Multi-loop liquid cooling system for liquid cooling unit

Abstract

The utility model provides a multi-loop liquid cooling system for a liquid cooling unit. The multi-loop liquid cooling system comprises a refrigerating device, a first water pump, an electric valve and a three-way regulating valve, the battery and the converter are arranged in parallel, the first heat exchanger is connected with a cold plate pipeline of the battery through a first circulating pipeline, and the first heat exchanger is connected with a cold plate pipeline of the converter through a second circulating pipeline; the first water pump is connected in series between the cold plate of the battery and the first heat exchanger; the output end of the first water pump is also connected with one end of the electric valve; the first input end and the output end of the three-way regulating valve are connected in series between the cold plate of the converter and the first heat exchanger, and the second input end of the three-way regulating valve is also connected with the other end of the electric valve. When the environment temperature is larger than a first temperature threshold value, the first water pump operates, and the refrigerating device provides different refrigerating fluid temperatures for the battery and the converter through the first circulating pipeline and the second circulating pipeline so as to conduct graded refrigerating heat exchange. The comprehensive energy efficiency of the liquid cooling unit can be improved, and the energy consumption can be reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of liquid cooling unit, more particularly to a kind of multi-loop liquid cooling system for liquid cooling unit. BACKGROUND

[0002] Energy storage has been widely applied in power supply side, power grid side, user side, centralized renewable energy grid-connected, auxiliary service and other fields, which has important practical significance for energy saving and emission reduction, reliability improvement, power quality improvement, renewable energy penetration rate improvement and income value-added.

[0003] The current battery cooling is mainly air-cooled heat dissipation, but air-cooled heat dissipation has problems such as low battery pack heat dissipation efficiency, large system noise and poor product environmental adaptability, which brings challenges to the popularization and application of energy storage system. Liquid cooling system has the advantages of high heat transfer coefficient, large specific heat capacity and fast cooling speed, and liquid cooling has become the mainstream of battery thermal management. Secondly, with the progress of technology, the air-cooled power conversion system (PCS) used now is also upgraded to liquid cooling to improve efficiency and service life. The existing outdoor cabinet liquid cooling system generally provides cooling for the PCS and the battery through a series connection mode, but the working temperature range of the battery and the working temperature range of the PCS are quite different, and the series connection mode is easy to cause large energy consumption, which puts higher requirements on the liquid cooling unit. Therefore, how to efficiently cool and heat the battery and the PCS through multiple loops and improve the overall energy efficiency of the liquid cooling unit is of great significance. UTILITY MODEL CONTENTS

[0004] The utility model provides a kind of multi-loop liquid cooling system for liquid cooling unit, solve the cooling of battery and power conversion unit of existing liquid cooling unit without grading, there is large energy consumption, the problem of not energy saving, can improve the annual overall energy efficiency of liquid cooling unit, reduce energy consumption.

[0005] To achieve the above object, the utility model provides the following technical scheme:

[0006] A kind of multi-loop liquid cooling system for liquid cooling unit, comprising: refrigeration device, first water pump, electric valve and three-way regulating valve;

[0007] Battery and power conversion unit are arranged in the two ends of the first heat exchanger in the refrigeration device in parallel;

[0008] The first heat exchanger of the refrigeration device is connected with the cold plate pipe of battery through first circulation pipeline, and the first heat exchanger is connected with the cold plate pipe of power conversion unit through second circulation pipeline;

[0009] The first water pump is connected between the cold plate of battery and the first heat exchanger, and the output end of the first water pump is also connected with one end of the electric valve.

[0010] The first input end of the three-way regulating valve is connected in series between the cold plate of the converter and the first heat exchanger, and the second input end of the three-way regulating valve is also connected to the other end of the electric valve;

[0011] The three-way regulating valve is used to adjust the flow ratio of the refrigerant at the inlet to adjust the refrigerant temperature of the cold plate of the converter.

[0012] When the ambient temperature is greater than the first temperature threshold, the first water pump is operated, and the refrigeration device provides different refrigerant temperatures to the battery and the converter through the first circulation pipeline and the second circulation pipeline respectively to perform staged refrigeration heat exchange.

[0013] Preferably, it further comprises an air-cooled radiator.

[0014] One end of the air-cooled radiator is connected to the output end of the first water pump, and the other end of the air-cooled radiator is connected to the first input end of the three-way regulating valve and the cold plate of the battery respectively.

[0015] When the ambient temperature is less than the second temperature threshold, the refrigeration device is not started, and the first water pump is operated to perform staged refrigeration heat exchange on the battery and the converter through the air-cooled radiator, wherein the second temperature threshold is less than the first temperature threshold.

[0016] Preferably, the refrigeration device further comprises a compressor, an expansion valve, a second heat exchanger, and a liquid accumulator.

[0017] The first heat exchanger, the compressor, the second heat exchanger, the liquid accumulator, and the expansion valve are sequentially arranged on a refrigerant circulation pipeline, the first heat exchanger serves as an evaporator, and the second heat exchanger serves as a condenser. When the compressor is operated, the refrigerant absorbs heat through the first heat exchanger for refrigeration and is liquefied and releases heat through the second heat exchanger.

[0018] Preferably, the refrigerant side of the second heat exchanger is connected to the air-cooled radiator pipeline through a third circulation pipeline, so that the second heat exchanger exchanges heat with the outside through the air-cooled radiator.

[0019] Preferably, it further comprises a second water pump.

[0020] The second water pump is arranged on the third circulation pipeline, and the second water pump is connected in series between the air-cooled radiator and the second heat exchanger. When the second water pump is operated, the refrigerant in the third circulation pipeline is driven to circulate to make the air-cooled radiator dissipate the heat discharged by the second heat exchanger.

[0021] Preferably, it further comprises a pipeline heater.

[0022] The pipeline heater is arranged on the first circulation pipeline and connected in series between the refrigerant output end of the first heat exchanger and the input end of the cold plate of the battery.

[0023] When the temperature of the battery cell is less than a third temperature threshold, the pipeline heater is used to heat the refrigerant in the first circulation pipeline to keep the refrigerant temperature of the cold plate of the battery within a set range, wherein the third temperature threshold is less than 14℃.

[0024] Preferably, the first heat exchanger and the second heat exchanger are both plate heat exchangers.

[0025] Preferably, the first electromagnetic valve, the second electromagnetic valve, the third electromagnetic valve and the fourth electromagnetic valve are further included.

[0026] The first electromagnetic valve is connected in series between the output end of the first water pump and the refrigerant input end of the first heat exchanger.

[0027] The second electromagnetic valve is connected in series between the output end of the first water pump and the air-cooled radiator.

[0028] The third electromagnetic valve is connected in series between the refrigerant output end of the second heat exchanger and the air-cooled radiator.

[0029] The fourth electromagnetic valve is connected in series between the refrigerant output end of the first heat exchanger and the refrigerant output end of the second heat exchanger.

[0030] When the ambient temperature is greater than a first temperature threshold and the refrigeration device is started, the second electromagnetic valve and the fourth electromagnetic valve are both turned off, so that the first water pump drives the refrigerant in the first circulation pipeline and the second circulation pipeline to circulate, and the third circulation pipeline is driven to circulate by the second water pump.

[0031] When the ambient temperature is less than a second temperature threshold and the refrigeration device is not started, the first electromagnetic valve and the third electromagnetic valve are both turned off, and the second electromagnetic valve and the fourth electromagnetic valve are turned on, so that the air-cooled radiator is used to refrigerate and exchange heat with the battery and the inverter.

[0032] Preferably, the first electric three-way valve, the second electric three-way valve, the third electric three-way valve and the fourth electric three-way valve are further included.

[0033] The first end of the first electric three-way valve is connected to the output end of the first water pump, the second end of the first electric three-way valve is connected to the refrigerant input end of the first heat exchanger, and the third end of the first electric three-way valve is connected to the first port of the second electric three-way valve.

[0034] The second port of the second electric three-way valve is connected with the refrigerant output end of the second heat exchanger, and the third port of the second electric three-way valve is connected with one end of the air-cooled radiator;

[0035] The first port of the third electric three-way valve is connected with one end of the pipe heater, the second port of the third electric three-way valve is connected with the refrigerant output end of the first heat exchanger and the first input end of the three-way regulating valve respectively, and the third port of the third electric three-way valve is connected with the first port of the fourth electric three-way valve;

[0036] The second port of the fourth electric three-way valve is connected with the input end of the second water pump, and the third port of the fourth electric three-way valve is connected with the other end of the air-cooled radiator;

[0037] When the ambient temperature is greater than the first temperature threshold and the refrigeration device is started, the pipeline flow between the first electric three-way valve and the second electric three-way valve is closed, the pipeline flow between the third electric three-way valve and the fourth electric three-way valve is closed, the first heat exchanger exchanges heat with the battery and the inverter through the first circulating pipeline and the second circulating pipeline, and the second heat exchanger exchanges heat with the air-cooled radiator through the third circulating pipeline;

[0038] When the ambient temperature is less than the second temperature threshold and the refrigeration device is not started, the pipeline flow between the first electric three-way valve and the third electric three-way valve is closed, the pipeline flow between the second electric three-way valve and the fourth electric three-way valve is closed, and the air-cooled radiator exchanges heat with the battery and the inverter.

[0039] Preferably, the refrigeration device further comprises an expansion tank and a liquid supplement tank.

[0040] The expansion tank and the liquid supplement tank are arranged on the corresponding pipelines on the input end side of the first water pump, so as to supplement liquid and exhaust in the refrigerant in the first circulating pipeline.

[0041] The utility model provides a kind of for multi-circuit liquid cooling system of liquid cooling unit, battery and converter are arranged in the both ends of the first heat exchanger of refrigeration device in parallel, by the first heat exchanger of refrigeration device respectively through first circulation pipeline and second circulation pipeline heat exchange is carried out to battery and converter, and different refrigerant temperature is provided by electric valve and three-way regulating valve distribution flow.In low ambient temperature, refrigeration device is closed, air cooling radiator passes through fourth circulation pipeline and fifth circulation pipeline, utilize natural cold source to cool battery and converter, greatly improve system energy efficiency.When battery does not run, and cell temperature is too low, open pipeline heater to heat battery, and heat battery and converter by first circulation pipeline and second circulation pipeline.It solves the cooling of existing liquid cooling unit to battery and converter without grading, there is energy consumption, the problem of not energy saving, can improve the annual comprehensive energy efficiency of liquid cooling unit, reduce energy consumption. BRIEF DESCRIPTION OF DRAWINGS

[0042] In order to more clearly illustrate the specific embodiments of the utility model, the following will be needed to use the drawings in the embodiment briefly introduced.

[0043] Figure 1 It is a kind of for the schematic diagram of multi-circuit liquid cooling system of liquid cooling unit provided by the utility model.

[0044] Figure 2 It is the schematic diagram of another kind of for the multi-circuit liquid cooling system of liquid cooling unit provided by the utility model embodiment. DETAILED DESCRIPTION

[0045] In order to make the personnel in this technical field better understand the scheme of the utility model embodiment, the following will be further detailed to the utility model embodiment by combining with drawing and implementation.

[0046] For the cooling and heating of current liquid cooling unit to battery and converter, the utility model provides a kind of for multi-circuit liquid cooling system of liquid cooling unit, solves the cooling of existing liquid cooling unit to battery and converter without grading, there is energy consumption, the problem of not energy saving, can improve the annual comprehensive energy efficiency of liquid cooling unit, reduce energy consumption.

[0047] As Figure 1 And Figure 2As shown, a multi-loop liquid cooling system for a liquid cooling unit includes a refrigeration device, a first water pump P1, an electric valve V5, and a three-way regulating valve V6. The battery and the converter PCS are arranged in parallel with the first heat exchanger of the refrigeration device; the first heat exchanger of the refrigeration device is connected to the cold plate circuit of the battery through a first circulating pipeline S1, and is connected to the cold plate circuit of the converter through a second circulating pipeline S2; the first water pump P1 is connected in series between the cold plate of the battery and the first heat exchanger 1, and the output end of the first water pump P1 is also connected to one end of the electric valve V5; the first input end and the output end of the three-way regulating valve V6 are connected in series between the cold plate of the converter and the first heat exchanger 1, and the second input end of the three-way regulating valve V6 is also connected to the other end of the electric valve V5; the three-way regulating valve V6 is used to adjust the flow rate ratio of the inlet refrigerant liquid to adjust the temperature of the refrigerant liquid of the cold plate of the converter. When the ambient temperature is greater than a first temperature threshold, the first water pump P1 operates, and the refrigeration device provides different refrigerant liquid temperatures to the battery and the converter through the first circulating pipeline S1 and the second circulating pipeline S2 respectively to perform staged refrigeration heat exchange.

[0048] Specifically, the refrigeration device is classified according to the circulating medium and can be divided into a fluorine system and a refrigerant liquid system. The refrigeration device is provided with a first heat exchanger. The refrigerant of the fluorine system exchanges heat with the refrigerant liquid system through the first heat exchanger. The first heat exchanger is provided with a refrigerant liquid side and a refrigerant side. The refrigerant liquid side of the first heat exchanger is connected to the cold plate circuit of the battery through a first circulating pipeline and is connected to the cold plate circuit of the converter through a second circulating pipeline. The refrigerant side of the first heat exchanger is arranged on the refrigerant circulating pipeline of the refrigeration device. The refrigerant liquid on the refrigerant liquid side exchanges heat with the refrigerant on the refrigerant side to refrigerate the refrigerant liquid on the refrigerant liquid side. The refrigerant liquid in the first circulating pipeline returns to the first water pump P1 after passing through the first water pump P1, the refrigerant liquid side of the first heat exchanger 1, and the cold plate of the battery, so that the first heat exchanger 1 forms a refrigeration circulating loop for the cold plate of the battery. The refrigerant liquid in the second circulating pipeline is divided into two paths after passing through the first water pump P1. One path enters the second input end of the three-way regulating valve V6 through the electric valve V5, and the other path enters the first input end of the three-way regulating valve V6 after being cooled by the refrigerant liquid side of the first heat exchanger. The three-way regulating valve V6 adjusts the opening degree of the first input end and the second input end to adjust the flow rate ratio of the inlet refrigerant liquid. The refrigerant liquid cooled by the battery is mixed with the refrigerant liquid re-cooled by the refrigerant liquid side of the first heat exchanger through the electric valve V5, and then enters the cold plate of the PCS through the output end of the three-way regulating valve V6. Finally, the refrigerant liquid is mixed with the cooling liquid from the cold plate of the battery and returns to the first water pump P1. The electric valve V5 can also adjust the flow rate of the refrigerant liquid, and together with the three-way regulating valve V6, the temperature of the refrigerant liquid is adjusted, so that the refrigerant liquid temperature for the battery is 15-22℃, and the refrigerant liquid temperature for the PCS is 40-50℃, to achieve staged refrigeration.

[0049] In practical application, when the ambient temperature is high, generally the ring temperature is greater than 10℃, the refrigeration device is operated to refrigerate, and the battery cell and the PCS are refrigerated and heat-exchanged through the first circulating pipeline and the second circulating pipeline. This method distributes the flow through the electric valve and the three-way regulating valve to provide different refrigerant temperatures, and provides different cooling medium temperatures for battery cooling and inverter cooling, which can solve the problem that the existing liquid cooling unit does not have a grading for battery and inverter cooling, and has a large energy consumption and is not energy-saving, and can improve the annual comprehensive energy efficiency of the liquid cooling unit and reduce energy consumption.

[0050] Further, the system further comprises: an air-cooled radiator; one end of the air-cooled radiator is connected with the output end of the first water pump, and the other end of the air-cooled radiator is connected with the first input end of the three-way regulating valve and the cold plate of the battery respectively; when the ambient temperature is less than a second temperature threshold, the refrigeration device is not started, and the first water pump is operated to refrigerate and heat-exchange the battery and the inverter through the air-cooled radiator, wherein the second temperature threshold is less than the first temperature threshold.

[0051] In practical application, an exhaust fan can be arranged on the air-cooled radiator to improve the heat dissipation efficiency. When the ambient temperature is low, generally less than 10℃, the fluorine system of the refrigeration device is not started, and in order to cool the battery cell and the PCS, the natural cooling can be directly used, and the refrigerant of the battery cell and the PCS is heat-exchanged by the air-cooled radiator. At this time, the external environment air temperature is relatively low, which meets the refrigeration requirement. The air-cooled radiator can be a cooling tower structure to reduce energy consumption.

[0052] Further, the refrigeration device further comprises: a compressor, an expansion valve Z1, a second heat exchanger 2 and a liquid accumulator; the first heat exchanger 1, the compressor, the second heat exchanger 2, the liquid accumulator and the expansion valve Z1 are sequentially arranged on the refrigerant circulating pipeline, the first heat exchanger 1 serves as an evaporator, and the second heat exchanger 2 serves as a condenser. When the compressor is operated, the refrigerant is heat-absorbed and refrigerated by the first heat exchanger 1, and is liquefied and heat-released by the second heat exchanger 2.

[0053] Specifically, when the compressor of the refrigeration device is running, the refrigerant is warmed and pressurized, then releases heat through the condenser, and is condensed into high-pressure liquid. Then, the high-pressure liquid is depressurized through the expansion valve, enters the evaporator, absorbs heat in the evaporator, evaporates into low-temperature and low-pressure steam, is sucked into the compressor again, and starts a new cycle. In this embodiment, the first heat exchanger can be directly used as the evaporator of the refrigeration device, and the refrigeration device cools externally through the first heat exchanger. When the ambient temperature is high, the compressor is started, and the fluorine system of the refrigeration device is operated, and the refrigerant circulates through the compressor, the second heat exchanger 2, the liquid accumulator, the expansion valve Z1, the first heat exchanger 1 and the compressor in turn. The first heat exchanger 1 is an evaporator, and the cold energy generated by the evaporator is transferred to the refrigerant side to exchange heat with the refrigerant flowing therethrough.

[0054] Further, the refrigerant side of the second heat exchanger 2 is connected to the air-cooled radiator circuit through a third circulation circuit S3, so that the second heat exchanger 2 exchanges heat with the outside through the air-cooled radiator.

[0055] The system further comprises a second water pump P2; the second water pump P2 is arranged on the third circulation circuit S3, and the second water pump P2 is connected in series between the air-cooled radiator and the second heat exchanger. When the second water pump P2 is running, the refrigerant in the third circulation circuit S3 is driven to circulate, so that the air-cooled radiator takes away the heat discharged by the second heat exchanger.

[0056] In actual application, when the ambient temperature is high, the refrigeration device is started, the compressor is running, the first heat exchanger 1 exchanges heat with the outside through the first circulation circuit S1 and the second circulation circuit S2, and the heat generated by the second heat exchanger 2 is exchanged with the air-cooled radiator through the third circulation circuit S3. The traditional refrigerant and air heat exchange is converted into refrigerant first heat exchange with refrigerant, and finally the refrigerant is exchanged with the radiator to the outside, so that the heat exchange efficiency of the system is improved. The second heat exchanger can be arranged outside the liquid cooling unit, such as arranged to the battery cabinet, or the air-cooled radiator and the second heat exchanger can be arranged at the top of the box body and the like to improve the heat exchange efficiency.

[0057] The system further comprises a pipeline heater; the pipeline heater is arranged on the first circulation circuit S1 and connected in series between the refrigerant output end of the first heat exchanger 1 and the input end of the cold plate of the battery; when the temperature of the battery cell is less than a third temperature threshold, the pipeline heater is used to heat and warm the refrigerant in the first circulation circuit S1, so that the refrigerant temperature of the cold plate of the battery is within a set range, wherein the third temperature threshold is less than 14℃.

[0058] In practical applications, the battery is in a non-running state, and the working performance of the battery cell will decrease when the cell temperature is lower than a third temperature threshold, which is determined by the start heating temperature and can be in the range of -20 to 14℃. Therefore, the battery cell needs to be heated to raise its temperature to a set range. By setting a pipe heater to warm the refrigerant in the first circulating pipe, the temperature of the cold plate of the main battery is raised to achieve cell heating.

[0059] Further, the first heat exchanger 1 and the second heat exchanger 2 are both plate heat exchangers. Specifically, the evaporator and condenser of the fluorine cycle in the refrigeration device are both plate heat exchangers, which can be arranged inside the box body, making the structure more compact and facilitating modularization. At the same time, the refrigerant side and the refrigerant side of the first heat exchanger and the second heat exchanger can be connected through corresponding pipes to realize heat exchange.

[0060] In an embodiment, in order to realize the switching of the multi-loop liquid cooling pipeline, as shown in Figure 1 The first electromagnetic valve K1 is connected in series between the output end of the first water pump P1 and the refrigerant input end of the first heat exchanger 1, and the first electromagnetic valve K1 is used to control the conduction or shutdown of the pipeline between the output end of the first water pump and the first heat exchanger 1.

[0061] The second electromagnetic valve K2 is connected in series between the output end of the first water pump P1 and the air-cooled radiator, and the second electromagnetic valve K2 is used to control the conduction or shutdown of the pipeline between the first water pump P1 and the air-cooled radiator.

[0062] The third electromagnetic valve K3 is connected in series between the refrigerant output end of the second heat exchanger 2 and the air-cooled radiator, and the third electromagnetic valve K3 is used to control the conduction or shutdown of the pipeline between the refrigerant output end of the second heat exchanger and the air-cooled radiator.

[0063] The fourth electromagnetic valve K4 is connected in series between the refrigerant output end of the first heat exchanger 1 and the refrigerant output end of the second heat exchanger, and the fourth electromagnetic valve is used to control the conduction or shutdown of the pipeline between the refrigerant output end of the first heat exchanger and the refrigerant input end of the second heat exchanger.

[0064] When the ambient temperature is greater than the first temperature threshold and the refrigeration device is started, the second electromagnetic valve K2 and the fourth electromagnetic valve K4 are both closed, so that the first water pump P1 drives the refrigerant in the first circulating pipeline S1 and the second circulating pipeline S2 to circulate, and the refrigerant in the third circulating pipeline S3 is circulated by the second water pump P2.

[0065] At this time, the first circulation pipeline S1 is connected in sequence with the first water pump P1, the first electromagnetic valve K1, the first heat exchanger 1, the pipeline heater, the battery cold plate, and the water pump P1; the second circulation pipeline S2 is connected in sequence with the first water pump P1, the electric valve V5, the three-way regulating valve V6, the inverter cold plate, and the first water pump P1. The coolant is divided into two paths by the first water pump P1, one path goes to cool the battery cells, respectively passes through the electromagnetic valve K1, the first heat exchanger 1, the pipeline heater, and the battery cold plate, and finally mixes with the coolant from the PCS and returns to the first water pump P1. The other path goes through the electric valve V5 from the first water pump P1, mixes with the low-temperature coolant from the three-way regulating valve V6, enters the PCS cold plate to cool the PCS, mixes with the coolant from the battery cells, and returns to the first water pump P1, to provide different water temperatures for the battery cell cooling and the PCS cooling. At the same time, the second electromagnetic valve K2 and the fourth electromagnetic valve K4 are closed, so that the third circulation loop is not connected with the coolant of the first circulation loop. The third circulation pipeline S3 is connected in sequence with the air-cooled radiator, the second water pump P2, the second heat exchanger 2, the third electromagnetic valve K3, and the air-cooled radiator. At this time, the second water pump P2 operates, and the coolant passes through the second water pump P2, the second heat exchanger 2, the third electromagnetic valve K3, and the air-cooled radiator in sequence, and finally returns to the second water pump P2, to realize that the exhaust heat of the second heat exchanger 2 is taken away by the air-cooled radiator.

[0066] When the ambient temperature is less than the second temperature threshold and the refrigeration device is not started, the first electromagnetic valve K1 and the third electromagnetic valve K3 are closed, and the second electromagnetic valve K2 and the fourth electromagnetic valve K4 are opened, so that the air-cooled radiator cools and exchanges heat with the battery and the inverter.

[0067] At this time, the ambient temperature is low, the refrigeration device is closed, and the first electromagnetic valve K1 and the third electromagnetic valve K3 are closed, so that the coolant of the first heat exchanger does not enter the first circulation pipeline and the second circulation pipeline, and directly cools the battery cells and the PCS by natural cooling. The air-cooled radiator cools the battery cells through the fourth circulation pipeline and cools the inverter through the fifth circulation pipeline. The fourth circulation pipeline is connected in sequence with the first water pump P1, the second electromagnetic valve K2, the air-cooled radiator, the fourth electromagnetic valve K4, the pipeline heater, the battery cold plate, and the first water pump P1; the fifth circulation pipeline is connected in sequence with the first water pump P1, the second electromagnetic valve K2, the air-cooled radiator, the fourth electromagnetic valve K4, the three-way regulating valve V6, the inverter cold plate, and the first water pump P1. Therefore, through the cooperation of the first electromagnetic valve, the second electromagnetic valve, the third electromagnetic valve, and the fourth electromagnetic valve, the mutual switching of multiple loops is realized, the temperature of the coolant of the battery and the inverter is adjusted, the refrigeration device is closed at low ambient temperature, the air-cooled radiator utilizes the natural cooling source, and the battery and the inverter are cooled through the fourth circulation pipeline and the fifth circulation pipeline, which greatly improves the energy efficiency of the system.

[0068] In another embodiment, in order to realize the switching of the multi-loop liquid cooling pipeline, as shown in Figure 2 The system further comprises a first electric three-way valve V1, a second electric three-way valve V2, a third electric three-way valve V3, and a fourth electric three-way valve V4. The first end of the first electric three-way valve V1 is connected with the output end of the first water pump P1, the second end of the first electric three-way valve V1 is connected with the refrigerant input end of the first heat exchanger 1, and the third end of the first electric three-way valve V1 is connected with the first port of the second electric three-way valve V2.

[0069] The second port of the second electric three-way valve V2 is connected with the refrigerant output end of the second heat exchanger 2, and the third port of the second electric three-way valve V2 is connected with one end of the air-cooled radiator.

[0070] The first port of the third electric three-way valve V3 is connected with one end of the pipeline heater, the second port of the third electric three-way valve V3 is connected with the refrigerant output end of the first heat exchanger 1 and the first input end of the three-way regulating valve V6 respectively, and the third port of the third electric three-way valve V3 is connected with the first port of the fourth electric three-way valve V4.

[0071] The second port of the fourth electric three-way valve V4 is connected with the input end of the second water pump P2, and the third port of the fourth electric three-way valve V4 is connected with the other end of the air-cooled radiator.

[0072] When the ambient temperature is greater than the first temperature threshold value and the refrigeration device is started, the pipeline flow between the first electric three-way valve V1 and the second electric three-way valve V2 is closed, the pipeline flow between the third electric three-way valve V3 and the fourth electric three-way valve V4 is closed, the first heat exchanger 1 exchanges heat with the battery and the inverter through the first circulation pipeline S1 and the second circulation pipeline S2, and the second heat exchanger 2 exchanges heat with the air-cooled radiator through the third circulation pipeline S3.

[0073] When the ambient temperature is less than the second temperature threshold value and the refrigeration device is not started, the pipeline flow between the first electric three-way valve V1 and the third electric three-way valve V3 is closed, the pipeline flow between the second electric three-way valve V2 and the fourth electric three-way valve V4 is closed, and the air-cooled radiator exchanges heat with the battery and the inverter.

[0074] In actual application, the first electric three-way valve, the second electric three-way valve, the third electric three-way valve, and the fourth electric three-way valve can be adjusted by controlling the opening degree of the corresponding port to realize the automatic control of the on-off of each port.

[0075] The system further comprises an expansion tank and a liquid supplement tank; the expansion tank and the liquid supplement tank are arranged on the corresponding pipelines on the input side of the first water pump to supplement liquid and exhaust air in the refrigerant in the first circulating pipeline.

[0076] In practical application, as shown in Figure 1 and Figure 2 shown, the liquid cooling unit needs to be provided with a liquid supplement tank and an expansion tank in the circulating pipeline to supplement liquid and exhaust air in the refrigerant in the circulating pipeline; the liquid supplement tank supplements the refrigerant in the circulating pipeline through a liquid supplement pipeline, and the liquid supplement pipeline is provided with a liquid supplement pump P3 and a one-way valve. Meanwhile, an automatic exhaust valve is arranged in the refrigerant pipeline of the battery to discharge the gas in the circulating pipeline in real time, thereby increasing the refrigeration effect.

[0077] It can be seen that the utility model provides a multi-loop liquid cooling system for a liquid cooling unit; the battery and the converter are arranged in parallel at both ends of the first heat exchanger of the refrigeration device, the battery and the converter are heat-exchanged by the first heat exchanger of the refrigeration device through the first circulating pipeline and the second circulating pipeline respectively, and the flow is distributed through the electric valve and the three-way regulating valve to provide different refrigerant temperatures. In a low ambient temperature, the refrigeration device is closed, the air cooling radiator cools the battery and the converter through the fourth circulating pipeline and the fifth circulating pipeline, and a natural cold source is used to cool the battery and the converter, thereby greatly improving the system energy efficiency. When the battery is not running and the battery cell temperature is too low, the pipeline heater is started to heat the battery, and the battery and the converter are heated through the first circulating pipeline and the second circulating pipeline. The utility model solves the problem that the existing liquid cooling unit does not have a grading for cooling the battery and the converter, and the energy consumption is large and not energy-saving, thereby improving the annual comprehensive energy efficiency of the liquid cooling unit and reducing the energy consumption.

[0078] The above describes the structure, features and effect of the utility model according to the embodiment shown in the drawing, and the above is only a preferred embodiment of the utility model, but the utility model is not limited to the embodiment shown in the drawing, any change or modification made according to the concept of the utility model, or the equivalent embodiment with equivalent changes, as long as it is within the scope of the utility model, should be within the protection scope of the utility model.

Claims

1. A multi-loop liquid cooling system for a liquid-cooled unit, characterized in that, The application relates to a refrigeration device, a first water pump, an electric valve and a three-way regulating valve. A battery and a converter are arranged in parallel with two ends of a first heat exchanger in the refrigeration device. The first heat exchanger is connected with a cold plate pipeline of the battery through a first circulating pipeline, and the first heat exchanger is connected with a cold plate pipeline of the converter through a second circulating pipeline. The first water pump is connected in series between the cold plate of the battery and the first heat exchanger, and an output end of the first water pump is also connected with one end of the electric valve. First and second input ends of the three-way regulating valve are connected in series between the cold plate of the converter and the first heat exchanger, and the second input end of the three-way regulating valve is also connected with the other end of the electric valve. The three-way regulating valve is used for adjusting the refrigerant flow ratio of the inlet to adjust the refrigerant temperature of the cold plate of the converter. When the ambient temperature is greater than a first temperature threshold, the first water pump operates, and the refrigeration device provides different refrigerant temperatures for the battery and the converter through the first and second circulating pipelines respectively to perform staged refrigeration heat exchange. Further comprising:

2. The multi-loop liquid cooling system for liquid cooled server units according to claim 1, wherein, An air-cooled radiator; One end of the air-cooled radiator is connected with the output end of the first water pump, and the other end of the air-cooled radiator is connected with the first input end of the three-way regulating valve and the cold plate of the battery respectively. When the ambient temperature is less than a second temperature threshold, the refrigeration device is not started, and the first water pump operates to perform staged refrigeration heat exchange on the battery and the converter through the air-cooled radiator, wherein the second temperature threshold is less than the first temperature threshold. The refrigeration device further comprises a compressor, an expansion valve, a second heat exchanger and a liquid accumulator.

3. The multi-loop liquid cooling system for liquid cooled server units of claim 2, wherein, The first heat exchanger, the compressor, the second heat exchanger, the liquid accumulator and the expansion valve are sequentially arranged on a refrigerant circulating pipeline, the first heat exchanger serves as an evaporator, the second heat exchanger serves as a condenser, and when the compressor operates, the refrigerant is subjected to heat absorption refrigeration through the first heat exchanger and is subjected to liquefaction heat release through the second heat exchanger. The refrigerant side of the second heat exchanger is connected with the air-cooled radiator pipeline through a third circulating pipeline, so that the second heat exchanger exchanges heat with the outside through the air-cooled radiator.

4. The multi-loop liquid cooling system for liquid cooled server units of claim 3, wherein, Further comprising:

5. The multi-loop liquid cooling system for liquid-cooled units according to claim 4, characterized in that, A second water pump; The second water pump is arranged on the third circulating pipeline and is connected in series between the air-cooled radiator and the second heat exchanger, and when the second water pump operates, the refrigerant in the third circulating pipeline is driven to circulate, so that the air-cooled radiator carries away the heat discharged by the second heat exchanger. Further comprising:

6. The multi-loop liquid cooling system for liquid cooled units according to claim 5, wherein, A pipeline heater; The pipeline heater is arranged on the first circulating pipeline and is connected in series between the refrigerant output end of the first heat exchanger and the input end of the cold plate of the battery. When the temperature of the battery cell is less than a third temperature threshold, the pipeline heater is used for heating and warming the refrigerant in the first circulating pipeline, so that the refrigerant temperature of the cold plate of the battery is within a set range, and the third temperature threshold is less than 14 DEG C. The first heat exchanger and the second heat exchanger are both plate heat exchangers.

7. The multi-loop liquid cooling system for liquid cooled server units of claim 6, wherein, Further comprising:

8. The multi-loop liquid cooling system for liquid cooled server units of claim 7, wherein, A first electromagnetic valve, a second electromagnetic valve, a third electromagnetic valve and a fourth electromagnetic valve; ​ The first electromagnetic valve is connected in series between the output end of the first water pump and the refrigerant input end of the first heat exchanger; The second electromagnetic valve is connected in series between the output end of the first water pump and the air-cooled radiator; The third electromagnetic valve is connected in series between the refrigerant output end of the second heat exchanger and the air-cooled radiator; The fourth electromagnetic valve is connected in series between the refrigerant output end of the first heat exchanger and the refrigerant output end of the second heat exchanger; When the ambient temperature is greater than the first temperature threshold and the refrigeration device is started, the second electromagnetic valve and the fourth electromagnetic valve are turned off, so that the first water pump drives the refrigerant in the first circulation pipeline and the second circulation pipeline to circulate, and the third circulation pipeline is driven by the second water pump to circulate; When the ambient temperature is less than the second temperature threshold and the refrigeration device is not started, the first electromagnetic valve and the third electromagnetic valve are turned off, and the second electromagnetic valve and the fourth electromagnetic valve are turned on, so that the air-cooled radiator cools and exchanges heat with the battery and the inverter.

9. The multi-loop liquid cooling system for liquid cooled server units of claim 7, wherein, Further comprising: A first electric three-way valve, a second electric three-way valve, a third electric three-way valve and a fourth electric three-way valve; The first end of the first electric three-way valve is connected with the output end of the first water pump, the second end of the first electric three-way valve is connected with the refrigerant input end of the first heat exchanger, and the third end of the first electric three-way valve is connected with the first port of the second electric three-way valve; The second port of the second electric three-way valve is connected with the refrigerant output end of the second heat exchanger, and the third port of the second electric three-way valve is connected with one end of the air-cooled radiator; The first port of the third electric three-way valve is connected with one end of the pipe heater, the second port of the third electric three-way valve is connected with the refrigerant output end of the first heat exchanger and the first input end of the three-way regulating valve respectively, and the third port of the third electric three-way valve is connected with the first port of the fourth electric three-way valve; The second port of the fourth electric three-way valve is connected with the input end of the second water pump, and the third port of the fourth electric three-way valve is connected with the other end of the air-cooled radiator; When the ambient temperature is greater than the first temperature threshold and the refrigeration device is started, the pipeline flow between the first electric three-way valve and the second electric three-way valve is turned off, and the pipeline flow between the third electric three-way valve and the fourth electric three-way valve is turned off, so that the first heat exchanger cools and exchanges heat with the battery and the inverter through the first circulation pipeline and the second circulation pipeline, and the second heat exchanger exchanges heat with the air-cooled radiator through the third circulation pipeline; When the ambient temperature is less than the second temperature threshold and the refrigeration device is not started, the pipeline flow between the first electric three-way valve and the third electric three-way valve is turned off, and the pipeline flow between the second electric three-way valve and the fourth electric three-way valve is turned off, so that the air-cooled radiator cools and exchanges heat with the battery and the inverter.

10. The multi-loop liquid cooling system for liquid-cooled units according to claim 8 or 9, characterized in that, Further comprising: An expansion tank and a liquid supplement tank; The expansion tank and the liquid supplement tank are arranged on the corresponding pipelines on the input side of the first water pump to supplement liquid and exhaust air in the refrigerant in the first circulating pipeline.

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