Energy storage discharge management method and system

Abstract

The invention provides an energy storage discharge management method and system, and the method comprises the steps: obtaining a transformer power threshold PD, and obtaining the discharge power P of an energy storage system; when the energy storage system discharges, the cloud server obtains the real-time power PS of the transformer; when the cloud server determines that PS is less than or equal to PD, the cloud server instructs the energy storage system to reduce the discharge power P, and at the moment, the real-time power PS of the transformer is gradually increased until PS is greater than PD; and when the cloud server determines that PS is less than 0, the cloud server determines that the energy storage system transmits power to the power grid, instructs the energy storage system to be shut down, and issues a countercurrent alarm. Therefore, when the energy storage system discharges, the current of the user distribution transformer can be monitored in real time, and the discharge power of the energy storage project is controlled so as to prevent the energy storage project from reversely transmitting power to the high-voltage side of the distribution transformer.

Description

Technical Field

[0001] The present invention relates to the technical field of energy storage management, and in particular to an energy storage discharge management method and system. Background Art

[0002] Energy management system (EMS) is a system used to monitor, control and optimize energy use. It helps enterprises effectively manage energy consumption, improve energy efficiency and reduce energy costs by collecting and analyzing energy data in real time.

[0003] The current EMS controls the operation mode of the energy storage system to monitor the power direction at the mains grid connection, the operating status of the energy storage system, and the load power. The energy storage equipment currently used is affected by the manufacturing process. As the charging and discharging cycles increase, it is difficult to ensure the consistency of the energy storage equipment. During charging and discharging, disordered charging and discharging will affect the energy storage effect. At the same time, it is difficult to ensure the normal operation of the microgrid and the life of the energy storage equipment.

[0004] The current energy storage system is used as a backup power source for part of the load after the city power fails. If there is no on-site staff to debug it, it is easy to have the problem of backflow of electricity to the grid. Summary of the invention

[0005] The present application provides an energy storage discharge management method and system, which can monitor the current of the user's distribution transformer in real time when the energy storage system is discharging, and control the discharge power of the energy storage project to prevent the energy storage project from back-feeding electricity to the high-voltage side of the distribution transformer.

[0006] In view of this, the present application provides a method for managing energy storage discharge, the method comprising: obtaining a transformer power threshold PD, obtaining a discharge power P of an energy storage system; when the energy storage system is discharging, a cloud server obtains the transformer real-time power PS; when the cloud server determines that PS≤PD, the cloud server instructs the energy storage system to reduce the discharge power P, at which time the transformer real-time power PS gradually increases until PS>PD; when the cloud server determines that PS<0, the cloud server determines that the energy storage system transmits power to the power grid, instructs the energy storage system to shut down, and issues a reverse current alarm.

[0007] Optionally, in combination with the first aspect, in a possible implementation, the cloud server instructs the energy storage system to reduce the discharge power P specifically including: the cloud server sends a discharge power reduction instruction to the local EMS system through the MQTT protocol, which is forwarded by the local EMS system to the energy storage system, so as to enable the energy storage system to reduce the discharge power P; the instructing the energy storage system to shut down specifically includes: the cloud server sends a shutdown instruction to the local EMS system through the MQTT protocol, which is forwarded by the local EMS system to the energy storage system, so as to enable the energy storage system to shut down.

[0008] Optionally, in combination with the first aspect, in a possible implementation, the method further includes: when the cloud server determines that PS>PD, the cloud server instructs the energy storage system to increase the discharge power P, and the transformer real-time power PS gradually decreases until PS≤PD.

[0009] Optionally, in combination with the first aspect, in a possible implementation, the cloud server instructs the energy storage system to increase the discharge power P specifically including: the cloud server sends an increase power instruction to the local EMS system through the MQTT protocol, and the local EMS system forwards it to the energy storage system, so as to enable the energy storage system to increase the discharge power P.

[0010] Optionally, in combination with the first aspect, in a possible implementation, the method further includes: ending the discharge when the remaining battery capacity SOC reaches a preset low value or the discharge time period ends.

[0011] The second aspect of the present application provides an energy storage discharge management system, characterized in that the device includes: a cloud server, an energy storage system, the cloud server is used to obtain a transformer power threshold PD; when the energy storage system is discharging, the cloud server is used to obtain the transformer real-time power PS; when it is determined that PS≤PD, the cloud server is used to instruct the energy storage system to reduce the discharge power P, at which time the transformer real-time power PS gradually increases until PS>PD; when it is determined that PS<0, the cloud server determines that the energy storage system transmits power to the power grid, is used to instruct the energy storage system to shut down, and issue a reverse current alarm.

[0012] Optionally, in combination with the second aspect, in a possible implementation, the system also includes an on-site EMS system, and the cloud server is specifically used to: send a discharge power reduction instruction to the on-site EMS system through the MQTT protocol, which is forwarded by the on-site EMS system to the energy storage system, so as to reduce the discharge power P of the energy storage system; send a shutdown instruction to the on-site EMS system through the MQTT protocol, which is forwarded by the on-site EMS system to the energy storage system, so as to shut down the energy storage system.

[0013] Optionally, in combination with the second aspect, in a possible implementation, the cloud server is further used to: when it is determined that PS>PD, instruct the energy storage system to increase the discharge power P, at which time the transformer real-time power PS gradually decreases until PS≤PD.

[0014] Optionally, in combination with the second aspect, in a possible implementation, the cloud server is specifically used to: send a power increase instruction to the local EMS system through the MQTT protocol, and the local EMS system forwards it to the energy storage system to enable the energy storage system to increase the discharge power P.

[0015] Optionally, in combination with the second aspect, in a possible implementation, the energy storage system is further used to: end the discharge when it is determined that the remaining battery power SOC reaches a preset low value, or when the discharge time period ends.

[0016] The present application provides a method and system for energy storage discharge management, which includes obtaining a transformer power threshold PD, obtaining the discharge power P of the energy storage system; when the energy storage system is discharging, the cloud server obtains the real-time power PS of the transformer; when the cloud server determines that PS≤PD, the cloud server instructs the energy storage system to reduce the discharge power P, at which time the real-time power PS of the transformer gradually increases until PS>PD; when the cloud server determines that PS<0, the cloud server determines that the energy storage system transmits power to the power grid, instructs the energy storage system to shut down, and issues a reverse flow alarm. In this way, when the energy storage system is discharging, the current of the user's distribution transformer can be monitored in real time, and the discharge power of the energy storage project can be controlled to prevent the energy storage project from sending power back to the high-voltage side of the distribution transformer. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic diagram of a flow chart of an energy storage discharge management method provided in an embodiment of the present application; Figure 2 A schematic diagram of a flow chart of an energy storage discharge management system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of this application.

[0019] The term "and / or" in this application can be a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this application generally indicates that the associated objects before and after are in an "or" relationship.

[0020] The terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or modules is not necessarily limited to those steps or modules that are clearly listed, but may include other steps or modules that are not clearly listed or inherent to these processes, methods, products or devices.

[0021] The current EMS controls the operation mode of the energy storage system to monitor the power direction at the mains grid connection, the operating status of the energy storage system, and the load power. The energy storage equipment currently used is affected by the manufacturing process. As the charging and discharging cycles increase, it is difficult to ensure the consistency of the energy storage equipment. During charging and discharging, disordered charging and discharging will affect the energy storage effect. At the same time, it is difficult to ensure the normal operation of the microgrid and the life of the energy storage equipment.

[0022] The current energy storage system is used as a backup power source for part of the load after the city power fails. If there is no on-site staff to debug it, it is easy to have the problem of backflow of electricity to the grid.

[0023] Therefore, this application provides a method for managing energy storage discharge, see Figure 1 , the method comprising: S11. Obtain the transformer power threshold PD, and obtain the discharge power P of the energy storage system.

[0024] The cloud server obtains the transformer power threshold PD, which is generally a fixed value, and obtains the discharge power P of the energy storage system.

[0025] S12. When the energy storage system is discharging, the cloud server obtains the real-time power PS of the transformer.

[0026] When the energy storage system is discharging, the cloud server obtains the real-time power PS of the transformer.

[0027] S13. When the cloud server determines that PS≤PD, the cloud server instructs the energy storage system to reduce the discharge power P. At this time, the real-time power PS of the transformer gradually increases until PS>PD.

[0028] When the cloud server determines that PS≤PD, the cloud server instructs the energy storage system to reduce the power P. At this time, the real-time power PS of the transformer gradually increases until PS>PD.

[0029] Furthermore, the cloud server sends a discharge power reduction instruction to the local EMS system through the message queuing telemetry transport (MQTT) protocol, and the local EMS system forwards it to the energy storage system to enable the energy storage system to reduce the discharge power P.

[0030] S14. When the cloud server determines that PS is less than 0, the cloud server determines that the energy storage system transmits power to the power grid, instructs the energy storage system to shut down, and issues a reverse flow alarm.

[0031] When the cloud server determines that PS<0, the cloud server instructs the energy storage system to shut down and issues a reverse flow alarm.

[0032] Furthermore, the cloud server sends a shutdown command to the local EMS system via the MQTT protocol, which is forwarded to the energy storage system by the local EMS system to shut down the energy storage system. At the same time, the cloud server sends a reverse flow alarm to the local EMS system via the MQTT protocol, which is forwarded to the energy storage system by the local EMS system.

[0033] It should be noted that during discharge, the rated power of the energy storage system cannot completely cover the power on the load side. During discharge, the energy storage system and the grid discharge at the same time. The more the energy storage system discharges, the less power the grid discharges. Conversely, if the energy storage system discharges less, the more power the grid discharges. PS detects the power of the transformer, and the power of the grid comes directly from the transformer. The real-time power of the transformer is equivalent to the real-time power provided by the grid. Therefore, if the discharge power P of the energy storage system is reduced, the real-time power PS of the transformer will gradually increase. When the energy storage system discharges more, the grid discharge will decrease. When the power cannot be controlled near the PD, a shutdown command is directly issued. The essence of load tracking is to control the PS near the PD. If it cannot be controlled, the reverse flow alarm and shutdown processing in the anti-reverse flow strategy are executed. In this way, when the energy storage system is discharged, the current of the user's distribution transformer can be monitored in real time, the discharge power of the energy storage project can be controlled, and the energy storage project can be prevented from sending power back to the high-voltage side of the distribution transformer.

[0034] It should be noted that when the energy storage system is discharging, the energy storage discharge management method provided in the present application can achieve second-level regulation so that the discharge power of the energy storage system is close to the power of the transformer load.

[0035] Specifically, the energy storage discharge management method also includes: when the cloud server determines that PS>PD, the cloud server instructs the energy storage system to increase the discharge power P, and the transformer real-time power PS gradually decreases until PS≤PD.

[0036] Furthermore, the cloud server instructs the energy storage system to increase the power P specifically includes: the cloud server sends a power increase instruction to the local EMS system through the MQTT protocol, and the local EMS system forwards it to the energy storage system, so that the energy storage system increases the discharge power P. In this way, the discharge power of the energy storage system is close to the power of the transformer load.

[0037] It is worth noting that the method further includes: when the remaining battery power (state of charge, SOC) reaches a preset low value, or when the discharge time period ends, the discharge is terminated.

[0038] The present application provides a method for managing energy storage discharge, which includes obtaining a transformer power threshold PD, obtaining the discharge power P of the energy storage system; when the energy storage system is discharging, the cloud server obtains the real-time power PS of the transformer; when the cloud server determines that PS≤PD, the cloud server instructs the energy storage system to reduce the discharge power P, at which time the real-time power PS of the transformer gradually increases until PS>PD; when the cloud server determines that PS<0, the cloud server determines that the energy storage system transmits power to the power grid, instructs the energy storage system to shut down, and issues a reverse flow alarm. In this way, when the energy storage system is discharging, the current of the user's distribution transformer can be monitored in real time, and the discharge power of the energy storage project can be controlled to prevent the energy storage project from sending power back to the high-voltage side of the distribution transformer.

[0039] Based on the energy storage discharge management method described above, the present application also provides an energy storage discharge management system, which is used to implement the energy storage discharge management method described above. Figure 2 ,The system includes: cloud server, energy storage system and EMS.

[0040] Among them, the cloud server is used to obtain the transformer power threshold PD, which is used to obtain the discharge power P of the energy storage system; when the energy storage system is discharging, the cloud server is used to obtain the transformer real-time power PS; when it is determined that PS≤PD, the cloud server is used to instruct the energy storage system to reduce the discharge power P, at which time the transformer real-time power PS gradually increases until PS>PD; when it is determined that PS<0, the cloud server determines that the energy storage system transmits power to the power grid, which is used to instruct the energy storage system to shut down and issue a reverse current alarm.

[0041] Specifically, the cloud server is used to: send a discharge power reduction instruction to the local EMS system through the MQTT protocol, which is forwarded by the local EMS system to the energy storage system to reduce the discharge power P of the energy storage system; send a shutdown instruction to the local EMS system through the MQTT protocol, which is forwarded by the local EMS system to the energy storage system to shut down the energy storage system.

[0042] The cloud server is also used to: when it is determined that PS>PD, instruct the energy storage system to increase the discharge power P, at which time the transformer real-time power PS gradually decreases until PS≤PD.

[0043] Specifically, the cloud server is used to send a power increase instruction to the local EMS system through the MQTT protocol, and the local EMS system forwards it to the energy storage system to increase the discharge power P of the energy storage system.

[0044] The energy storage system is also used to: terminate the discharge when it is determined that the remaining battery capacity SOC reaches a preset low value or the discharge time period ends.

[0045] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0046] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions to enable a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, etc., various media that can store program codes.

[0047] In the embodiments provided in this application, it should be understood that the disclosed methods can be implemented in other ways without exceeding the spirit and scope of this application. The current embodiment is only an illustrative example and should not be used as a limitation. The specific content given should not limit the purpose of this application. For example, some features can be ignored or not executed.

[0048] The technical means disclosed in the present application are not limited to the technical means disclosed in the above-mentioned implementation methods, but also include technical solutions composed of any combination of the above technical features. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of this application, and these improvements and modifications are also regarded as the protection scope of this application.

[0049] The above is a detailed introduction to a method and system for energy storage discharge management provided by the embodiments of the present application. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and its core idea of ​​the present application; at the same time, for those of ordinary skill in the art, according to the idea of ​​the present application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application. Although the present application has been described in detail with reference to the aforementioned embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein; and these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for managing energy storage discharge, characterized in that: The method comprises: Obtain the transformer power threshold PD and obtain the discharge power P of the energy storage system; When the energy storage system is discharging, the cloud server obtains the real-time power PS of the transformer; When the cloud server determines that PS≤PD, the cloud server instructs the energy storage system to reduce the discharge power P, and the transformer real-time power PS gradually increases until PS>PD; When the cloud server determines that PS is less than 0, the cloud server determines that the energy storage system transmits power to the power grid, instructs the energy storage system to shut down, and issues a reverse flow alarm.

2. The energy storage discharge management method according to claim 1, characterized in that: The cloud server instructing the energy storage system to reduce the discharge power P specifically includes: The cloud server sends a discharge power reduction instruction to the local EMS system through the MQTT protocol, and the local EMS system forwards it to the energy storage system to enable the energy storage system to reduce the discharge power P; The instructing the energy storage system to shut down specifically includes: The cloud server sends a shutdown command to the local EMS system through the MQTT protocol, and the local EMS system forwards the command to the energy storage system to shut down the energy storage system.

3. The energy storage discharge management method according to claim 1, characterized in that: The method further comprises: When the cloud server determines that PS>PD, the cloud server instructs the energy storage system to increase the discharge power P, and the transformer real-time power PS gradually decreases until PS≤PD.

4. The energy storage discharge management method according to claim 3, characterized in that: The cloud server instructing the energy storage system to increase the discharge power P specifically includes: The cloud server sends a power increase instruction to the local EMS system through the MQTT protocol, and the local EMS system forwards it to the energy storage system to enable the energy storage system to increase the discharge power P.

5. The energy storage discharge management method according to claim 3, characterized in that: The method further comprises: When the battery remaining capacity SOC reaches a preset low value or the discharge time period ends, the discharge ends.

6. An energy storage discharge management system, characterized in that: The device includes: a cloud server, an energy storage system, The cloud server is used to obtain the transformer power threshold PD, which is used to obtain the discharge power P of the energy storage system; When the energy storage system is discharging, the cloud server is used to obtain the real-time power PS of the transformer; When it is determined that PS≤PD, the cloud server is used to instruct the energy storage system to reduce the discharge power P, and the transformer real-time power PS gradually increases until PS>PD; When it is determined that PS<0, the cloud server determines that the energy storage system transmits power to the power grid, instructs the energy storage system to shut down, and issues a reverse flow alarm.

7. The energy storage discharge management system according to claim 6, characterized in that: The system also includes an on-site EMS system, and the cloud server is specifically used for: Sending a discharge power reduction instruction to the local EMS system through the MQTT protocol, which is forwarded by the local EMS system to the energy storage system to reduce the discharge power P of the energy storage system; A shutdown command is sent to the local EMS system via the MQTT protocol, and the local EMS system forwards the command to the energy storage system to shut down the energy storage system.

8. The energy storage discharge management system according to claim 6, characterized in that: The cloud server is also used for: When it is determined that PS>PD, the energy storage system is instructed to increase the discharge power P, and the transformer real-time power PS gradually decreases until PS≤PD.

9. The energy storage discharge management system according to claim 8, characterized in that: The cloud server is specifically used for: The power increase instruction is sent to the local EMS system through the MQTT protocol, and the local EMS system forwards it to the energy storage system to enable the energy storage system to increase the discharge power P.

10. The energy storage discharge management system according to claim 8, characterized in that: The energy storage system is also used for: When it is determined that the battery remaining capacity SOC reaches a preset low value, or the discharge time period ends, the discharge is terminated.

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