Dual-unit triple-supply anti-freezing control method and heat pump

Abstract

The application discloses a kind of tri-generation anti-freezing control method and heat pump of double unit, which comprises the following steps: monitoring heating side waterway temperature T1, hot water side waterway temperature T2 and ambient temperature T3, judging whether the heating side waterway and the hot water side waterway meet the condition of triggering anti-freezing protection, if meet, switching the working mode of the first unit and / or the second unit, so that at least one heat exchanger in the waterway triggering anti-freezing protection enters working state.The control method of the present application can solve the problem of waterway anti-freezing while ensuring uninterrupted use of heating or hot water by users, reducing water temperature fluctuation and reducing the impact on user experience.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of heat pumps, in particular to a dual-unit triple-generation anti-freezing control method and heat pump. BACKGROUND

[0002] In a conventional triple-generation air energy heat pump unit, two tube-in-tube heat exchangers (or plate heat exchangers) and one fin heat exchanger are generally provided. One tube-in-tube heat exchanger is connected with a heating side water circuit, and the other tube-in-tube heat exchanger is connected with a hot water side water circuit. The fin heat exchanger exchanges heat with outdoor air. In a winter heating mode, only one of the two tube-in-tube heat exchangers can be started at the same time, and the water in the stopped tube-in-tube heat exchanger is prone to freezing and ice formation, which may cause the tube-in-tube heat exchanger to expand and crack. Once the heat exchanger is damaged, the water system or the fluorine system may be damaged or leaked, so that the unit cannot work normally. SUMMARY

[0003] The purpose of the embodiment of the present application is to provide a dual-unit triple-generation anti-freezing control method and heat pump, which can solve the above problems existing in the prior art.

[0004] To achieve the above purpose, the following technical scheme is adopted in the present application:

[0005] On the one hand, a dual-unit triple-generation anti-freezing control method is provided, which comprises the steps of: monitoring a heating side water circuit temperature T1, a hot water side water circuit temperature T2 and an environment temperature T3, judging whether the heating side water circuit and the hot water side water circuit meet the conditions for triggering anti-freezing protection, and if so, switching the working mode of a first unit and / or a second unit, so that at least one heat exchanger in the water circuit triggering anti-freezing protection enters a working state.

[0006] Optionally, the temperature of the water circuit triggering anti-freezing protection is continuously monitored, and it is judged whether the conditions for exiting anti-freezing protection are met. If so, the heat supply to the water circuit is stopped.

[0007] Optionally, when T3≤a and T1≤b, the heating side meets the conditions for triggering anti-freezing protection; when T3≤a and T2≤b, the hot water side meets the conditions for triggering anti-freezing protection.

[0008] Optionally, when T1≥c for a duration of t is monitored, the heating side meets the conditions for exiting anti-freezing protection; when T2≥c for a duration of t is monitored, the hot water side meets the conditions for exiting anti-freezing protection.

[0009] Optionally, when the water circuit triggering anti-freezing protection meets the conditions for exiting anti-freezing protection, and the other side water circuit does not meet the conditions for exiting anti-freezing protection or the water temperature has not reached a set value, the unit originally supplying heat to the water circuit exiting anti-freezing protection is switched to supply heat to the other side water circuit.

[0010] Optionally, in the standby mode, when the heating side waterway and the hot water side waterway both trigger the anti-freezing protection, the first unit is started to supply heat for the heating side waterway, and the second unit is started to supply heat for the hot water side waterway; when one side of the heating side waterway and the hot water side waterway meets the anti-freezing protection exit condition, and the other side does not meet the anti-freezing protection exit condition, the first unit and the second unit are switched to supply heat for the waterway which does not exit the anti-freezing protection.

[0011] Optionally, in the hot water mode, when the heating side waterway triggers the anti-freezing protection, the first unit is switched to supply heat for the heating side waterway; when the heating side waterway meets the anti-freezing protection exit condition, and the temperature of the hot water side waterway does not reach the set value, the first unit is switched to supply heat for the hot water side waterway; when the heating side waterway does not meet the anti-freezing protection exit condition, and the temperature of the hot water side waterway reaches the set value, the second unit is switched to supply heat for the heating side waterway.

[0012] Optionally, in the heating mode, when the hot water side waterway triggers the anti-freezing protection, the first unit is switched to supply heat for the hot water side waterway; when the hot water side waterway meets the anti-freezing protection exit condition, and the temperature of the heating side waterway does not reach the set value, the first unit is switched to supply heat for the heating side waterway; when the hot water side waterway does not meet the anti-freezing protection exit condition, and the temperature of the heating side waterway reaches the set value, the second unit is switched to supply heat for the hot water side waterway.

[0013] On the other hand, a dual-unit tri-generation heat pump for executing the above-mentioned control method is provided, comprising a first unit and a second unit, the first unit comprising a first heat exchanger, a second heat exchanger and a third heat exchanger, the second unit comprising a fourth heat exchanger, a fifth heat exchanger and a sixth heat exchanger, the first heat exchanger and the fourth heat exchanger are both connected with a heating side waterway, the second heat exchanger and the fifth heat exchanger are both connected with a hot water side waterway, and the third heat exchanger and the sixth heat exchanger are both finned heat exchangers.

[0014] Optionally, the first unit further comprises a first compressor, a first variable frequency board and a first variable frequency radiator installed on the first variable frequency board, the first variable frequency radiator is connected to one side of the first heat exchanger, the second heat exchanger and the third heat exchanger away from the first compressor, so as to accelerate the heat dissipation of the first variable frequency board by using the liquid refrigerant output by the first heat exchanger, the second heat exchanger or the third heat exchanger; the second unit further comprises a second compressor, a second variable frequency board and a second variable frequency radiator installed on the second variable frequency board, the second variable frequency radiator is connected to one side of the fourth heat exchanger, the fifth heat exchanger and the sixth heat exchanger away from the second compressor, so as to accelerate the heat dissipation of the second variable frequency board by using the liquid refrigerant output by the fourth heat exchanger, the fifth heat exchanger or the sixth heat exchanger.

[0015] The application has the beneficial effects that: the application provides a dual-unit triple supply anti-freezing control method and heat pump, two sets of units are arranged, and each set of unit is connected with a heating side waterway and a hot water side waterway, when it is monitored that there is a risk of freezing ice on a certain side waterway, the two sets of units are independently controlled, one set of unit is switched to the other side waterway without interrupting the provision of heating or hot water, and the problem of freezing ice of the waterway is avoided. BRIEF DESCRIPTION OF DRAWINGS

[0016] The application will be further described in detail below according to the drawings and embodiments.

[0017] Figure 1 The structure principle diagram of the dual-unit triple supply heat pump of the embodiment of the application is shown in the figure.

[0018] Figure 2 The structure principle diagram of the first unit of the embodiment of the application is shown in the figure.

[0019] Figure 3 The enlarged schematic view of the A area in the figure is shown in the figure. Figure 2 The enlarged schematic view of the B area in the figure is shown in the figure.

[0020] Figure 4 The operation principle diagram of the first unit of the embodiment of the application in the refrigeration mode is shown in the figure. Figure 2 The operation principle diagram of the first unit of the embodiment of the application in the heating mode is shown in the figure.

[0021] Figure 5 The operation principle diagram of the first unit of the embodiment of the application in the heating defrosting mode is shown in the figure.

[0022] Figure 6 The operation principle diagram of the first unit of the embodiment of the application in the hot water + refrigeration mode is shown in the figure.

[0023] Figure 7 The operation principle diagram of the first unit of the embodiment of the application in the hot water mode is shown in the figure.

[0024] Figure 8 The operation principle diagram of the first unit of the embodiment of the application in the hot water defrosting mode is shown in the figure.

[0025] Figure 9 The operation principle diagram of the first unit of the embodiment of the application in the hot water mode is shown in the figure.

[0026] Figure 10 The operation principle diagram of the first unit of the embodiment of the application in the hot water defrosting mode is shown in the figure.

[0027] In the figure:

[0028] 100, first unit; 200, second unit; 300, heating side water circuit; 400, hot water side water circuit; 11, first compressor; 12, second compressor; 2, first variable frequency radiator; 21, first variable frequency board; 31, first heat exchanger; 32, second heat exchanger; 33, third heat exchanger; 34, fourth heat exchanger; 35, fifth heat exchanger; 36, sixth heat exchanger; 4, first four-way valve; 41, a interface; 42, b interface; 43, c interface; 44, d interface; 5, second four-way valve; 51, e interface; 52, f interface; 53, g interface; 54, h interface; 6, flow direction adjusting valve group; 61, first three-way; 611, first total interface; 612, first sub-interface; 613, second sub-interface; 62, second three-way; 621, second total interface; 622, third sub-interface; 623, fourth sub-interface; 63, third three-way; 631, third total interface; 632, fifth sub-interface; 633, sixth sub-interface; 64, fourth three-way; 641, fourth total interface; 642, seventh sub-interface; 643, eighth sub-interface; 65, first check valve; 66, second check valve; 67, third check valve; 68, fourth check valve; 7, liquid storage tank; 81, fifth three-way; 82, sixth three-way; 83, fifth check valve; 91, sixth check valve; 92, first throttling valve; 93, seventh check valve; 94, second throttling valve. DETAILED DESCRIPTION

[0029] In order to make the technical problems solved in the present application, the technical solutions adopted and the technical effects achieved more clear, the technical solutions of the embodiments of the present application are described in further detail below. Obviously, the described embodiments are only some of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0030] In the description of the present application, unless otherwise explicitly specified and limited, the terms "connected", "connected", "fixed" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0031] In the present application, unless specifically defined and limited otherwise, "on" or "under" of a first feature with respect to a second feature can include that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, "on", "above" and "over" of a first feature with respect to a second feature includes that the first feature is directly above and obliquely above the second feature, or only indicates that the first feature is higher than the second feature in horizontal height. "Under", "below" and "underneath" of a first feature with respect to a second feature includes that the first feature is directly below and obliquely below the second feature, or only indicates that the first feature is lower than the second feature in horizontal height.

[0032] As shown in Figure 1 The embodiment provides a dual-unit triple supply heat pump, which comprises a first unit 100 and a second unit 200. The first unit 100 comprises a first heat exchanger 31, a second heat exchanger 32 and a third heat exchanger 33. The second unit 200 comprises a fourth heat exchanger 34, a fifth heat exchanger 35 and a sixth heat exchanger 36. The first heat exchanger 31 and the fourth heat exchanger 34 are connected with a heating side water circuit 300. The second heat exchanger 32 and the fifth heat exchanger 35 are connected with a hot water side water circuit 400. The third heat exchanger 33 and the sixth heat exchanger 36 are finned heat exchangers.

[0033] In the dual-unit triple supply heat pump, the refrigerant systems of the first unit 100 and the second unit 200 are independent of each other, but the water circuit systems are shared, that is, the first unit 100 has an independent first compressor 11, and the first compressor 11 drives the refrigerant to circulate between the first heat exchanger 31, the second heat exchanger 32 and the third heat exchanger 33. The second unit 200 has an independent second compressor 12, and the second compressor 12 drives the refrigerant to circulate between the fourth heat exchanger 34, the fifth heat exchanger 35 and the sixth heat exchanger 36. In the shared water circuit system, the first heat exchanger 31 and the fourth heat exchanger 34 are simultaneously connected to the heating side water circuit 300, and the second heat exchanger 32 and the fifth heat exchanger 35 are simultaneously connected to the hot water side water circuit 400, so that the trend of the first unit 100 and the second unit 200 can be freely controlled, and the two units can simultaneously supply heat to the heating side water circuit 300, or simultaneously supply heat to the hot water side water circuit 400, or one supplies heat to the heating side water circuit 300 and the other supplies heat to the hot water side water circuit 400.

[0034] In a conventional triple-combined air energy heat pump unit, two tube-in-tube heat exchangers (or plate heat exchangers) and a finned heat exchanger are generally provided, one tube-in-tube heat exchanger is connected with a heating side water circuit, the other tube-in-tube heat exchanger is connected with a hot water side water circuit, and the finned heat exchanger exchanges heat with outdoor air. In a winter heating mode, only one of the two tube-in-tube heat exchangers can be started at the same time, and the water in the stopped tube-in-tube heat exchanger is prone to freezing, which may cause the tube-in-tube heat exchanger to crack. Once the heat exchanger is damaged, the water system or the fluorine system may be damaged or leaked, so that the unit cannot work normally.

[0035] Since only one water circuit can be heated at the same time in a heat pump system, the conventional triple-combined heat pump can only stop the original heating end and start another heating end to avoid thawing when facing the anti-freezing problem. For example, when a user needs heating, in the case of running a heating mode, when the system monitors that the hot water side water circuit has a freezing risk, it can only pause heating for the heating water circuit and switch to heating for the hot water side water circuit. After the hot water side water circuit is no longer in the anti-freezing alarm state, the heating mode is restarted. That is, the conventional solution needs to interrupt the use of the user end when solving the anti-freezing problem, which causes the water temperature to drop rapidly and affects the user experience.

[0036] In order to solve the anti-freezing problem without affecting the user experience, a triple-combined heat pump with double units based on the present embodiment provides an anti-freezing control method, which includes the steps of monitoring the heating side water circuit temperature T1, the hot water side water circuit temperature T2 and the environment temperature T3, judging whether the heating side water circuit and the hot water side water circuit meet the conditions for triggering the anti-freezing protection, and if so, switching the working mode of the first unit and / or the second unit to make at least one heat exchanger in the water circuit triggering the anti-freezing protection enter the working state.

[0037] Generally, in winter, users have the demand of indoor heating and hot water use. The triple-combined heat pump with double units based on the present embodiment can start the heating mode, the hot water mode and the heating+hot water mode in winter.

[0038] In the standby state, when it is monitored that the heating side water circuit 300 meets the conditions for triggering the anti-freezing protection, the first heat exchanger 31 and / or the fourth heat exchanger 34 can be started to run the heating; when it is monitored that the hot water side water circuit 400 meets the conditions for triggering the anti-freezing protection, the second heat exchanger 32 and / or the fifth heat exchanger 35 can be started to run the heating; when it is monitored that the heating side water circuit 300 and the hot water side water circuit 400 meet the conditions for triggering the anti-freezing protection at the same time, the first heat exchanger 31 or the fourth heat exchanger 34 can be started to heat the heating side water circuit 300, and the second heat exchanger 32 or the fifth heat exchanger 35 can be started to heat the hot water side water circuit 400.

[0039] In the heating mode, when the hot water side waterway 400 meets the condition triggering the anti-freezing protection, the second heat exchanger 32 or the fifth heat exchanger 35 can be started to run the heating, and the heating side waterway 300 keeps one heat exchanger running.

[0040] In the hot water mode, when the heating side waterway 300 meets the condition triggering the anti-freezing protection, the first heat exchanger 31 or the fourth heat exchanger 34 can be started to run the heating, and the hot water side waterway 400 keeps one heat exchanger running.

[0041] In the heating + hot water mode, both sides of the waterway are in a continuous heating state, so there is no anti-freezing protection condition.

[0042] Based on the triple-generation anti-freezing control method of the double units, two sets of units are provided, and each set of units is connected with the heating side waterway 300 and the hot water side waterway 400. When it is monitored that there is a risk of freezing ice on one side of the waterway, the two sets of units are independently controlled, one set of units is switched to the other side of the waterway without interrupting the heating or hot water supply, thereby avoiding the problem of freezing ice on the waterway. Therefore, the control method can solve the problem of waterway anti-freezing while ensuring uninterrupted heating or hot water use for users, reducing water temperature fluctuations and reducing the impact on user experience.

[0043] In an embodiment, when one side of the waterway or both sides of the waterway triggers the anti-freezing protection, the temperature of the waterway triggering the anti-freezing protection is continuously monitored to determine whether the condition for exiting the anti-freezing protection is met. If so, the heating for the waterway is stopped.

[0044] Exiting the anti-freezing protection after heating to a certain temperature can avoid heating the water temperature of the waterway that is not in use to be too high, thereby causing excessive energy waste.

[0045] Regarding the condition triggering the anti-freezing protection, in an embodiment, when T3≤a and T1≤b, the heating side meets the condition triggering the anti-freezing protection; when T3≤a and T2≤b, the hot water side meets the condition triggering the anti-freezing protection.

[0046] Preferably, a=2℃~3℃, b=6℃~8℃.

[0047] Triggering the anti-freezing protection immediately under the above conditions can ensure that the water is heated and warmed before the waterway freezes, thereby avoiding the rapid temperature drop of the environment T3 and the occurrence of ice in the waterway.

[0048] Regarding the condition for exiting the anti-freezing protection, in an embodiment, when T1≥c is monitored for a duration of t, the heating side meets the condition for exiting the anti-freezing protection; when T2≥c is monitored for a duration of t, the hot water side meets the condition for exiting the anti-freezing protection.

[0049] Preferably, c = 13 ~ 16 ℃, t = 3 ~ 6 min.

[0050] Because the higher the heating temperature, the greater the temperature difference between the water temperature and the ambient temperature, and the higher the heat dissipation efficiency, the water temperature is heated to 13 ~ 16 ℃ or more and lasts for 3 ~ 6 min before exiting the anti-freezing protection, avoiding the problem of excessive energy consumption caused by heating the water temperature too high; It can also avoid the problem of frequent start-stop of anti-freezing protection caused by insufficient heating of water temperature.

[0051] In an embodiment, when the water path that triggers the anti-freezing protection meets the condition for exiting the anti-freezing protection, and the other side water path does not meet the condition for exiting the anti-freezing protection or the water temperature has not reached the set value, the unit that originally supplies heat to the water path that exits the anti-freezing protection is switched to supply heat to the other side water path.

[0052] Specifically, when one side exits the anti-freezing protection, and the other side does not meet the anti-freezing protection condition or does not reach the user's set temperature value, the unit that originally supplies heat to the anti-freezing side is automatically switched to the other side, which can speed up the temperature rise of the side.

[0053] In an embodiment, in standby mode, when the heating side water path and the hot water side water path both trigger the anti-freezing protection, start the first unit to supply heat to the heating side water path and the second unit to supply heat to the hot water side water path; When one side of the heating side water path and the hot water side water path meets the anti-freezing protection condition, and the other side does not meet the anti-freezing protection condition, switch the first unit and the second unit to supply heat to the water path that does not exit the anti-freezing protection at the same time.

[0054] After one side water path exits the anti-freezing protection, two units supply heat to the water path that does not exit the anti-freezing protection at the same time, which can quickly contact the anti-freezing protection of the side water path.

[0055] In an embodiment, in hot water mode, when the heating side water path triggers the anti-freezing protection, switch the first unit to supply heat to the heating side water path; When the heating side water path meets the anti-freezing protection condition, and the hot water side water path temperature does not reach the set value, switch the first unit to supply heat to the hot water side water path; When the heating side water path does not meet the anti-freezing protection condition, and the hot water side water path temperature reaches the set value, switch the second unit to supply heat to the heating side water path.

[0056] Specifically, in the hot water mode, the user sets the hot water temperature to a certain value, and when the hot water temperature reaches the set value, the hot water side waterway is suspended from being heated. In the normal hot water mode state, the first unit and the second unit simultaneously heat the hot water side waterway; when the heating side waterway triggers the freeze protection, the first unit or the second unit switches to heat the heating side waterway; when the heating side waterway exits the freeze protection in advance, or the hot water side waterway reaches the set temperature value in advance, the first unit and the second unit simultaneously heat the other side waterway.

[0057] In an embodiment, in the heating mode, when the hot water side waterway triggers the freeze protection, the first unit is switched to heat the hot water side waterway; when the hot water side waterway meets the freeze protection exit condition and the heating side waterway temperature does not reach the set value, the first unit is switched to heat the heating side waterway; when the hot water side waterway does not meet the freeze protection exit condition and the heating side waterway temperature reaches the set value, the second unit is switched to heat the hot water side waterway.

[0058] Specifically, in the heating mode, the user sets the heating temperature to a certain value, and when the heating temperature reaches the set value, the heating side waterway is suspended from being heated. In the normal heating mode state, the first unit and the second unit simultaneously heat the heating side waterway; when the hot water side waterway triggers the freeze protection, the first unit or the second unit switches to heat the hot water side waterway; when the hot water side waterway exits the freeze protection in advance, or the heating side waterway reaches the set temperature value in advance, the first unit and the second unit simultaneously heat the other side waterway.

[0059] The first unit 100 and the second unit 200 of the embodiment are both variable frequency heat pumps. At present, the main cooling measures for variable frequency boards are to place them in a wind cavity or use external fans in an electrical box for forced convection heat exchange, so as to cool the variable frequency board. However, the space required for setting up the fan convection heat exchange is large, and the fan assembly increases the additional power of the unit, resulting in the problems of increased volume of the electrical box and increased power consumption of the unit.

[0060] To overcome the above problems, regarding the dual-unit triple supply heat pump of the present embodiment, in a further scheme, the first unit 100 further comprises a first compressor 11, a first variable frequency board 21, and a first variable frequency radiator 2 installed on the first variable frequency board 21, the first variable frequency radiator 2 being connected to the first heat exchanger 31, the second heat exchanger 32, and the third heat exchanger 33 away from the first compressor 11, so as to accelerate the heat dissipation of the first variable frequency board 21 by using the liquid coolant output by the first heat exchanger 31, the second heat exchanger 32, or the third heat exchanger 33; the second unit 200 further comprises a second compressor 12, a second variable frequency board, and a second variable frequency radiator installed on the second variable frequency board, the second variable frequency radiator being connected to the fourth heat exchanger 34, the fifth heat exchanger 35, and the sixth heat exchanger 36 away from the second compressor 12, so as to accelerate the heat dissipation of the second variable frequency board by using the liquid coolant output by the fourth heat exchanger 34, the fifth heat exchanger 35, or the sixth heat exchanger 36.

[0061] The structure and principle of the second unit 200 are the same as those of the first unit 100, and only the first unit 100 is described below. The second unit 200 can be set in accordance with the first unit 100.

[0062] Specifically, the same as the principle of a conventional air conditioning system, the first unit 100 of the present scheme at least comprises a compressor-condenser-throttle valve-evaporator-compressor connected in sequence. The coolant is condensed to form medium-temperature liquid coolant in the condenser and evaporated to form low-temperature gaseous coolant in the evaporator. The first variable frequency radiator 2 is arranged at the end of the first heat exchanger 31, the second heat exchanger 32, and the third heat exchanger 33 away from the first compressor 11, that is, the first variable frequency radiator 2 is always located at the rear end of the condenser regardless of the flow direction of the coolant in the first unit 100.

[0063] The variable frequency board heat dissipation structure of the embodiment can be used in a heat pump system. In the heat pump system, a first variable frequency heat radiator 2 connected with the first variable frequency board 21 is arranged at the rear end of the condenser. When the unit is running, the refrigerant is condensed in the condenser to form medium-temperature liquid refrigerant. The temperature of the medium-temperature liquid refrigerant is lower than the surface temperature of the first variable frequency board 21, and the temperature difference between them is not large. When the medium-temperature liquid refrigerant flows through the first variable frequency heat radiator 2, it will carry part of the heat on the surface of the first variable frequency board 21, achieving the effect of accelerating the heat dissipation of the first variable frequency board 21. In the scheme, no additional heat dissipation fan is needed for the first variable frequency board 21, and no space is needed for air convection of the heat dissipation fan, avoiding the problem of increasing the volume of the electrical box caused by the convection heat dissipation, and avoiding the problem of increasing the power consumption of the unit caused by the setting of the heat dissipation fan. In addition, the medium-temperature liquid refrigerant is used to dissipate heat for the first variable frequency board 21 in the scheme. Compared with the low-temperature gaseous refrigerant at the rear end of the evaporator, the medium-temperature liquid refrigerant at the rear end of the condenser has a higher temperature, and the temperature difference between it and the first variable frequency board 21 is smaller. The condensation of the first variable frequency heat radiator 2 surface caused by the large temperature difference can be avoided, and the problem of condensation in the electrical box threatening the safety of the circuit can be avoided.

[0064] In an embodiment, referring to Figure 1 Further comprising a liquid storage tank 7, the first heat exchanger 31, the second heat exchanger 32 and the third heat exchanger 33 are away from one side of the first compressor 11.

[0065] The setting of the liquid storage tank 7 can store liquid refrigerant and provide stable and sufficient refrigerant for the heat pump system circuit.

[0066] In an embodiment, referring to Figure 1 and 2 The heat pump system to which the variable frequency board heat dissipation structure of the embodiment is applied comprises a first four-way valve 4 and a second four-way valve 5. The first four-way valve 4 comprises an a interface 41, a b interface 42, a c interface 43 and a d interface 44. The second four-way valve 5 comprises an e interface 51, an f interface 52, a g interface 53 and an h interface 54. The output end of the first compressor 11 is connected to the e interface 51, and the f interface 52 is connected to the a interface 41. The h interface 54 is connected to the input end of the first compressor 11, and the g interface 53 is connected to one end of the second heat exchanger 32. The other end of the second heat exchanger 32 is connected to one end of the liquid storage tank 7 away from the first variable frequency heat radiator 2. The d interface 44 is connected to the input end of the first compressor 11. One end of the first heat exchanger 31 is connected to the b interface 42, and the other end is connected to one end of the liquid storage tank 7 away from the first variable frequency heat radiator 2. One end of the third heat exchanger 33 is connected to the c interface 43, and the other end is connected to the first variable frequency heat radiator 2.

[0067] Based on the above scheme, by switching the conduction direction of the first four-way valve 4 and the second four-way valve 5, the flow direction of the refrigerant in the system can be switched, and the functions of the first heat exchanger 31, the third heat exchanger 33 and the second heat exchanger 32 can be changed to realize different use functions. Specifically, the first heat exchanger 31 can be used to provide cold air or warm air for the indoor, and the second heat exchanger 32 can be used to provide hot water for the indoor, that is, the first unit 100 can realize refrigeration function, heating function, hot water function and hot water + refrigeration function.

[0068] Based on the above heat pump system, in actual use, by switching the conduction direction of the first four-way valve 4, the flow direction of the refrigerant in the system can be switched, and the functions of the first heat exchanger 31 and the third heat exchanger 33 can be changed to realize different use functions. Specifically, the first heat exchanger 31 exchanges heat with indoor air or indoor hot water to realize cold or heating supply for the indoor, and the third heat exchanger 33 exchanges heat with outdoor air, that is, the heat pump system is a two-supply system, which can realize refrigeration function and heating function.

[0069] In the open refrigeration mode, referring to Figure 5 , the e interface 51 and the f interface 52 of the second four-way valve 5 are conducted, the a interface 41 and the c interface 43 of the first four-way valve 4 are conducted, the b interface 42 and the d interface 44 are conducted, and the circulation loop of the refrigerant is: the first compressor 11-the second four-way valve 5-the first four-way valve 4-the third heat exchanger 33-the first variable frequency radiator 2-the throttling valve-the first heat exchanger 31-the first four-way valve 4-the first compressor 11. In this process, the first heat exchanger 31 acts as an evaporator, and the third heat exchanger 33 acts as a condenser. The liquid refrigerant output by the third heat exchanger 33 flows through the first variable frequency radiator 2 to accelerate the heat dissipation of the first variable frequency plate 21, and the first heat exchanger 31 directly or indirectly outputs cold air to the indoor to realize refrigeration.

[0070] In the open heating mode, referring to Figure 6 , the e interface 51 and the f interface 52 of the second four-way valve 5 are conducted, the a interface 41 and the b interface 42 of the first four-way valve 4 are conducted, the c interface 43 and the d interface 44 are conducted, and the circulation loop of the refrigerant is: the first compressor 11-the second four-way valve 5-the first four-way valve 4-the first heat exchanger 31-the first variable frequency radiator 2-the throttling valve-the third heat exchanger 33-the first four-way valve 4-the first compressor 11. In this process, the first heat exchanger 31 acts as a condenser, and the third heat exchanger 33 acts as an evaporator. The liquid refrigerant output by the first heat exchanger 31 flows through the first variable frequency radiator 2 to accelerate the heat dissipation of the first variable frequency plate 21, and the first heat exchanger 31 directly or indirectly outputs warm air to the indoor to realize heating.

[0071] In winter, the ambient temperature is low, and the heating mode is generally opened. The third heat exchanger 33 continuously absorbs heat, and after a long time of operation, frost is easily formed on the surface of the third heat exchanger 33. Therefore, in order to realize defrosting, referring toFigure 7 When frost is found on the third heat exchanger 33, the heating defrosting mode can be activated. Similar to the cooling mode, the e port 51 and f port 52 of the second four-way valve are connected, the a port 41 and c port 43 of the first four-way valve 4 are connected, and the b port 42 and d port 44 are connected. The refrigerant circulation loop is: first compressor 11 - second four-way valve 5 - first four-way valve 4 - third heat exchanger 33 - first variable frequency radiator 2 - throttle valve - first heat exchanger 31 - first four-way valve 4 - first compressor 11. In this process, the first heat exchanger 31 acts as an evaporator, and the third heat exchanger 33 acts as a condenser. The liquid refrigerant output from the third heat exchanger 33 flows through the first variable frequency radiator 2 to accelerate the heat dissipation of the first variable frequency plate 21. The third heat exchanger 33 continuously dissipates heat to the outside to achieve defrosting.

[0072] In one embodiment, an enthalpy-increasing circuit is provided in the heat pump system, compared to Figure 5 and Figure 7 When the cooling mode is activated and the system enters steady-state operation, the enthalpy-increasing circuit is opened to improve cooling performance. When the heating defrost mode is activated, the heating defrost mode is only activated briefly, and the system needs to switch back to heating mode after defrosting is completed. Therefore, heating defrost is a non-steady-state process, and the enthalpy-increasing effect is poor in the non-steady-state state. Therefore, the enthalpy-increasing circuit is closed in the heating defrost mode.

[0073] When the hot water + cooling mode is turned on, refer to Figure 8 The e port 51 and g port 53 of the second four-way valve 5 are connected, and the b port 42 and d port 44 of the first four-way valve 4 are connected. The refrigerant circulation loop is: first compressor 11 - second four-way valve 5 - second heat exchanger 32 - first variable frequency radiator 2 - throttle valve - first heat exchanger 31 - first four-way valve 4 - first compressor 11. In this process, the first heat exchanger 31 acts as an evaporator, and the second heat exchanger 32 acts as a condenser. The liquid refrigerant output by the second heat exchanger 32 flows through the first variable frequency radiator 2 to accelerate the heat dissipation of the first variable frequency plate 21. The first heat exchanger 31 directly or indirectly outputs cold air to the room to achieve refrigeration, and the second heat exchanger 32 provides hot water to the room.

[0074] When the hot water mode is turned on, refer to Figure 9 The e port 51 and g port 53 of the second four-way valve 5 are connected, and the c port 43 and d port 44 of the first four-way valve 4 are connected. The refrigerant circulation loop is: first compressor 11 - second four-way valve 5 - second heat exchanger 32 - first variable frequency radiator 2 - throttle valve - third heat exchanger 33 - first four-way valve 4 - first compressor 11. In this process, the third heat exchanger 33 acts as an evaporator, and the second heat exchanger 32 acts as a condenser. The liquid refrigerant output by the second heat exchanger 32 flows through the first variable frequency radiator 2 to accelerate the heat dissipation of the first variable frequency plate 21. The second heat exchanger 32 provides hot water to the room.

[0075] In winter, the ambient temperature is low, and after the hot water mode is started, the third heat exchanger 33 continuously absorbs heat, and after a long time of operation, frost is likely to form on the surface of the third heat exchanger 33. Therefore, in order to realize defrosting, with reference to Figure 10 When it is found that the third heat exchanger 33 is frosted, the hot water defrosting mode can be started, the e interface 51 and the f interface 52 of the second four-way valve 5 are connected, the g interface 53 and the h interface 54 are connected, the a interface 41 and the c interface 43 of the first four-way valve 4 are connected, and the circulation loop of the refrigerant is: the first compressor 11-the second four-way valve 5-the first four-way valve 4-the third heat exchanger 33-the first variable frequency radiator 2-the throttling valve-the second heat exchanger 32-the second four-way valve 5-the first compressor 11. In this process, the second heat exchanger 32 acts as an evaporator, and the third heat exchanger 33 acts as a condenser. The liquid refrigerant output by the third heat exchanger 33 flows through the first variable frequency radiator 2 to accelerate the heat dissipation of the first variable frequency plate 21, and the third heat exchanger 33 continuously dissipates heat to the outside to realize defrosting.

[0076] As can be seen from the above, in the first unit 100 of the embodiment, in the refrigeration mode, the heating mode, the heating defrosting mode, the hot water + refrigeration mode, the hot water mode and the hot water defrosting mode, the first variable frequency radiator 2 can always be placed at the rear end of the condenser, and the liquid refrigerant is used for heat dissipation.

[0077] In a further embodiment, the first unit 100 further comprises a flow direction adjusting valve group 6, the flow direction adjusting valve group 6 has a first total interface 611, a second total interface 621, a third total interface 631 and a fourth total interface 641, one end of the first heat exchanger 31 away from the b interface 42 is connected to the first total interface 611, one end of the third heat exchanger 33 away from the c interface 43 is connected to the second total interface 621, one end of the liquid storage tank 7 is connected to the third total interface 631, and the other end is connected to one end of the first variable frequency radiator 2, the other end of the first variable frequency radiator 2 is connected to the fourth total interface 641; in the flow direction adjusting valve group 6, the refrigerant always flows out of the flow direction adjusting valve group 6 from the third total interface 631 and flows back to the flow direction adjusting valve group 6 from the fourth total interface 641.

[0078] Specifically, in the embodiment, the role of the flow direction adjusting valve group 6 is to adjust the flow direction of the refrigerant in the liquid storage tank 7 and the first variable frequency radiator 2. Whether the first heat exchanger 31 or the third heat exchanger 33 is used as a condenser, the refrigerant flowing out of the condenser will first pass through the liquid storage tank 7 and then pass through the first variable frequency radiator 2. The liquid storage tank 7 always provides a stable and sufficient amount of refrigerant for the first variable frequency radiator 2 by storing the refrigerant, thereby ensuring the stable heat dissipation effect of the first variable frequency radiator 2.

[0079] Regarding the implementation of the flow direction adjusting valve group 6, in an embodiment, with reference to Figure 3, the flow direction adjusting valve group 6 comprises a first three-way valve 61, a second three-way valve 62, a third three-way valve 63, a fourth three-way valve 64, a first one-way valve 65, a second one-way valve 66, a third one-way valve 67 and a fourth one-way valve 68, the first three-way valve 61 comprises the first total interface 611, a first branch interface 612 and a second branch interface 613; the second three-way valve 62 comprises the second total interface 621, a third branch interface 622 and a fourth branch interface 623; the third three-way valve 63 comprises the third total interface 631, a fifth branch interface 632 and a sixth branch interface 633; the fourth three-way valve 64 comprises the fourth total interface 641, a seventh branch interface 642 and an eighth branch interface 643; the first one-way valve 65 is connected between the first branch interface 612 and the fifth branch interface 632 and opens from the first branch interface 612 to the fifth branch interface 632; the second one-way valve 66 is connected between the seventh branch interface 642 and the second branch interface 613 and opens from the seventh branch interface 642 to the second branch interface 613; the third one-way valve 67 is connected between the eighth branch interface 643 and the third branch interface 622 and opens from the eighth branch interface 643 to the third branch interface 622; the fourth one-way valve 68 is connected between the fourth branch interface 623 and the sixth branch interface 633 and opens from the fourth branch interface 623 to the sixth branch interface 633.

[0080] Based on the above flow direction adjusting valve group 6, referring to Figure 5 In the refrigeration mode, the refrigerant flows out of the third heat exchanger 33, flows to the liquid accumulator 7 through the second three-way valve 62-the fourth one-way valve 68-the third three-way valve 63, and then flows to the first heat exchanger 31 through the fourth three-way valve 64-the second one-way valve 66-the first three-way valve 61 after passing through the first variable frequency radiator 2. Referring to Figure 6 In the heating mode, the refrigerant flows out of the first heat exchanger 31, flows to the liquid accumulator 7 through the first three-way valve 61-the first one-way valve 65-the third three-way valve 63, and then flows to the third heat exchanger 33 through the fourth three-way valve 64-the third one-way valve 67-the second three-way valve 62 after passing through the first variable frequency radiator 2. Referring to Figure 7 In the heating defrosting mode, the refrigerant flows in the same way as in the refrigeration mode.

[0081] As can be seen from the above, no matter which mode is turned on, the refrigerant always passes through the liquid accumulator 7 first and then passes through the first variable frequency radiator 2, which guarantees the stable heat dissipation effect of the first variable frequency radiator 2.

[0082] Further, referring to Figure 1 A fifth one-way valve 83 is arranged in the connecting pipeline between the second heat exchanger 32 and the liquid accumulator 7, and the fifth one-way valve 83 opens from the second heat exchanger 32 to the liquid accumulator 7.

[0083] The second heat exchanger 32 is only for providing hot water, therefore it is generally used only as a condenser. Figure 8 and Figure 9 When the second heat exchanger 32 is activated, the refrigerant output from the second heat exchanger 32 can pass through the pipeline to the fifth one-way valve 83 and then to the liquid storage tank 7, and then through the first variable frequency radiator 2 to the third heat exchanger 33 or the first heat exchanger 31. Therefore, in both hot water + cooling mode and hot water mode, the refrigerant can always pass through the liquid storage tank 7 first and then through the first variable frequency radiator 2, ensuring the stable heat dissipation effect of the first variable frequency radiator 2.

[0084] Reference Figure 5 , Figure 6 , Figure 7 as well as Figure 9 Based on the setting of the fifth one-way valve 83, when the cooling mode, heating mode, heating defrosting mode and hot water defrosting mode are turned on, the fifth one-way valve 83 can cut off the pipeline between the liquid storage tank 7 and the second heat exchanger 32, so as to avoid the refrigerant flowing back into the second heat exchanger 32 and causing the system refrigerant to be insufficient.

[0085] In a further embodiment, refer to Figure 1 The connecting pipe between the first heat exchanger 31 and the first main interface 611 is provided with a sixth one-way valve 91 and a first throttle valve 92 connected in parallel. The sixth one-way valve 91 opens from the first heat exchanger 31 toward the first main interface 611. The connecting pipe between the third heat exchanger 33 and the second main interface 621 is provided with a seventh one-way valve 93 and a second throttle valve 94 connected in parallel. The seventh one-way valve 93 opens from the third heat exchanger 33 toward the second main interface 621.

[0086] That is, a sixth check valve 91 and a first throttle valve 92 are connected in parallel between the first heat exchanger 31 and the flow direction regulating valve group 6, and a seventh check valve 93 and a second throttle valve 94 are connected in parallel between the third heat exchanger 33 and the flow direction regulating valve group 6. By utilizing the reverse shut-off function of the sixth check valve 91 and the seventh check valve 93, the refrigerant can flow through the first variable frequency radiator 2 first, and then be throttled and depressurized by the throttle valve, regardless of the mode being opened, so as to ensure that there is always sufficient refrigerant in the pipeline of the first variable frequency radiator 2.

[0087] Specifically, refer to Figure 5 and Figure 7 When the cooling mode or heating / defrosting mode is activated, the seventh check valve 93 is forward-opening, and the sixth check valve 91 is reverse-closed. The refrigerant does not pass through the second throttling valve 94, but instead passes through the first throttling valve 92 for pressure reduction. (Refer to...) Figure 5 When the heating mode is turned on, the sixth one-way valve 91 is open in the forward direction and the seventh one-way valve 93 is closed in the reverse direction. The refrigerant does not pass through the first throttling valve 92, but is throttled and depressurized through the second throttling valve 94.

[0088] In one embodiment, the second heat exchanger 32 is connected with a fifth three-way valve 81 at one end away from the second four-way valve 5, the first total interface 611 and the connecting pipeline between the first heat exchanger 31 and the first total interface 611 are provided with a sixth three-way valve 82, one interface of the fifth three-way valve 81 is connected with the liquid storage tank 7, and the other interface is connected to the sixth three-way valve 82.

[0089] Specifically, among the three interfaces of the fifth three-way valve 81, one is connected with the second heat exchanger 32, and the other two are connected with the liquid storage tank 7 and the sixth three-way valve 82, respectively; among the three interfaces of the sixth three-way valve 82, one is connected with the fifth three-way valve 81, and the other two are connected with the first heat exchanger 31 and the first total interface 611, respectively, so that the connection between the flow regulating valve group 6 and the second heat exchanger 32 is established based on the fifth three-way valve 81 and the sixth three-way valve 82, and the flow direction of the refrigerant is adjusted by the flow regulating valve group 6. Figure 10 When the hot water defrosting mode is started, the refrigerant flowing out of the flow regulating valve group 6 can flow back into the second heat exchanger 32.

[0090] In the description herein, it should be understood that the terms "upper", "lower", "left", "right", and the like orientation or position relationship are only for the convenience of description and simplification of operation, and do not indicate or imply that the devices or elements referred to 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 used to distinguish in the description, and do not have special meanings.

[0091] In the description of the present specification, the description referring to the terms "one embodiment", "example", and the like means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are contained in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example.

[0092] In addition, it should be understood that although the present specification is described in terms of embodiments, each embodiment does not necessarily contain only one independent technical solution, and the description of the specification is only for the sake of clarity, and those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be appropriately combined to form other embodiments that those skilled in the art can understand.

[0093] The technical principles of the present application are described above in conjunction with specific embodiments. These descriptions are only for the purpose of explaining the principles of the present application, and cannot be interpreted in any way as a limitation on the scope of protection of the present application. Based on the explanations herein, those skilled in the art do not need to make creative efforts to conceive other specific embodiments of the present application, which will fall within the scope of protection of the present application.

Claims

1. A method for preventing freezing in a dual-unit, three-generation power supply system, characterized in that, The steps include: monitoring the temperature T1 of the heating side water circuit, the temperature T2 of the hot water circuit, and the ambient temperature T3; determining whether the heating side water circuit and the hot water circuit meet the conditions for triggering antifreeze protection; if they meet the conditions, switching the working mode of the first unit and / or the second unit so that at least one heat exchanger in the water circuit that triggers antifreeze protection enters the working state. Continuously monitor the temperature of the water circuit that has triggered the antifreeze protection to determine whether the conditions for exiting the antifreeze protection are met. If the conditions are met, stop supplying heat to that water circuit. When the water circuit that triggered the antifreeze protection meets the conditions for exiting the antifreeze protection, but the other water circuit has not yet met the conditions for exiting the antifreeze protection or the water temperature has not yet reached the set value, the unit that was originally supplying heat to the water circuit that had exited the antifreeze protection will be switched to supplying heat to the other water circuit.

2. The method for preventing freezing of dual-unit combined cooling, heating, and power systems according to claim 1, characterized in that, When T3≤a and T1≤b, the heating side meets the conditions for triggering antifreeze protection; when T3≤a and T2≤b, the hot water side meets the conditions for triggering antifreeze protection.

3. The method for preventing freezing of dual-unit combined cooling, heating, and power systems according to claim 2, characterized in that, When the monitoring duration of T1≥c reaches t, the heating side meets the conditions for exiting antifreeze protection; when the monitoring duration of T2≥c reaches t, the hot water side meets the conditions for exiting antifreeze protection.

4. The method for preventing freezing of dual-unit combined cooling, heating, and power systems according to claim 1, characterized in that, In standby mode, when both the heating and hot water circuits trigger antifreeze protection, the first unit starts to heat the heating circuit and the second unit starts to heat the hot water circuit. When one side of the heating and hot water circuits meets the conditions for exiting antifreeze protection, while the other side does not meet the conditions for exiting antifreeze protection, the first and second units are switched to simultaneously heat the water circuit that has not exited antifreeze protection.

5. The method for preventing freezing of dual-unit combined cooling, heating, and power systems according to claim 1, characterized in that, When operating in hot water mode, if the heating-side water circuit triggers antifreeze protection, the first unit will switch to supply heat to the heating-side water circuit; if the heating-side water circuit meets the conditions for exiting antifreeze protection and the hot water circuit temperature has not reached the set value, the first unit will switch to supply heat to the hot water circuit; if the heating-side water circuit does not meet the conditions for exiting antifreeze protection and the hot water circuit temperature has reached the set value, the second unit will switch to supply heat to the heating-side water circuit.

6. The method for preventing freezing of dual-unit combined cooling, heating, and power systems according to claim 1, characterized in that, When operating in heating mode, if the hot water circuit triggers the antifreeze protection, the first unit will switch to supply heat to the hot water circuit; if the hot water circuit meets the conditions for exiting the antifreeze protection and the temperature of the heating water circuit has not reached the set value, the first unit will switch to supply heat to the heating water circuit; if the hot water circuit does not meet the conditions for exiting the antifreeze protection and the temperature of the heating water circuit has reached the set value, the second unit will switch to supply heat to the hot water circuit.

7. A triple-unit heat pump for executing the control method of any one of claims 1-6, characterized in that, The system includes a first unit (100) and a second unit (200). The first unit (100) includes a first heat exchanger (31), a second heat exchanger (32) and a third heat exchanger (33). The second unit (200) includes a fourth heat exchanger (34), a fifth heat exchanger (35) and a sixth heat exchanger (36). The first heat exchanger (31) and the fourth heat exchanger (34) are both connected to the heating side water circuit (300). The second heat exchanger (32) and the fifth heat exchanger (35) are both connected to the hot water side water circuit (400). The third heat exchanger (33) and the sixth heat exchanger (36) are both finned heat exchangers.

8. The triple-unit heat pump according to claim 7, characterized in that, The first unit (100) further includes a first compressor (11), a first inverter board (21), and a first inverter radiator (2) mounted on the first inverter board (21). The first inverter radiator (2) is connected to the side of the first heat exchanger (31), the second heat exchanger (32), and the third heat exchanger (33) away from the first compressor (11), thereby using the liquid refrigerant output by the first heat exchanger (31), the second heat exchanger (32), or the third heat exchanger (33) to accelerate the first inverter. Frequency board (21) heat dissipation; the second unit (200) also includes a second compressor (12), a second frequency board and a second frequency radiator installed on the second frequency board. The second frequency radiator is connected to the side of the fourth heat exchanger (34), the fifth heat exchanger (35) and the sixth heat exchanger (36) away from the second compressor (12), so as to accelerate the heat dissipation of the second frequency board by using the liquid refrigerant output by the fourth heat exchanger (34), the fifth heat exchanger (35) or the sixth heat exchanger (36).

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