Energy storage device with immersed liquid cooling function

Abstract

The invention provides an energy storage device with an immersed liquid cooling function, which comprises an energy storage battery pack, a high-voltage box, an energy storage converter and a BMS system which are connected in sequence, and is characterized in that the BMS system is used for monitoring an SOC value and temperature abnormal information of the energy storage battery pack; the energy storage converter is connected to a power grid power supply end and forms a common connection point, the power grid power supply end is used for being connected with a power grid for power supply, and the power grid power supply end is connected with a current transformer for detecting fault information of the power grid. The power supply end of the power grid is also connected with a first static change-over switch which is used for controlling the power supply end of the power grid and the energy storage converter to be in grid-connected power supply or off-grid power supply; the common connection point is connected with a first power supply loop for supplying power to a common load and a second power supply loop for supplying power to a key load, and the second power supply loop is connected with a main UPS power supply for supplying power to the key load; and a detection control unit is connected between the energy storage converter and the power supply end of the power grid. According to the invention, uninterrupted power supply for the key load can be ensured.

Description

Technical Field

[0001] This invention relates to the field of energy storage system technology, and in particular to an energy storage device with immersion liquid cooling function. Background Technology

[0002] With the rapid development of energy storage technology, the application scope of battery energy storage systems is gradually expanding. Simultaneously, as the power and energy density of battery energy storage systems continue to increase, the requirements for their thermal management efficiency and reliability are becoming increasingly stringent. Thermal runaway is currently the most common fault in energy storage systems. When thermal runaway or other faults occur, it is necessary to disconnect the energy storage system from the grid. Alternatively, when the remaining power of the energy storage system is insufficient or a grid fault occurs, power switching is also required. During power switching, load power outages may occur. However, critical loads such as servers and data centers require uninterrupted power supply, thus limiting the application of energy storage systems in these scenarios. Summary of the Invention

[0003] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide an energy storage device with immersion liquid cooling function, which has the advantage of being able to achieve uninterrupted power supply.

[0004] To achieve the above and other related objectives, the present invention provides the following technical solution: An energy storage device with immersion liquid cooling function includes an energy storage battery pack, a high-voltage box, an energy storage converter and a BMS system connected in sequence. The BMS system is used to monitor the SOC value and temperature anomaly information of the energy storage battery pack. The energy storage converter is connected to the power grid supply end and forms a common connection point. The power grid supply end is used to connect to the power grid for power supply. The power grid supply end is connected to a current transformer for detecting fault information of the power grid. The power grid supply end is also connected to a first static transfer switch for controlling the power grid supply end to be connected to the power grid or disconnected from the power grid. The common connection point is connected to a first power supply circuit that supplies power to general loads and a second power supply circuit that supplies power to critical loads. The second power supply circuit is connected to the main UPS power supply for supplying power to critical loads. A detection and control unit is connected between the energy storage converter and the grid power supply terminal. The detection and control unit is connected to the BMS system and the current transformer. The detection and control unit is configured to: During the power supply process of the energy storage battery pack, if the SOC value is detected to be less than the low capacity warning threshold or the temperature abnormality information continues to be generated for more than the high temperature warning duration, the first static transfer switch is controlled to activate the grid power supply terminal to connect to the grid and the energy storage battery pack is controlled to stop supplying power through the BMS system. If fault information detected by the current transformer is collected during the power supply process at the grid power supply end, the first static transfer switch is controlled to disconnect the grid power supply end from the grid, and the energy storage battery pack is controlled to start power supply through the BMS system.

[0005] To achieve the above technical solution, typically, during peak electricity hours, power is supplied primarily by energy storage battery packs, while during off-peak hours, power is supplied primarily by the grid and the energy storage battery packs are charged, thereby saving electricity costs. When the energy storage battery packs are supplying power, the high-voltage switchgear handles the access and distribution of power, and then the energy storage converter performs conversion and regulation to supply power to the load, managed and controlled by the BMS system. When power is supplied from the grid, the BMS system controls the energy storage battery packs to shut down or charge. Power is supplied directly to general loads in the first power supply circuit, and in the second power supply circuit... After the power circuit is processed by the UPS power supply, it supplies power to the critical load. When the grid connection needs to be switched due to peak-valley changes, grid failures, insufficient power of the energy storage battery pack, or thermal runaway of the energy storage system, the first static transfer switch switches the state to realize grid connection or off-grid power supply at the grid power supply end. The BMS system controls the energy storage battery pack to supply power or off-grid. Because the first static transfer switch can realize fast power switching, general loads can achieve seamless switching at the millisecond level. On the second power supply circuit, due to the role of the UPS power supply, uninterrupted power supply to the critical load can be guaranteed.

[0006] In one embodiment of the present invention, the energy storage battery pack adopts an immersion liquid cooling cycle subsystem, and the BMS system is used to collect the first temperature information of each single cell of the energy storage battery pack and the second temperature information of the immersion coolant. The BMS system is configured to generate the temperature anomaly information when the first temperature information exceeds a first high temperature threshold and the second temperature information exceeds a second high temperature threshold, or to generate the temperature anomaly information when the first temperature information exceeds the first high temperature threshold and the duration exceeds a first duration.

[0007] To achieve the above technical solution, when the first temperature information exceeds the first high temperature threshold, it indicates that the cell temperature is too high. When the second temperature information exceeds the second high temperature threshold, it indicates that the temperature is difficult to be effectively cooled by immersion in coolant circulation. At this time, there is a high probability of thermal runaway, thus generating abnormal temperature information. When the first temperature information exceeds the first high temperature for a long time, there is also a high probability of thermal runaway, thus generating abnormal temperature information.

[0008] In one embodiment of the present invention, the main UPS power supply is further provided with an auxiliary UPS power supply in parallel. The auxiliary UPS power supply is connected to a second static transfer switch. The second static transfer switch is used to control the auxiliary UPS power supply to provide auxiliary power to critical loads when the main UPS power supply is under maintenance, or to disconnect it from the grid.

[0009] To achieve the above technical solution, regular inspection and maintenance are necessary to ensure the normal operation of the system. In order to ensure that critical loads can still receive uninterrupted power supply during the inspection and maintenance process, an auxiliary UPS power supply is configured to replace the main UPS power supply to supply power to critical loads during the inspection and maintenance process. The status is switched through a second static transfer switch, thereby ensuring uninterrupted power supply to critical loads.

[0010] In one embodiment of the present invention, the detection control unit is further configured to perform the following operations: Determine if we are currently in peak power hours; If so, control the first static transfer switch to disconnect the grid power supply terminal from the grid and control the energy storage battery pack to start supplying power through the BMS system; If not, control the first static transfer switch to connect the grid power supply terminal to the grid and control the energy storage battery pack to stop supplying power or charge the energy storage battery pack through the BMS system.

[0011] The above technical solution enables the switching of power supply between the grid and the energy storage battery pack during peak and valley periods.

[0012] In one embodiment of the present invention, the detection control unit is further configured to perform the following operations: When the peak power period is reached, the SOC value of the energy storage battery pack is actively acquired. If the SOC value is less than the discharge threshold, the first static transfer switch is controlled to maintain the current state so that the power supply terminal of the grid remains connected to the grid. When the SOC value is detected to exceed the discharge threshold, the first static transfer switch is controlled to disconnect the power supply terminal from the grid and the energy storage battery pack is started to supply power through the BMS system.

[0013] To achieve the above technical solution, if the energy storage battery pack is not fully charged during off-peak hours and the SOC value is less than the discharge threshold, in order to prevent the energy storage battery pack from frequently charging and discharging and switching power supply in a short period of time, the grid-connected power supply is maintained at this time. When the SOC value exceeds the discharge threshold, the power is switched to the energy storage battery pack, thereby achieving the most cost-effective power supply.

[0014] In one embodiment of the present invention, the detection control unit is further configured to perform the following operations: When there is a second time remaining before the peak power period, the SOC value of the energy storage battery pack is actively acquired. If the SOC value is not 100%, the energy storage battery pack is charged by connecting to the mains power through the BMS system.

[0015] In one embodiment of the present invention, the second duration is determined based on the charging power and storage capacity of the energy storage battery pack, and at least satisfies the following: the second duration of continuous charging of the energy storage battery pack at the rated charging power can at least enable the SOC value to reach the discharge threshold.

[0016] The above technical solution ensures that the energy storage battery pack has sufficient energy storage capacity during peak power periods.

[0017] In one embodiment of the present invention, the detection control unit is further connected to an alarm device, the alarm device being equipped with an alarm confirmation button and a maintenance completion button, and the detection control unit is further configured to perform the following operations: When the continuous operating time of the main UPS power supply reaches the maintenance time, the alarm device is controlled to issue the first alarm information. When the alarm confirmation button is clicked to confirm the start of maintenance, the second static transfer switch is controlled to activate the auxiliary UPS power supply to provide auxiliary power to the critical load. When the maintenance completion button is clicked to confirm the completion of maintenance, the second static transfer switch is activated to disconnect the auxiliary UPS power supply from the grid and allow the main UPS power supply to connect to the grid.

[0018] To achieve the above technical solution, the maintenance duration is configured, and the alarm device provides timed reminders to ensure timely maintenance. When the maintenance personnel click the alarm confirmation button to confirm maintenance, the second static transfer switch activates the auxiliary UPS power supply to provide auxiliary power, ensuring uninterrupted power supply to critical loads during maintenance. After the maintenance personnel click the maintenance completion button to confirm completion, the second static transfer switch activates again to disconnect the auxiliary UPS power supply from the grid, restoring the main UPS power supply.

[0019] In one embodiment of the present invention, the detection control unit is further configured to perform the following operations: When the abnormal temperature information and the power grid fault information are received, the alarm device is controlled to issue a second alarm message.

[0020] The above technical solutions are implemented to enable timely notifications for maintenance of energy storage systems and power grids.

[0021] In one embodiment of the present invention, the first power supply circuit includes a plurality of power supply branches connected in parallel, and each power supply branch is connected to a circuit breaker.

[0022] The above technical solution can be implemented to meet the power demand of different general loads.

[0023] As described above, the present invention has the following beneficial effects: This invention provides an energy storage device with immersion liquid cooling. Typically, during peak electricity hours, the energy storage battery bank provides power, while during off-peak hours, the grid provides power and charges the battery bank, thus saving electricity costs. When the battery bank is supplying power, a high-voltage switchgear handles the access and distribution of power, which is then converted and regulated by an energy storage converter to supply power to the load. The device is managed and controlled by a BMS system. When power is supplied from the grid, the BMS system controls the battery bank to shut down or charge, directly supplying power to the general load in the first power supply circuit. Power is supplied through the second power supply circuit and then processed by the UPS power supply to supply power to critical loads. When grid switching is required due to peak-valley shifts, grid faults, insufficient power of the energy storage battery pack, or thermal runaway of the energy storage system, the first static transfer switch switches the state to achieve grid-connected or off-grid power supply at the grid power supply end. The BMS system controls the energy storage battery pack to supply power or disconnect it from the grid. Because the first static transfer switch can achieve fast power switching, general loads can achieve seamless switching at the millisecond level. On the second power supply circuit, due to the role of the UPS power supply, uninterrupted power supply to critical loads can be guaranteed. Attached Figure Description

[0024] Figure 1 The diagram shown is a system structure diagram of an energy storage device with immersion liquid cooling function according to Embodiment 1 of the present invention.

[0025] Figure 2 The diagram shown is a circuit schematic of an energy storage device with immersion liquid cooling function according to Embodiment 1 of the present invention.

[0026] Figure 3 The diagram shown is a system structure diagram of an energy storage device with immersion liquid cooling function in Embodiment 2 of the present invention.

[0027] Figure 4 The diagram shown is a circuit schematic of an energy storage device with immersion liquid cooling function according to Embodiment 2 of the present invention.

[0028] Component designation explanation 11. Energy storage battery pack; 12. High voltage box; 13. Energy storage converter; 14. BMS system; 20. Grid power supply terminal; 21. Point of common coupling; 22. Current transformer; 23. First static transfer switch; 30. First power supply circuit; 31. Power supply branch; 40. Second power supply circuit; 41. Main UPS power supply; 42. Auxiliary UPS power supply; 43. Second static transfer switch; 50. Detection and control unit; 60. Alarm device; 61. Alarm confirmation button; 62. Maintenance completion button. Detailed Implementation

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Example 1

[0030] Please see Figure 1 and Figure 2 This invention provides an energy storage device with immersion liquid cooling function, including an energy storage battery pack 11, a high-voltage box 12, an energy storage converter 13, and a BMS system 14 connected in sequence. The BMS system 14 is used to monitor the SOC value and temperature anomaly information of the energy storage battery pack 11. The energy storage converter 13 is connected to the grid power supply terminal 20 and forms a common connection point 21. The grid power supply terminal 20 is used to connect to the grid for power supply. The grid power supply terminal 20 is connected to a current transformer 22 for detecting grid fault information. The grid power supply terminal 20 is also connected to a first static transfer switch 23 for controlling the grid power supply terminal 20 and the energy storage converter 13 to be connected to the grid for power supply or disconnected from the grid. The common connection point 21 is connected to a first power supply circuit 30 for supplying power to general loads and a second power supply circuit 40 for supplying power to critical loads. The second power supply circuit 40 is connected to a main UPS power supply 41 for supplying power to critical loads.

[0031] Among them, a detection and control unit 50 is connected between the energy storage converter 13 and the grid power supply terminal 20. The detection and control unit 50 is connected to the BMS system 14 and the current transformer 22. The detection and control unit 50 is configured as follows: During the power supply process of the energy storage battery pack 11, if the SOC value is detected to be less than the low capacity warning threshold or the temperature abnormality information continues to be generated for more than the high temperature warning duration, the first static transfer switch 23 is controlled to activate the grid power supply terminal 20 to supply power, and the energy storage battery pack 11 is controlled to stop supplying power through the BMS system 14. If fault information detected by the current transformer 22 is collected during the power supply process at the power grid supply terminal 20, the first static transfer switch 23 is controlled to disconnect the power grid supply terminal 20 from the grid, and the energy storage battery pack 11 is controlled to start power supply through the BMS system 14.

[0032] Specifically, the energy storage battery pack 11 includes multiple single cells connected in series, and the energy storage battery pack 11 can also be connected to a power generation unit for power generation and energy storage, such as a photovoltaic power generation unit, a wind power generation unit, etc. The high-voltage box 12 can serve as an electrical connection and protection hub between the energy storage system and the external power grid and high-voltage load, such as for power access and distribution, distributing high-voltage power to devices such as the energy storage converter 13 within the system, and performing system protection and isolation, etc. The BMS system 14 (Battery Management System) is an electronic system used to monitor and manage the battery pack to ensure the safe and efficient operation of the battery. It can monitor parameters such as battery voltage, current, and temperature in real time. The energy storage battery pack 11, high-voltage box 12, energy storage converter 13, and BMS system 14 can all adopt existing structures and connection methods, which will not be elaborated here.

[0033] The low capacity warning threshold can usually be set to 10%-20%, preferably 10%. The high temperature warning duration can be set according to the characteristics of the battery. The first static transfer switch 23 is an STS switch, which is a fast and automatic power switching device based on semiconductor power devices.

[0034] In this embodiment, the energy storage battery pack 11 adopts an immersion liquid cooling circulation subsystem. The immersion liquid cooling circulation subsystem completely immerses the battery cells or modules in the insulating coolant. It achieves efficient heat dissipation through direct contact with the liquid and is an active thermal management system. Its immersion coolant (insulating liquid working fluid) is in direct contact with the battery surface. Through forced circulation of the liquid, the heat generated by the battery is carried away and transferred to the external secondary cooling system, which greatly reduces the temperature difference between the cells and can achieve rapid cooling, so that the battery always works in the optimal temperature window.

[0035] The BMS system 14 is used to collect the first temperature information of each individual cell in the energy storage battery pack 11 and the second temperature information of the immersed coolant. The BMS system 14 is configured to generate temperature anomaly information when the first temperature information exceeds a first high temperature threshold and the second temperature information exceeds a second high temperature threshold, or when the first temperature information exceeds the first high temperature threshold and the duration exceeds a first duration. Typically, the first high temperature threshold and the second high temperature threshold are set according to the battery characteristics and the physical properties of the immersed coolant. For example, the first high temperature threshold can be set to 55-60℃, and the second high temperature threshold can be set to 40-45℃, etc.

[0036] When the first temperature information exceeds the first high temperature threshold, it indicates that the cell temperature is too high. When the second temperature information exceeds the second high temperature threshold, it indicates that the temperature is difficult to be effectively cooled by immersion in coolant circulation. At this time, there is a high probability of thermal runaway, thus generating abnormal temperature information. When the first temperature information exceeds the first high temperature for a long time, there is also a high probability of thermal runaway, thus generating abnormal temperature information.

[0037] The detection control unit 50 is also used to perform the following operations: To determine whether it is currently in a peak power period, the peak power period can be set according to the specific electricity consumption rules of the region. It is understood that during peak power periods, the energy storage battery pack 11 will be used to supply power first, while during off-peak power periods, the grid power supply will be used first. If so, control the first static transfer switch 23 to disconnect the grid power supply terminal 20 from the grid and control the energy storage battery pack 11 to start power supply through the BMS system 14; If not, the first static transfer switch 23 is activated to connect the grid power supply terminal 20 to the grid, and the BMS system 14 controls the energy storage battery pack 11 to stop supplying power or to charge the energy storage battery pack 11. The charging of the energy storage battery pack 11 can be carried out by the grid or by the configured power generation unit. This enables the switching of power supply between the grid power supply terminal 20 and the energy storage battery pack 11 during peak and valley periods.

[0038] Furthermore, the detection control unit 50 is also used to perform the following operations: When peak power is reached, the SOC value of the energy storage battery pack 11 is actively acquired. If the SOC value is less than the discharge threshold, the first static transfer switch 23 is controlled to maintain the current state so that the grid power supply terminal 20 remains connected to the grid. When the SOC value is detected to exceed the discharge threshold, the first static transfer switch 23 is controlled to disconnect the grid power supply terminal 20 from the grid and the energy storage battery pack 11 is controlled to start power supply through the BMS system 14. The discharge threshold can be set to 50%-60% for example.

[0039] If the energy storage battery pack 11 is not fully charged during off-peak hours and the SOC value is less than the discharge threshold, in order to prevent the energy storage battery pack 11 from being frequently charged and discharged and to switch power supply in a short time, the grid power supply terminal 20 is still connected to the grid. When the SOC value exceeds the discharge threshold, the power supply is switched to the energy storage battery pack 11, thereby achieving the most cost-effective power supply.

[0040] Furthermore, the detection control unit 50 is also used to perform the following operations: When there is a second remaining time before the peak power period, the SOC value of the energy storage battery pack 11 is actively acquired. If the SOC value is not 100%, the BMS system 14 connects to the mains power to charge the energy storage battery pack 11. The second duration is determined based on the charging power and storage capacity of the energy storage battery pack 11, and at least satisfies the following: continuously charging the energy storage battery pack 11 at the rated charging power for the second duration can at least bring the SOC value to the discharge threshold. It is understood that the preferred second duration is the time required to charge the energy storage battery pack 11 from the low capacity warning threshold to 100%, thereby ensuring that the energy storage battery pack 11 has sufficient storage capacity when the peak power period arrives.

[0041] In this embodiment, the first power supply circuit 30 includes several power supply branches 31 connected in parallel, and each power supply branch 31 is connected to a circuit breaker, such as... Figure 2 Four power supply branches 31 are schematically shown, each equipped with a circuit breaker QF11 to QF14 to meet the power needs of different general loads. Circuit breakers 1QF and 2QF are also typically installed at the mains power supply end 20 for effective circuit protection. In some embodiments, the mains power supply end 20 is also connected to a Schneider surge protection device (SPD) and an external surge protector circuit breaker (SCB).

[0042] Normally, during peak power hours, the energy storage battery pack 11 provides power, while during off-peak hours, the grid provides power and charges the energy storage battery pack 11, thereby saving electricity costs. When the energy storage battery pack 11 is supplying power, the high-voltage switchgear handles the access and distribution of power, and the energy storage converter 13 performs conversion and regulation to supply power to the load. The BMS system 14 manages and controls this process. When the grid power supply terminal 20 is supplying power, the BMS system 14 controls the energy storage battery pack 11 to shut down or charge. In the first power supply circuit 30, power is directly supplied to general loads, while in the second power supply circuit... After being processed by the UPS power supply, the 40 supplies power to the critical load. When peak-valley shifts, grid faults, insufficient power of the energy storage battery pack 11, or thermal runaway of the energy storage system require grid-connected switching, the first static transfer switch 23 switches the state to realize grid-connected or off-grid power supply to the grid power supply terminal 20. The BMS system 14 controls the energy storage battery pack 11 to be powered or disconnected from the grid. Since the first static transfer switch 23 can realize fast power switching, general loads can achieve seamless switching at the millisecond level. On the second power supply circuit 40, due to the role of the UPS power supply, uninterrupted power supply to the critical load can be guaranteed. Example 2

[0043] The difference between this embodiment and Embodiment 1 is that in this embodiment, as... Figure 3 and Figure 4 As shown, the main UPS power supply 41 is also equipped with an auxiliary UPS power supply 42 in parallel. The auxiliary UPS power supply 42 is connected to a second static transfer switch 43. The second static transfer switch 43 is used to control the auxiliary UPS power supply 42 to provide auxiliary power to critical loads or to go offline when the main UPS power supply 41 is under maintenance. The second static transfer switch 43 is also an STS switch.

[0044] Regular maintenance is necessary to ensure the normal operation of the system. In order to ensure that critical loads can still receive uninterrupted power during maintenance, an auxiliary UPS power supply 42 is configured to replace the main UPS power supply 41 to supply power to critical loads during maintenance. The status is switched by the second static transfer switch 43, thereby ensuring uninterrupted power supply to critical loads.

[0045] In this embodiment, the detection control unit 50 is also connected to an alarm device 60, which is equipped with an alarm confirmation button 61 and a maintenance completion button 62. The detection control unit 50 is also used to perform the following operations: When the continuous operating time of the main UPS power supply 41 reaches the maintenance time, the control alarm device 60 issues the first alarm message. When the alarm confirmation button 61 is clicked to confirm the start of maintenance, the second static transfer switch 43 is activated to enable the auxiliary UPS power supply 42 to connect to the grid and provide auxiliary power to the critical load. When the maintenance completion button 62 is clicked to confirm the completion of maintenance, the second static transfer switch 43 is activated to disconnect the auxiliary UPS power supply 42 from the grid and allow the main UPS power supply 41 to connect to the grid for power supply.

[0046] By configuring the maintenance duration, the alarm device 60 provides timed reminders to facilitate timely maintenance. When the maintenance personnel click the alarm confirmation button 61 to confirm the maintenance, the second static transfer switch 43 activates the auxiliary UPS power supply 42 to provide auxiliary power, ensuring uninterrupted power supply to critical loads during the maintenance process. After clicking the maintenance completion button 62 to confirm the completion of the maintenance, the second static transfer switch 43 activates again to disconnect the auxiliary UPS power supply 42 from the grid, restoring power supply from the main UPS power supply 41.

[0047] Furthermore, the detection control unit 50 is also used to perform the following operations: when receiving abnormal temperature information and grid fault information, the control alarm device 60 issues a second alarm message; so as to promptly prompt maintenance of the energy storage system and the grid.

[0048] The above embodiments merely illustrate several implementation methods of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be noted that, for those skilled in the art, several modifications and improvements can be made without departing from the concept of the present invention. These are all equivalent modifications and improvements made to the above embodiments based on the essential technology of the present invention, and all of these fall within the protection scope of the present invention.

Claims

1. An energy storage device with immersion liquid cooling function, characterized in that, It includes an energy storage battery pack, a high-voltage box, an energy storage converter, and a BMS system connected in sequence. The BMS system is used to monitor the SOC value and temperature anomaly information of the energy storage battery pack. The energy storage converter is connected to the power grid supply end and forms a common connection point. The power grid supply end is used to connect to the power grid for power supply. The power grid supply end is connected to a current transformer for detecting fault information of the power grid. The power grid supply end is also connected to a first static transfer switch for controlling the power grid supply end to be connected to the power grid or disconnected from the power grid. The common connection point is connected to a first power supply circuit that supplies power to general loads and a second power supply circuit that supplies power to critical loads. The second power supply circuit is connected to the main UPS power supply for supplying power to critical loads. A detection and control unit is connected between the energy storage converter and the grid power supply terminal. The detection and control unit is connected to the BMS system and the current transformer. The detection and control unit is configured as follows: During the power supply process of the energy storage battery pack, if the SOC value is detected to be less than the low capacity warning threshold or the temperature abnormality information continues to be generated for more than the high temperature warning duration, the first static transfer switch is controlled to activate the grid power supply terminal to connect to the grid and the energy storage battery pack is controlled to stop supplying power through the BMS system. If fault information detected by the current transformer is collected during the power supply process at the grid power supply end, the first static transfer switch is controlled to disconnect the grid power supply end from the grid, and the energy storage battery pack is controlled to start power supply through the BMS system.

2. The energy storage device with immersion liquid cooling function according to claim 1, characterized in that, The energy storage battery pack adopts an immersion liquid cooling cycle subsystem, and the BMS system is used to collect the first temperature information of each single cell of the energy storage battery pack and the second temperature information of the immersion coolant. The BMS system is configured to generate the temperature anomaly information when the first temperature information exceeds a first high temperature threshold and the second temperature information exceeds a second high temperature threshold, or to generate the temperature anomaly information when the first temperature information exceeds the first high temperature threshold and the duration exceeds a first duration.

3. The energy storage device with immersion liquid cooling function according to claim 1, characterized in that, The main UPS power supply is also connected in parallel with an auxiliary UPS power supply. The auxiliary UPS power supply is connected to a second static transfer switch. The second static transfer switch is used to control the auxiliary UPS power supply to provide auxiliary power to critical loads when the main UPS power supply is under maintenance, or to disconnect it from the grid.

4. The energy storage device with immersion liquid cooling function according to claim 1, characterized in that, The detection control unit is also used to perform the following operations: Determine if we are currently in peak power hours; If so, control the first static transfer switch to disconnect the grid power supply terminal from the grid and control the energy storage battery pack to start supplying power through the BMS system; If not, control the first static transfer switch to connect the grid power supply terminal to the grid and control the energy storage battery pack to stop supplying power or charge the energy storage battery pack through the BMS system.

5. The energy storage device with immersion liquid cooling function according to claim 4, characterized in that, The detection control unit is also used to perform the following operations: When the peak power period is reached, the SOC value of the energy storage battery pack is actively acquired. If the SOC value is less than the discharge threshold, the first static transfer switch is controlled to maintain the current state so that the power supply terminal of the grid remains connected to the grid. When the SOC value is detected to exceed the discharge threshold, the first static transfer switch is controlled to disconnect the power supply terminal from the grid and the energy storage battery pack is started to supply power through the BMS system.

6. The energy storage device with immersion liquid cooling function according to claim 4 or 5, characterized in that, The detection control unit is also used to perform the following operations: When there is a second time remaining before the peak power period, the SOC value of the energy storage battery pack is actively acquired. If the SOC value is not 100%, the energy storage battery pack is charged by connecting to the mains power through the BMS system.

7. The energy storage device with immersion liquid cooling function according to claim 6, characterized in that, The second duration is determined based on the charging power and energy storage capacity of the energy storage battery pack, and at least satisfies the following: the second duration of continuous charging of the energy storage battery pack at the rated charging power is sufficient to make the SOC value reach the discharge threshold.

8. The energy storage device with immersion liquid cooling function according to claim 3, characterized in that, The detection and control unit is also connected to an alarm device, which is equipped with an alarm confirmation button and a maintenance completion button. The detection and control unit is also used to perform the following operations: When the continuous operating time of the main UPS power supply reaches the maintenance time, the alarm device is controlled to issue the first alarm information. When the alarm confirmation button is clicked to confirm the start of maintenance, the second static transfer switch is controlled to activate the auxiliary UPS power supply to provide auxiliary power to the critical load. When the maintenance completion button is clicked to confirm the completion of maintenance, the second static transfer switch is activated to disconnect the auxiliary UPS power supply from the grid and allow the main UPS power supply to connect to the grid.

9. The energy storage device with immersion liquid cooling function according to claim 8, characterized in that, The detection control unit is also used to perform the following operations: When the abnormal temperature information and the power grid fault information are received, the alarm device is controlled to issue a second alarm message.

10. The energy storage device with immersion liquid cooling function according to claim 1, characterized in that, The first power supply circuit includes several power supply branches connected in parallel, and each power supply branch is connected to a circuit breaker.

Images