A direct cooling heat pump air conditioning system for energy storage temperature control system

Abstract

The application provides a direct-cooling heat pump air conditioning system for an energy storage temperature control system, which comprises a compressor, a four-way valve, a first branch, a second branch and a liquid cooling device, the first branch is provided with a first end and a second end, the second branch is provided with port A and port B, the second end and port B are connected to two ends of the liquid cooling device respectively; the four-way valve is provided with a first valve port, a second valve port, a third valve port and a fourth valve port, the exhaust port of the compressor is communicated with the first valve port, the suction port of the compressor is communicated with the third valve port, the first end is communicated with the second valve port, and port A is communicated with the fourth valve port; the first branch is serially connected with a first condensing section and a first heat exchange section, the first heat exchange section is arranged between the first condensing section and the second end; the second branch is serially connected with a second condensing section and a second heat exchange section, and the second heat exchange section is arranged between the second condensing section and port B. The application solves the technical problem that the liquid cooling system in the prior art needs multiple heat exchanges and cannot directly apply cold energy to the heating battery cell, thereby causing low heat exchange performance.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of air conditioning, in particular to a direct-cooling heat pump air conditioning system for an energy storage temperature control system. BACKGROUND

[0002] With the rise of the new energy industry, lithium batteries as energy storage devices can extend their service life and increase the safety of the unit in an excellent charging and discharging environment. Therefore, energy storage air conditioners have an excellent reputation in the new energy industry and provide stable working temperature for battery units.

[0003] The temperature control units on the market at present are mainly liquid-cooled and air-cooled energy storage air conditioners. The liquid-cooled air conditioner with 50% ethylene glycol aqueous solution as the coolant has higher heat exchange performance and energy efficiency than the air-cooled air conditioner. However, from the heat exchange principle, the heat emitted by the battery is exchanged with the ethylene glycol aqueous solution in the cold plate, and the heat needs to be exchanged again through the plate heat exchanger of the energy storage air conditioner. At this time, the heat can be received and digested by the fluorine system. As can be seen, the liquid cooling system in the prior art needs multiple heat exchanges, which cannot directly apply cold energy to the heating battery cells, resulting in low heat exchange performance. SUMMARY

[0004] The present application solves the technical problem of low heat exchange performance caused by the need for multiple heat exchanges in the liquid cooling system in the prior art, which cannot directly apply cold energy to the heating battery cells.

[0005] To solve the above problems, the present application provides a direct-cooling heat pump air conditioning system for an energy storage temperature control system, comprising: a compressor, a four-way valve, a first branch, a second branch and a liquid cooling device, the first branch is provided with a first end and a second end, the second branch is provided with a port A and a port B, and the second end and the port B are respectively connected to two ends of the liquid cooling device; the four-way valve is provided with a first valve port, a second valve port, a third valve port and a fourth valve port, and the exhaust port of the compressor and the first valve port are communicated, the suction port of the compressor and the third valve port are communicated, the first end and the second valve port are communicated, and the port A and the fourth valve port are communicated; a first condensing section and a first heat exchange section are connected in series on the first branch, and the first heat exchange section is arranged between the first condensing section and the second end; a second condensing section and a second heat exchange section are connected in series on the second branch, and the second heat exchange section is arranged between the second condensing section and the port B.

[0006] Compared with the prior art, the technical effects achieved by the technical scheme are as follows: the first valve port is communicated with the exhaust port of the compressor, the third valve port is communicated with the suction port of the compressor, the second valve port and the fourth valve port are respectively communicated with the first branch and the second branch, under different operating states of the direct-cooling heat pump air conditioning system, the flow direction of the refrigerant flowing out of the exhaust port of the compressor is controlled by controlling the operating state of the four-way valve, so as to control the flow direction of the refrigerant. One end of the liquid cooling device is connected to the second end of the first branch, and the other end is connected to the port B of the second branch, so that the liquid cooling device can directly exchange heat in the fluorine system, the heat of the battery in the liquid cooling device directly acts on the fluorine system to be received and released, and the heat exchange performance and energy efficiency are improved. That is, the water pump, the expansion tank and the water circuit thereof are removed, the refrigerant is directly used for heat exchange, one-time heat exchange is realized, energy consumption is reduced, and energy efficiency is improved. The direct-cooling heat pump air conditioning system further comprises a first condensing section and a second condensing section. Specifically, the structure of the first condensing section and the second condensing section is realized by arranging a double-flow channel, a branch and a valve in the condenser. The direct-cooling heat pump air conditioning system further comprises a first heat exchange section and a second heat exchange section. Specifically, the structure of the first heat exchange section and the second heat exchange section is realized by arranging a plate heat exchanger. The condensation of the refrigerant in the system and the heat exchange effect are controlled by controlling the on-off of the first condensing section, the second condensing section, the first heat exchange section and the second heat exchange section.

[0007] In an example of the present application, the number of liquid cooling devices is multiple, and the multiple liquid cooling devices are arranged in parallel.

[0008] Compared with the prior art, the technical effects achieved by the technical scheme are as follows: the multiple liquid cooling devices can control the flow of the refrigerant flowing into each liquid cooling device according to actual needs, so as to meet the heat exchange effect of the refrigerant flowing through the liquid cooling device under specific conditions. The first-level distribution of the refrigerant can be realized by the on-off of each liquid cooling device.

[0009] In an example of the present application, the liquid cooling device comprises a liquid cooling throttling element, a liquid distributor and multiple liquid cooling components. The liquid cooling throttling element is connected to the second end, the liquid cooling components are connected to the port B, and the liquid distributor is connected between the liquid cooling throttling element and the liquid cooling components. The multiple liquid cooling components are arranged in parallel.

[0010] Compared with the prior art, the technical effects achieved by the technical scheme are as follows: because the refrigerant distribution is uneven and the flow through each liquid cooling component is different in the prior art, the liquid distribution is designed in the present application, the liquid cooling components are supplied with liquid by the liquid distributor, the uniform distribution of the refrigerant is realized, the refrigerant flowing to the liquid cooling device can uniformly flow to the multiple liquid cooling components, the liquid cooling throttling element is arranged, the throttling of the refrigerant is realized by the liquid cooling throttling element, the pressure reduction and the first-level liquid distribution are realized at the same time, and the state of the refrigerant is realized to flash to change the evaporation temperature.

[0011] In an example of the present application, the direct-cooling heat pump air conditioning system further comprises: a first valve connected in parallel to both ends of the first heat exchange section; a first throttling element connected in parallel to both ends of the second heat exchange section; and a second throttling element connected in series to the first branch, and arranged between the first heat exchange section and the second end.

[0012] Compared with the prior art, the technical effects achieved by the technical scheme are as follows: the first valve is connected in parallel to both ends of the first heat exchange section, and when the refrigerant flowing through the first branch and the refrigerant flowing through the second branch does not need to exchange heat (at this time, the refrigerant does not need to pass through the first heat exchange section), the first valve is opened, so that the refrigerant flowing through the first branch passes through the first valve, thereby avoiding the refrigerant from flowing through the first heat exchange section; the first throttling element is connected in parallel to both ends of the second heat exchange section, and the first throttling element is opened as needed, so as to ensure that the refrigerant at the outlet of the second heat exchange section is in a required state; and the second throttling element is used for throttling and pressure reduction.

[0013] In an example of the present application, the direct-cooling heat pump air conditioning system further comprises: a second valve, one end of the second valve being connected to the first branch between the second throttling element and the second end, and the other end of the second valve being connected to the second branch between the second heat exchange section and the port B.

[0014] Compared with the prior art, the technical effects achieved by the technical scheme are as follows: the two ends of the second valve are connected to the two ends of the liquid cooling device, and by controlling the on-off of the second valve and the liquid cooling throttling element, whether the refrigerant flows through the liquid cooling device can be controlled; when the second valve is opened and the opening degree of the liquid cooling throttling element in each liquid cooling device is 0 pls, the refrigerant flowing out of the outlet of the first heat exchange section does not flow through the liquid cooling device, but directly flows to the second heat exchange section through the second valve.

[0015] In an example of the present application, the direct-cooling heat pump air conditioning system further comprises: a third valve arranged on the second branch, and arranged between the second condensing section and the second heat exchange section; and a fourth valve connected in parallel to the second branch, one end of the fourth valve being connected to between the port A and the second condensing section, and the other end of the fourth valve being connected to between the third valve and the second heat exchange section.

[0016] Compared with the prior art, the technical effects achieved by the technical scheme are as follows: by arranging the third valve and the fourth valve, the flow direction of the refrigerant discharged from the outlet of the compressor after flowing through the four-way valve to the second branch can be controlled; when the third valve is opened and the fourth valve is closed, the refrigerant flowing through the second branch flows through the third valve and the second condensing section; when the third valve is closed and the fourth valve is opened, the refrigerant flowing through the second branch does not flow through the third valve and the second condensing section, but directly connects the four-way valve through the fourth valve.

[0017] In one example of the present application, the direct-cooling heat pump air conditioning system further comprises a heating device, the heating device being connected between the suction port and the third valve port.

[0018] Compared with the prior art, the technical effects achieved by adopting the technical scheme are as follows: when the system receives defrosting instructions during the heating operation of the direct-cooling heat pump air conditioning system, the present application can realize defrosting by setting the heating device, thereby avoiding affecting the running battery.

[0019] In one example of the present application, the direct-cooling heat pump air conditioning system further comprises an oil separator, the oil separator being connected between the exhaust port and the first valve port; and a gas-liquid separator, the gas-liquid separator being connected between the suction port and the heating device.

[0020] Compared with the prior art, the technical effects achieved by adopting the technical scheme are as follows: the oil separator is used to separate the gas and oil of the direct-cooling heat pump air conditioning system, specifically, the oil separator separates the compressor oil in the high-temperature and high-pressure steam discharged by the compressor, thereby ensuring the reliability of the compressor and ensuring the safe and efficient operation of the multi-split system; since the compressor can only compress gas, if the compressor "returns liquid", the compressor is prone to damage, therefore, the gas-liquid separator for separating gas and liquid is added in the direct-cooling heat pump air conditioning system, if the refrigerant is not completely evaporated, the gas-liquid mixed refrigerant can first flow back to the gas-liquid separator and separate the gas therefrom, so that the separated gas flows back to the compressor, and the separated liquid remains in the gas-liquid separator, thereby buffering the gas-liquid separator.

[0021] In one example of the present application, the direct-cooling heat pump air conditioning system further comprises a bypass pipeline, one end of the bypass pipeline being connected to the oil separator, and the other end of the bypass pipeline being connected to the suction port; and a third filter, the third filter being connected in series to the bypass pipeline.

[0022] Compared with the prior art, the technical effects achieved by adopting the technical scheme are as follows: a small amount of compressor oil is brought out by the high-temperature and high-pressure steam refrigerant compressed by the compressor, after flowing through the oil separator, the gas and oil are separated due to the special structure thereof, the oil flows to the bottom of the oil separator under the influence of gravity, and the oil flows through the third filter and the capillary tube of the bypass pipeline under the suction force of the compressor, and then returns to the compressor.

[0023] In one example of the present application, the direct-cooling heat pump air conditioning system further comprises a condenser, the condenser being provided with a first condensing section and a second condensing section; and a plate heat exchanger, the plate heat exchanger being provided with a first heat exchanging section and a second heat exchanging section.

[0024] Compared with the prior art, the technical effects achieved by adopting the technical scheme are: the structure of the first condensing section and the second condensing section is realized through the condenser, so that the overall structure of the direct-cooling heat pump air conditioning system is more simple, and specifically: the double flow channels, the small branch and the bypass design of the condenser are designed to meet the temperature drop of the high-temperature gaseous refrigerant during normal heating, so that the temperature of the refrigerant entering the cold plate is not more than 35 DEG C, and the battery works in the best working range of 20-30 DEG C; during ultra-low temperature heating (i.e. adverse condition heating), the outer ring temperature is low, and if the condenser branch is used for temperature reduction, condensation is easy, so the plate heat exchanger is combined to realize heat exchange by using the temperature difference between the evaporation and condensation ends, and the exhaust gas temperature reduction is realized; the structure of the first heat exchange section and the second heat exchange section is realized through the plate heat exchanger, so that the refrigerant flowing through the first heat exchange section and the second heat exchange section realizes heat exchange through the plate heat exchanger. In the present application, uniform temperature design is performed, the cold plate is not overheated, the heat exchange outlet is gas-liquid mixture, and overheat is realized by using the plate heat exchanger and pipeline design.

[0025] After adopting the technical scheme of the present application, the following technical effects can be achieved:

[0026] (1) One end of the liquid cooling device is connected to the second end of the first branch, and the other end is connected to the port B of the second branch, so that the liquid cooling device can directly exchange heat in the fluorine system, the battery heat in the liquid cooling device directly acts on the fluorine system to be received and released, and the heat exchange performance and energy efficiency are improved; that is, the present application removes the water pump, the expansion tank and the water circuit thereof, and directly exchanges heat by using the refrigerant to realize one-time heat exchange, reduce energy consumption and improve energy efficiency;

[0027] (2) In the present application, liquid uniformization design is performed, the liquid cooling assembly is supplied with liquid by the liquid distributor, the refrigerant is uniformly distributed, and the refrigerant flowing to the liquid cooling device can uniformly flow to the plurality of liquid cooling assemblies;

[0028] (3) The liquid inlet of the cold plate is uniformly supplied, the superheat degree is small, local overheating is less, and the battery performance is improved;

[0029] (4) When the direct-cooling heat pump air conditioning system is in heating operation, when the system receives the defrosting instruction, the present application can realize defrosting by setting the heating device, and avoid affecting the running battery;

[0030] (5) The double flow channels, the small branch and the bypass design of the condenser are designed to meet the temperature drop of the high-temperature gaseous refrigerant during normal heating, so that the temperature of the refrigerant entering the cold plate is not more than 35 DEG C, and the battery works in the best working range of 20-30 DEG C; during ultra-low temperature heating (i.e. adverse condition heating), the outer ring temperature is low, and if the condenser branch is used for temperature reduction, condensation is easy, so the plate heat exchanger is combined to realize heat exchange by using the temperature difference between the evaporation and condensation ends, and the exhaust gas temperature reduction is realized;

[0031] (6) In the present application, uniform temperature design is carried out, the cold plate is not overheated, the heat exchange outlet is gas-liquid mixture, and overheat is realized by using the plate heat exchanger and pipeline design. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 A structure schematic diagram of a direct-cooling heat pump air conditioning system for an energy storage temperature control system is provided for the first embodiment of the present application.

[0033] Figure 2 A specific schematic diagram of refrigerant flow in the direct-cooling heat pump air conditioning system of the present application when in refrigeration operation is provided.

[0034] Figure 3 A specific schematic diagram of refrigerant flow in the direct-cooling heat pump air conditioning system of the present application when in conventional heating operation is provided.

[0035] Figure 4 A specific schematic diagram of refrigerant flow in the direct-cooling heat pump air conditioning system of the present application when in adverse heating operation is provided.

[0036] Figure 5 A specific schematic diagram of refrigerant flow in the direct-cooling heat pump air conditioning system of the present application when in defrosting operation is provided.

[0037] Figure 6 A structure schematic diagram of a liquid-cooling air conditioning system of an energy storage temperature control system in the prior art is provided.

[0038] Explanation of Reference Signs:

[0039] 110, compressor; 120, four-way valve; 130, liquid cooling device; 131, liquid cooling throttling element; 132, liquid distributor; 133, liquid cooling assembly; 1331, battery; 1332, cold plate; 134, header; 140, heating device; 150, oil separator; 160, gas-liquid separator; 170, condenser; 180, plate heat exchanger; 191, high-pressure switch; 192, high-pressure sensor; 193, low-pressure switch; 210, first branch; 211, first end; 212, second end; 213, first condensing section; 214, first heat exchange section; 220, second branch; 221, port A; 222, port B; 223, second condensing section; 224, second heat exchange section; 230, bypass pipeline; 231, third filter; 310, first valve; 320, second valve; 330, third valve; 340, fourth valve; 410, first throttling element; 411, first filter; 420, second throttling element; 421, second filter. DETAILED DESCRIPTION

[0040] In order to make the above objectives, characteristics and advantages of the present application more apparent, clear and easy to understand, the technical solutions in the embodiments of the present application are described clearly and completely. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. 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.

[0041] Embodiment One

[0042] Referring to Figure 1 The present application provides a direct-cooling heat pump air conditioning system for an energy storage temperature control system, which combines Figures 2-5 The direct-cooling heat pump air conditioning system comprises a compressor 110, a four-way valve 120, a first branch 210, a second branch 220 and a liquid cooling device 130. The first branch 210 is provided with a first end 211 and a second end 212, and the second branch 220 is provided with a port A 221 and a port B 222. The second end 212 and the port B 222 are respectively connected to two ends of the liquid cooling device 130. The four-way valve 120 is provided with a first valve port, a second valve port, a third valve port and a fourth valve port. The exhaust port of the compressor 110 is in communication with the first valve port, and the suction port of the compressor 110 is in communication with the third valve port. The first end 211 is in communication with the second valve port, and the port A 221 is in communication with the fourth valve port. The first branch 210 is provided with a first condensing section 213 and a first heat exchange section 214 in series. The first heat exchange section 214 is arranged between the first condensing section 213 and the second end 212. The second branch 220 is provided with a second condensing section 223 and a second heat exchange section 224 in series. The second heat exchange section 224 is arranged between the second condensing section 223 and the port B 222.

[0043] Referring to Figure 6 For the liquid cooling air conditioning system of the prior art energy storage temperature control system, the heat emitted by the battery 1331 exchanges heat with the ethylene glycol aqueous solution in the cold plate 1332, and then the heat needs to be exchanged again through the plate heat exchanger 180 of the energy storage air conditioner. At this time, the heat can be received and digested by the fluorine system, so that the heat of the battery 1331 cannot directly act on the fluorine system, and the heat exchange performance and energy efficiency are low.

[0044] In one specific embodiment, the four valve ports of the four-way valve 120 are respectively Figure 1In the diagram, 1, 2, 3, and 4 correspond to the first valve port, 2 to the second valve port, 3 to the third valve port, and 4 to the fourth valve port. The first valve port is connected to the exhaust port of the compressor 110, the third valve port is connected to the intake port of the compressor 110, and the second and fourth valve ports are connected to the first branch 210 and the second branch 220, respectively. Under different operating conditions of the direct cooling heat pump air conditioning system, the operating state of the four-way valve 120 is controlled to control whether the refrigerant flowing from the exhaust port of the compressor 110 flows to the first branch 210 or the second branch 220, thereby controlling the direction of refrigerant flow. One end of the liquid cooling device 130 is connected to the second end 212 of the first branch 210, and the other end is connected to the port B222 of the second branch 220, so that the liquid cooling device 130 can directly exchange heat in the fluorine system, and the heat of the battery 1331 in the liquid cooling device 130 can be directly applied to the fluorine system for reception and release, thereby improving heat exchange performance and energy efficiency; that is, the present invention eliminates water pumps, expansion tanks and their water circuits, and uses refrigerant for direct heat exchange to achieve heat exchange in one step, reducing energy consumption and improving energy efficiency. The direct-cooling heat pump air conditioning system also includes a first condensing section 213 and a second condensing section 223. Specifically, the structure of the first condensing section 213 and the second condensing section 223 is achieved by setting a double flow channel, branch line and valve in the condenser 170. The direct-cooling heat pump air conditioning system also includes a first heat exchange section 214 and a second heat exchange section 224. Specifically, the structure of the first heat exchange section 214 and the second heat exchange section 224 is achieved by the plate heat exchanger 180. The condensation and heat exchange effect of the refrigerant in the system are controlled by controlling the on and off of the first condensing section 213, the second condensing section 223, the first heat exchange section 214 and the second heat exchange section 224.

[0045] Specifically, during cooling operation, by controlling the action of the four-way valve 120 and the on / off state of various valves in the direct-cooling heat pump air conditioning system, the refrigerant discharged from the compressor 110 discharge port is controlled to flow sequentially through the first refrigerant section, the first heat exchange section 214, the liquid cooling device 130, the second heat exchange section 224, and the second refrigerant section, ultimately flowing back to the compressor 110 suction port. During normal heating operation, by controlling the action of the four-way valve 120 and the on / off state of various valves in the direct-cooling heat pump air conditioning system, the refrigerant discharged from the compressor 110 discharge port is controlled to flow sequentially through the second refrigerant section, the first heat exchange section 214, the liquid cooling device 130, the second heat exchange section 224, and the second refrigerant section, ultimately flowing back to the compressor 110 suction port. The refrigerant discharged from the compressor 110's exhaust port flows sequentially through the second heat exchange section 224, the liquid cooling device 130, and the first refrigerant section, and finally returns to the compressor 110's suction port. During this process, it does not pass through the first heat exchange section 214. In harsh heating operation, by controlling the action of the four-way valve 120 and the on / off state of various valves in the direct-cooling heat pump air conditioning system, the refrigerant discharged from the compressor 110's exhaust port is controlled to flow sequentially through the second heat exchange section 224, the liquid cooling device 130, the first heat exchange section 214, and the first refrigerant section, and finally returns to the compressor 110's suction port. During this process, it does not pass through the second refrigerant section.

[0046] Preferably, the length of the first refrigerant section is longer than the length of the second refrigerant section.

[0047] Further, the number of liquid cooling devices 130 is multiple, and the multiple liquid cooling devices 130 are arranged in parallel.

[0048] Specifically, the multiple liquid cooling devices 130 can control the flow of refrigerant flowing into each liquid cooling device 130 according to actual needs, so as to meet the heat exchange effect of the refrigerant flowing through the liquid cooling device 130 under specific conditions. The on-off of each liquid cooling device 130 can realize the first distribution of the refrigerant.

[0049] Further, the liquid cooling device 130 comprises a liquid cooling throttling element 131, a liquid distributor 132, and multiple liquid cooling assemblies 133; the liquid cooling throttling element 131 is connected to the second end 212, the liquid cooling assembly 133 is connected to the port B 222, and the liquid distributor 132 is connected between the liquid cooling throttling element 131 and the liquid cooling assembly 133; the multiple liquid cooling assemblies 133 are arranged in parallel.

[0050] Specifically, since there is uneven distribution of refrigerant in the prior art, the flow through each liquid cooling assembly 133 is different, so the liquid distribution is designed in the present application, the liquid cooling assembly 133 is grouped and supplied with liquid by the liquid distributor 132, the uniform distribution of the refrigerant is realized, the refrigerant flowing to the liquid cooling device 130 can uniformly flow to the multiple liquid cooling assemblies 133, the liquid is uniformly introduced through the cold plate 1332, the superheat is small, the local overheating is less, and the performance of the battery 1331 is improved; the liquid cooling throttling element 131 is arranged, the throttling of the refrigerant is realized by the liquid cooling throttling element 131, the pressure reduction is realized at the same time, the liquid distribution is realized at one time, and the state of the refrigerant is realized to flash to change the evaporation temperature.

[0051] Preferably, the liquid cooling assembly 133 comprises a battery 1331 and a cold plate 1332, the cold plate 1332 is used to adjust the temperature of the battery 1331, the cold plate 1332 is directly in contact with the battery 1331 for heat exchange, and the heat is taken away by the refrigerant to cool the battery 1331. In other words, the liquid cooling device 130 is provided with a cluster of batteries 1331 and a cluster of cold plates 1332.

[0052] Preferably, a multi-stage distribution mode is adopted, which can realize the refrigeration demand of each cluster of liquid cooling devices 130, if the battery 1331 in the liquid cooling assembly 133 works, an instruction is sent to control the on-off of the liquid cooling device 130, and the control is specifically realized by the liquid cooling throttling element 131 in the liquid cooling device 130. The specific control steps are: judging whether the cluster of batteries 1331 works; in the case that the cluster of batteries 1331 does not work, controlling the initial opening degree of the liquid cooling throttling element 131 to be 0 pls; in the case that the cluster of batteries 1331 works, controlling the initial opening degree of the liquid cooling throttling element 131 to be a pls; judging whether the cluster of cold plates 1332 has overheating; if yes, the liquid cooling throttling element 131 maintains the initial opening degree a pls; if no, the liquid cooling throttling element 131 maintains the initial opening degree 0 pls. , if yes, the liquid cooling throttling element 131 maintains the initial opening degree a pls; if no, the liquid cooling throttling element 131 maintains the initial opening degree 0 pls. , the liquid cooling throttling element 131 opening degree is (a+e)pls. Wherein, a is greater than 0. Since the refrigerant state at the outlet of the cold plate 1332 is gas-liquid two-phase, it indicates that the heat exchange of the cold plate 1332 is uniform, and there is basically no phenomenon of insufficient refrigerant cold quantity and the need for superheating, that is, uniform temperature; in order to ensure the uniform temperature of the cold plate 1332, the heat exchange of the cold plate 1332 should be basically latent heat, that is, phase change heat exchange, and the phenomenon of superheating or superheating is small, at this time, throttling control through the liquid cooling throttling element 131 can be realized, and it is guaranteed that the liquid refrigerant at the outlet of the cold plate 1332 is not completely evaporated, and whether the cold plate 1332 is overheated can be determined by the superheat degree, and then adjusted in combination with the liquid cooling throttling element 131 (a, b, c, e, △t are constants).

[0053] Further, the direct-cooling heat pump air conditioning system further comprises: a first valve 310, a first throttling element 410, and a second throttling element 420, the first valve 310 is connected in parallel to both ends of the first heat exchange section 214; the first throttling element 410 is connected in parallel to both ends of the second heat exchange section 224; the second throttling element 420 is connected in series to the first branch 210, and is arranged between the first heat exchange section 214 and the second end 212.

[0054] Specifically, the first valve 310 is connected in parallel to both ends of the first heat exchange section 214, when the refrigerant flowing through the first branch 210 and the refrigerant flowing through the second branch 220 does not need to be heat exchanged (at this time, the refrigerant does not need to pass through the first heat exchange section 214), the first valve 310 is opened, so that the refrigerant of the first branch 210 flows through the first valve 310, thereby avoiding the refrigerant flowing through the first heat exchange section 214; the first throttling element 410 is connected in parallel to both ends of the second heat exchange section 224, and the first throttling element 410 is opened as needed, which can ensure that the refrigerant at the outlet of the second heat exchange section 224 is in a required state; the second throttling element 420 is used for throttling and pressure reduction.

[0055] Preferably, the first throttling element 410 is provided with a first filter 411 at both ends; the second throttling element 420 is provided with a second filter 421 at both ends, and the second filter 421 is connected in series to the first branch 210.

[0056] Further, the direct-cooling heat pump air conditioning system further comprises: a second valve 320, one end of the second valve 320 is connected to the first branch 210 between the second throttling element 420 and the second end 212, and the other end of the second valve 320 is connected to the second branch 220 between the second heat exchange section 224 and the port B 222.

[0057] Specifically, two ends of the second valve 320 are connected to two ends of the liquid cooling device 130, and by controlling the opening and closing of the second valve 320 and the liquid cooling throttling element 131, whether the refrigerant flows through the liquid cooling device 130 can be controlled; when the second valve 320 is opened and the opening degree of the liquid cooling throttling element 131 in each liquid cooling device 130 is 0 pls, the refrigerant flowing out of the first heat exchange section 214 does not flow through the liquid cooling device 130, but directly flows to the second heat exchange section 224 through the second valve 320.

[0058] Preferably, when defrosting, the demand of the battery 1331 cluster is heating, and the system needs to reverse the heating during defrosting. Specifically, the refrigerant is compressed by the compressor 110 to achieve a high-temperature superheated state, and is discharged from the compressor 110 to the four-way valve 120. At this time, the four-way valve 120 is not actuated to ensure that the high-temperature and high-pressure gaseous refrigerant flows to the first condensing section 213 in the first branch 210 to realize the conversion of high-temperature gas to high-temperature liquid. The high-temperature liquid refrigerant flowing to the first heat exchange section 214 exchanges heat with the low-temperature gaseous refrigerant of the second heat exchange section 224 to perform secondary subcooling. Subsequently, it flows out and flows to the second throttling element 420. At present, the second throttling element 420 is throttled and pressure-reduced, the second valve 320 is opened, and the liquid cooling throttling element 131 in each liquid cooling device 130 is closed. After the refrigerant flows through the second valve 320, it flows to the second heat exchange section 224. At this time, the state of the refrigerant is low-temperature and low-pressure liquid refrigerant, which flows to the four-way valve 120 and the electric heating. After the electric heating is turned on, the refrigerant undergoes phase change from liquid to gas, and then returns to the compressor 110.

[0059] Further, the direct-cooling heat pump air conditioning system further comprises: a third valve 330 and a fourth valve 340, the third valve 330 is arranged on the second branch 220, and the third valve 330 is arranged between the second condensing section 223 and the second heat exchange section 224; the fourth valve 340 is connected in parallel to the second branch 220, one end of the fourth valve 340 is connected between the port A 221 and the second condensing section 223, and the other end of the fourth valve 340 is connected between the third valve 330 and the second heat exchange section 224.

[0060] Specifically, by arranging the third valve 330 and the fourth valve 340, the flow direction of the refrigerant discharged from the exhaust port of the compressor 110 after flowing to the second branch 220 through the four-way valve 120 can be controlled; when the third valve 330 is opened and the fourth valve 340 is closed, the refrigerant flowing through the second branch 220 will flow through the third valve 330 and the second condensing section 223; when the third valve 330 is closed and the fourth valve 340 is opened, the refrigerant flowing through the second branch 220 will not flow through the third valve 330 and the second condensing section 223, but will flow through the fourth valve 340 to be directly connected with the four-way valve 120.

[0061] Further, the direct-cooling heat pump air conditioning system further comprises a heating device 140, which is connected between the suction port and the third valve port.

[0062] Specifically, when the direct-cooling heat pump air conditioning system is in heating operation, defrosting is designed: when the system receives a defrosting instruction, the present application does not need to release heat through the cold plate 1332, but can realize defrosting through the heating device 140, thereby avoiding affecting the running battery 1331.

[0063] Further, the direct-cooling heat pump air conditioning system further comprises an oil separator 150 and a gas-liquid separator 160, the oil separator 150 is connected between the exhaust port and the first valve port, and the gas-liquid separator 160 is connected between the suction port and the heating device 140.

[0064] Specifically, the oil separator 150 is used to separate the gas and oil of the direct-cooling heat pump air conditioning system, and specifically, the oil separator 150 separates the compressor 110 oil in the high-temperature and high-pressure steam discharged by the compressor 110, thereby ensuring the reliability of the compressor 110 and ensuring the safe and efficient operation of the direct-cooling heat pump air conditioning system; since the compressor 110 can only compress gas, if the compressor 110 "returns liquid", the compressor 110 is prone to damage, therefore, the gas-liquid separator 160 for separating gas and liquid is added in the direct-cooling heat pump air conditioning system, if the refrigerant is not completely evaporated, the gas-liquid mixed refrigerant can first flow back to the gas-liquid separator 160 and separate the gas therefrom, so that the separated gas flows back to the compressor 110, and the separated liquid remains in the gas-liquid separator 160, thereby buffering the gas-liquid separator 160.

[0065] Further, the direct-cooling heat pump air conditioning system further comprises a bypass pipeline 230 and a third filter 231, one end of the bypass pipeline 230 is connected to the oil separator 150, the other end of the bypass pipeline 230 is connected to the suction port, and the third filter 231 is connected in series to the bypass pipeline 230.

[0066] Specifically, a small amount of compressor 110 oil is brought out by the high-temperature and high-pressure steam refrigerant compressed by the compressor 110, and after flowing through the oil separator 150, the gas and oil are separated due to the special structure thereof, the oil flows to the bottom of the oil separator 150 under the influence of gravity, and the oil flows through the third filter 231 and the capillary tube of the bypass pipeline 230 under the suction force of the compressor 110, and then returns to the compressor 110.

[0067] Further, the direct-cooling heat pump air conditioning system further comprises a condenser 170 and a plate heat exchanger 180, the condenser 170 is provided with a first condensing section 213 and a second condensing section 223, and the plate heat exchanger 180 is provided with a first heat exchange section 214 and a second heat exchange section 224.

[0068] Specifically, the structure of the first condensing section 213 and the second condensing section 223 is realized by the condenser 170, so that the overall structure of the direct-cooling heat pump air conditioning system is more simple; since the optimal working environment temperature of the battery cell is about 25-30℃, and the cold plate 1332 has limited pressure bearing, the high-pressure and high-temperature gaseous refrigerant discharged by the compressor 110 needs to be further cooled, and therefore a pre-cooling design is performed, specifically: a double-flow channel, a small branch and a bypass design of the condenser 170 are designed to meet the temperature drop of the high-temperature gaseous refrigerant in the normal heating mode, so that the temperature of the refrigerant entering the cold plate 1332 does not exceed 35℃, and the battery 1331 works in the optimal working range of 20-30℃; in the ultra-low temperature heating (i.e. adverse condition heating) mode, if the condenser 170 branch is used for cooling, it is easy to condense, and therefore the plate heat exchanger 180 is combined to realize heat exchange by using the temperature difference between the evaporation and condensation ends, so that the exhaust gas is cooled.

[0069] The structure of the first heat exchange section 214 and the second heat exchange section 224 is realized by the plate heat exchanger 180, so that the refrigerant flowing through the first heat exchange section 214 and the second heat exchange section 224 is heat-exchanged by the plate heat exchanger 180. Since the high-pressure liquid refrigerant at the outlet of the condenser 170 and the low-temperature gas-liquid two-phase refrigerant at the outlet of the cold plate 1332 are heat-exchanged, the high-pressure liquid refrigerant at the outlet of the condenser 170 cannot be phase-changed, so the temperature is reduced to realize secondary supercooling and improve energy efficiency; the gas-liquid two-phase refrigerant at the outlet of the cold plate 1332 is completely phase-changed into a gaseous state, and even superheated, so that the state of the refrigerant entering the compressor 110 is not liquid to prevent liquid hammer. That is, in the present application, uniform temperature design is performed, the cold plate 1332 is not superheated, the heat exchange outlet is a gas-liquid mixture, and superheating is realized by the plate heat exchanger 180 and the pipeline design.

[0070] Preferably, in order to ensure that the cold plate 1332 is uniformly heat-exchanged, the cold plate 1332 should basically be heat-exchanged by latent heat, i.e. phase-change heat exchange, and superheating is very small, which can be realized by throttling control through the throttling element, so that the liquid refrigerant entering the cold plate 1332 can be completely evaporated, and whether the cold plate 1332 is superheated can be determined by the superheat degree; and since the outlet of the cold plate 1332 is not superheated, in order to avoid liquid compression, a superheating section needs to be added after the cold plate 1332 (i.e. the plate heat exchanger 180 is used to transfer the high temperature at the outlet of the condenser to the low-temperature liquid refrigerant at the outlet of the cold plate 1332 to realize evaporation superheating).

[0071] In a specific embodiment, when the direct-cooling heat pump air conditioning system is in a cooling operation, the refrigerant flow direction is as follows: Figure 2As shown, the unit receives the start-up instruction, the refrigerant is compressed by the compressor 110 to achieve a high-temperature superheated state, and is discharged from the compressor 110 to the oil separator 150 and the four-way valve 120. At this time, the four-way valve 120 does not act, and the high-temperature and high-pressure gaseous refrigerant is ensured to flow to the first condensing section 213 in the condenser 170. The phase change heat transfer of the refrigerant in the condenser 170 is enhanced by the fan, and the high-temperature gaseous state is converted to a high-temperature liquid state. In order to ensure performance, the condenser 170 is optimized, and a supercooling section (that is, the first condensing section 213) is added, so that the refrigerant at the outlet of the condenser 170 is supercooled. The refrigerant then flows from the condenser 170 to the plate heat exchanger 180, and the first valve 310 is not opened. The high-temperature liquid refrigerant flowing to the plate heat exchanger 180 exchanges heat with the low-temperature gaseous and liquid refrigerant at the outlet of the other side (that is, the second heat exchange section 224 side) of the plate heat exchanger 180, and is subjected to secondary supercooling. Then, the refrigerant flows out of the plate heat exchanger 180, flows to the second filter 421 and the second throttling element 420. At present, the second throttling element 420 does not act, the valve step is fully opened, the second valve 320 is closed, and the refrigerant flows to the battery 1331 cluster and then flows to the cold plate 1332 in stages. Each sub-battery 1331 cluster has a liquid cooling throttling element 131. The refrigerant is throttled by the liquid cooling throttling element 131 first, and the state of the refrigerant changes from high-pressure and high-temperature liquid state to low-temperature and low-pressure liquid state (flash evaporation will cause the evaporation temperature to decrease). Then, the refrigerant is divided into third sub-branches by the distributor 132, and a plurality of refrigerant flows to the battery 1331 cold plate 1332 for heat exchange. The low-temperature and low-pressure liquid refrigerant absorbs heat from the battery 1331, and the phase changes, so that the refrigerant at the outlet of the cold plate 1332 after heat exchange is in a gaseous and liquid mixed state. At this time, the refrigerant passes through the current collector, is gathered together, flows to the plate heat exchanger 180, and the first throttling element 410 is closed. The low-temperature and low-pressure gaseous and liquid mixed refrigerant at the outlet of the cold plate 1332 exchanges heat with the high-temperature liquid refrigerant at the outlet of the condenser 170 on the other side of the plate heat exchanger 180. Due to the absorption of heat, the state of the refrigerant is a low-pressure gaseous refrigerant at room temperature. Then, the refrigerant flows through the four-way valve 120, the electric heating device 140, the gas-liquid separator 160, and finally returns to the compressor 110. The fourth valve 340 and the electric heating device 140 are closed.

[0072] When the direct-cooling heat pump air conditioning system is in normal heating operation, the refrigerant flows as shown in FIG. 4. Figure 3As shown, the unit receives the start-up instruction, the refrigerant is compressed by the compressor 110 to achieve a high-temperature overheating state, and is discharged from the compressor 110 to the oil separator 150 and the four-way valve 120. At this time, the four-way valve 120 is reversed to ensure that the high-temperature and high-pressure gaseous refrigerant flows to the second condensing section 223 in the condenser 170, realizing the conversion of high-temperature gas to medium-temperature gas. The fourth valve 340 is closed, and the third valve 330 is opened. The refrigerant then flows from the condenser 170 to the plate heat exchanger 180, and the first valve 310 is opened. The medium-temperature gaseous refrigerant flowing to the plate heat exchanger 180 does not exchange heat with the low-temperature liquid refrigerant at the outlet of the other side (i.e., the side of the first heat exchange section 214) of the plate heat exchanger 180. The first throttling element 410 is opened, and most of the gaseous refrigerant flows through. The second valve 320 is closed, and the refrigerant flows to the battery 1331 cluster and is then divided by the manifold 134 to flow to the cold plate 1332. The refrigerant undergoes phase change in the cold plate 1332, realizing that the state of the refrigerant at the outlet of the cold plate 1332 is gas-liquid. Then, the refrigerant flows through the distributor 132, and all the groups of liquid cooling throttling elements 131 are fully opened. After being collected together, the refrigerant flows to the second throttling element 420 for throttling and pressure reduction. Flashing occurs during throttling and pressure reduction, and the temperature of the refrigerant decreases. At this time, the state of the refrigerant is low-temperature and low-pressure liquid refrigerant. The refrigerant flows through the first valve 310 without flowing through the first heat exchange section 214, and directly flows to the condenser 170 for heat exchange. The state of the refrigerant after heat exchange is low-temperature and low-pressure gaseous refrigerant, which then flows to the four-way valve 120, the electric heating device 140, the gas-liquid separator 160, and finally returns to the compressor 110.

[0073] When the direct-cooling heat pump air conditioning system is in a bad situation for heating operation, the refrigerant flows as shown in FIG. 6. Figure 4As shown, the unit receives a start-up instruction, the refrigerant is compressed by the compressor 110 to achieve a high-temperature superheated state, and is discharged from the compressor 110 to the oil separator 150 and the four-way valve 120. At this time, the four-way valve 120 is reversed to ensure that the high-temperature and high-pressure gaseous refrigerant flows to the plate heat exchanger 180, does not flow through the second condensing section 223 in the condenser 170, and realizes the conversion of high-temperature gas to medium-temperature gas. The fourth valve 340 is opened, and the third valve 330 is closed. The high-temperature gaseous refrigerant flowing to the plate heat exchanger 180 exchanges heat with the low-temperature liquid refrigerant at the outlet of the other side of the plate heat exchanger 180 (i.e., the first heat exchange section 214 side). The first throttling element 410 is opened as needed to ensure that the refrigerant at the outlet of the plate heat exchanger 180 is gaseous. The refrigerant flows to the battery 1331 cluster and is then divided by the manifold 134 to flow to the cold plate 1332. The refrigerant undergoes a phase change in the cold plate 1332 to achieve a state of gas-liquid at the outlet of the cold plate 1332. Subsequently, the refrigerant flows through the distributor 132, the liquid cooling throttling elements 131 of each group are fully opened, is collected together, flows to the second throttling element 420, and is throttled and depressurized. The throttling and depressurizing occur with flashing, and the temperature of the refrigerant decreases. At this time, the refrigerant is low-temperature and low-pressure liquid refrigerant. The second valve 320 is closed, the refrigerant flows through the plate heat exchanger 180, exchanges heat with the high-temperature gaseous refrigerant on the other side of the plate heat exchanger 180, and then flows to the condenser 170 for heat exchange. The refrigerant after heat exchange is low-temperature and low-pressure gaseous refrigerant, which then flows to the four-way valve 120, the electric heating device 140, the gas-liquid separator 160, and finally returns to the compressor 110.

[0074] When the direct-cooling heat pump air conditioning system is in defrosting operation, the refrigerant flows as shown Figure 5 As shown, the unit receives a defrosting instruction, the refrigerant is compressed by the compressor 110 to achieve a high-temperature superheated state, and is discharged from the compressor to the oil separator 150 and the four-way valve 120. At this time, the four-way valve 120 does not act, ensuring that the high-temperature and high-pressure gaseous refrigerant flows to the condenser 170. The fan cooperates to enhance the phase change heat exchange of the refrigerant in the condenser 170, realizing the conversion of high-temperature gas to liquid. The refrigerant then flows from the condenser 170 to the plate heat exchanger 180, and the first valve 310 is not opened. The high-temperature liquid refrigerant after flowing to the plate heat exchanger exchanges heat with the low-temperature gaseous refrigerant at the outlet of the other side (i.e., the second heat exchange section 224) of the plate heat exchanger, and is subjected to secondary supercooling. Subsequently, the refrigerant flows out of the plate heat exchanger 180, flows to the second filter 421 and the second throttling element 420, the second throttling element 420 is throttled and depressurized, the second valve 320 is opened, and the liquid cooling throttling elements 131 of the battery 1331 cluster are closed. After the refrigerant flows through the second valve 320, it flows to the plate heat exchanger. At this time, the refrigerant is low-temperature and low-pressure liquid refrigerant, flows to the first throttling element, the valve is fully opened, flows to the four-way valve 120, the electric heating device 140, and the electric heating device 140 is turned on. The refrigerant undergoes a phase change from liquid to gas, and then flows through the gas-liquid separator 160 to return to the compressor 110.

[0075] It should be pointed out finally that the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit the same; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can still be modified, or some technical features therein can be replaced equivalently; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A direct-cooling heat pump air conditioning system for an energy storage temperature control system, characterized by, The direct-cooling heat pump air conditioning system comprises: a compressor (110), a four-way valve (120), a first branch (210), a second branch (220) and a liquid cooling device (130), the first branch (210) is provided with a first end (211) and a second end (212), the second branch (220) is provided with a port A (221) and a port B (222), and the second end (212) and the port B (222) are respectively connected to two ends of the liquid cooling device (130); the four-way valve (120) is provided with a first valve port, a second valve port, a third valve port and a fourth valve port, and an exhaust port of the compressor (110) and the first valve port are in communication, an air inlet of the compressor (110) and the third valve port are in communication, the first end (211) and the second valve port are in communication, and the port A (221) and the fourth valve port are in communication; the first branch (210) is provided with a first condensing section (213) and a first heat exchange section (214) in series, and the first heat exchange section (214) is arranged between the first condensing section (213) and the second end (212); the second branch (220) is provided with a second condensing section (223) and a second heat exchange section (224) in series, and the second heat exchange section (224) is arranged between the second condensing section (223) and the port B (222); the liquid cooling device (130) comprises: a liquid cooling throttling element (131), a liquid distributor (132) and a plurality of liquid cooling assemblies (133); the liquid cooling throttling element (131) is connected to the second end (212), the liquid cooling assemblies (133) are connected to the port B (222), and the liquid distributor (132) is connected between the liquid cooling throttling element (131) and the liquid cooling assemblies (133); the plurality of liquid cooling assemblies (133) are arranged in parallel; the direct-cooling heat pump air conditioning system further comprises: a condenser (170), and the condenser (170) is provided with the first condensing section (213) and the second condensing section (223); a plate heat exchanger (180), and the plate heat exchanger (180) is provided with the first heat exchange section (214) and the second heat exchange section (224).

2. The direct-cooling heat pump air conditioning system according to claim 1, wherein the number of the liquid cooling devices (130) is multiple, and the plurality of liquid cooling devices (130) are arranged in parallel.

3. The direct-cooling heat pump air conditioning system of claim 1, wherein, the direct-cooling heat pump air conditioning system further comprises: a first valve (310) connected in parallel to two ends of the first heat exchange section (214); a first throttling element (410) connected in parallel to two ends of the second heat exchange section (224); a second throttling element (420) connected in series to the first branch (210), and the second throttling element (420) is arranged between the first heat exchange section (214) and the second end (212).

4. The direct-cooling heat pump air conditioning system of claim 3, wherein, the direct-cooling heat pump air conditioning system further comprises: A second valve (320) is connected to the first branch (210) between the second throttling element (420) and the second end (212), and connected to the second branch (220) between the second heat exchange section (224) and the port B (222).

5. The direct-cooling heat pump air conditioning system of claim 1, wherein, The direct-cooling heat pump air conditioning system further comprises: A third valve (330) is arranged on the second branch (220) and arranged between the second condensing section (223) and the second heat exchange section (224); A fourth valve (340) is connected in parallel to the second branch (220), and one end of the fourth valve (340) is connected between the port A (221) and the second condensing section (223), and the other end of the fourth valve (340) is connected between the third valve (330) and the second heat exchange section (224).

6. The direct-cooling heat pump air conditioning system of claim 1, wherein, The direct-cooling heat pump air conditioning system further comprises: A heating device (140) is connected between the suction port and the third valve port.

7. The direct-cooling heat pump air conditioning system of claim 6, wherein, The direct-cooling heat pump air conditioning system further comprises: An oil separator (150) is connected between the exhaust port and the first valve port; A gas-liquid separator (160) is connected between the suction port and the heating device (140).

8. The direct-cooling heat pump air conditioning system of claim 7, wherein, The direct-cooling heat pump air conditioning system further comprises: A bypass pipeline (230) is connected at one end to the oil separator (150) and at the other end to the suction port; A third filter (231) is connected in series to the bypass pipeline (230).

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