Energy storage system and new energy system

Abstract

The application discloses an energy storage system and a new energy system. The energy storage system comprises a battery pack, an energy storage converter, a temperature control system and a control module. The temperature control system comprises a refrigerant circulation loop, a dry cooler, a first heat exchange branch for heat exchange with the battery pack, a second heat exchange branch for heat exchange with the energy storage converter, a third heat exchange branch for heat exchange with the refrigerant circulation loop through a plate heat exchanger, a fourth heat exchange branch for heat exchange with the dry cooler, a first switching device, a second switching device and a heater arranged in the third heat exchange branch. The control module is configured to control the working mode of the temperature control system according to the temperature and the charging and discharging state of the battery pack. The energy storage system can meet different heat exchange requirements of the battery pack and the energy storage converter, and the energy efficiency of the energy storage system is improved.

Description

Technical Field

[0001] This invention relates to the field of energy storage technology, and in particular to an energy storage system and a new energy system. Background Technology

[0002] With the continuous development of new energy sources, energy storage systems are widely used in various fields, such as photovoltaics and electric vehicles. Energy storage systems include battery packs and power conversion systems (PCS). As the energy density of energy storage systems continues to increase, and in order to improve the energy efficiency of these systems, thermal management requirements exist for both the battery packs and the power conversion systems.

[0003] However, current energy storage systems cannot meet the heat exchange requirements of battery packs and energy storage converters in various scenarios, resulting in low energy efficiency of energy storage systems. Summary of the Invention

[0004] The purpose of this invention is to at least solve one of the technical problems existing in the prior art, and to provide an energy storage system and a new energy system that can provide a variety of different heat exchange requirements for battery packs and energy storage converters, and improve the energy efficiency of the energy storage system.

[0005] In a first aspect, embodiments of the present invention provide an energy storage system, including a battery pack, an energy storage converter, a temperature control system, and a control module, wherein the energy storage converter is electrically connected to the battery pack, wherein:

[0006] The temperature control system includes a refrigerant circulation loop, a dry cooler, a first heat exchange branch that exchanges heat with the battery pack, a second heat exchange branch that exchanges heat with the energy storage converter, a third heat exchange branch that exchanges heat with the refrigerant circulation loop via a plate heat exchanger, a fourth heat exchange branch that exchanges heat with the dry cooler, a first switching device, a second switching device, and a heater installed in the third heat exchange branch. The first switching device is connected to the inlet of the first heat exchange branch, the inlet of the second heat exchange branch, the outlet of the third heat exchange branch, and the outlet of the fourth heat exchange branch. The second switching device is connected to the outlet of the first heat exchange branch, the outlet of the second heat exchange branch, the inlet of the third heat exchange branch, and the inlet of the fourth heat exchange branch.

[0007] The control module is configured as follows:

[0008] The operating mode of the temperature control system is controlled according to the temperature and charging / discharging state of the battery pack.

[0009] The energy storage system provided by the embodiments of the present invention has at least the following beneficial effects: When the refrigerant circulation loop in the temperature control system is operating, it can exchange heat with the refrigerant circulation loop through a plate heat exchanger; the fourth heat exchange branch where the dry cooler is located can exchange heat with the external environment through the dry cooler; a heater is also provided in the third heat exchange branch to heat the heat exchange medium flowing through the third heat exchange branch, enabling various different heat exchange methods. Based on this, the first switching device and the second switching device can control the first heat exchange branch where the battery pack is located and the second heat exchange branch where the energy storage converter is located, connecting them to the third heat exchange branch or the fourth heat exchange branch, thus providing various different heat exchange requirements for the battery pack and the energy storage converter. Furthermore, the control module controls the operating mode of the temperature control system according to the temperature and charging / discharging state of the battery pack, ensuring that the temperature of the battery pack is maintained within a suitable range under different conditions, which is beneficial to improving the energy efficiency of the energy storage system.

[0010] According to some embodiments of the energy storage system provided by the present invention, the temperature control system has a first operating mode. In the first operating mode, the control module controls the refrigerant circulation loop to operate, controls the first switching device to connect the outlet of the third heat exchange branch to the inlet of the first heat exchange branch and the inlet of the second heat exchange branch, and controls the second switching device to connect the outlet of the first heat exchange branch and the outlet of the second heat exchange branch to the inlet of the third heat exchange branch.

[0011] According to some embodiments of the energy storage system provided by the present invention, the temperature control system has a second operating mode. In the second operating mode, the control module controls the heater to operate, controls the first switching device to connect the outlet of the third heat exchange branch to the inlet of the first heat exchange branch and the inlet of the second heat exchange branch, and controls the second switching device to connect the outlet of the first heat exchange branch and the outlet of the second heat exchange branch to the inlet of the third heat exchange branch.

[0012] According to some embodiments of the energy storage system provided by the present invention, the temperature control system has a third operating mode. In the third operating mode, the control module controls the first switching device to connect the outlet of the fourth heat exchange branch to the inlet of the first heat exchange branch and the inlet of the second heat exchange branch, and controls the second switching device to connect the outlet of the first heat exchange branch and the outlet of the second heat exchange branch to the inlet of the fourth heat exchange branch.

[0013] According to some embodiments of the energy storage system provided by the present invention, controlling the operating mode of the temperature control system based on the temperature and charge / discharge state of the battery pack includes:

[0014] The temperature of the battery pack at multiple different measurement points is obtained, and the maximum and minimum battery temperatures are determined.

[0015] The operating mode of the temperature control system is controlled based on the maximum battery temperature, the minimum battery temperature, and the charging and discharging state of the battery pack.

[0016] According to some embodiments of the energy storage system provided by the present invention, when the battery pack is in a charging and discharging state and the maximum battery temperature is greater than a first preset value, the control module controls the temperature control system to enter the first working mode.

[0017] According to some embodiments of the energy storage system provided by the present invention, when the battery pack is in a charging and discharging state and the minimum battery temperature is less than a second preset value, the control module controls the temperature control system to enter the second working mode.

[0018] According to some embodiments of the present invention, when the battery pack is not in a charging or discharging state and the maximum battery temperature is greater than a third preset value, the control module controls the temperature control system to enter the first working mode, wherein the third preset value is greater than the first preset value.

[0019] According to some embodiments of the energy storage system provided by the present invention, when the battery pack is not in a charging or discharging state and the minimum battery temperature is less than a fourth preset value, the control module controls the temperature control system to enter the second working mode, wherein the fourth preset value is less than the second preset value.

[0020] According to some embodiments of the energy storage system provided by the present invention, when the battery pack is not in a charging or discharging state, and the difference between the maximum battery temperature and the minimum battery temperature is greater than a fifth preset value, the control module controls the temperature control system to enter the third working mode.

[0021] According to some embodiments of the energy storage system provided by the present invention, the first operating mode has a higher priority than the second operating mode.

[0022] According to some embodiments of the energy storage system provided by the present invention, the second operating mode has a higher priority than the third operating mode.

[0023] According to some embodiments of the present invention, the plate heat exchanger has a first heat exchange channel and a second heat exchange channel arranged to exchange heat with each other, the first heat exchange channel being connected to the refrigerant circulation loop, and the second heat exchange channel being connected to the third heat exchange branch.

[0024] According to some embodiments of the energy storage system provided by the present invention, the temperature control system further includes a dehumidification branch connected in parallel with the first heat exchange channel, the dehumidification branch being equipped with a dehumidifier, and the control module controlling the dehumidifier to operate in the first working mode.

[0025] The energy storage system provided according to some embodiments of the present invention further includes a high-voltage box, wherein in the first operating mode, the dehumidifier is used to cool and dehumidify the high-voltage box.

[0026] According to some embodiments of the energy storage system provided by the present invention, in the first operating mode, when the maximum battery temperature drops below a sixth preset value, the control module controls the temperature control system to switch from the first operating mode to a fourth operating mode; wherein, in the fourth operating mode, the control module controls the first switching device to connect the outlet of the fourth heat exchange branch to the inlet of the first heat exchange branch and the inlet of the second heat exchange branch, and controls the second switching device to connect the outlet of the first heat exchange branch and the outlet of the second heat exchange branch to the inlet of the fourth heat exchange branch.

[0027] According to some embodiments of the energy storage system provided by the present invention, in the first working mode, when the maximum battery temperature drops below a seventh preset value, and the difference between the maximum battery temperature and the minimum battery temperature is less than an eighth preset value, the control module controls the temperature control system to switch from the first working mode to the third working mode.

[0028] According to some embodiments of the energy storage system provided by the present invention, in the second operating mode, when the minimum battery temperature rises above a ninth preset value, and the difference between the maximum battery temperature and the minimum battery temperature is less than a tenth preset value, the control module controls the temperature control system to switch from the second operating mode to the third operating mode.

[0029] Secondly, embodiments of the present invention provide a new energy system, including the energy storage system described in the first aspect of the embodiments above.

[0030] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the description, claims, and drawings. Attached Figure Description

[0031] The accompanying drawings are provided to further understand the technical solutions of the present invention and constitute a part of the specification. They are used together with the embodiments of the present invention to explain the technical solutions of the present invention, and do not constitute a limitation on the technical solutions of the present invention.

[0032] The present invention will be further described below with reference to the accompanying drawings and embodiments;

[0033] Figure 1 This is an overall schematic diagram of the energy storage system provided in an embodiment of the present invention;

[0034] Figure 2 This is a schematic diagram of the specific structure of the temperature control system in the energy storage system provided in the embodiment of the present invention;

[0035] Figure 3 This is a schematic diagram of the flow direction of the heat exchange medium in the first working mode of the temperature control system in the energy storage system provided in the embodiment of the present invention;

[0036] Figure 4 This is a schematic diagram of the flow direction of the heat exchange medium in the second or third working mode of the temperature control system in the energy storage system provided in the embodiments of the present invention.

[0037] Figure 5 This is a schematic diagram of the flow direction of the heat exchange medium in the fourth working mode of the temperature control system in the energy storage system provided in the embodiment of the present invention;

[0038] Figure 6 This is a flowchart of the method executed by the control module in the energy storage system provided in this embodiment of the invention;

[0039] Figure 7 This is a flowchart of a method executed by the control module in an energy storage system provided in another embodiment of the present invention. Detailed Implementation

[0040] 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 a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0041] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0042] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0043] This invention provides an energy storage system and a new energy system that can meet various heat exchange requirements of battery packs and energy storage converters, and improve the energy efficiency of the energy storage system.

[0044] The embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0045] Figure 1 This is a schematic diagram of the energy storage system provided in an embodiment of the present invention. (Refer to...) Figure 1 The energy storage system includes a battery pack 100, an energy storage converter 200, a temperature control system 300, and a control module. The battery pack 100 stores electrical energy and releases it when needed. Multiple battery packs 100 can be configured, for example, as shown in the reference... Figure 1 The battery packs shown are 1, 2, ..., n; the energy storage converter 200 is electrically connected to the battery pack 100. The energy storage converter 200 is used to convert the DC power of the battery pack 100 into AC power. It can operate in grid-connected or off-grid mode. In grid-connected mode, the energy storage converter 200 interacts with the grid according to the dispatch instructions. In off-grid mode, it can provide voltage and frequency support for the load.

[0046] Figure 2 This is a schematic diagram of the specific structure of the temperature control system 300 in the energy storage system provided in this embodiment of the invention. (Refer to...) Figure 2The temperature control system 300 includes a refrigerant circulation loop 305, a dry cooler 310, a first heat exchange branch 301 that exchanges heat with the battery pack 100, a second heat exchange branch 302 that exchanges heat with the energy storage converter 200, a third heat exchange branch 303 that exchanges heat with the refrigerant circulation loop 305 via a plate heat exchanger 320, a fourth heat exchange branch 304 that exchanges heat with the dry cooler 310, a first switching device 330, a second switching device 340, and a heater 350 disposed in the third heat exchange branch 303. The first switching device 330 is connected to the inlet a1 of the first heat exchange branch 301, the inlet b1 of the second heat exchange branch 302, the outlet c2 of the third heat exchange branch 303, and the outlet d2 of the fourth heat exchange branch 304. The second switching device 340 is connected to the outlet a2 of the first heat exchange branch 301, the outlet b2 of the second heat exchange branch 302, the inlet c1 of the third heat exchange branch 303, and the inlet d1 of the fourth heat exchange branch 304, respectively. The plate heat exchanger 320 has a first heat exchange channel and a second heat exchange channel that are configured to exchange heat with each other. The first heat exchange channel is connected to the refrigerant circulation loop 305, and the second heat exchange channel is connected to the third heat exchange branch 303. In addition, the refrigerant circulation loop 305 includes a compressor 3051, a condenser 3052, and a first electronic expansion valve 3053 connected in sequence. The first heat exchange channel of the plate heat exchanger 320 is connected between the compressor 3051 and the first electronic expansion valve 3053.

[0047] It is understood that the battery pack 100 is used to store electrical energy and release the stored electrical energy when needed. Heat is generated during the storage and release of electrical energy in the battery pack 100, which can be understood as a heat-generating device in the energy storage system. The first heat exchange branch 301 is configured to exchange heat with the battery pack 100. The heat exchange between the first heat exchange branch 301 and the battery pack 100 can be achieved through thermally conductive bonding, or the battery pack 100 can be connected to the first heat exchange branch 301 through a heat exchange channel. The energy storage system uses the first heat exchange branch 301 to dissipate heat and cool down or heat up the battery pack 100. Specifically, in this embodiment, the first heat-conducting plate in the first heat exchange branch 301 is thermally conductively bonded to the battery pack 100. The heat exchange medium flows through the first heat-conducting plate and exchanges heat with the battery pack 100, allowing the battery pack 100 to operate under suitable temperature conditions and improving the reliability of the energy storage system.

[0048] The energy storage converter 200 controls the charging and discharging process of the battery pack 100, performing AC / DC conversion. The energy storage converter 200 also generates heat during operation; therefore, it can be understood as a heat-generating device in the energy storage system. Correspondingly, the second heat exchange branch 302 is configured to exchange heat with the energy storage converter 200. The heat exchange between the second heat exchange branch 302 and the energy storage converter 200 can be achieved through thermally conductive bonding, or the energy storage converter 200 can be connected to the second heat exchange branch 302 via a heat exchange channel. The energy storage system dissipates heat and cools the energy storage converter 200 through the second heat exchange branch 302. Specifically, in this embodiment, the second heat-conducting plate in the second heat exchange branch 302 is thermally conductively bonded to the energy storage converter 200. The heat exchange medium flows through the second heat-conducting plate and exchanges heat with the energy storage converter 200, allowing the energy storage converter 200 to operate under suitable temperature conditions and improving the reliability of the energy storage system.

[0049] The control module is configured to control the operating mode of the temperature control system 300 based on the temperature and charging / discharging status of the battery pack 100.

[0050] According to the energy storage system provided in the embodiment of the present invention, when the refrigerant circulation loop 305 in the temperature control system 300 is operating, it can exchange heat with the refrigerant circulation loop 305 through the plate heat exchanger 320. The fourth heat exchange branch 304 where the dry cooler 310 is located can exchange heat with the external environment through the dry cooler 310. The third heat exchange branch 303 is also provided with a heater 350 to heat the heat exchange medium flowing through the third heat exchange branch 303, which can realize a variety of different heat exchange methods. Based on this, the first switching device 330 and the second switching device 340... The control module can control the first heat exchange branch 301 where the battery pack 100 is located and the second heat exchange branch 302 where the energy storage converter 200 is located, and connect them to the third heat exchange branch 303 or the fourth heat exchange branch 304, so as to provide various heat exchange requirements for the battery pack 100 and the energy storage converter 200. In addition, the control module controls the working mode of the temperature control system 300 according to the temperature and charging and discharging state of the battery pack 100, so that the temperature of the battery pack 100 can be maintained within a suitable range under different conditions, which is conducive to improving the energy efficiency of the energy storage system.

[0051] In some embodiments, reference is made to Figure 2 As shown, the first switching device 330 includes a first three-way valve 331 and a first three-way connector 332. The three ports of the first three-way valve 331 are respectively connected to the inlet b1 of the second heat exchange branch 302, the outlet c2 of the third heat exchange branch 303, and one connector of the first three-way connector 332. The other two connectors of the first three-way connector 332 are respectively connected to the inlet a1 of the first heat exchange branch 301 and the outlet d2 of the fourth heat exchange branch 304.

[0052] It is understood that the first switching device 330 can also be implemented using other components, such as a four-way valve. The four ports of the four-way valve are respectively connected to the inlet a1 of the first heat exchange branch 301, the inlet b1 of the second heat exchange branch 302, the outlet c2 of the third heat exchange branch 303, and the outlet d2 of the fourth heat exchange branch 304. This application does not limit the specific structure of the first switching device 330. It can be composed of multiple valve bodies or a single multi-way valve, as long as the first switching device 330 can achieve the required connection relationship.

[0053] In some embodiments, reference is made to Figure 2 As shown, the second switching device 340 includes a second three-way valve 341. The outlet a2 of the first heat exchange branch 301 and the outlet b2 of the second heat exchange branch 302 converge and are then connected to one port of the second three-way valve 341 through a common pipe. The other two ports of the second three-way valve 341 are respectively connected to the inlet c1 of the third heat exchange branch 303 and the inlet d1 of the fourth heat exchange branch 304.

[0054] It is understood that the second switching device 340 can also be implemented using other components, such as a four-way valve. The four ports of the four-way valve are respectively connected to the outlet a2 of the first heat exchange branch 301, the outlet b2 of the second heat exchange branch 302, the inlet c1 of the third heat exchange branch 303, and the inlet d1 of the fourth heat exchange branch 304. This application does not limit the specific structure of the second switching device 340. It can be composed of multiple valve bodies or a single multi-way valve, as long as the second switching device 340 can achieve the required connection relationship.

[0055] Continue to refer to Figure 2 In some embodiments, the temperature control system 300 further includes a first pump body 3031 disposed in the third heat exchange branch 303. The first pump body 3031 may be disposed between the inlet c1 of the third heat exchange branch 303 and the plate heat exchanger 320. When the first pump body 3031 is working, it can drive the heat exchange medium flowing in from the inlet c1 of the third heat exchange branch 303 through the plate heat exchanger 320 and the heater 350, and then flow from the outlet c2 of the third heat exchange branch 303 to the first switching device 330. Finally, the first switching device 330 determines whether the heat exchange medium flows to the first heat exchange branch 301 or to the second heat exchange branch 302.

[0056] Continue to refer to Figure 2In some embodiments, the temperature control system 300 further includes a second pump body 3041 disposed in the fourth heat exchange branch 304. The second pump body 3041 may be disposed between the inlet d1 of the fourth heat exchange branch 304 and the dry cooler 310. When the second pump body 3041 is working, it can drive the heat exchange medium flowing in from the inlet d1 of the fourth heat exchange branch 304 through the dry cooler 310 and then flow from the outlet d2 of the fourth heat exchange branch 304 to the first switching device 330. Finally, the first switching device 330 determines whether the heat exchange medium flows to the first heat exchange branch 301 or to the second heat exchange branch 302.

[0057] In some embodiments, the temperature control system 300 has a first working mode [1]. In the first working mode, the control module controls the refrigerant circulation loop 305 to work, controls the first switching device 330 to connect the outlet c2 of the third heat exchange branch 303 to the inlet a1 of the first heat exchange branch 301 and the inlet b1 of the second heat exchange branch 302, and controls the second switching device 340 to connect the outlet a2 of the first heat exchange branch 301 and the outlet b2 of the second heat exchange branch 302 to the inlet c1 of the third heat exchange branch 303.

[0058] Reference Figure 3 As shown by the dashed arrow, in the first operating mode of this embodiment, the refrigerant circulation loop 305 operates, and the compressor 3051 starts to run in cooling mode. The refrigerant circulating in the refrigerant circulation loop 305 cools the heat exchange medium flowing through the third heat exchange branch 303 through the plate heat exchanger 320. The low-temperature heat exchange medium enters the first switching device 330 from the outlet c2 of the third heat exchange branch 303, and flows through the battery pack 100 from the inlet a1 of the first heat exchange branch 301 and through the energy storage converter 200 from the inlet b1 of the second heat exchange branch 302, thereby cooling the battery pack 100 and the energy storage converter 200. Therefore, it can be understood that the first operating mode of this embodiment is the cooling mode of the temperature control system 300, which is particularly suitable for cooling the battery pack 100 when it is in a medium-to-high temperature state.

[0059] In some embodiments, the temperature control system 300 has a second working mode [2]. In the second working mode, the control module controls the heater 350 to work, controls the first switching device 330 to connect the outlet c2 of the third heat exchange branch 303 to the inlet a1 of the first heat exchange branch 301 and the inlet b1 of the second heat exchange branch 302, and controls the second switching device 340 to connect the outlet a2 of the first heat exchange branch 301 and the outlet b2 of the second heat exchange branch 302 to the inlet c1 of the third heat exchange branch 303.

[0060] Reference Figure 4As shown by the dashed arrow, in the second operating mode of this embodiment, the heater 350 is controlled to operate, and the heater 350 heats the heat exchange medium flowing through the third heat exchange branch 303. The high-temperature heat exchange medium enters the first switching device 330 from the outlet c2 of the third heat exchange branch 303, and flows through the battery pack 100 from the inlet a1 of the first heat exchange branch 301 and through the energy storage converter 200 from the inlet b1 of the second heat exchange branch 302, thereby raising the temperature of the battery pack 100 and the energy storage converter 200. Therefore, it can be understood that the second operating mode of this embodiment is the heating mode of the temperature control system 300, which is suitable for maintaining the temperature of the battery pack 100 during low-temperature charging and discharging under extremely cold ambient temperatures, or for preheating the battery pack 100 when it is not in a charging or discharging state.

[0061] In some embodiments, the temperature control system 300 has a third working mode [3]. In the third working mode, the control module controls the first switching device 330 to connect the outlet d2 of the fourth heat exchange branch 304 to the inlet a1 of the first heat exchange branch 301 and the inlet b1 of the second heat exchange branch 302, and controls the second switching device 340 to connect the outlet a2 of the first heat exchange branch 301 and the outlet b2 of the second heat exchange branch 302 to the inlet d1 of the fourth heat exchange branch 304.

[0062] Continue to refer to Figure 4 As shown by the dashed arrow, in the third operating mode of this embodiment, the heat exchange medium enters the first switching device 330 from the outlet c2 of the third heat exchange branch 303, and flows through the battery pack 100 from the inlet a1 of the first heat exchange branch 301 and through the energy storage converter 200 from the inlet b1 of the second heat exchange branch 302, thereby achieving heat exchange between the battery pack 100 and the energy storage converter 200. It can be understood that the difference between the third operating mode and the second operating mode is only that the heater 350 does not need to be controlled, meaning there is no need to heat the battery pack 100 and the energy storage converter 200. Therefore, the third operating mode is the self-circulation mode of the temperature control system 300. Under the heat exchange effect of the heat exchange medium, the temperature of each area of ​​the battery pack 100 can be balanced, avoiding temperature imbalance. Additionally, the heat generated by the energy storage converter 200 can be recovered and utilized, making it suitable for situations where the temperature is moderate, neither too high nor too low.

[0063] In some embodiments, the temperature control system 300 has a fourth operating mode [4]. In the fourth operating mode, the control module controls the first switching device 330 to connect the outlet d2 of the fourth heat exchange branch 304 to the inlet a1 of the first heat exchange branch 301 and the inlet b1 of the second heat exchange branch 302, and controls the second switching device 340 to connect the outlet a2 of the first heat exchange branch 301 and the outlet b2 of the second heat exchange branch 302 to the inlet d1 of the fourth heat exchange branch 304.

[0064] Reference Figure 5 As shown by the dashed arrow, in the fourth operating mode of this embodiment, the dry cooler 310 performs air cooling on the heat exchange medium flowing through the fourth heat exchange branch 304. The low-temperature heat exchange medium enters the first switching device 330 from the outlet d2 of the fourth heat exchange branch 304, and flows through the battery pack 100 from the inlet a1 of the first heat exchange branch 301 and through the energy storage converter 200 from the inlet b1 of the second heat exchange branch 302, thereby cooling the battery pack 100 and the energy storage converter 200. Therefore, it can be understood that the fourth operating mode of this embodiment is the air cooling mode of the temperature control system 300, which is suitable for scenarios with cooling requirements under medium and low temperature conditions.

[0065] Additionally, refer to Figure 6 In some embodiments, the operating mode of the temperature control system 300 is controlled according to the temperature and charge / discharge state of the battery pack 100, including but not limited to steps S610 to S620:

[0066] Step S610: Obtain the temperature of more than 100 different measurement points of the battery pack, and determine the maximum battery temperature Tmax and the minimum battery temperature Tmin;

[0067] Step S620: Control the working mode of the temperature control system 300 according to the maximum battery temperature Tmax, the minimum battery temperature Tmin and the charging and discharging state of the battery pack 100.

[0068] In this embodiment, temperature sensors are set at multiple measurement points of the battery pack 100 to collect temperature data. The maximum battery temperature Tmax and the minimum battery temperature Tmin are determined from the temperatures at multiple different measurement points. The operating mode of the temperature control system 300 is controlled in combination with the charging and discharging state of the battery pack 100. This ensures that the current operating state of the temperature control system 300 takes into account both the influence of the maximum battery temperature Tmax and the minimum battery temperature Tmin, so that the temperature of the battery pack 100 can be maintained within a suitable range under different conditions, which is beneficial to improving the energy efficiency and safety of the energy storage system.

[0069] In some embodiments, when the battery pack 100 is in a charging and discharging state and the maximum battery temperature Tmax is greater than a first preset value [5]T1, the control module controls the temperature control system 300 to enter the first working mode, that is, controls the temperature control system 300 to enter the cooling mode, for example, referring to Figure 7 The steps are shown in step S701.

[0070] In this embodiment, the first preset value T1 can be set to 35°C, that is, when the maximum battery temperature Tmax > 35°C, the temperature control system 300 enters the cooling mode and uses the refrigerant circulation loop 305 to cool down the battery pack 100, so as to avoid the temperature of the battery pack 100 in the charging and discharging state from continuing to rise and causing safety risks, and to avoid the energy consumption of the energy storage system from being reduced due to the excessive temperature of the battery pack 100.

[0071] In some embodiments, when the battery pack 100 is in a charging and discharging state, and the minimum battery temperature Tmin is less than a second preset value [6]T2, the control module controls the temperature control system 300 to enter the second working mode, that is, controls the temperature control system 300 to enter the heating mode, for example, referring to Figure 7 The steps are shown in step S702.

[0072] In this embodiment, the second preset value T2 can be set to 15°C, that is, when the minimum battery temperature Tmin < 15°C, the temperature control system 300 enters the heating mode and uses the heater 350 to heat up the battery pack 100, so as to avoid the battery pack 100 being too cold during charging and discharging, which would cause the energy consumption of the energy storage system to decrease.

[0073] In some embodiments, the first operating mode has a higher priority than the second operating mode. (Combined with...) Figure 7 As can be seen from the judgment order, this embodiment prioritizes whether the maximum battery temperature Tmax is greater than the first preset value T1. This is because high temperature may pose a safety hazard, therefore the first working mode has a higher priority than the second working mode. Figure 7 Step S701 has a higher priority than step S702. Energy consumption is considered only after there are no safety hazards.

[0074] In some embodiments, when the battery pack 100 is not in a charging or discharging state and the maximum battery temperature Tmax is greater than a third preset value [7]T3, the control module controls the temperature control system 300 to enter the first working mode, that is, controls the temperature control system 300 to enter the cooling mode, for example, referring to Figure 7 As shown in step S705, the third preset value T3 is greater than the first preset value T1.

[0075] In this embodiment, the third preset value T3 can be set to 40°C, meaning that when the maximum battery temperature Tmax > 40°C, the temperature control system 300 enters the cooling mode, utilizing the refrigerant circulation loop 305 to cool the battery pack 100. This prevents the temperature of the battery pack 100 from continuing to rise and causing safety risks when it is not in a charging / discharging state, and also prevents the energy consumption of the energy storage system from decreasing due to excessively high battery pack 100 temperature. Furthermore, since the temperature requirement for the battery pack 100 is lower when it is not in a charging / discharging state, setting the third preset value T3 to be greater than the first preset value T1 allows the activation of the cooling mode when the battery pack 100 is not in a charging / discharging state to occur slightly later than when it is in a charging / discharging state, which is beneficial for further improving energy efficiency.

[0076] In some embodiments, when the battery pack 100 is not in a charging or discharging state and the minimum battery temperature Tmin is less than a fourth preset value [8]T4, the control module controls the temperature control system 300 to enter the second working mode, that is, controls the temperature control system 300 to enter the heating mode, for example, referring to Figure 7 As shown in step S706, the fourth preset value T4 is less than the second preset value T2.

[0077] In this embodiment, the fourth preset value T4 can be set to 5°C, meaning that when the minimum battery temperature Tmin < 5°C, the temperature control system 300 enters the heating mode, using the heater 350 to heat the battery pack 100, preventing the battery pack 100 from being too cold when it is not charging or discharging, thus avoiding a decrease in energy consumption of the energy storage system. Furthermore, since the temperature requirement for the battery pack 100 when it is not charging or discharging is lower, setting the fourth preset value T4 to be less than the second preset value T2 allows the activation of the heating mode when the battery pack 100 is not charging or discharging to occur slightly later than when it is charging or discharging, which is beneficial for further improving energy efficiency.

[0078] In some embodiments, when the battery pack 100 is not in a charging or discharging state, and the difference Δ5 between the maximum battery temperature Tmax and the minimum battery temperature Tmin is greater than the fifth preset value [9]T5, the control module controls the temperature control system 300 to enter the third working mode, that is, controls the temperature control system 300 to enter the self-circulation mode, for example, referring to Figure 7 The steps are shown in step S707.

[0079] In this embodiment, the fifth preset value T5 can be set to 10°C, that is, when the difference Δ5 between the maximum battery temperature Tmax and the minimum battery temperature Tmin is greater than 10°C, the temperature control system 300 enters the self-circulation mode. Under the heat exchange effect of the heat exchange medium, the temperature of each area of ​​the battery pack 100 can be balanced to avoid temperature imbalance of the battery pack 100. In addition, the heat generated by the energy storage converter 200 can also be recovered and utilized.

[0080] In some embodiments, the first operating mode has a higher priority than the second operating mode; the second operating mode has a higher priority than the third operating mode.

[0081] Combination Figure 7 As can be seen from the judgment order, this embodiment prioritizes whether the maximum battery temperature Tmax is greater than the third preset value T3. This is because high temperature may pose a safety hazard, therefore the first working mode has a higher priority than the second working mode. Figure 7 Step S705 has a higher priority than step S706. Energy consumption is considered only after ensuring there are no safety concerns. Furthermore, Figure 7 Step S706 has a higher priority than step S707, prioritizing the prevention of energy loss due to excessively low temperature of the battery pack 100.

[0082] Additionally, in some embodiments, in corresponding to Figure 7 In step S707, in the third operating mode, when the difference ΔT between the maximum battery temperature Tmax and the minimum battery temperature Tmin is less than the sixteenth preset value T16, the control module controls the temperature control system 300 to switch from the third operating mode to the standby mode, for example, referring to... Figure 7 The steps are shown in step S709.

[0083] In this embodiment, the sixteenth preset value T16 can be set to 5°C for example. The difference ΔT between the maximum battery temperature Tmax and the minimum battery temperature Tmin is less than 5°C, indicating that the temperature difference between various parts of the battery pack 100 is not too large. Switching to standby mode at this time is beneficial to reducing the energy consumption of the energy storage system.

[0084] Reference Figure 2 In some embodiments, the temperature control system 300 further includes a dehumidification branch 306 connected in parallel with the first heat exchange channel. The dehumidification branch 306 is equipped with a dehumidifier 360. In the first operating mode, the control module controls the dehumidifier 360 to operate, for example, referring to... Figure 7 The bracketed portions in steps S701 and S705 are shown in the figure.

[0085] Understandably, the dehumidification branch 306 is also equipped with a second electronic expansion 3061. In the first working mode, the refrigerant circulation loop 305 is working. At this time, it is only necessary to turn on the second electronic expansion 3061 so that the refrigerant with a lower temperature can pass through the dehumidifier 360 to achieve dehumidification.

[0086] It should be noted that the primary function of the first electronic expansion 3053 and the second electronic expansion 3061 is to control the refrigerant flow rate. The first electronic expansion 3053 is used to control the refrigerant flow rate entering the plate heat exchanger 320. By adjusting the opening degree of the first electronic expansion 3053, the refrigerant flow rate can be precisely controlled, thereby precisely controlling the heat exchange capacity of the plate heat exchanger 320. In higher temperature environments, the first electronic expansion 3053 can be fully or partially open to allow more refrigerant to flow through the plate heat exchanger 320. In lower temperature environments, the flow rate may be reduced to reduce the cooling effect. It should be understood that in different operating modes, the opening degree of the first electronic expansion 3053 in this embodiment will be adjusted according to requirements to adapt to different thermal management strategies. Similarly, the second electronic expansion 3061 is used to control the refrigerant flow rate to the dehumidifier 360.

[0087] Reference Figure 1 In some embodiments, a high-pressure box 370 is also included, in which the dehumidifier 360 is used to cool and dehumidify the high-pressure box 370 in a first operating mode.

[0088] In this embodiment, when the energy storage system is also equipped with a high-voltage box 370, the dehumidifier 360 takes into account both cooling and dehumidifying the high-voltage box 370, thus preventing the high-voltage box 370 from getting too hot.

[0089] In some embodiments, in corresponding to Figure 7 In step S701, in the first operating mode, when the maximum battery temperature Tmax drops below the sixth preset value T6, the control module controls the temperature control system 300 to switch from the first operating mode to the fourth operating mode, that is, controls the temperature control system 300 to enter the air-cooling mode, using the dry cooler 310 to achieve cooling operation, for example, referring to... Figure 7 The steps are shown in step S704.

[0090] In this embodiment, the sixth preset value T6 can be set to 30°C, that is, in the cooling mode, if the maximum battery temperature Tmax drops from above 35°C to below 30°C, the compressor 3051 in the control medium circulation loop 305 stops working and switches to the lower energy consumption air-cooling mode, which is beneficial to improving the energy efficiency of the energy storage system.

[0091] In some embodiments, in corresponding to Figure 7In step S705, in the first operating mode, when the maximum battery temperature Tmax drops below the eleventh preset value T11, the control module controls the temperature control system 300 to switch from the first operating mode to the fourth operating mode, that is, controls the temperature control system 300 to enter the air-cooling mode, for example, referring to... Figure 7 The steps are shown in step S708.

[0092] Similarly, in this embodiment, the eleventh preset value T11 can be set to 35°C, that is, in the cooling mode of step S705, if the maximum battery temperature Tmax drops from above 40°C to below 35°C, the compressor 3051 in the control medium circulation loop 305 stops working and switches to the lower energy consumption air-cooling mode, which is beneficial to improving the energy efficiency of the energy storage system.

[0093] In some embodiments, in corresponding to Figure 7 In the first working mode of step S701, or in the fourth working mode of step S704, when the maximum battery temperature Tmax drops below the seventh preset value

[10] T7, and the difference ΔT between the maximum battery temperature Tmax and the minimum battery temperature Tmin is less than the eighth preset value

[11] T8, the control module controls the temperature control system 300 to switch from the first working mode to the third working mode, that is, controls the temperature control system 300 to enter the self-circulation mode, for example, referring to Figure 7 The steps are shown in step S703.

[0094] In this embodiment, the seventh preset value T7 can be set to 25°C, and the eighth preset value T8 can be set to 5°C. When the maximum battery temperature Tmax drops below 25°C, it indicates that the battery temperature is no longer high and there is no need for rapid cooling. When the difference ΔT between the maximum battery temperature Tmax and the minimum battery temperature Tmin is less than 5°C, it indicates that the temperature difference between various parts of the battery pack 100 is not too large. At this time, switching to the self-circulation mode, the media circulation loop 305 does not need to be turned on, which is beneficial to reducing the energy consumption of the energy storage system.

[0095] In some embodiments, in corresponding to Figure 7 In the second working mode of step S702, when the minimum battery temperature Tmin rises above the ninth preset value

[12] T9, and the difference ΔT between the maximum battery temperature Tmax and the minimum battery temperature Tmin is less than the tenth preset value

[13] T10, the control module controls the temperature control system 300 to switch from the second working mode to the third working mode, that is, controls the temperature control system 300 to enter the self-circulation mode, for example, referring to Figure 7 The steps are shown in step S703.

[0096] In this embodiment, the ninth preset value T9 can be set to 20°C, and the tenth preset value T10 can be set to 5°C. When the minimum battery temperature Tmin rises to more than 20°C, it means that the battery temperature is no longer low and there is no need for rapid heating. When the difference ΔT between the maximum battery temperature Tmax and the minimum battery temperature Tmin is less than 5°C, it means that the temperature difference between various parts of the battery pack 100 is not too large. At this time, the self-circulation mode is switched, and the heater 350 does not need to be turned on, which helps to reduce the energy consumption of the energy storage system.

[0097] In some embodiments, in corresponding to Figure 7 In the first operating mode of step S705, or in the fourth operating mode of step S708, when the maximum battery temperature Tmax drops below the twelfth preset value T12, and the difference ΔT between the maximum battery temperature Tmax and the minimum battery temperature Tmin is less than the thirteenth preset value T13, the control module controls the temperature control system 300 to switch from the first operating mode to the standby mode, for example, referring to... Figure 7 The steps are shown in step S709.

[0098] In this embodiment, the twelfth preset value T12 can be set to 30°C, and the thirteenth preset value T13 can be set to 5°C. When the maximum battery temperature Tmax drops below 30°C, it means that the battery temperature is no longer high and there is no need for rapid cooling. The difference ΔT between the maximum battery temperature Tmax and the minimum battery temperature Tmin is less than 5°C, which means that the temperature difference between various parts of the battery pack 100 is not too large. At this time, switching to standby mode, the media circulation loop 305 does not need to be turned on, which is beneficial to reducing the energy consumption of the energy storage system.

[0099] In some embodiments, in corresponding to Figure 7 In step S706 of the second operating mode, when the minimum battery temperature Tmin rises above the fourteenth preset value T14, and the difference ΔT between the maximum battery temperature Tmax and the minimum battery temperature Tmin is less than the fifteenth preset value T15, the control module controls the temperature control system 300 to switch from the second operating mode to the standby mode, for example, referring to... Figure 7 The steps are shown in step S709.

[0100] In this embodiment, the fourteenth preset value T14 can be set to 10°C, and the fifteenth preset value T15 can be set to 5°C. When the minimum battery temperature Tmin rises to more than 10°C, it indicates that the battery temperature is no longer low and there is no need for rapid heating. When the difference ΔT between the maximum battery temperature Tmax and the minimum battery temperature Tmin is less than 5°C, it indicates that the temperature difference between various parts of the battery pack 100 is not too large. At this time, switching to standby mode, the heater 350 does not need to be turned on, which helps to reduce the energy consumption of the energy storage system.

[0101] In addition, a second aspect of the present invention provides a new energy system, including the energy storage system described in the first aspect of the present invention.

[0102] According to the new energy system provided in the embodiment of the present invention, when the refrigerant circulation loop 305 in the temperature control system 300 is operating, it can exchange heat with the refrigerant circulation loop 305 through the plate heat exchanger 320. The fourth heat exchange branch 304 where the dry cooler 310 is located can exchange heat with the external environment through the dry cooler 310. The third heat exchange branch 303 is also provided with a heater 350 to heat the heat exchange medium flowing through the third heat exchange branch 303, which can realize a variety of different heat exchange methods. Based on this, the first switching device 330 and the second switching device 34 The control module can control the first heat exchange branch 301 where the battery pack 100 is located and the second heat exchange branch 302 where the energy storage converter 200 is located, and connect them to the third heat exchange branch 303 or the fourth heat exchange branch 304, so as to provide various heat exchange requirements for the battery pack 100 and the energy storage converter 200. In addition, the control module controls the working mode of the temperature control system 300 according to the temperature and charging and discharging state of the battery pack 100, so that the temperature of the battery pack 100 can be maintained within a suitable range under different conditions, which is conducive to improving the energy efficiency of the energy storage system.

[0103] It will be understood by those skilled in the art that all or some of the steps and systems in the methods disclosed above can be implemented as software, firmware, hardware, and suitable combinations thereof. Some or all of the physical components can be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit. Such software can be distributed on a computer-readable medium, which may include computer storage media or non-transitory media and communication media or transient media. As is known to those skilled in the art, the term computer storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information such as computer-readable instructions, data structures, program modules, or other data. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disc DVD or other optical disc storage, magnetic cartridges, magnetic tape, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and is accessible to a computer. Furthermore, as is known to those skilled in the art, communication media typically contain computer-readable instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and may include any information delivery medium.

[0104] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. An energy storage system, characterized in that, It includes a battery pack, an energy storage converter, a temperature control system, and a control module, wherein the energy storage converter is electrically connected to the battery pack, wherein: The temperature control system includes a refrigerant circulation loop, a dry cooler, a first heat exchange branch that exchanges heat with the battery pack, a second heat exchange branch that exchanges heat with the energy storage converter, a third heat exchange branch that exchanges heat with the refrigerant circulation loop via a plate heat exchanger, a fourth heat exchange branch that exchanges heat with the dry cooler, a first switching device, a second switching device, and a heater installed in the third heat exchange branch. The first switching device is connected to the inlet of the first heat exchange branch, the inlet of the second heat exchange branch, the outlet of the third heat exchange branch, and the outlet of the fourth heat exchange branch. The second switching device is connected to the outlet of the first heat exchange branch, the outlet of the second heat exchange branch, the inlet of the third heat exchange branch, and the inlet of the fourth heat exchange branch. The first switching device and the second switching device can control the first heat exchange branch where the battery pack is located and the second heat exchange branch where the energy storage converter is located to be connected to the third heat exchange branch or to the fourth heat exchange branch, so as to realize the switching of different working modes of the temperature control system. The control module is configured as follows: The operating mode of the temperature control system is controlled according to the temperature and charging / discharging state of the battery pack.

2. The energy storage system according to claim 1, characterized in that, The temperature control system has a first working mode. In the first working mode, the control module controls the refrigerant circulation loop to work, controls the first switching device to connect the outlet of the third heat exchange branch to the inlet of the first heat exchange branch and the inlet of the second heat exchange branch, and controls the second switching device to connect the outlet of the first heat exchange branch and the outlet of the second heat exchange branch to the inlet of the third heat exchange branch.

3. The energy storage system according to claim 2, characterized in that, The temperature control system has a second working mode. In the second working mode, the control module controls the heater to work, controls the first switching device to connect the outlet of the third heat exchange branch to the inlet of the first heat exchange branch and the inlet of the second heat exchange branch, and controls the second switching device to connect the outlet of the first heat exchange branch and the outlet of the second heat exchange branch to the inlet of the third heat exchange branch.

4. The energy storage system according to claim 3, characterized in that, The temperature control system has a third working mode. In the third working mode, the control module controls the first switching device to connect the outlet of the fourth heat exchange branch to the inlet of the first heat exchange branch and the inlet of the second heat exchange branch, and controls the second switching device to connect the outlet of the first heat exchange branch and the outlet of the second heat exchange branch to the inlet of the fourth heat exchange branch.

5. The energy storage system according to claim 4, characterized in that, The step of controlling the operating mode of the temperature control system based on the temperature and charging / discharging state of the battery pack includes: The temperature of the battery pack at multiple different measurement points is obtained, and the maximum and minimum battery temperatures are determined. The operating mode of the temperature control system is controlled based on the maximum battery temperature, the minimum battery temperature, and the charging and discharging state of the battery pack.

6. The energy storage system according to claim 5, characterized in that, When the battery pack is in a charging / discharging state and the maximum battery temperature is greater than a first preset value, the control module controls the temperature control system to enter the first working mode.

7. The energy storage system according to claim 6, characterized in that, When the battery pack is in a charging / discharging state and the minimum battery temperature is less than a second preset value, the control module controls the temperature control system to enter the second working mode.

8. The energy storage system according to claim 6, characterized in that, When the battery pack is not in a charging or discharging state, and the maximum battery temperature is greater than a third preset value, the control module controls the temperature control system to enter the first working mode, where the third preset value is greater than the first preset value.

9. The energy storage system according to claim 7, characterized in that, When the battery pack is not in a charging or discharging state, and the minimum battery temperature is less than a fourth preset value, the control module controls the temperature control system to enter the second working mode, where the fourth preset value is less than the second preset value.

10. The energy storage system according to claim 9, characterized in that, When the battery pack is not in a charging or discharging state, and the difference between the maximum battery temperature and the minimum battery temperature is greater than a fifth preset value, the control module controls the temperature control system to enter the third working mode.

11. The energy storage system according to claim 7 or 9, characterized in that, The first working mode has a higher priority than the second working mode.

12. The energy storage system according to claim 10, characterized in that, The second working mode has a higher priority than the third working mode.

13. The energy storage system according to claim 2, characterized in that, The plate heat exchanger has a first heat exchange channel and a second heat exchange channel arranged for mutual heat exchange. The first heat exchange channel is connected to the refrigerant circulation loop, and the second heat exchange channel is connected to the third heat exchange branch.

14. The energy storage system according to claim 13, characterized in that, The temperature control system also includes a dehumidification branch connected in parallel with the first heat exchange channel. The dehumidification branch is equipped with a dehumidifier. In the first working mode, the control module controls the dehumidifier to work.

15. The energy storage system according to claim 14, characterized in that, It also includes a high-pressure box, and in the first working mode, the dehumidifier is used to cool and dehumidify the high-pressure box.

16. The energy storage system according to claim 6, characterized in that, In the first operating mode, when the maximum battery temperature drops below a sixth preset value, the control module controls the temperature control system to switch from the first operating mode to the fourth operating mode; wherein, in the fourth operating mode, the control module controls the first switching device to connect the outlet of the fourth heat exchange branch to the inlet of the first heat exchange branch and the inlet of the second heat exchange branch, and controls the second switching device to connect the outlet of the first heat exchange branch and the outlet of the second heat exchange branch to the inlet of the fourth heat exchange branch.

17. The energy storage system according to claim 6, characterized in that, In the first working mode, when the maximum battery temperature drops below a seventh preset value, and the difference between the maximum battery temperature and the minimum battery temperature is less than an eighth preset value, the control module controls the temperature control system to switch from the first working mode to the third working mode.

18. The energy storage system according to claim 7, characterized in that, In the second working mode, when the minimum battery temperature rises above the ninth preset value, and the difference between the maximum battery temperature and the minimum battery temperature is less than the tenth preset value, the control module controls the temperature control system to switch from the second working mode to the third working mode.

19. A new energy system, characterized in that, Includes the energy storage system as described in any one of claims 1 to 18.

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