Distributed energy system and operation method thereof
The distributed energy system optimizes power dispatch among interconnected units, addressing inefficiencies in existing energy-storage cabinets by coordinating power allocation through a network-connected system, thereby enhancing power-use efficiency.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- GOODRICH PLUS ENERGY TECHNOLOGY LLC
- Filing Date
- 2025-11-27
- Publication Date
- 2026-06-11
AI Technical Summary
Existing household energy-storage cabinets lack intelligent power-dispatch strategies, leading to inefficient utilization of power resources during peak-demand seasons and power outages.
A distributed energy system comprising a monitoring terminal device, energy storage main unit, bidirectional DC charging devices, and energy storage sub-units, which communicate and coordinate power dispatch through a network-connected system to optimize power allocation among units.
Enables efficient utilization of reserve power by dispatching power from energy storage sub-units with sufficient capacity to those with insufficient capacity, enhancing power-use efficiency during demand fluctuations.
Smart Images
Figure US2025057390_11062026_PF_FP_ABST
Abstract
Description
[0001] DISTRIBUTED ENERGY SYSTEM AND OPERATION METHOD THEREOF
[0002] BACKGROUND OF THE INVENTION
[0003] Related Application
[0004] This application claims priority to Taiwan Invention Patent Application No. 113146495, filed on December 2, 2024, entitled “DISTRIBUTED ENERGY SYSTEM AND OPERATION METHOD THEREOF.” and Taiwan Utility Model Application No. 113213181, filed on December 2, 2024, entitled “DISTRIBUTED ENERGY SYSTEM.” The entire contents of each of the foregoing applications are incorporated herein by reference in their entirety.
[0005] Field of the Invention
[0006] The present disclosure relates to an energy management system and a method of operation thereof, and more particularly to a distributed energy system and a method of operation thereof.
[0007] Description of Related Art
[0008] With the proliferation of Intemet-of-Things (loT) products, household electricity consumption continues to increase. Accordingly, during peak-demand seasons, the frequency of power outages or circuit-breaker trips keeps rising. To cope with unexpected outages and trips, many manufacturers have developed energy-storage cabinets. An energy-storage cabinet is provided with rechargeable batteries. When utility power is normal, the utility power charges the energy-storage cabinet; when an outage or a breaker trip occurs, the energy-storage cabinet activates a power-supply mechanism. However, existing household energy-storage cabinets merely charge from utility power and supply electricity to household appliances, and do not incorporate intelligent power-dispatch strategies. Therefore, there remains substantial room for improvement in efficiently utilizing power resources.
[0009] SUMMARY
[0010] The technical problem addressed by the present disclosure is to remedy the deficiencies of the prior art by providing a distributed energy system and a method of operation thereof. To solve the foregoing problem, one technical solution of the present disclosure provides a distributed energy system. The distributed energy system includes a monitoring terminal device, an energy storage main unit, a plurality of bidirectional DC charging devices, and a plurality of energy storage sub-units. The energy storage main unit is network-connected to the monitoring terminal device and transmits a main-unit status to the monitoring terminal device. The plurality of bidirectional DC charging devices are coupled to the energy storage main unit, are respectively network-connected to the monitoring terminal device, and each transmits a charging-device status to the monitoring terminal device. The plurality of energy storage sub-units are respectively coupled to the plurality of bidirectional DC charging devices, are respectively network-connected to the monitoring terminal device, and each transmits a sub-unit status to the monitoring terminal device. The monitoring terminal device is configured to, according to the main-unit status, the plurality of charging-device statuses, and the plurality of sub-unit statuses, instruct power dispatch between the energy storage main unit and at least one energy storage sub-unit or stop power dispatch.
[0011] To solve the foregoing problem, another technical solution of the present disclosure provides a method of operating a distributed energy system, including: by the energy storage main unit, network-connecting to the monitoring terminal device and transmitting the main-unit status to the monitoring terminal device; by the plurality of bidirectional DC charging devices, networkconnecting to the monitoring terminal device and each transmitting a charging-device status to the monitoring terminal device; by the plurality of energy storage sub-units, network-connecting to the monitoring terminal device and each transmitting a sub-unit status to the monitoring terminal device; and, by the monitoring terminal device, according to the main-unit status, the plurality of charging-device statuses, and the plurality of sub-unit statuses, instructing power dispatch between the energy storage main unit and at least one energy storage sub-unit or stopping power dispatch.
[0012] One advantageous effect of the present disclosure is that, through the distributed energy system and the method of operation provided herein, when the capacity of an energy storage subunit is insufficient, the energy storage main unit can, via a bidirectional DC charging device, dispatch power from an energy storage sub-unit with sufficient capacity to the energy storage subunit with insufficient capacity. Accordingly, reserve power of the energy storage sub-units can be allocated according to power-use demand, enabling more efficient utilization of the reserve power. The following detailed description and drawings relate to the present disclosure; however, the drawings are provided for reference and illustration only, and are not intended to limit the present disclosure.
[0013] BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a functional block diagram of a distributed energy system according to an embodiment of the present disclosure.
[0015] FIG. 2 is a functional block diagram of the energy storage main unit of FIG. 1.
[0016] FIG. 3 is a functional block diagram of the battery management system of FIG. 2.
[0017] FIG. 4 is a functional block diagram of the bidirectional DC charging device of FIG. 1.
[0018] FIG. 5 is a functional block diagram of the energy storage sub-unit of FIG. 1.
[0019] FIG. 6 is a functional block diagram of the battery management system of FIG. 5.
[0020] FIG. 7 is a flowchart of a method of operating a distributed energy system according to a first embodiment of the present disclosure.
[0021] FIG. 8 is a flowchart of a method of operating a distributed energy system according to a second embodiment of the present disclosure.
[0022] FIG. 9 is a flowchart of a method of operating a distributed energy system according to a third embodiment of the present disclosure.
[0023] FIG. 10 is a flowchart of a method of operating a distributed energy system according to a fourth embodiment of the present disclosure.
[0024] FIG. 11 is a flowchart of a method of operating a distributed energy system according to a fifth embodiment of the present disclosure.
[0025] FIG. 12 is a flowchart of a method of operating a distributed energy system according to a sixth embodiment of the present disclosure.
[0026] DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0027] The embodiments disclosed below illustrate implementations of the “distributed energy system and method of operation thereof’ of the present disclosure, enabling those skilled in the art to understand the advantages and effects from the teachings herein. The present disclosure may be practiced or applied through other different specific embodiments, and the various details in this specification may be modified and altered from different viewpoints and applications without departing from the spirit of the present disclosure. In addition, the drawings of the present disclosure are merely simplified schematic illustrations rather than depictions to actual scale, as hereby stated in advance. The following embodiments further describe the relevant technical content of the present disclosure in detail; however, the disclosed content is not intended to limit the scope of protection of the present disclosure.
[0028] It should be understood that although terms such as “first,” “second,” and “third” may be used herein to describe various elements or signals, such elements or signals are not limited by these terms. The terms are used primarily to distinguish one element from another, or one signal from another. In addition, the term “or” as used herein should be interpreted, depending on the context, to include any one of the listed items or any combination of two or more of the listed items.
[0029] FIG. 1 is a functional block diagram of a distributed energy system according to an embodiment of the present disclosure. Referring to FIG. 1, the distributed energy system 100 includes a monitoring terminal device 1, an energy storage main unit 2, a plurality of bidirectional DC charging devices 3, and a plurality of energy storage sub-units 4. The plurality of bidirectional DC charging devices 3 are coupled to the energy storage main unit 2 via multiple different cables, and the plurality of energy storage sub-units 4 are respectively coupled to the plurality of bidirectional DC charging devices 3 via multiple different cables. The energy storage main unit 2 is further coupled to a utility power grid E, and the plurality of energy storage subunits 4 are respectively coupled to a plurality of loads L. The energy storage main unit 2, the plurality of bidirectional DC charging devices 3, and the plurality of energy storage sub-units 4 are network-connected to the monitoring terminal device 1.
[0030] The monitoring terminal device 1, the energy storage main unit 2, the plurality of bidirectional DC charging devices 3, and the plurality of energy storage sub-units 4 are, for example, within the same network domain. Specifically, the monitoring terminal device 1, the energy storage main unit 2, the plurality of bidirectional DC charging devices 3, and the plurality of energy storage sub-units 4 are coupled to a network switch, and the network switch is connected to the Internet.
[0031] The monitoring terminal device 1, the energy storage main unit 2, the plurality of bidirectional DC charging devices 3, and the plurality of energy storage sub-units 4 are, for example, respectively located in different network domains. Specifically, the monitoring terminal device 1, the energy storage main unit 2, the plurality of bidirectional DC charging devices 3, and the plurality of energy storage sub-units 4 are respectively coupled to a plurality of routers, and the plurality of routers are connected to the Internet.
[0032] The energy storage main unit 2 transmits a main-unit status to the monitoring terminal device 1 at each fixed interval. Each bidirectional DC charging device 3 transmits a chargingdevice status to the monitoring terminal device 1 at each fixed interval, and each energy storage sub-unit 4 transmits a sub-unit status to the monitoring terminal device 1 at each fixed interval. The monitoring terminal device 1 is configured to, based on the main-unit status, the plurality of charging-device statuses, and the plurality of sub-unit statuses, instruct the energy storage main unit 2 and at least one energy storage sub-unit 4 to perform power dispatch between them, or to stop power dispatch.
[0033] FIG. 2 is a functional block diagram of the energy storage main unit 2 of FIG. 1. The energy storage main unit 2 includes a processor 21, a chipset 22, a memory 23, a network interface 24, a battery pack 25, a battery management system 26, a first switch 27, and a second switch 28. The processor 21 is coupled to the chipset 22 and the battery management system 26. The chipset 22 is coupled to the memory 23, the network interface 24, the first switch 27, and the second switch 28. The battery pack 25 includes a plurality of series-connected batteries, and the battery management system 26 is coupled to the battery pack 25. The first switch 27 is coupled to the battery pack 25 and the plurality of bidirectional DC charging devices 3, and the second switch 28 is coupled to the utility power grid E and the plurality of bidirectional DC charging devices 3.
[0034] FIG. 3 is a functional block diagram of the battery management system 26 of FIG. 2. Referring to FIG. 3, the battery management system 26 includes a microcontroller 261, a voltage measurement circuit 262, a temperature sampling circuit 263, and a current sampling circuit 264. The microcontroller 261 is coupled to the voltage measurement circuit 262, the temperature sampling circuit 263, and the current sampling circuit 264, and the voltage measurement circuit 262, the temperature sampling circuit 263, and the current sampling circuit 264 are coupled to the battery pack 25. The battery management system 26 is configured to detect a capacity, a current, a voltage, and a temperature of the battery pack 25.
[0035] When the battery management system 26 detects that any one of the capacity, current, voltage, or temperature of the battery pack 25 is in an abnormal state, the chipset 22 controls the first switch 27 to switch from an on-state to an off-state, and controls the second switch 28 to switch from an off-state to an on-state. The abnormal state may include, for example, the capacity percentage of the battery pack 25 being lower than a threshold percentage, the current or the voltage of the battery pack 25 exceeding a normal operating range, or the temperature of the battery pack 25 exceeding a normal operating range. In this case, the battery pack 25 of the energy storage main unit 2 stops supplying power to the bidirectional DC charging devices 3 and instead delivers DC power from the utility power grid E to the bidirectional DC charging devices 3.
[0036] FIG. 4 is a functional block diagram of the bidirectional DC charging device 3 of FIG. 1. Referring to FIG. 4, the bidirectional DC charging device 3 includes a processor 31, a chipset 32, a memory 33, a network interface 34, a bidirectional DC converter 35, a first switch 36, and a second switch 37, and the processor 31 is coupled to the chipset 32. The chipset 32 is coupled to the memory 33, the network interface 34, the first switch 36, and the second switch 37. The first switch 36 is coupled to the chipset 32 and is coupled between a first end of the bidirectional DC converter 35 and the energy storage main unit 2. The second switch 37 is coupled to the chipset 32 and is coupled between a second end of the bidirectional DC converter 35 and the energy storage sub-unit 4.
[0037] FIG. 5 is a functional block diagram of the energy storage sub-unit 4 of FIG. 1. Referring to FIG. 5, the energy storage sub-unit 4 includes a processor 41, a chipset 42, a memory 43, a network interface 44, a battery 45, a battery management system 46, and a first switch 47. The processor 41 is coupled to the chipset 42 and the battery management system 46. The chipset 42 is coupled to the memory 43, the network interface 44, and the first switch 47. The battery management system 46 is coupled to the battery 45, and the first switch 47 is coupled to the load L and the battery 45.
[0038] FIG. 6 is a functional block diagram of the battery management system 46 of FIG. 5. Referring to FIG. 6, the battery management system 46 includes a microcontroller 461, a voltage measurement circuit 462, a temperature sampling circuit 463, and a current sampling circuit 464. The microcontroller 461 is coupled to the voltage measurement circuit 462, the temperature sampling circuit 463, and the current sampling circuit 464, and the voltage measurement circuit 462, the temperature sampling circuit 463, and the current sampling circuit 464 are coupled to the battery 45. The battery management system 46 is configured to detect a capacity, a current, a voltage, and a temperature of the battery 45.
[0039] When the battery management system 46 detects that any one of the capacity, current, voltage, or temperature of the battery 45 is in an abnormal state, the chipset 42 controls the first switch 47 to switch from an on-state to an off-state. The abnormal state may include, for example, the capacity percentage of the battery 45 being lower than a threshold percentage, the current or the voltage of the battery 45 exceeding a normal operating range, or the temperature of the battery 45 exceeding a normal operating range. At this time, the battery 45 of the energy storage sub-unit 4 stops supplying power to the load L.
[0040] FIG. 7 is a flowchart of a method of operating a distributed energy system according to a first embodiment of the present disclosure. In step SI 01, by the energy storage main unit 2, network-connecting to the monitoring terminal device 1 and transmitting a main-unit status to the monitoring terminal device 1. In step SI 02, by the plurality of bidirectional DC charging devices 3, network-connecting to the monitoring terminal device 1 and respectively transmitting a plurality of charging-device statuses to the monitoring terminal device 1. In step SI 03, by the plurality of energy storage sub-units 4, network-connecting to the monitoring terminal device 1 and respectively transmitting a plurality of sub-unit statuses to the monitoring terminal device 1. In step SI 04, by the monitoring terminal device 1, according to the main-unit status, the plurality of charging-device statuses, and the plurality of sub-unit statuses, instructing power dispatch between the energy storage main unit 2 and at least one energy storage sub-unit 4, or stopping power dispatch.
[0041] FIG. 8 is a flowchart of a method of operating a distributed energy system according to a second embodiment of the present disclosure. With reference to FIGS. 4 and 8 together, in step S201, the bidirectional DC charging device 3 performs power dispatch between the energy storage sub-unit 4 and the energy storage main unit 2. At this time, the first switch 36 and the second switch 37 of the bidirectional DC charging device 3 are in an on-state. In step S202, an abnormal condition occurs in the energy storage sub-unit 4. In step S203, the monitoring terminal device 1 notifies the bidirectional DC charging device 3 of the abnormal event of the energy storage sub-unit 4. In step S204, the chipset 32 of the bidirectional DC charging device 3 controls the second switch 37 to switch from the on-state to an off-state. In other words, the bidirectional DC charging device 3 disconnects a power path between the energy storage sub- unit 4 and the bidirectional DC charging device 3 so as to stop power dispatch between the energy storage sub-unit 4 and the energy storage main unit 2.
[0042] FIG. 9 is a flowchart of a method of operating a distributed energy system according to a third embodiment of the present disclosure. With reference to FIGS. 4 and 9 together, in step S301, the bidirectional DC charging device 3 performs power dispatch between the energy storage sub-unit 4 and the energy storage main unit 2. In step S302, an abnormal condition occurs in the energy storage main unit 2. In step S303, the monitoring terminal device 1 notifies the bidirectional DC charging device 3 of the abnormal event of the energy storage main unit 2. In step S304, the chipset 32 of the bidirectional DC charging device 3 controls the first switch 36 to switch from an on-state to an off-state. In other words, the bidirectional DC charging device 3 disconnects a power path between the energy storage main unit 2 and the bidirectional DC charging device 3 so as to stop power dispatch between the energy storage sub-unit 4 and the energy storage main unit 2.
[0043] FIG. 10 is a flowchart of a method of operating a distributed energy system according to a fourth embodiment of the present disclosure. With reference to FIGS. 4 and 10 together, in step S401, the bidirectional DC charging device 3 performs power dispatch between the energy storage sub-unit 4 and the energy storage main unit 2. In step S402, a network connection between the bidirectional DC charging device 3 and the monitoring terminal device 1 is interrupted. In step S403, the chipset 32 of the bidirectional DC charging device 3 controls the first switch 36 and the second switch 37 to switch from on-states to off-states. In other words, the bidirectional DC charging device 3 disconnects a power path between the energy storage main unit 2 and the bidirectional DC charging device 3 and disconnects a power path between the energy storage sub-unit 4 and the bidirectional DC charging device 3, so as to stop power dispatch between the energy storage sub-unit 4 and the energy storage main unit 2.
[0044] FIG. 11 is a flowchart of a method of operating a distributed energy system according to a fifth embodiment of the present disclosure. With reference to FIGS. 1 and 10 together, in step S501, the monitoring terminal device 1, based on the sub-unit status, learns that a capacity percentage of the energy storage sub-unit 4 is lower than a threshold percentage. In step S502, the monitoring terminal device 1 sends commands to two bidirectional DC charging devices 3, wherein one bidirectional DC charging device 3 corresponds to the energy storage sub-unit 4 whose capacity percentage is lower than the threshold percentage, and the other bidirectional DC charging device 3 corresponds to the energy storage sub-unit 4 whose capacity percentage is higher than the threshold percentage. In step S503, the chipset 32 of each bidirectional DC charging device 3 controls the first switch 36 and the second switch 37 to switch from off-states to on-states according to the command of the monitoring terminal device 1. In step S504, the energy storage sub-unit 4 whose capacity percentage is higher than the threshold percentage dispatches power, via the two bidirectional DC charging devices 3 and the energy storage main unit 2, to the energy storage sub-unit 4 whose capacity percentage is lower than the threshold percentage.
[0045] FIG. 12 is a flowchart of a method of operating a distributed energy system according to a sixth embodiment of the present disclosure. With reference to FIGS. 1 and 10 together, in step S601, the monitoring terminal device 1, based on the sub-unit status, learns that a capacity percentage of an energy storage sub-unit 4 is lower than a threshold percentage. In step S602, the monitoring terminal device 1 sends commands to three bidirectional DC charging devices 3, wherein one bidirectional DC charging device 3 corresponds to the energy storage sub-unit 4 whose capacity percentage is lower than the threshold percentage, and the other two bidirectional DC charging devices 3 respectively correspond to two energy storage sub-units 4 whose capacity percentages are higher than the threshold percentage. In step S603, the chipset 32 of each bidirectional DC charging device 3 controls the first switch 36 and the second switch 37 to switch from off-states to on-states according to the command of the monitoring terminal device 1. In step S604, the two energy storage sub-units 4 whose capacity percentages are higher than the threshold percentage dispatch power, via the three bidirectional DC charging devices 3 and the energy storage main unit 2, to the energy storage sub-unit 4 whose capacity percentage is lower than the threshold percentage.
[0046] Advantageous Effects of the Embodiments
[0047] One advantageous effect of the present disclosure is that, through the distributed energy system and the method of operation provided herein, when the capacity of an energy storage subunit is insufficient, the energy storage main unit can, via a bidirectional DC charging device, dispatch power from other energy storage sub-units to the energy storage sub-unit whose capacity is insufficient. Accordingly, reserve power of the energy storage sub-units can be allocated according to power-use demand, enabling more efficient utilization of the reserve power. The foregoing disclosure merely describes preferred and feasible embodiments and is not intended to limit the scope of the present application. Any equivalent technical modifications or changes made based on the contents of this specification and the drawings are encompassed within the scope of the present application.
Claims
WHAT IS CLAIMED IS:
1. A distributed energy system, comprising: a monitoring terminal device; an energy storage main unit that is network-connected to the monitoring terminal device and transmits a main-unit status to the monitoring terminal device; a plurality of bidirectional DC charging devices coupled to the energy storage main unit, each of the bidirectional DC charging devices being network-connected to the monitoring terminal device and transmitting a charging-device status to the monitoring terminal device; a plurality of energy storage sub-units respectively coupled to the plurality of bidirectional DC charging devices, each of the energy storage sub-units being network-connected to the monitoring terminal device and transmitting a sub-unit status to the monitoring terminal device; and wherein the monitoring terminal device is configured to, based on the main-unit status, the plurality of charging-device statuses, and the plurality of sub-unit statuses, instruct power dispatch between the energy storage main unit and at least one of the energy storage subunits or stop the power dispatch;2. The distributed energy system of claim 1, wherein each of the bidirectional DC charging devices comprises a bidirectional DC converter, a first switch, and a second switch, the first switch being coupled to the bidirectional DC converter and the energy storage main unit, and the second switch being coupled to the bidirectional DC converter and one of the energy storage sub-units; wherein, when the energy storage main unit is abnormal, the first switch switches from an on-state to an off-state; and when the energy storage sub-unit is abnormal, the second switch switches from the on-state to the off-state.
3. The distributed energy system of claim 2, wherein each of the bidirectional DC charging devices comprises a processor, a chipset, a memory, and a network interface, the processor being coupled to the chipset, the chipset being coupled to the memory and the network interface, and the first switch and the second switch being coupled to the chipset.
4. The distributed energy system of claim 1, wherein the energy storage main unit comprises a battery pack, a battery management system, a first switch, and a second switch, the battery pack being coupled to the battery management system, the first switch being coupled to the battery pack and the plurality of bidirectional DC charging devices, and the second switch being coupled to a utility power grid and the plurality of bidirectional DC charging devices; wherein, when the battery pack is abnormal, the first switch switches from an on-state to an off-state, and the second switch switches from the off-state to the on-state.
5. The distributed energy system of claim 4, wherein the battery management system comprises a microcontroller, a voltage measurement circuit, a temperature sampling circuit, and a current sampling circuit, the microcontroller being coupled to the voltage measurement circuit, the temperature sampling circuit, and the current sampling circuit, and the voltage measurement circuit, the temperature sampling circuit, and the current sampling circuit being coupled to the battery pack.
6. The distributed energy system of claim 4, wherein the energy storage main unit comprises a processor, a chipset, a memory, and a network interface, the processor being coupled to the chipset and the battery management system, and the chipset being coupled to the memory, the network interface, the first switch, and the second switch.
7. The distributed energy system of claim 1, wherein each energy storage sub-unit comprises a battery, a battery management system, and a first switch, the battery being coupled to the battery management system and one of the bidirectional DC charging devices, and the first switch being coupled to the battery and a load; wherein, when power dispatch between the energy storage sub-unit and the energy storage main unit is being performed, the first switch is in an off-state; and when the power dispatch is stopped, the first switch switches from the off-state to an on-state.
8. The distributed energy system of claim 7, wherein the battery management system comprises a microcontroller, a voltage measurement circuit, a temperature sampling circuit, and a current sampling circuit, the microcontroller being coupled to the voltagemeasurement circuit, the temperature sampling circuit, and the current sampling circuit, and the voltage measurement circuit, the temperature sampling circuit, and the current sampling circuit being coupled to the battery.
9. The distributed energy system of claim 7, wherein the energy storage sub-unit comprises a processor, a chipset, a memory, and a network interface, the processor being coupled to the chipset and the battery management system, and the chipset being coupled to the memory, the network interface, the battery management system, and the first switch.
10. The distributed energy system of claim 1, wherein, when capacity percentages of two of the energy storage sub-units are respectively lower than a threshold percentage and not lower than the threshold percentage, the energy storage sub-unit whose capacity percentage is not lower than the threshold percentage is configured to dispatch power to the energy storage sub-unit whose capacity percentage is lower than the threshold percentage via a corresponding one of the bidirectional DC charging devices, the energy storage main unit, and a corresponding one of the bidirectional DC charging devices of the energy storage subunit whose capacity percentage is lower than the threshold percentage.
11. A method of operating a distributed energy system, comprising: by an energy storage main unit, network-connecting to a monitoring terminal device and transmitting a main-unit status to the monitoring terminal device; by a plurality of bidirectional DC charging devices, network-connecting to the monitoring terminal device and each transmitting a charging-device status to the monitoring terminal device; by a plurality of energy storage sub-units, network-connecting to the monitoring terminal device and each transmitting a sub-unit status to the monitoring terminal device; and by the monitoring terminal device, according to the main-unit status, the plurality of chargingdevice statuses, and the plurality of sub-unit statuses, instructing power dispatch between the energy storage main unit and at least one of the energy storage sub-units or stopping the power dispatch;12. The method of claim 11, wherein, when the energy storage main unit is abnormal, the bidirectional DC charging device disconnects a power path between the energy storage main unit and the bidirectional DC charging device; and when the energy storage sub-unit is abnormal, the bidirectional DC charging device disconnects a power path between the energy storage sub-unit and the bidirectional DC charging device.
13. The method of claim 11, wherein, when capacity percentages of two of the energy storage sub-units are respectively lower than a threshold percentage and not lower than the threshold percentage, the energy storage sub-unit whose capacity percentage is not lower than the threshold percentage dispatches power to the energy storage sub-unit whose capacity percentage is lower than the threshold percentage via a corresponding one of the bidirectional DC charging devices, the energy storage main unit, and a corresponding one of the bidirectional DC charging devices of the energy storage sub-unit whose capacity percentage is lower than the threshold percentage.