Refrigerant pump air conditioner and its control method

Abstract

This application provides a refrigerant pump air conditioner and its control method. The refrigerant pump air conditioner includes a first circulation component and a heat exchanger. The first circulation component includes a refrigerant pump, a liquid receiver, a regenerator, and an evaporator. An input pipeline connects the output end of the refrigerant pump to the input end of the evaporator. The output end of the evaporator is connected to the first input end of the regenerator. The first output end of the regenerator is connected to the first input end of the heat exchanger. The first output end of the heat exchanger is connected to the output end of the liquid receiver. The output end of the liquid receiver is connected to the input end of the refrigerant pump. A bypass pipeline connects the output end of the refrigerant pump to the second input end of the regenerator. The second output end of the regenerator is connected to the input pipeline. A bypass control valve is installed on the bypass pipeline. When the load suddenly increases, the bypass control valve can be opened to send a portion of the low-temperature first heat exchange medium into the regenerator to pre-cool the high-temperature first heat exchange medium, increase the subcooling value before the refrigerant pump, and avoid refrigerant pump cavitation and shutdown problems.

Description

Technical Field

[0001] This application belongs to the field of refrigerant pump air conditioning technology, and more specifically, relates to a refrigerant pump air conditioner and its control method. Background Technology

[0002] A refrigerant pump air conditioner is an air conditioning system that uses Freon as the working medium. Driven by a refrigerant pump, the Freon circulates within the system, achieving cooling or heating. Compared to traditional compressor-driven air conditioning systems, refrigerant pump air conditioners have a higher energy efficiency ratio and lower noise levels, making them particularly suitable for locations requiring low-noise operation, such as hospitals and libraries.

[0003] When the terminal load of a refrigerant pump air conditioner suddenly increases in a short period of time, the compressor in the refrigerant pump air conditioner will run at full load. If the subcooling value of the heat exchange medium upstream of the refrigerant pump is still low at this time, since there are no other effective means in the system to quickly increase the subcooling value of the heat exchange medium, and the temperature control regulation of the entire system has a certain lag, in order to avoid cavitation problems in the refrigerant pump, the refrigerant pump air conditioner can only be shut down and alarmed, which will cause the terminal temperature to continue to rise and will also affect the normal operation of other temperature control devices. Summary of the Invention

[0004] The purpose of this application is to provide a refrigerant pump air conditioner and its control method to solve the problem of shutdown caused by low subcooling value before the pump when the terminal load suddenly increases in the prior art.

[0005] To achieve the above objectives, in a first aspect, this application provides a refrigerant pump air conditioner, including a first circulation assembly and a heat exchanger; the first circulation assembly includes an evaporator, a refrigerant pump, and a regenerator, the regenerator having a first regenerator channel and a second regenerator channel capable of exchanging heat with each other, an input pipe connecting the output end of the refrigerant pump to the input end of the evaporator, an output pipe connecting the output end of the evaporator to the input end of the first regenerator channel, the heat exchanger having a first heat exchange channel, the output end of the first regenerator channel connecting to the input end of the first heat exchange channel, and the output end of the first heat exchange channel connecting to the input end of the refrigerant pump; a bypass pipe connecting the output end of the refrigerant pump to the input end of the second regenerator channel, the output end of the second regenerator channel connecting to the input pipe, and a bypass control valve connected to the bypass pipe.

[0006] In some embodiments of the first aspect, the first circulation component further includes a pressure sensor and a temperature sensor, both of which are located upstream of the fluorine pump and are used to acquire the pump inlet pressure value and pump inlet temperature value of the fluorine pump, respectively.

[0007] In some embodiments of the first aspect, the first circulation assembly further includes a one-way valve and a storage tank, the one-way valve being connected between the output end of the second regenerative channel and the output pipeline; the output end of the first heat exchange channel being connected to the output end of the storage tank, and the output end of the storage tank being connected to the input end of the fluorine pump.

[0008] In some embodiments of the first aspect, the refrigerant pump air conditioner further includes a second circulation assembly, which includes a compressor, a first condenser, and a throttling device. The output end of the compressor is connected to the input end of the first condenser, the output end of the first condenser is connected to the input end of the throttling device, and the heat exchanger further has a second heat exchange channel that exchanges heat with the first heat exchange channel. The output end of the throttling device is connected to the input end of the second heat exchange channel, and the output end of the second heat exchange channel is connected to the input end of the compressor.

[0009] In some embodiments of the first aspect, the first circulation assembly further includes a second condenser, which is arranged side-by-side with the first condenser and located upstream of the first condenser; a first branch pipe is connected between the output pipe and the input end of the second condenser, and a first control valve is provided on the first branch pipe; the output end of the second condenser is connected to the first input end of the regenerator; a second branch pipe is connected between the output pipe and the input end of the first regenerator channel, and a second control valve is provided on the second branch pipe.

[0010] In some embodiments of the first aspect, a liquid ball valve is provided on the side of the input pipeline near the evaporator; and a gas ball valve is provided on the side of the output pipeline near the evaporator.

[0011] Secondly, this application provides a control method for a refrigerant pump air conditioner. The refrigerant pump air conditioner includes a first circulation component and a heat exchanger. The first circulation component includes a refrigerant pump and a regenerator. The input end of the refrigerant pump is connected to the output end of a first regenerating channel of the regenerator. The output end of the refrigerant pump is connected to the input end of a second regenerating channel of the regenerator via a bypass pipe. A bypass control valve is provided on the bypass pipe. The heat exchanger has a first heat exchange channel. The output end of the first regenerating channel is connected to the input end of the first heat exchange channel, and the output end of the first heat exchange channel is connected to the input end of the refrigerant pump. The control method includes:

[0012] The pre-pump subcooling value of the fluorine pump is obtained in real time;

[0013] When the subcooling value before the pump is less than or equal to the subcooling determination value, the bypass control valve is opened.

[0014] In some embodiments of the second aspect, the refrigerant pump air conditioner further includes a second circulation assembly, wherein the first circulation assembly and the second circulation assembly exchange heat through the heat exchanger, and the second circulation assembly includes a compressor;

[0015] The control method further includes: when the subcooling value before the pump is less than or equal to the subcooling judgment value and the bypass control valve is in the open state, unlocking the operating frequency limit of the compressor and increasing the operating frequency of the compressor.

[0016] In some embodiments of the second aspect, the control method further includes:

[0017] When the subcooling value before the pump is greater than the subcooling protection stop value, the operating frequency of the compressor is reduced, and the maximum operating frequency of the compressor is limited to a locked frequency; the subcooling protection stop value is greater than the subcooling determination value.

[0018] In some embodiments of the second aspect, the control method further includes:

[0019] When the subcooling value before the pump exceeds the subcooling protection stop value, the bypass control valve is closed.

[0020] The beneficial effects of the refrigerant pump air conditioner and its control method provided in this application are as follows: During normal operation, the refrigerant pump sends the first heat exchange medium, which is in a low-temperature state in the storage tank, into the evaporator through the input pipeline. The evaporator exchanges heat with the room to achieve the purpose of cooling the room. After the first heat exchange medium is heated by heat exchange in the evaporator, it is sent into the heat exchanger through the output pipeline. The heat exchanger cools the first heat exchange medium to a low-temperature state, and the first heat exchange medium in the low-temperature state flows back into the storage tank. This application adds a regenerator before the heat exchanger and a bypass line to the regenerator after the refrigerant pump. When the subcooling value before the refrigerant pump is low, the bypass control valve of the bypass line can be opened, allowing some of the low-temperature first heat exchange medium to flow into the regenerator before entering the evaporator. In the regenerator, it exchanges heat with the high-temperature first heat exchange medium output from the evaporator, pre-cooling the high-temperature first heat exchange medium. This increases the subcooling value before the refrigerant pump, making it less likely for the first heat exchange medium to generate flash gas and cause cavitation in the refrigerant pump. Furthermore, by pre-cooling the first heat exchange medium, the temperature of the first heat exchange medium at the evaporator inlet is lower, resulting in a lower evaporation temperature in the evaporator, improving the heat exchange effect of the evaporator, ensuring the evaporator's cooling effect on the room, and improving the stability of indoor temperature control. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the structure of a refrigerant pump air conditioner in an exemplary embodiment of this application;

[0023] Figure 2 This is a flowchart of a refrigerant pump air conditioning control method in an exemplary embodiment of this application;

[0024] Figure 3 This is a logic diagram of the control method for a refrigerant pump air conditioner in an exemplary embodiment of this application.

[0025] The following are the labeling elements in the figure:

[0026] 1-Fluorine pump; 11-Inlet line; 111-Liquid line ball valve; 12-Bypass line; 121-Bypass control valve; 13-Pressure sensor; 14-Temperature sensor; 2-Regenerator; 21-Check valve; 3-Storage tank; 4-Heat exchanger; 5-Evaporator; 51-Outlet line; 511-Gas line ball valve; 52-First branch line; 521-First control valve; 53-Second branch line; 531-Second control valve; 6-Compressor; 7-Expansion valve; 8-First condenser; 9-Second condenser. Detailed Implementation

[0027] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0028] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0029] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0030] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0031] Firstly, this application provides a refrigerant pump air conditioner, referring to... Figure 1 The refrigerant pump air conditioner includes a first circulation assembly and a heat exchanger 4. The first circulation assembly includes a refrigerant pump 1, a liquid storage tank 3, a regenerator 2, and an evaporator 5. The regenerator 2 has a first regenerating channel and a second regenerating channel capable of exchanging heat with each other. An input pipe 11 connects the output end of the refrigerant pump 1 to the input end of the evaporator 5. An output pipe 51 connects the output end of the evaporator 5 to the input end of the first regenerating channel. The heat exchanger 4 has a first regenerating channel. The output end of the first regenerating channel is connected to the input end of the first regenerating channel. The output end of the first regenerating channel is connected to the input end of the liquid storage tank 3. The output end of the liquid storage tank 3 is connected to the input end of the refrigerant pump 1. A bypass pipe 12 connects the output end of the refrigerant pump 1 to the input end of the second regenerating channel. The second output end of the second regenerating channel is connected to the input pipe 11, and a bypass control valve 121 is connected to the bypass pipe 12. The first heat exchange medium can be refrigerant (Freon).

[0032] Specifically, the refrigerant pump 1 is used to draw in the first heat exchange medium from its inlet and then output it at a certain pressure from its outlet, allowing the first heat exchange medium to overcome system resistance and circulate among the components. The storage tank 3 is used to store the first heat exchange medium at low temperatures. The outlet of the storage tank 3 can be connected to the inlet of the refrigerant pump 1 via a pipe fitting. The refrigerant pump 1 can extract a corresponding amount of the first heat exchange medium from the storage tank 3 according to pressure requirements. The outlet of the refrigerant pump 1 is connected to the inlet of the evaporator 5 via a pipe fitting, allowing the refrigerant pump 1 to deliver the first heat exchange medium into the evaporator 5 to dissipate heat and cool the room.

[0033] The inlet pipe 11, outlet pipe 51, and bypass pipe 12 are all fluid transport components consisting of one or more connected transport pipes. The output end of the refrigerant pump 1 can be connected to a tee fitting, and the same side of the inlet pipe 11 and bypass pipe 12 are connected in parallel to the output end of the refrigerant pump 1 via a tee fitting. The bypass control valve 121 can be connected between two transport pipes in the bypass pipe 12 to control the on / off state of the bypass pipe 12.

[0034] The regenerator 2 has a first regenerating channel for the flow of the first heat exchange medium after heat absorption and heating, and a second regenerating channel for the flow of the first heat exchange medium at a low temperature. The second regenerating channel can spirally surround the periphery of the first regenerating channel to increase the contact area between the first and second regenerating channels, so that the high-temperature first heat exchange medium and the low-temperature heat exchange medium can exchange heat with each other.

[0035] Evaporator 5 is installed indoors to lower the indoor temperature by absorbing indoor heat. The output of evaporator 5 is connected to the input of the first regenerative channel via output pipe 51, allowing the first heat exchange medium output from evaporator 5 to flow into the first regenerative channel of regenerator 2. A bypass pipe 12, on the side facing away from refrigerant pump 1, is connected to the input of the second regenerative channel. When bypass control valve 121 is open, the first heat exchange medium can flow into the second regenerative channel of regenerator 2 through bypass pipe 12. The output of the second regenerative channel can be connected to input pipe 11 via a fitting. For example, a tee fitting is provided on the side of input pipe 11 near evaporator 5, and the output of the second regenerative channel is connected to the tee fitting via the fitting, allowing the first heat exchange medium to flow from the output of the second regenerative channel into the first input pipe 11 and then be transported to evaporator 5 via input pipe 11.

[0036] Heat exchanger 4 is used to transfer and exchange heat. Heat exchanger 4 has a first heat exchange channel for the flow of a first heat exchange medium at a high temperature. The inlet end of the first heat exchange channel is connected to the outlet end of a second regenerative channel through a pipe fitting, so that the first heat exchange medium can flow into heat exchanger 4 from the outlet end of the second regenerative channel. The outlet end of the first heat exchange channel is connected to the inlet end of storage tank 3 through a pipe fitting, so that the first heat exchange medium can flow into storage tank 3 from the outlet end of the first heat exchange channel.

[0037] During normal operation, the bypass control valve 121 is closed. The first heat exchange medium in the storage tank 3 is transported to the evaporator 5 through the input pipeline 11 by the refrigerant pump 1. The evaporator 5 exchanges heat with the room to achieve the purpose of cooling the room. After being heated by heat exchange, the first heat exchange medium enters the heat exchanger 4 through the first regeneration channel of the regenerator 2 via the output pipeline 51. In the heat exchanger 4, it exchanges heat with other heat exchange media to cool down the first heat exchange medium. The cooled first heat exchange medium flows back into the storage tank 3 for storage, thus realizing the circulation of the first heat exchange medium among the storage tank 3, refrigerant pump 1, evaporator 5, and heat exchanger 4.

[0038] When the subcooling value before the pump is low, the bypass control valve 121 can be opened to connect the bypass pipe 12 to the regenerator 2. A portion of the first heat exchange medium output from the refrigerant pump 1 will flow into the second regenerating channel of the regenerator 2 through the bypass pipe 12. This allows the low-temperature first heat exchange medium to exchange heat with the heated first heat exchange medium in the first regenerating channel, thus pre-cooling the first heat exchange medium before it enters the heat exchanger 4. This improves the cooling effect of the heat exchanger 4 on the first heat exchange medium, thereby increasing the subcooling value before the refrigerant pump 1. The first heat exchange medium output from the output end of the second regenerating channel will flow into the input pipe 11 and enter the evaporator 5 to participate in heat dissipation and cooling.

[0039] By setting up a regenerator 2, when the subcooling value before the pump is low, a portion of the low-temperature first heat exchange medium is input into the second regenerating channel of the regenerator 2 to exchange heat with the first heat exchange medium, which is in a high-temperature state, output from the evaporator 5. This increases the subcooling value before the pump, ensuring a high subcooling value before the pump even when the load on the evaporator 5 side suddenly increases. This makes it less likely for the first heat exchange medium to generate flash gas, which could lead to cavitation of the refrigerant pump. In addition, by pre-cooling the first heat exchange medium, the temperature of the first heat exchange medium at the evaporator inlet is lower, resulting in a lower evaporation temperature in the evaporator. This improves the heat exchange effect of the evaporator, enhances the stability of indoor temperature control, and avoids shutdown problems.

[0040] In some embodiments, the bypass control valve 121 may be a solenoid valve, and the refrigerant pump air conditioner may also include a controller, which may be a host computer. The solenoid valve is connected to the host computer to transmit communication signals. When the subcooling value before the pump is lower than a preset value, the controller controls the bypass control valve 121 to open automatically, and when the subcooling value before the pump is higher than the preset value, the controller controls the bypass control valve 121 to close automatically.

[0041] In some embodiments, the first circulation assembly further includes a pressure sensor 13 and a temperature sensor 14, both of which are located upstream of the refrigerant pump 1. Specifically, the pressure sensor 13 and temperature sensor 14 can be located between the refrigerant pump 1 and the storage tank 3. The pressure sensor 13 is used to acquire the inlet pressure value of the refrigerant pump 1, and the temperature sensor 14 is used to acquire the inlet temperature value of the refrigerant pump 1, so as to calculate the inlet subcooling value of the refrigerant pump 1 using the inlet pressure value and the inlet temperature value. The inlet subcooling value can be calculated according to the calculation method of the prior art. In addition, the pressure sensor 13 and the temperature sensor can also be connected to the controller of the refrigerant pump air conditioner. After acquiring the inlet pressure value and the inlet temperature value, the controller generates the inlet subcooling value and controls the bypass control valve according to the magnitude of the inlet subcooling value.

[0042] In some embodiments, the first circulation assembly further includes a one-way valve 21, which is connected between the output end of the second regenerating channel and the output pipe 51. The one-way valve 21 is used to restrict the flow of the first heat exchange medium from the output pipe 51 to the regenerator 2. This prevents the first heat exchange medium in the output pipe 51 from flowing back from the output end of the second regenerating channel into the bypass pipe 12, ensuring a stable flow of the first heat exchange medium into the evaporator 5.

[0043] In some embodiments, the refrigerant pump air conditioner further includes a second circulation assembly, which includes a compressor 6, a first condenser 8, and a throttling device. The output end of the compressor 6 is connected to the input end of the first condenser 8, the output end of the first condenser 8 is connected to the input end of the throttling device, the output end of the throttling device is connected to the input end of a second heat exchange channel, and the output end of the second heat exchange channel is connected to the input end of the compressor 6, so that the second heat exchange medium circulates among the compressor 6, the first condenser 8, the throttling device, and the heat exchanger 4. The second heat exchange medium may also be refrigerant (Freon).

[0044] Specifically, the heat exchanger 4 also has a second heat exchange channel for the flow of the second heat exchange medium. The flow directions of the first heat exchange medium and the second heat exchange medium in the heat exchange device can be opposite to increase the heat exchange efficiency of the first heat exchange medium and the second heat exchange medium. For example, the first input end and the second output end are located on the lower side of the heat exchange device, and the first output end and the second input end are located on the upper side of the heat exchange device.

[0045] Compressor 6 drives the second heat exchange medium to flow under a certain pressure. The input end of compressor 6 is connected to the output end of the second heat exchange channel of the heat exchanger via pipe fittings. The first condenser 8 is a heat exchange device that can achieve steam condensation by reducing the steam temperature. The output end of compressor 6 is connected to the input end of first condenser 8 via pipe fittings, allowing the second heat exchange medium to enter the first condenser 8 under the delivery of compressor 6, and the first condenser 8 condenses and cools the first heat exchange medium.

[0046] The throttling device is used to regulate the pressure of the second heat exchange medium, thereby cooling it by pressurizing it. For example, the throttling device is an expansion valve 7. The input end of the expansion valve 7 is connected to the output end of the first condenser 8 via a pipe, allowing the second heat exchange medium to flow into the expansion valve 7. The output end of the expansion valve 7 is connected to the input end of the second heat exchange channel of the heat exchanger via a pipe, allowing the second heat exchange medium to re-enter the second heat exchange channel of the heat exchanger 4 after being pressurized and cooled by the expansion valve 7.

[0047] When compressor 6 is working, it drives the second heat exchange medium to circulate between the first condenser 8, expansion valve 7, and heat exchanger 4. After being cooled by the first condenser 8 and expansion valve 7, the second heat exchange medium, which is at a low temperature, exchanges heat with the first heat exchange medium, which is at a high temperature, in heat exchanger 4, thereby cooling the first heat exchange medium. After absorbing heat and heating up, the second heat exchange medium flows out from the output end of the second heat exchange channel and is then transported back into the first condenser 8 by compressor 6. The first condenser 8 performs preliminary cooling of the second heat exchange medium, which is at a high temperature. After preliminary cooling, the second heat exchange medium passes through expansion valve 7 again, where it is pressurized and cooled to a low temperature.

[0048] In some embodiments, the first circulation assembly further includes a second condenser 9, which is arranged side-by-side with the first condenser 8 and located upstream of the first condenser 8. This allows the first condenser 8 and the second condenser 9 to share a single fan unit, resulting in a more compact structure and lower cost. A first branch pipe 52 connects the output pipe 51 to the input end of the second condenser 9, and a first control valve 521 is installed on the first branch pipe 52. The output end of the second condenser 9 is connected to the input end of the first regenerative channel. A second branch pipe 53 connects the output pipe 51 to the input end of the regenerator 2, and a second control valve 531 is installed on the second branch pipe 53.

[0049] Specifically, both the first branch pipe 52 and the second branch pipe 53 are fluid transport components composed of multiple connected transport pipes. A tee connector can be installed on the side of the output pipe 51 facing away from the evaporator 5. The first branch pipe 52 and the second branch pipe 53 are connected in parallel with the output pipe 51 via the tee connector. The first branch pipe 52 connects the output pipe 51 and the evaporator 5. When the first control valve 521 is open, the first heat exchange medium can flow into the second condenser 9 through the first branch pipe 52. The output end of the second condenser 9 can be connected to the second branch pipe 53 via a fitting to connect to the input end of the first regenerative channel, and then flow into the first regenerative channel of the regenerator 2 after passing through the second condenser 9. The second branch pipe 53 connects the output pipe 51 and the input end of the first regenerative channel. When the second control valve 531 is open, the first heat exchange medium can flow directly into the regenerator 2 through the second branch pipe 53. The second condenser 9 can be a natural cooling condenser.

[0050] When the load on the evaporator 5 side is low, the first control valve 521 can be opened and the second control valve 531 can be closed. Simultaneously, the compressor 6 can be shut off, allowing the heated first heat exchange medium to flow from the evaporator 5 into the second condenser 9. The second condenser 9 is used alone to cool the first heat exchange medium, thus achieving low-power operation. When the load on the evaporator 5 side is high, the first control valve 521 can be closed and the second control valve 531 can be opened. Simultaneously, the compressor 6 can be started, allowing the first heat exchange medium to flow directly from the evaporator 5 into the heat exchanger 4. The heat exchanger 4 is used alone to cool the first heat exchange medium.

[0051] Furthermore, when using heat exchanger 4 alone to cool the first heat exchange medium is ineffective, the compressor 6 can be started after opening the first control valve 521 and the second control valve 531. This allows the first heat exchange medium to pass sequentially through the second condenser 9 and the heat exchanger 4, with the second condenser 9 and the heat exchanger 4 working together to cool the first heat exchange medium. Additionally, when the second condenser 9 and the compressor 6 circuit work together, if the subcooling value before the refrigerant pump 1 is still low, a portion of the low-temperature first heat exchange medium can be introduced into the regenerator 2 by opening the bypass control valve 121. This pre-cools the first heat exchange medium before it enters the heat exchanger 4, increasing the subcooling value before the pump and lowering the evaporation temperature of the evaporator 5, thus meeting the requirements of the evaporator 5 under high load operation.

[0052] The opening or closing of the first control valve 521 and the second control valve 531 can be manually controlled by maintenance personnel, or can be automatically controlled by a solenoid valve and the controller in the refrigerant pump air conditioner according to the setting of the control program or the instructions of maintenance personnel.

[0053] In some embodiments, a liquid line ball valve 111 is provided on the side of the inlet pipe 11 near the evaporator 5. The liquid line ball valve 111 is used to regulate the refrigerant flow in the inlet pipe 11 to ensure that the evaporator 5 can perform heat exchange efficiently. The opening degree of the liquid line ball valve 111 can be adjusted manually or automatically according to the operating status and cooling demand of the refrigerant pump air conditioner.

[0054] In some embodiments, a gas pipe ball valve 511 is provided on the side of the output pipe 51 near the evaporator 5. The gas pipe ball valve 511 is used to regulate the pressure inside the evaporator 5. When the pressure inside the evaporator 5 is too high, the gas pipe ball valve 511 automatically opens to release some gas, thereby reducing the pressure; conversely, when the pressure inside the evaporator 5 is too low, the gas pipe ball valve 511 automatically closes to maintain the pressure inside the evaporator 5 within a reasonable range.

[0055] Secondly, embodiments of this application provide a control method for a refrigerant pump air conditioner, wherein the refrigerant pump air conditioner is the refrigerant pump air conditioner provided in the first aspect embodiment, such as... Figure 2 As shown, the control method for refrigerant pump air conditioners includes:

[0056] Step 101: Obtain the pre-pump subcooling value of refrigerant pump 1 in real time;

[0057] Step 102: When the subcooling value before the pump is less than or equal to the subcooling judgment value, open the bypass control valve 121.

[0058] Specifically, in combination Figure 1 As shown, the subcooling value before the pump refers to the difference between the temperature of the condensate of the first heat exchange medium located upstream of the refrigerant pump 1 and the saturation temperature at a certain pressure. The subcooling value before the pump can be calculated by obtaining the pressure value and temperature value before the pump from the pressure sensor 13 and temperature sensor 14 located upstream of the refrigerant pump 1.

[0059] The subcooling threshold is a control parameter used to determine whether the subcooling value before the pump is within a safe range. The subcooling threshold can be manually input into the control system of the refrigerant pump air conditioner, or it can be preset within the control system. In practical applications, the setting of the subcooling threshold needs to consider factors such as the operating efficiency of refrigerant pump 1, its safe operating range, and environmental conditions.

[0060] When the subcooling value before the pump is lower than the subcooling judgment value, the subcooling value before the pump is low, making it easy for the first heat exchange medium to generate flash gas, leading to cavitation of the pump. At this time, the bypass control valve 121 can be opened to connect the refrigerant pump 1 and the regenerator 2, allowing some of the low-temperature first heat exchange medium to enter the second regenerating channel of the regenerator 2 and exchange heat with the high-temperature first heat exchange medium flowing in the first regenerating channel of the regenerator 2. This preheating of the high-temperature first heat exchange medium before it enters the heat exchanger 4 increases the subcooling value before the pump. By precooling the first heat exchange medium, the temperature of the first heat exchange medium at the evaporator inlet is lower, resulting in a lower evaporation temperature in the evaporator and improving the heat exchange effect of the evaporator. This ensures that the indoor temperature is less prone to fluctuation when the evaporator 5 is running under high load, maintaining temperature stability and avoiding shutdown problems caused by cavitation of the refrigerant pump due to a sudden increase in load.

[0061] In some embodiments, the control method for a refrigerant pump air conditioner further includes step 103, which involves unlocking the operating frequency limit of the compressor 6 and increasing the operating frequency of the compressor 6 when the subcooling value before the pump is less than or equal to the subcooling determination value and the bypass control valve 121 is in the open state.

[0062] Specifically, the operating frequency limit of compressor 6 refers to setting an upper limit on the operating frequency of the variable frequency compressor 6 under normal operating conditions. Since the variable frequency compressor 6 can automatically increase its operating frequency as the load increases, locking the upper limit of the compressor 6's frequency can prevent problems such as overheating and damage caused by prolonged high-frequency operation under high load.

[0063] After opening the bypass control valve 121, if the subcooling value before the pump is still less than or equal to the subcooling judgment value, the restriction on the operating frequency of the compressor 6 can be temporarily unlocked, allowing the compressor 6 to operate at a higher frequency, increasing the pressure and flow velocity of the second heat exchange medium, thereby accelerating the temperature of the first heat exchange medium at the inlet of the heat exchanger 4, and further increasing the subcooling value before the pump.

[0064] It should be noted that when the subcooling value before the pump is less than or equal to the subcooling judgment value, the opening of the bypass control valve 121 and the limitation of the operating frequency of the compressor 6 can be implemented gradually. For example... Figure 3 As shown: When the subcooling value before the pump is less than or equal to the subcooling judgment value, it is determined whether the bypass control valve 121 is open; if the bypass control valve 121 is closed, the bypass control valve 121 is opened; if the bypass control valve 121 is open, it is determined whether the operating frequency limit of the compressor 6 is unlocked, and if the operating frequency limit of the compressor 6 is not unlocked, the operating frequency limit of the compressor 6 is unlocked and the operating frequency of the compressor 6 is increased.

[0065] Furthermore, if the subcooling value before the pump remains less than or equal to the subcooling threshold after unlocking the operating frequency limit of compressor 6 and increasing its operating frequency, an alarm can be triggered. For example, an audible and visual alarm signal can be sent to maintenance personnel, and the entire refrigerant pump air conditioner can be shut down, enabling maintenance personnel to perform maintenance work in a timely manner and preventing malfunctions in the refrigerant pump air conditioner.

[0066] In some embodiments, the control method for a refrigerant pump air conditioner further includes step 104, which involves reducing the operating frequency of the compressor 6 and locking the upper limit of the operating frequency of the compressor 6 when the subcooling value before the pump is greater than the subcooling protection stop value; wherein the subcooling protection stop value is greater than the subcooling determination value.

[0067] Specifically, the subcooling protection stop value is a control parameter used to determine whether the subcooling value before the pump has returned to a safe range. It can be manually input into the control system of the refrigerant pump air conditioner or preset in the control system. When the subcooling value before the pump is greater than the subcooling protection stop value, it indicates that the subcooling before the pump has returned to normal. At this time, the operating frequency of compressor 6 can be reduced, and the upper limit of the operating frequency of compressor 6 can be locked again to avoid overheating damage caused by prolonged high-frequency operation of compressor 6, and also to reduce the operating energy consumption of the refrigerant pump air conditioner.

[0068] The overcooling protection stop value should be greater than the overcooling judgment value, so that the overcooling protection action is turned off after the subcooling degree before the pump recovers to a higher level, thus ensuring the stability of indoor temperature control by the refrigerant pump air conditioner.

[0069] In some embodiments, the control method for a refrigerant pump air conditioner further includes step 105, closing the bypass control valve 121 when the subcooling value before the pump is greater than the subcooling protection stop value.

[0070] When the subcooling value before the pump is greater than the subcooling protection stop value, if the bypass control valve 121 is in the open state, the bypass control valve 121 can be closed to disconnect the connection between the refrigerant pump 1 and the regenerator 2, so that the first heat exchange medium can be normally delivered from the refrigerant pump 1 to the evaporator 5 side.

[0071] It should be noted that when the subcooling value before the pump exceeds the subcooling protection stop value, closing the bypass control valve 121 and reducing the operating frequency of compressor 6 can be done gradually, for example... Figure 3 As shown: When the subcooling value before the pump is greater than the subcooling judgment value, and the subcooling value before the pump is greater than the subcooling protection stop value, it is determined whether the compressor 6 has unlocked the operating frequency limit; when the compressor 6 is unlocked, the operating frequency of the compressor 6 is reduced and the upper limit of the operating frequency of the compressor 6 is locked; when the compressor 6 is not unlocked, it is determined whether the bypass control valve 121 is open, and when the bypass control valve 121 is open, the bypass control valve 121 is closed.

[0072] In summary, by acquiring and updating the subcooling value before the pump in real time, when the subcooling value is low, the bypass control valve 121 is opened in time or the operating frequency of the compressor 6 is increased to meet the needs when the load on the evaporator 5 side suddenly increases, thereby improving the stability of the refrigerant pump air conditioner in controlling the indoor temperature. After the subcooling value returns to normal, the bypass control valve 121 is closed in time or the operating frequency of the compressor 6 is reduced to reduce the energy consumption of the refrigerant pump air conditioner.

[0073] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A refrigerant pump air conditioner, characterized in that, Includes the first circulation assembly and heat exchanger; The first circulation assembly includes an evaporator, a refrigerant pump, and a regenerator. The regenerator has a first regenerator channel and a second regenerator channel that can exchange heat with each other. An input pipe is connected between the output end of the refrigerant pump and the input end of the evaporator. An output pipe is connected to the output end of the evaporator. The output pipe is connected to the input end of the first regenerator channel. The heat exchanger has a first heat exchange channel. The output end of the first heat exchange channel is connected to the input end of the first heat exchange channel. The output end of the first heat exchange channel is connected to the input end of the refrigerant pump. A bypass pipeline is connected between the output end of the fluorine pump and the input end of the second regenerative channel. The output end of the second regenerative channel is connected to the input pipeline, and a bypass control valve is connected to the bypass pipeline.

2. The refrigerant pump air conditioner according to claim 1, characterized in that, The first circulation component further includes a pressure sensor and a temperature sensor, both of which are located upstream of the fluorine pump and are used to acquire the pump inlet pressure and pump inlet temperature values, respectively.

3. The refrigerant pump air conditioner according to claim 1, characterized in that, The first circulation component further includes a one-way valve and a storage tank. The one-way valve is connected between the output end of the second regenerative channel and the output pipeline. The output end of the first heat exchange channel is connected to the input end of the storage tank, and the output end of the storage tank is connected to the input end of the fluorine pump.

4. The refrigerant pump air conditioner according to claim 1, characterized in that, The refrigerant pump air conditioner also includes a second circulation component, which includes a compressor, a first condenser, and a throttling device. The output end of the compressor is connected to the input end of the first condenser, and the output end of the first condenser is connected to the input end of the throttling device. The heat exchanger also has a second heat exchange channel that exchanges heat with the first heat exchange channel. The output end of the throttling device is connected to the input end of the second heat exchange channel, and the output end of the second heat exchange channel is connected to the input end of the compressor.

5. The refrigerant pump air conditioner according to claim 4, characterized in that, The first circulation assembly further includes a second condenser, which is arranged side by side with the first condenser and is located upstream of the first condenser; A first branch pipe is connected between the output pipe and the input end of the second condenser, and a first control valve is provided on the first branch pipe. The output end of the second condenser is connected to the first input end of the regenerator. A second branch pipe is connected between the output pipe and the input end of the first regenerator channel, and a second control valve is provided on the second branch pipe.

6. The refrigerant pump air conditioner according to any one of claims 1-5, characterized in that, A liquid ball valve is installed on the side of the input pipeline near the evaporator; a gas ball valve is installed on the side of the output pipeline near the evaporator.

7. A control method for a refrigerant pump air conditioner, characterized in that, The refrigerant pump air conditioner includes a first circulation component and a heat exchanger. The first circulation component includes a refrigerant pump and a regenerator. The input end of the refrigerant pump is connected to the output end of a first regenerator channel of the regenerator. The output end of the refrigerant pump is connected to the input end of a second regenerator channel of the regenerator via a bypass pipe. A bypass control valve is provided on the bypass pipe. The heat exchanger has a first heat exchange channel. The output end of the first regenerator channel is connected to the input end of the first heat exchange channel. The output end of the first heat exchange channel is connected to the input end of the refrigerant pump. The control method includes: The pre-pump subcooling value of the fluorine pump is obtained in real time; When the subcooling value before the pump is less than or equal to the subcooling determination value, the bypass control valve is opened.

8. The control method for a refrigerant pump air conditioner according to claim 7, characterized in that, The refrigerant pump air conditioner also includes a second circulation component, wherein the first circulation component and the second circulation component exchange heat through the heat exchanger, and the second circulation component includes a compressor; The control method further includes: when the subcooling value before the pump is less than or equal to the subcooling judgment value and the bypass control valve is in the open state, unlocking the operating frequency limit of the compressor and increasing the operating frequency of the compressor.

9. The control method for a refrigerant pump air conditioner according to claim 8, characterized in that, The control method further includes: When the subcooling value before the pump is greater than the subcooling protection stop value, the operating frequency of the compressor is reduced, and the maximum operating frequency of the compressor is limited to a locked frequency; the subcooling protection stop value is greater than the subcooling determination value.

10. The control method for a refrigerant pump air conditioner according to claim 8 or 9, characterized in that, The control method further includes: When the subcooling value before the pump exceeds the subcooling protection stop value, the bypass control valve is closed.

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