A heat pump system with integrated heat pipe heat exchanger and control method thereof

Abstract

The present invention discloses a heat pump system with an integrated heat pipe heat exchanger and a control method thereof, which relate to the technical field of air conditioning. A first branch pipe and a second branch pipe are controlled by a switching valve group so that the first heat exchanger and / or the second heat exchanger are connected to the main pipeline; when heating the room, the first heat exchanger and the second heat exchanger are all connected to the main pipeline for heating; when defrosting, one of the two heat exchangers is connected to the main pipeline for heating, and the other forms an independent circulation flow through a circulation pipeline, and the independent circulation flow loop is defrosted and heated by a heater; when one of the heat exchangers is defrosted, the other heat exchanger still maintains a normal working state, thereby maintaining the thermal comfort of the indoor environment; only the loop formed by one of the heat exchangers is heated, and there is no need to heat the medium of the large cycle. The heat pipe can efficiently transmit heat, so that the heat can be quickly transferred from the heating part to the whole during the defrosting process, thereby accelerating the melting of the frost layer of the heat exchanger and shortening the defrosting cycle.

Description

Technical Field

[0001] The present invention relates to the technical field of heat pump air conditioners, and further to a heat pump system integrating a heat pipe heat exchanger and a control method thereof. Background Art

[0002] The cooling process is to transfer indoor heat to outdoor heat, and the heating process is to transfer outdoor heat to indoor heat.

[0003] Heat pumps can consume a small amount of energy to transfer heat from a low-temperature environment to a high-temperature environment to achieve efficient cooling or heating. They have become a key solution for building energy conservation and carbon reduction. Among them, air source heat pumps are widely used due to their simple and easy control and low initial investment. However, when air source heat pumps are running in winter, the outdoor ambient temperature is low. The (outdoor) evaporator needs to lower the evaporation temperature below the outdoor environment to absorb heat. When the surface temperature is below 0 ℃, frost occurs. The frost layer will weaken the heat absorption capacity of the evaporator, resulting in a decrease in evaporation pressure and an increase in heat pump energy consumption. This phenomenon is more obvious in low temperature and high humidity areas. The accumulation of frost not only increases energy consumption, but a thick frost layer will cause the heat pump system to shut down. Therefore, defrosting is an important part of the operation of air source heat pumps.

[0004] Common defrosting methods include shutdown defrosting, electric heating defrosting, reverse cycle defrosting and hot gas bypass defrosting. Shutdown defrosting requires the equipment to be completely shut down, which leads to an unstable indoor environment; electric heating defrosting is fast but consumes a lot of power and has low heat utilization; reverse cycle defrosting requires reversing the heat pump cycle to reduce indoor comfort; hot gas bypass defrosting takes a long time and requires high compressor output power.

[0005] In summary, how to achieve defrosting while ensuring a comfortable indoor environment is a problem that currently needs to be solved urgently by those skilled in the art. Summary of the invention

[0006] The present invention provides a heat pump system with an integrated heat pipe heat exchanger, which only heats and defrosts the heat exchanger that needs to be defrosted, and other heat exchangers maintain a normal indoor heating state, thereby achieving defrosting while ensuring a comfortable indoor environment. The heater only needs to heat a small amount of circulating medium, thereby reducing the defrosting energy consumption. The specific scheme is as follows:

[0007] A heat pump system with an integrated heat pipe heat exchanger comprises an outdoor heat exchange component and a heater, wherein the outdoor heat exchange component is connected to a main pipe;

[0008] The outdoor heat exchange assembly includes a first heat exchanger, a second heat exchanger, a first branch pipe, a second branch pipe, a circulation pipeline, and a switching valve group. The first heat exchanger is connected to the main pipeline through the first branch pipe, and the second heat exchanger is connected to the main pipeline through the second branch pipe.

[0009] The switching valve group is used to control the first branch pipe and the second branch pipe so that the first heat exchanger and / or the second heat exchanger are connected to the main pipe;

[0010] When in the indoor heating state, the first heat exchanger and the second heat exchanger are all connected to the main pipeline for heating, and the indoor heat exchanger is used to release heat to the room;

[0011] When in the defrosting state, one of the first heat exchanger or the second heat exchanger is connected to the main pipeline for heating; the other one forms an independent circulation flow through the circulation pipeline and performs defrosting heating through the heater.

[0012] Optionally, the first heat exchanger and the second heat exchanger share the same circulation pipeline;

[0013] The switching valve group includes a first four-way valve and a second four-way valve. The first four-way valve is connected to the main line, the first branch pipe, the second branch pipe, and the circulation line to achieve inlet control; the second four-way valve is connected to the main line, the first branch pipe, the second branch pipe, and the circulation line to achieve outlet control.

[0014] Optionally, the switching valve group includes a first three-way valve, a second three-way valve, a third three-way valve, and a fourth three-way valve, wherein the first three-way valve is arranged at the outlet section of the first branch pipe, the second three-way valve is arranged at the outlet section of the second branch pipe, the third three-way valve is arranged at the inlet section of the first branch pipe, and the fourth three-way valve is arranged at the inlet section of the second branch pipe;

[0015] The circulation pipeline includes a first circulation pipeline and a second circulation pipeline, the first circulation pipeline is connected between the first three-way valve and the third three-way valve, and the second circulation pipeline is arranged between the second three-way valve and the fourth three-way valve.

[0016] Optionally, the first heat exchanger and the second heat exchanger are integrated side by side.

[0017] Optionally, the heater is an electric heating wire arranged at the bottom of the first heat exchanger and the second heat exchanger, and a heat pipe cycle is formed by using the density difference of the phase change medium as a circulation power.

[0018] Optionally, it also includes an indoor heat exchanger, a throttle valve, a gas-liquid separator, a compressor, and a four-way reversing valve arranged in the main line.

[0019] Optionally, it also includes temperature sensors arranged on the first heat exchanger and the second heat exchanger, which are used to judge the frosting state according to the temperature value. Below -2°C and above -6°C is light frosting, and below -6°C is heavy frosting.

[0020] Optionally, the temperature sensor performs a cyclic detection and judgment every predetermined time.

[0021] Optionally, the temperature change value, visualization, or EER is used as a control dead zone, and the mode is switched when the change exceeds the control dead zone.

[0022] The present invention further provides a heat pipe heat exchanger control method, which is applied to a heat pump system with an integrated heat pipe heat exchanger as described in any one of the above, comprising:

[0023] Determine the current state:

[0024] When in the indoor heating state, the first heat exchanger and the second heat exchanger are all connected to the main pipeline for heating. At this time, the indoor heat exchanger is used to release heat to the room, and the circulation pipeline does not participate in the medium flow;

[0025] When in the defrosting state, the first heat exchanger is connected to the main pipeline for heating; the second heat exchanger forms an independent circulation flow through the circulation pipeline, and the second heat exchanger is defrosted and heated by the heater provided in the second heat exchanger;

[0026] Determine whether the defrosting process of the second heat exchanger is completed, if not, continue defrosting and heating, if yes, connect the second heat exchanger to the main pipeline for heating, and form an independent circulation flow through the first heat exchanger through the circulation pipeline, and defrost and heat the first heat exchanger through the heater set by the first heat exchanger;

[0027] Determine whether the defrosting process of the first heat exchanger is completed. If not, continue defrosting and heating. If yes, connect the first heat exchanger to the main pipeline for heating and switch to the indoor heating state.

[0028] The present invention provides a heat pump system with an integrated heat pipe heat exchanger, wherein an outdoor heat exchange component is connected to a main pipeline, and the outdoor heat exchange component comprises a first heat exchanger and a second heat exchanger, the first heat exchanger is connected to the main pipeline through a first branch pipe, and the second heat exchanger is connected to the main pipeline through a second branch pipe, and the first branch pipe and the second branch pipe are controlled by a switching valve group so that the first heat exchanger and / or the second heat exchanger are connected to the main pipeline; when in an indoor heating state, the first heat exchanger and the second heat exchanger are all connected to the main pipeline for heating; when in a defrosting state, one of the first heat exchanger and the second heat exchanger is connected to the main pipeline for heating, and the other forms an independent circulation flow through a circulation pipeline, and the independent circulation flow loop is defrosted and heated by a heater, and by adopting this defrosting method, when one of the heat exchangers is defrosted, the other heat exchanger still maintains a normal working state, and the thermal comfort of indoor personnel is maintained under the premise of maximizing the heating effect. During heating, only the loop formed by one of the heat exchangers is heated, and there is no need to heat the medium of the large cycle. The heat pipe can efficiently transfer heat, so that the heat can be quickly transferred from the heating part to the whole during the defrosting process. It not only uses the efficient heat transfer characteristics of the heat pipe to shorten the defrosting cycle and reduce energy consumption, but also effectively reduces the energy waste caused by local overheating in traditional electric heating methods. In addition, due to the efficient heat transfer and uniform temperature characteristics of the heat pipe, the heat is evenly transferred from the pipe to the outer frost layer during the defrosting process, which causes the frost layer to fall off before it is completely melted, thereby further reducing the time and energy consumption required for defrosting and optimizing the energy efficiency of the entire defrosting process. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0030] Figure 1 It is a schematic diagram of the overall structure of an embodiment of a heat pump system integrated with a heat pipe heat exchanger of the present invention;

[0031] Figure 2 A schematic diagram of a piping system of a first embodiment of an outdoor heat exchange component;

[0032] Figure 3 This is a schematic diagram of the indoor heating state of the first embodiment of the outdoor heat exchange component applied to the entire system;

[0033] Figure 4 It is a schematic diagram of the right side defrosting state of the first embodiment of the outdoor heat exchange component applied to the entire system;

[0034] Figure 5It is a schematic diagram of the defrosting state of the left side of the entire system when the first embodiment of the outdoor heat exchange component is applied;

[0035] Figure 6 A schematic diagram of the indoor heating state of the second embodiment of the outdoor heat exchange assembly;

[0036] Figure 7 It is a schematic diagram of the right side defrosting state of the second embodiment of the outdoor heat exchange component;

[0037] Figure 8 This is a schematic diagram of the left side defrosting state of the second embodiment of the outdoor heat exchange component.

[0038] The figure includes:

[0039] Outdoor heat exchange assembly 1, first heat exchanger 11, second heat exchanger 12, first branch pipe 13, second branch pipe 14, circulation pipeline 15, first circulation pipeline 151, second circulation pipeline 152, switching valve group 16, first four-way valve 161, second four-way valve 162, first three-way valve 163, second three-way valve 164, third three-way valve 165, fourth three-way valve 166;

[0040] Heater 2, indoor heat exchanger 3, throttle valve 4, gas-liquid separator 5, compressor 6, four-way reversing valve 7. DETAILED DESCRIPTION

[0041] The core of the present invention is to provide a heat pump system with an integrated heat pipe heat exchanger. During defrosting, only the heat exchanger that needs to be defrosted is heated and defrosted, and other heat exchangers are still used to maintain the indoor heating state. Defrosting is achieved under the premise of maximizing the heating effect. The heater only needs to heat a small amount of circulating medium, which reduces the defrosting energy consumption.

[0042] In order to enable those skilled in the art to better understand the technical solution of the present invention, the heat pump system with integrated heat pipe heat exchanger of the present invention will be described in detail below with reference to the accompanying drawings and specific implementation methods.

[0043] The present invention provides a heat pump system with an integrated heat pipe heat exchanger, Figure 2 As shown, the system includes an outdoor heat exchange component 1 and a heater 2. The outdoor heat exchange component 1 is connected to the main pipeline. Figure 2M in the figure indicates the main line, which is the main line of the heat pump system with integrated heat pipe heat exchanger when it is working normally for cooling or heating. It is located between the outdoor heat exchange component 1 and the indoor heat exchanger 3, so that the medium forms a circulation flow between the outdoor heat exchange component 1 and the indoor heat exchanger 3; it can cool or heat indoors. When cooling indoors, the indoor heat exchanger 3 absorbs indoor heat and the outdoor heat exchange component 1 releases heat to the outside; when heating indoors, the outdoor heat exchange component 1 absorbs outdoor heat and the indoor heat exchanger 3 releases heat to the indoors. The defrosting targeted in this article refers to the situation where the outdoor heat exchange component 1 is frosted in the indoor heating mode.

[0044] The outdoor heat exchange assembly 1 includes a first heat exchanger 11, a second heat exchanger 12, a first branch pipe 13, a second branch pipe 14, a circulation pipeline 15, and a switching valve group 16. The first heat exchanger 11 is connected to the main pipeline through the first branch pipe 13, and the second heat exchanger 12 is connected to the main pipeline through the second branch pipe 14. It should be noted that in the embodiment shown in the drawings of the present invention, two heat exchangers (the first heat exchanger 11 and the second heat exchanger 12) are set as an example for display, but the present invention does not exclude the setting of a larger number of heat exchangers, such as more than three, and these specific number settings should be included in the protection scope of the present invention. The present invention is provided with more than two heat exchangers, and each heat exchanger is set in parallel with each other. Each heat exchanger can independently control and adjust the working state, and the switching of the working state is mainly achieved by adjusting the switching valve group 16; when there are more heat exchangers, corresponding matching branch pipes, circulation pipes and switching valves are required. For the convenience of explanation, the following is an introduction to the setting of two heat exchangers as an example. Each heat exchanger is provided with a heater 2, and the medium in the heat exchanger is heated and increased in temperature by the heater 2.

[0045] The switching valve group 16 is used to control the first branch pipe 13 and the second branch pipe 14 so that the first heat exchanger 11 and / or the second heat exchanger 12 are connected to the main line. There are three situations here: 1) both the first heat exchanger 11 and the second heat exchanger 12 are connected to the main line, 2) the first heat exchanger 11 is connected to the main line, and 3) the second heat exchanger 12 is connected to the main line.

[0046] Specifically, combined Figure 3 , Figure 6 As shown, when in the indoor heating state, the first heat exchanger 11 and the second heat exchanger 12 are all connected to the main pipeline for heating. At this time, the first heat exchanger 11 and the second heat exchanger 12 are both involved in indoor heating, and the indoor heat exchanger 3 is used to release heat to the room. At this time, the circulation pipeline 15 does not participate in the medium flow.

[0047] When in the defrosting state, one of the first heat exchanger 11 or the second heat exchanger 12 is connected to the main pipeline for heating; the other forms an independent circulation flow through the circulation pipeline 15 and performs defrosting heating through the heater 2.

[0048] Combination Figure 4 , Figure 7 As shown, both represent defrosting on the right side. The black arrows in the figure represent the flow direction of the medium participating in the heating of the main line, and the hollow arrows represent the flow direction of the medium not participating in the flow of the main line to form an independent cycle. At this time, the second heat exchanger 12 on the left is connected to the main line for indoor heating cycle, and the first heat exchanger 11 on the right is no longer connected to the main line. The first heat exchanger 11, the first branch pipe 13 and the circulation pipeline 15 form an independent circulation loop. The medium in the first heat exchanger 11 flows out and then flows back to the first heat exchanger 11 through circulation. During the circulation of the medium in the first heat exchanger 11, when the medium flows through the heater 2, the medium can be heated. The heated medium circulates and flows through various positions of the first heat exchanger 11, and the entire first heat exchanger 11 can be heated to achieve heating defrosting.

[0049] Correspondingly, combined Figure 5 , Figure 8 As shown, both represent left-side defrosting. The black arrows in the figure represent the flow direction of the medium participating in the heating of the main line, and the hollow arrows represent the flow direction of the medium not participating in the flow of the main line to form an independent cycle. At this time, the first heat exchanger 11 on the right is connected to the main line for indoor heating cycle, and the second heat exchanger 12 on the left is no longer connected to the main line. The second heat exchanger 12, the second branch pipe 14 and the circulation pipeline 15 form an independent circulation loop. The medium in the second heat exchanger 12 flows out and then flows back to the second heat exchanger 12 through the circulation. During the circulation of the medium in the second heat exchanger 12, when the medium flows through the heater 2, the medium can be heated. The heated medium circulates and flows through various positions of the second heat exchanger 12, and the entire second heat exchanger 12 can be heated to achieve heating defrosting.

[0050] The present invention adopts a parallel pipeline design of heat exchangers. No matter the left side defrosts (the second heat exchanger 12 defrosts) or the right side defrosts (the first heat exchanger 11 defrosts), only one of the heat exchangers forms a circulation heating defrost independently of the main pipeline, while the other heat exchanger remains connected to the main pipeline for indoor heating, ensuring that the compressor 6 does not stop working to maintain indoor heating while the system is performing a defrosting operation (heating by heater 2), thereby avoiding the wear of the compressor caused by the reverse cycle in the traditional defrosting method, and reducing the room temperature fluctuation to maintain the comfort of the indoor environment. For the first heat exchanger 11 and the second heat exchanger 12 that perform defrosting in an independent cycle, the heater 2 only needs to heat a small amount of medium, and does not need to heat the medium participating in the main pipeline circulation, which can reduce the energy consumption required for heating, and realizes that the system maintains efficient defrosting performance under the premise of maintaining low energy consumption.

[0051] In addition, the heat pump system of the integrated heat pipe heat exchanger of the present invention is different from the existing traditional defrosting method. The traditional defrosting adopts external heating to defrost, heats the outside of the pipe, and conducts heat from the outside to the inside. It is necessary to melt and remove the frost layer outside the pipe before heating the inside of the pipe. The defrosting direction of the present invention is to defrost evenly from the inside of the pipe to the outside. The side wall of the pipe is heated first, and the frost layer that melts first is also the frost layer on the inside of the pipe. Therefore, the frost layer will fall off before it is completely melted, saving defrosting time and power consumption.

[0052] Based on the above solution, the circulation pipeline 15 of the present invention can be arranged in different forms. The present invention provides two specific arrangements:

[0053] The first one is combined Figure 2 , Figure 3 , Figure 4 , Figure 5 The first heat exchanger 11 and the second heat exchanger 12 share the same circulation pipeline 15 , that is, no matter which heat exchanger performs independent circulation defrosting, the independent circulation processes of the first heat exchanger 11 and the second heat exchanger 12 are participated by the same circulation pipeline 15 .

[0054] In this structure, the switching valve group 16 includes a first four-way valve 161 and a second four-way valve 162. The first four-way valve 161 and the second four-way valve 162 are respectively provided with four valve ports, and the conduction state between the four valve ports can be changed. The flow direction of the medium is adjusted by changing the conduction state of the valve ports. The first four-way valve 161 is connected to the main pipeline, the first branch pipe 13, the second branch pipe 14, and the circulation pipeline 15, and is used to realize inlet control and control the medium to flow into the main pipeline; the second four-way valve 162 is connected to the main pipeline, the first branch pipe 13, the second branch pipe 14, and the circulation pipeline 15, and is used to realize outlet control and control the medium to flow out into the main pipeline. Reference Figure 2 The first four-way valve 161 includes four valve ports a1, b1, c1, and d1, and the second four-way valve 162 includes four valve ports a2, b2, c2, and d2.

[0055] Combination Figure 3 As shown, when indoor heating is performed, the first heat exchanger 11 and the second heat exchanger 12 are both connected to the main pipeline; at this time, d1 and d2 are closed, a1, b1, and c1 are opened, and a2, b2, and c2 are opened. The medium in the main pipeline flows into a1, and flows out from b1 and c1 respectively, flows to the second heat exchanger 12 through b1, and flows to the first heat exchanger 11 through c1; flows out from the second heat exchanger 12 into b2, flows out from the first heat exchanger 11 into c2, and the medium enters from b2 and c2 and then merges and is discharged from a2.

[0056] Combination Figure 4As shown, when the right side is defrosted, the second heat exchanger 12 is connected to the main line, and the first heat exchanger 11 circulates independently; at this time, a1, b1, c1, and d1 are all open, a1 and b1 are connected, c1 and d1 are connected, a2, b2, c2, and d2 are all open, a2 and b2 are connected, and c2 and d2 are connected. The medium in the main line flows into a1 and flows out from b1, flows to the second heat exchanger 12 through b1, flows out of the second heat exchanger 12 and enters b2, and flows out of a2 and enters the main line. The medium flows out of the first heat exchanger 11 and enters c2, and flows out from d2, enters d1 through the circulation pipeline 15, and flows back to the first heat exchanger 11 through c1 to form a cycle. The medium is heated when circulating through the heater 2.

[0057] Combination Figure 5 As shown, when the left side is defrosted, the first heat exchanger 11 is connected to the main line, and the second heat exchanger 12 circulates independently; at this time, a1, b1, c1, and d1 are all open, a1 and c1 are connected, b1 and d1 are connected, a2, b2, c2, and d2 are all open, a2 and c2 are connected, and b2 and d2 are connected. The medium in the main line flows into a1 and flows out from c1, flows to the first heat exchanger 11 through c1, flows out of the first heat exchanger 11 and enters c2, and flows out of a2 and enters the main line. The medium flows out of the second heat exchanger 12 and enters b2, and flows out from d2, enters d1 through the circulation pipeline 15, and flows back to the second heat exchanger 12 through b1 to form a cycle. The medium is heated when circulating through the heater 2.

[0058] The second type is combined Figure 6 , Figure 7 , Figure 8 , the first heat exchanger 11 is provided with a first circulation pipeline 151, and the second heat exchanger 12 is provided with a second circulation pipeline 152. In this embodiment, two independent circulation pipelines are provided, and each circulation pipeline is used for the circulation flow of one of the heat exchangers. The switching valve group 16 includes a first three-way valve 163, a second three-way valve 164, a third three-way valve 165, and a fourth three-way valve 166. The first three-way valve 163 is provided at the outlet section of the first branch pipe 13, the second three-way valve 164 is provided at the outlet section of the second branch pipe 14, the third three-way valve 165 is provided at the inlet section of the first branch pipe 13, and the fourth three-way valve 166 is provided at the inlet section of the second branch pipe 14; the first three-way valve 163, the second three-way valve 164, the third three-way valve 165, and the fourth three-way valve 166 are provided with three valve ports respectively, and the conduction relationship between the three valve ports can be adjusted. The three valve ports of the four valve groups are respectively connected between the corresponding branch pipes, the circulation pipelines, and the main pipelines.

[0059] The circulation pipeline 15 includes a first circulation pipeline 151 and a second circulation pipeline 152 . The first circulation pipeline 151 is connected between the first three-way valve 163 and the third three-way valve 165 . The second circulation pipeline 152 is disposed between the second three-way valve 164 and the fourth three-way valve 166 .

[0060] Combination Figure 6 As shown, when indoor heating is performed, the first heat exchanger 11 and the second heat exchanger 12 are both connected to the main pipeline; at this time, a1, a2, a3, and a4 are closed, and b1, c1, b2, c2, b3, c3, b4, and c4 are opened; the medium in the main pipeline is divided into two paths and flows into c3 and c4, flows to the second heat exchanger 12 through b3, and flows to the first heat exchanger 11 through b4; flows out of the second heat exchanger 12 and enters b1, flows out of the first heat exchanger 11 and enters b2, and flows out of c1 and c2 respectively and then merges into the main pipeline.

[0061] Combination Figure 7 As shown, when the right side is defrosted, the second heat exchanger 12 is connected to the main pipeline, and the first heat exchanger 11 circulates independently; a1 and a3 are closed, and all other valves are opened. The medium in the main pipeline flows into c3, flows to the second heat exchanger 12 through b3, flows out of the second heat exchanger 12 into b1, and flows out of c1 into the main pipeline. The medium in the first heat exchanger 11 flows out, passes through b2 and is discharged from a2, flows to a4 through the second circulation pipeline 152, and flows out from b4 and re-enters the first heat exchanger 11 to complete the cycle. The medium is heated when circulating through the heater 2.

[0062] Combination Figure 8 As shown, when the left side is defrosted, the first heat exchanger 11 is connected to the main line, and the second heat exchanger 12 circulates independently; a2 and a4 are closed, and all other valves are opened. The medium in the main line flows into c4, flows to the first heat exchanger 11 through b4, flows out of the first heat exchanger 11 into b2, and flows out of c2 into the main line. The medium in the second heat exchanger 12 flows out, passes through b1 and is discharged from a1, flows to a3 through the first circulation pipeline 151, and flows out from b3 and re-enters the second heat exchanger 12 to complete the cycle. The medium is heated when circulating through the heater 2.

[0063] In the two structures introduced above, both left-side defrosting and right-side defrosting can be realized. When defrosting, one of the heat exchangers is heated and defrosted first, and then switched to the other heat exchanger for heating and defrosting. It should be pointed out that during the switching process, when the heating and defrosting of one heat exchanger stops, it can be instantly switched to the other heat exchanger for heating and defrosting, or the two heat exchangers can be allowed to perform indoor heating process simultaneously for a period of time before switching.

[0064] Based on any of the above technical solutions and their combination, Figure 1As shown, the first heat exchanger 11 and the second heat exchanger 12 are integrated side by side, which is conducive to integration, miniaturization, and saving installation space. However, the present invention does not exclude the situation that the first heat exchanger 11 and the second heat exchanger 12 are independently arranged in the physical space. Although the first heat exchanger 11 and the second heat exchanger 12 are integrated into one, the heater 2 is still independently arranged to independently control the heating of the heater.

[0065] Specifically, the heater 2 used in the present invention is an electric heating wire arranged at the bottom of the first heat exchanger 11 and the second heat exchanger 12, and the electric heating wire is wound outside the coils of the first heat exchanger 11 and the second heat exchanger 12. The first heat exchanger 11 and the second heat exchanger 12 are filled with a phase change medium (also called a refrigerant), and the density difference of the phase change medium is used as a circulation power to form a heat pipe cycle. The phase change medium is heated at the bottom, and the medium changes from a liquid state to a gas state and flows upward. When it flows through the frosting area, it releases heat, melts the condensed frost, and the medium is cooled again to form a liquid state, which can flow back downward under the action of gravity. In this form, there is no need to set a power structure for the independent circulation heating and defrosting circuit, and automatic circulation flow is realized. The heater 2 uses an electric heating wire for easy control. In addition, it can also be in the form of water heating.

[0066] Combination Figure 1 , Figure 3 As shown, the heat pump system of the integrated heat pipe heat exchanger of the present invention also includes an indoor heat exchanger 3, a throttle valve 4, a gas-liquid separator 5, a compressor 6, and a four-way reversing valve 7 arranged in the main pipeline. The medium flows inside and passes through different structures to form indoor cooling or heating.

[0067] The heat pump system of the integrated heat pipe heat exchanger of the present invention further includes temperature sensors disposed on the first heat exchanger 11 and the second heat exchanger 12, which are used to determine the frosting state according to the temperature values. The present invention provides three optional frosting determination methods:

[0068] 1. Judging by the surface temperature of the heat exchanger:

[0069] Mild frosting: The surface temperature of the heat exchanger is between -2°C and -6°C, and the thickness of the frost layer is usually 1-4 mm.

[0070] Severe frosting: The heat exchanger surface temperature is below -6°C and the frost layer thickness is usually more than 4 mm.

[0071] 2. Directly judge by frost thickness (judgment by visual equipment such as cameras):

[0072] Light frost: The thickness of the frost layer is about 1-4 mm, and white frost begins to appear on the surface.

[0073] Severe frost: The frost layer is more than 4 mm thick and there is a thicker frost layer.

[0074] 3. System performance monitoring (based on energy efficiency ratio EER (where energy efficiency ratio is the ratio of cooling capacity to power consumption)):

[0075] Mild frost: EER drops slightly (5%-15%), and system operating efficiency is significantly reduced.

[0076] Severe frosting: The EER drops by more than 15%, the cooling capacity is obviously insufficient, and the frosting problem needs to be dealt with immediately.

[0077] The above are just three exemplary judgment methods. Only the judgment methods are different, and the operating states corresponding to the degree of frost are basically the same, that is, when the surface temperature of the heat exchanger is between -2°C and -6°C, the thickness of the frost layer is usually 1-4 mm, which can also be modified according to actual conditions. Differentiating between light frost and heavy frost can enable the heater 2 to use different heating powers, with a higher heating power for heavy frost, and more targeted defrosting and energy saving.

[0078] The defrosting mode adopted by the present invention is sequential defrosting. While one heat exchanger is defrosted by heat pipe circulation heating, the remaining heat exchangers can use the waste heat of electric heating to improve the operating efficiency and slow down the accumulation of frost on the surface of the heat exchanger, reduce the temperature difference of electric heating, promote the defrosting of the next cycle, form a self-enhancing circulation mechanism, and improve the overall energy efficiency of the system.

[0079] In addition, the temperature sensor can also be used as a basis for judging whether defrosting is completed. When the first heat exchanger 11 or the second heat exchanger 12 performs cyclic defrosting, the corresponding temperature sensor detects that the temperature value reaches a certain set temperature and is maintained for a predetermined time, indicating that defrosting is completed and the defrosting of the corresponding heat exchanger can be stopped.

[0080] When judging light frost and heavy frost, the temperature sensor performs a cyclic detection and judgment every predetermined time, for example, once every 2 minutes. For example, when it is judged as light frost, low power heating is used; after 2 minutes, a second judgment is made. If it is still in a light frost state, the heating power is increased. If the heat exchanger temperature exceeds 0 ℃ at this time, the heating is stopped. On the contrary, if it is judged as heavy frost, high power heating is directly used; after 2 minutes, a second judgment is made. If it turns into a light frost state at this time, the heating power is reduced. If it is still heavy frost, high power heating is maintained; and a third judgment is made after 2 minutes. If the temperature is higher than 0 ℃, the heating is stopped. This control strategy achieves a balance between effective energy utilization and defrosting efficiency.

[0081] In order to prevent the valve from frequently starting and stopping, the temperature change value, visualization, or EER is used as the control dead zone, and the mode is switched when the change exceeds the control dead zone. If the temperature change value is used as the control dead zone, taking 2 °C as an example, the mode is switched only when the temperature change exceeds the set threshold range and reaches 2 °C, and the mode is not switched if the temperature change does not reach 2 °C. For example, the two temperature zones are: -2 °C ~-6 °C, >-6 °C. When the system is running in the mode corresponding to light frost, the temperature reaches -8 °C before entering the operation mode corresponding to heavy frost. Conversely, when the system is running in the mode corresponding to heavy frost, the system enters the operation mode corresponding to light frost when the temperature rises to -4 °C. Similarly, if visual judgment is used, the dead zone is set to 1 mm of frost thickness. For example, when the frost thickness change does not exceed 1 mm, the mode is not switched, and if the thickness change exceeds 1 mm, the mode is switched. If the EER is used for judgment, the dead zone is set to 3% of the change in the energy efficiency ratio (EER). For example, when the change in the energy efficiency ratio (EER) does not exceed 3%, the mode is not switched. If the change in the energy efficiency ratio (EER) exceeds 3%, the mode is switched. The present invention combines heat pipe technology, electric heating technology and air-conditioning air heat exchanger, performs simple circuit transformation on the basis of the existing heat exchanger, and has a high degree of structural integration. By using a small amount of electric heating energy and combining the uniform temperature characteristics of the heat pipe, an efficient mode of lower electric heating defrosting and upper heat pipe defrosting is formed, which effectively promotes uniform defrosting of the entire heat exchanger surface and reduces the dissipation of electric heating energy to the air, thereby solving the energy waste problem inherent in the traditional electric heating method. Furthermore, the efficient heat transfer characteristics of the heat pipe are used to shorten the defrosting cycle and reduce energy consumption. At the same time, its uniform temperature characteristics promote uniform heat conduction from the pipe to the frost layer, resulting in the frost layer falling off before it is completely melted. The combination of the two significantly reduces the time period required for electric heating and improves the energy utilization rate of electric heating. Based on this structure, the system achieves efficient defrosting performance under the premise of low energy consumption. In addition, a parallel piping design is adopted to ensure that the compressor does not stop working while the system is performing defrosting operations, thereby avoiding compressor wear caused by reverse circulation and reducing room temperature fluctuations to maintain the comfort of the indoor environment.

[0082] The present invention provides a heat pipe heat exchanger control method, which is applied to the heat pump system integrated with the heat pipe heat exchanger involved above, and comprises the following steps:

[0083] The current state is determined, and corresponding operations are performed according to different states, and the flow direction of the phase change medium inside the pipeline and the working state of related devices are switched. The present invention is aimed at outdoor defrosting during indoor heating, and therefore includes two states, namely, indoor heating state and defrosting state. The indoor heating state refers to the process of only indoor heating, and the defrosting state refers to the process of still heating the indoor room while defrosting.

[0084] When the indoor heating state is in progress, the switching valve group 16 is controlled to connect the first heat exchanger 11 and the second heat exchanger 12 to the main pipeline for heating. At this time, the phase change medium in the pipeline carries heat and is dissipated to the indoor room through the indoor heat exchanger 3, so that the indoor room is heated; the temperature of the phase change medium decreases after passing through the indoor heat exchanger 3. In the indoor heating state, the circulation pipeline 15 does not participate in the medium flow, and the phase change medium does not need to pass through the circulation pipeline 15.

[0085] When in the defrosting state, the first heat exchanger 11 is connected to the main pipeline for heating. At this time, the indoor heat exchanger 3 is used to release heat to the room to maintain the normal heating process in the room; the second heat exchanger 12 forms an independent circulation flow through the circulation pipeline 15, and the heater 2 provided on the second heat exchanger 12 defrosts and heats the second heat exchanger 12. At this time, only one heat exchanger maintains the indoor heating process, and the other heat exchanger defrosts itself.

[0086] As the second heat exchanger 12 performs defrosting and heating, it is necessary to periodically determine whether the defrosting process of the second heat exchanger 12 is completed. If not, defrosting and heating will continue. If yes, the switching valve group 16 will be controlled to connect the second heat exchanger 12 to the main pipeline for heating; the switching valve group 16 will be controlled to stop the indoor heating process of the first heat exchanger 11, and the first heat exchanger 11 will form an independent circulation flow through the circulation pipeline 15, and the first heat exchanger 11 will be defrosted and heated by the heater 2 set in the first heat exchanger 11. At this time, only one heat exchanger maintains the indoor heating process, and the other heat exchanger performs its own defrosting.

[0087] It is determined whether the defrosting process of the first heat exchanger 11 is completed. If not, defrosting and heating are continued. If yes, the first heat exchanger 11 is connected to the main pipeline for heating and switched to indoor heating state. When the two heat exchangers complete the defrosting process in turn, the normal indoor heating state can be restored. The two heat exchangers heat the room at the same time and release heat to the room.

[0088] In this method, the specific form of the switching valve group 16 can refer to the above-mentioned heat pump system with integrated heat pipe heat exchanger. A circulation pipeline 15 can be provided with two four-way valves, or two circulation pipelines 15 can be provided with four three-way valves. The present invention will not be repeated here.

[0089] In addition, the defrosting of the first heat exchanger 11 and the second heat exchanger 12 can be judged based on the temperature value detected by the above-mentioned temperature sensor, and the above-mentioned control dead zone can be used to avoid frequent start and stop.

[0090] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A heat pump system with integrated heat pipe heat exchanger, characterized in that: It comprises an outdoor heat exchange component (1) and a heater (2), wherein the outdoor heat exchange component (1) is connected to a main pipe; The outdoor heat exchange assembly (1) comprises a first heat exchanger (11), a second heat exchanger (12), a first branch pipe (13), a second branch pipe (14), a circulation pipeline (15), and a switching valve group (16); the first heat exchanger (11) is connected to the main pipeline via the first branch pipe (13), and the second heat exchanger (12) is connected to the main pipeline via the second branch pipe (14); The switching valve group (16) is used to control the first branch pipe (13) and the second branch pipe (14) so ​​that the first heat exchanger (11) and / or the second heat exchanger (12) are connected to the main pipe; When in the indoor heating state, the first heat exchanger (11) and the second heat exchanger (12) are both connected to the main pipeline for heating; When in the defrosting state, one of the first heat exchanger (11) or the second heat exchanger (12) is connected to the main pipeline for heating; the other forms an independent circulation flow through the circulation pipeline (15) and performs defrosting heating through the heater (2).

2. The heat pump system with integrated heat pipe heat exchanger according to claim 1, characterized in that: The first heat exchanger (11) and the second heat exchanger (12) share the same circulation pipeline (15); The switching valve group (16) comprises a first four-way valve (161) and a second four-way valve (162); the first four-way valve (161) is connected to the main pipeline, the first branch pipe (13), the second branch pipe (14), and the circulation pipeline (15) for realizing inlet control; the second four-way valve (162) is connected to the main pipeline, the first branch pipe (13), the second branch pipe (14), and the circulation pipeline (15) for realizing outlet control.

3. The heat pump system with integrated heat pipe heat exchanger according to claim 1, characterized in that: The switching valve group (16) comprises a first three-way valve (163), a second three-way valve (164), a third three-way valve (165), and a fourth three-way valve (166); the first three-way valve (163) is arranged at the outlet section of the first branch pipe (13), the second three-way valve (164) is arranged at the outlet section of the second branch pipe (14), the third three-way valve (165) is arranged at the inlet section of the first branch pipe (13), and the fourth three-way valve (166) is arranged at the inlet section of the second branch pipe (14); The circulation pipeline (15) comprises a first circulation pipeline (151) and a second circulation pipeline (152); the first circulation pipeline (151) is connected between the first three-way valve (163) and the third three-way valve (165); and the second circulation pipeline (152) is arranged between the second three-way valve (164) and the fourth three-way valve (166).

4. The heat pump system with integrated heat pipe heat exchanger according to any one of claims 1 to 3, characterized in that: The first heat exchanger (11) and the second heat exchanger (12) are integrated side by side.

5. The heat pump system with integrated heat pipe heat exchanger according to any one of claims 1 to 3, characterized in that: The heater (2) is an electric heating wire arranged at the bottom of the first heat exchanger (11) and the second heat exchanger (12), and uses the density difference of the phase change medium as a circulation power to form a heat pipe circulation.

6. The heat pump system with integrated heat pipe heat exchanger according to any one of claims 1 to 3, characterized in that: It also includes an indoor heat exchanger (3), a throttle valve (4), a gas-liquid separator (5), a compressor (6), and a four-way reversing valve (7) arranged on the main pipeline.

7. The heat pump system with integrated heat pipe heat exchanger according to claim 6, characterized in that: It also includes temperature sensors disposed on the first heat exchanger (11) and the second heat exchanger (12), which are used to judge the frosting state according to the temperature value, where a temperature below -2°C and above -6°C is considered light frosting, and a temperature below -6°C is considered heavy frosting.

8. The heat pump system with integrated heat pipe heat exchanger according to claim 7, characterized in that: The temperature sensor performs a cycle detection and judgment every predetermined time.

9. The heat pump system with integrated heat pipe heat exchanger according to claim 8, characterized in that: Use temperature change value, visualization, or EER as the control dead zone, and switch modes when the change exceeds the control dead zone.

10. A heat pipe heat exchanger control method, characterized in that: A heat pump system for an integrated heat pipe heat exchanger according to any one of claims 1 to 9, comprising: Determine the current state: When in the indoor heating state, the first heat exchanger (11) and the second heat exchanger (12) are all connected to the main pipeline for heating, and the circulation pipeline (15) does not participate in the flow of the medium; When in the defrosting state, the first heat exchanger (11) is connected to the main pipeline for heating; the second heat exchanger (12) forms an independent circulation flow through the circulation pipeline (15), and the second heat exchanger (12) is defrosted and heated by the heater (2) provided on the second heat exchanger (12); Determining whether the defrosting process of the second heat exchanger (12) is completed, and if not, continuing defrosting and heating; if yes, connecting the second heat exchanger (12) to the main pipeline for heating, and forming an independent circulation flow through the first heat exchanger (11) through the circulation pipeline (15), and defrosting and heating the first heat exchanger (11) through the heater (2) provided in the first heat exchanger (11); It is determined whether the defrosting process of the first heat exchanger (11) is completed. If not, defrosting and heating are continued. If yes, the first heat exchanger (11) is connected to the main pipeline for heating, switching to the indoor heating state.

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