Air conditioning unit and control method thereof

Abstract

The invention discloses an air conditioning unit and a control method thereof, the air conditioning unit comprises an air supply channel and an air return channel communicated with the interior of a room, and a first-stage evaporator, a rotary dehumidifier adsorption area and a second-stage evaporator which are sequentially distributed in the air supply direction are installed in the air supply channel; the air supply channel is provided with a primary mixed air return port and a secondary mixed air return port which are communicated with the air return channel, the primary mixed air return port is located between the air outlet side of the first-stage evaporator and the air inlet side of the adsorption area of the rotary dehumidifier, and the secondary mixed air return port is located between the air outlet side of the adsorption area of the rotary dehumidifier and the air inlet side of the second-stage evaporator. The indoor return air is introduced into the air inlet side and the air outlet side of the adsorption area of the rotary dehumidifier, the low-temperature and low-humidity indoor return air is used for supplementing the fresh air volume, the burden of an air conditioning unit is reduced, and the effect of accurately adjusting the air supply temperature can be achieved by adjusting the return air volume of primary return air and secondary return air.

Description

Technical Field

[0001] The present invention relates to the technical field of air conditioning units, and in particular to an air conditioning unit with high-efficiency cold and heat recovery and a control method thereof. Background Art

[0002] In archives and other places where text and video materials need to be preserved for a long time, it is very important to keep the temperature and humidity of the indoor environment constant to ensure the integrity and readability of the materials. These places usually require the indoor environment to be in a low temperature and low humidity state to prevent paper materials from getting damp and moldy, and to prevent adverse changes in the physical and chemical properties of the video materials.

[0003] However, the current air conditioning system used to maintain a constant low temperature and low humidity in the archives' indoor environment has the characteristics of low fresh air ratio, low indoor return air temperature and high rotor regeneration air temperature. Directly discharging low-temperature indoor return air to the outside will cause a waste of cooling capacity, and the indoor environment completely relies on the air conditioning unit to cool and dehumidify the outdoor fresh air, which increases the burden of the air conditioning unit. In addition, directly discharging high-temperature regeneration air to the outside will cause heat waste, and the low-temperature airflow after dehumidification and cooling relies on electric heating devices to adjust the supply air temperature, resulting in unnecessary energy consumption.

[0004] Therefore, how to design an air-conditioning unit with efficient heat and cold recovery and its control method is a technical problem that needs to be solved urgently in the industry. Summary of the invention

[0005] In order to solve the problem of energy waste in existing air-conditioning units, the present invention proposes an air-conditioning unit and a control method thereof, which can recycle the cold energy of indoor return air and use the regenerated air as a heat source for supply air reheating, thereby achieving precise control of the supply air temperature and meeting the high-efficiency and energy-saving operation of the unit.

[0006] The technical solution adopted by the present invention is to design an air-conditioning unit, including: an air supply duct and a return air duct connected to the indoor room, wherein a primary evaporator, a rotary dehumidifier adsorption zone, and a secondary evaporator are installed in the air supply duct in sequence along the air supply direction; the air supply duct is provided with a primary mixed return air inlet and a secondary mixed return air inlet connected to the return air duct, the primary mixed return air inlet is located between the air outlet side of the primary evaporator and the air inlet side of the rotary dehumidifier adsorption zone, and the secondary mixed return air inlet is located between the air outlet side of the primary evaporator and the air inlet side of the rotary dehumidifier adsorption zone, and the secondary mixed return air inlet is located between the air outlet side of the rotary dehumidifier adsorption zone and the air inlet side of the secondary evaporator.

[0007] Furthermore, the air supply channel is also provided with a pre-cooling section located on the air inlet side of the primary heat exchanger, and the pre-cooling section is connected to the return air channel through a pre-cooling return air port.

[0008] Furthermore, the precooling section is equipped with a precooling heat exchanger, which is provided with a return air heat exchange pipeline for circulating indoor return air. The indoor return air sent out from the precooling return air outlet is discharged outdoors through the return air heat exchange pipeline.

[0009] Furthermore, the air conditioning unit also includes: a regeneration channel, in which a regeneration air heating device and a rotary dehumidifier regeneration zone are installed, which are sequentially distributed along the regeneration air direction. The air supply channel is also provided with a reheating section located on the air outlet side of the secondary evaporator, and the reheating section is connected to the air outlet end of the regeneration channel through a regeneration air outlet.

[0010] Furthermore, the reheat section is equipped with a reheat heat exchanger, and the reheat heat exchanger is provided with a regeneration air heat exchange pipeline for circulating the regeneration air, and the regeneration air sent out from the regeneration air outlet is discharged outdoors through the regeneration air heat exchange pipeline.

[0011] Furthermore, a humidifier is installed in the air supply channel, and the humidifier is located on the air outlet side of the reheat heat exchanger.

[0012] The present invention also proposes a control method for an air conditioning unit, which is applied to the above-mentioned air conditioning unit, and the control method comprises:

[0013] Detect the actual air supply temperature of the air supply channel;

[0014] Compare the actual supply air temperature with the target temperature range;

[0015] When the actual supply air temperature is higher than the target temperature range, the air valve opening of the primary mixed return air outlet is reduced, and the air valve opening of the secondary mixed return air outlet is increased;

[0016] When the actual supply air temperature is lower than the target temperature range, the air valve opening of the primary mixed return air outlet is increased, and the air valve opening of the secondary mixed return air outlet is reduced;

[0017] When the actual supply air temperature is within the target temperature range, the air valve opening of the primary mixed return air outlet and the air valve opening of the secondary mixed return air outlet remain unchanged.

[0018] Furthermore, the control method also includes:

[0019] Detecting the actual supply air temperature of the supply air duct and the actual return air temperature of the return air duct;

[0020] Analyze the changing status of actual supply air temperature and actual return air temperature;

[0021] When the actual supply air temperature fluctuates, the opening of the air valve of the pre-cooling return air outlet is adjusted according to the actual supply air temperature;

[0022] When the actual return air temperature fluctuates and the actual supply air temperature is stable, the opening of the air valve of the pre-cooling return air outlet is adjusted according to the actual return air temperature;

[0023] When the actual supply air temperature and the actual return air temperature are both stable, the opening of the air valve of the pre-cooling return air outlet remains unchanged.

[0024] Further, the change status of the actual supply air temperature and the actual return air temperature is analyzed including:

[0025] Determine whether the actual supply air temperature is within the target temperature range. If so, the actual supply air temperature is stable; if not, the actual supply air temperature fluctuates.

[0026] Determine whether the actual return air temperature is within the target temperature range. If so, the actual return air temperature is stable; if not, the actual return air temperature fluctuates.

[0027] Furthermore, adjusting the air valve opening of the pre-cooling return air outlet according to the actual supply air temperature includes:

[0028] Compare the actual supply air temperature with the target temperature range;

[0029] When the actual supply air temperature is higher than the target temperature range, increase the opening of the air valve at the pre-cooling return air outlet;

[0030] When the actual supply air temperature is lower than the target temperature range, reduce the opening of the air valve at the pre-cooling return air outlet.

[0031] Further, adjusting the opening of the air valve of the pre-cooling return air outlet according to the actual return air temperature includes:

[0032] Compare the actual return air temperature with the target temperature range;

[0033] When the actual return air temperature is higher than the target temperature range, reduce the opening of the air valve at the pre-cooling return air outlet;

[0034] When the actual return air temperature is lower than the target temperature range, increase the opening of the air valve at the pre-cooling return air outlet.

[0035] Furthermore, the control method also includes:

[0036] Detect the actual air supply temperature of the air supply channel;

[0037] Compare the actual supply air temperature with the target temperature range;

[0038] When the actual supply air temperature is higher than the target temperature range, the regeneration air volume of the regeneration air outlet is reduced;

[0039] When the actual air supply temperature is lower than the target temperature range, increase the regeneration air volume at the regeneration air outlet;

[0040] When the actual supply air temperature is within the target temperature range, the regeneration air volume of the regeneration air outlet remains unchanged.

[0041] Compared with the prior art, the present invention has at least one of the following beneficial effects:

[0042] 1. Design primary mixed return air vents and secondary mixed return air vents to introduce indoor return air into the air inlet and air outlet sides of the rotary dehumidifier adsorption zone, and use low-temperature and low-humidity indoor return air to supplement the fresh air volume to reduce the burden on the air conditioning unit. The return air volume of the primary return air and the secondary return air can also be adjusted to achieve the effect of accurately adjusting the supply air temperature;

[0043] 2. Design pre-cooling return air vents and regeneration air vents to use low-temperature indoor return air to pre-cool high-temperature outdoor fresh air, effectively improve the cooling recovery efficiency of indoor return air, and use high-temperature regeneration air as a heat source for supply air reheating to assist in adjusting the supply air temperature and reduce the operating energy consumption of the air conditioning unit;

[0044] 3. Through the linkage adjustment of return air volume and regeneration air volume, the supply air temperature can be adjusted quickly and accurately, and the air-conditioning unit can operate efficiently and energy-savingly. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The present invention is described in detail below with reference to the embodiments and accompanying drawings, wherein:

[0046] Figure 1 is a connection diagram of an embodiment of the present invention;

[0047] Figure 2 is a connection diagram of another embodiment of the present invention;

[0048] Figure 3 is a connection diagram of a preferred embodiment of the present invention;

[0049] Figure 4 It is a schematic diagram of the return air processing flow of the control method of the present invention;

[0050] Figure 5 Schematic diagram of the fresh air treatment process of the control method of the present invention;

[0051] Figure 6 It is a schematic diagram of the regeneration air processing flow of the control method of the present invention; Description of the drawings:

[0053] 1. Air filter; 2. Precooling heat exchanger; 3. Primary evaporator; 4. Rotary dehumidifier; 5. Chemical filter; 6. Secondary evaporator; 7. Reheat heat exchanger; 8. Humidifier; 9. Blower; 10. Proportional valve; 11. Regeneration air heating device; 12. Regeneration fan;

[0054] X1, fresh air; X2, fresh air; P1, return air exhaust; P2, regeneration air exhaust; P3, reheat exhaust; S, supply air flow; H, indoor return air; H1, pre-cooling return air inlet; H2, primary mixing return air inlet; H3, secondary mixing return air inlet; Z, regeneration air inlet. DETAILED DESCRIPTION

[0055] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0056] like Figure 1 As shown, the air conditioning unit proposed in the present invention can realize efficient cold and heat recovery, and the air conditioning unit includes: an air supply channel, a return air channel and a rotary dehumidifier 4. The air supply channel is equipped with a blower 9, and the blower 9 drives the air flow in the air supply channel from the air inlet to the air outlet. The air outlet of the air supply channel is connected to the room, and the air supply channel is equipped with a primary evaporator 3, a rotary dehumidifier adsorption area and a secondary evaporator 6 distributed in sequence along the air supply direction. When the air conditioning unit is working, the blower 9 is turned on, and the fresh air X1 enters the air supply channel. The air flow first passes through the primary evaporator 3 for cooling, then passes through the rotary dehumidifier adsorption area for dehumidification, and then passes through the secondary evaporator 6 for cooling again. The air supply air flow S after multiple treatments enters the room from the air outlet to keep the indoor environment at a low temperature and low humidity.

[0057] Generally speaking, the temperature of indoor return air H is between 6 and 12°C, and directly discharging it to the outdoors will cause a waste of cooling capacity. In order to achieve the recycling of indoor return air H, the air supply duct of the present invention is provided with a primary mixed return air port H2 and a secondary mixed return air port H3 connected to the return air duct. The primary mixed return air port H2 is located between the air outlet side of the primary evaporator 3 and the air inlet side of the adsorption zone of the rotary dehumidifier, and the secondary mixed return air port H3 is located between the air outlet side of the adsorption zone of the rotary dehumidifier and the air inlet side of the secondary evaporator 6. The air inlet of the return air duct is connected to the indoor room, and the indoor return air H entering the return air duct can flow from the primary mixed return air port H2 and the secondary mixed return air port H3 to the air supply duct.

[0058] This design introduces the indoor return air H into the air inlet and outlet sides of the adsorption zone of the rotary dehumidifier, and uses the low-temperature and low-humidity indoor return air H to supplement the fresh air volume, reducing the burden on the air conditioning unit. On this basis, the return air volume of the primary return air and the secondary return air is adjusted according to the supply air temperature, which can change the temperature of the mixed air flow on the air inlet side of the secondary evaporator, thereby achieving the effect of flexibly adjusting the supply air temperature.

[0059] The design principle is that the set air outlet temperature of the first-level evaporator 3 is usually close to or equal to the target supply air temperature, that is, the actual air outlet temperature of the first-level evaporator 3 is close to the actual return air temperature of the return air duct. Introducing the indoor return air H into the air outlet side of the first-level evaporator 3 can effectively supplement the fresh air volume and reduce the refrigeration load of the first-level evaporator 3. However, during the rotary dehumidification process, the rotary dehumidifier 4 adsorbs moisture in the air through the adsorbent, and the adsorption process is an exothermic reaction. This exothermic process will cause the air flow temperature on the outlet side to be higher than the air flow temperature on the inlet side. If too much indoor return air H is sent to the inlet side of the adsorption zone of the rotary dehumidifier, the mixed gas temperature on the inlet side of the secondary evaporator will increase, increasing the refrigeration load of the secondary evaporator 6. If too much indoor return air H is sent to the outlet side of the adsorption zone of the rotary dehumidifier, the mixed gas temperature on the inlet side of the secondary evaporator will decrease, causing the air flow temperature on the outlet side of the secondary evaporator to be much lower than the target supply air temperature, increasing the heating load of the subsequent supply air reheating. Therefore, a reasonable allocation of the return air volume on the front and rear sides of the adsorption zone of the rotary dehumidifier can flexibly adjust the supply air temperature.

[0060] like Figure 2 As shown, in some feasible embodiments of the present invention, the air supply duct is further provided with a pre-cooling section, which is located on the air inlet side of the primary evaporator 3. The pre-cooling section is connected to the return air duct through the pre-cooling return air port H1. The low-temperature indoor return air H pre-cools the high-temperature outdoor fresh air X1 entering the air supply duct in the pre-cooling section, thereby effectively improving the cooling recovery efficiency of the indoor return air and reducing the refrigeration load of the primary evaporator 3.

[0061] Since the air supply channel is designed with a primary mixed return air outlet H2 and a secondary mixed return air outlet H3, a certain amount of indoor return air H has been mixed with the fresh air X1 and sent back to the room. If the precooling section also adopts a mixed design, the return air accounts for too much of the supply air flow, affecting the indoor comfort. Therefore, in the preferred solution, the precooling section is equipped with a precooling heat exchanger 2, and the precooling heat exchanger 2 is provided with a return air heat exchange pipeline and a fresh air heat exchange pipeline. The fresh air X1 entering the air supply channel passes through the fresh air heat exchange pipeline, and the indoor return air H introduced by the precooling return air outlet H1 is discharged to the outside through the return air heat exchange pipeline. The fresh air X1 and the indoor return air H exchange heat in the precooling heat exchanger 2, and the fresh air X1 absorbs the cold and cools down, and then flows to the primary evaporator 3. The purpose of designing the precooling heat exchanger 2 is to recycle the coldness of the indoor return air H, and to ensure the proportion of fresh air in the supply air flow S, so that the indoor air is fresh and the user experience is optimized.

[0062] For ease of understanding, a specific application example of the present invention is used for illustration. According to the temperature and humidity requirements of places such as archives, the air-conditioning unit operates in a cooling condition almost all year round. Assuming that the air supply target of the air-conditioning unit is 8°C / 95%, the air outlet target of the primary evaporator 3 is also 8°C / 95%. In summer, the fresh air X1 at 35°C and the indoor return air H at 8°C pass through the precooling heat exchanger 2 in a 1:1 ratio. The temperature of the fresh air flowing out of the precooling heat exchanger 2 is reduced to 23.17°C, and the cooling load of the primary evaporator 3 is reduced by 43.8%. It can be seen that the design of the precooling heat exchanger 2 can greatly reduce the cooling load and achieve energy-saving operation of the unit.

[0063] like Figure 3 As shown, in some feasible embodiments of the present invention, the air conditioning unit further includes: a regeneration channel, the regeneration channel is equipped with a regeneration fan 12, the regeneration fan 12 drives the air flow in the regeneration channel from the air inlet to the air outlet, the air outlet of the regeneration channel is connected to the outside, and the regeneration channel is equipped with a regeneration wind heating device 11 and a rotary dehumidifier regeneration zone distributed in sequence along the regeneration wind direction. When the air conditioning unit is working, the regeneration fan 12 is turned on, and the fresh air X2 is first heated by the regeneration wind heating device 11, then passes through the rotary dehumidifier regeneration zone, and then is discharged to the outside from the air outlet of the regeneration channel.

[0064] Generally speaking, the exhaust temperature of the regeneration air is between 60℃ and 120℃. Directly discharging it to the outside will cause heat waste. In order to realize the recycling of the regeneration air, the air supply channel of the present invention is also provided with a reheating section. The reheating section is located on the air outlet side of the secondary evaporator 6. The reheating section is connected to the air outlet end of the regeneration channel through the regeneration air port Z. The high-temperature regeneration air reheats and heats the airflow on the air outlet side of the secondary evaporator in the reheating section, so that the air supply temperature is within the target temperature range. This design uses the high-temperature regeneration air as the heat source for air supply reheating, assists in adjusting the air supply temperature, and reduces the operating energy consumption of the air conditioning unit.

[0065] During the operation of the rotary dehumidifier 4, the main function of the regeneration zone is to regenerate the moisture absorbent in the rotor, that is, to desorb the moisture adsorbed by the rotor so that the rotor can continue to absorb new moisture. When the outdoor fresh air is heated, its temperature and humidity conditions change, usually the temperature will increase and the relative humidity will decrease. Then, the high-temperature and low-humidity air is sent to the regeneration zone to contact the moisture absorbent in the rotor. Under high temperature conditions, the moisture absorbed in the rotor is desorbed and enters the regeneration air, and the humidity of the regeneration air will increase significantly. The unfiltered high-humidity regeneration air mixed into the air supply channel will affect the humidity and quality of the air supply. Therefore, in the preferred solution, the reheat section is equipped with a reheat heat exchanger 7, which is provided with a regeneration air heat exchange pipeline and a supply air heat exchange pipeline. The mixed air flow sent out by the secondary evaporator 6 passes through the supply air heat exchange pipeline, and the regeneration air sent out by the regeneration air port Z is discharged to the outside through the regeneration air heat exchange pipeline. The mixed air flow and the regeneration air exchange heat in the reheat heat exchanger 7, the mixed air flow absorbs heat and heats up, and then flows to the outlet of the supply air channel. The purpose of designing the reheat heat exchanger is to recycle the heat of the regeneration air and prevent the regeneration air from affecting the humidity and quality of the supply air flow.

[0066] Since the air flow in the air supply channel has undergone dehumidification and multiple cooling, the humidity of the air supply flow may be too low. In order to accurately adjust the humidity of the air supply flow, a humidifier 8 is also installed in the air supply channel. The humidifier 8 is located on the air outlet side of the reheat heat exchanger 7. When humidification is needed, the humidifier 8 is turned on to ensure that the temperature and humidity of the air flowing out of the air outlet of the air supply channel meet the user's needs.

[0067] It should be understood that the primary mixed return air port H2, the secondary mixed return air port H3, and the pre-cooling return air port H1 mentioned above are all equipped with air valves capable of adjusting the opening. Since the regeneration air has two directions, one is discharged to the outside and the other is entered into the reheat heat exchanger 7, a proportional valve 10 can be installed at the air outlet of the regeneration channel to adjust the flow of the regeneration air through the proportional valve 10. In addition, the pre-cooling heat exchanger 2 and the reheat heat exchanger 7 mentioned above can select a heat exchanger with two sets of heat exchange pipelines, including but not limited to a plate heat exchanger.

[0068] In order to improve the air supply quality, multi-stage filters can also be installed in the air supply channel. For example, an air filter 1 is installed at the air inlet of the air supply channel or the air inlet side of the precooling heat exchanger 2, and a chemical filter 5 is installed between the air outlet side of the rotary dehumidifier 4 and the air inlet side of the secondary evaporator 6. In actual application, the number and position of the filters can be designed according to specific needs, and the present invention does not impose any special restrictions on this.

[0069] In the best embodiment of the present invention, the air conditioning unit is designed with a primary mixing return air inlet H2, a secondary mixing return air inlet H3, a precooling return air inlet H1 and a regeneration air inlet Z to achieve efficient and energy-saving operation of return air cold recovery and regeneration air heat recovery.

[0070] like Figure 4 As shown, the present invention also proposes a control method for an air-conditioning unit, which is applied to the above-mentioned air-conditioning unit, and the control method includes:

[0071] Detect the actual air supply temperature of the air supply channel;

[0072] Compare the actual supply air temperature with the target temperature range;

[0073] When the actual supply air temperature is higher than the target temperature range, it means that the temperature of the mixed air flow on the air inlet side of the secondary evaporator is too high, resulting in the temperature of the mixed air flow failing to drop to an appropriate level after passing through the secondary evaporator. At this time, the air valve opening of the primary mixed return air port H2 is reduced, and the air valve opening of the secondary mixed return air port H3 is increased, so that the return air to the low-temperature room on the air inlet side of the secondary evaporator increases, effectively reducing the temperature of the mixed air flow on the air inlet side of the secondary evaporator.

[0074] When the actual supply air temperature is lower than the target temperature range, it means that the mixed air temperature on the air inlet side of the secondary evaporator is too low, causing the mixed air temperature to drop too much after passing through the secondary evaporator. At this time, the air valve opening of the primary mixed return air port H2 is increased, and the air valve opening of the secondary mixed return air port H3 is reduced. The return air sent to the low-temperature room on the air outlet side of the primary evaporator increases, effectively increasing the mixed air temperature on the air inlet side of the secondary evaporator.

[0075] When the actual supply air temperature is within the target temperature range, the air valve opening of the primary mixing return air outlet H2 and the air valve opening of the secondary mixing return air outlet H3 remain unchanged.

[0076] By real-time monitoring of the actual supply air temperature of the air supply channel and comparing it with the target temperature range, the air valve openings of the primary mixed return air outlet H2 and the secondary mixed return air outlet H3 are quickly responded to and adjusted so that the actual supply air temperature is stabilized within the target temperature range.

[0077] like Figure 5 As shown, on the basis of introducing the indoor return air into the primary mixed return air outlet H2 and the secondary mixed return air outlet H3, some embodiments of the present invention are also designed with precooling control logic, and the specific process is as follows:

[0078] Detecting the actual supply air temperature of the supply air duct and the actual return air temperature of the return air duct;

[0079] Analyze the changing status of actual supply air temperature and actual return air temperature;

[0080] When the actual supply air temperature fluctuates, the air valve opening of the pre-cooling return air outlet H1 is adjusted according to the actual supply air temperature. By changing the air valve opening, the fresh air temperature on the air inlet side of the primary evaporator is adjusted to stabilize the actual supply air temperature and improve indoor comfort.

[0081] When the actual return air temperature fluctuates and the actual supply air temperature is stable, the air valve opening of the pre-cooling return air outlet H1 is adjusted according to the actual return air temperature. By changing the air valve opening, the cooling capacity supplied by the pre-cooling heat exchanger is adjusted to keep the actual supply air temperature stable and ensure indoor comfort.

[0082] When the actual supply air temperature and the actual return air temperature are both stable, the opening of the air valve of the pre-cooling return air port H1 remains unchanged.

[0083] By real-time monitoring of the actual supply air temperature of the supply air duct and the actual return air temperature of the return air duct, the unit can dynamically adjust the opening of the air valve of the pre-cooling return air outlet H1, thereby achieving the effect of stabilizing the supply air temperature and improving the temperature control reliability of the air conditioning unit.

[0084] In some feasible embodiments, analyzing the change state of the actual supply air temperature and the actual return air temperature includes:

[0085] Determine whether the actual supply air temperature is within the target temperature range. If so, the actual supply air temperature is stable; if not, the actual supply air temperature fluctuates.

[0086] Determine whether the actual return air temperature is within the target temperature range. If so, the actual return air temperature is stable; if not, the actual return air temperature fluctuates.

[0087] By judging whether the actual supply air temperature and the actual return air temperature are within the target temperature range, the actual current temperature situation can be better reflected, ensuring that the supply air temperature is always maintained within the set target range and the indoor environment remains in a low temperature and low humidity state for a long time.

[0088] Specifically, the adjustment methods of the pre-cooling return air outlet H1 are divided into the following two types:

[0089] The first method is to adjust the air valve opening of the pre-cooling return air outlet H1 according to the actual supply air temperature, and compare the actual supply air temperature with the target temperature range. When the actual supply air temperature is higher than the target temperature range, the air valve opening of the pre-cooling return air outlet H1 is increased, and more low-temperature indoor return air passes through the pre-cooling heat exchanger 2, thereby increasing the amount of cold air supplied to the outdoor fresh air to reduce the supply air temperature; when the actual supply air temperature is lower than the target temperature range, the air valve opening of the pre-cooling return air outlet H1 is reduced, and the low-temperature indoor return air passing through the pre-cooling heat exchanger 2 is reduced, thereby reducing the amount of cold air supplied to the outdoor fresh air to increase the supply air temperature.

[0090] The second method is to adjust the air valve opening of the pre-cooling return air outlet H1 according to the actual return air temperature, and compare the actual return air temperature with the target temperature range. When the actual return air temperature is higher than the target temperature range, it means that the actual return air temperature is too high and the cold recovery efficiency is reduced. The air valve opening of the pre-cooling return air outlet H1 is reduced, and the low-temperature indoor return air passing through the pre-cooling heat exchanger 2 is reduced; when the actual return air temperature is lower than the target temperature range, it means that the actual return air temperature is too low and the cold recovery efficiency is increased. The air valve opening of the pre-cooling return air outlet H1 is increased, and more low-temperature indoor return air passes through the pre-cooling heat exchanger 2.

[0091] It should be understood that since the pre-cooling return air outlet H1, the primary mixed return air outlet H2 and the secondary mixed return air outlet H3 are all connected to the return air duct, adjusting the air valve opening of the pre-cooling return air outlet H1 will affect the return air volume of the primary mixed return air outlet H2 and the secondary mixed return air outlet H3. Therefore, after each adjustment of the air valve during the control process, the indoor return air will be redistributed to the pre-cooling return air outlet H1, the primary mixed return air outlet H2 and the secondary mixed return air outlet H3, and the supply air temperature is adjusted through the joint cooperation of the three return air outlets.

[0092] like Figure 6 As shown, based on the primary mixed return air outlet H2, the secondary mixed return air outlet H3 and the pre-cooling return air outlet H1, some embodiments of the present invention are also designed with reheat control logic, and the specific process is as follows:

[0093] Detect the actual air supply temperature of the air supply channel;

[0094] Compare the actual supply air temperature with the target temperature range;

[0095] When the actual air supply temperature is higher than the target temperature range, it means that the heat supplied to the mixed air flow by the reheat heat exchanger is too large. At this time, the regeneration air volume of the regeneration air port Z is reduced (the proportional valve 10 is opened to increase), which effectively reduces the mixed air flow temperature on the outlet side of the reheat heat exchanger.

[0096] When the actual air supply temperature is lower than the target temperature range, it means that the heat supplied to the mixed air flow by the reheat heat exchanger is too small. At this time, the regeneration air volume of the regeneration air port Z is increased (the proportional valve 10 is reduced) to effectively increase the mixed air flow temperature on the outlet side of the reheat heat exchanger.

[0097] When the actual supply air temperature is within the target temperature range, the regeneration air volume of the regeneration air outlet Z remains unchanged.

[0098] Since the reheat heat exchanger is located on the air outlet side of the secondary evaporator, the mixed air flow will pass through the reheat heat exchanger to adjust the temperature before being sent out of the air supply channel. The heat supply of the reheat heat exchanger will directly affect the actual supply air temperature. Therefore, the actual supply air temperature is compared with the target temperature range, and the regeneration air volume is adjusted according to the comparison result to achieve the effect of accurately controlling the supply air temperature.

[0099] It should be understood that, in this embodiment, the temperature status of the supply air duct and the return air duct is monitored in real time, and then the return air volume and the regeneration air volume are adjusted in conjunction to achieve rapid and precise control of the supply air temperature, maximize the recovery and utilization of the coldness of the indoor return air and the heat of the regeneration air, enable the air-conditioning unit to operate with high efficiency and energy conservation, and ensure that the indoor environment remains in a low temperature and low humidity state for a long time.

[0100] In order to improve the control accuracy, the preferred solution is to detect the air flow temperature at the air outlet of the air supply channel as the actual air supply temperature, and detect the air flow temperature at the air inlet of the return air channel as the actual return air temperature. In addition, each time after detecting a new actual supply air temperature and actual return air temperature, the unit will re-analyze the operating status and determine the adjustment action of each valve component. The air valve and proportional valve mentioned above can adjust the opening according to a fixed step or a fixed ratio. The present invention does not impose any special restrictions on the specific adjustment form of the increase or decrease of the valve component opening.

[0101] It should be noted that the terms used above are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. When the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof. The order of execution of actions, steps, etc. in the devices and methods shown in the specification and the accompanying drawings can be implemented in any order as long as there is no special explicit limitation on the order and the output of the previous processing is not used in the subsequent processing. Similar terms of order used for the convenience of description do not mean that they must be implemented in such an order.

[0102] Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, such techniques, methods, and apparatus should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limiting. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following figures, and therefore, once an item is defined in one figure, it does not need to be further discussed in subsequent figures.

[0103] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. Air conditioning unit, including: An air supply channel and a return air channel connected to the indoor room, wherein the air supply channel is equipped with a primary evaporator, a rotary dehumidifier adsorption zone, and a secondary evaporator distributed in sequence along the air supply direction; it is characterized in that the air supply channel is provided with a primary mixing return air port and a secondary mixing return air port connected to the return air channel, the primary mixing return air port is located between the air outlet side of the primary evaporator and the air inlet side of the rotary dehumidifier adsorption zone, and the secondary mixing return air port is located between the air outlet side of the rotary dehumidifier adsorption zone and the air inlet side of the secondary evaporator.

2. The air conditioning unit according to claim 1, characterized in that: The air supply channel is also provided with a pre-cooling section located at the air inlet side of the primary heat exchanger, and the pre-cooling section is connected to the return air channel through a pre-cooling return air port.

3. The air conditioning unit according to claim 2, characterized in that: The precooling section is equipped with a precooling heat exchanger, and the precooling heat exchanger is provided with a return air heat exchange pipeline for circulating indoor return air. The indoor return air sent out from the precooling return air outlet is discharged outdoors through the return air heat exchange pipeline.

4. The air conditioning unit according to any one of claims 1 to 3, characterized in that: The air conditioning unit further comprises: a regeneration channel, in which a regeneration wind heating device and a rotary dehumidifier regeneration zone are installed, which are sequentially distributed along the regeneration wind direction; The air supply channel is also provided with a reheating section located at the air outlet side of the secondary evaporator, and the reheating section is connected to the air outlet end of the regeneration channel through a regeneration air port.

5. The air conditioning unit according to claim 4, characterized in that: The reheat section is equipped with a reheat heat exchanger, and the reheat heat exchanger is provided with a regeneration air heat exchange pipeline for circulating regeneration air. The regeneration air delivered from the regeneration air outlet is discharged outdoors through the regeneration air heat exchange pipeline.

6. The air conditioning unit according to claim 5, characterized in that: A humidifier is also installed in the air supply channel, and the humidifier is located on the air outlet side of the reheat heat exchanger.

7. A control method for an air conditioning unit, the control method being applied to the air conditioning unit according to any one of claims 1 to 6, characterized in that: The control method comprises: detecting an actual air supply temperature of the air supply channel; comparing the actual supply air temperature with a target temperature range; When the actual supply air temperature is higher than the target temperature range, the air valve opening of the primary mixed return air outlet is reduced, and the air valve opening of the secondary mixed return air outlet is increased; When the actual supply air temperature is lower than the target temperature range, increasing the air valve opening of the primary mixed return air outlet and decreasing the air valve opening of the secondary mixed return air outlet; When the actual supply air temperature is within the target temperature range, the air valve opening of the primary mixing return air outlet and the air valve opening of the secondary mixing return air outlet are maintained unchanged.

8. The control method according to claim 7, characterized in that: The control method further comprises: Detecting an actual supply air temperature of the air supply channel and an actual return air temperature of the return air channel; Analyzing the change status of the actual supply air temperature and the actual return air temperature; When the actual supply air temperature fluctuates, the opening of the air valve of the pre-cooling return air outlet is adjusted according to the actual supply air temperature; When the actual return air temperature fluctuates and the actual supply air temperature is stable, adjusting the opening of the air valve of the pre-cooling return air outlet according to the actual return air temperature; When the actual supply air temperature and the actual return air temperature are both stable, the opening of the air valve of the pre-cooling return air outlet remains unchanged.

9. The control method according to claim 8, characterized in that: Analyzing the change state of the actual supply air temperature and the actual return air temperature includes: Determine whether the actual air supply temperature is within the target temperature range, if so, the actual air supply temperature is stable, if not, the actual air supply temperature fluctuates; It is determined whether the actual return air temperature is within the target temperature range. If so, the actual return air temperature is stable; if not, the actual return air temperature fluctuates.

10. The control method according to claim 8, characterized in that: Adjusting the air valve opening of the pre-cooling return air outlet according to the actual supply air temperature includes: comparing the actual supply air temperature with a target temperature range; When the actual supply air temperature is higher than the target temperature range, increasing the opening of the air valve of the pre-cooling return air outlet; When the actual supply air temperature is lower than the target temperature range, the air valve opening of the pre-cooling return air outlet is reduced.

11. The control method according to claim 8, characterized in that: Adjusting the air valve opening of the pre-cooling return air outlet according to the actual return air temperature includes: comparing the actual return air temperature with a target temperature range; When the actual return air temperature is higher than the target temperature range, reducing the air valve opening of the pre-cooling return air outlet; When the actual return air temperature is lower than the target temperature range, the air valve opening of the pre-cooling return air outlet is increased.

12. The control method according to claim 7, characterized in that: The control method further comprises: detecting an actual air supply temperature of the air supply channel; comparing the actual supply air temperature with a target temperature range; When the actual air supply temperature is higher than the target temperature range, reducing the regeneration air volume of the regeneration air outlet; When the actual air supply temperature is lower than the target temperature range, increasing the regeneration air volume of the regeneration air outlet; When the actual supply air temperature is within the target temperature range, the regeneration air volume of the regeneration air outlet remains unchanged.

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