less than or equal to the maximum charging power of the energy storage system; if so, charge at the first preset charging power; otherwise, charge at the second preset charging power.

[0024] Optionally, determining whether the energy storage system needs charging based on electricity price includes:

[0025] Obtain the electricity price at the time the power supply guarantee period ends and the electricity price during the rechargeable period within the remaining power supply guarantee period;

[0026] Determine whether the price difference between the electricity price at the end of the guaranteed power supply period and the electricity price during the rechargeable period within the remaining guaranteed power supply period satisfies the arbitrage condition; if the arbitrage condition is satisfied, then the energy storage system is charged within the remaining guaranteed power supply period, and when the preset charging power condition is met; if the arbitrage condition is not satisfied, then the energy storage system is not charged.

[0027] Optionally, obtaining the maximum load power during the power supply guarantee period includes:

[0028] Obtained based on user input or historical load curves input by the user.

[0029] Optionally, outside of the power supply guarantee period, the first operating mode is adopted.

[0030] Optionally, the energy storage system is ensured to be fully charged before the power supply period begins.

[0031] Optionally, ensuring that the energy storage system is fully charged includes:

[0032] The shortest time required to fully charge the energy storage system is determined based on the charge / discharge rate of the energy storage system, and is recorded as the first time.

[0033] Obtain the duration of the nearest charging period before entering the power supply guarantee period, and record it as the second duration;

[0034] If the second duration is greater than or equal to the first duration, the energy storage system is fully charged within the second duration.

[0035] If the second duration is less than the first duration, the insufficient charging time will be supplemented by the period with the lowest electricity price before and after the second duration.

[0036] According to another aspect of the present invention, a user-side energy storage operation system is provided, the user-side energy storage operation system comprising:

[0037] The power supply guarantee period acquisition module is used to acquire the power supply guarantee period.

[0038] The module for obtaining the maximum power limit of the grid connection is used to obtain the maximum power limit of the grid connection.

[0039] The maximum load power acquisition module is used to acquire the maximum load power during the power supply guarantee period;

[0040] The module for determining the maximum load power and the maximum grid-connected power limit during the power supply guarantee period is used to determine whether the energy storage system adopts a first operating mode if the maximum load power during the power supply guarantee period is less than or equal to the maximum grid-connected power limit; otherwise, the energy storage system adopts a second operating mode.

[0041] The energy storage charging and discharging judgment module is used to determine whether the energy storage system meets the preset charging and discharging conditions in the second operating mode. If the conditions are met, the energy storage system is charged or discharged.

[0042] The technical solution of this invention provides a user-side energy storage operation method and system. The method includes: acquiring the power supply guarantee period, the maximum grid connection power limit, and the maximum load power within the power supply guarantee period; within the power supply guarantee period, if the maximum load power is less than or equal to the maximum grid connection power limit, the energy storage system adopts a first operation mode; otherwise, the energy storage system adopts a second operation mode; in the second operation mode, it is determined whether the energy storage system meets preset charging and discharging conditions; if so, the energy storage system is charged or discharged. This operation method achieves the following: by setting a power supply guarantee period and comparing the maximum grid connection power limit with the maximum load power within the power supply guarantee period to determine a suitable operation mode for the energy storage system, the first and second operation modes can be integrated and freely switched. Furthermore, in the second operation mode, the energy storage system is charged or discharged when the preset charging and discharging conditions are met, thus satisfying the user's power supply needs, ensuring the project's economic viability, and providing convenience for use.

[0043] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0044] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0045] Figure 1This is a flowchart of a user-side energy storage operation method provided in an embodiment of the present invention;

[0046] Figure 2 This is a schematic diagram of a first operating mode provided in an embodiment of the present invention;

[0047] Figure 3 This is a flowchart of another user-side energy storage operation method provided in this embodiment of the invention;

[0048] Figure 4 This is a schematic diagram of an energy storage charging and discharging operation state that integrates a first operating mode and a second operating mode, provided in an embodiment of the present invention.

[0049] Figure 5 This is a schematic diagram of a multi-segment power supply system provided in an embodiment of the present invention;

[0050] Figure 6 This is a structural block diagram of a user-side energy storage operation system provided in an embodiment of the present invention. Detailed Implementation

[0051] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0052] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0053] Figure 1This is a flowchart illustrating a user-side energy storage operation method provided in this embodiment of the invention. This embodiment is applicable to energy storage operation methods in power system processing platforms that meet user-side power supply needs while ensuring project economics. This method can be executed by a user-side energy storage operation device, which can be implemented in hardware and / or software and can be configured in the server of the power system processing platform. Figure 1 As shown, the method includes:

[0054] Step 110: Obtain the power supply guarantee period, the maximum power limit for grid disconnection, and the maximum load power within the power supply guarantee period.

[0055] In this context, "power supply guarantee" refers to providing sufficient power to the user's load to ensure their electricity consumption. Users can set the start and end times of the power supply guarantee period according to power rationing policies. Furthermore, multiple power supply guarantee periods can be set based on actual circumstances.

[0056] The maximum power limit for grid connection refers to the maximum power that the power grid can provide, and its value is related to the power supply capacity of the power grid and power supply policies. The maximum load power during the guaranteed power supply period is the maximum allowable load power on the user side during the guaranteed power supply period.

[0057] Step 120: Determine whether the maximum load power during the power supply guarantee period is less than or equal to the maximum power limit of the grid connection. If yes, proceed to step 130; otherwise, proceed to step 140.

[0058] Specifically, if the maximum load power during the power supply guarantee period is less than or equal to the maximum grid power limit, it means that the grid power supply can meet the user's load demand, and the energy storage system does not need to guarantee power supply. Therefore, the energy storage system can operate in the first operating mode. However, if the maximum load power during the power supply guarantee period is greater than the maximum grid power limit, it means that the grid power supply cannot meet the user's load demand, and the energy storage system needs to participate in the power supply guarantee to ensure that the user's power supply needs are met.

[0059] Step 130: The energy storage system adopts the first operating mode.

[0060] Figure 2 This is a schematic diagram of a first operating mode provided in an embodiment of the present invention. (Reference) Figure 2 For example, taking the time-of-use electricity pricing of a large industrial company outside of July and August as an example, there are three types of electricity prices within a day: off-peak, flat, and peak. Taking an energy storage system with a 0.5C charge / discharge rate as an example, such as... Figure 2The energy storage system charges to full capacity at a certain power from 10 PM to 8 AM the next day (assuming the charging power is negative and the discharging power is positive). During the first peak period from 9 AM to 11 AM, it discharges to empty by tracking the load power. It is fully charged again during the second off-peak period from 11 AM to 1 PM, and then discharges to empty by tracking the load power during the second peak period from 3 PM to 5 PM. In this way, the energy storage system completes the first operating mode of two charges and two discharges within one day.

[0061] Step 140: The energy storage system adopts the second operating mode.

[0062] In the second operating mode, the energy storage system, through reasonable charging and discharging, can support the load power on the user side during the power rationing period without exceeding the maximum power limit of the grid, thereby ensuring the power supply on the user side.

[0063] Step 150: In the second operating mode, determine whether the energy storage system meets the preset charging and discharging conditions. If it does, charge or discharge the energy storage system.

[0064] In the second operating mode, by determining whether the energy storage system meets the preset charging and discharging conditions, the energy storage system is charged and discharged in a reasonable manner to meet the load demand on the user side, thereby achieving better economic efficiency while ensuring power supply.

[0065] In this embodiment, the working principle of the user-side energy storage operation method is as follows: First, the power supply guarantee period, the maximum grid power limit, and the maximum load power within the power supply guarantee period are obtained. Then, within the power supply guarantee period, if the maximum load power within the power supply guarantee period is less than or equal to the maximum grid power limit, the energy storage system adopts a first operating mode; otherwise, the energy storage system adopts a second operating mode. Finally, in the second operating mode, it is determined whether the energy storage system meets the preset charging and discharging conditions. If it does, the energy storage system is charged or discharged. Therefore, by setting a power supply guarantee period according to power rationing policies, and if the maximum grid power limit within the power supply guarantee period can meet the user's load demand, the energy storage system adopts the first operating mode, fully leveraging its advantages. If the maximum grid power limit cannot meet the user's load demand, the energy storage system adopts the second operating mode, and within the second operating mode, reasonable charging and discharging operation of the energy storage system is achieved according to the preset charging and discharging conditions, thereby improving economic efficiency while ensuring power supply. Therefore, by integrating the first and second operating modes, the advantages of both modes can be fully utilized to ensure power supply while improving the project's economic efficiency. Furthermore, the mode can be switched freely through automatic judgment, and the entire operation process requires no manual intervention, thereby improving the efficiency and ease of use of the energy storage system.

[0066] The technical solution of this embodiment provides a user-side energy storage operation method. This method includes: obtaining the guaranteed power supply period, the maximum grid connection power limit, and the maximum load power within the guaranteed power supply period; within the guaranteed power supply period, if the maximum load power is less than or equal to the maximum grid connection power limit, the energy storage system adopts a first operation mode; otherwise, the energy storage system adopts a second operation mode; in the second operation mode, it is determined whether the energy storage system meets preset charging and discharging conditions; if so, the energy storage system is charged or discharged. This operation method achieves the following: by setting a guaranteed power supply period and comparing the maximum grid connection power limit with the maximum load power within the guaranteed power supply period to determine the appropriate operation mode for the energy storage system, the first and second operation modes can be integrated and freely switched. Furthermore, in the second operation mode, the energy storage system is charged or discharged when the preset charging and discharging conditions are met, thus satisfying the user's guaranteed power supply needs, ensuring the project's economic viability, and providing convenience for use.

[0067] Figure 3 This is a flowchart of another user-side energy storage operation method provided in this embodiment of the invention. Figure 4 This is a schematic diagram of an energy storage charging and discharging operation state that integrates a first operating mode and a second operating mode, provided by an embodiment of the present invention. Optionally, as one implementation, refer to... Figure 3 The method includes:

[0068] Step 210: Obtain the power supply guarantee period, the maximum power limit for grid disconnection, and the maximum load power within the power supply guarantee period.

[0069] Step 220: Determine whether the maximum load power during the power supply guarantee period is less than or equal to the maximum power limit for grid disconnection. If yes, proceed to step 230; otherwise, proceed to step 240.

[0070] Step 230: The energy storage system adopts the first operating mode.

[0071] Step 240: The energy storage system adopts the second operating mode.

[0072] Step 250: In the second operating mode, obtain the current energy storage tracking power during the power supply guarantee period, the energy storage capacity required for the remaining power supply guarantee period, and the current remaining capacity of the energy storage system.

[0073] Among them, the current power of energy storage tracking during the power supply guarantee period refers to the total power that the entire system needs to generate in real time, including the real-time load power on the user side and the real-time power of the energy storage system.

[0074] Since the start and end times of the power supply guarantee period are known, the remaining power supply guarantee period can be determined. Then, based on the maximum grid connection power limit, the maximum load power within the power supply guarantee period, and the remaining power supply guarantee period, the required energy storage capacity for the remaining power supply guarantee period can be determined. For example, assume the remaining power supply guarantee period is T. 保剩 If the maximum power supply limit is A, and the maximum load power during the power supply guarantee period is D, then the required energy storage capacity Q for the remaining power supply guarantee period is... 需 for:

[0075] Q 需 = (DA)×T 保剩

[0076] The current remaining capacity of the energy storage system refers to its real-time remaining capacity. This real-time remaining capacity allows for the estimation of the remaining operational time of the energy storage system and can be used for real-time querying as a basis for load adjustment. Assume the current remaining capacity of the energy storage system is Q. 储剩 Then the remaining working time of the energy storage system is T. 储剩 :

[0077]

[0078] Step 260: Determine whether the preset discharge conditions are met based on the current grid-connected power and the maximum grid-connected power limit during the power supply period. If they are met, discharge the energy storage system.

[0079] If the current grid-connected power and the maximum grid-connected power limit of the energy storage system meet the preset discharge conditions during the power supply period, it means that the power supply of the grid cannot meet the load demand of the user side, and the energy storage system needs to discharge to ensure the power supply demand of the user side. At this time, the operating state of the energy storage system is the discharge state.

[0080] Step 270: Determine whether the preset charging conditions are met based on the energy storage capacity required for the remaining power supply period and the current remaining capacity of the energy storage system. If they are met, charge the energy storage system.

[0081] If the energy storage capacity required for the remaining power supply period and the current remaining capacity of the energy storage system meet the preset charging conditions, it means that the current remaining capacity of the energy storage system cannot continue to maintain the energy required for the remaining power supply period. At this time, the energy storage system needs to be charged, and the operating state of the energy storage system is the charging state.

[0082] As a specific implementation method, optionally, it is determined whether the preset discharge conditions are met based on the current grid-connected power of the energy storage tracking and the maximum limit of the grid-connected power during the power supply guarantee period, including:

[0083] Determine whether the current grid-connected power of the energy storage system during the power supply guarantee period is greater than the maximum grid-connected power limit; if so, discharge when the preset discharge power condition is met.

[0084] Specifically, if the current grid-connected power of the energy storage system exceeds the maximum grid-connected power limit during the power supply period, it indicates that the grid power supply cannot meet the load demand of the user side, and the energy storage system needs to discharge to ensure the power supply demand of the user side. To ensure the reliability of the energy storage system's discharge, it is necessary to further determine whether the current situation meets the preset discharge power conditions. Only when the preset discharge power conditions are met can the energy storage system be discharged.

[0085] Optionally, discharging when a preset discharge power condition is met includes:

[0086] To obtain the maximum discharge power of the energy storage system;

[0087] Determine whether the difference between the current energy storage tracking power and the maximum limit of the power to be discharged from the grid during the power supply guarantee period is less than or equal to the maximum discharge power of the energy storage system; if so, discharge at the first preset discharge power; otherwise, discharge at the second preset discharge power.

[0088] The first preset discharge power is the difference between the current energy storage tracking power and the maximum limit of the grid power during the power supply guarantee period. At this time, the difference between the current energy storage tracking power and the maximum limit of the grid power during the power supply guarantee period is the total power required by the energy storage system to discharge and supplement the user-side load, which is also the power that the grid cannot supply to the user-side load. The second preset discharge power is the maximum discharge power of the energy storage system.

[0089] Specifically, the system determines whether the current grid-connected power of the energy storage system during the power supply guarantee period exceeds the maximum grid-connected power limit. If so, it indicates that the grid power supply cannot meet the user's load demand, and the energy storage system needs to discharge to ensure the user's power supply needs. Furthermore, to ensure the reliability of the energy storage system's discharge, the system determines whether the difference between the current grid-connected power and the maximum grid-connected power limit during the power supply guarantee period is less than or equal to the energy storage system's maximum discharge power. If so, it indicates that the total power required by the energy storage system to supplement the user's load is less than its maximum discharge power requirement, and it can discharge at the first preset discharge power. Otherwise, it indicates that the total power required by the energy storage system to supplement the user's load exceeds its maximum discharge power requirement, and it discharges at the energy storage system's maximum discharge power. Thus, while meeting the energy storage system's discharge power requirements, it can simultaneously deliver power insufficient for grid supply to the user, thereby meeting the user's power supply guarantee needs.

[0090] As a specific implementation method, optionally, determining whether the preset charging conditions are met based on the energy storage capacity required for the remaining power supply period and the current remaining capacity of the energy storage system includes:

[0091] Determine whether the energy storage capacity required for the remaining power supply period is greater than the current remaining capacity of the energy storage system. If so, the energy storage system needs to be charged and will be charged when the preset charging power condition is met.

[0092] If not, then the need for charging of the energy storage system is determined based on the electricity price.

[0093] Specifically, if the energy storage capacity required for the remaining power supply period is greater than the current remaining capacity of the energy storage system, it means that the current remaining capacity of the energy storage system is insufficient to sustain the energy required for the remaining power supply period, and the energy storage system needs to be charged. To ensure the reliability of the energy storage system's charging, it is necessary to further determine whether the current situation meets the preset charging power conditions. Only if the preset charging power conditions are met can the energy storage system be charged. If the energy storage capacity required for the remaining power supply period is less than the current remaining capacity of the energy storage system, it means that the current remaining capacity of the energy storage system is sufficient to meet the energy requirements for the remaining power supply period, and the energy storage system is neither charged nor not charged. This period is defined as the rechargeable period. To maximize economic benefits, the time-of-use electricity price at the end of the power supply period should be considered to determine whether charging is necessary. For example, the need for charging can be determined based on the electricity price.

[0094] Optionally, charging when a preset charging power condition is met includes:

[0095] Obtain the maximum charging power of the energy storage system;

[0096] Determine whether the difference between the maximum power limit of the grid connection and the current power of the energy storage tracking grid connection during the power supply guarantee period is less than or equal to the maximum charging power of the energy storage system; if so, charge at the first preset charging power; otherwise, charge at the second preset charging power.

[0097] The first preset charging power is the difference between the maximum power limit of the grid connection and the current grid connection power of the energy storage system during the power supply guarantee period. At this time, the difference between the maximum power limit of the grid connection and the current grid connection power of the energy storage system during the power supply guarantee period is the power that the grid can provide to the energy storage system for charging. The second preset charging power is the maximum charging power of the energy storage system.

[0098] Specifically, it is determined whether the energy storage capacity required for the remaining power supply period is greater than the current remaining capacity of the energy storage system. If so, it indicates that the current remaining capacity of the energy storage system is insufficient to sustain the energy required for the remaining power supply period. Furthermore, if the current grid-connected power tracking power during the power supply period is less than the maximum grid-connected power limit, the energy storage system needs to be charged. To ensure the reliability of the energy storage system's charging, it is determined whether the difference between the maximum grid-connected power limit and the current grid-connected power tracking power during the power supply period is less than or equal to the maximum charging power of the energy storage system. If so, it indicates that the grid can provide the energy storage system with the power required for charging, and charging is performed at the first preset charging power. Otherwise, it indicates that the grid can provide the energy storage system with the power required for charging, meeting the maximum charging power requirement of the energy storage system, and charging is performed at the maximum charging power of the energy storage system. Thus, the charging power requirement of the energy storage system can be met while simultaneously ensuring reliable power supply. If the energy storage capacity required for the remaining power supply period is less than the current remaining capacity of the energy storage system, it indicates that the current remaining capacity of the energy storage system is sufficient to meet the energy requirements for the remaining power supply period. In this case, the energy storage system is neither charged nor not charged, and this period is defined as a rechargeable period. To maximize economic benefits, the time-of-use pricing when the power supply period ends should be considered when deciding whether charging is necessary.

[0099] Optionally, the need for charging of the energy storage system can be determined based on the electricity price, including:

[0100] Obtain the electricity price when the guaranteed power supply period ends and the electricity price during the rechargeable period within the remaining guaranteed power supply period;

[0101] Determine whether the price difference between the electricity price at the end of the guaranteed power supply period and the electricity price during the charging period within the remaining guaranteed power supply period satisfies the arbitrage conditions. If the arbitrage conditions are met, the energy storage system will be charged within the remaining guaranteed power supply period, provided that the preset charging power conditions are met. If the arbitrage conditions are not met, the energy storage system will not be charged.

[0102] The electricity price at the end of the guaranteed power supply period and the electricity price during the charging period within the remaining guaranteed power supply period can be obtained from the power grid price system.

[0103] Specifically, when the electricity price at the end of the guaranteed power supply period is higher than the electricity price during the rechargeable periods within the remaining guaranteed power supply period, and the price difference meets the arbitrage conditions, the energy storage system charges during the rechargeable periods within the remaining guaranteed power supply period. Furthermore, the system is charged when the preset charging power conditions are met, until the energy storage system is fully charged. The advantage of this setup is that after immediately entering the first operating mode following the end of the guaranteed power supply period, it can immediately begin discharging (e.g., ...). Figure 4 As shown, the system discharges after the guaranteed power supply period ends, thus improving economic efficiency. If the price difference between the electricity price at the end of the guaranteed power supply period and the price during the rechargeable period within the remaining guaranteed power supply period does not meet the arbitrage conditions, the energy storage system will not charge, such as... Figure 4 The remaining power supply period T shown 保剩 Not charging.

[0104] Optionally, the maximum load power during the power supply guarantee period can be obtained, including:

[0105] Obtained based on user input or historical load curves input by the user.

[0106] The maximum load power during the guaranteed power supply period can be a user-input parameter, which essentially assumes a constant load. To improve calculation accuracy, the maximum load power during the guaranteed power supply period can also be a load function derived from the user-input historical load curve or using predictive amplification, such as D(t). Correspondingly, the current remaining capacity of the energy storage system can be obtained as Q. 储剩 :

[0107]

[0108] Energy storage capacity Q required for the remaining power supply period 需 :

[0109]

[0110] It should be noted that the load described in any embodiment of the present invention can also be a net load concept that includes photovoltaics. Therefore, the user-side energy storage operation method provided in the embodiments of the present invention can also be applied to user-side photovoltaic-energy storage scenarios.

[0111] Figure 5 This is a schematic diagram of a multi-period power supply guarantee system provided in an embodiment of the present invention. Optionally, outside the power supply guarantee period, a first operating mode is adopted.

[0112] refer to Figure 5 For example, within a certain time period, such as 24 hours a day, multiple power supply guarantee periods can be set. Within each guarantee period, the application of either the first or second operating mode is determined by assessing the maximum load power and the maximum grid connection power limit. Outside of the guarantee periods, the first operating mode is used exclusively. Thus, by integrating the peak-valley arbitrage operating mode with the second operating mode and allowing for flexible switching, the user's power supply needs are met, the project's economic viability is ensured, and ease of use is provided.

[0113] Optionally, ensure that the energy storage system is fully charged before entering the power supply guarantee period.

[0114] Before entering the power supply guarantee period, the energy storage system is fully charged at the most economical cost. This allows the fully charged energy storage system to directly enter the discharge operation mode when the system needs to discharge or when the preset discharge conditions are met, thus achieving power supply guarantee while improving economic efficiency.

[0115] Optionally, ensuring the energy storage system is fully charged includes:

[0116] The shortest time required to fully charge the energy storage system is determined based on the charge / discharge rate of the energy storage system, and is recorded as the first time.

[0117] Obtain the duration of the nearest charging period before entering the power supply guarantee period, and record it as the second duration;

[0118] If the second duration is greater than or equal to the first duration, the energy storage system will be fully charged within the second duration.

[0119] If the second duration is shorter than the first duration, the insufficient charging time will be supplemented by the period with the lowest electricity price before and after the second duration.

[0120] For example, refer to Figure 4 Let the first duration be T1 and the second duration be T2. Assuming the charge / discharge rate of the energy storage system is 0.5C, the formula for determining the first duration T1 based on the charge / discharge rate of the energy storage system is as follows:

[0121]

[0122] The second duration, T2, typically represents off-peak or grid-rate periods, and can be considered a period with low electricity prices. Figure 4 As shown. If the second duration T2 is greater than or equal to the first duration T1, it means that the duration of the nearest charging period (low electricity price period) before entering the power supply guarantee period is sufficient to fully charge the energy storage system. Since the second duration T2 is usually a low-price or off-peak period with relatively low electricity prices, fully charging the energy storage system within the second duration T2 is also economically efficient. If the second duration T2 is less than the first duration T1, it means that the duration of the nearest charging period (low electricity price period) before entering the power supply guarantee period is insufficient to fully charge the energy storage system. The insufficient charging time is then supplemented by the lowest electricity price periods before and after the second duration T2. ​​For example, there are... Figure 4 The T2 period, which is the charging period before the guaranteed power supply period, refers to the period from 3 AM to 5 AM. This allows the energy storage system to be fully charged in a more economical way before the guaranteed power supply period begins, thus providing better cost-effectiveness while ensuring its power supply function during the guaranteed power supply period.

[0123] In this embodiment, the working principle of the user-side energy storage operation method is as follows: The power supply guarantee period, the maximum grid connection power limit, and the maximum load power within the power supply guarantee period are obtained. Outside the power supply guarantee period, the energy storage system adopts a first operating mode. Before entering each power supply guarantee period, the energy storage system is ensured to be fully charged. Within each power supply guarantee period, if the maximum load power within the power supply guarantee period is less than or equal to the maximum grid connection power limit, the energy storage system adopts the first operating mode; otherwise, the energy storage system adopts a second operating mode. In the second operating mode, it is determined whether the current grid connection power tracked by the energy storage system within the power supply guarantee period is greater than the maximum grid connection power limit. If so, it indicates that the grid power supply cannot meet the user-side load demand, and the energy storage system needs to discharge to ensure the user-side power supply demand. Furthermore, to ensure the reliability of the energy storage system's discharge, it is determined whether the difference between the current energy storage tracking power and the maximum limit of the grid power during the power supply guarantee period is less than or equal to the maximum discharge power of the energy storage system. If so, it indicates that the total power required by the energy storage system to supplement the user-side load is less than its maximum discharge power requirement, and discharge can proceed at the first preset discharge power. Otherwise, it indicates that the total power required by the energy storage system to supplement the user-side load exceeds its maximum discharge power requirement, and discharge can proceed at the maximum discharge power of the energy storage system. Simultaneously, in the second operating mode, it is determined whether the energy storage capacity required for the remaining power supply guarantee period is greater than the current remaining capacity of the energy storage system. If so, it indicates that the current remaining capacity of the energy storage system is insufficient to maintain the energy required for the remaining power supply guarantee period. Furthermore, if the current energy storage tracking power during the power supply guarantee period is less than the maximum limit of the grid power, the energy storage system needs to be charged. To ensure the reliability of energy storage system charging, it is determined whether the difference between the maximum grid power limit and the current grid power tracked by the energy storage system during the guaranteed power supply period is less than or equal to the maximum charging power of the energy storage system. If so, it means that the grid can provide the energy storage system with the power required for charging, and charging is performed at the first preset charging power. Otherwise, it means that the grid can provide the energy storage system with the power required for charging, which meets the maximum charging power requirement of the energy storage system, and charging is performed at the maximum charging power of the energy storage system. If the energy storage capacity required for the remaining guaranteed power supply period is less than the current remaining capacity of the energy storage system, it means that the current remaining capacity of the energy storage system can fully meet the energy requirements for the remaining guaranteed power supply period. In this case, the energy storage system is not charged, and this period is defined as a rechargeable period. To maximize economic benefits, the time-of-use electricity price at the end of the guaranteed power supply period should be considered to determine whether charging is necessary. Therefore, by setting guaranteed power supply periods and taking special considerations for the three stages of entering, operating, and exiting the guaranteed power supply period, the overall economic efficiency is improved.Furthermore, during periods of guaranteed power supply and during periods of non-guaranteed power supply, the first operating mode and the second operating mode can be integrated and switched freely, which expands the scope of application, meets the power supply needs of users, ensures the economic efficiency of the project, and brings convenience to use.

[0124] Figure 6 This is a structural block diagram of a user-side energy storage operation system provided in an embodiment of the present invention. Optionally, refer to... Figure 6 The user-side energy storage operation system 100 includes:

[0125] The power supply guarantee period acquisition module 10 is used to acquire the power supply guarantee period.

[0126] The module 20 for obtaining the maximum power limit of the grid connection is used to obtain the maximum power limit of the grid connection.

[0127] Maximum load power acquisition module 30 is used to acquire the maximum load power during the guaranteed power supply period;

[0128] The maximum load power and the maximum grid power limit judgment module 40 during the power supply guarantee period are used to determine whether the energy storage system adopts the first operating mode if the maximum load power during the power supply guarantee period is less than or equal to the maximum grid power limit; otherwise, the energy storage system adopts the second operating mode.

[0129] The energy storage charging and discharging judgment module 50 is used to determine whether the energy storage system meets the preset charging and discharging conditions in the second operating mode. If it does, the energy storage system is charged or discharged.

[0130] The technical solution of this embodiment provides a user-side energy storage operation system, which includes: a power supply guarantee period acquisition module for acquiring power supply guarantee periods; a grid connection power maximum limit acquisition module for acquiring grid connection power maximum limit; a maximum load power acquisition module for acquiring maximum load power during the power supply guarantee period; an energy storage operation mode determination module for determining whether the energy storage system adopts a first operation mode if the maximum load power during the power supply guarantee period is less than or equal to the grid connection power maximum limit; otherwise, the energy storage system adopts a second operation mode; and an energy storage charge / discharge determination module for determining whether the energy storage system meets preset charge / discharge conditions in the second operation mode, and charging or discharging the energy storage system if it does. This operating system enables the following: by setting a power supply guarantee period and comparing the maximum power output to the grid during the guarantee period with the maximum load power during the guarantee period, the system determines the appropriate operating mode for the energy storage system. This allows for the integration of the first and second operating modes with seamless switching. In the second operating mode, the energy storage system is charged or discharged when preset charging and discharging conditions are met. This satisfies the user's power supply guarantee needs, ensures the project's economic viability, and provides convenience for users.

[0131] Optionally, the energy storage charge / discharge determination module 50 also includes:

[0132] The current energy storage tracking grid-connected power acquisition unit is used to acquire the current energy storage tracking grid-connected power during the power supply guarantee period in the second operating mode;

[0133] The remaining time period required energy storage capacity acquisition unit is used to acquire the energy storage capacity required for the remaining time period of power supply in the second operating mode;

[0134] The current remaining capacity acquisition unit is used to acquire the current remaining capacity of the energy storage system in the second operating mode;

[0135] The energy storage discharge judgment unit is used to determine whether the preset discharge conditions are met based on the current energy storage tracking power and the maximum limit of the power during the power supply period. If the conditions are met, the energy storage system is discharged.

[0136] The energy storage charging judgment unit is used to determine whether the preset charging conditions are met based on the energy storage capacity required for the remaining power supply period and the current remaining capacity of the energy storage system. If the conditions are met, the energy storage system is charged.

[0137] Optionally, the energy storage discharge judgment unit is used to determine whether the current energy storage tracking power is greater than the maximum power limit during the power supply period; if so, it discharges when the preset discharge power condition is met.

[0138] Optionally, discharging when a preset discharge power condition is met includes:

[0139] To obtain the maximum discharge power of the energy storage system;

[0140] Determine whether the difference between the current energy storage tracking power and the maximum limit of the power to be discharged from the grid during the power supply guarantee period is less than or equal to the maximum discharge power of the energy storage system; if so, discharge at the first preset discharge power; otherwise, discharge at the second preset discharge power.

[0141] Optionally, the energy storage charging judgment unit is used to determine whether the energy storage capacity required for the remaining power supply period is greater than the current remaining capacity of the energy storage system. If so, the energy storage system needs to be charged and will be charged when the preset charging power condition is met.

[0142] If not, then the need for charging of the energy storage system is determined based on the electricity price.

[0143] Optionally, charging when a preset charging power condition is met includes:

[0144] Obtain the maximum charging power of the energy storage system;

[0145] Determine whether the difference between the maximum power limit of the grid connection and the current power of the energy storage tracking grid connection during the power supply period is less than or equal to the maximum charging power of the energy storage system; if so, charge at the first preset charging power; otherwise, charge at the second preset charging power.

[0146] Optionally, the need for charging of the energy storage system can be determined based on the electricity price, including:

[0147] Obtain the electricity price when the guaranteed power supply period ends and the electricity price during the rechargeable period within the remaining guaranteed power supply period;

[0148] Determine whether the price difference between the electricity price at the end of the guaranteed power supply period and the electricity price during the charging period within the remaining guaranteed power supply period satisfies the arbitrage conditions. If the arbitrage conditions are met, the energy storage system will be charged within the remaining guaranteed power supply period, provided that the preset charging power conditions are met. If the arbitrage conditions are not met, the energy storage system will not be charged.

[0149] Optionally, the maximum load power during the power supply guarantee period can be obtained, including:

[0150] Obtained based on user input or historical load curves input by the user.

[0151] Optionally, outside of the power supply guarantee period, the first operating mode can be adopted.

[0152] Optionally, ensure that the energy storage system is fully charged before entering the power supply guarantee period.

[0153] Optionally, ensuring the energy storage system is fully charged includes:

[0154] The shortest time required to fully charge the energy storage system is determined based on the charge / discharge rate of the energy storage system, and is recorded as the first time.

[0155] Obtain the duration of the nearest charging period before entering the power supply guarantee period, and record it as the second duration;

[0156] If the second duration is greater than or equal to the first duration, the energy storage system will be fully charged within the second duration.

[0157] If the second duration is shorter than the first duration, the insufficient charging time will be supplemented by the period with the lowest electricity price before and after the second duration.

[0158] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0159] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A user-side energy storage operation method, characterized in that, include: Obtain the guaranteed power supply period, the maximum power limit for grid disconnection, and the maximum load power within the guaranteed power supply period; During the power supply guarantee period, if the maximum load power during the power supply guarantee period is less than or equal to the maximum limit of the grid-connected power, the energy storage system adopts the first operating mode; otherwise, the energy storage system adopts the second operating mode. In the second operating mode, it is determined whether the energy storage system meets the preset charging and discharging conditions. If it does, the energy storage system is charged or discharged. In the second operating mode, it is determined whether the energy storage system meets preset charging and discharging conditions. If so, the energy storage system is discharged, including: In the second operating mode, the current energy storage tracking power off the grid during the power supply guarantee period, the energy storage capacity required for the remaining power supply guarantee period, and the current remaining capacity of the energy storage system are obtained. Based on the current power of the energy storage system tracking the grid during the power supply period and the maximum limit of the grid power, it is determined whether the preset discharge conditions are met. If they are met, the energy storage system is discharged. The step of determining whether the preset discharge conditions are met based on the current energy storage tracking power and the maximum limit of the power supply during the power supply period includes: Determine whether the current power of the energy storage tracking grid is greater than the maximum limit of the grid power during the power supply guarantee period; if so, discharge when the preset discharge power condition is met. 2.The user-side energy storage operation method according to claim 1, characterized in that, In the second operating mode, determining whether the energy storage system meets preset charging and discharging conditions, and if so, charging the energy storage system, includes: Based on the energy storage capacity required for the remaining power supply period and the current remaining capacity of the energy storage system, it is determined whether the preset charging conditions are met. If they are met, the energy storage system is charged. 3.The user-side energy storage operation method according to claim 1, characterized in that, The discharge when the preset discharge power condition is met includes: Obtain the maximum discharge power of the energy storage system; Determine whether the difference between the current energy storage tracking power and the maximum limit of the power during the power supply period is less than or equal to the maximum discharge power of the energy storage system; if so, discharge at the first preset discharge power; otherwise, discharge at the second preset discharge power. 4.The user-side energy storage operation method according to claim 2, characterized in that, The step of determining whether the preset charging conditions are met based on the energy storage capacity required for the remaining power supply period and the current remaining capacity of the energy storage system includes: Determine whether the energy storage capacity required for the remaining power supply period is greater than the current remaining capacity of the energy storage system. If so, the energy storage system needs to be charged and will be charged when the preset charging power condition is met. If not, then the need for charging of the energy storage system is determined based on the electricity price.

5. The user-side energy storage operation method according to claim 4, characterized in that, The charging when the preset charging power condition is met includes: Obtain the maximum charging power of the energy storage system; Determine whether the difference between the maximum power limit of the grid connection and the current power supply tracking grid connection during the power supply period is less than or equal to the maximum charging power of the energy storage system; if so, charge at the first preset charging power; otherwise, charge at the second preset charging power.

6. The user-side energy storage operation method according to claim 4, characterized in that, The step of determining whether the energy storage system needs charging based on electricity price includes: Obtain the electricity price at the time the power supply guarantee period ends and the electricity price during the rechargeable period within the remaining power supply guarantee period; Determine whether the price difference between the electricity price at the end of the guaranteed power supply period and the electricity price during the rechargeable period within the remaining guaranteed power supply period satisfies the arbitrage condition; if the arbitrage condition is satisfied, then the energy storage system is charged within the remaining guaranteed power supply period, and when the preset charging power condition is met; if the arbitrage condition is not satisfied, then the energy storage system is not charged. 7.The user-side energy storage operation method according to claim 1, characterized in that, The process of obtaining the maximum load power during the power supply guarantee period includes: Obtained based on user input or historical load curves input by the user. 8.The user-side energy storage operation method according to claim 1, characterized in that, Outside of the guaranteed power supply period, the first operating mode is adopted. 9.The user-side energy storage operation method according to claim 1, characterized in that, Before entering the power supply guarantee period, ensure that the energy storage system is fully charged.

10. The user-side energy storage operation method according to claim 9, characterized in that, Ensuring that the energy storage system is fully charged includes: The shortest time required to fully charge the energy storage system is determined based on the charge / discharge rate of the energy storage system, and is recorded as the first time. Obtain the duration of the nearest charging period before entering the power supply guarantee period, and record it as the second duration; If the second duration is greater than or equal to the first duration, the energy storage system is fully charged within the second duration. If the second duration is less than the first duration, the insufficient charging time will be supplemented by the period with the lowest electricity price before and after the second duration.

11. A user-side energy storage operation system, characterized in that, include: The power supply guarantee period acquisition module is used to acquire the power supply guarantee period. The module for obtaining the maximum power limit of the grid connection is used to obtain the maximum power limit of the grid connection. The maximum load power acquisition module is used to acquire the maximum load power during the power supply guarantee period; The module for determining the maximum load power and the maximum grid-connected power limit during the power supply guarantee period is used to determine whether the energy storage system adopts a first operating mode if the maximum load power during the power supply guarantee period is less than or equal to the maximum grid-connected power limit; otherwise, the energy storage system adopts a second operating mode. The energy storage charging and discharging judgment module is used to determine whether the energy storage system meets the preset charging and discharging conditions in the second operating mode. If the conditions are met, the energy storage system is charged or discharged. The energy storage charging and discharging determination module further includes: The current energy storage tracking power acquisition unit is used to acquire the current energy storage tracking power during the power supply guarantee period in the second operating mode. The remaining time period required energy storage capacity acquisition unit is used to acquire the energy storage capacity required for the remaining time period of power supply in the second operating mode; The current remaining capacity acquisition unit is used to acquire the current remaining capacity of the energy storage system in the second operating mode; The energy storage discharge judgment unit is used to determine whether the preset discharge conditions are met based on the current energy storage tracking power and the maximum limit of the power during the power supply period. If the conditions are met, the energy storage system is discharged. The energy storage discharge judgment unit is specifically used to determine whether the current energy storage tracking power during the power supply period is greater than the maximum power limit of the power supply; if so, it discharges when the preset discharge power condition is met.

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