Heat pump system and control method, device and computer readable storage medium thereof

Abstract

Embodiments of the present application provide a heat pump system, a control method and device thereof, and a computer readable storage medium. The heat pump system comprises a plurality of fixed-frequency heat pump modules and a water-side heat exchanger. The fixed-frequency heat pump module comprises a fixed-frequency compressor, a wind-side heat exchanger and an outdoor fan. The outdoor fan and the wind-side heat exchanger are correspondingly arranged. The water-side heat exchanger is provided with a cold carrier flow channel and a plurality of refrigerant flow channels. The cold carrier flow channel and the refrigerant flow channels, and any two refrigerant flow channels are arranged at intervals. Each refrigerant flow channel is connected with a fixed-frequency heat pump module. The heat pump system control method comprises determining an absolute value of a temperature difference between an inlet water temperature and an outlet water temperature of the cold carrier flow channel; and adjusting the number of the opened fixed-frequency compressors and outdoor fans according to the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the cold carrier flow channel.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of heat pump, in particular to a heat pump system, a control method and device thereof, and a computer readable storage medium. BACKGROUND

[0002] The heat pump system can provide cold energy from the refrigerant side to the chilled water side, and then circulate the chilled water to release the absorbed cold energy to the indoor to meet the indoor heating demand, or release the chilled water to provide hot and cold water. In the related art, some heat pump systems use a fixed frequency module with lower cost. However, the fixed frequency module cannot adjust the operating frequency according to the actual cold energy demand, and the energy saving effect is poor. SUMMARY

[0003] The embodiments of the present application provide a heat pump system, a control method and device thereof, and a computer readable storage medium, which can adjust the operating state of the heat pump system according to the actual cold energy demand, so that the actual refrigeration / heating capacity of the heat pump system matches the actual cold energy demand, and a better energy saving effect is achieved.

[0004] In a first aspect, the embodiments of the present application provide a heat pump system control method, the heat pump system comprising a plurality of fixed frequency heat pump modules and a water side heat exchanger, the fixed frequency heat pump module comprising a fixed frequency compressor, a wind side heat exchanger and an outdoor fan, the outdoor fan and the wind side heat exchanger being correspondingly arranged; the water side heat exchanger is provided with a chilled water flow channel and a plurality of refrigerant flow channels, the chilled water flow channel and the refrigerant flow channels, and any two refrigerant flow channels are arranged at intervals, each refrigerant flow channel is connected with a fixed frequency heat pump module, the heat pump system control method comprising: determining the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the chilled water flow channel; adjusting the number of the started fixed frequency compressors and outdoor fans according to the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the chilled water flow channel.

[0005] In some embodiments, adjusting the number of the started fixed frequency compressors and outdoor fans according to the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the chilled water flow channel comprises: determining the temperature difference interval in which the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the chilled water flow channel is located; adjusting the number of the started fixed frequency compressors and outdoor fans according to the temperature difference interval.

[0006] In some embodiments, the heat pump system comprises two fixed-frequency heat pump modules; and the number of the fixed-frequency compressors and the outdoor fans that are turned on is adjusted according to the temperature difference interval, including: in response to determining that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the cold carrier flow channel is located in a first temperature difference interval, controlling the fixed-frequency compressors and the outdoor fans of the two fixed-frequency heat pump modules to remain in an open state; in response to determining that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the cold carrier flow channel is located in a second temperature difference interval, turning off the outdoor fan of one of the fixed-frequency heat pump modules; in response to determining that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the cold carrier flow channel is located in a third temperature difference interval, turning off the fixed-frequency compressor of one of the fixed-frequency heat pump modules; in response to determining that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the cold carrier flow channel is located in a fourth temperature difference interval, turning off the fixed-frequency compressor and the outdoor fan of one of the fixed-frequency heat pump modules; the first temperature difference interval is a temperature difference interval less than or equal to a first temperature difference threshold, the second temperature difference interval is a temperature difference interval greater than the first temperature difference threshold and less than or equal to a second temperature difference threshold, the third temperature difference interval is a temperature difference interval greater than the second temperature difference threshold and less than or equal to a third temperature difference threshold, and the fourth temperature difference interval is a temperature difference interval greater than the third temperature difference threshold.

[0007] In some embodiments, the heat pump system comprises two fixed-frequency heat pump modules; and the number of the fixed-frequency compressors and the outdoor fans that are turned on is adjusted according to the temperature difference interval, including: in response to determining that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the cold carrier flow channel is located in a first temperature difference interval, controlling the fixed-frequency compressors and the outdoor fans of the two fixed-frequency heat pump modules to remain in an open state; in response to determining that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the cold carrier flow channel is located in a second temperature difference interval, turning off the outdoor fan of one of the fixed-frequency heat pump modules; in response to determining that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the cold carrier flow channel is located in a third temperature difference interval, turning off the fixed-frequency compressor of one of the fixed-frequency heat pump modules; in response to determining that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the cold carrier flow channel is located in a fourth temperature difference interval, turning off the fixed-frequency compressor and the outdoor fan of one of the fixed-frequency heat pump modules; the first temperature difference interval is a temperature difference interval less than or equal to a first temperature difference threshold, the second temperature difference interval is a temperature difference interval greater than the first temperature difference threshold and less than or equal to a second temperature difference threshold, the third temperature difference interval is a temperature difference interval greater than the second temperature difference threshold and less than or equal to a third temperature difference threshold, and the fourth temperature difference interval is a temperature difference interval greater than the third temperature difference threshold.

[0008] In some embodiments, the fixed-frequency heat pump module further comprises a gas-liquid separator, a high-pressure switch and a low-pressure switch, the gas-liquid separator is connected to a refrigerant flow channel of the water-side heat exchanger and a suction port of the compressor, the low-pressure switch is arranged on a connecting pipeline between the gas-liquid separator and the suction port, and the high-pressure switch is connected to a discharge port of the compressor; the heat pump system control method comprises: in response to an exhaust pressure of the gas-liquid separator being less than a first pressure threshold, the low-pressure switch is turned off; in response to the exhaust pressure of the gas-liquid separator being greater than or equal to the first pressure threshold, the low-pressure switch is turned on; in response to a discharge pressure of the compressor being greater than a second pressure threshold, the high-pressure switch is turned off; in response to the discharge pressure of the compressor being less than or equal to the second pressure threshold, the high-pressure switch is turned on; and the first pressure threshold is less than the second pressure threshold.

[0009] In a second aspect, the embodiments of the present application provide a heat pump system control device, comprising: a temperature difference calculation module configured to determine an absolute value of a temperature difference between an inlet water temperature and an outlet water temperature of the secondary refrigerant flow channel; and a switch control module configured to adjust the number of turned-on fixed-frequency compressors and outdoor fans according to the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the secondary refrigerant flow channel.

[0010] In a third aspect, the embodiments of the present application provide a heat pump system, comprising: a plurality of fixed-frequency heat pump modules, each comprising a fixed-frequency compressor, a wind-side heat exchanger and an outdoor fan, wherein the outdoor fan and the wind-side heat exchanger are correspondingly arranged; a water-side heat exchanger provided with a secondary refrigerant flow channel and a plurality of refrigerant flow channels, wherein the secondary refrigerant flow channel and the refrigerant flow channels, and any two of the refrigerant flow channels are arranged at intervals, and each of the refrigerant flow channels is connected to a fixed-frequency heat pump module; a memory storing a computer program; and a processor, wherein the computer program is executed by the processor to implement the heat pump system control method according to any one of the above embodiments.

[0011] In some embodiments, the fixed-frequency heat pump module further comprises a reversing valve, and the reversing valve is connected to the fixed-frequency compressor, the wind-side heat exchanger and the refrigerant flow channel, respectively.

[0012] In some embodiments, the fixed-frequency heat pump module further comprises a gas-liquid separator, a high-pressure switch and a low-pressure switch, the gas-liquid separator is connected to a refrigerant flow channel of the water-side heat exchanger and a suction port of the compressor, the low-pressure switch is arranged on a connecting pipeline between the gas-liquid separator and the suction port, and the high-pressure switch is arranged on a connecting pipeline between the discharge port of the compressor and the reversing valve.

[0013] In a fourth aspect, the embodiments of the present application provide a computer readable storage medium, which stores a computer program. The computer program is loaded by a processor to execute the steps of the heat pump system control method described above.

[0014] The heat pump system control method provided by the embodiments of the present application determines the matching degree between the actual refrigeration / heating capacity of the heat pump system and the actual cooling capacity demand according to the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the cold carrier flow channel, and then adjusts the number of the started fixed-frequency compressors and outdoor fans according to the matching degree, so that the actual refrigeration / heating capacity of the heat pump system and the actual cooling capacity demand are matched, thereby reducing the operation power consumption of the heat pump system and improving the operation energy efficiency of the heat pump system, and achieving a better energy saving effect. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort on the basis of these drawings.

[0016] Figure 1 is a flow chart of the heat pump system control method provided by some embodiments of the present application;

[0017] Figure 2 is a partial flow chart of the heat pump system control method provided by some embodiments of the present application;

[0018] Figure 3 is another partial flow chart of the heat pump system control method provided by some embodiments of the present application;

[0019] Figure 4 is still another partial flow chart of the heat pump system control method provided by some embodiments of the present application;

[0020] Figure 5 is still another partial flow chart of the heat pump system control method provided by some embodiments of the present application;

[0021] Figure 6 is a structural diagram of the heat pump system provided by some embodiments of the present application.

[0022] Main element symbol explanation:

[0023] 1-heat pump system, 10-fixed-frequency heat pump module, 11-fixed-frequency compressor, 12-air side heat exchanger, 13-outdoor fan, 14-reversing valve, 15-gas-liquid separator, 16-high pressure switch, 17-low pressure switch, 20-water side heat exchanger. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present application will be clearly and completely described in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work belong to the protection scope of the present application.

[0025] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element indicated must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features limited by "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise specifically limited.

[0026] "A and / or B" includes the following three combinations: only A, only B, and a combination of A and B.

[0027] The use of "adapted for" or "configured for" in the present application means open and inclusive language that does not exclude devices adapted for or configured for performing additional tasks or steps. In addition, the use of "based on" means open and inclusive, because the process, step, calculation or other action "based on" one or more stated conditions or values can be based on additional conditions or values beyond those stated in practice.

[0028] In the present application, the word "exemplary" is used to mean "serving as an example, instance, or illustration." Any implementation described as "exemplary" in the present application is not necessarily to be construed as preferred or advantageous over other implementations. The following description is presented to enable any person skilled in the art to make and use the present application. In the following description, for the purposes of explanation, numerous details are set forth in order to provide a thorough understanding. It should be apparent to those skilled in the art that the present application can be practiced without the use of these specific details. In other instances, well-known structures and processes are not described in detail in order to avoid obscuring the description of the present application. Thus, the present application is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein.

[0029] As Figure 1 shown in the first aspect, the embodiments of the present application provide a heat pump system control method, which comprises S10-S20. The heat pump system control method can adjust the operating state of the heat pump system 1 according to the actual cooling capacity demand, so that the actual refrigeration / heating capacity of the heat pump system 1 matches the actual cooling capacity demand, and a better energy-saving effect is achieved.

[0030] As Figure 6 shown, the heat pump system 1 comprises a plurality of fixed-frequency heat pump modules 10 and a water-side heat exchanger 20. The fixed-frequency heat pump module 10 comprises a fixed-frequency compressor 11, an air-side heat exchanger 12, and an outdoor fan 13, and the outdoor fan 13 and the air-side heat exchanger 12 are correspondingly arranged. The water-side heat exchanger 20 is provided with a load carrier flow channel and a plurality of refrigerant flow channels, and the load carrier flow channel and the refrigerant flow channels are arranged at intervals, and each refrigerant flow channel is connected to a fixed-frequency heat pump module 10, so that each refrigerant flow channel and the fixed-frequency compressor 11 and the air-side heat exchanger 12 in the fixed-frequency heat pump module 10 are connected to form a refrigerant circulation loop. The refrigerant circulation loop circulates the refrigerant, and the load carrier can flow through the load carrier flow channel; at the water-side heat exchanger 20, the load carrier in the load carrier flow channel and the refrigerant in the refrigerant flow channel can exchange heat, so that the cooling capacity of the refrigerant circulation loop is transferred to the load carrier.

[0031] S10: Determine the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the load carrier flow channel.

[0032] Here, the load carrier flow channel has an inlet water end and an outlet water end arranged on the surface of the water-side heat exchanger 20, and the inlet water temperature and the outlet water temperature of the load carrier flow channel can be measured by temperature sensors arranged at the inlet water end and the outlet water end, respectively. After obtaining the inlet water temperature and the outlet water temperature of the load carrier flow channel, the temperature difference between the inlet water temperature and the outlet water temperature of the load carrier flow channel and the absolute value of the temperature difference can be determined, so as to obtain the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the load carrier flow channel.

[0033] S20: According to the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the load carrier flow channel, adjust the number of started fixed-frequency compressors 11 and outdoor fans 13.

[0034] The degree of matching between the actual cooling / heating capacity and the actual cooling capacity demand of the heat pump system 1 can be determined based on the absolute value of the temperature difference between the inlet and outlet water temperatures of the refrigerant channel. For example, when the absolute value of the temperature difference between the inlet and outlet water temperatures of the refrigerant channel is large, it indicates that the actual cooling / heating capacity of the heat pump system 1 is large, possibly exceeding the actual cooling capacity demand. This indicates poor energy efficiency and potential energy waste, necessitating a reduction in the number of fixed-frequency compressors 11 and / or outdoor fans 13 that are activated. Conversely, when the absolute value of the temperature difference between the inlet and outlet water temperatures of the refrigerant channel is small, it indicates that the actual cooling / heating capacity of the heat pump system 1 is small, possibly less than the actual cooling capacity demand. This indicates that the actual cooling / heating capacity of the heat pump system 1 cannot meet the actual cooling capacity demand, requiring an increase in the number of fixed-frequency compressors 11 and outdoor fans 13 that are activated.

[0035] Furthermore, the number of fixed-frequency compressors 11 and outdoor fans 13 that are turned on can be adjusted according to the matching degree. For example, when the number of fixed-frequency compressors 11 and outdoor fans 13 that need to be turned on is less than the actual number of fixed-frequency compressors 11 and outdoor fans 13 that are turned on, the missing number of fixed-frequency compressors 11 and / or outdoor fans 13 can be controlled to turn on; when the number of fixed-frequency compressors 11 and outdoor fans 13 that need to be turned on is greater than the actual number of fixed-frequency compressors 11 and outdoor fans 13 that are turned on, the excess number of fixed-frequency compressors 11 and / or outdoor fans 13 can be turned off; when the number of fixed-frequency compressors 11 and outdoor fans 13 that need to be turned on is equal to the actual number of fixed-frequency compressors 11 and outdoor fans 13 that are turned on, the on / off adjustment of fixed-frequency compressors 11 and outdoor fans 13 is not required. In this way, the actual cooling / heating capacity of the heat pump system 1 can be matched with the actual cooling demand, thereby reducing the operating power consumption of the heat pump system 1 and improving the operating energy efficiency of the heat pump system 1, achieving better energy-saving effect.

[0036] like Figure 2 As shown, in some embodiments, S20 may include S21 to S22.

[0037] S21: Determine the temperature difference range in which the absolute value of the temperature difference between the inlet and outlet water temperatures of the refrigerant flow channel lies.

[0038] Here, several continuously distributed temperature difference intervals can be pre-set in the controller of the heat pump system 1, and a corresponding start-up quantity adjustment strategy can be set for each temperature difference interval. The number of temperature difference intervals and the length of each temperature difference interval can be determined according to actual needs, and this embodiment does not limit this. Generally speaking, if there are more temperature difference intervals, there will be more start-up quantity adjustment strategies, the matching degree between each start-up quantity adjustment strategy and the temperature difference interval will be higher, and the grading accuracy of the start-up quantity adjustment strategy will be higher. Similarly, if the length of each temperature difference interval is shorter, the temperature range corresponding to each start-up quantity adjustment strategy will be smaller, the matching degree between each start-up quantity adjustment strategy and the temperature difference interval will be higher, and the grading accuracy of the start-up quantity adjustment strategy will be higher. The start-up quantity adjustment strategy may include the number of fixed-frequency compressors 11 and the number of outdoor fans 13 that need to be turned on.

[0039] S22: Adjust the number of fixed-frequency compressors 11 and outdoor fans 13 that are turned on according to the temperature difference range.

[0040] After determining the temperature difference range where the absolute value of the temperature difference between the inlet and outlet water temperatures of the refrigerant flow channel lies, the corresponding start-up quantity adjustment strategy can be determined, thereby determining the number of fixed-frequency compressors 11 and outdoor fans 13 to be turned on, and making corresponding adjustment actions.

[0041] In some examples, the heat pump system 1 may include two fixed-frequency heat pump modules 10. For example... Figure 3 As shown, S22 may include S221 to S224. Here, four continuously distributed temperature difference intervals can be pre-set in the controller of the heat pump system 1, namely, a first temperature difference interval, a second temperature difference interval, a third temperature difference interval, and a fourth temperature difference interval. The first temperature difference interval is the temperature difference interval less than or equal to a first temperature difference threshold, the second temperature difference interval is the temperature difference interval greater than the first temperature difference threshold and less than or equal to the second temperature difference threshold, the third temperature difference interval is the temperature difference interval greater than the second temperature difference threshold and less than or equal to the third temperature difference threshold, and the fourth temperature difference interval is the temperature difference interval greater than the third temperature difference threshold.

[0042] S221: In response to determining that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the refrigerant flow channel is within the first temperature difference range, the fixed-frequency compressor 11 and the outdoor fan 13 of the two fixed-frequency heat pump modules 10 are controlled to remain on.

[0043] When the absolute value of the temperature difference between the inlet and outlet water temperatures of the refrigerant flow channel is within the first temperature difference range, that is, when the absolute value of the temperature difference is less than or equal to the first temperature difference threshold, it indicates that the actual cooling demand is high. The fixed-frequency compressors 11 and outdoor fans 13 of the two fixed-frequency heat pump modules 10 can be kept on to make the actual cooling / heating capacity of the heat pump system 1 match the actual cooling demand.

[0044] S222: In response to determining that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the refrigerant flow channel is located in the second temperature difference interval, turn off the outdoor fan 13 of one of the fixed-frequency heat pump modules 10.

[0045] When it is determined that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the refrigerant flow channel is located in the second temperature difference interval, i.e., the absolute value of the temperature difference is greater than the first temperature difference threshold and less than or equal to the second temperature difference threshold, it indicates that the actual refrigeration / heating capacity of the heat pump system 1 is higher than the actual cooling capacity demand, and the exceeding degree is small. At this time, the fixed-frequency compressor 11 and the outdoor fan 13 of one of the fixed-frequency heat pump modules 10 can be controlled to remain on, and the outdoor fan 13 of the other fixed-frequency heat pump module 10 can be controlled to remain on, but the fixed-frequency compressor 11 is turned off. By controlling the outdoor fan 13 of one of the fixed-frequency heat pump modules 10 to be turned off, the number of outdoor fans 13 that remain on can be reduced, so that the actual refrigeration / heating capacity of the heat pump system 1 is reduced by a small amplitude to the vicinity of the actual cooling capacity demand, the operating power consumption of the heat pump system 1 is reduced to a certain extent, and a better energy-saving effect is achieved.

[0046] S223: In response to determining that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the refrigerant flow channel is located in the third temperature difference interval, turn off the fixed-frequency compressor 11 of one of the fixed-frequency heat pump modules 10.

[0047] When it is determined that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the refrigerant flow channel is located in the third temperature difference interval, i.e., the absolute value of the temperature difference is greater than the second temperature difference threshold and less than or equal to the third temperature difference threshold, it indicates that the actual refrigeration / heating capacity of the heat pump system 1 is higher than the actual cooling capacity demand, and the exceeding degree is moderate. At this time, the fixed-frequency compressor 11 and the outdoor fan 13 of one of the fixed-frequency heat pump modules 10 can be controlled to remain on, and the outdoor fan 13 of the other fixed-frequency heat pump module 10 can be controlled to remain on, but the fixed-frequency compressor 11 is turned off. By controlling the fixed-frequency compressor 11 of one of the fixed-frequency heat pump modules 10 to be turned off, the number of outdoor compressors that remain on can be reduced, so that the actual refrigeration / heating capacity of the heat pump system 1 is reduced by a moderate amplitude to the vicinity of the actual cooling capacity demand, the operating power consumption of the heat pump system 1 is reduced to a moderate extent, and a better energy-saving effect is achieved.

[0048] S224: In response to determining that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the refrigerant flow channel is located in the fourth temperature difference interval, turn off the fixed-frequency compressor 11 and the outdoor fan 13 of one of the fixed-frequency heat pump modules 10.

[0049] When it is determined that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the secondary refrigerant flow channel is located in the fourth temperature difference interval, i.e., the absolute value of the temperature difference is greater than the third temperature difference threshold, it indicates that the actual refrigeration / heating capacity of the heat pump system 1 is higher than the actual cooling capacity demand, and the exceeding degree is greater. At this time, the fixed-frequency compressor 11 and the outdoor fan 13 of one of the fixed-frequency heat pump modules 10 can be controlled to remain open, and the fixed-frequency compressor 11 and the outdoor fan 13 of the other fixed-frequency heat pump module 10 are closed. By controlling the fixed-frequency compressor 11 and the outdoor fan 13 of one of the fixed-frequency heat pump modules 10 to remain closed, the number of outdoor compressors that remain open can be reduced, so that the actual refrigeration / heating capacity of the heat pump system 1 is greatly reduced to the vicinity of the actual cooling capacity demand, the operating power consumption of the heat pump system 1 is greatly reduced, and a better energy-saving effect is achieved.

[0050] In other examples, the heat pump system 1 can include two fixed-frequency heat pump modules 10. As shown in FIG. 2, S22 can include S225-S229. Here, the fifth temperature difference interval is a temperature difference interval less than or equal to the fifth temperature difference threshold, the sixth temperature difference interval is a temperature difference interval greater than the fifth temperature difference threshold and less than or equal to the sixth temperature difference threshold, the seventh temperature difference interval is a temperature difference interval greater than the sixth temperature difference threshold and less than or equal to the seventh temperature difference threshold, the eighth temperature difference interval is a temperature difference interval greater than the seventh temperature difference threshold and less than or equal to the eighth temperature difference threshold, and the ninth temperature difference interval is a temperature difference interval greater than the eighth temperature difference threshold. Figure 4

[0051] S225: In response to determining that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the secondary refrigerant flow channel is located in the fifth temperature difference interval, the fixed-frequency compressors 11 and the outdoor fans 13 of the two fixed-frequency heat pump modules 10 are controlled to remain in the open state.

[0052] When it is determined that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the secondary refrigerant flow channel is located in the fifth temperature difference interval, i.e., the absolute value of the temperature difference is less than or equal to the fifth temperature difference threshold, it indicates that the actual cooling capacity demand is high, and the fixed-frequency compressors 11 and the outdoor fans 13 of the two fixed-frequency heat pump modules 10 can be controlled to remain in the open state, so that the actual refrigeration / heating capacity of the heat pump system 1 is more matched with the actual cooling capacity demand.

[0053] S226: In response to determining that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the secondary refrigerant flow channel is located in the sixth temperature difference interval, the outdoor fan 13 of one of the fixed-frequency heat pump modules 10 is closed.

[0054] ​When it is determined that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the secondary refrigerant flow channel is located in the sixth temperature difference interval, i.e., the absolute value of the temperature difference is greater than the fifth temperature difference threshold and less than or equal to the sixth temperature difference threshold, it indicates that the actual refrigeration / heating capacity of the heat pump system 1 is higher than the actual cooling capacity demand, and the exceeding degree is small. At this time, the fixed-frequency compressor 11 and the outdoor fan 13 of one of the fixed-frequency heat pump modules 10 can be controlled to be kept on, and the outdoor fan 13 of the other fixed-frequency heat pump module 10 is kept on, but the fixed-frequency compressor 11 is turned off. By controlling the outdoor fan 13 of one of the fixed-frequency heat pump modules 10 to be turned off, the number of outdoor fans 13 kept on can be reduced, so that the actual refrigeration / heating capacity of the heat pump system 1 is reduced by a small amplitude to the vicinity of the actual cooling capacity demand, the operating power consumption of the heat pump system 1 is reduced to a certain extent, and a better energy-saving effect is achieved.

[0055] S227: In response to determining that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the secondary refrigerant flow channel is located in the seventh temperature difference interval, the fixed-frequency compressor 11 of one of the fixed-frequency heat pump modules 10 is turned off.

[0056] When it is determined that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the secondary refrigerant flow channel is located in the seventh temperature difference interval, i.e., the absolute value of the temperature difference is greater than the sixth temperature difference threshold and less than or equal to the seventh temperature difference threshold, it indicates that the actual refrigeration / heating capacity of the heat pump system 1 is higher than the actual cooling capacity demand, and the exceeding degree is moderate. At this time, the fixed-frequency compressor 11 and the outdoor fan 13 of one of the fixed-frequency heat pump modules 10 can be controlled to be kept on, and the outdoor fan 13 of the other fixed-frequency heat pump module 10 is kept on, but the fixed-frequency compressor 11 is turned off. By controlling the fixed-frequency compressor 11 of one of the fixed-frequency heat pump modules 10 to be turned off, the number of outdoor compressors kept on can be reduced, so that the actual refrigeration / heating capacity of the heat pump system 1 is reduced by a moderate amplitude to the vicinity of the actual cooling capacity demand, the operating power consumption of the heat pump system 1 is reduced to a moderate degree, and a better energy-saving effect is achieved.

[0057] S228: In response to determining that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the secondary refrigerant flow channel is located in the eighth temperature difference interval, the fixed-frequency compressor 11 of one of the fixed-frequency heat pump modules 10 and the outdoor fan 13 of the other fixed-frequency heat pump module 10 are turned off.

[0058] When the absolute value of the temperature difference between the inlet and outlet water temperatures of the refrigerant channel is determined to be within the eighth temperature difference range (i.e., the absolute value of the temperature difference is greater than the seventh temperature difference threshold but less than or equal to the eighth temperature difference threshold), it indicates that the actual cooling / heating capacity of the heat pump system 1 is higher than the actual cooling demand, and the excess is significant. In this case, the fixed-frequency compressor 11 of one fixed-frequency heat pump module 10 can be shut down while the outdoor fan 13 remains on, while the outdoor fan 13 of the other fixed-frequency heat pump module 10 remains on while the fixed-frequency compressor 11 is shut down. By shutting down the fixed-frequency compressor 11 of one fixed-frequency heat pump module 10 and the outdoor fan 13 of the other fixed-frequency heat pump module 10, the number of outdoor compressors that remain on can be reduced, causing the actual cooling / heating capacity of the heat pump system 1 to drop significantly to near the actual cooling demand, thereby greatly reducing the operating power consumption of the heat pump system 1 and achieving better energy-saving effects.

[0059] S229: In response to determining that the absolute value of the temperature difference between the inlet and outlet water temperatures of the refrigerant flow channel is within the ninth temperature difference range, shut down the fixed-frequency compressor 11 and outdoor fan 13 of one of the fixed-frequency heat pump modules 10.

[0060] When the absolute value of the temperature difference between the inlet and outlet water temperatures of the refrigerant channel is determined to be within the ninth temperature difference range, i.e., the absolute value of the temperature difference is greater than the eighth temperature difference threshold, it indicates that the actual cooling / heating capacity of the heat pump system 1 is higher than the actual cooling demand, and the excess is greater. In this case, the fixed-frequency compressor 11 and outdoor fan 13 of one of the fixed-frequency heat pump modules 10 can be kept on, while the fixed-frequency compressor 11 and outdoor fan 13 of the other fixed-frequency heat pump module 10 can be turned off. By keeping both the fixed-frequency compressor 11 and outdoor fan 13 of one of the fixed-frequency heat pump modules 10 off, the number of outdoor compressors that remain on can be reduced, allowing the actual cooling / heating capacity of the heat pump system 1 to drop more significantly to near the actual cooling demand, further reducing the operating power consumption of the heat pump system 1, and achieving better energy-saving effects.

[0061] Here, the values ​​of the first temperature difference threshold and the fifth temperature difference threshold can be the same or different, the values ​​of the second temperature difference threshold and the sixth temperature difference threshold can be the same or different, and the values ​​of the third temperature difference threshold and the seventh temperature difference threshold can be the same or different. This application embodiment does not limit this.

[0062] like Figure 6 As shown, in some embodiments, the fixed-frequency heat pump module 10 may further include a gas-liquid separator 15, a high-pressure switch 16, and a low-pressure switch 17. The gas-liquid separator 15 is connected to the refrigerant flow channel of the water-side heat exchanger 20 and the suction port of the compressor. The low-pressure switch 17 is disposed on the connecting pipe between the gas-liquid separator 15 and the suction port. The high-pressure switch 16 is connected to the discharge port of the compressor. Figure 5As shown, the heat pump system control method may include S31 to S34.

[0063] S31: In response to the exhaust pressure of the gas-liquid separator 15 being less than the first pressure threshold, the low-pressure switch 17 is turned off.

[0064] S32: In response to the exhaust pressure of the gas-liquid separator 15 being greater than or equal to the first pressure threshold, the low-pressure switch 17 is turned on.

[0065] S33: In response to the compressor's discharge pressure exceeding the second pressure threshold, the high-pressure switch 16 is turned off. Here, the first pressure threshold is less than the second pressure threshold.

[0066] S34: In response to the compressor's discharge pressure being less than or equal to the second pressure threshold, high-pressure switch 16 is turned on.

[0067] By setting S31 to S34, low-pressure protection and high-pressure protection can be provided for the compressor, thereby improving the safe operation performance of the compressor.

[0068] Secondly, embodiments of this application provide a heat pump system control device, which includes: a temperature difference calculation module configured to determine the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the refrigerant channel; and a switch control module configured to adjust the number of the fixed-frequency compressor 11 and the outdoor fan 13 that are turned on based on the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the refrigerant channel.

[0069] like Figure 6 As shown, in a third aspect, embodiments of this application provide a heat pump system 1, which includes multiple fixed-frequency heat pump modules 10, a water-side heat exchanger 20, a processor, and a memory. Each fixed-frequency heat pump module 10 includes a fixed-frequency compressor 11, an air-side heat exchanger 12, and an outdoor fan 13, with the outdoor fan 13 and the air-side heat exchanger 12 correspondingly arranged. The water-side heat exchanger 20 has a refrigerant flow channel and multiple refrigerant flow channels, spaced apart from each other and between any two refrigerant flow channels. Each refrigerant flow channel is connected to a fixed-frequency heat pump module 10. The memory stores a computer program, which, when executed by the processor, implements the heat pump system control method provided in any of the above embodiments.

[0070] The processor is connected to the memory and can perform various actions and processes according to programs stored in the memory. Specifically, the processor can be an integrated circuit chip with processing capability. The processor can be a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, and can implement or execute the various methods, steps and logical block diagrams disclosed in the embodiments of the present application. The general purpose processor can be a microprocessor or the processor can also be any conventional processor, etc., which can be of X86 architecture or ARM architecture.

[0071] The memory can be a volatile memory or a non-volatile memory, or can include both volatile and non-volatile memory. The non-volatile memory can be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM) or a flash memory. The volatile memory can be a random access memory (RAM) used as an external cache. By way of example, but not limitation, many forms of RAM can be used, such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link dynamic random access memory (SLDRAM) and direct memory bus random access memory (DRRAM). It should be noted that the memory of the methods described herein is intended to include, but not be limited to, these and any other suitable types of memory.

[0072] In some embodiments, the fixed frequency heat pump module 10 can further include a reversing valve 14 connected to the fixed frequency compressor 11, the air-side heat exchanger 12 and the refrigerant flow path, respectively. By reversing through the reversing valve 14, the fixed frequency heat pump module 10 can be switched between the cooling mode and the heating mode to realize the cooling and heating function.

[0073] In some embodiments, the fixed frequency heat pump module 10 can further include a gas-liquid separator 15, a high-pressure switch 16 and a low-pressure switch 17. The gas-liquid separator 15 is connected to the refrigerant flow path of the water-side heat exchanger 20 and the suction port of the compressor, the low-pressure switch 17 is arranged on the connecting pipeline between the gas-liquid separator 15 and the suction port, and the high-pressure switch 16 is arranged on the connecting pipeline between the exhaust port of the compressor and the reversing valve 14.

[0074] In a fourth aspect, the embodiments of the present application provide a computer readable storage medium, which stores a computer program. The computer program is loaded by a processor to execute the steps in the control method of any one of the above embodiments.

[0075] By way of example, the computer-readable storage media described above can include, but is not limited to, magnetic storage (e.g., one or more magnetic disks, magnetic tapes, or magnetic drums), optical storage (e.g., one or more CD-ROMs, DVDs, or Blu-Ray discs), smart cards, and flash storage, such as EPROM (Erasable Programmable Read-Only Memory), a card, a stick, or a key drive. The various computer-readable storage media described above can represent one or more devices and / or other machine-readable storage media for storing information. The term "machine-readable storage medium" can include, without being limited to, wireless channels and various other media capable of storing, containing, and / or carrying instruction(s) and / or data.

[0076] The above provides a kind of heat pump system and its control method, device, computer readable storage medium provided by the embodiments of the present application, the principle and implementation of the present application are described in this paper by specific example, the above embodiment is only for helping to understand the method and its core idea of the present application;Meanwhile, for the skilled in the art, according to the idea of the present application, there will be changes in specific implementation and application range, as described above, the content of the specification should not be understood as the limitation of the present application.

Claims

1. A heat pump system control method characterized by, The heat pump system comprises a plurality of fixed-frequency heat pump modules and a water-side heat exchanger, the fixed-frequency heat pump module comprises a fixed-frequency compressor, a wind-side heat exchanger and an outdoor fan, the outdoor fan and the wind-side heat exchanger are correspondingly arranged; the water-side heat exchanger is provided with a cold carrier flow channel and a plurality of refrigerant flow channels, the cold carrier flow channel and the refrigerant flow channels and any two refrigerant flow channels are arranged at intervals, each refrigerant flow channel is connected with a fixed-frequency heat pump module, and the heat pump system control method comprises: determining the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the cold carrier flow channel; adjusting the number of opened fixed-frequency compressors and outdoor fans according to the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the cold carrier flow channel.

2. The heat pump system control method according to claim 1, characterized by, According to the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the cold carrier flow channel, the number of opened fixed-frequency compressors and outdoor fans is adjusted, comprising: determining the temperature difference interval in which the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the cold carrier flow channel is located; adjusting the number of opened fixed-frequency compressors and outdoor fans according to the temperature difference interval.

3. The heat pump system control method according to claim 2, characterized by, The heat pump system comprises two fixed-frequency heat pump modules; According to the temperature difference interval, the number of opened fixed-frequency compressors and outdoor fans is adjusted, comprising: in response to determining that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the cold carrier flow channel is located in the first temperature difference interval, controlling the fixed-frequency compressors and outdoor fans of the two fixed-frequency heat pump modules to keep opened state; in response to determining that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the cold carrier flow channel is located in the second temperature difference interval, closing the outdoor fan of one of the fixed-frequency heat pump modules; in response to determining that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the cold carrier flow channel is located in the third temperature difference interval, closing the fixed-frequency compressor of one of the fixed-frequency heat pump modules; in response to determining that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the cold carrier flow channel is located in the fourth temperature difference interval, closing the fixed-frequency compressor and outdoor fan of one of the fixed-frequency heat pump modules; The first temperature difference interval is a temperature difference interval less than or equal to a first temperature difference threshold, the second temperature difference interval is a temperature difference interval greater than the first temperature difference threshold and less than or equal to a second temperature difference threshold, the third temperature difference interval is a temperature difference interval greater than the second temperature difference threshold and less than or equal to a third temperature difference threshold, and the fourth temperature difference interval is a temperature difference interval greater than the third temperature difference threshold.

4. The heat pump system control method according to claim 2, characterized by, The heat pump system comprises two fixed-frequency heat pump modules; According to the temperature difference interval, the number of opened fixed-frequency compressors and outdoor fans is adjusted, comprising: in response to determining that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the cold carrier flow channel is located in the fifth temperature difference interval, controlling the fixed-frequency compressors and outdoor fans of the two fixed-frequency heat pump modules to keep opened state; in response to determining that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the cold carrier flow channel is located in the sixth temperature difference interval, closing the outdoor fan of one of the fixed-frequency heat pump modules; in response to determining that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the secondary refrigerant flow channel is located in a seventh temperature difference interval, turning off the fixed-frequency compressor of one of the fixed-frequency heat pump modules; in response to determining that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the secondary refrigerant flow channel is located in an eighth temperature difference interval, turning off the fixed-frequency compressor of one of the fixed-frequency heat pump modules and the outdoor fan of another fixed-frequency heat pump module; in response to determining that the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the secondary refrigerant flow channel is located in a ninth temperature difference interval, turning off the fixed-frequency compressor and the outdoor fan of one of the fixed-frequency heat pump modules; the fifth temperature difference interval is a temperature difference interval less than or equal to a fifth temperature difference threshold, the sixth temperature difference interval is a temperature difference interval greater than the fifth temperature difference threshold and less than or equal to a sixth temperature difference threshold, the seventh temperature difference interval is a temperature difference interval greater than the sixth temperature difference threshold and less than or equal to a seventh temperature difference threshold, the eighth temperature difference interval is a temperature difference interval greater than the seventh temperature difference threshold and less than or equal to an eighth temperature difference threshold, and the ninth temperature difference interval is a temperature difference interval greater than the eighth temperature difference threshold.

5. The heat pump system control method according to claim 1, characterized by, The fixed-frequency heat pump module further comprises a gas-liquid separator, a high-pressure switch and a low-pressure switch, the gas-liquid separator is connected to the refrigerant flow channel of the water-side heat exchanger and the suction port of the compressor, the low-pressure switch is arranged on the connecting pipeline between the gas-liquid separator and the suction port, and the high-pressure switch is connected to the exhaust port of the compressor. The heat pump system control method comprises: in response to the exhaust pressure of the gas-liquid separator being less than a first pressure threshold, the low-pressure switch is turned off; in response to the exhaust pressure of the gas-liquid separator being greater than or equal to the first pressure threshold, the low-pressure switch is turned on; in response to the exhaust pressure of the compressor being greater than a second pressure threshold, the high-pressure switch is turned off; in response to the exhaust pressure of the compressor being less than or equal to the second pressure threshold, the high-pressure switch is turned on; The first pressure threshold is less than the second pressure threshold.

6. A heat pump system control device characterized by comprising: The heat pump system comprises a plurality of fixed-frequency heat pump modules and a water-side heat exchanger, the fixed-frequency heat pump module comprises a fixed-frequency compressor, a wind-side heat exchanger and an outdoor fan, the outdoor fan and the wind-side heat exchanger are correspondingly arranged; the water-side heat exchanger is provided with a secondary refrigerant flow channel and a plurality of refrigerant flow channels, the secondary refrigerant flow channel and the refrigerant flow channels and any two refrigerant flow channels are arranged at intervals, each refrigerant flow channel is connected to a fixed-frequency heat pump module, and the heat pump system control device comprises: a temperature difference calculation module configured to determine the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the secondary refrigerant flow channel; a switch control module configured to adjust the number of turned-on fixed-frequency compressors and outdoor fans according to the absolute value of the temperature difference between the inlet water temperature and the outlet water temperature of the secondary refrigerant flow channel.

7. A heat pump system, characterized by, It comprises: a plurality of fixed-frequency heat pump modules comprising a fixed-frequency compressor, a wind-side heat exchanger and an outdoor fan, the outdoor fan and the wind-side heat exchanger are correspondingly arranged; The water side heat exchanger is provided with a load refrigerant flow channel and a plurality of refrigerant flow channels, the load refrigerant flow channel and the refrigerant flow channels are arranged at intervals, each refrigerant flow channel is connected with a fixed frequency heat pump module; A memory storing a computer program; A processor, the computer program is executed by the processor to realize the heat pump system control method in any one of claims 1 to 5.

8. The heat pump system of claim 7, wherein, The fixed frequency heat pump module further comprises a reversing valve connected with the fixed frequency compressor, the air side heat exchanger and the refrigerant flow channel.

9. The heat pump system of claim 8, wherein, The fixed frequency heat pump module further comprises a gas-liquid separator, a high pressure switch and a low pressure switch, the gas-liquid separator is connected with the refrigerant flow channel of the water side heat exchanger and the suction port of the compressor, the low pressure switch is arranged on the connecting pipeline between the gas-liquid separator and the suction port, and the high pressure switch is arranged on the connecting pipeline between the exhaust port of the compressor and the reversing valve.

10. A computer-readable storage medium, characterized in that, A computer program is stored thereon, and the computer program is loaded by a processor to execute the steps in the heat pump system control method in any one of claims 1 to 5.

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