阅读说明：本技术 空调系统 (Air conditioning system ) 是由 都学敏 孟建军 张恒 李廷宇 赵玉垒 于 2021-06-29 设计创作，主要内容包括：本发明公开了一种空调系统包括：第二换热器和第一换热器；第一温湿度传感器,设于新风入口处；第二温湿度传感器,其设于第二换热器与风机之间；第三温湿度传感器,其设于新风出口处；旁通支路,利用电子膨胀阀并联在所述第一换热器的两端；控制模块,其用于选择控制方法A或控制方法B；还用于采集各个温湿度传感器的温度和湿度；还用于采集室内设定点N的温度T-N和湿度H-N,采集的数据控制压缩机的频率和电子膨胀阀的开启；所述第一换热器的换热量小于所述第二换热器的换热量。实现一套制冷循环系统将新风处理到室内设定的温度值和湿度值附近,且有效的利用了冷凝器的热量,最大限度的提高了机组能效。(The invention discloses an air conditioning system comprising: a second heat exchanger and a first heat exchanger; the first temperature and humidity sensor is arranged at the fresh air inlet; the second temperature and humidity sensor is arranged between the second heat exchanger and the fan; the third temperature and humidity sensor is arranged at the fresh air outlet; the bypass branch is connected in parallel to two ends of the first heat exchanger by using an electronic expansion valve; a control module for selecting control method A or control method B; the temperature and humidity sensor is also used for acquiring the temperature and the humidity of each temperature and humidity sensor; and also for acquiring indoor set pointsTemperature T of N N And humidity H N The collected data controls the frequency of the compressor and the opening of the electronic expansion valve; the heat exchange quantity of the first heat exchanger is smaller than that of the second heat exchanger. The fresh air is processed to the temperature value and the humidity value which are set indoors by one set of refrigeration cycle system, the heat of the condenser is effectively utilized, and the energy efficiency of the unit is improved to the maximum extent.)

1. Air conditioning system, its characterized in that, along the new trend by outdoor entering indoor direction, include:

a second heat exchanger and a first heat exchanger;

the first temperature and humidity sensor is arranged at the fresh air inlet;

the second temperature and humidity sensor is arranged between the second heat exchanger and the fan;

the third temperature and humidity sensor is arranged at the fresh air outlet;

the bypass branch is connected in parallel to two ends of the first heat exchanger by using an electronic expansion valve;

a control module for selecting control method A or control method B; and is also used for collecting the temperature T of the first temperature and humidity sensor₁And humidity H₁The temperature T of the second temperature and humidity sensor₂And humidity H₂The temperature T of the third temperature and humidity sensor₃And humidity H₃；

The control method A comprises the steps of taking the condensation temperature Tc or the evaporation temperature Te as a control target;

wherein the control module is further configured to acquire a temperature T of an indoor set point N_NAnd humidity H_NAnd is also used for collecting the temperature T of the outdoor air point W_WAnd humidity H_W(ii) a The controller is also used for controlling the frequency of the compressor and the opening of the electronic expansion valve according to the acquired data;

the heat exchange quantity of the first heat exchanger is smaller than that of the second heat exchanger.

2. The air conditioning system of claim 1, wherein the control module is further configured to meterCalculating an enthalpy value h of the indoor setpoint N_NMoisture content d_NAnd dew point temperature T_Nl(ii) a Is also used for calculating the enthalpy value h of the outdoor air W point_WMoisture content d_WAnd dew point temperature T_Wl。

3. Air conditioning system according to claim 1, characterized in that in control method a, with the condensation temperature Tc as the control target, the control module is adapted to calculate the temperature T of the introduction point L_LAnd according to the temperature T_LTemperature T of the second temperature and humidity sensor₂So that the condensing temperature Tc satisfies Tc>T_L+ K, K are correction values.

4. Air conditioning system according to claim 1, characterized in that in control method a, with evaporation temperature Te as control target, the control module is adapted to control temperature T according to indoor set point N_NTemperature T of the third temperature and humidity sensor₃And adjusting the frequency of the compressor and controlling the opening of the electronic expansion valve according to the comparison result.

5. The air conditioning system as claimed in claim 1, wherein one side of the second heat exchanger is provided with an air valve for bypassing fresh air.

6. Air conditioning system according to claim 5, characterized in that in control method B, the control module is adapted to calculate the total air volume G and also to calculate the enthalpy h of the point of introduction O_OAnd calculating the air volume G at the second temperature and humidity sensor according to the air volume balance and the heat balance₂And the air volume G of the outdoor air point W_WTo determine the action of the damper.

7. Air conditioning system according to claim 1, characterized in that in control method B the control module is also adapted to determine the temperature T according to the indoor setpoint N_NTemperature T of the third temperature and humidity sensor₃Is compared withIf the frequency of the compressor is adjusted.

8. The air conditioning system of claim 5, wherein in control method B, the control module is further configured to re-determine the temperature T of the second temperature/humidity sensor₂And humidity H₂Determining the temperature T of the point of introduction Y_YAnd humidity H_Y(ii) a And is also used for recalculating the air volume G at the second temperature and humidity sensor₂And the air volume G of the outdoor air point W_WTo adjust the temperature T of the air valve to the third temperature and humidity sensor₃Satisfy T₃≤|T_N±1|℃。

9. Air conditioning system according to claim 3, characterized in that the correction value K is in the range 1-5 ℃.

10. The air conditioning system of claim 1, wherein the control module is configured to control the indoor air enthalpy based on a value h_NEnthalpy value h of outdoor air_WThe control method A or the control method B is selected for the size judgment of (1).

Technical Field

The invention relates to the technical field of air conditioners, in particular to an air conditioning system.

Background

The return south usually occurs in alternate seasons of 2 months and 3 months, usually at the end of 4 months, the outdoor temperature is between 0 and 15 ℃, the relative humidity is more than 80 percent, if the traditional cooling dehumidification method is adopted, the temperature of the treated fresh air is very low, even lower than 10 ℃, and strong cold wind feeling exists; on the other hand, because the air temperature is low, a low evaporation temperature is required to condense the moisture in the air, and in order to solve this problem, reheating methods such as electric heating and heating coils are generally used, which results in energy waste due to cold and heat compensation. In addition, when outdoor temperature is high in summer, most of the existing fresh air processors use the air supply temperature as a control target, and cannot process fresh air to an indoor state point, so that the indoor unit can bear not only all indoor loads but also partial fresh air loads, and two solutions are generally available: the capacity of the indoor unit is increased, so that the construction cost is increased; the indoor unit only processes indoor load, which may cause the temperature in the room to be unable to reach the set value after the fresh air is introduced, or when the outdoor humidity is high, the fresh air processor does not process completely, thereby increasing the indoor humidity.

In summary, an air conditioning system is needed to solve the problem of the prior art that the heat exchange efficiency is reduced or the temperature of the fresh air supply is low under the high-humidity working condition.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides an air conditioning system, which realizes that a set of refrigeration cycle system processes fresh air to be close to indoor set temperature and humidity values, effectively utilizes the heat of a condenser and improves the energy efficiency of a unit to the maximum extent.

In order to achieve the purpose, the invention adopts the following technical scheme:

an air-conditioning system is provided with an air-conditioning system,

along the indoor direction of new trend by outdoor entering, include:

a second heat exchanger and a first heat exchanger;

the first temperature and humidity sensor is arranged at the fresh air inlet;

the second temperature and humidity sensor is arranged between the second heat exchanger and the fan;

the third temperature and humidity sensor is arranged at the fresh air outlet; the bypass branch is connected in parallel to two ends of the first heat exchanger by using an electronic expansion valve;

a control module for selecting control method A or control method B; and is also used for collecting the temperature T of the first temperature and humidity sensor₁And humidity H₁The temperature T of the second temperature and humidity sensor₂And humidity H₂The temperature T of the third temperature and humidity sensor₃And humidity H₃；

The control method A comprises the steps of taking the condensation temperature Tc or the evaporation temperature Te as a control target;

wherein the control module is further configured to acquire a temperature T of an indoor set point N_NAnd humidity H_NAnd is also used for collecting the temperature T of the outdoor air point W_WAnd humidity H_W(ii) a The controller is also used for controlling the frequency of the compressor and the opening of the electronic expansion valve according to the acquired data;

the heat exchange quantity of the first heat exchanger is smaller than that of the second heat exchanger.

In some embodiments of the invention, the control module is also configured to calculate an enthalpy value h of the indoor setpoint N_NMoisture content d_NAnd dew point temperature T_Nl(ii) a Is also used for calculating the enthalpy value h of the outdoor air W point_WMoisture content d_WAnd dew point temperature T_Wl。

In some embodiments of the invention, in the control method a, the control module is configured to calculate the temperature T of the introduction point L, while taking the condensation temperature Tc as a control target_LAnd according to the temperature T_LTemperature T of the second temperature and humidity sensor₂Regulating the frequency of said compressorSo that the condensing temperature Tc satisfies Tc>T_L+ K, K are correction values.

In some embodiments of the invention, in control method a, said control module is adapted to control the temperature T according to the indoor setpoint N, while targeting the evaporation temperature Te as control target_NTemperature T of the third temperature and humidity sensor₃And adjusting the frequency of the compressor and controlling the opening of the electronic expansion valve according to the comparison result.

In some embodiments of the invention, the outdoor unit module is provided with a damper for releasing part of the fresh air.

In some embodiments of the invention, in the control method B, the control module is configured to calculate the total air volume G and also to calculate the enthalpy h of the introduction point O_OAnd calculating the air volume G at the second temperature and humidity sensor according to the air volume balance and the heat balance₂And the air volume G of the outdoor air point W_WTo determine the action of the damper.

In some embodiments of the invention, in the control method B, the control module is also configured to control the indoor set point N based on the temperature T of the indoor set point N_NTemperature T of the third temperature and humidity sensor₃The comparison adjusts the frequency of the compressor.

In some embodiments of the invention, in the control method B, the control module is further configured to re-determine the temperature T of the second temperature and humidity sensor₂And humidity H₂Determining the temperature T of the point of introduction Y_YAnd humidity H_Y(ii) a And is also used for recalculating the air volume G at the second temperature and humidity sensor₂And the air volume G of the outdoor air point W_WTo adjust the temperature T of the air valve to the third temperature and humidity sensor₃Satisfy T₃≤|T_N±1|℃。

In some embodiments of the invention, the correction value K is in the range of 1-5 ℃.

In some embodiments of the invention, the control module is based on the enthalpy h of the indoor air_NEnthalpy value h of outdoor air_WThe control method A or the control method B is selected for the size judgment of (1).

Compared with the prior art, the technical scheme of the invention has the following technical effects:

according to the invention, through reasonably designing the heat exchange areas of the evaporator and the condenser and increasing the air valve, a set of refrigeration cycle system is realized to process fresh air to the vicinity of indoor set temperature value and humidity value, the heat of the condenser is effectively utilized, and the unit energy efficiency is improved to the maximum extent; on the one hand, the problem that the air state can enter a liquid area due to cooling and dehumidification under the low-temperature high-humidity working condition to cause the large-area dewing and heat exchange efficiency of the heat exchanger to be reduced can be solved, and on the other hand, the problem that the air supply temperature of fresh air after cooling and dehumidification is too low can be solved under the high-temperature high-humidity working condition.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a flowchart of a selection control method of the air conditioning system.

Fig. 2 is a schematic structural diagram of an air conditioning system in the control method a.

Fig. 3 is a psychrometric chart of the air treatment process in the control method a.

Fig. 4 is a control flowchart in which the condensing temperature is set as a control target.

Fig. 5 is a control flowchart in which the evaporation temperature is set as a control target.

Fig. 6 is a schematic structural diagram of an air conditioning system in the control method B.

Fig. 7 is an enthalpy diagram of the air treatment process in the control method B.

Fig. 8 is a control flowchart in the control method B.

Reference numerals: 1-a compressor; 2-a four-way valve; 3-a first heat exchanger; 4-a throttling device; 5-a second heat exchanger; 6-fresh air inlet; 7-a fan motor; 8-a fresh air outlet; 9-a first temperature and humidity sensor; 10-a second temperature and humidity sensor; 11-a third temperature and humidity sensor; 99-a bypass branch; 100-an electronic expansion valve; 101-air valve.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it is to be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the present invention.

In the description of the present invention, it should be noted that the terms "mounted," "connected," and "connected" are to be construed broadly and may be, for example, fixedly connected, detachably connected, or integrally connected unless otherwise explicitly stated or limited. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art. In the foregoing description of embodiments, the particular features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments or examples.

The terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

The air conditioner performs a refrigeration cycle of the air conditioner by using a compressor, a condenser, an expansion valve, and an evaporator in the present application. The refrigeration cycle includes a series of processes involving compression, condensation, expansion, and evaporation, and supplies refrigerant to the air that has been conditioned and heat-exchanged.

The compressor compresses a refrigerant gas in a high-temperature and high-pressure state and discharges the compressed refrigerant gas. The discharged refrigerant gas flows into the condenser. The condenser condenses the compressed refrigerant into a liquid phase, and heat is released to the surrounding environment through the condensation process.

The expansion valve expands the liquid-phase refrigerant in a high-temperature and high-pressure state condensed in the condenser into a low-pressure liquid-phase refrigerant. The evaporator evaporates the refrigerant expanded in the expansion valve and returns the refrigerant gas in a low-temperature and low-pressure state to the compressor. The evaporator can achieve a cooling effect by heat-exchanging with a material to be cooled using latent heat of evaporation of a refrigerant. The air conditioner can adjust the temperature of the indoor space throughout the cycle.

The outdoor unit of the air conditioner refers to a portion of a refrigeration cycle including a compressor and an outdoor heat exchanger, the indoor unit of the air conditioner includes an indoor heat exchanger, and an expansion valve may be provided in the indoor unit or the outdoor unit.

The indoor heat exchanger and the outdoor heat exchanger serve as a condenser or an evaporator. The air conditioner is used as the heater of control method B when the indoor heat exchanger is used as the condenser, and as the cooler of control method a when the indoor heat exchanger is used as the evaporator.

Referring to fig. 2, the air conditioning system includes:

along the indoor direction of new trend by outdoor entering, include:

a second heat exchanger 5 and a first heat exchanger 3;

the first temperature and humidity sensor 9 is arranged at the fresh air inlet 6;

the second temperature and humidity sensor 10 is arranged between the second heat exchanger 5 and the fan 7;

a third temperature and humidity sensor 11 arranged at the fresh air outlet 8; a bypass branch 99 connected in parallel to both ends of the first heat exchanger 3 by an electronic expansion valve 100;

a control module for selecting control method A or control method B; and is also used for collecting the temperature T of the first temperature and humidity sensor 9₁And humidity H₁The temperature T of the second temperature/humidity sensor 10₂And humidity H₂The temperature T of the third temperature and humidity sensor 11₃And humidity H₃；

The control method A comprises the steps of taking the condensation temperature Tc or the evaporation temperature Te as a control target;

wherein the control module is further configured to acquire a temperature T of an indoor set point N_NAnd humidity H_NAnd is also used for collecting the temperature T of the outdoor air point W_WAnd humidity H_WThe controller is also used for controlling the frequency of the compressor 1 and the opening of the electronic expansion valve 101 according to the acquired data;

the heat exchange amount of the first heat exchanger 3 is less than that of the second heat exchanger 5.

In fig. 2, OA indicates outdoor, SA indicates indoor, and the arrow indicates the flow direction of fresh air.

In some embodiments of the invention, the first heat exchanger 3 is used as an evaporator, and the cooling capacity is q1 KW; the second heat exchanger 5 is used as a condenser, and the heat dissipation is q2 KW; the power consumption of the compressor is q3 KW. Therefore, q2= q1+ q3, i.e. the heat exchange capacity of the condenser is greater than that of the evaporator. When the air volume is the same, the heat exchange amount of the second heat exchanger is larger than that of the first heat exchanger, and other conditions are the same, the area of the second heat exchanger 5 is larger than that of the first heat exchanger 3.

In some embodiments of the present invention, referring to fig. 1, after the air conditioning system is turned on, the control module first determines the enthalpy h of the indoor air_NEnthalpy value h of outdoor air_WThe control method A or the control method B is selected for the size judgment of (1).

When the enthalpy value of the indoor air is larger than that of the outdoor air (h)_N＞h_W) At this time, the outdoor air temperature is low but the humidity is high, the control module selects the control method a, the first heat exchanger 3 is an evaporator, and the second heat exchanger 5 is a condenser. In the control methodIn A, the control module can select the condensation temperature Tc or the evaporation temperature Te as a control target. When the enthalpy value of the indoor air is not more than the enthalpy value (h) of the outdoor air_N≤h_W) At this time, the outdoor air has high temperature and high humidity, the control module selects the control method B, the second heat exchanger 5 serves as an evaporator, and the first heat exchanger 3 serves as a condenser.

[ control method A ]

In some embodiments of the present invention, in the control method a, the outdoor air temperature is low, but the outdoor air humidity is high, and if a control strategy of dehumidification before heating is adopted, the state of the air after cooling and dehumidification is likely to enter the liquid region. In order to ensure that the liquid area is not entered during cooling and dehumidification, the liquid area is heated and then cooled and dehumidified.

When the condensation temperature Tc is taken as a control target, the control module is used for calculating the temperature T of the introduction point L_LAnd according to the temperature T_LTemperature T of the second temperature and humidity sensor₂So that the condensing temperature Tc satisfies Tc>T_L+ K, K are correction values.

Reference is made to the psychrometric chart of the air treatment process illustrated in figure 3 and the control flow diagram of figure 4. After the fan 7 is started, the control module first detects the temperature T of the indoor set point N_NAnd humidity H_NAnd the temperature T of the outdoor air point W_WAnd humidity H_WThen calculating the moisture content d of the indoor set point N_NAnd dew point temperature T_NlAnd the dew point temperature T at point N is shown in FIG. 3_NlThe dew point temperature T at which the position is marked as O point, namely the temperature corresponding to the position where the N point is positioned on the same humidity line and the relative humidity is 100 percent is the N point_Nl(ii) a The control module also has a moisture content d for the outdoor air W point_WCalculating, and finally calculating the heat-humidity ratio epsilon corresponding to the connecting line of the O point and the W point; the control module is used for controlling the temperature of the water according to the heat-humidity ratio epsilon and the moisture content d_NAnd a moisture content d_WDetermining the location of the introduction point L, as shown in FIG. 3, with the moisture content d_WThe intersection point of the heat-humidity ratio epsilon passing through the point N, namely the introduction point L and the point W are positioned on the same humidity line and are positioned on a parallel line of the same heat-humidity ratio epsilon with the point N.

After the compressor 1 is started, the control module is programmed to introduce the temperature T of the point L_LFor the control target, that is, so that the condensing temperature Tc satisfies Tc>T_L+ K, K being the correction value, the value range of K being 1-5 ℃.

The control module passes the temperature T of the second temperature and humidity sensor 10₂And determining the temperature T₂Whether or not T is satisfied₂>| T_L±1|℃。

When T is₂>| T_LThe compressor changes the frequency at + -1 deg.C.

The control module continuously judges the current temperature T₂Whether or not T is satisfied₂≤| T_LAnd +/-1 ℃ when the current frequency is met, the compressor maintains the current frequency to operate.

In some embodiments of the present invention, referring to FIG. 5, the evaporating temperature Te is taken as the control target, i.e. the dew point temperature T of N point is directly taken as_NlFor the control purpose, the evaporating temperature Te is enabled to satisfy Te is less than or equal to T_NlK is a correction value, and the value range of K is 1-5 ℃.

The control module collects the temperature T of the third temperature and humidity sensor 11₃And determining the temperature T₃Whether or not T is satisfied₃>| T_N±1|℃。

When T is₃>| T_NThe compressor changes the frequency at + -1 deg.C.

The control module continuously judges the current temperature T₃Whether or not T is satisfied₃≤| T_N+/-1 ℃ of temperature, if so, maintaining the current frequency operation of the compressor;

if not, continuing to detect; determine the temperature T of the third temperature/humidity sensor 11₃Whether or not T is satisfied₃＜T_NAnd (3) keeping the temperature at 1 ℃ below zero for 30 minutes, if so, further judging whether the compressor operates at the lowest frequency, and if so, indicating that the refrigerating capacity of the evaporator is excessive, so that the control module opens the electronic expansion valve 100 to bypass a part of refrigerant. And then continuously judging whether the opening degree of the electronic expansion valve 100 meets the requirement that the opening degree of the electronic expansion valve 100 is less than or equal to TN +/-1 ℃ if the opening degree of the electronic expansion valve meets the requirement that the opening degree of the electronic expansion valve is less than or equal to T3.

In some embodiments of the present invention, in the control method a, the circulation process of the refrigerant is as follows: the refrigerant is compressed in the compressor 1 to become a high-temperature and high-pressure gaseous refrigerant; then flows to a second heat exchanger 5 serving as a condenser through a four-way valve 2, releases heat to fresh air outside the pipe in the second heat exchanger 5, and then becomes a low-temperature high-pressure gaseous refrigerant; then the refrigerant flows to a throttling device 4, and the refrigerant is throttled and decompressed in the throttling device 4 to become a low-temperature and low-pressure liquid refrigerant; then, the refrigerant continues to flow to the first heat exchanger 3 serving as an evaporator, and exchanges heat with fresh air outside the pipe in the first heat exchanger 3 to absorb the heat of the fresh air and then becomes a low-temperature and low-pressure gaseous refrigerant; finally, the refrigerant returns to the compressor 1 through the four-way valve 2 again to complete one cycle.

When the electronic expansion valve 100 is opened, a small portion of the refrigerant is returned directly to the compressor direction through the bypass branch 99 without passing through the evaporator 3.

In some embodiments of the invention, the process of fresh air processing: outdoor air (fresh air) enters the device from a fresh air inlet 6, is heated by a second heat exchanger 5 serving as a condenser, the temperature is raised, the moisture content is unchanged, the outdoor air is conveyed by a fan 7 to an inlet of a first heat exchanger 3 serving as an evaporator, and is cooled by the first heat exchanger 3, water vapor carried in the fresh air is condensed when meeting the condensation, so that the temperature and the moisture content of the fresh air are both reduced after passing through the first heat exchanger 3, and a fresh air treatment process is completed.

[ control method B ]

In some embodiments of the present invention, in the control method B, the outdoor air temperature is high and the humidity is large. At the moment, the second heat exchanger 5 is used as an evaporator, the first heat exchanger 3 is used as a condenser, and because the area of the first heat exchanger 3 is smaller than that of the second heat exchanger 5, if the fresh air is completely processed to the positions with moisture contents such as N points and the like set in the room, the processing capacity of the evaporator is larger than that of the condenser, but the realization is impossible according to a refrigerating system. Therefore, in order to reduce the processing capacity of the evaporator and achieve the energy saving effect, referring to fig. 6, a part of fresh air is bypassed by adding a fresh air bypass damper 101 without being processed by the second heat exchanger 5, and only a part of fresh air passes through the second heat exchanger 5.

In the present inventionIn some illustrative embodiments, reference is made to the psychrometric chart of the air treatment process illustrated in figure 7, and the control flow diagram of figure 8. After the fan 7 is started, the control module first detects the temperature T of the indoor set point N_NAnd humidity H_NTemperature T of outdoor air point W_WAnd humidity H_WAnd the rotational speed of the fan; then the enthalpy h of the indoor set point N is calculated_NMoisture content d_NAnd dew point temperature T_NlAnd further calculating the enthalpy value h of the W point of the outdoor air_NMoisture content d_W(ii) a And the control module determines the total air volume G according to the rotating speed of the fan.

The compressor 1 is started, the second heat exchanger 5 is used as an evaporator, the first heat exchanger 3 is used as a condenser, and the evaporation temperature Te is controlled to be less than T_Nl-2℃（T_NlDew point temperature, which is the indoor set point N, the calculation of which is documented above); then according to the temperature T detected by the second temperature and humidity sensor 10₂And humidity H₂Confirming the position of the Y point; then, according to the intersection point of the connecting line of the Y point and the W point and the moisture content line of the N point, the Z point is obtained (as shown in figure 7); according to the air volume balance formula G = G_Y+G_WFormula G for heat balance_Wh_W+G_Yh_Y=Gh_ZTo find G_YAnd G_WAnd then controls the air valve 101 to act.

The control module collects the temperature T of the third temperature and humidity sensor 11₃And determining the temperature T₃Whether or not T is satisfied₃>| T_N±1|℃。

When T is₃>| T_NThe compressor changes the frequency at + -1 deg.C.

Recalculating the Y-point position after the frequency adjustment of the compressor 1, and recalculating G according to the above logic_YAnd G_WThe position of the damper 101 is readjusted.

The control module continuously judges the current temperature T₃Whether or not T is satisfied₃≤| T_NAnd +/-1 ℃ of temperature, if so, maintaining the current frequency operation of the compressor.

In some embodiments of the present invention, in the control method B, the refrigerant cycle process is as follows: the refrigerant is compressed in the compressor 1 to become a high-temperature and high-pressure gaseous refrigerant; then flows to a first heat exchanger 3 serving as a condenser through a four-way valve 2, releases heat to fresh air outside the pipe in the first heat exchanger 3, and then becomes a low-temperature high-pressure gaseous refrigerant; then the refrigerant flows to a throttling device 4, and is throttled and decompressed in the throttling device 4 to become a low-temperature and low-pressure liquid refrigerant; then, the refrigerant continues to flow to a second heat exchanger 5 serving as an evaporator, and exchanges heat with fresh air outside the second heat exchanger 5 to absorb the heat of the fresh air and then becomes a low-temperature and low-pressure gaseous refrigerant; finally, the refrigerant returns to the compressor 1 through the four-way valve 2 again to complete one cycle.

In some embodiments of the invention, the process of fresh air processing: outdoor air (new trend) gets into the device by new trend entry 6, and earlier through the cooling of the second heat exchanger 5 as the evaporimeter, vapor that carries in the new trend this moment meets the condensation and knots out, therefore the new trend temperature reduces, and the moisture content reduces, reachs the entry as the first heat exchanger 3 of condenser through the transportation of fan 7, through the heating of condenser, and the new trend temperature risees, accomplishes a new trend processing procedure.

In some embodiments of the invention, the form of the fan 7 may be various, such as centrifugal, turbine, crossflow, etc.; the electronic expansion valve 100 may also be other forms of throttling devices; the damper 101 may be of various types, such as a flat plate rotary type, a movable type, a louver type, etc.

According to the invention, through reasonably designing the heat exchange areas of the evaporator and the condenser and increasing the air valve, a set of refrigeration cycle system is realized to process fresh air to the vicinity of indoor set temperature value and humidity value, the heat of the condenser is effectively utilized, and the unit energy efficiency is improved to the maximum extent; on the one hand, the problem that the air state can enter a liquid area due to cooling and dehumidification under the low-temperature high-humidity working condition to cause the large-area dewing and heat exchange efficiency of the heat exchanger to be reduced can be solved, and on the other hand, the problem that the air supply temperature of fresh air after cooling and dehumidification is too low can be solved under the high-temperature high-humidity working condition.

In the foregoing description of embodiments, the particular features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments or examples.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.