Air conditioning system and control method thereof

Abstract

The invention provides an air conditioning system and a control method thereof.The air conditioning system comprises a refrigerant compression cycle, a secondary refrigerant cycle and an intermediate heat exchanger, the refrigerant compression cycle comprises an indoor heat exchanger, and the secondary refrigerant cycle comprises an indoor temperature adjusting heat exchanger, solar equipment with a heat collecting pipe, a bypass pipeline and a water pump used for driving a secondary refrigerant to circularly flow; the bypass pipeline is connected with the heat collecting pipe in parallel, the flow of a secondary refrigerant in the bypass pipeline and the heat collecting pipe can enable the secondary refrigerant in the secondary refrigerant heat exchange pipe to exchange heat with a refrigerant in the refrigerant heat exchange pipe, and the secondary refrigerant in the secondary refrigerant overflowing pipe does not exchange heat with the refrigerant in the refrigerant heat exchange pipe. The secondary refrigerant can be switched between the bypass pipeline and the heat collecting pipe or distribute the flow, fine adjustment of the indoor temperature adjusting heat exchanger on the air outlet temperature is achieved, the defects that in the related technology, due to the fact that part of operation frequency points of a compressor are shielded, the air outlet temperature changes suddenly, and the room temperature fluctuation is large are effectively overcome, and the service life of the indoor temperature adjusting heat exchanger is prolonged. And the comfort of the user is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of air conditioning, and in particular relates to an air conditioning system and a control method thereof. Background Art

[0002] Most of the air-conditioning equipment on the market today need to shield some of the compressor's operating frequency points due to compressor problems, unreasonable piping design, or resonance problems of various components. This causes sudden changes in the air outlet temperature during daily operation of the air-conditioning equipment. Even if the compressor shields too many frequency points, the air-conditioning equipment cannot achieve fine adjustment, causing the room temperature to fluctuate, affecting user comfort. Summary of the invention

[0003] Therefore, the present invention provides an air-conditioning system and a control method thereof, which can overcome the technical problems in the related art that some operating frequency points of the compressor in the air-conditioning system are shielded, resulting in sudden changes in the air outlet temperature during the operation of the air-conditioning system, and even the air-conditioning cannot be finely adjusted, resulting in room temperature fluctuations and reducing user comfort.

[0004] In order to solve the above problems, the present invention provides an air-conditioning system, including a refrigerant compression cycle, a secondary coolant cycle and an intermediate heat exchanger, wherein the refrigerant compression cycle includes an indoor heat exchanger, and when the refrigerant compression cycle operates in a refrigeration condition, the refrigerant inlet pipe of the indoor heat exchanger is a first pipe, and the secondary coolant cycle includes an indoor temperature-regulating heat exchanger, a solar energy device, a bypass pipeline and a water pump for driving the secondary coolant to circulate, and the indoor temperature-regulating heat exchanger is located at the outlet side of the indoor heat exchanger to adjust the temperature of the outlet airflow of the indoor heat exchanger, and the solar energy device includes The heat collecting tube, the bypass pipeline is connected in parallel with the heat collecting tube, the flow rate of the refrigerant in the bypass pipeline and the heat collecting tube can be controlled and adjusted, the refrigerant inlet pipe of the indoor temperature-regulating heat exchanger is the second pipe, the intermediate heat exchanger has a refrigerant heat exchange tube connected in series in the first tube and a refrigerant heat exchange tube and a refrigerant flow tube that can be selectively connected in series in the second tube, wherein the refrigerant in the refrigerant heat exchange tube can exchange heat with the refrigerant in the refrigerant heat exchange tube, and the refrigerant in the refrigerant flow tube does not exchange heat with the refrigerant in the refrigerant heat exchange tube.

[0005] In some embodiments, the refrigerant circulation also includes a three-way flow valve, the inlet of the three-way flow valve is connected to the outlet of the indoor temperature-control heat exchanger, the first outlet of the three-way flow valve is connected to the inlet of the heat collecting pipe, the second outlet of the three-way flow valve is connected to the bypass pipeline, and flow adjustment valve cores are provided in the first outlet and the second outlet.

[0006] In some embodiments, the solar energy device further comprises a photovoltaic panel, and the photovoltaic panel is thermally coupled to the thermal collecting tube.

[0007] In some embodiments, the refrigerant compression cycle has a compressor and an outdoor heat exchanger, the compressor is an air-supply and enthalpy-increasing compressor, and when the refrigerant compression cycle operates in a refrigeration condition, the refrigerant outlet pipe of the outdoor heat exchanger is a third pipe, and the refrigerant compression cycle also includes a flash evaporator, an end of the first pipe away from the indoor heat exchanger and an end of the third pipe away from the outdoor heat exchanger are both in the flash evaporator, and the air outlet pipe of the flash evaporator is connected to the air supply port of the compressor, a first throttling element is also connected in series to the first pipe and the first throttling element is located on the side of the refrigerant heat exchange pipe away from the indoor heat exchanger, and a second throttling element is connected in series to the third pipe.

[0008] In some embodiments, the air conditioning system further includes a four-way reversing valve to achieve flow direction switching of the refrigerant in the refrigerant compression cycle between a cooling condition and a heating condition.

[0009] The present invention also provides a control method for the air conditioning system as described above, comprising the following steps:

[0010] Get the operation instructions of the air conditioning system;

[0011] According to the operating instruction, the operating mode of the refrigerant compression cycle is controlled, and one of the refrigerant heat exchange tube and the refrigerant flow tube is controlled to be connected in series in the second tube, and the flow rate of the refrigerant in the bypass pipeline and the heat collecting tube is controlled.

[0012] In some embodiments, when the operation instruction is a dual evaporation temperature refrigeration mode, according to the operation instruction, controlling the operation mode of the refrigerant compression cycle, controlling one of the brine heat exchange tube and the brine flow tube to be connected in series in the second tube, and controlling the flow rate of the brine in the bypass pipeline and the heat collecting tube specifically include:

[0013] Control the refrigerant compression cycle to operate the refrigeration condition and control the refrigerant heat exchange tube to be connected in series in the second tube, and obtain the set temperature value and the indoor temperature value and indoor humidity value;

[0014] Determine the evaporation temperature of the indoor heat exchanger according to the set temperature value, the indoor temperature value, and the indoor humidity value;

[0015] The rotation speed of the water pump and the flow rate of the coolant in the bypass pipeline or the heat collecting pipe are controlled and adjusted according to the temperature value of the coolant after the indoor temperature-regulating heat exchanger and the evaporation temperature of the indoor heat exchanger.

[0016] In some embodiments, when the operation instruction is a temperature and humidity control mode, according to the operation instruction, controlling the operation mode of the refrigerant compression cycle, controlling one of the brine heat exchange tube and the brine flow tube to be connected in series in the second tube, and controlling the flow rate of the brine in the bypass pipeline and the heat collecting tube specifically include:

[0017] Control the refrigerant compression cycle to operate the refrigeration condition and control the coolant flow pipe to be connected in series in the second pipe, and obtain the set temperature value and the indoor temperature value and indoor humidity value;

[0018] Determine the evaporation temperature of the indoor heat exchanger according to the set temperature value, the indoor temperature value, and the indoor humidity value;

[0019] The rotation speed of the water pump and the flow rate of the coolant in the bypass pipeline or the heat collecting pipe are controlled and adjusted according to the outlet air temperature of the indoor temperature-regulating heat exchanger and the indoor temperature value.

[0020] In some embodiments, when the operation instruction is a heating mode, according to the operation instruction, controlling the operation mode of the refrigerant compression cycle, controlling one of the brine heat exchange tube and the brine flow tube to be connected in series in the second tube, and controlling the flow rate of the brine in the bypass pipeline and the heat collecting tube specifically include:

[0021] Control the refrigerant compression cycle to operate in a heating condition and control the refrigerant heat exchange tube to be connected in series in the second tube, and obtain a set temperature value and an indoor temperature value;

[0022] Determine the condensing temperature of the indoor heat exchanger according to the set temperature value and the indoor temperature value;

[0023] The rotation speed of the water pump and the flow rate of the coolant in the bypass pipeline or the heat collecting pipe are controlled and adjusted according to the outlet air temperature of the indoor temperature-regulating heat exchanger.

[0024] In some embodiments, when the operation instruction is a dual evaporation temperature cooling mode, after adjusting the rotation speed of the water pump and the flow rate of the refrigerant in the bypass pipe or the heat collecting pipe according to the temperature value of the refrigerant after the indoor temperature-regulating heat exchanger and the evaporation temperature of the indoor heat exchanger, it also includes fine-tuning the flow rate of the refrigerant in the bypass pipe or the heat collecting pipe according to the temperature difference of the refrigerant entering and leaving the indoor temperature-regulating heat exchanger and the evaporation temperature of the indoor heat exchanger; or,

[0025] When the operation instruction is the heating mode, after adjusting the rotation speed of the water pump and the flow rate of the refrigerant in the bypass pipe or the heat collecting pipe according to the outlet air temperature control of the indoor temperature-regulating heat exchanger, it also includes fine-tuning the flow rate of the refrigerant in the bypass pipe or the heat collecting pipe according to the difference in evaporation temperatures between the indoor heat exchanger and the indoor temperature-regulating heat exchanger.

[0026] In some embodiments, when the operation instruction is a defrost mode, according to the operation instruction, controlling the operation mode of the refrigerant compression cycle, controlling one of the brine heat exchange tube and the brine flow tube to be connected in series in the second tube, and controlling the flow rate of the brine in the bypass pipeline and the heat collecting tube specifically include:

[0027] Controlling the refrigerant compression cycle to operate the refrigeration condition and obtaining the outer ring temperature;

[0028] When the outer ring temperature is higher than the preset temperature and the refrigerant temperature in the refrigerant flow tube is higher than the refrigerant temperature in the refrigerant heat exchange tube of the indoor heat exchanger, the refrigerant heat exchange tube is controlled to be connected in series in the second tube, and the water pump is controlled to operate.

[0029] The air conditioning system and control method thereof provided by the present invention have the following beneficial effects:

[0030] The intermediate heat exchanger is equipped with a refrigerant heat exchange tube connected in series in the first tube, a coolant heat exchange tube and a coolant flow tube that can be connected in series in the second tube, wherein the coolant heat exchange tube and the coolant flow tube can be selected to be connected in series in the second tube according to actual needs, so as to realize heat exchange between the coolant in the coolant cycle and the refrigerant in the refrigerant compression cycle. Since the indoor temperature-control heat exchanger is arranged on the air outlet side of the indoor heat exchanger, the cold / heat in the coolant can be used to further adjust the temperature of the outlet airflow after heat exchange by the indoor heat exchanger. At the same time, the coolant in the present invention can also switch or distribute the flow between the bypass pipeline and the heat collecting tube, so as to realize the fine adjustment of the outlet air temperature by the indoor temperature-control heat exchanger, effectively overcoming the shortcomings of the related technology such as sudden change of outlet air temperature and large fluctuation of room temperature caused by shielding of some operating frequency points of the compressor, thereby improving the comfort of users. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the implementation methods of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the implementation methods or the description of the prior art. The drawings described below are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0032] Figure 1is a schematic diagram of the system principle of the air conditioning system in an embodiment of the present invention;

[0033] Figure 2 yes Figure 1 A schematic diagram of the refrigerant (solid arrows) / coolant (hollow arrows) flow of the air-conditioning system in the dual evaporation temperature cooling mode, in which the coolant does not flow through the heat collecting tube, that is, the valve core at the first outlet of the three-way flow valve is cut off;

[0034] Figure 3 yes Figure 1 Schematic diagram of the refrigerant (solid arrows) / coolant (hollow arrows) circulation of the air-conditioning system in the temperature and humidity control mode;

[0035] Figure 4 yes Figure 1 The air conditioning system in FIG. 1 is a schematic diagram of the refrigerant (indicated by solid arrows) / coolant (indicated by hollow arrows) flow in the heating mode, in which the coolant does not flow through the heat collecting tube, that is, the valve core at the first outlet of the three-way flow valve is cut off;

[0036] Figure 5 yes Figure 1 A schematic diagram of the refrigerant (indicated by solid arrows) / coolant (indicated by hollow arrows) flow of the air-conditioning system in the defrosting mode, in which the coolant does not flow through the bypass line, that is, the valve core at the second outlet of the three-way flow valve is cut off;

[0037] Figure 6 It is a control flow diagram when the operation instruction received by the air-conditioning system of the present invention is a dual evaporating temperature cooling mode;

[0038] Figure 7 It is a control flow diagram when the operating instruction received by the air-conditioning system of the present invention is a temperature and humidity control mode;

[0039] Figure 8 is a schematic diagram of a control flow when the operating instruction received by the air-conditioning system of the present invention is a heating mode;

[0040] Fig. 9 It is a schematic diagram of a control flow when the operating instruction received by the air-conditioning system of the present invention is a defrost mode;

[0041] Fig.10 yes Figure 1 Schematic diagram of heat exchange state of internal flow path of intermediate heat exchanger in, wherein (a) shows the state that refrigerant flows in refrigerant heat exchange tube to exchange heat with refrigerant in refrigerant heat exchange tube, and (b) shows the state that refrigerant flows in refrigerant flow tube to avoid heat exchange with refrigerant in refrigerant heat exchange tube, and arrows in the figure show the flow direction of refrigerant and refrigerant.

[0042] The accompanying drawings are marked as follows:

[0043] 11. Indoor heat exchanger; 12. Flash evaporator; 13. Compressor; 14. Outdoor heat exchanger; 151. First throttling element; 152. Second throttling element; 16. Four-way reversing valve; 21. Indoor temperature-control heat exchanger; 22. Solar energy equipment; 221. Collecting tube; 222. Photovoltaic panel; 223. Solar energy controller; 23. Water pump; 24. Bypass pipeline; 25. Three-way flow valve; 3. Intermediate heat exchanger; 41. Temperature sensor; 42. Temperature and humidity sensor. DETAILED DESCRIPTION

[0044] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. 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.

[0045] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the devices or elements referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention. The directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0046] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90° or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0047] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0048] See also Figures 1 to 10 As shown, according to an embodiment of the present invention, an air conditioning system is provided, including a refrigerant compression cycle (not labeled in the figure), a secondary refrigerant cycle (not labeled in the figure) and an intermediate heat exchanger 3, wherein the refrigerant compression cycle includes an indoor heat exchanger 11, and when the refrigerant compression cycle operates in a cooling condition, the refrigerant inlet pipe of the indoor heat exchanger 11 is a first pipe (not labeled in the figure, it can be understood that when the refrigerant compression cycle operates in a heating condition, the first pipe will be used as a refrigerant outlet pipe), and the secondary refrigerant cycle includes an indoor temperature-regulating heat exchanger 21 , a solar device 22, a bypass pipe 24 and a water pump 23 for driving the circulation of the brine, the indoor temperature-adjusting heat exchanger 21 is located at the outlet side of the indoor heat exchanger 11 to adjust the temperature of the outlet airflow of the indoor heat exchanger 11, the solar device 22 includes a heat collecting pipe 221, the bypass pipe 24 is connected in parallel with the heat collecting pipe 221, the brine flow in the bypass pipe 24 and the heat collecting pipe 221 can be controlled and adjusted, the outlet of the water pump 23 and the inlet of the indoor temperature-adjusting heat exchanger 21 are connected through a second pipe (not shown in the figure) The intermediate heat exchanger 3 has a refrigerant heat exchange tube (not shown in the figure, not labeled) connected in series in the first tube, and a refrigerant heat exchange tube (not shown in the figure, not labeled) and a refrigerant flow tube (not shown in the figure, not labeled) that can be selectively connected in series in the second tube, wherein the refrigerant in the refrigerant heat exchange tube can exchange heat with the refrigerant in the refrigerant heat exchange tube, and the refrigerant in the refrigerant flow tube can exchange heat with the refrigerant in the refrigerant heat exchange tube. No heat exchange, specifically, the aforementioned coolant heat exchange tube and the refrigerant heat exchange tube are thermally coupled to each other, and the coolant flow tube is set in an area away from the aforementioned refrigerant heat exchange tube, specifically based on the fact that the cold or heat of the refrigerant will not be transferred to the coolant in the coolant flow tube. The aforementioned heat collecting tube 221 specifically adopts the solar energy utilization technology in the prior art to convert light energy into the heat of the coolant flowing therein. The present invention does not intend to improve the specific structure of the heat collecting tube 221, and conventional heat collecting tubes can be used for assembly. It can be understood that the aforementioned intermediate heat exchanger 3 can adopt a tube-in-tube heat exchanger in the specific implementation structure, which is simple and reliable.

[0049] In this technical solution, the intermediate heat exchanger 3 is equipped with a refrigerant heat exchange tube connected in series in the first tube, a coolant heat exchange tube and a coolant flow tube that can be connected in series in the second tube, wherein the coolant heat exchange tube and the coolant flow tube can be selected to be connected in series in the second tube according to actual needs, so as to realize the heat exchange between the coolant in the coolant cycle and the refrigerant in the refrigerant compression cycle. Since the indoor temperature-control heat exchanger 21 is arranged on the air outlet side of the indoor heat exchanger 11, the cold / heat in the coolant can be used to further adjust the temperature of the outlet airflow after heat exchange in the indoor heat exchanger 11. At the same time, the coolant in the present invention can also switch or distribute the flow between the bypass pipeline and the heat collecting tube, so as to realize the fine adjustment of the outlet air temperature by the indoor temperature-control heat exchanger 21, effectively overcoming the shortcomings of the related technology such as sudden change of outlet air temperature and large fluctuation of room temperature caused by shielding of some operating frequency points of the compressor, thereby improving the comfort of users.

[0050] It should be noted that, taking the refrigerant compression cycle in the refrigeration condition as an example, at this time, the indoor heat exchanger 11 acts as an evaporator to absorb indoor heat. When a certain operating frequency point of the compressor (the operating frequency point corresponding to the comfortable cooling temperature) is shielded, the evaporation temperature of the indoor heat exchanger 11 at this time may be low. If the outlet air temperature is not adjusted, the outlet air temperature will be low. After running for a period of time, the air-conditioning system receives corresponding temperature feedback and then adjusts the operating frequency point to continue running. However, the operating frequency point is still not a suitable frequency point. This will cause the indoor temperature to fluctuate up and down. By adopting the embodiment of the present invention, when the operating frequency point is higher than the suitable frequency point, a refrigerant can be used to transfer part of the cooling capacity of the refrigerant from the refrigerant compression cycle to the refrigerant cycle, and further transfer it to the heat collecting pipe 221 to absorb heat, thereby utilizing the solar The heat can be used to eliminate the excess cold in the refrigerant compression cycle, thereby achieving the temperature control purpose of the indoor temperature control heat exchanger 21, making the outlet air temperature at the set temperature, and improving comfort. In this process, the flow rate of the refrigerant in the aforementioned bypass pipe 24 or the heat collecting pipe 221 can be controlled according to the actual temperature control needs. Specifically, the more cold the amount needs to be reduced, the greater the flow rate into the heat collecting pipe 221 is controlled. When the evaporation temperature of the indoor heat exchanger 11 may be high due to the shielding of a certain operating frequency point of the compressor, the refrigerant heat exchange pipe can be used to transfer the cold in the refrigerant heat exchange pipe to the refrigerant circulation. At this time, the refrigerant is controlled not to flow in the heat collecting pipe 221, and the refrigerant circulation is formed from the bypass pipe 24. This objectively increases the heat exchange area of ​​the outlet air flow, improves the heat exchange effect, and is also conducive to reducing the outlet air temperature at the same evaporation temperature. The fine temperature control principle of the refrigerant compression cycle under heating conditions is roughly similar to that under the aforementioned cooling conditions, and will not be repeated.

[0051] The flow distribution of the above-mentioned refrigerant circulation in the bypass pipeline 24 and the heat collecting pipe 221 can be carried out in a variety of ways. For example, corresponding electromagnetic flow valves are respectively arranged on the bypass pipeline 24 and the heat collecting pipe 221, and the distribution of the refrigerant flow is achieved by controlling the on-off and opening of the electromagnetic flow valves on the corresponding pipelines. In a preferred embodiment, the refrigerant circulation also includes a three-way flow valve 25, the inlet of the three-way flow valve 25 is connected to the outlet of the indoor temperature control heat exchanger 21, the first outlet of the three-way flow valve 25 is connected to the inlet of the heat collecting pipe 221, the second outlet of the three-way flow valve 25 is connected to the bypass pipeline 24, and the first outlet and the second outlet are both provided with flow adjustment valve cores (not shown in the figure).

[0052] In this technical solution, a three-way flow valve 25 with an integrated flow regulating valve core is used to match and control the flow of the refrigerant in the Pantone pipeline 24 and the heat collecting pipe 221, which can simplify the connection of the pipelines.

[0053] As a specific embodiment, the solar device 22 also includes a photovoltaic panel 222, and the photovoltaic panel 222 is thermally coupled to the heat collecting tube 221, so that the coolant in the coolant cycle can be used to further cool the photovoltaic panel 222 after heat exchange with the refrigerant at the intermediate heat exchanger 3, thereby improving the power generation efficiency of the photovoltaic panel 222. It can be understood that when cooling the photovoltaic panel 222, the refrigerant compression cycle should be ensured to operate in a refrigeration condition, and the coolant heat exchange tube is connected in series in the second tube. The aforementioned solar device 22 also includes a corresponding solar controller to be able to store or transmit the power generation of the photovoltaic panel 222 to the air conditioning system (air conditioner) for use.

[0054] See Fig.10 As shown, the brine heat exchange tube and the brine flow tube in the intermediate heat exchanger 3 realize the circulation control of the brine by setting a switching valve component (such as a controllably switchable three-way valve) at the gathering position of the two tubes, wherein the brine heat exchange tube and the refrigerant heat exchange tube are thermally coupled to each other to form a heat exchange structure, and the brine flow tube is far away from the refrigerant heat exchange tube to prevent heat exchange between the two. It can be understood that the aforementioned brine heat exchange tube and refrigerant heat exchange tube can be provided in multiples respectively to improve the heat exchange efficiency and heat exchange effect between the two.

[0055] See Figure 1As shown, the refrigerant compression cycle has a compressor 13 and an outdoor heat exchanger 14. The compressor 13 is an air-injection and enthalpy-increasing compressor, so as to improve the high-temperature refrigeration capacity and energy efficiency of the air-conditioning system. Specifically, when the refrigerant compression cycle is operating in a refrigeration condition, the refrigerant outlet pipe of the outdoor heat exchanger 14 is a third pipe. The refrigerant compression cycle also includes a flash evaporator 12. The end of the first pipe away from the indoor heat exchanger 11 and the end of the third pipe away from the outdoor heat exchanger 14 are both in the flash evaporator 12, and the air outlet pipe of the flash evaporator 12 is connected to the air-injection port of the compressor 13. A first throttling element 151 (for example, an electronic expansion valve) is also connected in series to the first pipe and the first throttling element 151 is located on the side of the refrigerant heat exchange pipe away from the indoor heat exchanger 11. A second throttling element 152 (for example, an electronic expansion valve) is connected in series to the third pipe.

[0056] In this technical solution, the flash evaporator 12 is provided to increase the enthalpy of the compressor 13 by replenishing air, thereby improving the high-temperature refrigeration capacity and system energy efficiency of the air-conditioning system.

[0057] In some embodiments, the air-conditioning system further includes a four-way reversing valve 16 to achieve flow switching of the refrigerant in the refrigerant compression cycle between cooling conditions and heating conditions, that is, the refrigerant compression cycle of the present invention has cooling conditions and heating conditions, thereby improving the working performance of the air-conditioning system of the present invention.

[0058] It can be understood that in order to make the air-conditioning system of the present invention more precise and intelligent in control, corresponding temperature and humidity sensors 42 or temperature sensors 41 are also provided on or near each relevant component to detect the temperature and temperature and humidity (temperature and humidity) of the setting location area.

[0059] According to an embodiment of the present invention, there is also provided a control method for the air conditioning system as described above, comprising the following steps:

[0060] Get the operation instructions of the air conditioning system;

[0061] According to the operating instructions, the operating mode of the refrigerant compression cycle is controlled, and one of the refrigerant heat exchange tube and the refrigerant flow tube is controlled to be connected in series in the second tube, and the flow rate of the refrigerant in the bypass pipe 24 and the heat collecting pipe 221 is controlled, so that the outlet air flow temperature can be more finely controlled according to different operating modes of the air-conditioning system.

[0062] See Figure 2As shown, when the operation instruction is a dual evaporation temperature refrigeration mode, according to the operation instruction, the operation mode of the refrigerant compression cycle is controlled, and one of the brine heat exchange tube and the brine flow tube is controlled to be connected in series in the second tube, and the flow rate of the brine in the bypass pipeline 24 and the heat collecting tube 221 is controlled, which specifically includes:

[0063] Control the refrigerant compression cycle to operate the refrigeration condition and control the brine heat exchange tube to be connected in series in the second tube, so that the brine in the brine cycle can form heat exchange with the refrigerant in the refrigerant compression cycle, thereby realizing the transfer of cooling capacity of the brine to the refrigerant, and obtaining the set temperature value, indoor temperature value, and indoor humidity value;

[0064] The evaporation temperature of the indoor heat exchanger 11 is determined according to the set temperature value, the indoor temperature value, and the indoor humidity value, so as to realize the first cooling and cooling of the indoor airflow. It can be understood that the evaporation temperature of the indoor heat exchanger 11 is adjusted to a suitable value according to the set temperature value, the indoor temperature value, and the indoor humidity value as a common knowledge in the art, and the present invention will not elaborate on it;

[0065] The rotation speed of the water pump 23 and the flow rate of the refrigerant in the bypass pipe 24 or the heat collecting pipe 221 are controlled and adjusted according to the temperature value of the refrigerant after the indoor temperature-regulating heat exchanger 21 and the evaporation temperature of the indoor heat exchanger 11. Specifically, when the excess cold needs to be reduced at the heat collecting pipe 221, the refrigerant is controlled to flow into the heat collecting pipe 221. The more cold needs to be reduced, the greater the flow rate into the heat collecting pipe 221. At the same time, the flow rate of the refrigerant entering the bypass pipe 24 is smaller or even completely cut off. Conversely, when the cold needs to be reduced at the heat collecting pipe 221, the refrigerant is controlled to be cut off from entering the heat collecting pipe 221, thereby achieving fine control of the outlet air temperature in the cooling mode. Furthermore, when running this mode, as a more optimal implementation method, the flow rate of the refrigerant in the bypass pipe 24 or the heat collecting pipe 221 is fine-tuned according to the temperature difference of the inlet and outlet refrigerants of the indoor temperature-control heat exchanger 21 and the evaporation temperature of the indoor heat exchanger 11, so as to further achieve fine adjustment of the outlet air flow temperature.

[0066] See Figure 3 As shown, when the operation instruction is the temperature and humidity control mode, according to the operation instruction, the operation mode of the refrigerant compression cycle is controlled, and one of the brine heat exchange tube and the brine flow tube is controlled to be connected in series in the second tube, and the flow rate of the brine in the bypass pipeline 24 and the heat collecting tube 221 is controlled, which specifically includes:

[0067] Control the refrigerant compression cycle to operate the refrigeration condition and control the coolant flow pipe to be connected in series in the second pipe, so as to use the outdoor temperature or the heat at the heat collecting pipe to heat the outlet air flow after the heat exchange of the indoor heat exchanger 11 at the indoor temperature regulating heat exchanger 21, and obtain the set temperature value and the indoor temperature value and indoor humidity value;

[0068] Determining the evaporation temperature of the indoor heat exchanger 11 according to the set temperature value, the indoor temperature value, and the indoor humidity value;

[0069] The rotation speed of the water pump 23 and the flow rate of the coolant in the bypass pipe 24 or the heat collecting pipe 221 are controlled and adjusted according to the outlet air temperature of the indoor temperature-regulating heat exchanger 21 and the indoor temperature value.

[0070] In this technical solution, the indoor heat exchanger 11 is used to cool, condense and dehumidify the indoor airflow, and the refrigerant absorbs the outdoor temperature or the heat collection temperature of the heat collection pipe 221, and then heats the outlet airflow after heat exchange with the indoor heat exchanger 11 at the indoor temperature-adjusting heat exchanger 21, so as to prevent the discomfort caused by the outlet airflow being too cold to the user and improve the user comfort. It can be understood that the lower the outlet airflow temperature of the indoor heat exchanger 11, the greater the flow rate of the refrigerant flowing into the heat collection pipe 221, and vice versa. The heating capacity of the indoor temperature-adjusting heat exchanger 21 depends on the distribution of the refrigerant in the bypass pipe 24 and the heat collection pipe 25.

[0071] See Figure 4 As shown, when the operation instruction is the heating mode, according to the operation instruction, the operation mode of the refrigerant compression cycle is controlled, and one of the brine heat exchange tube and the brine flow tube is controlled to be connected in series in the second tube, and the flow rate of the brine in the bypass pipeline 24 and the heat collecting tube 221 is controlled, which specifically includes:

[0072] The refrigerant compression cycle is controlled to operate in heating mode and the secondary coolant heat exchange tube is controlled to be connected in series in the second tube, and the set temperature value and the indoor temperature value are obtained. After the secondary coolant and the refrigerant exchange heat in the intermediate heat exchanger 3, the secondary coolant transfers part of the heat of the refrigerant to the indoor temperature-regulating heat exchanger 21, thereby performing secondary heating on the outlet airflow of the indoor heat exchanger 11 through the indoor temperature-regulating heat exchanger 21. The indoor temperature-regulating heat exchanger 21 objectively increases the heat exchange area.

[0073] Determining the condensing temperature of the indoor heat exchanger 11 according to the set temperature value and the indoor temperature value;

[0074] The rotation speed of the water pump 23 and the flow rate of the coolant in the bypass pipe 24 or the heat collecting pipe 221 are controlled and adjusted according to the outlet air temperature of the indoor temperature-regulating heat exchanger 21. Generally speaking, the temperature in the heat collecting pipe 211 is generally lower than the thermal temperature of the refrigerant at this time. Therefore, the coolant is controlled to cut off the flow into the heat collecting pipe 211 and form a circulation from the bypass pipe 24.

[0075] In this technical solution, after the coolant and the refrigerant exchange heat in the intermediate heat exchanger 3, the coolant transfers part of the heat of the refrigerant to the indoor temperature-regulating heat exchanger 21, thereby secondary heating the outlet air flow of the indoor heat exchanger 11 through the indoor temperature-regulating heat exchanger 21. The indoor temperature-regulating heat exchanger 21 objectively increases the heat exchange area.

[0076] Furthermore, during the operation of the heating mode, it also includes fine-tuning the flow rate of the refrigerant in the bypass pipe 24 or the heat collecting pipe 221 according to the difference in evaporation temperatures between the indoor heat exchanger 11 and the indoor temperature-regulating heat exchanger 21, so as to further achieve fine adjustment of the outlet air flow temperature.

[0077] See Figure 5 As shown, when the operation instruction is the defrost mode, according to the operation instruction, the operation mode of the refrigerant compression cycle is controlled, and one of the brine heat exchange tube and the brine flow tube is controlled to be connected in series in the second tube, and the flow rate of the brine in the bypass line 24 and the heat collecting tube 221 is controlled, which specifically includes:

[0078] Controlling the refrigerant compression cycle to operate the refrigeration condition and obtaining the outer ring temperature (i.e., the external environment temperature);

[0079] When the outer ring temperature is higher than the preset temperature (for example, 0°C) and the refrigerant temperature in the refrigerant flow tube is higher than the refrigerant temperature in the refrigerant heat exchange tube of the indoor heat exchanger 11 (this means that the heat of the refrigerant can be recycled), the refrigerant heat exchange tube is controlled to be connected in series in the second tube, and the water pump 23 is controlled to operate.

[0080] In this technical solution, when the air conditioning system is running in defrost mode, when the outer ring temperature is higher than the preset temperature and the coolant temperature is higher than the refrigerant temperature in the refrigerant heat exchange tube, the coolant heat exchange tube is controlled to be connected in series in the second tube, and then the coolant with higher temperature is used to heat the refrigerant with lower temperature, so as to compensate for the temperature drop on the indoor side, increase the suction temperature of the compressor, and prevent the occurrence of liquid in the compressor suction. At the same time, it can also increase the exhaust temperature of the compressor to a certain extent, thereby shortening the defrost time of the outdoor heat exchanger. It can be understood that when the outer ring temperature is lower than the aforementioned preset temperature or the coolant temperature is lower than the refrigerant temperature in the refrigerant heat exchange tube, it means that the coolant in the coolant cycle cannot form heat compensation for the refrigerant. At this time, the air conditioning system can run the conventional defrost mode, that is, there is no need to operate the water pump 23, and the coolant heat exchange tube is cut off from the circulation of the coolant.

[0081] It is easy for those skilled in the art to understand that, without conflict, the advantageous technical features of the above-mentioned methods can be freely combined and superimposed.

[0082] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention. The above description is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present invention. These improvements and variations should also be regarded as the protection scope of the present invention.

Claims

1. An air conditioning system, characterized in that: The invention comprises a refrigerant compression cycle, a coolant circulation and an intermediate heat exchanger (3), wherein the refrigerant compression cycle comprises an indoor heat exchanger (11), and when the refrigerant compression cycle operates in a refrigeration condition, the refrigerant inlet pipe of the indoor heat exchanger (11) is a first pipe, and the coolant circulation comprises an indoor temperature-adjusting heat exchanger (21), a solar energy device (22), a bypass pipeline (24) and a water pump (23) for driving the coolant circulation flow, wherein the indoor temperature-adjusting heat exchanger (21) is located at the outlet side of the indoor heat exchanger (11) to adjust the temperature of the outlet airflow of the indoor heat exchanger (11), and the solar energy device (22) comprises a heat collecting pipe ( 221), the bypass pipe (24) is connected in parallel with the heat collecting pipe (221), the flow rate of the refrigerant in the bypass pipe (24) and the heat collecting pipe (221) can be controlled and adjusted, the refrigerant inlet pipe of the indoor temperature-regulating heat exchanger (21) is the second pipe, the intermediate heat exchanger (3) has a refrigerant heat exchange pipe connected in series in the first pipe and a refrigerant heat exchange pipe and a refrigerant flow pipe that can be selectively connected in series in the second pipe, wherein the refrigerant in the refrigerant heat exchange pipe can exchange heat with the refrigerant in the refrigerant heat exchange pipe, and the refrigerant in the refrigerant flow pipe does not exchange heat with the refrigerant in the refrigerant heat exchange pipe.

2. The air conditioning system according to claim 1, characterized in that: The refrigerant circulation also includes a three-way flow valve (25), the inlet of the three-way flow valve (25) is connected to the outlet of the indoor temperature-regulating heat exchanger (21), the first outlet of the three-way flow valve (25) is connected to the inlet of the heat collecting pipe (221), the second outlet of the three-way flow valve (25) is connected to the bypass pipeline (24), and flow regulating valve cores are provided in the first outlet and the second outlet.

3. The air conditioning system according to claim 1, characterized in that: The solar energy device (22) further comprises a photovoltaic panel (222), and the photovoltaic panel (222) is thermally coupled to the heat collecting tube (221).

4. The air conditioning system according to claim 1, characterized in that: The refrigerant compression cycle comprises a compressor (13) and an outdoor heat exchanger (14); the compressor (13) is an air replenishing and enthalpy increasing compressor; when the refrigerant compression cycle is operating in a refrigeration condition, the refrigerant outlet pipe of the outdoor heat exchanger (14) is a third pipe; the refrigerant compression cycle also comprises a flash evaporator (12); an end of the first pipe away from the indoor heat exchanger (11) and an end of the third pipe away from the outdoor heat exchanger (14) are both located in the flash evaporator (12); and an air outlet pipe of the flash evaporator (12) is connected to an air replenishing port of the compressor (13); a first throttling element (151) is also connected in series to the first pipe and the first throttling element (151) is located on a side of the refrigerant heat exchange pipe away from the indoor heat exchanger (11); and a second throttling element (152) is connected in series to the third pipe.

5. The air conditioning system according to claim 4, characterized in that: It also includes a four-way reversing valve (16) to achieve flow direction switching of the refrigerant in the refrigerant compression cycle between a cooling condition and a heating condition.

6. A method for controlling an air conditioning system according to any one of claims 1 to 5, characterized in that: The steps include: Get the operation instructions of the air conditioning system; According to the operating instruction, the operating mode of the refrigerant compression cycle is controlled, and one of the refrigerant heat exchange tube and the refrigerant flow tube is controlled to be connected in series in the second tube, and the flow rate of the refrigerant in the bypass pipeline (24) and the heat collecting tube (221) is controlled.

7. The control method according to claim 6, characterized in that: When the operation instruction is a dual evaporation temperature refrigeration mode, according to the operation instruction, controlling the operation mode of the refrigerant compression cycle, controlling one of the brine heat exchange tube and the brine flow tube to be connected in series in the second tube, and controlling the flow rate of the brine in the bypass pipeline (24) and the heat collecting tube (221) specifically include: Control the refrigerant compression cycle to operate the refrigeration condition and control the refrigerant heat exchange tube to be connected in series in the second tube, and obtain the set temperature value and the indoor temperature value and indoor humidity value; Determining the evaporation temperature of the indoor heat exchanger (11) according to the set temperature value, the indoor temperature value, and the indoor humidity value; The rotation speed of the water pump (23) and the flow rate of the refrigerant in the bypass pipeline (24) or the heat collecting pipe (221) are controlled and adjusted according to the temperature value of the refrigerant after the indoor temperature-regulating heat exchanger (21) and the evaporation temperature of the indoor heat exchanger (11).

8. The control method according to claim 6, characterized in that: When the operation instruction is a temperature and humidity control mode, according to the operation instruction, controlling the operation mode of the refrigerant compression cycle, controlling one of the brine heat exchange tube and the brine flow tube to be connected in series in the second tube, and controlling the flow rate of the brine in the bypass pipeline (24) and the heat collecting tube (221) specifically include: Control the refrigerant compression cycle to operate the refrigeration condition and control the coolant flow pipe to be connected in series in the second pipe, and obtain the set temperature value and the indoor temperature value and indoor humidity value; Determining the evaporation temperature of the indoor heat exchanger (11) according to the set temperature value, the indoor temperature value, and the indoor humidity value; The rotation speed of the water pump (23) and the flow rate of the coolant in the bypass pipeline (24) or the heat collecting pipe (221) are controlled and adjusted according to the outlet air temperature of the indoor temperature regulating heat exchanger (21) and the indoor temperature value.

9. The control method according to claim 6, characterized in that: When the operation instruction is a heating mode, according to the operation instruction, controlling the operation mode of the refrigerant compression cycle, controlling one of the brine heat exchange tube and the brine flow tube to be connected in series in the second tube, and controlling the flow rate of the brine in the bypass pipeline (24) and the heat collecting tube (221) specifically include: Control the refrigerant compression cycle to operate in a heating condition and control the refrigerant heat exchange tube to be connected in series in the second tube, and obtain a set temperature value and an indoor temperature value; Determining the condensing temperature of the indoor heat exchanger (11) according to the set temperature value and the indoor temperature value; The rotation speed of the water pump (23) and the flow rate of the coolant in the bypass pipeline (24) or the heat collecting pipe (221) are controlled and adjusted according to the outlet air temperature of the indoor temperature-regulating heat exchanger (21).

10. The control method according to claim 7 or 9, characterized in that: When the operation instruction is a dual evaporation temperature refrigeration mode, after adjusting the rotation speed of the water pump (23) and the flow rate of the refrigerant in the bypass pipe (24) or the heat collecting pipe (221) according to the temperature value of the refrigerant after the indoor temperature-adjusting heat exchanger (21) and the evaporation temperature of the indoor heat exchanger (11), the method further includes finely adjusting the flow rate of the refrigerant in the bypass pipe (24) or the heat collecting pipe (221) according to the temperature difference of the refrigerant entering and exiting the indoor temperature-adjusting heat exchanger (21) and the evaporation temperature of the indoor heat exchanger (11); or, When the operation instruction is a heating mode, after adjusting the rotation speed of the water pump (23) and the flow rate of the refrigerant in the bypass pipe (24) or the heat collecting pipe (221) according to the outlet air temperature control of the indoor temperature-regulating heat exchanger (21), it also includes finely adjusting the flow rate of the refrigerant in the bypass pipe (24) or the heat collecting pipe (221) according to the difference in evaporation temperatures between the indoor heat exchanger (11) and the indoor temperature-regulating heat exchanger (21).

11. The control method according to claim 6, characterized in that: When the operation instruction is a defrost mode, according to the operation instruction, controlling the operation mode of the refrigerant compression cycle, controlling one of the brine heat exchange tube and the brine flow tube to be connected in series in the second tube, and controlling the flow rate of the brine in the bypass pipeline (24) and the heat collecting tube (221) specifically include: Controlling the refrigerant compression cycle to operate the refrigeration condition and obtaining the outer ring temperature; When the outer ring temperature is higher than the preset temperature and the refrigerant temperature in the refrigerant flow pipe is higher than the refrigerant temperature in the refrigerant heat exchange pipe of the indoor heat exchanger (11), the refrigerant heat exchange pipe is controlled to be connected in series in the second pipe, and the water pump (23) is controlled to operate.

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