Mobile off-network energy storage system and control method

Abstract

The invention discloses a mobile off-grid energy storage system and a control method in the technical field of off-grid energy storage, the system comprises a mobile carrier, and an energy storage unit, a box transformer substation system and load interfaces arranged on the mobile carrier, the energy storage unit comprises a detachable battery system, and the load interfaces comprise an external load interface and an internal load interface; the output end of the battery system is connected to an external load interface and an internal load interface through the box transformer substation system, the external load interface is used for supplying power to an external load, the internal load interface is used for supplying auxiliary power to the battery system and the box transformer substation system, and an auxiliary power supply switch is further arranged between the internal load interface and the battery system; a plurality of energy storage units in the system simultaneously or respectively form an energy storage system with a rear-end box transformer substation system to supply power to a rear-end load, the control method of the system carries out battery system on-load switching according to the residual electric quantity of the battery system put into operation, the function that the off-grid energy storage system continuously supplies power to the load for a long time is achieved, and the use experience is greatly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of off-grid energy storage, and in particular to a mobile off-grid energy storage system and a control method. Background Art

[0002] Off-grid energy storage technology refers to a power generation system that often does not rely on the power grid and operates independently. It is usually used in remote mountainous areas, areas without electricity, islands, communication base stations and street lights. The existing off-grid energy storage system is usually composed of a diesel generator, an inverter, a battery, a load, etc. The off-grid power generation system generates electricity through a diesel generator, supplies power to the load through an integrated inverter, and charges the battery at the same time. When the battery is fully charged, the battery supplies power to the AC load through the inverter. For example, patent publication number CN117728473A discloses an off-grid energy storage system and control method, including: a CPU main control system, a preset capacitor, a first power module, a second power module, a first control module, a second control module and a generator.

[0003] As a mature power generation equipment, diesel generators have been recognized by the market for their high thermal efficiency, wide power range, compact structure and lightweight design, quick start and easy operation, and are the preferred power generation equipment in places where electricity is scarce. However, diesel generators also have certain defects, such as high operation and maintenance costs, exhaust pollution and high noise. Summary of the invention

[0004] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a mobile off-grid energy storage system and a control method to solve the technical problems that the existing off-grid energy storage system relies on diesel generators for operation, has high operation and maintenance costs, and has high exhaust pollution and noise.

[0005] To achieve the above object, the present invention is implemented by adopting the following technical solutions: In a first aspect, the present invention provides a mobile off-grid energy storage system, comprising a mobile carrier and an energy storage unit, a box transformer system and a load interface arranged on the mobile carrier, the energy storage unit comprising a loadable battery system, the load interface comprising an external load interface and an internal load interface; the output end of the battery system is connected to the external load interface and the internal load interface via the box transformer system, the external load interface is used to supply power to an external load, the internal load interface is used to auxiliary power supply to the battery system and the box transformer system, and an auxiliary power supply switch is also provided between the internal load interface and the battery system.

[0006] The above-mentioned mobile off-grid energy storage system improves its mobility by placing the main components of the mobile off-grid energy storage system, such as the energy storage unit, the box transformer system, and the load interface, on a mobile carrier, making it easier to move in areas without power supply. The diesel generator configured in the traditional off-grid energy storage system is eliminated, overcoming the technical problems of high operation and maintenance costs, exhaust pollution, and high noise. At the same time, the battery system is loadable and can be replaced with load, solving the problem that the off-grid energy storage system cannot provide stable power to the back-end load for a long time without interruption.

[0007] Optionally, the energy storage unit also includes an energy storage inverter, and the battery system includes a battery stack. The battery stack and the energy storage inverter are arranged in pairs and are electrically connected through a quick-plug interface. The battery stack is used to provide direct current, and the energy storage inverter is used to convert the direct current into alternating current.

[0008] The battery stack and the energy storage inverter are electrically connected via a quick-plug interface, which enables rapid replacement of the battery system.

[0009] Optionally, a DC isolating switch and an AC circuit breaker are provided on the DC side and the AC side of the energy storage converter, respectively.

[0010] By setting up a DC isolating switch and an AC circuit breaker, the DC side and the AC side of the energy storage converter can be flexibly controlled to ensure that they are in the required working state.

[0011] Optionally, the mobile carrier is also provided with a backup battery system having the same configuration as the battery system.

[0012] The battery system is removable and can carry multiple backup battery systems for replacement to meet the long-term uninterrupted operation requirements of the off-grid energy storage system.

[0013] Optionally, the box transformer system includes a first transformer and a second transformer, wherein the first transformer is connected between the battery system and the external load interface, and the second transformer is connected between the battery system and the internal load interface.

[0014] Since the loads connected to the external load interface and the internal load interface are different and their operating voltages are also different, the first transformer and the second transformer are set to work separately and independently to avoid interference and facilitate management.

[0015] Optionally, output ends of the first transformer and the second transformer are both provided with protection circuit breakers.

[0016] By setting a protective circuit breaker, the energy storage unit and the load can be connected immediately when a fault occurs, thus playing a role in circuit safety protection.

[0017] Optionally, the mobile carrier is also provided with an energy storage system energy management module and a local control module and a box transformer control module electrically connected to the energy storage system energy management module. The energy storage system energy management module is used for data collection and control management of the local control module and the box transformer control module. The output ends of the local control module and the box transformer control module are respectively connected to the control ends of the energy storage unit and the box transformer system.

[0018] By setting up the energy management module, local control module and box-type transformer control module of the energy storage system, the entire mobile off-grid energy storage system is uniformly monitored and controlled to improve the overall user experience of the mobile off-grid energy storage system.

[0019] In a second aspect, the present invention provides a control method based on the above-mentioned mobile off-grid energy storage system, comprising: Add all energy storage units to the candidate list, start any energy storage unit in the candidate list, record it as the first energy storage unit and obtain the remaining power of its battery system in real time; initialization , set the power threshold and power threshold , , repeat the following steps: When The remaining power of the battery system of the energy storage unit is less than the power threshold When another energy storage unit in the candidate list is started, it is recorded as energy storage unit and obtain the remaining power of its battery system in real time; When The remaining power of the battery system of the energy storage unit is less than the power threshold When energy storage unit and disconnect the corresponding auxiliary power supply switch; The first Energy storage units are removed from the candidate list, .

[0020] By detecting the remaining power of the battery system during the operation of the energy storage unit, another energy storage unit is connected at an appropriate time according to the remaining power to replace the battery system. The overall performance of the mobile off-grid energy storage system is not affected during the replacement process, thereby solving the problem that the off-grid energy storage system cannot provide stable power to the back-end load uninterruptedly for a long time.

[0021] Optionally, the closing After the energy storage unit is connected and the corresponding auxiliary power supply switch is disconnected, Remove the battery system of the energy storage unit and install the backup battery system to the Energy storage unit or recharge the removed battery system and install it in the first Energy storage unit, Energy storage units have been added to the candidate list.

[0022] By removing battery systems with low power and replacing them with battery systems with sufficient power, the off-grid energy storage system can maintain long-term uninterrupted operation.

[0023] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a mobile off-grid energy storage system and control method. By setting a detachable battery system, a box transformer system and a load interface, a microgrid is established without relying on the power grid. The battery system can be replaced during the load process, so as to realize the function of the off-grid energy storage system to provide power to the load uninterruptedly for a long time. Multiple energy storage units in the system form an energy storage system with the box transformer system at the back end to supply power to the back end load at the same time or separately, and the battery system is switched on-load according to the remaining power of the battery system in operation.

[0024] At the same time, by placing the main components of the mobile off-grid energy storage system, such as the energy storage unit, box-type transformer system and load interface, on a mobile carrier, the mobility is improved, making it easier to move in areas without power supply. The diesel generator configured in the traditional off-grid energy storage system is eliminated, overcoming the technical problems of high operation and maintenance costs, exhaust pollution and high noise. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a structural schematic diagram of a mobile off-grid energy storage system provided by an embodiment of the present invention; Figure 2 is a connection diagram of an energy management module of an energy storage system provided by an embodiment of the present invention; Figure 3 It is a flow chart of a control method for a mobile off-grid energy storage system provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0026] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0027] Embodiment 1:

[0028] An embodiment of the present invention provides a mobile off-grid energy storage system, including a mobile carrier and an energy storage unit, a box transformer system and a load interface arranged on the mobile carrier, the energy storage unit includes a loadable battery system, and the load interface includes an external load interface and an internal load interface; the output end of the battery system is connected to the external load interface and the internal load interface via the box transformer system, the external load interface is used to supply power to an external load, and the internal load interface is used to provide auxiliary power supply to the battery system and the box transformer system, and an auxiliary power supply switch is also provided between the internal load interface and the battery system.

[0029] The mobile carrier can be a flatbed truck or other device that can be used to move in areas without power supply. The mobile carrier is also equipped with a backup battery system with the same configuration as the battery system. Since the battery system is removable, it can carry multiple backup battery systems for replacement to maintain the long-term uninterrupted operation of the off-grid energy storage system.

[0030] The energy storage unit also includes an energy storage inverter, and the battery system includes a battery stack. The battery stack and the energy storage inverter are arranged in pairs and are electrically connected through a quick-plug interface. The battery stack is used to provide direct current, and the energy storage inverter is used to convert direct current into alternating current.

[0031] like Figure 1 As shown, in the embodiment of the present invention, two energy storage units are selected as examples, each energy storage unit includes a battery system, each battery system includes n battery stacks, and the n battery stacks correspond to n energy storage converters (PCS1~PCSn). The battery stack and the energy storage converter are electrically connected through a quick-plug interface, which can achieve the purpose of quickly replacing the battery system.

[0032] The DC side and AC side of the energy storage converter are respectively provided with a DC isolating switch (QS1~QSn) and an AC circuit breaker (QF1~QFn). By providing the DC isolating switch and the AC circuit breaker, the DC side and the AC side of the energy storage converter can be flexibly switched on and off to ensure that they are in the required working state.

[0033] The box transformer system includes a first transformer T1 and a second transformer T2. The first transformer is connected between the battery system and the external load interface, and the second transformer is connected between the battery system and the internal load interface. The loads connected to the external load interface and the internal load interface are different. The loads connected to the external load interface are usually 220V AC input, such as mobile phone chargers, speakers, etc., while the loads connected to the internal load interface are usually low-voltage input, such as switching power supplies; their working voltages are different, so the first transformer and the second transformer are set to work separately and independently to avoid interference and facilitate management. The output ends of the first transformer and the second transformer are both provided with protective circuit breakers. By setting a protective circuit breaker, the connection between the energy storage unit and the load can be immediately disconnected in the event of a fault, which plays a role in circuit safety protection. In order to meet the working requirements, the capacity of the first transformer should be greater than or equal to the sum of the powers of the n energy storage converters of the energy storage unit 1; the second transformer supplies power to the equipment itself, and the capacity of the second transformer should be greater than or equal to the sum of the powers required by all the back-end equipment itself.

[0034] like Figure 2 As shown, the mobile carrier is also provided with an energy management module EMS of the energy storage system and a local control module LC and a box transformer control module MEU electrically connected to the energy management module EMS of the energy storage system. The energy management module EMS of the energy storage system is used for data collection and control management of the local control module LC and the box transformer control module MEU. The output ends of the local control module LC and the box transformer control module MEU are respectively connected to the control ends of the energy storage unit and the box transformer system. In this embodiment, two energy storage units are provided, so two local control modules LC1 and LC2 need to be provided. By providing the energy management module EMS of the energy storage system, the local control module LC and the box transformer control module EMU, the entire mobile off-grid energy storage system is uniformly monitored and controlled, thereby improving the overall user experience of the mobile off-grid energy storage system.

[0035] The above-mentioned mobile off-grid energy storage system improves its mobility by placing the main components of the mobile off-grid energy storage system, such as the energy storage unit, the box transformer system, and the load interface, on a mobile carrier, making it easier to move in areas without power supply. The diesel generator configured in the traditional off-grid energy storage system is eliminated, overcoming the technical problems of high operation and maintenance costs, exhaust pollution, and high noise. At the same time, the battery system is loadable and can be replaced with load, solving the problem that the off-grid energy storage system cannot provide stable power to the back-end load for a long time without interruption.

[0036] Embodiment 2: like Figure 3 As shown, an embodiment of the present invention provides a control method based on the above-mentioned mobile off-grid energy storage system, comprising the following steps: Add all energy storage units to the candidate list, start any energy storage unit in the candidate list, record it as the first energy storage unit and obtain the remaining power of its battery system in real time; initialization , set the power threshold and power threshold , , repeat the following steps: When The remaining power of the battery system of the energy storage unit is less than the power threshold When another energy storage unit in the candidate list is started, it is recorded as energy storage unit and obtain the remaining power of its battery system in real time; When The remaining power of the battery system of the energy storage unit is less than the power threshold When energy storage unit and disconnect the corresponding auxiliary power supply switch; The first Energy storage units are removed from the candidate list, .

[0037] Close After the energy storage unit is connected and the corresponding auxiliary power supply switch is disconnected, Remove the battery system of the energy storage unit and install the backup battery system to the Energy storage unit or recharge the removed battery system and install it in the first Energy storage unit, Energy storage units have been added to the candidate list.

[0038] Furthermore, an early warning mechanism can be set up as needed. When the number of energy storage units in the standby list is less than a preset number, an alarm reminder is issued to let the staff know that if the battery system cannot be replenished immediately, the mobile off-grid energy storage system will stop working.

[0039] By detecting the remaining power of the battery system during the operation of the energy storage unit, another energy storage unit is connected at an appropriate time according to the remaining power to replace the battery system. The overall performance of the mobile off-grid energy storage system is not affected during the replacement process, thereby solving the problem that the off-grid energy storage system cannot provide stable power to the back-end load uninterruptedly for a long time.

[0040] Taking two energy storage units as an example, the local control module LC1 controls the isolation switches of each stack of the battery system 1 to close to supply power to the corresponding PCS. After the DC side of n PCS is energized, the AC switches QF1~QFn are closed, and the output is stable in VF mode. The external power supply interface and the internal power supply interface are powered through the first transformer and the second transformer. The n PCSs jointly and dynamically track the total power Pload of the load, where the power provided by each PCS is Pload / n.

[0041] The energy storage system composed of energy storage unit 1 and box transformer system continuously provides power to the load. The energy management module EMS of the energy storage system detects the power of battery system 1 in real time. When the power of battery system 1 is less than the power threshold (For example, 10%) When 10%, the local control module LC2 controls the isolation switches of each stack of battery system 2 to close and supply power to the corresponding PCS. After the DC sides of n PCSs are energized, the AC switches QFn+1~QF2n are closed and the output voltage is stable in VF mode. At this time, the energy storage unit 1 and the energy storage unit 2 evenly share the total load power Pload, and the power provided by each PCS is Pload / 2n.

[0042] The energy management module EMS of the energy storage system detects that the power of the battery system 1 is less than the power threshold When the power consumption of the energy storage unit 1 reaches 5%, the local control module LC1 controls the energy storage unit 1 to shut down, and the energy management module EMS of the energy storage system disconnects the auxiliary power supply switch of the battery system 1. At this time, the power required by the load is all provided by the energy storage system composed of the energy storage unit 2 and the box transformer system; the battery system 1 is removed, the battery system 3 is connected to the energy storage unit 1, and the removed battery system 1 is transported to an area with a power grid for recharging.

[0043] After the battery system 1 is fully charged, it is transported back as a backup for the energy storage system. The above steps are repeated to enable the energy storage system to continuously provide reliable power to the load.

[0044] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0045] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0046] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0047] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0048] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A mobile off-grid energy storage system, characterized in that: It includes a mobile carrier and an energy storage unit, a box transformer system and a load interface arranged on the mobile carrier, the energy storage unit includes a loadable battery system, and the load interface includes an external load interface and an internal load interface; the output end of the battery system is connected to the external load interface and the internal load interface through the box transformer system, the external load interface is used to supply power to an external load, and the internal load interface is used to provide auxiliary power to the battery system and the box transformer system, and an auxiliary power supply switch is also provided between the internal load interface and the battery system.

2. The mobile off-grid energy storage system according to claim 1, characterized in that: The energy storage unit also includes an energy storage inverter, and the battery system includes a battery stack. The battery stack and the energy storage inverter are arranged in pairs and are electrically connected through a quick-plug interface. The battery stack is used to provide direct current, and the energy storage inverter is used to convert the direct current into alternating current.

3. The mobile off-grid energy storage system according to claim 2, characterized in that: The DC side and AC side of the energy storage converter are respectively provided with a DC isolating switch and an AC circuit breaker.

4. The mobile off-grid energy storage system according to claim 1, characterized in that: The mobile carrier is also provided with a backup battery system having the same configuration as the battery system.

5. The mobile off-grid energy storage system according to claim 1, characterized in that: The box transformer system includes a first transformer and a second transformer, wherein the first transformer is connected between the battery system and the external load interface, and the second transformer is connected between the battery system and the internal load interface.

6. The mobile off-grid energy storage system according to claim 5, characterized in that: The output ends of the first transformer and the second transformer are both provided with protection circuit breakers.

7. The mobile off-grid energy storage system according to claim 1, characterized in that: The mobile carrier is also provided with an energy storage system energy management module and a local control module and a box transformer control module electrically connected to the energy storage system energy management module. The energy storage system energy management module is used for data collection and control management of the local control module and the box transformer control module. The output ends of the local control module and the box transformer control module are respectively connected to the control ends of the energy storage unit and the box transformer system.

8. A control method for a mobile off-grid energy storage system according to any one of claims 1 to 7, characterized in that: include: Add all energy storage units to the candidate list, start any energy storage unit in the candidate list, record it as the first energy storage unit and obtain the remaining power of its battery system in real time; initialization , set the power threshold and power threshold , , repeat the following steps: When The remaining power of the battery system of the energy storage unit is less than the power threshold When another energy storage unit in the candidate list is started, it is recorded as energy storage unit and obtain the remaining power of its battery system in real time; When The remaining power of the battery system of the energy storage unit is less than the power threshold When energy storage unit and disconnect the corresponding auxiliary power supply switch; The first Energy storage units are removed from the candidate list, .

9. The control method of the mobile off-grid energy storage system according to claim 8, characterized in that: The closure After the energy storage unit is connected and the corresponding auxiliary power supply switch is disconnected, Remove the battery system of the energy storage unit and install the backup battery system to the Energy storage unit or recharge the removed battery system and install it in the first Energy storage unit, Energy storage units have been added to the candidate list.

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