Direct cooling heat pump air conditioning system for energy storage temperature control system

Abstract

The invention 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 a port A and a port B, and the second end and the port B are respectively connected with 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, an exhaust port of the compressor is communicated with the first valve port, an air suction port of the compressor is communicated with the third valve port, a first end is communicated with the second valve port, and a port A is communicated with the fourth valve port; a first condensation section and a first heat exchange section are connected to the first branch in series, and the first heat exchange section is arranged between the first condensation section and the second end. A second condensation section and a second heat exchange section are connected to the second branch in series, and the second heat exchange section is arranged between the second condensation section and the port B. The technical problem that in the prior art, a liquid cooling system needs multiple heat exchange, cold energy cannot directly act on a heating battery cell, and the heat exchange performance is low is solved.

Description

Technical Field

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

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

[0003] The temperature control units currently on the market are mainly liquid-cooled and air-cooled energy storage air conditioners. Among them, liquid-cooled air conditioners with a refrigerant of 50% ethylene glycol aqueous solution have higher heat exchange performance and energy efficiency than air-cooled air conditioners; but from the principle of heat exchange, after the heat released by the battery exchanges heat with the ethylene glycol aqueous solution in the cold plate, its heat needs to be exchanged again through the plate heat exchanger of the energy storage air conditioner, and the heat at this time can be received and digested by the fluorine system. It can be seen that the liquid cooling system in the prior art requires multiple heat exchanges and cannot directly apply the cold to the heating battery core, resulting in low heat exchange performance. Summary of the invention

[0004] The present invention solves the technical problem in the prior art that the liquid cooling system requires multiple heat exchanges and cannot directly apply the cooling energy to the heated battery core, resulting in low heat exchange performance.

[0005] To solve the above problems, the present invention 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 the 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 is connected to the first valve port, the intake port of the compressor is connected to the third valve port, the first end and the second valve port are connected, and the port A is connected to the fourth valve port; the first branch is connected in series with a first condensing section and a first heat exchange section, and the first heat exchange section is arranged between the first condensing section and the second end; the second branch is connected in series 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.

[0006] Compared with the prior art, the technical effect achieved by adopting this technical solution is as follows: the first valve port is connected to the exhaust port of the compressor, the third valve port is connected to the air intake port of the compressor, the second valve port and the fourth valve port are connected to the first branch and the second branch respectively, and in different operating states of the direct cooling heat pump air conditioning system, by controlling the operating state of the four-way valve, the refrigerant flowing out of the exhaust port of the compressor is controlled to flow to the first branch or the second branch 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, so that the battery heat in the liquid cooling device directly acts on the fluorine system to receive and release, thereby improving the heat exchange performance and energy efficiency; that is, the present invention removes the water pump, expansion tank, etc. and their waterways, uses the refrigerant for direct heat exchange, realizes one-time heat exchange, reduces energy consumption, and improves energy efficiency. The direct cooling heat pump air conditioning system also includes 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 setting a double flow channel, a branch and a valve in the condenser; the direct cooling heat pump air conditioning system also includes 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 a plate heat exchanger; the condensation and heat exchange effects of the refrigerant in the system are controlled by controlling the on and off of the first condensing section, the second condensing section, the first heat exchange section and the second heat exchange section.

[0007] In an embodiment of the present invention, there are multiple liquid cooling devices, and the multiple liquid cooling devices are arranged in parallel.

[0008] Compared with the prior art, the technical effect achieved by adopting this technical solution is that the flow rate of the refrigerant into each liquid cooling device can be controlled according to actual needs by setting up multiple liquid cooling devices, 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 achieved by turning each liquid cooling device on and off.

[0009] In one example of the present invention, the liquid cooling device includes: a liquid cooling throttling element, a liquid distributor and a plurality of liquid cooling components; the liquid cooling throttling element is connected to the second end, the liquid cooling component is connected to port B, and the liquid distributor is connected between the liquid cooling throttling element and the liquid cooling component; and the plurality of liquid cooling components are arranged in parallel.

[0010] Compared with the prior art, the technical effect achieved by adopting this technical scheme is as follows: Since the prior art has the problem of uneven refrigerant distribution and different flow rates flowing through each liquid-cooled component, a liquid-evening design is performed in the present invention, and the grouped liquid supply of the liquid-cooled components is realized through a liquid separator, so as to realize uniform distribution of the refrigerant, so that the refrigerant flowing to the liquid cooling device can flow evenly to multiple liquid-cooled components; a liquid-cooling throttling element is provided, and throttling of the refrigerant is realized through the liquid-cooling throttling element, so as to realize one-time liquid separation while realizing pressure reduction, and at the same time, the refrigerant state is flashed to change the evaporation temperature.

[0011] In one example of the present invention, the direct cooling heat pump air conditioning system also includes: a first valve, the first valve is connected in parallel to the two ends of the first heat exchange section; a first throttling element, the first throttling element is connected in parallel to the two ends of the second heat exchange section; a second throttling element, the second throttling element is connected in series to the first branch, and the second throttling element is arranged between the first heat exchange section and the second end.

[0012] Compared with the prior art, the technical effect achieved by adopting this technical solution is as follows: a first valve is connected in parallel at both ends of the first heat exchange section. When the refrigerant flowing through the first branch and the refrigerant flowing through the second branch do 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 to allow the refrigerant in the first branch to flow through the first valve, thereby preventing the refrigerant from flowing through the first heat exchange section; a first throttling element is connected in parallel at both ends of the second heat exchange section. The first throttling element is opened as needed to ensure that the refrigerant state at the outlet of the second heat exchange section is the required state; the second throttling element is used for throttling and reducing pressure.

[0013] In one example of the present invention, the direct cooling heat pump air conditioning system also includes: a second valve, one end of the second valve is connected to the first branch between the second throttling element and the second end, and the other end of the second valve is connected to the second branch between the second heat exchange section and port B.

[0014] Compared with the prior art, the technical effect achieved by adopting this technical solution is 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 and off of the second valve and the liquid cooling throttling element, it is possible to control whether the refrigerant flows through the liquid cooling device; when the second valve is opened and the opening of the liquid cooling throttling elements in each liquid cooling device is 0pls, the refrigerant flowing out of the outlet of the first heat exchange section does not flow through the liquid cooling device, but flows directly to the second heat exchange section through the second valve.

[0015] In one example of the present invention, the direct cooling heat pump air conditioning system also includes: a third valve, which is arranged on the second branch and the third valve is arranged between the second condensing section and the second heat exchange section; a fourth valve, which is connected in parallel to the second branch and one end of the fourth valve is connected to between port A and the second condensing section, and the other end of the fourth valve is connected to between the third valve and the second heat exchange section.

[0016] Compared with the prior art, the technical effect achieved by adopting this technical solution is as follows: by setting the third valve and the fourth valve, the flow direction of the refrigerant discharged from the compressor exhaust port after passing through the four-way valve and flowing 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 will flow through the third valve and the second condensation 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 condensation section, but flows through the fourth valve and is directly connected to the four-way valve.

[0017] In one example of the present invention, the direct cooling heat pump air conditioning system further includes: a heating device connected between the air intake port and the third valve port.

[0018] Compared with the prior art, the technical effect achieved by adopting this technical solution is as follows: when the direct cooling heat pump air-conditioning system is in heating operation, when the system receives a defrost instruction, the present invention can achieve defrost by setting a heating device, thereby avoiding affecting the running battery.

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

[0020] Compared with the prior art, the technical effect achieved by adopting this technical scheme is 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 from 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", it is easy to cause damage to the compressor. Therefore, a gas-liquid separator for separating gas and liquid is added to 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, which plays a buffering role for the gas-liquid separator.

[0021] In one example of the present invention, the direct cooling heat pump air conditioning system further includes: a bypass pipeline, one end of which is connected to the oil separator, and the other end of which is connected to the air intake port; and a third filter, which is connected in series to the bypass pipeline.

[0022] Compared with the existing technology, the technical effect achieved by adopting this technical solution is as follows: the high-temperature and high-pressure steam refrigerant compressed by the compressor brings out a small amount of compressor oil, and after flowing through the oil separator, the gas and oil are separated due to its special structure. The oil is affected by gravity and flows to the bottom of the oil separator. Under the suction of the compressor, the oil flows through the third filter and capillary tube of the bypass pipeline, and then returns to the compressor.

[0023] In one example of the present invention, the direct cooling heat pump air conditioning system further includes: a condenser, the condenser having a first condensation section and a second condensation section; and a plate heat exchanger, the plate heat exchanger having a first heat exchange section and a second heat exchange section.

[0024] Compared with the prior art, the technical effect achieved by adopting this technical solution is as follows: the structure of the first condensation section and the second condensation section is realized by the condenser, so that the overall structure of the direct cooling heat pump air conditioning system is more concise, specifically: the double flow channel, small branch and bypass design of the condenser are designed to meet the temperature drop of the high-temperature gaseous refrigerant during conventional heating, so that the temperature of the refrigerant entering the cold plate does not exceed 35°C, and the battery works in the optimal working range of 20-30°C; when heating at ultra-low temperature (that is, heating under bad conditions), considering the low temperature of the outer ring, if the condenser branch is used for cooling, it is easy to condense, so the plate heat exchanger is combined to use the temperature difference between the two ends of evaporation and condensation for heat exchange, and exhaust gas cooling is realized; the structure of the first heat exchange section and the second heat exchange section is realized by the plate heat exchanger, so that the refrigerant flowing through the first heat exchange section and the second heat exchange section can realize heat exchange through the plate heat exchanger. In the present invention, a uniform temperature design is performed, the cold plate is not overheated, the heat exchange outlet is a gas-liquid mixture, and the plate heat exchanger and its pipeline design are used to realize overheating.

[0025] After adopting the technical solution of the present invention, the following technical effects can be achieved: (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, so that the heat of the battery in the liquid cooling device directly acts on the fluorine system to receive and release, thereby improving the heat exchange performance and energy efficiency; that is, the present invention removes the water pump, expansion tank, etc. and their water channels, uses the refrigerant to directly exchange heat, realizes one-time heat exchange, reduces energy consumption, and improves energy efficiency; (2) In the present invention, a uniform liquid design is performed to realize grouped liquid supply of liquid cooling components through a liquid distributor, thereby realizing uniform distribution of the refrigerant, so that the refrigerant flowing to the liquid cooling device can flow evenly to multiple liquid cooling components; (3) Liquid is evenly fed into the cold plate, with low overheating and less local overheating, thus improving battery performance; (4) When the direct cooling heat pump air conditioning system is in heating operation, when the system receives a defrost instruction, the present invention can achieve defrost by providing a heating device to avoid affecting the running battery; (5) Design the double flow channel, small branch and bypass design of the condenser to meet the temperature drop of the high-temperature gaseous refrigerant during conventional heating, so that the refrigerant temperature entering the cold plate does not exceed 35°C, allowing the battery to work in the optimal working range of 20-30°C; during ultra-low temperature heating (that is, heating under severe conditions), considering the low temperature of the outer ring, if the condenser branch is used for cooling, it is easy to condense. Therefore, a plate heat exchanger is combined to use the temperature difference between the evaporation and condensation ends for heat exchange, thereby achieving exhaust gas cooling; (6) In the present invention, a uniform temperature design is performed, the cold plate is not overheated, the heat exchange outlet is a gas-liquid mixture, and superheating is achieved by using a plate heat exchanger and its pipeline design. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1A schematic diagram of the structure of a direct cooling heat pump air conditioning system for an energy storage temperature control system provided in the first embodiment of the present invention; Figure 2 A specific schematic diagram of the refrigerant flow direction in the direct cooling heat pump air conditioning system of the present invention during refrigeration operation; Figure 3 It is a specific schematic diagram of the refrigerant flow direction in the direct cooling heat pump air conditioning system of the present invention during conventional heating operation; Figure 4 It is a specific schematic diagram of the refrigerant flow direction in the direct cooling heat pump air conditioning system of the present invention when operating in severe heating conditions; Figure 5 It is a specific schematic diagram of the refrigerant flow direction in the direct cooling heat pump air conditioning system of the present invention during defrosting operation; Figure 6 It is a structural schematic diagram of a liquid cooling air conditioning system of an energy storage temperature control system in the prior art.

[0027] Description of reference numerals: 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; 2 12, 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 line; 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

[0028] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and understandable, the technical solutions in the embodiments of the present invention are described clearly and completely. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] [Example 1] See also Figure 1 The present invention provides a direct cooling heat pump air conditioning system for an energy storage temperature control system, combined with Figure 2-Figure 5The direct cooling heat pump air conditioning system includes: 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 A221 and a port B222, and the second end 212 and the port B222 are respectively connected to the 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 the exhaust port of the compressor 110 and the first valve port are connected to the exhaust port of the compressor 110. A valve port is connected, the suction port of the compressor 110 is connected to the third valve port, the first end 211 is connected to the second valve port, and the port A221 is connected to the fourth valve port; the first branch 210 is connected in series with the first condensing section 213 and the first heat exchange section 214, 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 connected in series with the second condensing section 223 and the second heat exchange section 224, and the second heat exchange section 224 is arranged between the second condensing section 223 and the port B222.

[0030] See also Figure 6 It is a liquid-cooled air-conditioning system of the energy storage temperature control system of the prior art. After the heat released by the battery 1331 is exchanged with the ethylene glycol aqueous solution in the cold plate 1332, the heat needs to be exchanged again through the plate heat exchanger 180 of the energy storage air-conditioning system. Only then can the heat be received and digested by the fluorine system, resulting in that the heat of the battery 1331 cannot directly act on the fluorine system, and the heat exchange performance and energy efficiency are low.

[0031] In a specific embodiment, the four valve ports of the four-way valve 120 are respectively as follows: Figure 1In the figure, 1 corresponds to the first valve port, 2 corresponds to the second valve port, 3 corresponds to the third valve port, and 4 corresponds 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, the second valve port and the fourth valve port 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, by controlling the operating state of the four-way valve 120, it is controlled whether the refrigerant flowing out of the exhaust port of the compressor 110 flows to the first branch 210 or the second branch 220, so as to control the flow direction of the refrigerant. 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, so that the heat of the battery 1331 in the liquid cooling device 130 directly acts on the fluorine system to receive and release, thereby improving the heat exchange performance and energy efficiency; that is, the present invention eliminates the water pump, expansion tank, etc. and their water channels, and uses refrigerant for direct heat exchange, thereby achieving one-time heat exchange, 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 realized by setting a double flow channel, a branch and a 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 realized by the plate heat exchanger 180; the condensation and heat exchange effects 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.

[0032] Specifically, during refrigeration operation, by controlling the action of the four-way valve 120 and the on-off of each valve in the direct cooling heat pump air-conditioning system, the refrigerant discharged from the exhaust port of the compressor 110 is controlled to flow 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 in sequence, and finally flows back to the air intake port of the compressor 110; during conventional heating operation, by controlling the action of the four-way valve 120 and the on-off of each valve in the direct cooling heat pump air-conditioning system, the refrigerant discharged from the exhaust port of the compressor 110 is controlled to flow through the second The condensing section 223, the second heat exchange section 224, the liquid cooling device 130 and the first refrigerant section finally flow back to the air intake of the compressor 110, and in this process, it does not pass through the first heat exchange section 214; during the severe heating operation, by controlling the action of the four-way valve 120 and the on-off of each valve in the direct cooling heat pump air-conditioning system, the refrigerant discharged from the exhaust port of the compressor 110 is controlled to flow through the second heat exchange section 224, the liquid cooling device 130, the first heat exchange section 214 and the first refrigerant section in sequence, and finally flow back to the air intake of the compressor 110, and in this process, it does not pass through the second refrigerant section.

[0033] Preferably, the length of the first refrigerant section is longer than the length of the second refrigerant section.

[0034] Furthermore, there are multiple liquid cooling devices 130 , and the multiple liquid cooling devices 130 are arranged in parallel.

[0035] Specifically, multiple liquid cooling devices 130 can be provided to control the flow of the refrigerant 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 first-level distribution of the refrigerant can be achieved by turning each liquid cooling device 130 on and off.

[0036] Furthermore, the liquid cooling device 130 includes: a liquid cooling throttling element 131, a liquid separator 132 and a plurality of liquid cooling components 133; the liquid cooling throttling element 131 is connected to the second end 212, the liquid cooling component 133 is connected to the port B222, and the liquid separator 132 is connected between the liquid cooling throttling element 131 and the liquid cooling component 133; the plurality of liquid cooling components 133 are arranged in parallel.

[0037] Specifically, since the prior art has the problem of uneven refrigerant distribution and different flow rates through each liquid cooling component 133, a uniform liquid design is performed in the present invention, and the grouped liquid supply of the liquid cooling component 133 is realized through the liquid separator 132, so as to realize the uniform distribution of the refrigerant, so that the refrigerant flowing to the liquid cooling device 130 can flow evenly to multiple liquid cooling components 133, and the liquid enters evenly through the cold plate 1332, with low overheating and less local overheating, thereby improving the performance of the battery 1331; a liquid cooling throttling element 131 is provided, and throttling of the refrigerant is realized through the liquid cooling throttling element 131, so as to realize one-time liquid separation while realizing pressure reduction, and at the same time, the refrigerant state is flashed to change the evaporation temperature.

[0038] Preferably, the liquid cooling assembly 133 includes 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 in direct 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, a battery 1331 cluster and a cold plate 1332 cluster are provided in the liquid cooling device 130.

[0039] Preferably, a multi-level distribution method is adopted to realize the independent cooling demand of each cluster of liquid cooling devices 130. If the battery 1331 in the liquid cooling component 133 is working, an instruction is issued to control the on and off of the liquid cooling device 130, which is specifically controlled by the liquid cooling throttling element 131 in the liquid cooling device 130. The specific control steps are: judging whether the battery 1331 cluster is working; when the battery 1331 cluster is not working, controlling the initial opening of the liquid cooling throttling element 131 to 0 pls; when the battery 1331 cluster is working, controlling the initial opening of the liquid cooling throttling element 131 to a pls; judging whether the overheat degree of the cold plate 1332 cluster is If yes, the liquid-cooled throttling element 131 maintains the initial opening a pls; if no, , the opening of the liquid cooling throttling element 131 is (a+e)pls. Among them, a is greater than 0. Since the refrigerant state at the outlet of the cold plate 1332 is gas-liquid two-phase, it means that the heat exchange of the cold plate 1332 is uniform, and there is basically no phenomenon of insufficient refrigerant cooling and overheating, that is, uniform temperature; in order to ensure the uniform heat exchange of the cold plate 1332, the heat exchange of the cold plate 1332 should be basically latent heat, that is, phase change heat exchange, without overheating or very small overheating phenomenon, at this time, the throttling control of the liquid cooling throttling element 131 can be achieved to ensure that the liquid refrigerant out of the cold plate 1332 is not completely evaporated. The superheat can be used to determine whether the cold plate 1332 is overheated, and then adjusted in combination with the liquid cooling throttling element 131 (a, b, c, e, △t are constants).

[0040] Furthermore, the direct cooling heat pump air conditioning system also includes: a first valve 310, a first throttling element 410 and a second throttling element 420, the first valve 310 is connected in parallel to the two ends of the first heat exchange section 214; the first throttling element 410 is connected in parallel to the two ends of the second heat exchange section 224; the second throttling element 420 is 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.

[0041] Specifically, the first valve 310 is connected in parallel at 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 do not need to exchange heat (at this time the refrigerant does not need to pass through the first heat exchange section 214), the first valve 310 is opened to allow the refrigerant in the first branch 210 to flow through the first valve 310, thereby preventing the refrigerant from flowing through the first heat exchange section 214; the first throttling element 410 is connected in parallel at both ends of the second heat exchange section 224. The first throttling element 410 is opened as needed to ensure that the refrigerant state at the outlet of the second heat exchange section 224 is the required state; the second throttling element 420 is used for throttling and reducing pressure.

[0042] Preferably, first filters 411 are provided at both ends of the first throttling element 410 ; second filters 421 are provided at both ends of the second throttling element 420 , and the second filter 421 is connected in series to the first branch 210 .

[0043] Furthermore, the direct cooling heat pump air conditioning system also includes: 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 B222.

[0044] Specifically, the two ends of the second valve 320 are connected to the two ends of the liquid cooling device 130. By controlling the on and off of the second valve 320 and the liquid cooling throttling element 131, it is possible to control whether the refrigerant flows through the liquid cooling device 130; when the second valve 320 is opened and the opening of the liquid cooling throttling elements 131 in each liquid cooling device 130 is 0pls, the refrigerant flowing out from the outlet of the first heat exchange section 214 does not flow through the liquid cooling device 130, but flows directly to the second heat exchange section 224 through the second valve 320.

[0045] Preferably, during defrosting, the battery 1331 cluster requires heating, and the system defrosting needs to switch to heating. Specifically, the refrigerant is compressed by the compressor 110 to achieve a high-temperature overheated state, and is discharged from the compressor 110 to flow to the four-way valve 120. At this time, the four-way valve 120 does not operate, ensuring that the high-temperature and high-pressure gaseous refrigerant flows to the first condensation section 213 in the first branch 210 to achieve a transformation from high-temperature gas to high-temperature liquid; the refrigerant then flows to the first heat exchange section 214; the high-temperature liquid refrigerant flowing to the first heat exchange section 214 exchanges heat with the low-temperature gaseous refrigerant in the second heat exchange section 224, and performs Secondary subcooling; then flows out and flows to the second throttling element 420. At present, the second throttling element 420 throttles and reduces the pressure, the second valve 320 is opened, and the liquid cooling throttling elements 131 in each liquid cooling device 130 are closed: after the refrigerant flows through the second valve 320, it flows to the second heat exchange section 224. At this time, the refrigerant is in the state of low-temperature and low-pressure liquid refrigerant, and flows to the four-way valve 120 and electric heating. After the electric heating is turned on, the refrigerant undergoes a phase change from liquid to gas, and then returns to the compressor 110.

[0046] Furthermore, the direct cooling heat pump air conditioning system also includes: 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 condensation section 223 and the second heat exchange section 224; the fourth valve 340 is connected in parallel to the second branch 220, and one end of the fourth valve 340 is connected to the port A221 and between the second condensation section 223, and the other end of the fourth valve 340 is connected to between the third valve 330 and the second heat exchange section 224.

[0047] Specifically, by setting 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 passing through the four-way valve 120 and flowing to the second branch 220 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 condensation section 223; when the third valve 330 is closed and the fourth valve 340 is opened, the refrigerant flowing through the second branch 220 does not flow through the third valve 330 and the second condensation section 223, but flows through the fourth valve 340 and is directly connected to the four-way valve 120.

[0048] Furthermore, the direct cooling heat pump air conditioning system further includes: a heating device 140, and the heating device 140 is connected between the air intake port and the third valve port.

[0049] Specifically, when the direct cooling heat pump air conditioning system is in heating operation, a defrosting design is performed: when the system receives a defrosting instruction, the present invention does not need to release heat through the cold plate 1332, and defrosting can be achieved by setting a heating device 140 to avoid affecting the running battery 1331.

[0050] Furthermore, the direct cooling heat pump air conditioning system also includes: 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; the gas-liquid separator 160 is connected between the air intake port and the heating device 140 .

[0051] Specifically, the oil separator 150 is used to separate the gas and oil of the direct cooling heat pump air-conditioning system. Specifically, the oil separator 150 separates the compressor 110 oil from the high-temperature and high-pressure steam discharged from 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", it is easy to cause damage to the compressor 110. Therefore, a gas-liquid separator 160 for separating gas and liquid is added to 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, which plays a buffering role for the gas-liquid separator 160.

[0052] Furthermore, the direct cooling heat pump air conditioning system also includes: a bypass pipe 230 and a third filter 231, one end of the bypass pipe 230 is connected to the oil separator 150, and the other end of the bypass pipe 230 is connected to the air intake port; the third filter 231 is connected in series to the bypass pipe 230.

[0053] Specifically, the high-temperature and high-pressure steam refrigerant compressed by the compressor 110 brings out a small amount of compressor 110 oil. After flowing through the oil separator 150, the gas and oil are separated due to its special structure. The oil is affected by gravity and flows to the bottom of the oil separator 150. Under the suction of the compressor 110, the oil flows through the third filter 231 and the capillary tube of the bypass line 230, and then returns to the compressor 110.

[0054] Furthermore, the direct cooling heat pump air conditioning system further includes: a condenser 170 and a plate heat exchanger 180 , wherein the condenser 170 is provided with a first condensation section 213 and a second condensation section 223 ; and the plate heat exchanger 180 is provided with a first heat exchange section 214 and a second heat exchange section 224 .

[0055] Specifically, the structure of the first condensation section 213 and the second condensation section 223 is realized by the condenser 170, so that the overall structure of the direct cooling heat pump air-conditioning system is simpler; because the optimal working environment temperature of the battery cell is about 25-30°C, and the cold plate 1332 has limited pressure resistance, the high-pressure and high-temperature gaseous refrigerant discharged by the compressor 110 needs to be further cooled, so a pre-cooling design is performed, specifically: the double flow channel, small branch and bypass design of the condenser 170 are designed to meet the temperature drop of the high-temperature gaseous refrigerant during conventional heating, so that the temperature of the refrigerant entering the cold plate 1332 does not exceed 35°C, so that the battery 1331 can work in the optimal working range of 20-30°C; during ultra-low temperature heating (that is, heating under severe conditions), considering the low temperature of the outer ring, if the condenser 170 branch is used for cooling, it is easy to condense, so in combination with the plate heat exchanger 180, the temperature difference between the two ends of evaporation and condensation is used for heat exchange, thereby achieving exhaust gas cooling.

[0056] 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 can realize heat exchange through 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 exchange heat; the high-pressure liquid refrigerant at the outlet of the condenser 170 cannot change phase, so the temperature is reduced, and secondary supercooling is achieved to improve energy efficiency; the gas-liquid two-phase refrigerant at the outlet of the cold plate 1332 changes phase completely into gas, and even overheats, to ensure that the refrigerant entering the compressor 110 does not contain liquid, and prevent liquid hammer. In other words, in the present invention, an even temperature design is carried out, the cold plate 1332 is not overheated, the heat exchange outlet is a gas-liquid mixture, and the plate heat exchanger 180 and its pipeline design are used to achieve overheating.

[0057] Preferably, in order to ensure uniform heat exchange of cold plate 1332, the heat exchange of cold plate 1332 should be basically latent heat, that is, phase change heat exchange, without overheating or with very small overheating. At this time, throttling control can be achieved through throttling element control to ensure that the liquid refrigerant entering the cold plate 1332 is not completely evaporated. Whether the cold plate 1332 is overheated can be determined by the superheat; and because the outlet of cold plate 1332 is not overheated, in order to avoid liquid compression, an overheating section needs to be added after the cold plate 1332 (that is, using the plate heat exchanger 180 to transfer the high temperature of the condensation outlet to the low temperature liquid refrigerant at the outlet of the cold plate 1332 to achieve evaporation superheating).

[0058] In a specific embodiment, when the direct cooling heat pump air conditioning system is in cooling operation, the refrigerant flows as follows: Figure 2As shown, the unit receives the start-up instruction, the refrigerant is compressed by the compressor 110, achieves a high-temperature superheated state, and is discharged from the compressor 110 to flow to the oil separator 150 and the four-way valve 120. At this time, the four-way valve 120 does not operate, ensuring that the high-temperature and high-pressure gaseous refrigerant flows to the first condensation section 213 in the condenser 170. The fan cooperates to enhance the phase change heat of the refrigerant in the condenser 170, and realizes the transformation from high-temperature gas to high-temperature liquid. In order to ensure performance, the condenser 170 is optimized and a supercooling section (that is, the first condensation section 213) is added, so that the refrigerant 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 after flowing to the plate heat exchanger 180 exchanges heat with the low-temperature gas-liquid refrigerant at the outlet of the other side of the plate heat exchanger 180 (that is, the second heat exchange section 224 side) for secondary supercooling; then it flows out of the plate heat exchanger 180 and flows to the second filter 421 and the second throttling element 420. At present, the second throttling element 420 is not in action, the valve step is fully opened, the second valve 320 is closed, and the refrigerant flows to After the battery 1331 cluster is divided into several groups, it flows to the cold plate 1332; each group of the secondary battery 1331 has a liquid cooling throttling element 131, and the refrigerant first passes through the liquid cooling throttling element 131 for throttling, and the refrigerant state changes from high-pressure and high-temperature liquid to low-temperature and low-pressure liquid (flash will cause the evaporation temperature to decrease), and then the liquid distributor 132 divides the third-level branch to distribute multiple refrigerant flows to the battery 1331 cold plate 1332 for heat exchange; the low-temperature and low-pressure liquid refrigerant absorbs the heat of the battery 1331 and undergoes a phase change, so that the refrigerant state at the outlet of the cold plate 1332 after heat exchange is a gas-liquid mixture. The refrigerant passes through the collector, gathers together, and flows to the plate heat exchanger 180. The first throttling element 410 is closed, and the low-temperature and low-pressure gas-liquid mixed refrigerant from the outlet of the cold plate 1332 exchanges heat with the high-temperature liquid refrigerant from the outlet of the condenser 170 on the other side of the plate heat exchanger 180. Due to the absorption of heat, the refrigerant is now in a low-pressure gaseous refrigerant at room temperature, and then flows through the four-way valve 120, the electric heating device 140, the gas-liquid separator 160, and finally returns to the compressor 110; wherein the fourth valve 340 and the electric heating device 140 are closed.

[0059] When the direct cooling heat pump air conditioning system is in normal heating operation, the refrigerant flows as follows Figure 3As shown, the unit receives a start-up instruction, and the refrigerant is compressed by the compressor 110 to achieve a high-temperature overheating state, and is discharged from the compressor 110 to flow 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 condensation section 223 in the condenser 170, realizing the transformation from high-temperature gas to medium-temperature gas, wherein 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 after flowing to the plate heat exchanger 180 does not exchange heat with the low-temperature liquid refrigerant at the outlet of the other side of the plate heat exchanger 180 (that is, the first heat exchange section 214 side), wherein the first throttling element 410 is opened, and most of the gaseous refrigerant flows; the second The valve 320 is closed, and the refrigerant flows to the battery cluster 1331 and then flows to the cold plate 1332 in stages through the collecting pipe 134; the refrigerant undergoes a phase change in the cold plate 1332, so that the refrigerant at the outlet of the cold plate 1332 is in a gas-liquid state, and then flows through the liquid separator 132, and each group of liquid-cooled throttling elements 131 is fully opened, and after being collected together, it flows to the second throttling element 420 for throttling and pressure reduction; throttling and pressure reduction flashes, and the refrigerant temperature decreases. At this time, the refrigerant is in a low-temperature and low-pressure liquid refrigerant; it flows through the first valve 310, does not flow through the first heat exchange section 214, and directly flows to the condenser 170 for heat exchange; the refrigerant after heat exchange is in a low-temperature and low-pressure gaseous refrigerant, and 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.

[0060] When the direct cooling heat pump air conditioning system is in the bad heating operation, the refrigerant flows as follows Figure 4As shown, the unit receives a start-up instruction, and the refrigerant is compressed by the compressor 110 to achieve a high-temperature overheating state, and is discharged from the compressor 110 to flow 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 and does not flow through the second condensation section 223 in the condenser 170, thereby realizing the transformation from high-temperature gas to medium-temperature gas, wherein 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 (that is, the first heat exchange section 214 side), wherein the first throttling element 410 is opened as needed to ensure that the refrigerant passing through the outlet of the plate heat exchanger 180 is in a gaseous state; the refrigerant flows to the battery 1331 cluster and is then collected by the collector The flow tube 134 flows to the cold plate 1332 in stages; the refrigerant undergoes a phase change in the cold plate 1332, so that the refrigerant at the outlet of the cold plate 1332 is in a gas-liquid state, and then flows through the liquid separator 132, and each group of liquid-cooled throttling elements 131 is fully opened, and after being collected together, it flows to the second throttling element 420 for throttling and pressure reduction; throttling and pressure reduction occur flashes, and the refrigerant temperature decreases. At this time, the refrigerant is in a low-temperature and low-pressure liquid refrigerant; the second valve 320 is closed, and 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 in a low-temperature and low-pressure gaseous refrigerant, and 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.

[0061] When the direct cooling heat pump air conditioning system is in defrosting operation, the refrigerant flows as follows Figure 5 As shown, the unit receives a defrost instruction, and the refrigerant is compressed by the compressor 110 to achieve a high-temperature overheated state, and is discharged from the compressor to flow to the oil separator 150 and the four-way valve 120. At this time, the four-way valve 120 does not operate, ensuring that the high-temperature and high-pressure gaseous refrigerant flows to the condenser 170. The fan cooperates to enhance the phase change heat of the refrigerant in the condenser 170, and realizes the transformation 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 flowing to the plate heat exchanger exchanges heat with the low-temperature gaseous refrigerant at the outlet of the other side of the plate heat exchanger (that is, the second heat exchange section 224). , for secondary supercooling; then it flows out of the plate heat exchanger 180, flows to the second filter 421 and the second throttling element 420, the current second throttling element 420 throttling and reducing the pressure, the second valve 320 is opened, and the liquid cooling throttling element 131 of the battery cluster 1331 is closed: after the refrigerant flows through the second valve 320, it flows to the plate heat exchanger, at which time the refrigerant is in the state of low temperature and low pressure liquid refrigerant, flows to the first throttling element, the valve step is fully opened, flows to the four-way valve 120 and the electric heating device 140, after the electric heating device 140 is turned on, the refrigerant undergoes a phase change, liquid → gas, and then flows through the gas-liquid separator 160 back to the compressor 110.

[0062] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A direct cooling heat pump air conditioning system for an energy storage temperature control system, characterized in that: 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), wherein 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 the exhaust port of the compressor (110) is connected to the first valve port, the intake port of the compressor (110) is connected to the third valve port, the first end (211) is connected to the second valve port, and the port A (221) is connected to the fourth valve port; The first branch (210) is provided with a first condensing section (213) and a first heat exchanging section (214) connected in series, and the first heat exchanging section (214) is arranged between the first condensing section (213) and the second end (212); The second branch (220) is connected in series with a second condensing section (223) and a second heat exchange section (224), and the second heat exchange section (224) is arranged between the second condensing section (223) and the port B (222).

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

3. The direct cooling heat pump air conditioning system according to any one of claims 1 to 2, characterized in that: The liquid cooling device (130) comprises: A liquid-cooled throttling element (131), a liquid distributor (132) and a plurality of liquid-cooled components (133); The liquid-cooling throttling element (131) is connected to the second end (212), the liquid-cooling component (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 component (133); The plurality of liquid cooling components (133) are arranged in parallel.

4. The direct cooling heat pump air conditioning system according to claim 1, characterized in that: The direct cooling heat pump air conditioning system also includes: A first valve (310), the first valve (310) being connected in parallel to two ends of the first heat exchange section (214); A first throttling element (410), the first throttling element (410) being connected in parallel to two ends of the second heat exchange section (224); A second throttling element (420), wherein the second throttling element (420) is 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).

5. The direct cooling heat pump air conditioning system according to claim 4, characterized in that: The direct cooling heat pump air conditioning system also includes: 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).

6. The direct cooling heat pump air conditioning system according to claim 1, characterized in that: The direct cooling heat pump air conditioning system also includes: a third valve (330), the third valve (330) being arranged on the second branch (220), and the third valve (330) being arranged between the second condensing section (223) and the second heat exchanging section (224); A fourth valve (340), the 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 condensation 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).

7. The direct cooling heat pump air conditioning system according to claim 1, characterized in that: The direct cooling heat pump air conditioning system also includes: A heating device (140) is connected between the air intake port and the third valve port.

8. The direct cooling heat pump air conditioning system according to claim 7, characterized in that: The direct cooling heat pump air conditioning system also includes: an oil separator (150), the oil separator (150) being connected between the exhaust port and the first valve port; A gas-liquid separator (160), wherein the gas-liquid separator (160) is connected between the air intake port and the heating device (140).

9. The direct cooling heat pump air conditioning system according to claim 8, characterized in that: The direct cooling heat pump air conditioning system also includes: a bypass pipeline (230), one end of the bypass pipeline (230) being connected to the oil separator (150), and the other end of the bypass pipeline (230) being connected to the air intake port; A third filter (231), the third filter (231) is connected in series to the bypass line (230).

10. The direct cooling heat pump air conditioning system according to claim 1, characterized in that: The direct cooling heat pump air conditioning system also includes: A condenser (170), wherein the condenser (170) is provided with the first condensation section (213) and the second condensation section (223); A plate heat exchanger (180), wherein the plate heat exchanger (180) is provided with the first heat exchange section (214) and the second heat exchange section (224).

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