A heat pump clothes dryer with controllable condensing temperature, a system, a control method and a storage medium

Abstract

The present application relates to a kind of controllable condensing temperature heat pump clothes dryer and system, control method, storage medium, the method includes the following steps: judging the current drying stage of drying process;Obtain the condensing temperature adjustment strategy corresponding to current drying stage;Adjust through the condensing temperature adjustment strategy obtained.This application can reasonably control the refrigerant dryness entering the evaporator by the design of double condenser, mixed with two different dryness refrigerant, realize more accurate dryness regulation;At the same time, through the separate control of throttling valve, the condensing pressure can be reasonably designed by the series design of double condenser, more flexible to cope with variable working condition, more efficient and energy saving.

Description

Technical Field

[0001] This invention relates to the field of heat pump dryer technology, and in particular to a heat pump dryer and system with controllable condensation temperature, control method, and storage medium. Background Technology

[0002] A clothes dryer is a household appliance that uses electric heating to instantly evaporate the moisture from washed clothes. It is especially useful in northern winters and in the humid, rainy seasons of the south where clothes are difficult to dry. In addition, clothes dryers are widely used in industrial production to dry fabrics and improve production efficiency.

[0003] In clothes dryers, heat pump technology is the most efficient way to save energy during the drying process, and therefore it has been widely used. Currently, in the drying stage, heat pump dryers dehumidify and cool the evaporator of the heat pump system, processing the hot, humid air at the drum outlet into dry, cool air. This dry air is then heated by the condenser to become the required hot, dry air before entering the drum for drying. As the drying process continues, the inlet state of the heat exchanger in the heat pump system is constantly changing. Conventional fixed-frequency capillary tube systems have poor adjustment capabilities and can only be protected against high-temperature overload by forcibly shutting down the machine, which cannot guarantee continuous and reliable system operation. Summary of the Invention

[0004] In order to achieve the above-mentioned objectives and other advantages of the present invention, a first objective of the present invention is to provide a control method for a heat pump dryer system with controllable condensation temperature, comprising the following steps:

[0005] Determine the current drying stage of the drying process;

[0006] Obtain the condensation temperature adjustment strategy corresponding to the current drying stage;

[0007] Adjustments are made based on the obtained condensation temperature adjustment strategy.

[0008] Furthermore, determining the current drying stage of the drying process includes the following steps:

[0009] Obtain the collected humidity values ​​of the clothing and / or the running time of the drying process;

[0010] Determine whether the collected clothing humidity value and / or the drying process running time have reached the preset value for the later stage of drying;

[0011] Otherwise, the current drying stage of the drying process is determined to be the early drying stage;

[0012] If so, the current drying stage of the drying process is determined to be the later stage of drying.

[0013] Furthermore, the condensation temperature adjustment strategy includes:

[0014] If the current drying stage is the early stage of drying, then control the dryness of the refrigerant entering the evaporator;

[0015] If the current drying stage is the later stage of drying, then control the pressure of the first condenser and the second condenser.

[0016] Furthermore, the adjustment based on the obtained condensation temperature adjustment strategy includes the following steps:

[0017] When the current drying stage of the drying process is the early drying stage, control the first condenser and the second condenser to operate normally;

[0018] When the current drying stage is the later stage of drying, reduce the opening degree of the first throttle valve and increase the opening degree of the second throttle valve.

[0019] Furthermore, the condensation temperature adjustment strategy also includes:

[0020] When the current drying stage of the drying process is the early drying stage, the temperature at the refrigerant inlet of the evaporator is collected;

[0021] The refrigerant dryness is calculated based on the temperature at the refrigerant inlet of the evaporator.

[0022] Determine whether the calculated refrigerant dryness meets the target value;

[0023] Adjust the opening degree of the first and second throttle valves based on the judgment result.

[0024] Furthermore, the adjustment based on the obtained condensation temperature adjustment strategy also includes the following steps:

[0025] When the current drying stage of the drying process is the early drying stage, if the calculated refrigerant dryness does not reach the target value, the opening degree of the first throttle valve is reduced and / or the opening degree of the second throttle valve is increased.

[0026] If the calculated refrigerant dryness reaches the target value, then maintain the opening degree of the first throttle valve and the opening degree of the second throttle valve.

[0027] Furthermore, the condensation temperature adjustment strategy also includes:

[0028] When the current drying stage of the drying process is the later stage of drying, the temperature of the first condenser is collected;

[0029] The temperature of the first condenser is matched with the corresponding pressure value;

[0030] Determine whether the matched pressure value reaches the target value;

[0031] Adjust the opening degree of the first and second throttle valves based on the judgment result;

[0032] The adjustment based on the obtained condensation temperature adjustment strategy also includes the following steps:

[0033] When the current drying stage of the drying process is the later stage of drying, if the matched pressure value does not reach the target value, the opening degree of the first throttle valve and the opening degree of the second throttle valve shall be maintained.

[0034] If the matched pressure value reaches the target value, the opening degree of the first throttle valve is reduced and the opening degree of the second throttle valve is increased.

[0035] A second objective of this invention is to provide a computer-readable storage medium having program instructions stored thereon, which, when executed, implement a control method for a heat pump dryer system with controllable condensation temperature.

[0036] A third objective of this invention is to provide a heat pump dryer system with controllable condensing temperature, comprising: a compressor, a first condenser, a first throttling valve, a second condenser, a second throttling valve, an evaporator, and a controller. The discharge pipe of the compressor is connected to the inlet of the first condenser and the inlet of the second condenser, respectively. The outlet of the first condenser is connected to the inlet of the evaporator via the first throttling valve. The outlet of the second condenser is connected to the inlet of the evaporator via the second throttling valve. The outlet of the evaporator is connected to the suction pipe of the compressor. The controller is used to execute a control method for a heat pump dryer system with controllable condensing temperature.

[0037] The fourth objective of this invention is to provide a heat pump dryer with controllable condensation temperature, comprising a dryer body and a heat pump dryer system with controllable condensation temperature disposed within the dryer body.

[0038] Compared with the prior art, the beneficial effects of the present invention are:

[0039] This invention provides a heat pump dryer and system with controllable condensing temperature, a control method, and a storage medium. By using a dual-condenser design, two refrigerants with different dryness fractions are mixed before entering the evaporator, which can reasonably control the dryness fraction of the refrigerant entering the evaporator and achieve more precise dryness adjustment. At the same time, by adopting a dual-condenser series design and controlling the throttling valve individually, the condensing pressure can be reasonably designed, which can more flexibly cope with changing operating conditions and achieve higher efficiency and energy saving.

[0040] During normal operation, the condensing pressures of the first condenser and the second condenser are different, with the pressure of the first condenser being greater than that of the second condenser. In the early stage of drying, when rapid heating is required, the condensing load of the second condenser is larger, and normal operation is sufficient to achieve heating. In the later stage of drying, the duct temperature is higher, and the overall condensing load is already relatively large. By closing the first throttle valve and opening the second throttle valve, the condensing pressure of the first condenser is unloaded, allowing the entire system to operate continuously without interruption.

[0041] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it according to the contents of the specification, the preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings. Specific embodiments of the present invention are given in detail below with reference to the accompanying drawings. Attached Figure Description

[0042] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0043] Figure 1 This is a schematic diagram of a heat pump dryer system with controllable condensation temperature, as shown in Example 1.

[0044] Figure 2 The control method flow of a heat pump dryer system with controllable condensation temperature is shown in Example 3. Figure 1 ;

[0045] Figure 3 The control method flow of a heat pump dryer system with controllable condensation temperature is shown in Example 3. Figure 2 ;

[0046] Figure 4 This is a schematic diagram of the electronic device in Example 4;

[0047] Figure 5 This is a block diagram of the computer-readable storage medium in Example 5.

[0048] In the attached diagram: 1. Compressor; 2. First condenser; 3. First throttle valve; 4. Second condenser; 5. Second throttle valve; 6. Evaporator; 7. Drum. Detailed Implementation

[0049] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0050] As the heat pump dryer operates, the evaporator inlet status of the heat pump system constantly changes. Conventional fixed-frequency capillary systems have poor adjustment capabilities and can only achieve high-temperature overload protection through forced shutdown, failing to guarantee continuous and reliable system operation. In contrast, this invention achieves rapid temperature rise in the early stages of the drying process through dual condensing pressure control, and unloads the load in the later stages through throttling valve control, ensuring continuous and reliable system operation.

[0051] Example 1

[0052] A heat pump dryer system with controllable condensation temperature, such as Figure 1 As shown, the system includes: a compressor 1, a first condenser 2, a first throttle valve 3, a second condenser 4, a second throttle valve 5, an evaporator 6, and a controller. The discharge pipe of the compressor 1 is connected to the inlet of the first condenser 2 and the inlet of the second condenser 4, respectively. The outlet of the first condenser 2 is connected to the inlet of the evaporator 6 via the first throttle valve 3. The outlet of the second condenser 4 is connected to the inlet of the evaporator 6 via the second throttle valve 5. The outlet of the evaporator 6 is connected to the suction pipe of the compressor 1. The controller is used to execute the control method of the heat pump dryer system with controllable condensing temperature. For a detailed description of the control method of the heat pump dryer system with controllable condensing temperature, please refer to the corresponding description in the following method embodiments.

[0053] The refrigerant circuit consists of compressor 1, first condenser 2, first expansion valve 3, second condenser 4, second expansion valve 5, and evaporator 6. Compressor 1 pressurizes and heats the refrigerant, which is then sent to the first condenser 2 to release heat. The first condenser 2 is connected to the airflow inside the dryer, outputting hot, dry air. The refrigerant enters the first expansion valve 3 from the first condenser 2 and the second expansion valve 5 from the second condenser 4. After passing through both valves, it enters the evaporator 6, where its pressure and temperature rapidly decrease, absorbing heat energy and reaching a temperature below the dew point. The evaporator 6 is connected to the drying airflow, transforming the humid, hot air into dry, cool air. Water vapor from the clothes condenses into small water droplets here and is collected in the condensation tray.

[0054] By using a dual-condenser design, two refrigerants with different dryness fractions are mixed before entering the evaporator, achieving more precise dryness adjustment.

[0055] The first condenser 2, the second condenser 4, and the evaporator 6 form an air circulation loop. The drying fan sends hot air heated by the first condenser 2 into the drum 7. The clothes inside the drum 7 are heated and tumbled, accelerating the evaporation of moisture into water vapor (humid hot air). The drying filter captures lint and debris from the clothes, which then enters the evaporator 6. There, the moisture in the clothes condenses into small droplets, becoming dry, cool air, which continues into the second condenser 4 and then back into the first condenser 2. The water vapor from the clothes is collected in a drip tray. A drain pump pumps the condensate from the drip tray to a higher position, where it is sent to a storage tank. This process is repeated until the humidity sensor determines that the moisture content of the clothes has reached the set target, at which point the drying process ends.

[0056] In the air circulation loop, the dry, cold air from the evaporator 6 outlet enters the second condenser 4 and is initially heated, then reheated by the first condenser 2. This means the inlet air conditions of the first condenser 2 and the second condenser 4 are different: the inlet temperature of the second condenser 4 is low, resulting in low condensing pressure, while the inlet temperature of the first condenser 2 is high, resulting in high condensing pressure. According to the definition of dryness:

[0057]

[0058] Where x is the dryness fraction, q0 is the unit refrigeration capacity, q0 is a constant, and r is the heat of vaporization, which is positively correlated with temperature.

[0059] According to the above definition formula for dryness, the dryness of the second condenser 4 with lower condensing pressure is lower than that of the first condenser 2.

[0060] During normal operation, the condensing pressures of the first condenser 2 and the second condenser 4 are different, with the first condenser 2 having a higher condensing pressure than the second condenser 4. In the early stages of drying, when rapid temperature increase is required, the second condenser 4 experiences a higher condensing load, which can be achieved through normal operation. In the later stages of drying, the duct temperature is higher, resulting in a larger overall condensing load. By closing the first throttle valve 3 and opening the second throttle valve 5, the condensing pressure of the first condenser 2 is relieved, allowing the entire system to operate continuously without interruption.

[0061] The present invention provides a heat pump dryer system with controllable condensing temperature. In the early stage, it achieves rapid heating through dual condensing pressure control, and in the later stage, it achieves load unloading through dual throttling valve control, which can ensure continuous and reliable operation of the system.

[0062] Example 2

[0063] A heat pump dryer with controllable condensation temperature includes a dryer body and a heat pump dryer system with controllable condensation temperature disposed within the dryer body. A detailed description of the heat pump dryer system with controllable condensation temperature can be found in the corresponding description in the above system embodiments, and will not be repeated here.

[0064] Example 3

[0065] Example 1 describes a control method for a heat pump dryer system with controllable condensation temperature, such as... Figure 2 As shown, it includes the following steps:

[0066] To meet the condensation temperature requirements at different stages of the drying process, it is first necessary to determine the current drying stage; specifically, such as... Figure 3 As shown, it includes the following steps:

[0067] Obtain the collected humidity values ​​of the clothing and / or the running time of the drying process;

[0068] When the only parameter to be judged is the humidity value of the clothes, it is determined whether the collected humidity value of the clothes has reached the preset humidity value in the later stage of drying.

[0069] Otherwise, the current drying stage of the drying process is determined to be the early drying stage;

[0070] If so, the current drying stage of the drying process is determined to be the later stage of drying.

[0071] When the only parameter to be judged is the running time of the drying process, the judgment is made as to whether the running time of the drying process has reached the start time of the later stage of drying.

[0072] Otherwise, the current drying stage of the drying process is determined to be the early drying stage;

[0073] If so, the current drying stage of the drying process is determined to be the later stage of drying.

[0074] When the parameters to be judged include the humidity value of the clothes and the running time of the drying process, it is determined whether the collected humidity value of the clothes and the running time of the drying process have both reached the preset value for the later stage of drying.

[0075] Otherwise, the current drying stage of the drying process is determined to be the early drying stage;

[0076] If so, the current drying stage of the drying process is determined to be the later stage of drying.

[0077] Obtain the condensing temperature adjustment strategy corresponding to the current drying stage. Since the second condenser has a high condensing load during the early drying stage when rapid temperature rise is required, normal operation is sufficient to achieve the desired temperature increase. Therefore, the drying strategy for the early drying stage is to control the refrigerant dryness entering the evaporator.

[0078] In the later stages of drying, the duct temperature is high, and the overall condensation load is already relatively large. This can be addressed by closing the first throttle valve slightly and opening the second throttle valve more fully to relieve the condensing pressure in the first condenser, allowing the entire system to operate continuously. Therefore, the drying strategy for the later stages of drying involves controlling the pressure of both the first and second condensers.

[0079] Adjustments are made based on the obtained condensation temperature adjustment strategy; among which,

[0080] When the current drying stage of the drying process is the early drying stage, control the first condenser and the second condenser to operate normally;

[0081] When the current drying stage is the later stage of drying, reduce the opening degree of the first throttle valve and increase the opening degree of the second throttle valve.

[0082] Because the dry, cold air exiting the evaporator first enters the second condenser for initial heating, and then passes through the first condenser for further heating, the inlet air conditions of the first and second condensers are inconsistent. The second condenser has a lower inlet temperature and lower condensing pressure, while the first condenser has a higher inlet temperature and higher condensing pressure. According to the definition of dryness fraction, the dryness fraction of the second condenser, with its lower condensing pressure, is lower than that of the first condenser. This invention, through a dual-condenser design, mixes two refrigerants with different dryness fractions before they enter the evaporator, achieving more precise dryness fraction regulation.

[0083] In order to reasonably control the dryness of the refrigerant entering the evaporator, when the current drying stage of the drying process is the early drying stage, the temperature at the refrigerant inlet of the evaporator is collected;

[0084] The refrigerant dryness is calculated based on the temperature at the refrigerant inlet of the evaporator.

[0085] Determine whether the calculated refrigerant dryness meets the target value;

[0086] Adjust the opening degree of the first and second throttle valves based on the judgment result.

[0087] In order to ensure that the efficiency of the refrigerant side in the evaporator is high enough, the dryness of the refrigerant in the evaporator must be minimized so that most of the effective heat exchange area is in contact with saturated or even subcooled refrigerant, so as to keep most of the refrigerant side area in the continuously vigorous boiling heat exchange region.

[0088] In actual heat pump system operation, in order to achieve the goal of high-efficiency and energy-saving operation, the energy-saving level of the dryer is improved.

[0089] When the current drying stage of the drying process is the early drying stage, if the calculated refrigerant dryness does not reach the target value, the opening degree of the first throttle valve is reduced and / or the opening degree of the second throttle valve is increased to reduce the refrigerant dryness entering the evaporator after the two refrigerants with different dryness are mixed.

[0090] If the calculated refrigerant dryness reaches the target value, then maintain the opening degree of the first throttle valve and the opening degree of the second throttle valve.

[0091] As the drying process proceeds, the evaporator inlet state of the heat pump system constantly changes. Conventional fixed-frequency capillary systems have poor adjustment capabilities and can only achieve high-temperature overload protection through forced shutdown. To ensure continuous and reliable system operation, this invention achieves load unloading through the control of a first throttling valve and a second throttling valve.

[0092] Because the dry, cold air from the evaporator outlet first enters the second condenser for initial heating, and then passes through the first condenser for further heating, the inlet air conditions of the first and second condensers are inconsistent. The second condenser has a lower inlet temperature and lower condensing pressure, while the first condenser has a higher inlet temperature and higher condensing pressure. By rationally designing the condensing pressure and unloading the condensing pressure of the first condenser, the entire system can operate continuously and without interruption, resulting in higher efficiency and energy savings.

[0093] When the current drying stage of the drying process is the later stage of drying, the temperature of the first condenser is collected;

[0094] Match the collected temperature of the first condenser with the corresponding pressure value; for example, match the collected temperature of the first condenser with the corresponding pressure value using a temperature-pressure lookup table.

[0095] Determine whether the matched pressure value reaches the target value;

[0096] Adjust the opening degree of the first and second throttle valves based on the judgment result;

[0097] To avoid the first condenser from overheating, the only way to protect against high temperature overload is to force a shutdown.

[0098] When the current drying stage of the drying process is the later stage of drying, if the matched pressure value does not reach the target value, the opening degree of the first throttle valve and the opening degree of the second throttle valve shall be maintained.

[0099] If the matched pressure value reaches the target value, the opening degree of the first throttle valve is reduced and the opening degree of the second throttle valve is increased to unload the load of the first condenser and ensure the continuous and reliable operation of the system.

[0100] Example 4

[0101] An electronic device 200, such as Figure 4 As shown, the system includes, but is not limited to: a memory 201 storing program code; and a processor 202 connected to the memory, which, when the program code is executed by the processor, implements a control method for a heat pump dryer system with controllable condensation temperature. For a detailed description of the method, please refer to the corresponding description in the above method embodiments, which will not be repeated here.

[0102] Example 5

[0103] A computer-readable storage medium, such as Figure 5As shown, it stores program instructions, which, when executed, implement a control method for a heat pump dryer system with controllable condensation temperature. For a detailed description of the method, please refer to the corresponding description in the above method embodiments; it will not be repeated here.

[0104] Example 6

[0105] A computer program product includes a computer program / instructions that, when executed by a processor, implement a control method for a heat pump dryer system with controllable condensation temperature. A detailed description of the method can be found in the corresponding descriptions in the above-described method embodiments, and will not be repeated here.

[0106] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0107] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0108] The above are merely embodiments of this specification and are not intended to limit the scope of the one or more embodiments herein. For those skilled in the art, various modifications and variations can be made to the one or more embodiments of this specification. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of the one or more embodiments of this specification should be included within the scope of the claims of the one or more embodiments of this specification.

Claims

1. A control method for a heat pump dryer system with controllable condensation temperature, characterized in that, The heat pump dryer system includes a compressor, a first condenser, a first expansion valve, a second condenser, a second expansion valve, and an evaporator. The outlet of the first condenser is connected to the inlet of the evaporator via the first expansion valve, and the outlet of the second condenser is connected to the inlet of the evaporator via the second expansion valve. The system includes the following steps: Determine the current drying stage of the drying process; Obtain the condensation temperature adjustment strategy corresponding to the current drying stage; Adjustments are made based on the obtained condensation temperature adjustment strategy; Determining the current drying stage of the drying process includes the following steps: Obtain the collected humidity values ​​of the clothing and / or the running time of the drying process; Determine whether the collected clothing humidity value and / or the drying process running time have reached the preset value for the later stage of drying; Otherwise, the current drying stage of the drying process is determined to be the early drying stage; If so, the current drying stage of the drying process is determined to be the later stage of drying; The condensation temperature adjustment strategy includes: If the current drying stage is the early stage of drying, then control the dryness of the refrigerant entering the evaporator; If the current drying stage is the later stage of drying, then control the pressure of the first condenser and the second condenser; The adjustment based on the obtained condensation temperature adjustment strategy includes the following steps: When the current drying stage of the drying process is the early drying stage, control the first condenser and the second condenser to operate normally; When the current drying stage is the later stage of drying, reduce the opening degree of the first throttle valve and increase the opening degree of the second throttle valve.

2. The control method for a heat pump dryer system with controllable condensation temperature according to claim 1, characterized in that, The condensation temperature adjustment strategy also includes: When the current drying stage of the drying process is the early drying stage, the temperature at the refrigerant inlet of the evaporator is collected; The refrigerant dryness is calculated based on the temperature at the refrigerant inlet of the evaporator. Determine whether the calculated refrigerant dryness meets the target value; Adjust the opening degree of the first and second throttle valves based on the judgment result.

3. The control method for a heat pump dryer system with controllable condensation temperature according to claim 2, characterized in that, The adjustment based on the obtained condensation temperature adjustment strategy also includes the following steps: When the current drying stage of the drying process is the early drying stage, if the calculated refrigerant dryness does not reach the target value, the opening degree of the first throttle valve is reduced and / or the opening degree of the second throttle valve is increased. If the calculated refrigerant dryness reaches the target value, then maintain the opening degree of the first throttle valve and the opening degree of the second throttle valve.

4. The control method for a heat pump dryer system with controllable condensation temperature according to claim 1, characterized in that, The condensation temperature adjustment strategy also includes: When the current drying stage of the drying process is the later stage of drying, the temperature of the first condenser is collected; The temperature of the first condenser is matched with the corresponding pressure value; Determine whether the matched pressure value reaches the target value; Adjust the opening degree of the first and second throttle valves based on the judgment result; The adjustment based on the obtained condensation temperature adjustment strategy also includes the following steps: When the current drying stage of the drying process is the later stage of drying, if the matched pressure value does not reach the target value, the opening degree of the first throttle valve and the opening degree of the second throttle valve shall be maintained. If the matched pressure value reaches the target value, the opening degree of the first throttle valve is reduced and the opening degree of the second throttle valve is increased.

5. A computer-readable storage medium, characterized in that, It stores program instructions that, when executed, implement the method as described in any one of claims 1 to 4.

6. A heat pump dryer system with controllable condensation temperature, characterized in that, include: The system comprises a compressor, a first condenser, a first throttle valve, a second condenser, a second throttle valve, an evaporator, and a controller. The discharge pipe of the compressor is connected to the inlet of the first condenser and the inlet of the second condenser, respectively. The outlet of the first condenser is connected to the inlet of the evaporator via the first throttle valve. The outlet of the second condenser is connected to the inlet of the evaporator via the second throttle valve. The outlet of the evaporator is connected to the suction pipe of the compressor. The controller is used to execute a control method for a heat pump dryer system with controllable condensing temperature as described in any one of claims 1 to 4.

7. A heat pump dryer with controllable condensation temperature, characterized in that: The dryer includes a dryer body and a heat pump dryer system with controllable condensation temperature as described in claim 6, which is disposed within the dryer body.

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