Non-azeotropic mixture refrigerant heat pump system and its control method

Abstract

The present invention relates to the field of heat pump technology, and discloses a non-azeotropic mixed working fluid heat pump system and a control method thereof, wherein an electric control valve group is used to control the heat pump system to operate in a first heat exchange mode or a second heat exchange mode. When the heat pump system is in the first heat exchange mode, the refrigerant flows through the condenser, the first heat exchange channel, the second throttling device, the evaporator, the second heat exchange channel, and the return air port of the compressor in sequence; when the heat pump system is in the second heat exchange mode, the refrigerant flows through the condenser, the first heat exchange channel, the first circulation branch and the second circulation branch in sequence, and the refrigerant on the first circulation branch flows through the second throttling device, the evaporator, and the return air port of the compressor in sequence, and the refrigerant on the second circulation branch flows through the third throttling device, the second heat exchange channel, and the air supply port of the compressor in sequence. The present invention can switch the heat exchange mode of the heat pump system according to changes in ambient temperature, so that the heat pump system can effectively reduce the overall energy consumption of the heat pump system while operating stably and meeting heating needs.

Description

Technical Field

[0001] The present invention relates to the technical field of heat pumps, and in particular to a non-azeotropic mixed working fluid heat pump system and a control method thereof. Background Art

[0002] With the advancement of technology and improvements in living standards, heat pump technology is increasingly being used in both homes and industry. Due to the wide temperature range between the heat source and heat sink in heat pump systems, traditional single refrigerants are unable to meet the requirements, such as ultra-low ambient temperature heating in buildings. Non-azeotropic refrigerant mixtures allow for flexible selection of refrigerant components and proportions based on the application, increasing the temperature difference between the heat source and heat sink, thereby meeting the wide temperature range requirements of specific applications.

[0003] However, when non-azeotropic mixed working fluids are applied to traditional heat pump systems, it is impossible to take into account both heating capacity and energy efficiency under low ambient temperature conditions. Therefore, there is room for improvement. Summary of the Invention

[0004] The technical problem solved by the present invention is to provide a non-azeotropic mixed working fluid heat pump system, which effectively solves the technical problems of poor heating performance and high energy consumption of the heat pump system.

[0005] The above technical problems are solved by the following technical solutions:

[0006] A non-azeotropic mixed working fluid heat pump system, comprising:

[0007] A refrigerant circulation loop connected to the exhaust port of the compressor and the return port of the compressor to form a loop, wherein a condenser, a heat exchanger, a second throttling device and an evaporator are sequentially arranged on the refrigerant circulation loop along the refrigerant flow direction;

[0008] The heat exchanger comprises a first heat exchange channel and a second heat exchange channel for mutual heat exchange, wherein the first heat exchange channel is connected between the outlet of the condenser and the inlet of the evaporator, and the second heat exchange channel is connected between the outlet of the evaporator and the return air port of the compressor;

[0009] The heat pump system further includes a third throttling device connected between the outlet of the first heat exchange channel and the inlet of the second heat exchange channel;

[0010] The heat pump system includes an electrically controlled valve group, which is used to control the heat pump system to operate in a first heat exchange mode or a second heat exchange mode;

[0011] In the first heat exchange mode, the refrigerant flows sequentially through the condenser, the first heat exchange channel, the second throttling device, the evaporator, the second heat exchange channel, and the return air port of the compressor;

[0012] In the second heat exchange mode, the refrigerant flows through the condenser and the first heat exchange channel in sequence. After flowing out from the outlet of the first heat exchange channel, the refrigerant flows along the first circulation branch and the second circulation branch respectively. The refrigerant on the first circulation branch flows through the second throttling device, the evaporator, and the return air port of the compressor in sequence. The refrigerant on the second circulation branch flows through the third throttling device, the second heat exchange channel, and the air supply port of the compressor in sequence.

[0013] Compared with the background technology, the non-azeotropic mixed refrigerant heat pump system described in the present invention has the following beneficial effects: in the first heat exchange mode, the non-azeotropic mixed refrigerant (i.e., refrigerant) enters the condenser for cooling after being discharged from the compressor outlet, and after cooling, the non-azeotropic mixed refrigerant is transmitted along the connecting pipeline to the first heat exchange channel of the heat exchanger for cooling; the cooled refrigerant passes through the second throttling device along the connecting pipeline for throttling, and then enters the evaporator. After heat exchange in the evaporator, the mixed refrigerant flows from the evaporator outlet into the second heat exchange channel of the heat exchanger to cool the mixed refrigerant flowing from the condenser into the first heat exchange channel, and then the mixed refrigerant is transmitted to the compressor through the return air port of the compressor.

[0014] In the second heat exchange mode, the non-azeotropic mixture is discharged from the compressor outlet and enters the condenser for cooling. After cooling, the non-azeotropic mixture is transmitted along the connecting pipeline to the first heat exchange channel of the heat exchanger for cooling; when the refrigerant flows out from the outlet of the first heat exchange channel, the refrigerant continues to flow along the first circulation branch and the second circulation branch respectively; when the refrigerant flows along the first circulation branch, the mixture passes through the second throttling device along the connecting pipeline for throttling, and then enters the evaporator. After heat exchange in the evaporator, the mixture flows out from the evaporator outlet and is transmitted to the compressor through the return air port of the compressor; when the refrigerant flows along the second circulation branch, the mixture passes through the third throttling device along the connecting pipeline for throttling, and the throttled mixture is then transmitted to the second heat exchange channel of the heat exchanger to cool the mixture flowing from the condenser into the first heat exchange channel, and then the mixture is transmitted to the compressor through the air supply port of the compressor.

[0015] The non-azeotropic mixture heat pump system disclosed in the present invention can select different heat exchange modes according to the actual ambient temperature. When the ambient temperature is relatively high, the heat pump system is controlled to operate in the first heat exchange mode. During the refrigerant circulation process, the evaporator absorbs heat from the air, and combined with the work of the compressor, the two parts of energy are finally released in the condenser, so that the heat pump system heats and raises the water temperature. Moreover, in the process of the non-azeotropic mixture being transmitted from the condenser outlet to the evaporator inlet, the mixture undergoes throttling and heat recovery once, so that the throttling temperature difference from the condenser to the evaporator is greatly reduced compared with the traditional heat pump system, and finally the throttling loss is greatly reduced, thereby improving the heating performance of the non-azeotropic mixture heat pump system.

[0016] When the ambient temperature is relatively low, the compressor pressure ratio increases, causing the exhaust temperature to increase. Therefore, the heat pump system is controlled to operate in the second heat exchange mode. During the refrigerant circulation process, the mixed working fluid is throttled by the third throttling device and flows into the second heat exchange channel of the heat exchanger. It then flows into the air supply port of the compressor to supply air to the compressor, thereby reducing the compressor pressure ratio to reduce the compressor exhaust temperature, making the heat pump system more stable and efficient at low ambient temperatures. The refrigerant in the first circulation branch and the refrigerant in the second circulation branch exchange heat in the heat exchanger, thereby effectively reducing the temperature of the mixed working fluid flowing out of the first heat exchange channel, so that the mixed working fluid is further supercooled before entering the evaporator, thereby effectively improving the heating effect of the heat pump system and meeting the higher indoor heating demand under low ambient temperature conditions. According to the change in ambient temperature, the non-azeotropic mixed working fluid heat pump system is controlled to switch between the first heat exchange mode and the second heat exchange mode, so that the heat pump system can effectively reduce the overall energy consumption of the heat pump system while operating stably and meeting the heating demand, thereby improving the user experience.

[0017] In one embodiment, it further includes:

[0018] The first throttling device is connected between the outlet of the condenser and the inlet of the first heat exchange channel; the second throttling device is connected between the outlet of the first heat exchange channel and the inlet of the evaporator.

[0019] In one embodiment, the electrically controlled valve group includes a first electrically controlled valve, a second electrically controlled valve and a fourth electrically controlled valve, wherein the first electrically controlled valve is arranged between the outlet of the evaporator and the return air port of the compressor; the second electrically controlled valve is arranged between the outlet of the second heat exchange channel and the air supply port of the compressor; and the fourth electrically controlled valve is arranged between the outlet of the second heat exchange channel and the return air port of the compressor.

[0020] In one embodiment, the electrically controlled valve group further includes a third electrically controlled valve, and the third electrically controlled valve is connected between the outlet of the evaporator and the inlet of the second heat exchange channel.

[0021] In one embodiment, it further includes:

[0022] The liquid reservoir is provided with a refrigerant inlet, a first refrigerant outlet and a second refrigerant outlet. The refrigerant inlet is connected to the first throttling device, the first refrigerant outlet is connected to the inlet of the first heat exchange channel, and the second refrigerant outlet is connected to the inlet of the evaporator through a bypass line. A fifth electric control valve is provided on the bypass line.

[0023] In one embodiment, the first throttling device, the second throttling device and the third throttling device are all expansion valves.

[0024] In one embodiment, a gas-liquid separator is further provided on the refrigerant circulation loop, the inlet of the gas-liquid separator is respectively connected to the outlet of the second heat exchange channel and the outlet of the evaporator, and the outlet of the gas-liquid separator is connected to the return air port of the compressor.

[0025] In one embodiment, the air conditioner further includes an evaporator fan, wherein the evaporator fan is used to drive air to flow through the evaporator.

[0026] On the other hand, the present invention further provides a control method for a non-azeotropic mixed working fluid heat pump system, which is applied to the non-azeotropic mixed working fluid heat pump system. The control method includes:

[0027] Acquiring an ambient temperature, and comparing the ambient temperature with a first target temperature and a second target temperature, respectively, wherein the first target temperature is greater than the second target temperature;

[0028] When the ambient temperature is greater than or equal to the first target temperature, controlling the electrically controlled valve group to operate so that the heat pump system operates in the first heat exchange mode;

[0029] When the ambient temperature is less than or equal to the second target temperature, the electrically controlled valve group is controlled to operate so that the heat pump system operates in the second heat exchange mode.

[0030] Compared with the background technology, the control method of the non-azeotropic mixed refrigerant heat pump system disclosed in the present invention has the following beneficial effects: the non-azeotropic mixed refrigerant heat pump system disclosed in the present invention can select different heat exchange modes according to the actual ambient temperature. When the ambient temperature is greater than or equal to the first target temperature, the heat pump system is operated in the first heat exchange mode by controlling the electric control valve group; the refrigerant is caused to flow through the condenser, the first heat exchange channel, the second throttling device, the evaporator, the second heat exchange channel and the return air port of the compressor in sequence. During the refrigerant circulation process, the evaporator absorbs heat from the air, and the compressor works, so that the two parts of energy are finally released in the condenser, so that the heat pump system heats and raises the water temperature. Moreover, in the process of the non-azeotropic mixed refrigerant being transmitted from the condenser outlet to the evaporator inlet, the mixed refrigerant undergoes throttling and heat recovery once, so that the throttling temperature difference from the condenser to the evaporator is greatly reduced compared with the traditional heat pump system, and finally the throttling loss is greatly reduced, thereby improving the heating performance of the non-azeotropic mixed refrigerant heat pump system.

[0031] When the ambient temperature is less than or equal to the second target temperature, the heat pump system is operated in the second heat exchange mode by controlling the electronically controlled valve group; the refrigerant is caused to flow through the condenser and the first heat exchange channel in sequence, and after the refrigerant flows out from the outlet of the first heat exchange channel, it flows along the first circulation branch and the second circulation branch respectively; wherein, the refrigerant on the first circulation branch flows through the second throttling device, the evaporator and the return air port of the compressor in sequence, and the refrigerant on the second circulation branch flows through the third throttling device, the second heat exchange channel and the air supply port of the compressor in sequence. During the refrigerant circulation process, the mixed working fluid flows into the second heat exchange channel of the heat exchanger after being throttled by the third throttling device, and then flows into the air supply port of the compressor to supply air to the compressor, thereby reducing the compressor pressure ratio to reduce the compressor exhaust temperature, making the heat pump system more stable and efficient at low ambient temperatures, and the first circulation branch refrigerant and the second circulation branch refrigerant exchange heat in the heat exchanger, thereby effectively reducing the temperature of the mixed working fluid flowing out of the first heat exchange channel, so that the mixed working fluid is further supercooled before entering the evaporator, thereby effectively improving the heating effect of the heat pump system, and can meet higher indoor heating needs under low ambient temperatures. By switching the non-azeotropic mixed working fluid heat pump system between the first heat exchange mode and the second heat exchange mode, the heat pump system can effectively reduce the overall energy consumption of the heat pump system while operating stably and meeting the heating needs, thereby improving the user experience.

[0032] In one embodiment, the electrically controlled valve group includes a first electrically controlled valve, a second electrically controlled valve, a third electrically controlled valve, and a fourth electrically controlled valve, wherein the first electrically controlled valve is arranged between the outlet of the evaporator and the return air port of the compressor; the second electrically controlled valve is arranged between the outlet of the second heat exchange channel and the air supply port of the compressor; the third electrically controlled valve is connected between the outlet of the evaporator and the inlet of the second heat exchange channel; the fourth electrically controlled valve is arranged between the outlet of the second heat exchange channel and the return air port of the compressor; the heat pump system further includes a first throttling device connected between the outlet of the condenser and the inlet of the first heat exchange channel;

[0033] The method further comprises:

[0034] When the heat pump system operates in the first heat exchange mode, controlling the first throttling device, the second throttling device, the third electrically controlled valve, and the fourth electrically controlled valve to be in an open state, and controlling the third throttling device, the first electrically controlled valve, and the second electrically controlled valve to be in a closed state;

[0035] When the heat pump system operates in the second heat exchange mode, the first throttling device, the second throttling device, the third throttling device, the first electrically controlled valve and the second electrically controlled valve are controlled to be in an open state, and the third electrically controlled valve and the fourth electrically controlled valve are controlled to be in a closed state.

[0036] In one embodiment, the method further comprises:

[0037] When the ambient temperature is greater than the second target temperature and less than the first target temperature, the heat pump system is controlled to operate in a current mode, where the current mode includes the first heat exchange mode and the second heat exchange mode.

[0038] In one embodiment, the heat pump system further includes a liquid reservoir and an evaporator fan for driving air to flow through the evaporator, the liquid reservoir is provided with a refrigerant inlet, a first refrigerant outlet, and a second refrigerant outlet, the refrigerant inlet is connected to the first throttling device, the first refrigerant outlet is connected to the inlet of the first heat exchange channel, and the second refrigerant outlet is connected to the inlet of the evaporator via a bypass line, and the bypass line is provided with a fifth electrically controlled valve;

[0039] The method further comprises:

[0040] comparing the ambient temperature with a third target temperature, the third target temperature being lower than the second target temperature;

[0041] When the ambient temperature is lower than the third target temperature, the first electrically controlled valve, the fifth electrically controlled valve, and the first throttling device are controlled to be in an open state, and the first throttling device is controlled to be opened to a maximum opening, and the second throttling device, the third throttling device, the second electrically controlled valve, the third electrically controlled valve, the fourth electrically controlled valve, and the evaporator fan are controlled to be in a closed state;

[0042] When the ambient temperature is greater than or equal to the third target temperature, the fifth electrically controlled valve, the third electrically controlled valve and the fourth electrically controlled valve are controlled to be in a closed state, and the first throttling device, the second throttling device, the third throttling device, the first electrically controlled valve, the second electrically controlled valve and the evaporator fan are controlled to be in an open state.

[0043] In one embodiment, the method further comprises:

[0044] In response to the heat pump system being in a defrost mode, detecting the evaporator outlet temperature, and comparing the evaporator outlet temperature with a fourth target temperature;

[0045] When the evaporator outlet temperature is greater than or equal to the fourth target temperature, controlling the evaporator fan, the first throttling device, the second throttling device, the third throttling device, the first electrically controlled valve, and the second electrically controlled valve to be opened, and controlling the fifth electrically controlled valve, the third electrically controlled valve, and the fourth electrically controlled valve to be closed, so as to switch to the second heat exchange mode;

[0046] When the evaporator outlet temperature is lower than the fourth target temperature, the evaporator fan, the second throttling device, the third throttling device, the second electrically controlled valve, the third electrically controlled valve and the fourth electrically controlled valve are controlled to be in a closed state, and the first electrically controlled valve, the fifth electrically controlled valve and the first throttling device are controlled to be in an open state to maintain the defrost mode. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0048] Figure 1 This is a schematic structural diagram of a non-azeotropic mixed working fluid heat pump system according to an embodiment of the present invention;

[0049] Figure 2 This is a schematic structural diagram of a non-azeotropic mixed working fluid heat pump system according to another embodiment of the present invention;

[0050] Figure 3 This is a schematic structural diagram of a non-azeotropic mixed working fluid heat pump system according to another embodiment of the present invention;

[0051] Figure 4 This is a schematic structural diagram of a non-azeotropic mixed working fluid heat pump system according to another embodiment of the present invention;

[0052] Figure 5 Schematic diagram of a flow chart of a control method for a non-azeotropic mixed working fluid heat pump system according to an embodiment of the present invention;

[0053] Figure 6 1 is a flow chart of a control method for a non-azeotropic mixed working fluid heat pump system according to another embodiment of the present invention;

[0054] Figure 7 1 is a flow chart of a control method for a non-azeotropic mixed working fluid heat pump system according to another embodiment of the present invention;

[0055] Figure 8 1 is a flow chart of a control method for a non-azeotropic mixed working fluid heat pump system according to another embodiment of the present invention;

[0056] Figure 9 This is a structural schematic diagram of a non-azeotropic mixed working fluid heat pump system according to another embodiment of the present invention.

[0057] Description of reference numerals:

[0058] 1. Compressor; 2. Condenser; 3. First throttling device; 4. Liquid accumulator; 41. Bypass line; 42. Refrigerant inlet; 43. First refrigerant outlet; 44. Second refrigerant outlet; 5. Fifth electric-controlled valve; 6. Heat exchanger; 61. First heat exchange channel; 62. Second heat exchange channel; 7. Third throttling device; 8. Second throttling device; 9. Evaporator; 10. Fourth electric-controlled valve; 11. Third electric-controlled valve; 12. First electric-controlled valve; 13. Second electric-controlled valve; 14. Gas-liquid separator; 15. Evaporator fan. DETAILED DESCRIPTION

[0059] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0060] In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly indicate the number of the indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "plurality" means two or more. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0061] According to an embodiment of the present invention, Figures 1 to 3As shown, on the one hand, a non-azeotropic mixed working fluid heat pump system is provided, comprising: a refrigerant circulation loop connected to the exhaust port of the compressor 1 and the return air port of the compressor 1 to form a loop, and a condenser 2, a heat exchanger 6, a second throttling device 8 and an evaporator 9 are sequentially arranged on the refrigerant circulation loop along the flow direction of the refrigerant; the heat exchanger 6 has a first heat exchange channel 61 and a second heat exchange channel 62 for mutual heat exchange, the first heat exchange channel 61 is connected between the outlet of the condenser 2 and the inlet of the evaporator 9, and the second heat exchange channel 62 is connected between the outlet of the evaporator 9 and the return air port of the compressor 1; the heat pump system also includes a third throttling device 7, and the third throttling device 7 is connected between the outlet of the first heat exchange channel 61 and the inlet of the second heat exchange channel 62; the heat pump system The system includes an electrically controlled valve group, which is used to control the heat pump system to operate in a first heat exchange mode or a second heat exchange mode; in the first heat exchange mode, the refrigerant flows through the condenser 2, the first heat exchange channel 61, the second throttling device 8, the evaporator 9, the second heat exchange channel 62, and the return air port of the compressor 1 in sequence; in the second heat exchange mode, the refrigerant flows through the condenser 2 and the first heat exchange channel 61 in sequence, and after the refrigerant flows out from the outlet of the first heat exchange channel 61, it flows along the first circulation branch and the second circulation branch respectively. The refrigerant on the first circulation branch flows through the second throttling device 8, the evaporator 9, and the return air port of the compressor 1 in sequence, and the refrigerant on the second circulation branch flows through the third throttling device 7, the second heat exchange channel 62, and the air supply port of the compressor 1 in sequence.

[0062] In this embodiment, arrows in the figure indicate the direction of refrigerant flow. Specifically, the refrigerant can be a non-azeotropic mixture. The heat exchange modes of the non-azeotropic mixture heat pump system provided in this embodiment of the present invention include a first heat exchange mode and a second heat exchange mode. Specifically, the heat pump system can be controlled to operate in different heat exchange modes based on the actual ambient temperature.

[0063] In the first heat exchange mode, the specific heating principle is as follows: Compressor 1 compresses low-pressure, low-temperature refrigerant gas into high-pressure, high-temperature gas. The high-pressure, high-temperature refrigerant gas enters condenser 2, where it undergoes heat exchange with the medium to be heated (such as indoor air or water), transferring heat to the indoor air or water to achieve the heating effect. After the heat exchange, the refrigerant's own temperature and pressure decrease, becoming a high-pressure, low-temperature gas-liquid mixture. The non-azeotropic mixture is transported along a connecting pipeline to the first heat exchange channel 61 of heat exchanger 6 for cooling. The cooled refrigerant then passes through second throttling device 8 along the connecting pipeline, where it is throttled, further reducing the refrigerant's pressure and temperature. After throttling, the mixture becomes a pure liquid, ready for heat exchange in evaporator 9. The non-azeotropic mixed working medium then passes through the second throttling device 8 and flows into the evaporator 9 along the connecting pipeline; the liquid working medium absorbs heat in the evaporator 9, then flows out from the outlet of the evaporator 9, and flows into the second heat exchange channel 62 along the connecting pipeline to cool the mixed working medium flowing from the condenser 2 into the first heat exchange channel 61. The mixed working medium is then transmitted to the compressor 1 through the return air port of the compressor 1 and continues to circulate through the compressor 1.

[0064] During the refrigerant circulation process, the evaporator 9 absorbs heat from the air, and combined with the work of the compressor 1, the two parts of energy are finally released in the condenser 2, so that the heat pump system heats and raises the water temperature. Moreover, in the process of the non-azeotropic mixed working fluid being transmitted from the outlet of the condenser 2 to the inlet of the evaporator 9, the mixed working fluid undergoes throttling and heat recovery once, which greatly reduces the throttling temperature difference from the condenser 2 to the evaporator 9 compared with the traditional heat pump system, and ultimately greatly reduces the throttling loss, thereby improving the heating performance of the non-azeotropic mixed working fluid heat pump system.

[0065] In the second heat exchange mode, the specific heating operating principle is as follows: Compressor 1 compresses low-pressure, low-temperature refrigerant gas into high-pressure, high-temperature gas. This high-pressure, high-temperature refrigerant gas enters condenser 2, where it undergoes heat exchange with the medium to be heated (such as indoor air or water), transferring heat to the indoor air or water, achieving a heating effect. After the heat exchange, the refrigerant's temperature and pressure decrease, becoming a high-pressure, low-temperature gas-liquid mixture. The non-azeotropic mixture is then transported via a connecting pipeline to the first heat exchange channel 61 of heat exchanger 6 for cooling. After exiting the outlet of the first heat exchange channel 61, the mixture continues to flow through the first and second circulation branches, respectively. While flowing along the first circulation branch, the mixture passes through the second throttling device 8 along the connecting pipeline, where it is throttled, further reducing the refrigerant's pressure and temperature. After throttling through the second throttling device 8, the mixture becomes a pure liquid, ready for heat exchange in the evaporator 9. The non-azeotropic mixed working medium then passes through the second throttling device 8 and flows along the connecting pipe into the evaporator 9; the liquid working medium absorbs heat in the evaporator 9, then flows out of the outlet of the evaporator 9 and is transferred to the compressor 1 through the return air port of the compressor 1. When the mixed working medium flows along the second circulation branch, the mixed working medium is transferred along the connecting pipe to the third throttling device 7 for throttling. The throttled mixed working medium is then transferred to the second heat exchange channel 62 of the heat exchanger 6 to cool the mixed working medium flowing from the condenser 2 into the first heat exchange channel 61. The mixed working medium is then transferred to the compressor 1 through the air supply port of the compressor 1.

[0066] During the refrigerant circulation process, the mixed working fluid flows into the second heat exchange channel 62 of the heat exchanger 6 after being throttled by the third throttling device 7, and then flows into the air supply port of the compressor 1 to supply air to the compressor 1, thereby reducing the pressure ratio of the compressor 1 to reduce the exhaust temperature of the compressor 1, so that the heat pump system can operate more stably and efficiently under low ambient temperature. In addition, the first circulation branch refrigerant and the second circulation branch refrigerant exchange heat in the heat exchanger 6, thereby effectively reducing the temperature of the mixed working fluid flowing out of the first heat exchange channel 61, so that the mixed working fluid is further supercooled before entering the evaporator 9, thereby effectively improving the heating effect of the heat pump system, and can meet the higher indoor heating demand under low ambient temperature. According to the change of ambient temperature, the non-azeotropic mixed working fluid heat pump system is controlled to switch between the first heat exchange mode and the second heat exchange mode, so that the heat pump system can effectively reduce the overall energy consumption of the heat pump system when it operates stably and meets the heating demand, thereby improving the user experience.

[0067] In one embodiment, it further includes: a first throttling device 3, which is connected between the outlet of the condenser 2 and the inlet of the first heat exchange channel 61; and a second throttling device 8 which is connected between the outlet of the first heat exchange channel 61 and the inlet of the evaporator 9.

[0068] In this embodiment, one end of the first throttling device 3 is connected to the outlet of the condenser 2, and the other end is connected to the inlet of the first heat exchange channel 61. After the mixed working medium flows out of the condenser 2, it can be throttled by the first throttling device 3 to reduce the pressure of the mixed working medium. One end of the second throttling device 8 is connected to the outlet of the first heat exchange channel 61, and the other end is connected to the inlet of the evaporator 9. After the mixed working medium flows out of the first heat exchange channel 61, it can be throttled by the second throttling device 8 to further reduce the pressure and temperature of the mixed working medium. After throttling by the second throttling device 8, the mixed working medium becomes a pure liquid state, ready for heat exchange in the evaporator 9.

[0069] In one embodiment, the electrically controlled valve group includes a first electrically controlled valve 12, a second electrically controlled valve 13 and a fourth electrically controlled valve 10. The first electrically controlled valve 12 is arranged between the outlet of the evaporator 9 and the return air port of the compressor 1; the second electrically controlled valve 13 is arranged between the outlet of the second heat exchange channel 62 and the air supply port of the compressor 1; and the fourth electrically controlled valve 10 is arranged between the outlet of the second heat exchange channel 62 and the return air port of the compressor 1.

[0070] Furthermore, the electrically controlled valve group includes a third electrically controlled valve 11 , which is connected between the outlet of the evaporator 9 and the inlet of the second heat exchange channel 62 .

[0071] In this embodiment, the first electrically controlled valve 12, the second electrically controlled valve 13, the third electrically controlled valve 11, and the fourth electrically controlled valve 10 cooperate to control the on-off of the refrigerant circulation circuit in the heat pump system to change the heating operation mode of the heat pump system. When the third electrically controlled valve 11 and the fourth electrically controlled valve 10 are in the open state, the connecting pipelines between the outlet of the evaporator 9 and the inlet of the second heat exchange channel 62, as well as the connecting pipelines between the outlet of the second heat exchange channel 62 and the return air port of the compressor 1, are connected; when the first electrically controlled valve 12, the second electrically controlled valve 13, and the third throttling device 7 are in the closed state, the connecting pipeline between the outlet of the first heat exchange channel 61 and the inlet of the second heat exchange channel 62, the connecting pipeline between the outlet of the second heat exchange channel 62 and the air supply port of the compressor 1, and the other connecting pipeline between the outlet of the evaporator 9 and the return air port of the compressor 1 are all disconnected. At this time, the heat pump system is in the first heat exchange mode. The refrigerant in the refrigerant circulation loop is discharged from the exhaust port of the compressor 1 and flows through the condenser 2, the first throttling device 3, the first heat exchange channel 61, the second throttling device 8, the evaporator 9, the third electric control valve 11, the second heat exchange channel 62, the fourth electric control valve 10 and the return air port of the compressor 1 in sequence.

[0072] When the third electrically controlled valve 11 and the fourth electrically controlled valve 10 are in the closed state, the connecting pipelines between the outlet of the evaporator 9 and the inlet of the second heat exchange channel 62, and the outlet of the second heat exchange channel 62 and the return air port of the compressor 1 are disconnected; when the first electrically controlled valve 12, the second electrically controlled valve 13 and the third throttling device 7 are in the open state, the connecting pipeline between the outlet of the first heat exchange channel 61 and the inlet of the second heat exchange channel 62, the connecting pipeline between the outlet of the second heat exchange channel 62 and the air supply port of the compressor 1, and another connecting pipeline between the outlet of the evaporator 9 and the return air port of the compressor 1 are all in a connected state. At this time, the heat pump system is in the second heat exchange mode. The refrigerant in the refrigerant circulation loop is discharged from the exhaust port of the compressor 1 and flows through the condenser 2, the first throttling device 3, and the first heat exchange channel 61 in sequence. After the refrigerant flows out from the outlet of the first heat exchange channel 61, it flows along the first circulation branch and the second circulation branch respectively. The refrigerant on the first circulation branch flows through the second throttling device 8, the evaporator 9, the first electric control valve 12 and the return air port of the compressor 1 in sequence; at the same time, the refrigerant on the second circulation branch flows through the third throttling device 7, the second heat exchange channel 62, the second electric control valve 13 and the air supply port of the compressor 1 in sequence.

[0073] like Figure 4 As shown, in one embodiment, it also includes: a liquid reservoir 4, the liquid reservoir 4 is provided with a refrigerant inlet 42, a first refrigerant outlet 43 and a second refrigerant outlet 44, the refrigerant inlet 42 is connected to the first throttling device 3, the first refrigerant outlet 43 is connected to the inlet of the first heat exchange channel 61, and the second refrigerant outlet 44 is connected to the inlet of the evaporator 9 through the bypass line 41, and the bypass line 41 is provided with a fifth electric control valve 5.

[0074] In this embodiment, due to the low ambient temperature, the evaporation capacity of the unit is weakened, and therefore, the evaporator 9 may be frosted in a low temperature environment. When the non-azeotropic mixed refrigerant heat pump system is in defrost mode, the fifth electric control valve 5 is opened and the opening of the first throttling device 3 is maximized, and the second throttling device 8, the third throttling device 7, the second electric control valve 13, the third electric control valve 11 and the fourth electric control valve 10 are all controlled to be in a closed state; the gaseous refrigerant in the non-azeotropic mixed refrigerant heat pump system is discharged through the second refrigerant outlet 44 and enters the bypass line 41. Then, in the refrigerant circulation loop, the refrigerant in the compressor 1 flows to the condenser 2, the first throttling device 3, the liquid reservoir 4, the fifth electric control valve 5, the evaporator 9, the first electric control valve 12, and the compressor 1.

[0075] The specific defrosting working principle is as follows: the compressor 1 compresses the low-pressure, low-temperature refrigerant gas into a high-pressure, high-temperature gas. The high-pressure, high-temperature refrigerant gas enters the condenser 2, where it undergoes heat exchange with the medium to be heated, transferring heat to the indoor air or water to achieve a heating effect. After the heat exchange, the temperature and pressure of the refrigerant itself decrease, turning it into a high-pressure, low-temperature gas-liquid mixture. The low-boiling-point refrigerant is mostly gaseous, while the high-boiling-point refrigerant is mostly liquid. The gas-liquid mixed refrigerant passes through the first throttling device 3. Since the opening of the first throttling device 3 is adjusted to the maximum, the throttling effect is poor, and the effect on the temperature of the mixed refrigerant is small. The gas-liquid mixed refrigerant enters the liquid reservoir 4 through the refrigerant inlet 42 and is separated. In the liquid reservoir 4, most of the gaseous refrigerant is discharged from the second refrigerant outlet 44 of the liquid reservoir 4 into the bypass line 41, and is transported to the evaporator 9 through the fifth electrically controlled valve 5 for defrosting. It is then sucked into the compressor 1 and continues to circulate through the compressor 1. From then on, a defrosting cycle is completed.

[0076] During the defrost cycle, since the opening of the first throttling device 3 is adjusted to the maximum, the non-azeotropic mixture refrigerant still has a high pressure and temperature after flowing through the first throttling device 3, and most of the low-boiling-point refrigerant is in gaseous state. When the gaseous refrigerant is condensed in the evaporator 9, a large amount of heat will be released for defrosting; according to the characteristics of the non-azeotropic mixture refrigerant, the low-boiling-point component in the gaseous refrigerant accounts for a large proportion, that is, the refrigerant component actually participating in the entire defrost cycle accounts for a large proportion compared with the low-boiling-point component in the heating cycle, and since the density of the low-boiling-point refrigerant is greater than the density of the high-boiling-point refrigerant, the high pressure and mass flow rate of the refrigerant in the defrost cycle are increased, which ultimately makes the compressor 1 do more work, that is, the condensation heat dissipation of the evaporator 9 defrosting is greater, thereby effectively improving the defrost effect of the non-azeotropic mixture refrigerant heat pump system.

[0077] Furthermore, in the first heat exchange mode, the specific heating working principle is: the compressor 1 compresses the low-pressure and low-temperature refrigerant gas into a high-pressure and high-temperature gas, and the high-pressure and high-temperature refrigerant gas enters the condenser 2, and exchanges heat with the medium to be heated (such as indoor air or water) in the condenser 2, and transfers heat to the indoor air or water to achieve a heating effect. Thereafter, the gas-liquid mixture rapidly expands after throttling by the first throttling device 3, and then enters the liquid reservoir 4 through the refrigerant inlet 42; the gas-liquid mixed working medium continues to be discharged from the first refrigerant outlet 43, and flows along the connecting pipeline to the first heat exchange channel 61 connected to the liquid reservoir 4, so as to enter the first heat exchange channel 61 of the heat exchanger 6 for cooling; the cooled working medium passes through the second throttling device 8 along the connecting pipeline for throttling, further reducing the pressure and temperature of the refrigerant, so that the mixed working medium becomes a pure liquid state after throttling by the second throttling device 8, and is ready for heat exchange in the evaporator 9. The non-azeotropic mixed working medium then passes through the second throttling device 8 and flows into the evaporator 9 along the connecting pipeline; the liquid working medium absorbs heat in the evaporator 9, then flows out from the outlet of the evaporator 9 and flows into the second heat exchange channel 62 along the connecting pipeline to flow into the heat exchanger 6 and cool the mixed working medium coming out of the liquid reservoir 4 in the heat exchanger 6; then the mixed working medium flows out of the second heat exchange channel 62 and is transmitted to the compressor 1 through the return air port of the compressor 1, and continues to circulate through the compressor 1.

[0078] In the second heat exchange mode, the specific heating working principle is as follows: the compressor 1 compresses the low-pressure and low-temperature refrigerant gas into a high-pressure and high-temperature gas, and the high-pressure and high-temperature refrigerant gas enters the condenser 2, and exchanges heat with the medium to be heated (such as indoor air or water) in the condenser 2, and transfers heat to the indoor air or water to achieve a heating effect. After the heat exchange, the temperature and pressure of the refrigerant itself decrease, and then the gas-liquid mixture is throttled by the first throttling device 3 and rapidly expands, and then enters the liquid reservoir 4 through the refrigerant inlet 42; the gas-liquid mixed working medium continues to be discharged from the first refrigerant outlet 43, and flows along the connecting pipeline to the first heat exchange channel 61 connected to the liquid reservoir 4, so as to enter the first heat exchange channel 61 of the heat exchanger 6 for cooling; the cooled working medium passes through the second throttling device 8 along the connecting pipeline for throttling, further reducing the pressure and temperature of the refrigerant, so that the mixed working medium becomes a pure liquid state after throttling by the second throttling device 8, and is ready for heat exchange in the evaporator 9. The non-azeotropic mixed working medium then passes through the second throttling device 8 and flows into the evaporator 9 along the connecting pipeline; the liquid working medium absorbs heat in the evaporator 9, then flows out of the outlet of the evaporator 9 and is transmitted to the compressor 1 through the return air port of the compressor 1. At the same time, after flowing out of the outlet of the first heat exchange channel 61, the mixed working medium is also transmitted through the connecting pipeline to the third throttling device 7 for throttling. The throttled mixed working medium is then transmitted to the second heat exchange channel 62 of the heat exchanger 6, where it flows into the heat exchanger 6 and cools the mixed working medium coming out of the liquid reservoir 4; the mixed working medium then flows out of the second heat exchange channel 62 and is transmitted to the compressor 1 through the air supply port of the compressor 1.

[0079] In one embodiment, the first throttling device 3, the second throttling device 8, and the third throttling device 7 are all expansion valves. The first throttling device 3, the second throttling device 8, and the third throttling device 7 are electrically connected to a controller, respectively, which controls the start and stop of the first throttling device 3, the second throttling device 8, and the third throttling device 7, and controls the opening of the first throttling device 3, the second throttling device 8, and the third throttling device 7 according to the operating requirements of different working conditions to control the flow rate of the refrigerant.

[0080] In one embodiment, a gas-liquid separator 14 is further provided on the refrigerant circulation loop, the inlet of the gas-liquid separator 14 is respectively connected to the outlet of the second heat exchange channel 62 and the outlet of the evaporator 9, and the outlet of the gas-liquid separator 14 is connected to the return air port of the compressor 1.

[0081] In this embodiment, the gas-liquid separator 14 can separate the liquid refrigerant from the non-azeotropic mixture returning from the heat exchanger 6 or evaporator 9, preventing the liquid from directly entering the compressor 1. Liquid refrigerant entering the compressor 1 may cause liquid hammer, which is a phenomenon in which the liquid is compressed within the compressor 1. Because the liquid is incompressible, it exerts a significant impact force on the components of the compressor 1, potentially damaging the valve plate, piston, and other components of the compressor 1. In severe cases, the compressor 1 may even be scrapped. Furthermore, by separating the gas and liquid, the flow rate of the gaseous refrigerant entering the compressor 1 becomes more stable and uniform, helping the compressor 1 to operate more efficiently and thus improving the performance and energy efficiency of the entire heat pump system.

[0082] In one embodiment, an evaporator fan 15 is further included, and the evaporator fan 15 is used to drive air to flow through the evaporator 9.

[0083] In this embodiment, the evaporator fan 15 is used to promote air flow, so that air flows continuously and evenly across the surface of the evaporator 9, accelerating heat transfer between the air and the evaporator 9. Moreover, by uniformly supplying air, the evaporator fan 15 helps maintain a uniform surface temperature on the evaporator 9, reducing the possibility of frosting or making frosting more uniform, thereby extending the effective operating time of the evaporator 9, reducing the frequency of defrosting, and improving the overall operating efficiency of the non-azeotropic mixture heat pump system.

[0084] On the other hand, Figure 5 As shown, the present invention also provides a control method for a non-azeotropic mixed working fluid heat pump system, which is applied to a non-azeotropic mixed working fluid heat pump system. The control method includes the following steps:

[0085] Step S100: Acquire the ambient temperature, compare the ambient temperature with the first target temperature and the second target temperature respectively, and the first target temperature is greater than the second target temperature;

[0086] Step S200: When the ambient temperature is greater than or equal to the first target temperature, control the electronically controlled valve group to operate so that the heat pump system operates in the first heat exchange mode;

[0087] Step S300: When the ambient temperature is less than or equal to the second target temperature, the electrically controlled valve group is controlled to operate so that the heat pump system operates in the second heat exchange mode.

[0088] In this embodiment, the non-azeotropic mixture heat pump system disclosed in the present invention can select different heat exchange modes according to the actual ambient temperature. When the ambient temperature is greater than or equal to the first target temperature, the heat pump system is operated in the first heat exchange mode by controlling the electronically controlled valve group; the refrigerant is caused to flow sequentially through the condenser 2, the first heat exchange channel 61, the second throttling device 8, the evaporator 9, the second heat exchange channel 62, and the return air port of the compressor 1. During the refrigerant circulation process, the evaporator 9 absorbs heat from the air, and combined with the work performed by the compressor 1, the two parts of energy are finally released in the condenser 2, causing the heat pump system to heat and raise the water temperature. In addition, during the process of transferring the non-azeotropic mixture from the outlet of the condenser 2 to the inlet of the evaporator 9, the mixture undergoes throttling and heat recovery once, which greatly reduces the throttling temperature difference between the condenser 2 and the evaporator 9 compared to traditional heat pump systems, and ultimately significantly reduces the throttling loss, thereby improving the heating performance of the non-azeotropic mixture heat pump system.

[0089] When the ambient temperature is less than or equal to the second target temperature, the heat pump system operates in the second heat exchange mode by controlling the electrically controlled valve group; the refrigerant is caused to flow sequentially through the condenser 2 and the first heat exchange channel 61, and after the refrigerant flows out of the outlet of the first heat exchange channel 61, it flows along the first circulation branch and the second circulation branch respectively; wherein, the refrigerant on the first circulation branch flows sequentially through the second throttling device 8, the evaporator 9 and the return air port of the compressor 1, and the refrigerant on the second circulation branch flows sequentially through the third throttling device 7, the second heat exchange channel 62 and the air supply port of the compressor 1. During the refrigerant circulation process, the mixed working fluid is throttled by the third throttling device 7 and flows into the second heat exchange channel 62 of the heat exchanger 6, and then flows into the air supply port of the compressor 1 to supply air to the compressor 1, thereby reducing the pressure ratio of the compressor 1 and thus reducing the exhaust temperature of the compressor 1, so that the heat pump system operates more stably and efficiently under low ambient temperatures. Furthermore, the refrigerant in the first circulation branch exchanges heat with the refrigerant in the second circulation branch in heat exchanger 6, thereby effectively reducing the temperature of the mixed refrigerant flowing out of the first heat exchange channel 61, causing the mixed refrigerant to be further supercooled before entering the evaporator 9, thereby effectively improving the heating effect of the heat pump system and meeting higher indoor heating needs under low ambient temperature conditions. By switching the non-azeotropic mixed refrigerant heat pump system between the first heat exchange mode and the second heat exchange mode, the heat pump system can effectively reduce its overall energy consumption while operating stably and meeting heating needs, thereby improving the user experience.

[0090] like Figure 6 As shown, in one embodiment, the following steps are also included:

[0091] Step S400: When the heat pump system operates in the first heat exchange mode, the first throttling device 3, the second throttling device 8, the third electrically controlled valve 11, and the fourth electrically controlled valve 10 are controlled to be in an open state, and the third throttling device 7, the first electrically controlled valve 12, and the second electrically controlled valve 13 are controlled to be in a closed state;

[0092] Step S500: When the heat pump system operates in the second heat exchange mode, the first throttling device 3, the second throttling device 8, the third throttling device 7, the first electrically controlled valve 12 and the second electrically controlled valve 13 are controlled to be in the open state, and the third electrically controlled valve 11 and the fourth electrically controlled valve 10 are controlled to be in the closed state.

[0093] In this embodiment, when the heat pump system operates in the first heat exchange mode, the first throttling device 3, the second throttling device 8, the third electrically controlled valve 11 and the fourth electrically controlled valve 10 are controlled to be in the open state, and the third throttling device 7, the first electrically controlled valve 12 and the second electrically controlled valve 13 are controlled to be in the closed state; the refrigerant is discharged from the exhaust port of the compressor 1 and flows through the condenser 2, the first throttling device 3, the first heat exchange channel 61, the second throttling device 8, the evaporator 9, the second heat exchange channel 62 and the return air port of the compressor 1 in sequence. During the refrigerant circulation process, the evaporator 9 absorbs heat from the air, and combined with the work of the compressor 1, the two parts of energy are finally released in the condenser 2, so that the heat pump system heats and raises the water temperature. Moreover, in the process of the non-azeotropic mixed working fluid being transmitted from the outlet of the condenser 2 to the inlet of the evaporator 9, the mixed working fluid undergoes two stages of throttling and one heat recovery, which greatly reduces the throttling temperature difference from the condenser 2 to the evaporator 9 compared with the traditional heat pump system, and ultimately greatly reduces the throttling loss, thereby improving the heating performance of the non-azeotropic mixed working fluid heat pump system.

[0094] When the heat pump system operates in the second heat exchange mode, the first throttling device 3, the second throttling device 8, the third throttling device 7, the first electrically controlled valve 12 and the second electrically controlled valve 13 are controlled to be in the open state, and the third electrically controlled valve 11 and the fourth electrically controlled valve 10 are controlled to be in the closed state, so as to control the heat pump system to be in the second heat exchange mode. During the refrigerant circulation process, after the mixed working medium flows out of the first heat exchange channel 61, the mixed working medium continues to flow along the first circulation branch and the second circulation branch respectively. When the mixed working medium flows along the first circulation branch, the mixed working medium returns to the return air port of the compressor 1 after passing through the second throttling device 8, the evaporator 9 and the first electrically controlled valve 12. When the mixed working medium flows along the second circulation branch, the mixed working medium is throttled by the third throttling device 7 and flows into the second heat exchange channel 62 of the heat exchanger 6, and enters the air supply port of the compressor 1 through the second electrically controlled valve 13 to supply air to the compressor 1, thereby reducing the pressure ratio of the compressor 1 and reducing the exhaust temperature of the compressor 1, so that the heat pump system operates more stably and efficiently under low ambient temperature. The refrigerant in the first circulation branch and the refrigerant in the second circulation branch exchange heat in the heat exchanger 6; thereby effectively reducing the temperature of the mixed working fluid flowing out of the first heat exchange channel 61, so that the mixed working fluid is further supercooled before entering the evaporator 9, thereby effectively improving the heating effect of the heat pump system, and can meet the higher indoor heating demand under low ambient temperature conditions. According to the change in ambient temperature, the non-azeotropic mixed working fluid heat pump system is controlled to switch between the first heat exchange mode and the second heat exchange mode, so that the heat pump system can effectively reduce the overall energy consumption of the heat pump system while operating stably and meeting the heating demand, thereby improving the user experience. Among them, the first target temperature can be specifically -15℃, -14℃, -13℃, -12℃, -11℃, -10℃, etc., and the second target temperature can be specifically -20℃, -21℃, -22℃, -23℃, -24℃, -25℃, etc., which can be set according to actual usage needs.

[0095] In one of the embodiments, the further embodiment includes: when the ambient temperature is greater than the second target temperature and less than the first target temperature, controlling the heat pump system to operate in a current mode, the current mode including the first heat exchange mode and the second heat exchange mode.

[0096] In this embodiment, when the ambient temperature is greater than the second target temperature and less than the first target temperature, in order to avoid the heat pump system from frequently switching the heat exchange mode, the heat pump system can be kept running in the current mode. For example, when the ambient temperature is less than or equal to the second target temperature, the heat pump system is running in the second heat exchange mode for heating. As the ambient temperature rises, the ambient temperature is greater than the second target temperature but still less than the first target temperature. At this time, the heat pump system can be kept running in the second heat exchange mode. Similarly, when the ambient temperature is greater than or equal to the first target temperature, the heat pump system is running in the first heat exchange mode. As the ambient temperature decreases, the ambient temperature is less than the first target temperature but still greater than the second target temperature. At this time, the heat pump system is still kept running in the first heat exchange mode. Frequent switching of the heat exchange mode of the heat pump system due to the ambient temperature fluctuating near the target temperature can be avoided, thereby reducing the overall energy consumption of the system.

[0097] In one embodiment, Figure 7 As shown, the following steps are also included:

[0098] Step S700: comparing the ambient temperature with the third target temperature, where the third target temperature is lower than the second target temperature;

[0099] Step S800: When the ambient temperature is lower than the third target temperature, the first electrically controlled valve 12, the fifth electrically controlled valve 5, and the first throttling device 3 are controlled to be in an open state, and the first throttling device 3 is controlled to be opened to a maximum opening, and the second throttling device 8, the third throttling device 7, the second electrically controlled valve 13, the third electrically controlled valve 11, the fourth electrically controlled valve 10, and the evaporator fan 15 are controlled to be in a closed state;

[0100] Step S900: When the ambient temperature is greater than or equal to the third target temperature, the fifth electrically controlled valve 5, the third electrically controlled valve 11 and the fourth electrically controlled valve 10 are controlled to be in a closed state, and the first throttling device 3, the second throttling device 8, the third throttling device 7, the first electrically controlled valve 12, the second electrically controlled valve 13 and the evaporator fan 15 are controlled to be in an open state.

[0101] In this embodiment, after the heat pump system is turned on, the ambient temperature and the inlet water temperature of the condenser 2 are first obtained, and the initial openings of the first throttling device 3 and the second throttling device 8 are determined based on the ambient temperature and the inlet water temperature. For example, when the ambient temperature and / or the inlet water temperature are high, the initial openings of the first throttling device 3 and the second throttling device 8 are relatively small.

[0102] The ambient temperature is further compared with a third target temperature, which can be set based on actual needs. If the ambient temperature is lower than the third target temperature, it indicates that the ambient temperature is low and frost has formed on the surface of the evaporator 9. At this point, the fifth electrically controlled valve 5 on the pipeline between the reservoir 4 and the evaporator 9 is controlled to open, thereby connecting the reservoir 4 and the evaporator 9. The second throttling device 8, the third throttling device 7, the second electrically controlled valve 13, the third electrically controlled valve 11, the fourth electrically controlled valve 10, and the evaporator fan 15 are controlled to be closed, switching the heat pump system to defrost mode. At this point, most of the gaseous refrigerant in the reservoir 4 enters the bypass line 41 from the second refrigerant outlet 44 and is transported to the evaporator 9 for defrosting. It is then drawn into the compressor 1 and continues to circulate through the compressor 1. As the gaseous refrigerant condenses in the evaporator 9, it releases a large amount of heat, which contributes to the defrosting process. Simultaneously, the first throttling device 3 is controlled to open to its maximum opening, allowing more refrigerant to evaporate and absorb heat within the evaporator 9, thereby increasing the temperature of the evaporator 9 and accelerating the melting of the frost layer.

[0103] When the ambient temperature is greater than or equal to the third target temperature, it indicates that the ambient temperature is in a normal state; the first throttling device 3, the second throttling device 8, the third throttling device 7, the first electrically controlled valve 12, the second electrically controlled valve 13 and the evaporator fan 15 are in an open state, and the fifth electrically controlled valve 5, the third electrically controlled valve 11 and the fourth electrically controlled valve 10 are in a closed state, so as to prevent the gaseous working medium from flowing directly from the liquid reservoir 4 into the evaporator 9, so that the non-azeotropic mixed working medium heat pump system can operate in the second heat exchange mode.

[0104] In one embodiment, Figure 8 As shown, it also includes:

[0105] Step S810: In response to the heat pump system being in the defrost mode, detecting the outlet temperature of the evaporator 9 and comparing the outlet temperature of the evaporator 9 with a fourth target temperature;

[0106] Step S820: When the outlet temperature of the evaporator 9 is greater than or equal to the fourth target temperature, the evaporator fan 15, the first throttling device 3, the second throttling device 8, the third throttling device 7, the first electrically controlled valve 12, and the second electrically controlled valve 13 are controlled to be open, and the fifth electrically controlled valve 5, the third electrically controlled valve 11, and the fourth electrically controlled valve 10 are controlled to be closed, so as to switch to the second heat exchange mode;

[0107] Step S830: When the outlet temperature of the evaporator 9 is lower than the fourth target temperature, the evaporator fan 15, the second throttling device 8, the third throttling device 7, the second electrically controlled valve 13, the third electrically controlled valve 11 and the fourth electrically controlled valve 10 are controlled to be in a closed state, and the first electrically controlled valve 12, the fifth electrically controlled valve 5 and the first throttling device 3 are controlled to be in an open state to maintain the defrost mode.

[0108] In this embodiment, when the operating mode of the non-azeotropic mixture heat pump system is switched to the defrost mode, the outlet temperature of the evaporator 9 is continuously detected by a temperature sensor and compared with a fourth target temperature, wherein the fourth target temperature can be set according to actual needs. When the outlet temperature of the evaporator 9 is greater than or equal to the fourth target temperature, it indicates that the operating condition of the non-azeotropic mixture heat pump system has returned to normal. At this time, the evaporator fan 15, the first throttling device 3, the second throttling device 8, the third throttling device 7, the first electric control valve 12, and the second electric control valve 13 are controlled to open, so that the heating circuit of the non-azeotropic mixture heat pump system returns to normal operating state. At the same time, the fifth electric control valve 5, the third electric control valve 11, and the fourth electric control valve 10 are controlled to close, so that the operating mode of the non-azeotropic mixture heat pump system is switched to the second heat exchange mode. It can be understood that the opening degrees of the first throttling device 3, the second throttling device 8, and the third throttling device 7 are all restored to the opening degrees before defrosting.

[0109] When the outlet temperature of the evaporator 9 is lower than the fourth target temperature, it means that the frost layer on the surface of the evaporator 9 has not been completely removed; at this time, the evaporator fan 15, the second throttling device 8, the third throttling device 7, the second electric control valve 13, the third electric control valve 11 and the fourth electric control valve 10 are still maintained in the closed state, and the first electric control valve 12, the fifth electric control valve 5 and the first throttling device 3 are still maintained in the open state to maintain the defrost mode until the frost layer on the surface of the evaporator 9 is completely removed.

[0110] Figure 9 The schematic structural diagram of an embodiment of a non-azeotropic mixed working fluid heat pump system provided by an embodiment of the present invention is shown. The specific embodiment of the present invention does not limit the specific implementation of the non-azeotropic mixed working fluid heat pump system.

[0111] like Figure 9 As shown, the heat pump may include: a processor 502 , a communications interface 504 , a memory 506 , and a communication bus 508 .

[0112] Processor 502, communication interface 504, and memory 506 communicate with each other via communication bus 508. Communication interface 504 is used to communicate with other devices, such as client devices or other server network elements. Processor 502 is used to execute program 510, which may specifically perform the steps of the aforementioned embodiment of the control method for a non-azeotropic mixed working fluid heat pump system.

[0113] Specifically, the program 510 may include program code including computer-executable instructions.

[0114] Processor 502 may be a central processing unit (CPU), an application-specific integrated circuit (ASIC), or one or more integrated circuits configured to implement embodiments of the present invention. The one or more processors included in the non-azeotropic mixture heat pump system may be processors of the same type, such as one or more CPUs, or may be processors of different types, such as one or more CPUs and one or more ASICs.

[0115] The memory 506 is used to store the program 510. The memory 506 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk storage.

[0116] The program 510 can be specifically called by the processor 502 to enable the non-azeotropic mixed working fluid heat pump system to execute the relevant steps in the above-mentioned control method embodiment for the non-azeotropic mixed working fluid heat pump system.

[0117] It can be understood by those skilled in the art that Figure 9 The structure shown is only for illustration and does not limit the structure of the above-mentioned equipment. For example, the non-azeotropic mixed working fluid heat pump system may also include Figure 9 More or fewer components than shown, or with Figure 9 Different configurations shown.

[0118] The embodiment of the present invention also provides a computer-readable storage medium. The above-mentioned method according to the embodiment of the present invention can be implemented in hardware, firmware, or implemented as a computer code that can be recorded in a storage medium, or implemented as a computer code that is originally stored in a remote storage medium or a non-temporary machine-readable storage medium and downloaded through a network and will be stored in a local storage medium, so that the method described herein can be stored in such software processing on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only storage memory, a random access memory, a flash memory, a hard disk or a solid-state drive, etc.; further, the storage medium can also include a combination of the above-mentioned types of memory. It can be understood that a computer, a processor, a microprocessor controller or programmable hardware includes a storage component that can store or receive software or computer code. When the software or computer code is accessed and executed by a computer, a processor or hardware, the method shown in the above embodiment is implemented.

[0119] In the specific contents of the above-mentioned specific implementation methods, the various technical features can be combined in any non-contradictory manner. In order to make the description concise, not all possible combinations of the above-mentioned technical features are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0120] The specific contents of the above-mentioned specific embodiments merely represent several embodiments of the present invention. While the description is relatively specific and detailed, it should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art may make various modifications and improvements without departing from the scope of the present invention, and these modifications and improvements fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be based on the appended claims.

Claims

1. A non-azeotropic mixed working fluid heat pump system, characterized in that: include: A refrigerant circulation loop connected to the exhaust port of the compressor (1) and the return port of the compressor (1) to form a loop, wherein the refrigerant circulation loop is provided with a condenser (2), a heat exchanger (6), a second throttling device (8) and an evaporator (9) in sequence along the refrigerant flow direction; The heat exchanger (6) has a first heat exchange channel (61) and a second heat exchange channel (62) for exchanging heat with each other, the first heat exchange channel (61) being connected between the outlet of the condenser (2) and the inlet of the evaporator (9), and the second heat exchange channel (62) being connected between the outlet of the evaporator (9) and the return air port of the compressor (1); The heat pump system further comprises a third throttling device (7), wherein the third throttling device (7) is connected between the outlet of the first heat exchange channel (61) and the inlet of the second heat exchange channel (62); The heat pump system includes an electrically controlled valve group, which is used to control the heat pump system to operate in a first heat exchange mode or a second heat exchange mode; In the first heat exchange mode, the refrigerant flows sequentially through the condenser (2), the first heat exchange channel (61), the second throttling device (8), the evaporator (9), the second heat exchange channel (62), and the return air port of the compressor (1); In the second heat exchange mode, the refrigerant flows through the condenser (2) and the first heat exchange channel (61) in sequence. After the refrigerant flows out from the outlet of the first heat exchange channel (61), it flows along the first circulation branch and the second circulation branch respectively. The refrigerant on the first circulation branch flows through the second throttling device (8), the evaporator (9), and the return air port of the compressor (1) in sequence. The refrigerant on the second circulation branch flows through the third throttling device (7), the second heat exchange channel (62), and the air supply port of the compressor (1) in sequence. Also includes: a first throttling device (3), the first throttling device (3) being connected between the outlet of the condenser (2) and the inlet of the first heat exchange channel (61); and a second throttling device (8) being connected between the outlet of the first heat exchange channel (61) and the inlet of the evaporator (9); A liquid reservoir (4), wherein the liquid reservoir (4) is provided with a refrigerant inlet (42), a first refrigerant outlet (43) and a second refrigerant outlet (44), wherein the refrigerant inlet (42) is connected to the first throttling device (3), the first refrigerant outlet (43) is connected to the inlet of the first heat exchange channel (61), and the second refrigerant outlet (44) is connected to the inlet of the evaporator (9) through a bypass line (41), and a fifth electric control valve (5) is provided on the bypass line (41).

2. The non-azeotropic mixed working fluid heat pump system according to claim 1, characterized in that: The electrically controlled valve group comprises a first electrically controlled valve (12), a second electrically controlled valve (13) and a fourth electrically controlled valve (10), wherein the first electrically controlled valve (12) is arranged between the outlet of the evaporator (9) and the return air port of the compressor (1); the second electrically controlled valve (13) is arranged between the outlet of the second heat exchange channel (62) and the air supply port of the compressor (1); and the fourth electrically controlled valve (10) is arranged between the outlet of the second heat exchange channel (62) and the return air port of the compressor (1).

3. The non-azeotropic mixed working fluid heat pump system according to claim 1, characterized in that: The electrically controlled valve group further comprises a third electrically controlled valve (11), wherein the third electrically controlled valve (11) is connected between the outlet of the evaporator (9) and the inlet of the second heat exchange channel (62).

4. The non-azeotropic mixed working fluid heat pump system according to claim 1, characterized in that: The first throttling device (3), the second throttling device (8) and the third throttling device (7) are all expansion valves.

5. The non-azeotropic mixed working fluid heat pump system according to any one of claims 1 to 4, characterized in that: The refrigerant circulation loop is further provided with a gas-liquid separator (14), the inlet of the gas-liquid separator (14) being connected to the outlet of the second heat exchange channel (62) and the outlet of the evaporator (9), respectively, and the outlet of the gas-liquid separator (14) being connected to the return air port of the compressor (1).

6. The non-azeotropic mixed working fluid heat pump system according to any one of claims 1 to 4, characterized in that: It also includes an evaporator fan (15), which is used to drive air to flow through the evaporator (9).

7. A control method for a non-azeotropic mixed working fluid heat pump system, applied to the non-azeotropic mixed working fluid heat pump system according to any one of claims 1 to 6, characterized in that: The control method includes: Acquiring an ambient temperature, and comparing the ambient temperature with a first target temperature and a second target temperature, respectively, wherein the first target temperature is greater than the second target temperature; When the ambient temperature is greater than or equal to the first target temperature, controlling the electrically controlled valve group to operate so that the heat pump system operates in the first heat exchange mode; When the ambient temperature is less than or equal to the second target temperature, the electrically controlled valve group is controlled to operate so that the heat pump system operates in the second heat exchange mode.

8. The control method of the non-azeotropic mixed working fluid heat pump system according to claim 7, characterized in that: The electrically controlled valve group comprises a first electrically controlled valve (12), a second electrically controlled valve (13), a third electrically controlled valve (11) and a fourth electrically controlled valve (10), wherein the first electrically controlled valve (12) is arranged between the outlet of the evaporator (9) and the return air port of the compressor (1); the second electrically controlled valve (13) is arranged between the outlet of the second heat exchange channel (62) and the air supply port of the compressor (1); the third electrically controlled valve (11) is connected between the outlet of the evaporator (9) and the inlet of the second heat exchange channel (62); the fourth electrically controlled valve (10) is arranged between the outlet of the second heat exchange channel (62) and the return air port of the compressor (1); the heat pump system further comprises a first throttling device (3) connected between the outlet of the condenser (2) and the inlet of the first heat exchange channel (61); The method further comprises: When the heat pump system operates in the first heat exchange mode, the first throttling device (3), the second throttling device (8), the third electrically controlled valve (11) and the fourth electrically controlled valve (10) are controlled to be in an open state, and the third throttling device (7), the first electrically controlled valve (12) and the second electrically controlled valve (13) are controlled to be in a closed state; When the heat pump system operates in the second heat exchange mode, the first throttling device (3), the second throttling device (8), the third throttling device (7), the first electrically controlled valve (12) and the second electrically controlled valve (13) are controlled to be in an open state, and the third electrically controlled valve (11) and the fourth electrically controlled valve (10) are controlled to be in a closed state.

9. The control method of the non-azeotropic mixed working fluid heat pump system according to claim 8, characterized in that: The method further comprises: When the ambient temperature is greater than the second target temperature and less than the first target temperature, the heat pump system is controlled to operate in a current mode, where the current mode includes the first heat exchange mode and the second heat exchange mode.

10. The control method of the non-azeotropic mixed working fluid heat pump system according to claim 8, characterized in that: The heat pump system further includes a liquid reservoir (4) and an evaporator fan (15) for driving air to flow through the evaporator (9), the liquid reservoir (4) is provided with a refrigerant inlet (42), a first refrigerant outlet (43) and a second refrigerant outlet (44), the refrigerant inlet (42) is connected to the first throttling device (3), the first refrigerant outlet (43) is connected to the inlet of the first heat exchange channel (61), and the second refrigerant outlet (44) is connected to the inlet of the evaporator (9) through a bypass line (41), and a fifth electric control valve (5) is provided on the bypass line (41); The method further comprises: comparing the ambient temperature with a third target temperature, the third target temperature being lower than the second target temperature; When the ambient temperature is lower than the third target temperature, the first electrically controlled valve (12), the fifth electrically controlled valve (5) and the first throttling device (3) are controlled to be in an open state, and the first throttling device (3) is controlled to be opened to a maximum opening, and the second throttling device (8), the third throttling device (7), the second electrically controlled valve (13), the third electrically controlled valve (11), the fourth electrically controlled valve (10) and the evaporator fan (15) are controlled to be in a closed state; When the ambient temperature is greater than or equal to the third target temperature, the fifth electrically controlled valve (5), the third electrically controlled valve (11) and the fourth electrically controlled valve (10) are controlled to be in a closed state, and the first throttling device (3), the second throttling device (8), the third throttling device (7), the first electrically controlled valve (12), the second electrically controlled valve (13) and the evaporator fan (15) are controlled to be in an open state.

11. The control method of the non-azeotropic mixed working fluid heat pump system according to claim 10, characterized in that: The method further comprises: In response to the heat pump system being in a defrost mode, detecting the outlet temperature of the evaporator (9), and comparing the outlet temperature of the evaporator (9) with a fourth target temperature; When the outlet temperature of the evaporator (9) is greater than or equal to the fourth target temperature, the evaporator fan (15), the first throttling device (3), the second throttling device (8), the third throttling device (7), the first electric control valve (12) and the second electric control valve (13) are controlled to be open, and the fifth electric control valve (5), the third electric control valve (11) and the fourth electric control valve (10) are controlled to be closed, so as to switch to the second heat exchange mode; When the outlet temperature of the evaporator (9) is lower than the fourth target temperature, the evaporator fan (15), the second throttling device (8), the third throttling device (7), the second electric control valve (13), the third electric control valve (11) and the fourth electric control valve (10) are controlled to be in a closed state, and the first electric control valve (12), the fifth electric control valve (5) and the first throttling device (3) are controlled to be in an open state to maintain the defrosting mode.

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