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CN-122025907-A - Energy storage system and control method thereof

CN122025907ACN 122025907 ACN122025907 ACN 122025907ACN-122025907-A

Abstract

An energy storage system and a control method thereof are provided, wherein the energy storage system comprises a battery, an energy storage converter and a thermal management system, the thermal management system comprises a first heat exchange flow path comprising a first pump and a first heat exchanger used for carrying out heat exchange with the battery and configured to form a first heat exchange loop when the first pump is started, a second heat exchange flow path comprising a second pump and a second heat exchanger used for carrying out heat exchange with the energy storage converter and configured to form a second heat exchange loop when the second pump is started, a flow path switching mechanism, the first heat exchange flow path and the second heat exchange flow path are in operable communication through the flow path switching mechanism, and a processor is configured to carry out opening and closing control on the first pump and the second pump according to ambient temperature and carry out switching control on the flow path switching mechanism so as to switch the working mode of the thermal management system.

Inventors

  • HUANG YANCONG
  • XING YANQING
  • LI HUAJIE

Assignees

  • 宁德时代新能源科技股份有限公司

Dates

Publication Date
20260512
Application Date
20241112

Claims (20)

  1. 1. An energy storage system comprising a battery (10), an energy storage converter (20) and a thermal management system (30), wherein the thermal management system (30) comprises: A first heat exchange flow path (31) including a first pump (311) and a first heat exchanger (312) for heat exchange with the battery (10), and configured to form a first heat exchange circuit when the first pump (311) is turned on; a second heat exchange flow path (32) comprising a second pump (321) and a second heat exchanger (322) for heat exchange with the energy storage converter (20), and configured to form a second heat exchange circuit when the second pump (321) is turned on; A flow path switching mechanism (34), the first heat exchange flow path (31) and the second heat exchange flow path (32) being in operable communication by the flow path switching mechanism (34), and And a processor (35) configured to control opening and closing of the first pump (311) and the second pump (321) according to an ambient temperature, and to control switching of the flow path switching mechanism (34) so as to switch an operation mode of the thermal management system (30).
  2. 2. The energy storage system of claim 1, wherein the processor (35) is configured to: Responsive to the thermal management system (30) switching to a first mode of operation, operating the first heat exchange circuit and the second heat exchange circuit independently; in response to the thermal management system (30) switching to a second mode of operation, at least a portion of the first and second heat exchange flow paths (32) are formed into a single pump driven heat exchange combined loop.
  3. 3. The energy storage system according to claim 2, wherein the flow path switching mechanism (34) includes: At least two communication flow paths (33), both ends of each communication flow path (33) being respectively communicated with the first heat exchange flow path (31) and the second heat exchange flow path (32), and A control valve (341) provided in at least one of the at least two communication channels (33) and configured to switch on/off of a communication channel (33) in which the control valve (341) is provided in the at least two communication channels (33); Wherein the processor (35) is configured to: -in response to the ambient temperature being greater than a first ambient temperature threshold T th1 , causing both the first pump (311) and the second pump (321) to be turned on and the control valve (341) to be switched to an off state to switch the thermal management system (30) to the first mode of operation; Responsive to the ambient temperature being less than or equal to a second ambient temperature threshold T th2 , the first pump (311) is turned on, the second pump (321) is turned off, and the control valve (341) is switched to an on state to switch the thermal management system (30) to the second mode of operation, wherein the first ambient temperature threshold T th1 is greater than the second ambient temperature threshold T th2 .
  4. 4. The energy storage system of claim 3, wherein the first ambient temperature threshold T th1 , the second ambient temperature threshold T th2 satisfy: T th1 ＝T batt -A,T th2 ＝T batt -B,T th1 >T th2 ; Wherein T batt is the heat exchange medium temperature capable of maintaining the temperature of the battery (10) in the working interval in the first heat exchanger (312), A, B is a preset constant value, and the temperature is 3 ℃ less than or equal to A <5 ℃, and 3 ℃ less than or equal to B <5 ℃.
  5. 5. The energy storage system of any of claims 2-4, wherein the thermal management system (30) further comprises a compression refrigeration cycle (36), the compression refrigeration cycle (36) comprising a compressor (361) and an evaporator (364), a portion of the first heat exchange flow path (31) passing through the evaporator (364) and exchanging heat with the compression refrigeration cycle (36) through the evaporator (364); Wherein the processor (35) is configured to: -operating the compressor (361) at a first operating frequency in response to the thermal management system (30) switching to the first operating mode; -in response to the thermal management system (30) switching to the second mode of operation, causing the compressor (361) to shut down or operate at a second operating frequency, wherein the second operating frequency is less than the first operating frequency.
  6. 6. The energy storage system according to any one of claims 2-5, wherein the flow path switching mechanism (34) comprises at least two communication flow paths (33), both ends of each communication flow path (33) are respectively communicated with the first heat exchange flow path (31) and the second heat exchange flow path (32), the thermal management system (30) further comprises a heating mechanism (371), the heating mechanism (371) is arranged in at least one of the at least two communication flow paths (33) and is configured to heat a heat exchange medium flowing through the communication flow path (33) in which the heating mechanism (371) is arranged when a heating function is started; Wherein the processor (35) is configured to: -responsive to the thermal management system (30) switching to the first mode of operation, causing the heating mechanism (371) to switch off a heating function; Responsive to the thermal management system (30) switching to the second mode of operation, the heating mechanism (371) is caused to turn on or off a heating function.
  7. 7. The energy storage system of any of claims 2-6, wherein the processor (35) is configured to: In response to the thermal management system (30) switching to the first mode of operation, the output flow of the first pump (311) is controlled according to a temperature difference Δt 1 between an outlet temperature T out1 and an inlet temperature T in1 of the first heat exchanger (312) in the first heat exchange loop.
  8. 8. The energy storage system of claim 7, wherein the processor (35) is configured to: Responsive to the temperature difference ΔT 1 being greater than a first temperature difference threshold ΔT th1 , increasing a rotational speed of the first pump (311) to increase an output flow of the first pump (311); Reducing the rotational speed of the first pump (311) to reduce the output flow of the first pump (311) in response to the temperature difference DeltaT 1 being less than a second temperature difference threshold DeltaT th2 , and/or In response to the temperature difference ΔT 1 being greater than or equal to the second temperature difference threshold ΔT th2 and less than or equal to the first temperature difference threshold ΔT th1 , maintaining the rotational speed of the first pump (311) unchanged; Wherein the first temperature difference threshold ΔT th1 is greater than the second temperature difference threshold ΔT th2 .
  9. 9. The energy storage system of claim 8, wherein, The first temperature difference threshold value delta T th1 is less than or equal to 3.5 ℃ and less than or equal to delta T th1 and less than or equal to 4.5 ℃; The second temperature difference threshold value delta T th2 is less than or equal to 1 ℃ and less than or equal to delta T th2 and less than or equal to 2.5 ℃.
  10. 10. The energy storage system of any of claims 2-9, wherein the second heat exchange flow path (32) further comprises a natural cooling heat exchanger (325) in series with the second heat exchanger (322), the processor (35) configured to: In response to the thermal management system (30) switching to the first mode of operation, the output flow of the second pump (321) is controlled according to a temperature difference ΔT 2 between an outlet temperature T out2 and an inlet temperature T in2 of a series flow path of the second heat exchanger (322) and the free cooling heat exchanger (325) in the second heat exchange loop, and a pressure difference ΔP between an inlet pressure P in2 of the second pump (321) and an inlet pressure P in1 of the first pump (311).
  11. 11. The energy storage system of claim 10, wherein the processor (35) is configured to: Responsive to the temperature difference ΔT 2 being greater than a third temperature difference threshold ΔT th3 and the pressure difference ΔP being less than or equal to a pressure threshold ΔP th , increasing the rotational speed of the second pump (321) to increase the output flow of the second pump (321); reducing the rotational speed of the second pump (321) to reduce the output flow of the second pump (321) in response to the temperature difference DeltaT 2 being less than a fourth temperature difference threshold DeltaT th4 , and/or In response to the temperature difference ΔT 2 being greater than or equal to the fourth temperature difference threshold ΔT th4 and less than or equal to the third temperature difference threshold ΔT th3 , maintaining the rotational speed of the second pump (321) unchanged; Wherein the third temperature difference threshold ΔT th3 is greater than the fourth temperature difference threshold ΔT th4 .
  12. 12. The energy storage system of claim 11, wherein, The third temperature difference threshold value delta T th3 is more than or equal to 6 ℃ and less than or equal to delta T th3 and less than or equal to 7 ℃; The fourth temperature difference threshold value delta T th4 is equal to or less than 4 ℃ and equal to or less than th4 and is equal to or less than 5 ℃; the pressure threshold value delta P th is more than or equal to 25KPa and less than or equal to delta P th and less than or equal to 45KPa.
  13. 13. The energy storage system of any of claims 2-6, wherein the second heat exchange flow path (32) further comprises a natural cooling heat exchanger (325) in series with the second heat exchanger (322), the flow path switching mechanism (34) comprising: At least two communication flow paths (33), both ends of each communication flow path (33) being respectively communicated with the first heat exchange flow path (31) and the second heat exchange flow path (32), and A control valve (341) provided in at least one of the at least two communication channels (33) and configured to switch on/off of a communication channel (33) in which the control valve (341) is provided in the at least two communication channels (33); The processor (35) is configured to: In response to the thermal management system (30) switching to the second mode of operation, controlling flow into the second heat exchange flow path (32) in the heat exchange combining loop according to an outlet temperature T out2 of a series flow path section of the second heat exchanger (322) and the natural cooling heat exchanger (325) in the second heat exchange flow path (32).
  14. 14. The energy storage system of claim 13, wherein the processor (35) is configured to: In response to the outlet temperature T out2 being less than a first target temperature threshold T th3 , increasing the opening of the control valve (341) to increase the flow into the second heat exchange flow path (32) in the heat exchange combining loop; Responsive to the outlet temperature T out2 being greater than a second target temperature threshold T th4 , decreasing the opening of the control valve (341) to reduce the flow into the second heat exchange flow path (32) in the heat exchange combining circuit, and/or In response to the outlet temperature T out2 being equal to or less than the first target temperature threshold T th3 and equal to or greater than the second target temperature threshold T th4 , maintaining the flow into the second heat exchange flow path (32) in the heat exchange combined circuit unchanged; Wherein the second target temperature threshold T th4 is greater than the first target temperature threshold T th3 .
  15. 15. The energy storage system of claim 14, wherein, The first target temperature threshold T th3 is 15 ℃ or less and T th3 or less and 17 ℃; The second target temperature threshold T th4 satisfies that T th4 is less than or equal to 19 ℃ and less than or equal to 21 ℃.
  16. 16. The energy storage system of claim 14 or 15, wherein the processor (35) is configured to: In response to the thermal management system (30) switching to the second mode of operation, the output flow of the first pump (311) is controlled according to a temperature difference Δt 1 between an outlet temperature T out1 and an inlet temperature T in1 of the first heat exchanger (312) in the first heat exchange loop.
  17. 17. The energy storage system of claim 16, wherein the processor (35) is configured to: Responsive to the temperature difference ΔT 1 being greater than a first temperature difference threshold ΔT th1 , increasing a rotational speed of the first pump (311) to increase an output flow of the first pump (311); Reducing the rotational speed of the first pump (311) to reduce the output flow of the first pump (311) in response to the temperature difference DeltaT 1 being less than a second temperature difference threshold DeltaT th2 , and/or In response to the temperature difference ΔT 1 being greater than or equal to the second temperature difference threshold ΔT th2 and less than or equal to the first temperature difference threshold ΔT th1 , maintaining the rotational speed of the first pump (311) unchanged; Wherein the first temperature difference threshold ΔT th1 is greater than the second temperature difference threshold ΔT th2 .
  18. 18. The energy storage system of claim 17, wherein, The first temperature difference threshold value delta T th1 is less than or equal to 3.5 ℃ and less than or equal to delta T th1 and less than or equal to 4.5 ℃; The second temperature difference threshold value delta T th2 is less than or equal to 1 ℃ and less than or equal to delta T th2 and less than or equal to 2.5 ℃.
  19. 19. A control method of an energy storage system according to any one of claims 1-18, the flow path switching mechanism (34) comprising at least two communication flow paths (33) and a control valve (341), both ends of each communication flow path (33) being respectively communicated with the first heat exchange flow path (31) and the second heat exchange flow path (32), the control valve (341) being provided in at least one of the at least two communication flow paths (33) and configured to switch on and off of a communication flow path (33) in which the control valve (341) is provided in the at least two communication flow paths (33); The control method comprises the following steps: Responsive to the ambient temperature being greater than a first ambient temperature threshold T th1 , causing both the first pump (311) and the second pump (321) to be turned on and the control valve (341) to be switched to an off state to switch the thermal management system (30) to a first mode of operation to cause the first heat exchange circuit and the second heat exchange circuit to operate independently; In response to the ambient temperature being less than or equal to a second ambient temperature threshold T th2 , the first pump (311) is turned on, the second pump (321) is turned off, and the control valve (341) is switched to an on state to switch the thermal management system (30) to a second operating mode such that at least portions of the first and second heat exchange circuits (32) form a single pump driven heat exchange combined circuit, wherein the first ambient temperature threshold T th1 is greater than the second ambient temperature threshold T th2 .
  20. 20. The control method of claim 19, wherein the first ambient temperature threshold T th1 , the second ambient temperature threshold T th2 satisfy: T th1 ＝T batt -A,T th2 ＝T batt -B,T th1 >T th2 ; Wherein T batt is the heat exchange medium temperature capable of maintaining the temperature of the battery (10) in the working interval in the first heat exchanger (312), A, B is a preset constant value, and the temperature is 3 ℃ less than or equal to A <5 ℃, and 3 ℃ less than or equal to B <5 ℃.

Description

Energy storage system and control method thereof Technical Field The invention relates to the technical field of energy storage, in particular to an energy storage system and a control method thereof. Background With the increasing increase of environmental pollution, the new energy industry is receiving more and more attention. In the new energy industry, battery technology is an important factor in its development. The rechargeable battery can activate the active substance to continue to use in a charging mode after discharging, and has wide application prospect in the field of large-scale energy storage. Disclosure of Invention In one aspect of the present disclosure, there is provided an energy storage system comprising a battery, an energy storage converter, and a thermal management system, wherein the thermal management system comprises: a first heat exchange flow path including a first pump and a first heat exchanger for heat exchange with the battery, and configured to form a first heat exchange circuit when the first pump is turned on; A second heat exchange flow path including a second pump and a second heat exchanger for heat exchange with the energy storage converter, and configured to form a second heat exchange circuit when the second pump is turned on; A flow path switching mechanism by which the first heat exchange flow path and the second heat exchange flow path are in operable communication, and And the processor is configured to control the opening and closing of the first pump and the second pump according to the ambient temperature and control the switching of the flow path switching mechanism so as to switch the working mode of the thermal management system. In this embodiment, the first heat exchanger in the first heat exchange flow path and the second heat exchanger in the second heat exchange flow path can exchange heat with the battery and the energy storage converter respectively, the first heat exchange flow path and the second heat exchange flow path are in operable communication through the flow path switching mechanism, and the processor can send a control instruction to the first pump in the first heat exchange flow path, the second pump in the second heat exchange flow path and the flow path switching mechanism according to the ambient temperature, so as to realize the opening and closing control of the first pump and the second pump and the switching control of the flow path switching mechanism, so as to switch the working mode of the thermal management system, thereby enabling the working mode of the thermal management system to be adapted to the ambient temperature, and being beneficial to improving the energy efficiency and the flexibility of the system. In some embodiments, the processor is configured to: responsive to the thermal management system switching to a first mode of operation, operating the first heat exchange circuit and the second heat exchange circuit independently; And in response to the thermal management system switching to a second mode of operation, causing at least a portion of the first and second heat exchange circuits to form a single pump driven heat exchange combined circuit. In this embodiment, when the thermal management system is switched to the first working mode, the first heat exchange flow path and the second heat exchange flow path respectively form a first heat exchange loop and the second heat exchange loop independently operate, so that the first heat exchange flow path and the second heat exchange flow path can be independently configured and controlled according to the thermal management requirements of the battery and the energy storage converter, and the more flexible thermal management requirements are satisfied. In some embodiments, the flow path switching mechanism includes: At least two communication flow paths, two ends of each communication flow path being respectively communicated with the first heat exchange flow path and the second heat exchange flow path, and A control valve provided in at least one of the at least two communication channels, configured to switch on/off of a communication channel in which the control valve is provided among the at least two communication channels; wherein the processor is configured to: Responsive to the ambient temperature being greater than or equal to a first ambient temperature threshold T th1, causing both the first pump and the second pump to be on and causing the control valve to switch to an off state to switch the thermal management system to the first mode of operation; In response to the ambient temperature being less than or equal to a second ambient temperature threshold T th2, the first pump is turned on, the second pump is turned off, and the control valve is switched to an on state to switch the thermal management system to the second mode of operation, wherein the first ambient temperature threshold T th1 is greater than the second ambient temperature threshold T th2. In