A heat pump unit

Abstract

The present application relates to a kind of heat pump units, including improved automatic decision-making heat pump unit carries out refrigeration mode or heating mode or standby mode method, the controller of heat pump unit obtains and stores the ambient temperature collected by temperature sensor in real time, calculate the average ambient temperature of short period, medium-long period and long period, and the temperature difference of real-time ambient temperature, average ambient temperature respectively with the heating start point temperature, refrigeration start point temperature of heat pump unit set is compared with the corresponding heating temperature difference threshold or refrigeration temperature difference threshold and judges, and then control the switching of the refrigeration mode, heating mode, standby mode of heat pump unit.This automatic decision-making method can effectively avoid the problem that heat pump unit repeatedly switches refrigeration mode, heating mode when ambient temperature fluctuates around the set refrigeration, heating start point temperature, can prolong the service life of compressor, evaporator, condenser.

Description

Technical Field

[0001] This invention relates to the field of heat pumps, and more particularly to a heat pump unit. Background Technology

[0002] With global warming and the improvement of living standards in my country, more and more families are demanding a constant temperature in their living environment throughout the year. Because heat pump units are highly efficient and energy-saving devices that can transfer heat from a low-temperature heat source to a high-temperature heat source for utilization, an increasing number of families are choosing heat pump units to achieve this goal.

[0003] Currently, heat pump units on the market generally automatically determine heating and cooling modes based on ambient temperature to maintain a constant temperature in the living environment. When the ambient temperature changes from high to low, the heat pump unit first decides on the cooling mode, then the heating mode; when the ambient temperature changes from low to high, the heat pump unit first decides on the heating mode, then the cooling mode. However, when the ambient temperature fluctuates at the boundary between heating and cooling, the problem of repeatedly switching between cooling and heating modes occurs. For example, if the boundary temperature for determining cooling and heating is 25°C, when the ambient temperature changes between 24°C and 26°C, the heat pump unit will decide on cooling mode at 26°C and heating mode at 24°C.

[0004] The current automatic mode decision-making method causes heat pump units to frequently switch between cooling and heating modes. The repeated start-up, shutdown, and switching between cooling and heating modes of the heat pump units will cause repeated thermal shocks to the evaporator and condenser, affecting the reliability and lifespan of the heat pump. Summary of the Invention

[0005] Based on this, the purpose of the present invention is to provide a heat pump unit that provides a stable automatic mode decision-making method when the ambient temperature fluctuates, thereby avoiding the problems of repeated start-up and shutdown of the heat pump unit and frequent switching between hot and cold modes in the evaporator and condenser.

[0006] A heat pump unit includes a compressor, a four-way valve, a condenser, a throttling valve, and an evaporator connected sequentially via a refrigerant circulation pipeline, a temperature sensor, and a controller electrically and / or communicatively connected to the compressor, the four-way valve, and the temperature sensor. The controller controls the switching between cooling mode, heating mode, and standby mode of the heat pump unit using the following method:

[0007] The system acquires the current ambient temperature and the short-term average ambient temperature tracing back from the current moment in real time, and compares the short-term average ambient temperature with preset heating start-up temperatures and cooling start-up temperatures.

[0008] If the short-term average ambient temperature is greater than or equal to the cooling start-up temperature, then the medium-to-long-term average ambient temperature traced back from the current time is obtained, and the temperature difference between the current ambient temperature, the medium-to-long-term average ambient temperature and the cooling start-up temperature is calculated in turn. Each temperature difference value is then compared with the set cooling temperature difference threshold, and a cooling signal or a standby signal is output based on the comparison result.

[0009] If the average ambient temperature over a short period of time is lower than the cooling start-up temperature but higher than the heating start-up temperature, then a standby signal will be output.

[0010] If the short-term average ambient temperature is less than or equal to the heating start-up temperature, the medium-to-long-term average ambient temperature is obtained, and the temperature difference between the heating start-up temperature and the current ambient temperature and the medium-to-long-term average ambient temperature are calculated in turn. Each temperature difference value is then compared with the set heating temperature difference threshold, and a heating signal or a standby signal is output based on the comparison result.

[0011] Compared with existing technologies, the heat pump unit of this invention collects and calculates the average ambient temperature over a period of time. It compares this average ambient temperature with preset heating and cooling start-up temperatures. Furthermore, it compares the temperature difference between the average ambient temperature and the heating or cooling start-up temperatures with a set cooling or heating temperature difference threshold before controlling the heat pump unit to switch between cooling, heating, and standby modes. This automatic switching control method effectively solves the problem of frequent switching between cooling and heating modes caused by fluctuations in ambient temperature around the set heating and cooling start-up temperatures. It also solves the problems of repeated start-up and shutdown and frequent switching between hot and cold modes in the evaporator and condenser in existing technologies, improving the stability of the compressor, evaporator, and condenser, and extending their lifespan.

[0012] Furthermore, when the short-term average ambient temperature is greater than or equal to the cooling start-up temperature, the controller controls the heat pump unit to switch to cooling mode or standby mode using the following method:

[0013] Based on the current ambient temperature, calculate the temperature difference between the current ambient temperature and the cooling start-up temperature. This temperature difference is defined as a first temperature difference, and the first temperature difference is compared with a first cooling temperature difference threshold.

[0014] If the first temperature difference is greater than or equal to the first cooling temperature difference threshold, then a cooling signal is output;

[0015] If the first temperature difference is less than the first cooling temperature difference threshold, then the average ambient temperature over a medium-to-long-term period is further obtained, and the temperature difference between the average ambient temperature over a medium-to-long-term period and the cooling start-up temperature is calculated. This temperature difference is the second temperature difference, and the second temperature difference is compared with the second cooling temperature difference threshold.

[0016] If the second temperature difference is greater than or equal to the second cooling temperature difference threshold, a cooling signal is output.

[0017] If the second temperature difference is less than the second cooling temperature difference threshold, a standby signal is output.

[0018] Furthermore, when the short-term average ambient temperature is less than or equal to the heating start-up temperature, the controller controls the heat pump unit to switch to heating mode or standby mode using the following method:

[0019] Based on the current ambient temperature, the temperature difference between the heating start-up temperature and the current ambient temperature is calculated. This temperature difference is the fourth temperature difference, and it is compared with the first heating temperature difference threshold.

[0020] If the fourth temperature difference is greater than or equal to the first heating temperature difference threshold, then output a heating signal;

[0021] If the fourth temperature difference is less than the first heating temperature difference threshold, then the average ambient temperature over a medium-to-long-term period is further obtained, and the temperature difference between the heating start-up temperature and the average ambient temperature over a medium-to-long-term period is calculated. This temperature difference is the fifth temperature difference, and the fifth temperature difference is compared with the second heating temperature difference threshold.

[0022] If the fifth temperature difference is greater than or equal to the second heating temperature difference threshold, then a heating signal is output;

[0023] If the fifth temperature difference is less than the second heating temperature difference threshold, a standby signal will be output.

[0024] Furthermore, the first cooling temperature difference threshold range is 5–6℃; the second cooling temperature difference threshold range is 3–4℃; the first heating temperature difference threshold range is 5–6℃; and the second heating temperature difference threshold range is 3–4℃.

[0025] Furthermore, the temperature acquisition and calculation time for the short-term average ambient temperature is 3 to 5 minutes, and the temperature acquisition and calculation time for the medium-to-long-term average ambient temperature is 1 to 2 hours.

[0026] To better understand and implement this invention, the following detailed description is provided in conjunction with the accompanying drawings. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of a heat pump unit according to an embodiment of the present invention;

[0028] Figure 2This is a control flowchart for the automatic switching of the operating mode of a heat pump unit according to an embodiment of the present invention. Detailed Implementation

[0029] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings of the embodiments of the present invention.

[0030] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to limit the embodiments of this application. The singular forms “a,” “the,” and “the” used in the embodiments of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that, unless otherwise stated, “a plurality” means two or more; and the term “and / or” as used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0031] In the following description, when referring to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. In the description of this application, it should be understood that the terms "first," "second," "third," etc., are used only for distinction and not to describe a specific order or sequence, nor should they be construed as indicating or implying relative importance. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0032] When a heat pump unit automatically controls itself based on monitored ambient temperature and set cooling / heating thresholds, if the ambient temperature fluctuates around these thresholds, the heat pump unit may repeatedly switch between cooling and heating modes. This causes the evaporator and condenser to be subjected to repeated hot and cold shocks, affecting their reliability and lifespan. To address this issue, this invention proposes a heat pump unit with an improved method for automatically deciding whether to switch to cooling, heating, or standby mode. The controller of the heat pump unit acquires and stores the ambient temperature collected by the temperature sensor in real time, calculates the average ambient temperature over short, medium, and long periods, and compares the real-time and average ambient temperatures with the temperature differences between the set heating and cooling start-up points and the corresponding heating or cooling temperature difference thresholds. This comparison then controls the switching between the cooling, heating, and standby modes of the heat pump unit. This automatic decision-making method can effectively avoid the problem of heat pump units repeatedly switching between cooling and heating modes when the ambient temperature fluctuates around the set cooling and heating start-up temperature, thus extending the service life of the compressor, evaporator, and condenser.

[0033] For specific implementation details, please refer to [link / reference]. Figure 1 The heat pump unit proposed in this invention includes a compressor 10, a four-way valve 20, a condenser 30, a throttle valve 40, an evaporator 50, a temperature sensor 60, a controller (not shown), and other auxiliary pipes. The compressor 10, four-way valve 20, condenser 30, throttle valve 40, and evaporator 50 are sequentially connected in a refrigerant pipeline; the controller is electrically and / or communicatively connected to the compressor 10, four-way valve 20, and temperature sensor 60.

[0034] The temperature sensor 60 is used to collect ambient temperature signals and transmit them to the controller. The collection interval can be set according to the environmental conditions of the heat pump unit; it is recommended to collect the ambient temperature every 30 seconds or every minute. The temperature sensor 60 can be installed on the outside of the evaporator 50 or on the casing of the heat pump unit; this application does not impose any restrictions.

[0035] The controller receives the temperature signal transmitted by the temperature sensor 60.

[0036] The controller also includes a storage unit and a processing unit. The storage unit is used to store the heating start-up temperature T set by the heat pump unit. H-auto Refrigeration start-up temperature T C-auto Several cooling temperature difference thresholds ΔT CTV and several heating temperature difference thresholds ΔT HTV The ambient temperature collected by the temperature sensor 60 at each time point. The processing unit is used to calculate the average ambient temperature collected at each time point over short, medium-long, and long time periods. And according to the preset heating start-up temperature T H-auto Refrigeration start-up temperature T C-auto The ambient temperature at the current moment of collection. The system judges the corresponding temperature difference threshold and outputs cooling, heating, and standby signals to the compressor 10 and the four-way valve 20, thereby controlling the heat pump unit to switch between cooling mode, heating mode, and standby mode.

[0037] Specifically, the controller controls the heat pump unit to switch between cooling mode, heating mode, and standby mode through the following steps.

[0038] S10 acquires the current ambient temperature and the short-term average ambient temperature traced back from the current time in real time, compares the short-term average ambient temperature with the preset cooling start point temperature and heating start point temperature, and proceeds to determine cooling, heating, or standby based on the comparison result.

[0039] This step includes the following sub-steps.

[0040] S11 obtains the current ambient temperature in real time. and the short-term average ambient temperature tracing back from the current time. and the short-term average ambient temperature Compared with the preset cooling start-up temperature T C-auto Comparison:

[0041] If the short-term average ambient temperature Greater than or equal to the cooling start-up temperature T C-auto Then proceed to step S20;

[0042] If the short-term average ambient temperature Less than the cooling start-up temperature T C-auto Then proceed to step S12;

[0043] S12 further calculates the short-term average ambient temperature With the preset heating start-up temperature T H-auto Comparison:

[0044] If the short-term average ambient temperature Greater than the heating start-up temperature T H-auto If so, then a standby signal will be output;

[0045] If the short-term average ambient temperature Less than or equal to the heating start-up temperature T H-auto Then proceed to step S30.

[0046] The short-term average ambient temperature The time calculation point is to trace back a short period of time from the current moment, and calculate the average ambient temperature using all the ambient temperatures collected by the temperature sensor 60 within this time period. This time period is preferably 3 to 5 minutes.

[0047] In another embodiment, step S10 includes the following sub-steps.

[0048] S`11 obtains the current ambient temperature in real time. and the short-term average ambient temperature tracing back from the current time. and the short-term average ambient temperature With the preset heating start-up temperature T H-auto Comparison:

[0049] If the short-term average ambient temperature Less than or equal to the heating start-up temperature T H-auto Then proceed to step S30;

[0050] If the short-term average ambient temperature Greater than the heating start-up temperature TH-auto Then proceed to step S`12;

[0051] S`12 further includes the short-term average ambient temperature Compared with the preset cooling start-up temperature T C-auto Comparison:

[0052] If the short-term average ambient temperature Less than the cooling start-up temperature T C-auto If so, then a standby signal will be output;

[0053] If the short-term average ambient temperature Greater than or equal to the cooling start-up temperature T C-auto Then proceed to step S20.

[0054] This invention does not limit whether the controller first compares the short-term average ambient temperature with the cooling start-up temperature or first compares the short-term average temperature with the heating start-up temperature. As long as the logic is set to satisfy the condition that the controller can continue to output a cooling signal or a heating signal after comparing the short-term average temperature with the cooling start-up temperature and the heating start-up temperature.

[0055] S20 obtains the average ambient temperature over a medium-to-long-term period, tracing back from the current time. and long-term average ambient temperature And calculate the ambient temperature at the current moment in turn. Medium- to long-term average ambient temperature and long-term average ambient temperature With cooling start-up temperature T C-auto The temperature difference value is calculated, and each temperature difference value is compared with the set cooling temperature difference threshold value in turn. Based on the comparison result, a cooling signal or a standby signal is output.

[0056] Among them, the average ambient temperature over the medium to long period The time calculation point is a period of time preceding the current moment, and the average ambient temperature is calculated using all ambient temperatures collected by the temperature sensor 60 within this time period. This time period is preferably 1-2 hours. The long-term average ambient temperature... The time calculation point is to trace back a relatively long period of time from the current moment, and to calculate the average ambient temperature using all the ambient temperatures collected by the temperature sensor 60 within this time period. This time period is preferably 22 to 24 hours.

[0057] This step includes the following sub-steps.

[0058] S21 obtains the current ambient temperature. Calculate the ambient temperature at the current moment. With cooling start-up temperature TC-auto The temperature difference value, wherein the temperature difference value is a first temperature difference ΔT1, and the first temperature difference ΔT1 is compared with a first cooling temperature difference threshold ΔT 1-CTV Comparison:

[0059] If the first temperature difference ΔT1 is greater than or equal to the first cooling temperature difference threshold ΔT 1-CTV If so, a cooling signal will be output;

[0060] If the first temperature difference ΔT1 is less than the first cooling temperature difference threshold ΔT 1-CTV Then proceed to step S22.

[0061] Specifically, the first temperature difference threshold ΔT 1-TV The preferred temperature is 5℃~6℃.

[0062] S22 further obtains the average ambient temperature over a medium-to-long-term period, tracing back from the current time. Calculate the average ambient temperature over medium to long periods With cooling start-up temperature T C-auto The temperature difference value, wherein the temperature difference value is the second temperature difference ΔT2, and the second temperature difference ΔT2 is compared with the second cooling temperature difference threshold ΔT 2-CTV Comparison:

[0063] If the second temperature difference ΔT2 is greater than or equal to the second cooling temperature difference threshold ΔT 2-CTV If so, a cooling signal will be output;

[0064] If the second temperature difference ΔT2 is less than the second cooling temperature difference threshold ΔT 2-CTV Then proceed to step S23.

[0065] Specifically, the second temperature difference threshold ΔT 2-TV The preferred temperature is 3℃~4℃.

[0066] S23 further obtains the long-term average ambient temperature tracing back from the current moment. Calculate the long-term average ambient temperature With cooling start-up temperature T C-auto The temperature difference value, wherein the temperature difference value is the third temperature difference ΔT3, and the third temperature difference ΔT3 is compared with the third cooling temperature difference threshold ΔT 3-CTV Comparison:

[0067] If the third temperature difference ΔT3 is greater than or equal to the third cooling temperature difference threshold ΔT 3-CTV If so, a cooling signal will be output;

[0068] If the third temperature difference ΔT3 is less than the third cooling temperature difference threshold ΔT 3-CTV If so, a standby signal will be output.

[0069] Specifically, the third temperature difference threshold ΔT 3-TVThe preferred temperature is 1℃~2℃.

[0070] S30 Obtains the average ambient temperature over the medium-to-long-term period. and long-term average ambient temperature And calculate the heating start-up temperature T in sequence. H-auto With the current ambient temperature Medium- to long-term average ambient temperature and long-term average ambient temperature The temperature difference value is calculated and compared with the set heating temperature difference threshold value in turn. Based on the comparison result, a heating signal or a standby signal is output.

[0071] This step includes the following sub-steps.

[0072] S31 obtains the current ambient temperature. Calculate the heating start-up temperature T H-auto With the current ambient temperature The temperature difference value, wherein the temperature difference value is the fourth temperature difference ΔT4, and the fourth temperature difference ΔT4 is compared with the first heating temperature difference threshold ΔT 1-HTV Comparison:

[0073] If the fourth temperature difference ΔT4 is greater than or equal to the first heating temperature difference threshold ΔT 1-HTV If so, a heating signal will be output;

[0074] If the fourth temperature difference ΔT4 is less than the first heating temperature difference threshold ΔT 1-HTV Then proceed to step S32.

[0075] Specifically, the first heating temperature difference threshold ΔT 1-HTV It can be compared with the first cooling temperature difference threshold ΔT 1-CTV The temperature can be set to be the same or different, preferably 5℃~6℃.

[0076] S32 further obtains the average ambient temperature over medium and long periods. Calculate the heating start-up temperature T H-auto Compared with the average ambient temperature over medium and long periods The temperature difference value, wherein the temperature difference value is the fifth temperature difference ΔT5, and the fifth temperature difference ΔT5 is compared with the second heating temperature difference threshold ΔT 2-HTV Comparison:

[0077] If the fifth temperature difference ΔT5 is greater than or equal to the second heating temperature difference threshold ΔT 2-HTV If so, a heating signal will be output;

[0078] If the fifth temperature difference ΔT5 is less than the second heating temperature difference threshold ΔT 2-HTV Then proceed to step S33.

[0079] Specifically, the second heating temperature difference threshold ΔT 2-HTV It can be compared with the second cooling temperature difference threshold ΔT 2-CTV The temperature can be set to be the same or different, preferably 3℃~4℃.

[0080] S33 further obtains long-term average ambient temperature Calculate the heating start-up temperature T H-auto With long-term average ambient temperature The temperature difference value, wherein the temperature difference value is the sixth temperature difference ΔT6, and the sixth temperature difference ΔT6 is compared with the third heating temperature difference threshold ΔT 3-HTV Comparison:

[0081] If the sixth temperature difference ΔT6 is greater than or equal to the third heating temperature difference threshold ΔT 3-HTV If so, a heating signal will be output;

[0082] If the sixth temperature difference ΔT6 is less than the third heating temperature difference threshold ΔT 3-HTV If so, a standby signal will be output.

[0083] Specifically, the third heating temperature difference threshold ΔT 3-HTV It can be compared with the third cooling temperature difference threshold ΔT 3-CTV The temperature can be set to be the same or different, preferably 1℃~2℃.

[0084] The following example illustrates the setting of the heating start-up temperature T. H-auto =25℃, cooling start-up temperature T C-auto =20℃; the first cooling temperature difference threshold is equal to the first heating temperature difference threshold, set to 5℃; the second cooling temperature difference threshold is equal to the second heating temperature difference threshold, set to 3℃; the third cooling temperature difference threshold is equal to the third heating temperature difference threshold, set to 1℃. The current ambient temperature is 29℃, and the short-term average ambient temperature is calculated. Medium- to long-term average ambient temperature Long-term average ambient temperature According to step S10, the short-term average ambient temperature Greater than the heating start-up temperature T H-auto =25℃, execute step S20; at this time, the current ambient temperature is 29℃ and the heating start-up temperature T H-auto The temperature difference of 25℃ is 4℃, which is less than the first cooling temperature difference threshold of 5℃; therefore, the average ambient temperature over a medium-to-long-term period needs to be used. At the heating start-up temperature T H-auto If the temperature difference of 25℃ is 3℃, further judgment is made. The obtained temperature difference value of 3℃ is equal to the second refrigeration temperature difference threshold of 3℃. At this time, the controller outputs a refrigeration signal to control the compressor and four-way valve to operate in refrigeration mode.

[0085] The heat pump unit of the present invention adopts an improved method of automatically deciding whether to switch between cooling mode, heating mode, or standby mode. This effectively avoids the problem of the heat pump unit repeatedly switching between cooling and heating modes when the ambient temperature fluctuates around the set cooling and heating start-up temperature, and can extend the service life of the compressor, evaporator, and condenser.

[0086] The embodiments described above are merely examples of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and the present invention also intends to include these modifications and variations.

Claims

1. A heat pump unit, comprising a compressor, a four-way valve, a condenser, a throttling valve, and an evaporator connected sequentially via a refrigerant circulation pipeline, a temperature sensor, and a controller electrically and / or communicatively connected to the compressor, the four-way valve, and the temperature sensor, characterized in that, The controller controls the switching of the heat pump unit's cooling mode, heating mode, and standby mode using the following method: The system acquires the current ambient temperature and the short-term average ambient temperature tracing back from the current moment in real time, and compares the short-term average ambient temperature with preset heating start-up temperatures and cooling start-up temperatures. If the short-term average ambient temperature is greater than or equal to the cooling start-up temperature, then the medium-to-long-term average ambient temperature traced back from the current moment is obtained; the temperature difference between the current ambient temperature and the cooling start-up temperature is calculated, and this temperature difference is defined as a first temperature difference. The first temperature difference is then compared with a first cooling temperature difference threshold. If the first temperature difference is greater than or equal to the first cooling temperature difference threshold, then a cooling signal is output; If the first temperature difference is less than the first cooling temperature difference threshold, then the average ambient temperature over a medium-to-long-term period is further obtained, and the temperature difference between the average ambient temperature over a medium-to-long-term period and the cooling start-up temperature is calculated. This temperature difference is the second temperature difference, and the second temperature difference is compared with the second cooling temperature difference threshold. If the second temperature difference is greater than or equal to the second cooling temperature difference threshold, a cooling signal is output. If the second temperature difference is less than the second cooling temperature difference threshold, a standby signal is output. If the average ambient temperature over a short period of time is lower than the cooling start-up temperature but higher than the heating start-up temperature, then a standby signal will be output. If the short-term average ambient temperature is less than or equal to the heating start-up temperature, then the medium-to-long-term average ambient temperature is obtained; the temperature difference between the heating start-up temperature and the current ambient temperature is calculated, and this temperature difference is the fourth temperature difference, which is then compared with the first heating temperature difference threshold. If the fourth temperature difference is greater than or equal to the first heating temperature difference threshold, then output a heating signal; If the fourth temperature difference is less than the first heating temperature difference threshold, then the average ambient temperature over a medium-to-long-term period is further obtained, and the temperature difference between the heating start-up temperature and the average ambient temperature over a medium-to-long-term period is calculated. This temperature difference is the fifth temperature difference, and the fifth temperature difference is compared with the second heating temperature difference threshold. If the fifth temperature difference is greater than or equal to the second heating temperature difference threshold, then a heating signal is output; If the fifth temperature difference is less than the second heating temperature difference threshold, a standby signal will be output.

2. The heat pump unit according to claim 1, characterized in that, The first cooling temperature difference threshold range is 5~6℃; the second cooling temperature difference threshold range is 3~4℃; the first heating temperature difference threshold range is 5~6℃; and the second heating temperature difference threshold range is 3~4℃.

3. The heat pump unit according to claim 1, characterized in that, The temperature acquisition and calculation time for the short-term average ambient temperature is 3 to 5 minutes, and the temperature acquisition and calculation time for the medium-to-long-term average ambient temperature is 1 to 2 hours.

4. The heat pump unit according to any one of claims 1-3, characterized in that, When comparing the short-term average ambient temperature with the preset heating start-up temperature and cooling start-up temperature, the method also includes obtaining the long-term average ambient temperature traced back from the current moment. Specifically: If the short-term average ambient temperature is greater than or equal to the cooling start-up temperature, then continue to acquire the medium-to-long-term average ambient temperature and the long-term average ambient temperature traced back from the current time, and calculate the temperature difference between the current ambient temperature, the medium-to-long-term average ambient temperature, the long-term average ambient temperature and the cooling start-up temperature respectively, and compare each temperature difference value with the set cooling temperature difference threshold respectively, and output a cooling signal or a standby signal according to the comparison result; If the short-term average ambient temperature is less than or equal to the heating start-up temperature, then the medium-to-long-term average ambient temperature and the long-term average ambient temperature are obtained, and the temperature difference between the heating start-up temperature and the current ambient temperature, the medium-to-long-term average ambient temperature, and the long-term average ambient temperature are calculated in turn. Each temperature difference value is then compared with the set heating temperature difference threshold, and a heating signal or a standby signal is output based on the comparison result.

5. The heat pump unit according to claim 4, characterized in that, When the short-term average ambient temperature is greater than or equal to the cooling start-up temperature, the controller controls the heat pump unit to switch to cooling mode or standby mode using the following method: Based on the current ambient temperature, calculate the temperature difference between the current ambient temperature and the cooling start-up temperature. This temperature difference is defined as a first temperature difference, and the first temperature difference is compared with a first cooling temperature difference threshold. If the first temperature difference is greater than or equal to the first cooling temperature difference threshold, then a cooling signal is output; If the first temperature difference is less than the first cooling temperature difference threshold, then the average ambient temperature over a medium-to-long-term period is further obtained, and the temperature difference between the average ambient temperature over a medium-to-long-term period and the cooling start-up temperature is calculated. This temperature difference is the second temperature difference, and the second temperature difference is compared with the second cooling temperature difference threshold. If the second temperature difference is greater than or equal to the second cooling temperature difference threshold, a cooling signal is output. If the second temperature difference is less than the second cooling temperature difference threshold, then the long-term average ambient temperature is further obtained, and the temperature difference between the long-term average ambient temperature and the cooling start-up temperature is calculated. This temperature difference is the third temperature difference, and the third temperature difference is compared with the third cooling temperature difference threshold. If the third temperature difference is greater than or equal to the third cooling temperature difference threshold, then a cooling signal is output; If the third temperature difference is less than the third cooling temperature difference threshold, then a standby signal is output.

6. The heat pump unit according to claim 5, characterized in that, When the short-term average ambient temperature is less than or equal to the heating start-up temperature, the controller controls the heat pump unit to switch to heating mode or standby mode using the following method: Based on the current ambient temperature, the temperature difference between the heating start-up temperature and the current ambient temperature is calculated. This temperature difference is the fourth temperature difference, and it is compared with the first heating temperature difference threshold. If the fourth temperature difference is greater than or equal to the first heating temperature difference threshold, then output a heating signal; If the fourth temperature difference is less than the first heating temperature difference threshold, then the average ambient temperature over a medium-to-long-term period is further obtained, and the temperature difference between the heating start-up temperature and the average ambient temperature over a medium-to-long-term period is calculated. This temperature difference is the fifth temperature difference, and the fifth temperature difference is compared with the second heating temperature difference threshold. If the fifth temperature difference is greater than or equal to the second heating temperature difference threshold, then a heating signal is output; If the fifth temperature difference is less than the second heating temperature difference threshold, then the long-term average ambient temperature is further obtained, and the temperature difference between the heating start-up temperature and the long-term average ambient temperature is calculated. This temperature difference is the sixth temperature difference, and the sixth temperature difference is compared with the third heating temperature difference threshold. If the sixth temperature difference is greater than or equal to the third heating temperature difference threshold, then output a heating signal; If the sixth temperature difference is less than the third heating temperature difference threshold, then a standby signal is output.

7. The heat pump unit according to claim 6, characterized in that, The third cooling temperature difference threshold range is 1~2℃, and the third heating temperature difference threshold range is 1~2℃.

8. The heat pump unit according to any one of claims 5-7, characterized in that, The temperature collection and calculation period for the long-term average ambient temperature is 22-24 hours.

Images