Energy storage system, and liquid cooling system and water pump driving apparatus thereof

Abstract

The present application relates to the technical field of energy storage systems. Provided are an energy storage system, and a liquid cooling system and a water pump driving apparatus thereof. The water pump driving apparatus comprises a first module and a second module, wherein an input end of the first module serves as a first power input end of the water pump driving apparatus, and receives alternating-current auxiliary power-supply electric energy of an energy storage system; an input end of the second module serves as a second power input end of the water pump driving apparatus, and is connected to a backup power supply in the energy storage system; and an output end of the first module and an output end of the second module are each used for supplying power to a water pump by means of an output end of the water pump driving apparatus. When there is a loss of alternating-current auxiliary power-supply electric energy, the water pump driving apparatus can use a second module thereof to provide backup power-supply electric energy for a water pump, such that the operation of the water pump can be ensured, thereby enabling a liquid cooling system to perform heat dissipation on an energy storage system by means of liquid cooling. After the alternating-current auxiliary power-supply electric energy is restored, the water pump driving apparatus can also automatically switch back to using the electric energy, thereby avoiding unnecessary consumption of electric energy of a backup power supply.

Description

Energy storage system, liquid cooling system and water pump driving device thereof

[0001] The present application claims priority to the Chinese patent application No. 202410873262.2, filed on June 28, 2024, and entitled "Energy storage system, liquid cooling system and water pump driving device thereof", the content of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0002] The present application relates to the technical field of energy storage systems, in particular to an energy storage system, a liquid cooling system and a water pump driving device thereof. BACKGROUND

[0003] At present, the energy storage system can adopt liquid cooling technology. In the working process of liquid cooling in the liquid cooling system, the water pump usually receives the AC auxiliary power supply energy of the energy storage system through the corresponding frequency converter, so that the water pump can drive the cooling liquid to flow in the related pipeline, thereby realizing the liquid cooling of the energy storage system.

[0004] However, the current liquid cooling system cannot realize the operation of the water pump and thus cannot realize liquid cooling in the case of lack of AC auxiliary power supply energy.

[0005] SUMMARY

[0006] In view of the above problems, in order to solve the problem that the liquid cooling system in the prior art cannot realize the operation of the water pump and thus cannot realize liquid cooling in the case of lack of AC auxiliary power supply energy, the present application provides an energy storage system, a liquid cooling system and a water pump driving device thereof. The specific solutions are as follows:

[0007] The first aspect of the present application provides a water pump driving device of a liquid cooling system, comprising: a first module and a second module; wherein,

[0008] The input end of the first module is the first power supply input end of the water pump driving device, and receives the AC auxiliary power supply energy of the energy storage system where the liquid cooling system is located;

[0009] The input end of the second module is the second power supply input end of the water pump driving device, and is connected to the standby power supply in the energy storage system;

[0010] The output end of the first module and the output end of the second module are respectively used to supply power to the water pump in the liquid cooling system through the output end of the water pump driving device.

[0011] In a possible implementation, the standby power supply is a lithium battery in the energy storage system, or an uninterruptible power supply (UPS) in the energy storage system.

[0012] In a possible implementation, the water pump is a direct-current water pump.

[0013] The first module is an AC / DC converter.

[0014] The output end of the first module and the output end of the second module are connected to the output end of the water pump driving device respectively.

[0015] In a possible implementation, when the backup power supply is a lithium battery in the energy storage system, the second module is a DC / DC converter.

[0016] When the backup power supply is an UPS in the energy storage system, the second module is an AC / DC converter.

[0017] In a possible implementation, the water pump is an alternating-current fixed-frequency water pump.

[0018] The first module is a transfer switch.

[0019] The output end of the first module is connected to the output end of the water pump driving device.

[0020] The output end of the second module is connected to the other input end of the transfer switch.

[0021] In a possible implementation, when the backup power supply is a lithium battery in the energy storage system, the second module is a DC / AC converter.

[0022] In a possible implementation, the water pump is an alternating-current variable-frequency water pump.

[0023] The first module comprises an AC / DC converter and a DC / AC converter; the alternating-current side of the AC / DC converter serves as the input end of the first module, the direct-current side of the AC / DC converter is connected to the direct-current side of the DC / AC converter, and the alternating-current side of the DC / AC converter serves as the output end of the first module.

[0024] The output end of the first module is connected to the output end of the water pump driving device.

[0025] The output end of the second module is connected to the direct-current side of the DC / AC converter.

[0026] In a possible implementation, when the backup power supply is a lithium battery in the energy storage system, the second module is a DC / DC converter.

[0027] When the backup power supply is an UPS in the energy storage system, the second module is an AC / DC converter.

[0028] In a possible implementation, the water pump driving device further includes two diodes.

[0029] The first module and the second module are connected in parallel through the corresponding diode.

[0030] The voltage of the first module at the parallel connection position is greater than the voltage of the second module at the parallel connection position.

[0031] In a possible implementation, the switch is configured to have a priority of using the AC auxiliary power higher than the output power of the second module.

[0032] In a possible implementation, the water pump driving device further includes a contactor.

[0033] One end of the contactor is connected to the input end of the second module, and the other end of the contactor is configured to be connected to the backup power supply.

[0034] The second aspect of the present application provides a water pump driving device of a liquid cooling system, comprising: a switch; wherein,

[0035] One input end of the switch is configured to receive AC auxiliary power of an energy storage system in which the liquid cooling system is located, as a first power input end of the water pump driving device.

[0036] The other input end of the switch is connected to an UPS in the energy storage system, as a second power input end of the water pump driving device.

[0037] The output end of the switch is configured to supply power to a water pump in the liquid cooling system, as an output end of the water pump driving device.

[0038] In a possible implementation, the switch is configured to have a priority of using the AC auxiliary power higher than the output power of the UPS.

[0039] The third aspect of the present application provides a liquid cooling system, comprising: a liquid cooling terminal, a liquid cooling pipeline, a liquid cooling unit, at least one water pump and a driving device thereof; wherein,

[0040] The liquid cooling terminal is configured to exchange heat with a heat source.

[0041] The liquid cooling pipeline is in communication with the liquid cooling terminal and is configured to transport cooling liquid.

[0042] The liquid cooling unit is configured to compress and cool the cooling liquid.

[0043] The water pump is configured to drive the cooling liquid to flow.

[0044] The driving device is used for driving the corresponding water pump to operate, and is a water pump driving device of the liquid cooling system as described in the first aspect, the second aspect, or any implementation form of the two.

[0045] The fourth aspect of the present application provides a kind of energy storage system, comprising: battery system, energy storage converter PCS and the liquid cooling system as described in the third aspect or any implementation form of the third aspect;

[0046] The liquid cooling system is used to liquid cooling heat dissipation of the battery system and / or the PCS;

[0047] The battery system is connected with the direct current side of the PCS;

[0048] The alternating current side of the PCS is used to connect power grid and / or load, and is used to provide alternating current auxiliary power supply electric energy for the driving device of water pump in the liquid cooling system.

[0049] The water pump driving device of the liquid cooling system provided by the present application can be powered by the first module receiving the alternating current auxiliary power supply electric energy of the energy storage system, or can be powered by the second module connecting the standby power supply in the energy storage system. Therefore, when the alternating current auxiliary power supply electric energy is missing, the water pump driving device provided by the present application can provide standby power supply electric energy for the water pump by the second module, to ensure that the operation of the water pump can be realized, and then the liquid cooling system can liquid cooling heat dissipation of the energy storage system. BRIEF DESCRIPTION OF DRAWINGS

[0050] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the drawings needed in the embodiment or prior art description will be briefly introduced below. Obviously, the drawings in the following description are only embodiments of the present application, and those skilled in the art can obtain other drawings according to the provided drawings without creating any creative labor.

[0051] Fig. 1 is a structural schematic diagram of a water pump driving device of a liquid cooling system provided by an embodiment of the present application;

[0052] Fig. 2 is a structural schematic diagram of another water pump driving device of a liquid cooling system provided by an embodiment of the present application;

[0053] Fig. 3 is a structural schematic diagram of another water pump driving device of a liquid cooling system provided by an embodiment of the present application;

[0054] Fig. 4 is a structural schematic diagram of another water pump driving device of a liquid cooling system provided by an embodiment of the present application;

[0055] Fig. 5 is a structural schematic diagram of another water pump driving device of a liquid cooling system provided by an embodiment of the present application;

[0056] Fig. 6 is a structural schematic diagram of a water pump driving device of another liquid cooling system according to an embodiment of the present application;

[0057] Fig. 7 is a structural schematic diagram of a water pump driving device of another liquid cooling system according to an embodiment of the present application. DETAILED DESCRIPTION

[0058] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0059] At present, liquid cooling technology is used in large ground power station energy storage systems and industrial and commercial energy storage systems to cool the battery system. In addition, liquid cooling technology is also used in some energy storage systems to cool the PCS (Power Conversion System, energy storage converter). Because the heat conduction capacity of liquid is usually better than that of air, the liquid cooling method is superior to the air cooling method in terms of cooling efficiency. In addition, because the liquid cooling method reduces the need for complex pipes and cooling fins, it is superior to the air cooling method in terms of structural design size.

[0060] The water pump of the liquid cooling system in the energy storage system is usually driven by a corresponding frequency converter, and the AC auxiliary power supply energy of the energy storage system is the only power source of the frequency converter. Therefore, when the energy storage system is black started or continuously low-voltage passed through, the energy storage system cannot provide AC auxiliary power supply energy, so that the water pump cannot operate without AC auxiliary power supply energy, causing heat accumulation in the PCS during the starting process and the liquid cooling system cannot effectively cool down, ultimately leading to failure of black start or continuous low-voltage passing.

[0061] Based on this, the water pump driving device of the liquid cooling system is provided to provide backup power supply energy for the water pump in the absence of AC auxiliary power supply energy, so that the water pump can operate normally, and then the liquid cooling system can normally perform liquid cooling. The technical solutions of the present application will be described in detail below with reference to the drawings.

[0062] Referring to Fig. 1, the water pump driving device 20 includes a first module 21 and a second module 22. Wherein:

[0063] The input end of the first module 21 is the first power supply input end of the water pump driving device 20, which receives the AC auxiliary power supply energy of the energy storage system in which the liquid cooling system is located.

[0064] The input end of the second module 22 is connected with the standby power supply in the energy storage system as the second power input end of the water pump driving device 20. The standby power supply can be a lithium battery in the energy storage system or an UPS (Uninterruptible Power Supply) in the energy storage system, which is not limited here according to the specific application environment.

[0065] The output end of the first module 21 and the output end of the second module 22 are respectively used to supply power to the water pump 10 in the liquid cooling system through the output end of the water pump driving device 20.

[0066] That is, the water pump driving device 20 can receive the original AC auxiliary power supply electric energy through the internal first module 21 and receive the electric energy provided by the standby power supply through the internal second module 22, thereby having two power supply branches. The water pump 10 can be powered by the first module 21 receiving the AC auxiliary power supply electric energy of the energy storage system, or the water pump 10 can be powered by the second module 22 connecting the standby power supply in the energy storage system to provide electric energy. When the energy storage system normally exists AC auxiliary power supply electric energy, the AC auxiliary power supply electric energy can be normally received to drive the water pump 10 to operate; when the AC auxiliary power supply electric energy is lost due to black start or continuous low voltage ride through of the energy storage system, the water pump 10 can be ensured to operate normally by receiving the electric energy provided by the standby power supply, so that the PCS can be normally cooled and will not fail due to heat accumulation.

[0067] The water pump driving device 20 of the liquid cooling system provided in the embodiment can provide standby power supply electric energy for the water pump 10 through the second module when the AC auxiliary power supply electric energy is lost, so as to ensure that the water pump 10 can operate, and the liquid cooling system can cool and dissipate heat for the energy storage system, thereby promoting the energy storage system to successfully complete black start or to normally pass through the low voltage ride through working condition.

[0068] It should be noted that the water pump 10 in the liquid cooling system can be a direct-current water pump, an AC constant-frequency water pump, or an AC variable-frequency water pump. Therefore, in order to meet the driving requirements of different types of water pumps, each module in the water pump driving device 20 can have multiple implementation forms. The embodiment gives some specific examples of the implementation form of the water pump driving device 20 based on the previous embodiment, such as:

[0069] (1) For the case that the water pump 10 is a direct-current water pump:

[0070] At this time, the first module 21 needs to convert the received AC auxiliary power supply electric energy into DC electric energy that the DC water pump can receive, therefore, the first module 21 is an AC / DC converter.

[0071] The first module 21 and the second module 22 can be connected in parallel through respective output ends to the output end of the water pump driving device 20, so that when any module is running, the corresponding DC electric energy can be provided to the DC water pump through the output end of the water pump driving device 20.

[0072] For the second module 22, if the standby power supply connected thereto is a lithium battery of the energy storage system, the electric energy received by the input end thereof is also DC electric energy, at this time, the second module 22 is a DC / DC converter (as shown in FIG. 2); and if the standby power supply connected thereto is an UPS 30 of the energy storage system, because the electric energy of the UPS 30 is AC electric energy, the electric energy received by the input end of the second module 22 will be AC electric energy, at this time, the second module 22 is an AC / DC converter (as shown in FIG. 3).

[0073] (2) For the case that the water pump 10 is an AC constant frequency water pump:

[0074] At this time, the first module 21 needs to convert the received AC auxiliary power supply electric energy into AC electric energy that the AC constant frequency water pump can receive, in actual application, the AC constant frequency water pump can adopt the same frequency as the AC auxiliary power supply electric energy, therefore, the first module 21 can adopt a conversion switch to realize; the conversion switch is a switch appliance for conversion of two or more power supplies or loads, and then through two input ends of the conversion switch, electric energy of different sources can be received respectively.

[0075] That is, one input end of the conversion switch can be used to receive the AC auxiliary power supply electric energy; the other input end of the conversion switch can be connected with the output end of the second module 22 to receive the electric energy output by the second module 22; the output end of the conversion switch, that is, the output end of the first module 21, is connected with the output end of the water pump driving device 20; and then through the conversion switch, the electric energy received by any input end thereof can be selected to provide corresponding electric energy for the AC constant frequency water pump.

[0076] For the second module 22, since it needs to connect the AC constant frequency water pump through the switch, it also outputs AC power; therefore, if the standby power supply connected thereto is the lithium battery of the energy storage system, the power received at the input end thereof is DC power, at which time the second module 22 is a DC / AC converter (as shown in FIG. 4); and if the standby power supply connected thereto is the UPS 30 of the energy storage system, the power received at the input end thereof will be AC power, and the second module 22 can be set as an AC / AC converter (not shown in the figure).

[0077] It should be noted that when the standby power supply is the UPS 30, especially when the AC constant frequency water pump can adopt the frequency and voltage of the AC power provided by the UPS 30, in order to reduce the loss and improve the efficiency, the above-mentioned AC / AC converter can be omitted, that is, the second module 22 can be omitted; at this time, the structure of the water pump driving device 20 is shown in FIG. 5, which only retains the above-mentioned first module 21, that is, only includes a switch; at this time, one input end of the switch, as the first power input end of the water pump driving device 20, receives the AC auxiliary power supply power; the other input end of the switch, as the second power input end of the water pump driving device 20, is connected to the UPS 30; the output end of the switch, as the output end of the water pump driving device 20, supplies power to the water pump 10 in the liquid cooling system.

[0078] (3) For the case that the water pump 10 is an AC variable frequency water pump:

[0079] Compared with the DC water pump, the speed of the AC variable frequency water pump can be adjusted according to the frequency of the power supply, and the energy efficiency ratio is higher, so it is more power-saving and has lower use cost in use.

[0080] At this time, the first module 21 needs to convert the received AC auxiliary power supply power into AC power that can be received by the AC variable frequency water pump, therefore, the first module 21 can include an AC / DC converter 211 and a DC / AC converter 212 as shown in FIG. 6 or FIG. 7; the AC side of the AC / DC converter 211 is the input end of the first module 21, the DC side of the AC / DC converter 211 is connected to the DC side of the DC / AC converter 212, and the AC side of the DC / AC converter 212 is the output end of the first module 21.

[0081] In the first module 21, the AC auxiliary power supply power is first rectified by the AC / DC converter 211 to convert it into DC power, and then inverted by the DC / AC converter 212 to further convert it into AC power required by the AC variable frequency water pump.

[0082] The output end of the first module 21 is directly connected with the output end of the water pump driving device 20, that is, the corresponding AC power can be provided for the AC variable frequency water pump. In view of the equipment cost, the device reuse rate can be improved, and then the output end of the second module 22 can be connected with the DC side of the AC / DC converter 211 and the DC / AC converter 212, so that the AC / DC converter 211 can be connected with the second module 22 through the DC / AC converter 212. That is, the function of the integrated frequency conversion machine is disassembled, and the second module 22 is connected in parallel between the AC / DC converter 211 and the DC / AC converter 212.

[0083] For the second module 22, it needs to output DC power to the above-mentioned confluence position, therefore, if the standby power supply connected therewith is a lithium battery of the energy storage system, the power received by the input end thereof is also DC power, at this time, the second module 22 is a DC / DC converter (as shown in FIG. 6); and if the standby power supply connected therewith is the UPS 30 of the energy storage system, the power received by the input end thereof will be AC power, and the second module 22 can be set as an AC / DC converter (as shown in FIG. 7).

[0084] It should be noted that the output end of the second module 22 can also be connected with the output end of the water pump driving device 20, at this time, the second module 22 needs to be connected with the output end of the first module 21 in confluence. Moreover, if the standby power supply connected therewith is a lithium battery of the energy storage system, at this time, the second module 22 is a DC / AC converter (not shown); and if the standby power supply connected therewith is the UPS 30 of the energy storage system, the second module 22 is an AC / AC converter (not shown).

[0085] The embodiment gives some optional examples for the structure of the water pump driving device 20, which can be set according to the type of the water pump 10 driven thereby, so as to expand the application scenarios.

[0086] On the basis of the above-mentioned embodiment, the embodiment gives some more preferred perfect schemes for the implementation mode of the water pump driving device 20 with different structures, such as:

[0087] (1) In order to realize the confluence between the first module 21 and the second module 22, a corresponding diode can be added, so that the two can realize the confluence of the top, that is, the output of the top is realized at the confluence position.

[0088] The output of the top refers to the output of the voltage of the two output power, and the voltage of the smaller one cannot be output.

[0089] As shown in FIG. 2, FIG. 3, FIG. 6 and FIG. 7, the voltage amplitude of the first module 21 output at the confluence position is V1, and the voltage amplitude of the second module 22 output at the confluence position is V2. In actual application, V1>V2 can be set, and then when the AC auxiliary power supply exists normally, the first module 21 and the second module 22 can continue to output the energy of the larger voltage at the confluence position to the rear according to the voltage size, and the energy of the smaller voltage is no longer continued to output to the rear. Moreover, due to the reverse blocking effect of the diode connected to the second module 22, the energy of the larger voltage can also be prevented from being backfed to the second module 22.

[0090] Taking the structure shown in FIG. 2 as an example, the positive output end of the first module 21 is connected to the anode of the first diode D1, the positive output end of the second module 22 is connected to the anode of the second diode D2, and the cathodes of the two diodes are connected to the corresponding confluence position. Due to the setting of V1>V2, when the energy of the AC auxiliary power supply is lost due to the black start or continuous low voltage ride through of the energy storage system, the energy provided by the standby power supply can be received by the second module 22, the output energy of the second module 22 is used to supply power to the water pump 10, so that the water pump 10 can operate normally. When the AC auxiliary power supply is restored, the first module 21 outputs the energy, and the voltage is higher, so that the energy at the confluence position is provided by the first module 21 with higher output voltage, thereby the use priority of the energy of the AC auxiliary power supply is higher than that of the energy of the standby power supply, the release of the energy of the standby power supply can be reduced, and power loss can be avoided. Moreover, at this time, the second diode D2 is reversely blocked, so that the energy at the confluence position cannot be backfed to the second module 22. The situation shown in FIG. 3 is the same as this, and will not be described in detail.

[0091] For the case that the water pump 10 is an AC variable frequency water pump, if the first module 21 and the second module 22 are connected at the output end of the water pump driving device 20 for AC confluence, the use priority setting of different energies described above cannot be simply realized by the above-mentioned diode pair output scheme, therefore, in actual application, the DC confluence scheme shown in FIG. 6 and FIG. 7 can be used. The confluence position in the DC confluence scheme shown in FIG. 2, FIG. 3, FIG. 6 and FIG. 7 is the DC bus of the water pump driving device 20.

[0092] For the case shown in FIG. 6 and FIG. 7, the output voltage amplitude V1 of the AC / DC converter 211 is set to be greater than the output voltage amplitude V2 of the DC / DC converter, and the use priority setting of different energies described above can also be realized, so that the use priority of the energy of the AC auxiliary power supply is higher than that of the energy of the standby power supply, and then the energy of the standby power supply can be avoided to be used when the AC auxiliary power supply exists normally.

[0093] (2) For the case that the AC auxiliary power and the power of the backup power supply are transmitted to the water pump 10 through the transfer switch, in order to avoid using the power of the backup power supply when the AC auxiliary power normally exists, an intelligent transfer switch can be used and priority setting can be performed on the transfer switch, and the use priority of the transfer switch for receiving the power of different input ends is set as: the AC auxiliary power is higher than the output power of the second module 22.

[0094] As shown in FIGS. 4 and 5, the use priority of the AC auxiliary power can be set to be higher than the output power of the second module 22, the input end with higher priority of the transfer switch receives the AC auxiliary power, and the input end with lower priority of the transfer switch receives the power of the backup power supply. When the AC auxiliary power normally exists, the water pump 10 is directly powered by the AC auxiliary power through the transfer switch; when the AC auxiliary power is lost, the circuit of the water pump 10 powered by the output end of the second module 22 is connected through the transfer switch, and then the water pump 10 is powered by the backup power supply; after the AC auxiliary power is restored, the power supply of the water pump 10 is switched to the AC auxiliary power with higher priority again.

[0095] (3) The water pump driving device 20 can further include a contactor K.

[0096] As shown in FIGS. 2 to 4 and FIGS. 6 to 7, one end of the contactor K is connected to the input end of the second module 22, and the other end of the contactor K is used to connect the backup power supply.

[0097] When the AC auxiliary power normally exists or is restored after being lost, not only the AC auxiliary power can be used to power the water pump 10, but further, the power consumption of the backup power supply can be avoided by controlling the contactor K to be disconnected.

[0098] In actual application, the contactor K can be set to be in a disconnected state when the remaining power of the backup power supply is less than a preset power threshold, so that the over-discharge of the backup power supply can be avoided.

[0099] In the embodiment, by using the diode pair top output scheme or priority setting, it can be ensured that the AC auxiliary power is used preferentially when the AC auxiliary power normally exists, and when the AC auxiliary power is restored, the AC power supply can be automatically switched, and unnecessary power consumption of the backup power supply can be avoided. In addition, when the AC auxiliary power normally exists and is restored after being lost, the power taking circuit of the backup power supply is disconnected through the contactor K, and the over-discharge of the backup power supply caused by uncontrolled power taking from the backup power supply can be avoided.

[0100] Another embodiment of the present application also provides a liquid cooling system, comprising: a liquid cooling terminal, a liquid cooling pipeline, a liquid cooling unit, at least one water pump and a driving device thereof; wherein the liquid cooling terminal is used for heat exchange with a heat source; in an energy storage system, the heat source can be a battery system and / or a PCS; the liquid cooling pipeline is in communication with the liquid cooling terminal and is used for transmitting cooling liquid; the liquid cooling unit is used for compressing refrigeration of the cooling liquid; the water pump is used for driving the flow of the cooling liquid; and the driving device is used for driving the corresponding water pump to operate.

[0101] The specific structure and working principle of the liquid cooling system can be referred to the prior art, and will not be described here. The number of the internal water pumps is not limited, each water pump can be driven independently by using an independent driving device, or two or more water pumps can be driven by using the same driving device, which is not limited here and is within the protection scope of the present application.

[0102] The driving device is the water pump driving device 20 of the liquid cooling system according to any one of the above embodiments, and the structure and working principle thereof can be referred to the above embodiments, which will not be described here.

[0103] The above water pump driving device 20 is used to supply power to the corresponding water pump to drive the corresponding water pump, which can provide two power supply circuits for the corresponding water pump, and then when the AC auxiliary power supply is missing, such as when the energy storage system is black started or continuously low voltage is passed through, the water pump is powered by the power provided by the standby power supply to drive the water pump, so that the water pump can operate, ensuring the heat dissipation function of the energy storage system, avoiding affecting the success of black start or continuous low voltage passing. Moreover, after the AC auxiliary power supply is restored, the diode against output scheme or priority setting scheme can be used to automatically switch back to use the AC auxiliary power supply, avoiding unnecessary consumption of the standby power supply. In addition, when the AC auxiliary power supply is normally present and then restored after being missing, the standby power supply can be disconnected, thereby avoiding uncontrolled power consumption from the standby power supply and causing the standby power supply to be depleted.

[0104] Based on the same inventive concept, the present application also provides an energy storage system, comprising: a battery system, a PCS and a liquid cooling system according to any one of the above embodiments.

[0105] The battery system is connected to the DC side of the PCS; the AC side of the PCS is used for connecting the power grid and / or the load, and is used for providing AC auxiliary power supply for the driving device of the water pump in the liquid cooling system.

[0106] In actual application, when there is electricity on the AC side of the PCS, electricity can be taken from the AC side of the PCS as the AC auxiliary power supply electricity in the above-mentioned embodiment; and when there is no electricity on the AC side of the PCS, electricity of the power grid can be received as the AC auxiliary power supply electricity.

[0107] The liquid cooling system is used for liquid cooling and heat dissipation of the battery system and / or the PCS.

[0108] When the energy storage system performs black start or continuous low voltage ride through, if the PCS cannot be cooled, the energy storage system can fail in black start or continuous low voltage ride through due to heat accumulation of the PCS. The liquid cooling system adopted in the embodiment can cool and dissipate heat of the PCS by using the water pump driving device in the above-mentioned embodiment, so that the energy storage system will not fail in black start or continuous low voltage ride through due to heat accumulation of the PCS when the energy storage system performs black start or continuous low voltage ride through.

[0109] Moreover, after the AC auxiliary power supply electricity is restored, the AC auxiliary power supply electricity can be automatically switched back to use, so as to avoid unnecessary consumption of the standby power supply electricity. In addition, when the AC auxiliary power supply electricity normally exists and is restored after being lost, the electricity taking circuit of the standby power supply can be disconnected, so as to avoid uncontrolled electricity taking from the standby power supply and causing the standby power supply to be out of power.

[0110] It should be noted that each of the embodiments in the present specification is described in a progressive manner, and each embodiment focuses on the difference from other embodiments, and the same and similar parts between the embodiments can be referred to each other.

[0111] It should also be noted that in this document, the relationship terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. Moreover, the terms "include", "contain" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or equipment. Without more limitation, the element defined by the statement "including a" does not exclude the presence of another identical element in the process, method, article or equipment including the element.

[0112] The foregoing description of the disclosed embodiments enables a person skilled in the art to make or use the application. Modifications of these embodiments will occur to persons of skill in the art, and that the generic principles defined herein can be applied to other embodiments without departing from the spirit or scope of the application. Therefore, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A water pump drive device for a liquid cooling system, characterized in that, include: Module 1 and Module 2; among which, The input terminal of the first module serves as the first power input terminal of the water pump drive device, receiving AC auxiliary power from the energy storage system where the liquid cooling system is located. The input terminal of the second module serves as the second power input terminal of the water pump drive device and is connected to the backup power supply in the energy storage system. The output terminals of the first module and the second module are respectively used to supply power to the water pump in the liquid cooling system through the output terminal of the water pump drive device.

2. The water pump drive device for the liquid cooling system according to claim 1, characterized in that, The backup power supply is either a lithium battery in the energy storage system or an uninterruptible power supply (UPS) in the energy storage system.

3. The water pump drive device for the liquid cooling system according to claim 1, characterized in that, The water pump is a DC water pump; The first module is an AC / DC converter; The output terminals of the first module and the second module are respectively connected to the output terminal of the water pump drive device.

4. The water pump drive device for the liquid cooling system according to claim 3, characterized in that, When the backup power supply is a lithium battery in the energy storage system, the second module is a DC / DC converter; When the backup power supply is a UPS in the energy storage system, the second module is an AC / DC converter.

5. The water pump drive device for the liquid cooling system according to claim 1, characterized in that, The water pump is an AC fixed-frequency water pump; The first module is a changeover switch; The output terminal of the first module is connected to the output terminal of the water pump drive device; The output terminal of the second module is connected to the other input terminal of the changeover switch.

6. The water pump drive device for the liquid cooling system according to claim 5, characterized in that, The backup power supply is a lithium battery in the energy storage system, and the second module is a DC / AC converter.

7. The water pump drive device for the liquid cooling system according to claim 1, characterized in that, The water pump is an AC variable frequency water pump; The first module includes an AC / DC converter and a DC / AC converter; the AC side of the AC / DC converter serves as the input terminal of the first module, the DC side of the AC / DC converter is connected to the DC side of the DC / AC converter, and the AC side of the DC / AC converter serves as the output terminal of the first module. The output terminal of the first module is connected to the output terminal of the water pump drive device; The output of the second module is connected to the DC side of the DC / AC converter.

8. The water pump drive device for the liquid cooling system according to claim 7, characterized in that, When the backup power supply is a lithium battery in the energy storage system, the second module is a DC / DC converter; When the backup power supply is a UPS in the energy storage system, the second module is an AC / DC converter.

9. The water pump drive device for the liquid cooling system according to claim 3, 4, 7 or 8, characterized in that, Also includes: Two diodes; The first module and the second module each achieve top-to-top current convergence through a corresponding diode; The voltage of the first module at the bus stop is greater than the voltage of the second module at the bus stop.

10. The water pump drive device for the liquid cooling system according to claim 5 or 6, characterized in that, The priority setting of the transfer switch for the use of power received at different input terminals is as follows: the AC auxiliary power supply power is higher than the output power of the second module.

11. The water pump drive device for the liquid cooling system according to any one of claims 3 to 8, characterized in that, Also includes: Contactor; One end of the contactor is connected to the input terminal of the second module, and the other end of the contactor is used to connect to the backup power supply.

12. A water pump drive device for a liquid cooling system, characterized in that, Includes: a changeover switch; wherein, One input terminal of the changeover switch serves as the first power input terminal of the water pump drive device, receiving AC auxiliary power from the energy storage system where the liquid cooling system is located. The other input terminal of the transfer switch serves as the second power input terminal of the water pump drive device and is connected to the UPS in the energy storage system. The output terminal of the changeover switch serves as the output terminal of the water pump drive device, supplying power to the water pump in the liquid cooling system.

13. The water pump drive device for the liquid cooling system according to claim 12, characterized in that, The priority setting of the transfer switch for the use of power received at different input terminals is as follows: the AC auxiliary power supply power is higher than the output power of the UPS.

14. A liquid cooling system, characterized in that, include: Liquid cooling terminal, liquid cooling pipeline, liquid cooling unit, at least one water pump and its drive device; wherein, The liquid-cooled terminal is used for heat exchange with the heat source; The liquid cooling pipeline is connected to the liquid cooling terminal and is used to transmit coolant; The liquid cooling unit is used for compressing and cooling the coolant; The water pump is used to drive the flow of the coolant; The drive device is used to drive the corresponding water pump to operate, and is a water pump drive device for a liquid cooling system as described in any one of claims 1 to 13.

15. An energy storage system, characterized in that, include: The battery system, the energy storage converter PCS, and the liquid cooling system as described in claim 14; The liquid cooling system is used to perform liquid cooling heat dissipation on the battery system and / or the PCS; The battery system is connected to the DC side of the PCS; The AC side of the PCS is used to connect to the power grid and / or load, and to provide AC auxiliary power to the drive device of the water pump in the liquid cooling system.

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