Energy storage control method and system

Abstract

The invention discloses an energy storage control method and system. According to the embodiment of the invention, through the charge and discharge control of the plurality of UPS systems of the data center, the surplus capacity of the storage battery pack is utilized to carry out peak-valley arbitrage, charging is carried out in the valley electricity price time period, and discharging is carried out in the peak electricity price time period, so that the electric charge expenditure of the data center is saved. Through real-time monitoring of the UPS systems, the discharge proportions of the storage battery packs corresponding to different UPS systems are dynamically adjusted; according to the energy storage control system provided by the embodiment of the invention, one UPS system supplies power to a plurality of UPS systems, so that the redundant capacity of the storage battery pack is utilized to the maximum extent while emergency standby power of the data center is guaranteed, and earnings are created.

Description

Technical Field

[0001] The present application relates to the technical field of energy storage control, and in particular to a method and system for energy storage control. Background Art

[0002] With the widespread application of data centers, the rapid expansion of the Internet and big data, the importance of data centers has been continuously improved. As a basic power supply device, the reliability of the uninterruptible power supply (UPS) system plays a very critical role in the safe operation of the data center. Therefore, the UPS and its supporting battery pack also need to match the scale of the data center to ensure that reliable and uninterrupted power can be provided for the continuous operation of the data center. In particular, it is often necessary to determine the scale of the uninterruptible power supply and its supporting battery pack according to the full load design of the entire data center at the beginning of the construction of the data center, and it is necessary to install the uninterruptible power supply and the battery pack in place at the beginning of the construction of the data center. However, although the UPS and battery pack configured in this way contain objective power capacity, in the early or even mid-term stage of the construction of the data center, the power-consuming equipment has not been fully installed or put into use, so a large power redundancy of the battery pack is generated. In addition, even after all the power-consuming equipment is put into use, according to the design plan, the battery pack only needs to discharge and operate when the city power fails or the power is interrupted, and most of the other time is idle and redundant. Therefore, a storage control system and method that can efficiently utilize the battery pack of the data center is needed. Summary of the invention

[0003] The embodiments of the present application provide a method and system for energy storage control to solve the defect in the prior art that the electric energy stored in the battery as the power supply unit in the data center cannot be fully utilized.

[0004] To achieve the above-mentioned purpose, the embodiment of the present application provides an energy storage control system for a data center, including: an EMS controller, multiple UPS systems, multiple ATS switches, multiple U-electric contactors, multiple mains contactors, multiple UPS output contactors, a U-electric bus and a mains bus,

[0005] The multiple UPS systems are connected to independent battery packs, and each UPS system is connected to the U power bus at the output end through the UPS output contactor;

[0006] The U electric bus and the mains bus are connected to the backup input and the main input of each ATS switch in the plurality of ATS switches through the U electric contactor and the mains contactor respectively;

[0007] The U power contactor, the mains contactor and the UPS output contactor are connected to the EMS controller via a communication line;

[0008] Each UPS system in the plurality of UPS systems is connected to the EMS controller via the communication line.

[0009] The embodiment of the present application further provides an energy storage control method for a data center, the energy storage control method is applied to an energy storage control system according to the embodiment of the present application, and includes:

[0010] Analyze the load conditions of each UPS system and the capacity of the corresponding battery pack;

[0011] Based on the analysis results and in combination with the overall backup time requirement of the energy storage control system, the allowable discharge ratio of the battery group of each UPS system is calculated and set;

[0012] According to the time period of peak, valley and flat electricity prices, the corresponding charging or discharging procedures are executed.

[0013] According to a method and system for energy storage control in an embodiment of the present application, multiple UPS systems in a data center are connected to form an integrated system through an EMS controller, a UPS output contactor, a U-power input contactor, a mains contactor, and an ATS switch, so that the allowable discharge ratio of the battery group of each UPS system can be calculated and set based on the analysis of the load conditions of each UPS system and the capacity of the corresponding battery group, and combined with the overall backup time requirement of the energy storage control system, so as to execute the corresponding charging or discharging program according to the time period of peak, valley, and flat electricity prices. Therefore, according to the energy storage control system and method in an embodiment of the present application, a UPS system can be selected as a discharging UPS system according to the actual load, and the remaining capacity can be used for peak-valley arbitrage and to extend the backup time of other UPS with higher load rates, thereby providing sufficient backup time guarantee. At the same time, charging can be performed in the valley electricity price time period according to time, and discharging can be performed in the peak electricity price time period, so as to avoid overloading the discharging UPS system when charging multiple UPS systems.

[0014] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0016] Figure 1 is a schematic structural diagram showing an embodiment of an energy storage control system provided by the present application;

[0017] Figure 2 is a connection diagram showing an EMS controller in an energy storage control system provided by the present application;

[0018] Figure 3 A flow chart of an embodiment of the energy storage control method provided in the present application. DETAILED DESCRIPTION

[0019] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0020] The solution provided in the embodiments of the present application can be applied to any energy storage control device or equipment that has charging and discharging capabilities.

[0021] With the widespread application of data centers and the rapid development of science and technology, the rapid expansion of the Internet and big data has made data centers increasingly important. In this context, the reliability of the uninterruptible power supply (UPS) system as a basic power supply system is crucial to the safe operation of the data center. Therefore, the UPS and its supporting power supply unit group need to match the scale of the data center to ensure that the data center can obtain a reliable and uninterrupted energy supply. Usually, in the early stage of data center construction, it is necessary to determine the scale of the UPS and its power supply unit group according to the full load design of the entire data center, and install them in place at one time. However, although this configuration method provides sufficient power capacity, in the early and even mid-term stages of data center construction, since all power-consuming equipment has not been installed or put into use, it often leads to a large power redundancy in the power supply unit group. In addition, even after all power-consuming equipment is put into use, according to the design plan, the battery pack is only discharged when the mains fails or the power is interrupted, and it is mostly idle at other times.

[0022] In the prior art, although a scheme for discharging each unit in the power supply unit group has been proposed, in such a scheme, the discharge ratio of the power supply unit group is artificially set and cannot be adjusted in time according to load changes. This makes it easy to cause insufficient backup power when the redundant power in the power supply unit is used for energy storage adjustment in the prior art. Secondly, when a data center is equipped with multiple UPS, since each UPS usually corresponds to different power-consuming equipment, its load conditions are different, and the usage of stored power is also different, the energy storage conditions of different UPS in the prior art are uneven. The existing scheme only relies on charging during low electricity prices. Since the charging speed of all power supply units is the same, power supply units with larger power consumption require longer time to charge. If the charging time is limited, it may cause the power supply units with larger power consumption to be not fully charged, and have to be charged during non-low electricity prices, which increases energy consumption costs.

[0023] In this regard, the present application proposes an energy storage control system and method. Figure 1 As shown in , the energy storage control system according to the embodiment of the present application may include: multiple UPS (uninterruptible power supply system) systems 12, multiple ATS (automatic transfer switch) switches 13, multiple U-electric contactors 14, multiple AC contactors 15, multiple UPS output contactors 16, U-electric bus 17 and AC bus 18.

[0024] In an embodiment of the present application, each of the multiple UPS systems 12 used in a data center may have an input switch 122, a maintenance bypass switch 123, a rectifier 124, a battery pack 125, an inverter 126, an STS (static transfer switch) switch 127, and an output switch 128.

[0025] One end of the input switch 122 may be connected to the ATS switch 13 corresponding to the UPS system 12 and the other end may be connected to one end of the rectifier 124 and one end of the maintenance bypass switch 123, respectively. The other end of the rectifier 124 may be connected to the battery bank 125 together with one end of the inverter 126. The other end of the inverter 126 may be connected to one end of the STS switch 127, and the one end of the STS switch 127 may be connected to the other end of the input switch 122 connected to the rectifier 124. The other end of the STS switch 127 may be connected to one end of the output switch 128. The other end of the output switch 128 and the other end of the maintenance bypass switch 123 may be connected to the UPS output contactor 16 together.

[0026] Each UPS system 12 can be connected to the U power bus 17 at the output end through the UPS output contactor 16. The U power bus 17 and the main power bus 18 are connected to the backup input and the main input of each ATS switch in the plurality of ATS switches 13 through the U power contactor 14 and the main power contactor 15, respectively. Figure 2As shown in , the U electric contactor 14, the mains contactor 15 and the UPS output contactor 16 are connected to the EMS controller 11 through a communication line, so that data can be exchanged with the EMS controller 11 through the communication line, and control instructions of the EMS controller 11 can be received to charge and discharge the battery pack. The EMS controller 11 can have a built-in processor and memory, and the energy storage control method according to the embodiment of the present application can be stored in the memory in the form of a program, so as to realize the control of the U electric contactor 14, the mains contactor 15, the UPS output contactor 16 and the UPS system.

[0027] For example, Figure 3 As shown in , the energy storage control method according to the embodiment of the present application may include:

[0028] S301, analyzing the load conditions of each UPS system and the capacity of the corresponding battery pack.

[0029] In step S301, the EMS controller 11 can obtain the load conditions of each UPS system and the capacity of its battery pack through the communication line. For example, assuming that the energy storage system of the current data center includes n UPS systems U1-Un, then in step S301, the current power load power P (in kW) and the capacity C (in Wh) of its battery pack and SOC (battery state of charge) data of each UPS system Ui can be obtained.

[0030] S302, based on the analysis results and in combination with the overall backup time requirement of the energy storage control system, calculate and set the allowable discharge ratio of the battery group of each UPS system.

[0031] In step S302, based on the analysis results of the load conditions and the capacity of the battery pack of each UPS system acquired in step S301, and combined with the backup time T (in hours h) of the entire energy storage control system, the allowable charge and discharge ratio of the battery pack of each UPS system Ui can be calculated and set. For example, the formula Pc = C × SOC ÷ 1000 can be used to calculate the available capacity Pc of each battery pack. Then, according to the backup time T preset for each UPS system, the formula Pb = P × T is used to calculate the currently required backup power Pb, and for the calculated currently required backup power Pb, the redundancy coefficient k (k>1) of the backup power can be further applied. The redundancy coefficient k indicates that a certain amount of redundancy is provided on the basis of the backup power Pb.

[0032] S303, executing corresponding charging or discharging procedures according to the time period of peak, valley and flat electricity prices.

[0033] In step S303, corresponding charge and discharge procedures can be executed according to the time period in which the current time is located. For example, in the embodiments of the present application, the charge and discharge procedures may include: a mode determination process; a charge and discharge control process, and a linkage discharge process.

[0034] For example, the mode determination process may be used to determine which mode state each UPS should be in currently. In the embodiments of the present application, the UPS can be set to be in three mode states: a charging mode, a discharging mode, and a standby power mode. In the charging mode, the UPS system can charge the battery pack; in the discharging mode, the UPS system can discharge the battery pack, that is, use the electric energy stored in the battery pack to supply power to other devices or other battery packs; in the standby power mode, the UPS system neither charges nor discharges the battery pack. Regardless of which mode the UPS is in, when a mains power failure occurs, the UPS automatically discharges and supplies power using the battery pack. Therefore, in the embodiments of the present application, the mode determination process may include:

[0035] Obtain the mains power information of the data center and determine whether there is a mains power failure;

[0036] When it is determined that there is a mains power failure, the UPS system supplies power using the battery pack based on a preset logic;

[0037] When it is determined that there is no mains power failure, perform the following processing:

[0038] Obtain the current power consumption load power P of multiple sets of UPS systems, the capacity C of the battery pack, and the SOC data; use the formula Pc = C × SOC ÷ 1000 to calculate the available capacity Pc of the battery pack;

[0039] According to the preset backup time T, use the formula Pb = P × T to calculate the current required backup power Pb;

[0040] For the calculated current required backup power Pb, further apply a redundancy factor k for the backup power, where the redundancy factor k represents providing a certain redundancy on the basis of the backup power Pb, and k > 1;

[0041] Determine the mode of the UPS system according to the available capacity Pc of the battery pack and the backup power Pb: When Pc > Pb

[0042] × k, that is, the remaining power of the battery pack is relatively sufficient and can be discharged, so it is determined that the UPS system is in the discharging mode; when Pc < Pb, that is, the remaining power of the battery pack is insufficient and needs to be charged, so it is determined that the UPS system is in the charging mode; when Pb ≤ PC ≤ Pb × k, it is determined that the UPS system is in the standby power mode.

[0043] In the embodiment of the present application, the charge and discharge control process may include:

[0044] When it is determined that the UPS system 12 is in the charging mode, controlling the UPS system 12 to charge its battery pack;

[0045] Determine whether the current time belongs to the off-peak electricity price period, the normal electricity price period, or the peak electricity price period;

[0046] When it is determined that the current time is in the off-peak electricity price period, determining whether the SOC of the UPS system 12 is less than 100%, and when it is determined that the SOC is less than 100%, controlling the UPS system 12 to charge its battery pack;

[0047] When it is determined that the current time is in the peak electricity price period, it is determined whether the UPS system 12 is in the discharge mode, and when it is determined that the UPS system 12 is in the discharge mode, the UPS system 12 is controlled to discharge its storage battery group.

[0048] In addition, in the embodiment of the present application, when the current time is in the peak electricity price period or when the current system is in a mains failure, the linkage discharge process can be executed. For example, when it is determined that there is a mains failure, the linkage discharge process may include:

[0049] Sorting all UPS systems 12 in descending order according to their current SOC values, and obtaining a UPS system queue Ua-Un, wherein Ua represents a UPS system UPSa with the highest SOC value, Un represents a UPS system UPSn with the lowest SOC value, and SOCa represents the SOC of the UPS system Ua, and SOCn represents the SOC of the UPS system Un;

[0050] It is determined whether SOCa÷k>SOCn holds, and when it is determined to hold, a matrix discharge process is performed on the UPS system Ua.

[0051] When it is determined that there is no mains fault at present, the linkage discharge process may include:

[0052] Determine whether the current time is in the peak electricity price period;

[0053] When it is determined that the current time is in the peak electricity price period, all UPS systems 12 are sorted in descending order according to their current SOC values, and a UPS system queue Ua-Un is obtained, where Ua represents the UPS system UPSa with the highest SOC value, Un represents the UPS system UPSn with the lowest SOC value, and SOCa represents the SOC of the UPS system Ua, and SOCn represents the SOC of the UPS system Un;

[0054] Determine whether SOCa÷k > SOCn holds, and when it is determined to hold, perform a matrix discharge process on the UPS system Ua.

[0055] In the embodiments of the present application, the above matrix discharge process may include:

[0056] According to the remaining available capacity Pc, rated load Pe, and current real-time load Pr of the UPS system, calculate the remaining available load Ps of each UPS system 12 based on the formula Ps = Pe - Pr, and calculate the maximum power consumption load Pt of each UPS system 12 based on the formula Pt = Pr + Pi according to the current real-time load Pr of the UPS system 12 and the maximum charging power Pi of its battery pack;

[0057] For each UPS system Ui in the other UPS systems in the UPS system queue Ua to Un except for the UPS system Ua used for discharging, determine whether its SOC value satisfies SOCi×k < SOCa;

[0058] When it is determined that the SOC value of the UPS system Ui satisfies SOCi×k < SOCa, put the UPS system Ui into the combination Q, and all the UPS systems in the combination Q are arranged in ascending order according to their SOC values to form a queue Q(U1, U2,..., Um);

[0059] For each UPS system Ui in the queue Q, sequentially determine whether its maximum power consumption load Pt is less than the remaining available load Ps of the UPS system Ua used for discharging. When it is determined that its maximum power consumption load Pt is less than the remaining available load Ps of the UPS system Ua used for discharging, put the UPS system Ui into the power receiving device combination T, and subtract the maximum power consumption load Pt of the UPS system Ui put into the power receiving device combination T from the remaining available load Ps of the UPS system Ua used for discharging, and use the value after subtracting the Pt of the Ui as the remaining available load Ps value for the next judgment of the next UPS system until the above determination is performed for all the UPS systems in the queue Q, and a power receiving device combination T is formed, and all the UPS systems in the power receiving device combination T are arranged in ascending order according to their SOC values;

[0060] Send a control signal from the EMS controller 11 to the UPS system Ua to turn on its UPS output contactor 16.

[0061] In addition, in the embodiments of the present application, for each set of UPS systems 12 in the power receiving device combination T, the following steps may be used to form an actual power receiving combination S and a non-powered receiving combination U. The non-powered receiving combination U may include all the other UPS systems in the power receiving device combination T except for the UPS systems included in the actual power receiving combination S:

[0062] For each UPS system Ui in the powered equipment combination T, it is determined in turn whether its maximum power load Pt is less than the remaining available load Ps of the UPS system Ua used for discharge. When it is determined that its maximum power load Pt is less than the remaining available load Ps of the UPS system Ua used for discharge, the EMS controller 11 sends a control signal to the UPS system Ui to turn on its U power contactor 14 and disconnect its AC contactor 15, and move the UPS system Ui from the non-powered combination U to the actual powered combination S;

[0063] Determine whether the current remaining available load Ps of the UPS system Ua for discharging the UPS system Ui is less than zero, and when it is determined that the current remaining available load Ps of the UPS system Ua for discharging is less than zero, the EMS controller 11 sends a control signal to the UPS system Ui to turn on its AC contactor 15 and disconnect its U power contactor 14, and move the UPS system Ui from the actual power receiving combination S to the non-power receiving combination U;

[0064] For each UPS system Ui in the actual power receiving combination S, it is determined whether its SOC value is greater than or equal to the SOC value of the UPS system Ua used for discharging, and when it is determined that its SOC value is greater than or equal to the SOC value of the UPS system Ua used for discharging, the EMS controller 11 sends a control signal to the UPS system Ui to turn on its mains contactor 15 and disconnect its U power contactor 14, and move the UPS system Ui from the actual power receiving combination S to the non-power receiving combination U;

[0065] When the current remaining available load aPs of the UPS system Ua used for discharge satisfies the following formula aPs≤aPb×k, the EMS controller 11 sends a control signal to all UPS systems 12 in the actual power receiving combination S to turn on their AC power contactors 15 and disconnect their U power contactors 14, and then the EMS controller 11 sends a control signal to the UPS system Ua for discharge to disconnect its UPS output contactor 16.

[0066] According to the energy storage control system and method of the data center of the embodiment of the present application, by connecting multiple UPS systems of the data center through EMS controller, UPS output contactor, U power input contactor, mains contactor and ATS switch to form an integrated system, it is possible to calculate and set the allowable discharge ratio of the battery group of each UPS system based on the analysis of the load conditions of each UPS system and the capacity of the corresponding battery group, and in combination with the overall backup time requirement of the energy storage control system, so as to execute the corresponding charging or discharging program according to the time period of the peak, valley and flat electricity price. Therefore, according to the energy storage control system and method of the embodiment of the present application, it is possible to select a UPS system as the UPS system for discharge according to the actual load, and use the remaining capacity for peak-valley arbitrage and extend the backup time of other UPS with higher load rates, thereby providing sufficient backup time guarantee, and at the same time, it is possible to charge in the valley electricity price time period according to the time, and discharge in the peak electricity price time period, and avoid overloading the discharge UPS system when providing charging for multiple UPS systems. In particular, it is possible to utilize the excess capacity of the battery group to maximize the charging in the valley electricity price time period and the discharging in the peak electricity price time period, effectively reducing electricity bill expenditure and forming economic benefits. In use, the allowable discharge ratio of each battery pack can be dynamically calculated according to the actual load, which is more reasonable, reliable and efficient. Through the matrix discharge method, the controller can schedule the remaining capacity of the supporting battery packs of each UPS, and maximize the use of the remaining capacity when the UPS load rate is unbalanced. Through the matrix discharge method of the embodiment of the present application, the backup time of each UPS can be balanced in the event of a mains failure.

[0067] Those skilled in the art can understand that all or part of the steps of implementing the above-mentioned method embodiments can be completed by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When the program is executed, the steps of the above-mentioned method embodiments are executed; and the aforementioned storage medium includes: ROM, RAM, disk or optical disk and other media that can store program codes.

[0068] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An energy storage control system, characterized in that: include: EMS controller, multiple UPS systems, multiple ATS switches, multiple U-electric contactors, multiple mains contactors, multiple UPS output contactors, U-electric buses and mains buses, The multiple UPS systems are connected to independent battery packs, and each UPS system is connected to the U power bus at the output end through the UPS output contactor; The U electric bus and the mains bus are connected to the backup input and the main input of each ATS switch in the plurality of ATS switches through the U electric contactor and the mains contactor respectively; The U power contactor, the mains contactor and the UPS output contactor are connected to the EMS controller via a communication line; Each UPS system in the plurality of UPS systems is connected to the EMS controller via the communication line.

2. The energy storage control system according to claim 1, characterized in that: The EMS controller has a built-in processor and a memory, and the memory stores a program for controlling the U power contactor, the mains contactor, the UPS output contactor and the UPS system.

3. The energy storage control system according to claim 2, characterized in that: The UPS system includes: an input switch, a maintenance bypass switch, a rectifier, a battery pack, an inverter, an STS switch and an output switch, and One end of the input switch is connected to the ATS switch corresponding to the UPS system and the other end is respectively connected to the rectifier and one end of the maintenance bypass switch; The other end of the rectifier and one end of the inverter are commonly connected to the battery pack; The other end of the inverter is connected to one end of the STS switch, and the one end of the STS switch is connected to the other end of the input switch connected to the rectifier; The other end of the STS switch is connected to one end of the output switch; The other end of the output switch and the other end of the maintenance bypass switch are commonly connected to the UPS output contactor.

4. A method for controlling energy storage, characterized in that: The energy storage control method is applied to the energy storage control system according to any one of claims 1 to 3, and comprises: Analyze the load conditions of each UPS system and the capacity of the corresponding battery pack; Based on the analysis results and in combination with the overall backup time requirement of the energy storage control system, the allowable discharge ratio of the battery group of each UPS system is calculated and set; According to the time period of peak, valley and flat electricity prices, the corresponding charging or discharging procedures are executed.

5. The energy storage control method according to claim 4, characterized in that: The execution of the corresponding charging or discharging procedures according to the time period of the peak, valley and flat electricity prices includes: a mode judgment process; a charging and discharging control process and a linkage discharge process.

6. The energy storage control method according to claim 5, characterized in that: The mode determination process includes: Obtain the data center's mains power information and determine whether there is a mains power failure; When it is determined that there is a mains power failure, the UPS system uses the battery pack to supply power based on a preset logic; When it is determined that there is no mains failure, the following processing is performed: Obtaining current power load power P of the multiple UPS systems and capacity C and SOC data of the battery packs; Use the formula Pc = C × SOC ÷ 1000 to calculate the available capacity Pc of the battery pack; According to the preset backup time T, use the formula Pb = P × T to calculate the currently required backup power Pb; For the calculated current required backup power Pb, the redundancy factor k of the backup power is further applied, where the redundancy factor k represents providing a certain redundancy on the basis of the backup power Pb, and k > 1; Based on the available capacity Pc and the backup power Pb of the battery pack, determine the mode of the UPS system: when Pc > Pb × k, determine that the UPS system is in the discharge mode; when Pc < Pb, determine that the UPS system is in the charging mode; when Pb ≤ PC ≤ Pb × k, determine that the UPS system is in the standby power mode.

7. The energy storage control method according to claim 6, characterized in that: The charge and discharge control process includes: When it is determined that the UPS system is in the charging mode, control the UPS system to charge its battery pack; Determine whether the current time belongs to the valley-time electricity price period, the normal-time electricity price period, or the peak-time electricity price period; When it is determined that the current time is in the valley-time electricity price period, determine whether the SOC of the UPS system is less than 100%, and when it is determined that the SOC is less than 100%, control the UPS system to charge its battery pack; When it is determined that the current time is in the peak-time electricity price period, determine whether the UPS system is in the discharge mode, and when it is determined that the UPS system is in the discharge mode, control the UPS system to discharge its battery pack.

8. The energy storage control method according to claim 7, characterized in that: The linked discharge process includes: When it is determined that there is a mains power failure currently, sort all UPS systems in descending order according to their current SOC values, and obtain the UPS system queue Ua~Un, where Ua represents the UPS system UPSa with the highest SOC value, Un represents the UPS system UPSn with the lowest SOC value, and SOCa represents the SOC of the UPS system Ua, and SOCn represents the SOC of the UPS system Un; Determine whether SOCa ÷ k > SOCn holds, and when it is determined to hold, perform the matrix discharge process on the UPS system Ua.

9. The energy storage control method according to claim 7, characterized in that: The linked discharge process includes: When it is determined that there is no mains power failure currently, determine whether the current time is in the peak-time electricity price period; When it is determined that the current time is in the peak-time electricity price period, sort all UPS systems in descending order according to their current SOC values, and obtain the UPS system queue Ua~Un, where Ua represents the UPS system UPSa with the highest SOC value, Un represents the UPS system UPSn with the lowest SOC value, and SOCa represents the SOC of the UPS system Ua, and SOCn represents the SOC of the UPS system Un; Determine whether SOCa ÷ k > SOCn holds, and when it is determined to hold, perform the matrix discharge process on the UPS system Ua.

10. The energy storage control method according to claim 8 or 9, characterized in that: The matrix discharge process includes: Based on the remaining available capacity Pc, the rated load Pe, and the current real-time load Pr of the UPS system, calculate the remaining available load Ps of each UPS system based on the formula Ps = Pe - Pr, and based on the current real-time load Pr of the UPS system and the maximum charging power Pi of its battery pack, calculate the maximum power consumption load Pt of each UPS system based on the formula Pt = Pr + Pi; For each UPS system Ui in the other UPS systems in the UPS system queues Ua to Un except the UPS system Ua used for discharging, determine whether its SOC value satisfies SOCi × k < SOCa; When it is determined that the SOC value of the UPS system Ui satisfies SOCi × k < SOCa, put the UPS system Ui into the combination Q, and all the UPS systems in the combination Q are arranged in ascending order of their SOC values to form the queue Q(U1, U2,..., Um); For each UPS system Ui in the queue Q, sequentially determine whether its maximum power consumption load Pt is less than the remaining available load Ps of the UPS system Ua used for discharging. When it is determined that its maximum power consumption load Pt is less than the remaining available load Ps of the UPS system Ua used for discharging, put the UPS system Ui into the power receiving device combination T, and subtract the maximum power consumption load Pt of the UPS system Ui put into the power receiving device combination T from the remaining available load Ps of the UPS system Ua used for discharging, and use the value after subtracting the Pt of the Ui as the remaining available load Ps value for the next judgment of the next UPS system until the above determination is performed for all the UPS systems in the queue Q, and form the power receiving device combination T. All the UPS systems in the power receiving device combination T are arranged in ascending order of their SOC values; Send a control signal from the EMS controller to the UPS system Ua to turn on its UPS output contactor; For each set of UPS systems in the power receiving device combination T, form the actual power receiving combination S and the non-powered receiving combination U using the following steps, where the non-powered receiving combination U contains all the other UPS systems in the power receiving device combination T except the UPS systems included in the actual power receiving combination S: For each UPS system Ui in the power receiving device combination T, sequentially determine whether its maximum power consumption load Pt is less than the remaining available load Ps of the UPS system Ua used for discharging. When it is determined that its maximum power consumption load Pt is less than the remaining available load Ps of the UPS system Ua used for discharging, the EMS controller sends a control signal to the UPS system Ui to turn on its U power contactor and turn off its mains contactor, and move the UPS system Ui from the non-powered receiving combination U to the actual power receiving combination S; Determine whether the current remaining available load Ps of the UPS system Ua discharging the UPS system Ui is less than zero, and when it is determined that the current remaining available load Ps of the UPS system Ua used for discharging is less than zero, the EMS controller sends a control signal to the UPS system Ui to turn on its mains contactor and turn off its U power contactor, and move the UPS system Ui from the actual power receiving combination S to the non-powered receiving combination U; For each UPS system Ui in the actual power receiving combination S, it is determined whether its SOC value is greater than or equal to the SOC value of the UPS system Ua used for discharging, and when it is determined that its SOC value is greater than or equal to the SOC value of the UPS system Ua used for discharging, the EMS controller sends a control signal to the UPS system Ui to turn on its mains contactor and disconnect its U power contactor, and move the UPS system Ui from the actual power receiving combination S to the non-power receiving combination U; When the current remaining available load aPs of the UPS system Ua used for discharge satisfies the following formula aPs≤aPb*k, the EMS controller sends a control signal to all UPS systems in the actual power receiving combination S to turn on their AC power contactors and disconnect their U power contactors, and then the EMS controller sends a control signal to the UPS system Ua for discharge to disconnect its UPS output contactor.

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