Multi-cold-source heat recovery constant air volume constant temperature and humidity fresh air machine

Abstract

The application discloses a multi-cold-source heat recovery constant air volume constant temperature and constant humidity fresh air machine, which comprises a fresh air system, an exhaust air system, a total heat exchanger, a first compressor system loop, a second compressor system loop and an air-water heat exchanger. The air-water heat exchanger is used for being automatically opened when the humidity of the fresh air entering the room is greater than the set humidity, so that external cooling water is introduced to condense and dehumidify the passing fresh air. The first compressor system loop is used for further condensing and dehumidifying the passing fresh air through a first evaporator. The second compressor system loop is used for heating the fresh air with lower temperature after twice condensation and cooling through an air-cooled heat recovery condenser, and further reducing the temperature of the water inlet through the heat exchange between a second evaporator and the water inlet of the air-water heat exchanger to improve the condensing and dehumidifying effect. The system can effectively guarantee the dehumidifying effect, so that the dehumidifying effect is not affected by the temperature change of the external cooling water, and the constant humidity purpose is achieved.

Description

Technical Field

[0001] This invention relates to the field of fresh air fan technology, and in particular, to a fresh air fan with multi-cold source heat recovery, constant air volume, constant temperature and humidity. Background Technology

[0002] Existing conventional fresh air systems are listed below. Figure 1 As shown, it mainly includes an exhaust outlet ①, an exhaust fan ②, a fresh air fan ③, a high-efficiency filter ④, a fresh air outlet ⑤, a fresh air inlet ⑥, a coarse filter ⑦, a medium-efficiency filter ⑧, a heat recovery device ⑨, and an exhaust inlet ⑩. During operation, the fresh air fan ③ draws outdoor air from the fresh air inlet ⑥, through the coarse filter ⑦, the medium-efficiency filter ⑧, and the heat recovery device ⑨, removing PM2.5 before discharging it indoors. Simultaneously, the exhaust fan ② draws indoor air from the exhaust inlet ⑩ and out through the exhaust outlet ①. The fresh air supplied to the room and the exhaust air drawn to the outside undergo heat recovery at the heat recovery device ⑨ inside the machine.

[0003] This fresh air system can purify indoor air, expel polluted indoor air, and maintain indoor oxygen concentration, but it cannot regulate indoor temperature and humidity, and the airflow will decrease when the filter becomes clogged. Summary of the Invention

[0004] This invention provides a multi-cold source heat recovery constant air volume constant temperature and humidity fresh air unit to solve the technical problem that existing fresh air units cannot regulate indoor humidity.

[0005] The technical solution adopted in this invention is as follows: A multi-source heat recovery constant air volume, constant temperature and humidity fresh air unit includes: a fresh air system, an exhaust system, a total heat exchanger, a primary compressor system loop, a secondary compressor system loop, and an air-to-water heat exchanger. The air-to-water heat exchanger is installed in the fresh air system. The primary compressor system loop includes a primary evaporator installed in the fresh air system. The secondary compressor system loop includes an air-cooled heat recovery condenser installed in the fresh air system and a secondary evaporator connected to the water inlet of the air-to-water heat exchanger for heat exchange. The fresh air system is used to introduce outdoor fresh air, filter it, and then introduce it into the total heat exchanger for heat exchange with the exhaust air introduced from the exhaust system, filtered, and then introduced into the total heat exchanger. The fresh air system also allows the heat-exchanged fresh air to sequentially pass through the air-to-water heat exchanger, the primary evaporator, and the air-cooled heat recovery condenser. The exhaust system is used to discharge the heat-exchanged air into the room. The air-water heat exchanger is used to automatically turn on when the humidity of the incoming fresh air is greater than the system set humidity, so as to introduce external cooling water to condense and dehumidify the incoming fresh air. The No. 1 compressor system loop is used to automatically turn on when the humidity of the incoming fresh air is still greater than the system set humidity after the air-water heat exchanger is turned on, so as to further condense and dehumidify the incoming fresh air through the No. 1 evaporator. The No. 2 compressor system loop is used to automatically turn on after the No. 1 compressor system loop is turned on, so as to heat the fresh air with a lower temperature after two condensation and cooling cycles through the air-cooled heat recovery condenser, and to exchange heat with the inlet water of the air-water heat exchanger through the No. 2 evaporator to further reduce the inlet water temperature and improve the condensation and dehumidification effect.

[0006] Furthermore, the multi-source heat recovery constant air volume constant temperature and humidity fresh air unit also includes a fresh air humidity sensor for measuring the humidity of the incoming fresh air, which is connected to the controller of the fresh air dehumidification system; the second compressor system loop also includes a second compressor, a water-cooled condenser, and a second electronic expansion valve connected in sequence in the loop, and the second compressor, air-cooled heat recovery condenser, water-cooled condenser, second electronic expansion valve, and second evaporator are arranged in sequence along the refrigerant flow direction and connected to form a circulation loop; the multi-source heat recovery constant air volume constant temperature and humidity fresh air unit also includes a condensate drain pipe for discharging the condensate generated during the operation of the air-water heat exchanger and the first evaporator, and at the same time connecting to the water-cooled condenser for heat exchange to recover the internal cooling capacity of the condensate.

[0007] Furthermore, the condensate drain circuit includes a condensate collection tray, a drain pipe connected to the condensate collection tray, a drain lift pump connected to the drain pipe, and a condensate drain nozzle connected to the outlet of the drain pipe; the condensate collection tray is located below the air-water heat exchanger and the No. 1 evaporator; the water-cooled condenser is connected to the drain pipe.

[0008] Furthermore, the No. 1 compressor system loop also includes a No. 1 compressor, a No. 1 condenser, and a No. 1 electronic expansion valve connected in sequence in the loop. The No. 1 compressor, the No. 1 condenser, the No. 1 electronic expansion valve, and the No. 1 evaporator are arranged and connected in sequence along the refrigerant flow direction to form a circulation loop. The No. 1 condenser is set in the exhaust system so that the exhaust air after heat exchange passes through the No. 1 condenser before being discharged to the outside.

[0009] Furthermore, the No. 1 compressor system loop also includes a first inlet temperature sensor and a first outlet temperature sensor connected in sequence in the loop, and the first inlet temperature sensor and the first outlet temperature sensor are respectively located on the inlet side and the outlet side of the No. 1 evaporator, so as to automatically adjust the No. 1 evaporator to maintain the optimal working state through the feedback of the first inlet temperature sensor and the first outlet temperature sensor; the No. 2 compressor system loop also includes a second inlet temperature sensor and a second outlet temperature sensor connected in sequence in the loop, and the second inlet temperature sensor and the second outlet temperature sensor are respectively located on the inlet side and the outlet side of the No. 2 evaporator, so as to automatically adjust the No. 2 evaporator to maintain the optimal working state through the feedback of the second inlet temperature sensor and the second outlet temperature sensor.

[0010] Furthermore, the multi-cold-source heat recovery constant air volume constant temperature and humidity fresh air unit also includes a humidifier module installed in the fresh air system, a water inlet pipe connected to the humidifier module to introduce external water, and a water inlet solenoid valve installed in the water inlet pipe; the humidifier module is located upstream of the air-water heat exchanger, and the humidifier module has multiple ultrasonic humidifiers to atomize the incoming water into ultra-fine water mist under the action of multiple ultrasonic humidifiers, and then mix it with the incoming fresh air before entering the air-water heat exchanger together.

[0011] Furthermore, the air-water heat exchanger also includes a proportional two-way valve connected to its inlet water circuit. The air-water heat exchanger is also used to automatically open after the humidifier module is turned on to introduce external hot water. The multi-cold source heat recovery constant air volume constant temperature and humidity fresh air unit also includes a fresh air temperature sensor for measuring the temperature of the fresh air entering the room. The opening of the proportional two-way valve of the air-water heat exchanger is adjusted accordingly based on the fresh air temperature feedback from the fresh air temperature sensor to maintain a constant fresh air temperature.

[0012] Furthermore, the fresh air system also includes a fresh air inlet, a fresh air coarse filter, a fresh air high-efficiency filter, a fresh air fan, and a fresh air outlet arranged sequentially along the fresh air intake direction. The fresh air high-efficiency filter is located upstream of the total heat exchanger, and the fresh air fan is located near the fresh air outlet. The exhaust system also includes an exhaust air inlet, an exhaust air coarse filter, an exhaust fan, and an exhaust air outlet arranged sequentially along the exhaust direction. The coarse filter is located upstream of the total heat exchanger, and the exhaust fan is located near the exhaust air outlet.

[0013] Furthermore, the fresh air system also includes a fresh air flow equalizer installed between the fresh air high-efficiency filter and the total heat exchanger, and a fresh air velocity sensor connected to the fresh air flow equalizer; the exhaust system also includes an exhaust air flow equalizer installed between the exhaust air coarse filter and the total heat exchanger, and an exhaust air velocity sensor connected to the exhaust air flow equalizer.

[0014] Furthermore, the multi-source heat recovery constant air volume constant temperature and humidity fresh air unit also includes a fan casing; the fresh air system, exhaust system, total heat exchanger, No. 1 compressor system circuit, No. 2 compressor system circuit and air-water heat exchanger are all installed inside the fan casing.

[0015] The present invention has the following beneficial effects: When the multi-cold-source heat recovery constant air volume constant temperature and humidity fresh air unit of this invention is working, the fresh air system filters outdoor air and first flows through a total heat exchanger to exchange heat with the exhaust air introduced by the exhaust system and filtered before being introduced into the total heat exchanger. Then, the fresh air system sequentially passes the heat-exchanged fresh air through an air-to-water heat exchanger, an evaporator, and an air-cooled heat recovery condenser before being sent indoors. At the same time, the exhaust system also discharges the heat-exchanged exhaust air outdoors. When the absolute humidity of the air supplied to the room is higher than the system set value, the system automatically turns on the air-to-water heat exchanger, allowing external chilled water (which can be chilled water from a centralized cooling system or chilled water provided by a combined heat and water supply system) to enter from the inlet of the air-to-water heat exchanger and flow out from the outlet of the air-to-water heat exchanger, thus cooling and dehumidifying the air supplied to the room. When the absolute humidity of the incoming indoor air is still higher than the system set value, the No. 1 compressor system loop automatically starts. The refrigerant evaporates and absorbs heat in the No. 1 evaporator, further dehumidifying the air that has been dehumidified by the air-water heat exchanger. At this time, due to the two-stage refrigeration and dehumidification by the air-water heat exchanger and the No. 1 evaporator, the fresh air temperature is very low, requiring heating. At this point, the No. 2 compressor system loop starts, and the refrigerant condenses and releases heat in the air-cooled heat recovery condenser, heating the low-temperature fresh air that has undergone two-stage refrigeration and dehumidification by the air-water heat exchanger and the No. 1 evaporator. Simultaneously, according to the thermodynamic principles of the refrigeration cycle, the lower the condensing temperature, the better the condenser's heat dissipation effect, the higher the refrigeration cycle efficiency, and the lower the required energy consumption. In this application, the air that has undergone two-stage refrigeration by the air-water heat exchanger and the No. 1 evaporator is used to cool and dissipate heat from the air-cooled heat recovery condenser, resulting in good cooling and heat dissipation effect. Therefore, the No. 2 compressor system loop has a high energy efficiency ratio and low energy consumption. In the No. 2 compressor system loop, the refrigerant is condensed and dissipated by the air-cooled heat recovery condenser before entering the No. 2 evaporator to evaporate. It absorbs heat from the cold water flowing from the inlet of the air-water heat exchanger, cooling the incoming cold water and thus lowering the temperature of the external water source. This further enhances the dehumidification capacity of the air-water heat exchanger. This cycle effectively ensures the dehumidification effect, making it unaffected by changes in the temperature of the incoming cold water, achieving constant humidity. At the same time, the entire No. 2 compressor system loop has extremely low overall energy consumption, effectively saving energy.

[0016] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the figures. Attached Figure Description

[0017] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is a schematic diagram of an existing fresh air system structure; Figure 2 This is a schematic diagram of the structure of a multi-cold source heat recovery constant air volume constant temperature and humidity fresh air unit according to a preferred embodiment of the present invention.

[0018] Explanation of reference numerals in the attached figures: 1. Fresh air inlet; 2. Fresh air coarse filter; 3. Fresh air high-efficiency filter; 4. Fresh air velocity sensor; 5. Fresh air flow equalizer; 6. Total heat exchanger; 7. Humidifier module; 8. Air-water heat exchanger; 9. Water inlet solenoid valve; 10. Humidifier water inlet; 11. Evaporator No. 1; 12. Air-cooled heat recovery condenser; 13. Drain tray; 14. Exhaust air flow equalizer; 15. Exhaust air velocity sensor; 16. Exhaust air coarse filter; 17. Exhaust air inlet; 18. Fresh air outlet; 19. Fresh air fan; 20. Fresh air temperature sensor; 21. Fresh air humidity sensor; 22. Drainage lift pump; 23. First inlet temperature sensor; 24. First outlet temperature sensor; 25. Water-cooled condenser; 26. Condensate drain nozzle; 27. Proportional two-way valve for air-to-water heat exchanger; 28. Inlet water port for air-to-water heat exchanger; 29. ​​Outlet water port for air-to-water heat exchanger; 30. Inlet water temperature sensor for air-to-water heat exchanger; 31. Second evaporator; 32. Second inlet temperature sensor; 33. Second electronic expansion valve; 34. Second compressor; 35. Second outlet temperature sensor; 36. Electronic expansion valve No. 1; 37. Compressor No. 1; 38. Fan casing; 39. Condenser No. 1; 40. Exhaust fan; 41. Exhaust outlet. Detailed Implementation

[0019] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the present invention can be implemented in many different ways as defined and covered below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0020] Those skilled in the art will understand that, unless specifically stated otherwise, the term "comprising" as used in this specification means the presence of the stated features, integers, steps, operations, components, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, components, and / or combinations thereof. It should be understood that when we say a component is "connected" to another component, it can be directly connected to the other component or connected via an intermediate component. The term "and / or" as used herein includes all or any unit and all combinations of one or more associated listed items. The terms "first" and "second," etc., in this specification and claims are used to distinguish different objects, not to describe a particular order.

[0021] Reference Figure 2 A preferred embodiment of the present invention provides a multi-source heat recovery constant air volume constant temperature and humidity fresh air unit, comprising: a fresh air system, an exhaust system, a total heat exchanger 6, a first compressor system loop, a second compressor system loop, and an air-to-water heat exchanger 8. The air-to-water heat exchanger 8 is disposed in the fresh air system. The first compressor system loop includes a first evaporator 11 disposed in the fresh air system. The second compressor system loop includes an air-cooled heat recovery condenser 12 disposed in the fresh air system and a second evaporator 31 connected to the air-to-water heat exchanger 8 for heat exchange. The fresh air system is used to introduce outdoor fresh air, filter it, and then introduce it into the total heat exchanger 6 for heat exchange with the exhaust air introduced by the exhaust system, filtered, and then introduced into the total heat exchanger 6. The fresh air system is also used to allow the heat-exchanged fresh air to pass sequentially through the air-to-water heat exchanger 8, the first evaporator 11, and the air-cooled heat recovery condenser 12 before being discharged into the room. The exhaust system is also used to discharge the heat-exchanged exhaust air to the outside. The air-water heat exchanger 8 is automatically turned on when the humidity of the incoming fresh air is greater than the system set humidity, so as to introduce external cooling water to condense and dehumidify the incoming fresh air. The first compressor system loop is automatically turned on when the humidity of the incoming fresh air is still greater than the system set humidity after the air-water heat exchanger 8 is turned on, so as to further condense and dehumidify the incoming fresh air through the first evaporator 11. The second compressor system loop is automatically turned on after the first compressor system loop is turned on, so as to heat the fresh air with a lower temperature after two condensation coolings through the air-cooled heat recovery condenser 12, and to exchange heat with the inlet water of the air-water heat exchanger 8 through the second evaporator 31 to further reduce the inlet water temperature and improve the condensation and dehumidification effect.

[0022] When the multi-cold-source heat recovery constant air volume constant temperature and humidity fresh air unit of the present invention is working, the fresh air system filters the outdoor air and first introduces it into the total heat exchanger 6 to exchange heat with the exhaust air introduced by the exhaust system and filtered before being introduced into the total heat exchanger 6. Then, the fresh air system sequentially passes the heat-exchanged fresh air through the air-to-water heat exchanger 8, the first evaporator 11, and the air-cooled heat recovery condenser 12 before being discharged into the room. At the same time, the exhaust system also discharges the heat-exchanged exhaust air to the outside. When the absolute humidity of the air supplied to the room is higher than the system set value, the system automatically turns on the air-to-water heat exchanger 8, allowing external cold water (which can be cold water from centralized cooling or cold water provided by a heat pump dual-supply system) to enter the air-to-water heat exchanger 8 through the inlet port 28, enter the air-to-water heat exchanger 8, and then flow out through the outlet port 29 of the air-to-water heat exchanger 8, thus cooling and dehumidifying the air supplied to the room. When the absolute humidity of the incoming indoor air is still higher than the system set value, the No. 1 compressor system loop automatically starts. The refrigerant evaporates and absorbs heat in the No. 1 evaporator 11, further dehumidifying the air after it has been dehumidified by the air-water heat exchanger 8. At this time, due to the two-stage refrigeration and dehumidification of the air-water heat exchanger 8 and the No. 1 evaporator 11, the temperature of the fresh air is very low, requiring heating. At this time, the No. 2 compressor system loop starts, and the refrigerant condenses and releases heat in the air-cooled heat recovery condenser 12, which heats the low-temperature fresh air after the two-stage refrigeration and dehumidification of the air-water heat exchanger 8 and the No. 1 evaporator 11. At the same time, according to the working principle of the vapor compression refrigeration cycle, the lower the condensation temperature, the less effort the compressor needs to work, that is, the greater the cooling capacity, the less power consumption, and the higher the energy efficiency when the compressor is working. In a water-air dual-condensing system, the lower the air temperature and cooling water temperature, the lower the condensing temperature and the lower the compressor discharge pressure. Consequently, the system's coefficient of performance (COP / EER) will inevitably be higher. (The underlying principle is: the condenser's function is to dissipate heat from the refrigerant; lower air / water temperatures lead to faster and more efficient heat dissipation; the refrigerant condenses more easily, resulting in lower condensing pressure and temperature; the compressor's pressure ratio decreases, requiring less work, thus consuming more power but achieving a greater cooling capacity and a higher COP / EER). Therefore, for every 1°C decrease in condensing temperature, compressor efficiency typically increases by 2%–3%. Around 40°C, the condensing temperature of a regular air conditioning compressor system is below 40°C, and the COP is 2.8. In the system of this invention, after the dual cooling, dehumidification and cooling of the air-water heat exchanger 8 and the No. 1 compressor system, the air temperature will not exceed 10°C. Therefore, the COP can be increased by (40-10)×2=60%. In addition, the condensate (12°C) condensed from the air-water heat exchanger 8 and the No. 1 evaporator 11 is used to dissipate heat to the water-cooled condenser 25, so the COP can be increased by (40-12)×2=56%.In the No. 2 compressor system loop, the refrigerant is condensed and dissipated by the air-cooled heat recovery condenser 12 before entering the No. 2 evaporator 31 to evaporate. It absorbs the heat from the cold water flowing from the water inlet 28 of the air-water heat exchanger, further cooling the external cold water and thus further reducing the temperature of the external water source. This further improves the dehumidification capacity of the air-water heat exchanger 8. This cycle effectively ensures the dehumidification effect, making it unaffected by changes in the temperature of the external cold water, achieving the goal of constant humidity. At the same time, the overall energy consumption of the No. 2 compressor system loop is extremely low, which can effectively save energy.

[0023] Optionally, such as Figure 2 As shown, the multi-source heat recovery constant air volume constant temperature and humidity fresh air unit also includes a fresh air humidity sensor 21 for measuring the humidity of the incoming fresh air. The fresh air humidity sensor 21 is connected to the controller of the fresh air dehumidification system. During operation, outdoor air forms an airflow in the fresh air duct of the fresh air system. The fresh air system detects the humidity data of the incoming indoor air through the fresh air humidity sensor 21, converts it into absolute humidity, and compares it with the system set value. When it is higher than the system set value, the controller automatically starts the air-water heat exchanger 8, the first compressor system loop, the second compressor system loop, etc. The second compressor system loop also includes a second compressor 34, a water-cooled condenser 25, and a second electronic expansion valve 33 connected in sequence in the loop. The second compressor 34, the air-cooled heat recovery condenser 12, the water-cooled condenser 25, the second electronic expansion valve 33, and the second evaporator 31 are arranged in sequence along the refrigerant flow direction and connected to form a circulation loop. The multi-source heat recovery constant air volume constant temperature and humidity fresh air unit also includes a condensate drain circuit to discharge the condensate generated during the operation of the air-water heat exchanger 8 and the No. 1 evaporator 11, while connecting to the water-cooled condenser 25 for heat exchange to recover the internal cooling capacity of the condensate.

[0024] In this optional solution, such as Figure 2As shown, the condensate drain circuit includes a condensate collection tray 13, a drain pipe connected to the condensate collection tray 13, a drain pump 22 connected to the drain pipe, and a condensate drain nozzle 26 connected to the outlet of the drain pipe. The condensate collection tray 13 is located below the air-to-water heat exchanger 8 and the first evaporator 11. The water-cooled condenser 25 is connected to the drain pipe. During operation, when the outdoor air passes through the air-water heat exchanger 8 and the first evaporator 11 for secondary cooling and dehumidification, resulting in a very low fresh air temperature, it needs to be heated. At this time, the second compressor 34 is activated. The refrigerant in the second compressor system is compressed by the second compressor 34 into a high-temperature, high-pressure gas, which heats the low-temperature fresh air after the secondary cooling and dehumidification of the air-water heat exchanger 8 and the first evaporator 11, while also recovering this heat. The refrigerant after heat recovery flows into the water-cooled condenser 25. The condensate produced by the air-water heat exchanger 8 and the first evaporator 11 for cooling and dehumidifying the fresh air is collected by the water tray 13 and sent to the water-cooled condenser 25 by the drain pump 22. The condensate and the water-cooled condenser... The refrigerant in the water-cooled condenser 25 undergoes heat exchange. The condensate carries away the heat from the refrigerant in the water-cooled condenser 25 and is then discharged from the condensate drain 26. The refrigerant in the second compressor system undergoes two-stage condensation and heat dissipation through the air-cooled heat recovery condenser 12 and the water-cooled condenser 25 to become a low-temperature, high-pressure liquid refrigerant. After being throttled by the second electronic expansion valve 33, it evaporates in the second evaporator 31, absorbing the heat from the cold water flowing from the air-water heat exchanger inlet 28. This cools the incoming cold water, further reducing the temperature of the external water source and thus improving the dehumidification capacity of the air-water heat exchanger 8. This cycle effectively ensures the dehumidification effect, achieves constant humidity, and also saves energy.

[0025] Optionally, such as Figure 2 As shown, the No. 1 compressor system loop also includes a No. 1 compressor 37, a No. 1 condenser 39, and a No. 1 electronic expansion valve 36 connected sequentially in the loop. The No. 1 compressor 37, the No. 1 condenser 39, the No. 1 electronic expansion valve 36, and the No. 1 evaporator 11 are arranged and connected sequentially along the refrigerant flow direction to form a circulation loop. The No. 1 condenser 39 is located in the exhaust system so that the exhaust air after heat exchange passes through the No. 1 condenser 39 before being discharged outdoors. During operation, the refrigerant in the No. 1 compressor system circuit is compressed by the No. 1 compressor 37 into a high-temperature, high-pressure gas. At this time, due to the function of the exhaust system, the indoor air is filtered and then discharged to the outside through the total heat exchanger 6 and the No. 1 condenser 39. An airflow is formed in the exhaust duct, which condenses the high-temperature, high-pressure refrigerant in the No. 1 compressor 37 in the No. 1 condenser 39. After condensation and heat dissipation, the refrigerant changes from a high-temperature, high-pressure gaseous state to a low-temperature, high-pressure liquid refrigerant. Then, it is throttled by the No. 1 electronic expansion valve 36 and evaporates and absorbs heat in the No. 1 evaporator 11, further dehumidifying the air that has been dehumidified by the air-water heat exchanger 8.

[0026] Optionally, such as Figure 2 As shown, the first compressor system loop also includes a first inlet temperature sensor 23 and a first outlet temperature sensor 24 connected sequentially in the loop. The first inlet temperature sensor 23 and the first outlet temperature sensor 24 are respectively located on the inlet side and the outlet side of the first evaporator 11, so as to automatically adjust the first evaporator 11 to maintain the optimal operating state through the feedback of the first inlet temperature sensor 23 and the first outlet temperature sensor 24. The second compressor system loop also includes a second inlet temperature sensor 32 and a second outlet temperature sensor 35 connected sequentially in the loop. The second inlet temperature sensor 32 and the second outlet temperature sensor 35 are respectively located on the inlet side and the outlet side of the second evaporator 31, so as to automatically adjust the second evaporator 31 to maintain the optimal operating state through the feedback of the second inlet temperature sensor 32 and the second outlet temperature sensor 35.

[0027] During operation, the system calculates the actual superheat of the No. 1 compressor system circuit by subtracting the temperature value from the temperature value of the first outlet temperature sensor 24 from the temperature value of the first inlet temperature sensor 23. The actual superheat is compared with the set superheat, and the opening of the No. 1 electronic expansion valve 36 is controlled based on the actual superheat of the No. 1 compressor system circuit, thereby regulating the refrigerant flow rate of the No. 1 compressor system circuit. When the actual superheat of the No. 1 compressor system circuit is greater than the set superheat, it indicates that the refrigerant flow rate is too low and needs to be increased. The No. 1 electronic expansion valve 36 then adds 5 pulses. To adjust the refrigerant flow in the No. 1 compressor system circuit, increase the flow rate every 3 minutes until the actual superheat equals the set superheat. If the actual superheat of the No. 1 compressor system circuit is less than the set superheat, it indicates that the refrigeration system flow rate is too high and needs to be reduced. The No. 1 electronic expansion valve 36 will reduce the flow rate by 5 pulses, thus reducing the refrigerant flow rate in the No. 1 compressor system circuit. This process is repeated every 3 minutes until the actual superheat equals the set superheat. Through intelligent adjustment, the No. 1 compressor system circuit can be precisely kept at its optimal dehumidification level. Simultaneously, the system calculates the actual superheat of the second compressor system circuit by subtracting the temperature value from the second outlet temperature sensor 35 based on the temperature value of the second inlet temperature sensor 32. This actual superheat is compared to the set superheat, and the opening of the second electronic expansion valve 33 is controlled based on the actual superheat of the second compressor system circuit, thereby regulating the refrigerant flow rate of the second compressor system circuit. When the actual superheat of the second compressor system circuit is greater than the set superheat, it indicates that the refrigeration system flow rate is too low and needs to be increased. The second electronic expansion valve 33 then adds 5 pulses, thus increasing the refrigerant flow rate of the second compressor system. The refrigerant flow rate of the first compressor system loop is adjusted every 3 minutes until the actual superheat equals the set superheat. When the actual superheat of the second compressor system loop is less than the set superheat, it indicates that the refrigeration system flow rate is too high and needs to be reduced. The second electronic expansion valve 33 reduces the flow rate by 5 pulses, thus reducing the refrigerant flow rate of the second compressor system loop. This process is repeated every 3 minutes until the actual superheat equals the set superheat. Through intelligent adjustment, the second compressor system loop can be precisely maintained to ensure the best cooling effect, effectively guaranteeing the dehumidification effect and achieving constant humidity.

[0028] Optionally, such as Figure 2 As shown, the multi-source heat recovery constant air volume constant temperature and humidity fresh air unit also includes a humidifier module 7 installed in the fresh air system, a water inlet pipe connected to the humidifier module 7 to introduce external water, and a water inlet solenoid valve 9 installed in the water inlet pipe. The humidifier module 7 is located upstream of the air-water heat exchanger 8, and the humidifier module 7 has multiple ultrasonic humidifiers to atomize the incoming water into ultrafine particles under the action of the multiple ultrasonic humidifiers, which then mix with the incoming fresh air and enter the air-water heat exchanger 8 together.

[0029] During operation, the system compares the detected fresh air humidity with the set value using the fresh air humidity sensor 21. In summer, when the actual humidity detected by the fresh air humidity sensor 21 is higher than the set humidity, the system dehumidifies using the above method to maintain a constant fresh air humidity. In winter, when the fresh air humidity sensor 21 detects that the fresh air humidity is lower than the set humidity, humidification is required. Currently, there are three types of humidification methods: 1) Steam-type evaporative humidifiers, whose working principle is to heat water to boil and produce... There are three main types of humidifiers: 1. Steam humidifiers: Advantages: large humidification capacity, fast effect; Disadvantages: high power consumption, high electricity consumption, high machine surface temperature. 2. Cold evaporation humidifiers (mist-free type): The working principle is that air flows through a moistened filter via a fan, and the water evaporates naturally without producing visible water mist. Disadvantages: The filter needs to be replaced regularly, resulting in ongoing costs, and the humidification speed is relatively slow. 3. Ultrasonic humidifiers (mist type): The working principle is that water is atomized into 1-5 micron ultrafine particles through high-frequency oscillation at 1.7MHz, and the water mist is blown out by a fan. Advantages: high humidification efficiency, extremely low energy consumption (only 0.05 kW / 1kg.h); Disadvantages: visible white water mist is formed, which condenses into water droplets in the fresh air duct. In summary, these three humidification methods are characterized by high power consumption, small humidification capacity, and the formation of water droplets, making them unsuitable for the current humidification modes of fresh air systems. In this invention system, a humidifier module 7 is installed before the air-to-water heat exchanger 8. Multiple ultrasonic humidifiers are installed on the humidifier module 7. When the actual humidity detected by the fresh air humidity sensor 21 is lower than the set temperature, the water inlet solenoid valve 9 is energized and opened, allowing tap water to enter from the humidifier inlet 10. This water flows through the humidifier module 7, atomizing the water into 1-5 micrometer ultrafine water mist, which then enters the fresh air, thus humidifying it. In winter, when the fresh air needs to be heated, hot water flows in from the air-to-water heat exchanger inlet 28 and flows sequentially through the second evaporator. 31. Water flows out from the air-water heat exchanger outlet 29 after the air-water heat exchanger 8, heating the air-water heat exchanger 8 to raise the temperature of the fresh air. At the same time, the heat from the increased temperature of the air-water heat exchanger 8 can evaporate 1-5 micron ultrafine water mist. Since the 1-5 micron water mist particles are small, only a small amount of heat is needed for secondary evaporation. The evaporated water humidifies the fresh air before it is sent indoors. Thus, the ultrasonic humidification combined with low-temperature thermal evaporation humidification achieves a large humidification capacity and energy-saving humidification, keeping the humidity of the fresh air constant in winter.

[0030] Preferably, such as Figure 2As shown, the air-to-water heat exchanger 8 also includes an air-to-water heat exchanger proportional two-way valve 27 and an air-to-water heat exchanger inlet water temperature sensor 30 connected to its inlet water circuit. The air-to-water heat exchanger 8 is also used to automatically turn on after the humidifier module 7 is turned on to introduce external hot water. The multi-cold source heat recovery constant air volume constant temperature and humidity fresh air unit also includes a fresh air temperature sensor 20 for measuring the temperature of the fresh air entering the room, so as to adjust the opening of the air-to-water heat exchanger proportional two-way valve 27 accordingly based on the fresh air temperature feedback from the fresh air temperature sensor 20, so as to ensure a constant fresh air temperature.

[0031] During operation, the system compares the fresh air temperature detected by the fresh air temperature sensor 20 with the set value. In summer, the external energy supply to the fresh air unit is chilled water. The chilled water flows in from the inlet 28 of the air-to-water heat exchanger, passes through the proportional two-way valve 27, the second evaporator 31, and the air-to-water heat exchanger 8, and then flows out from the outlet 29 of the air-to-water heat exchanger, thereby cooling the fresh air flowing through the air-to-water heat exchanger 8. When the fresh air temperature sensor 20 detects that the fresh air temperature is higher than the set temperature, the system will increase the opening of the proportional two-way valve 27 of the air-to-water heat exchanger, increasing the flow rate of chilled water through the air-to-water heat exchanger 8, thus further cooling the fresh air. The system adjusts the opening of the air-water heat exchanger proportional two-way valve 27 to increase the water flow through the air-water heat exchanger 8, thereby increasing the temperature of the fresh air. In winter, the external energy supply to the fresh air unit is hot water. The hot water flows in from the inlet 28 of the air-water heat exchanger, passes through the proportional two-way valve 27 of the air-water heat exchanger, the second evaporator 31, and the air-water heat exchanger 8, and then flows out from the outlet 29 of the air-water heat exchanger, thus heating the fresh air flowing through the air-water heat exchanger 8. When the fresh air temperature sensor 20 detects that the fresh air temperature is lower than the set temperature, the system will increase the opening of the proportional two-way valve 27 of the air-water heat exchanger to increase the water flow through the air-water heat exchanger 8 and increase the temperature of the fresh air. Conversely, it will decrease the opening to achieve a constant fresh air temperature in summer / winter.

[0032] Optionally, such as Figure 2 As shown, the fresh air system also includes a fresh air inlet 1, a fresh air coarse filter 2, a fresh air high-efficiency filter 3, a fresh air fan 19, and a fresh air outlet 18 arranged sequentially along the fresh air flow direction. The fresh air high-efficiency filter 3 is located upstream of the total heat exchanger 6, and the fresh air fan 19 is located near the fresh air outlet 18. The exhaust system also includes an exhaust air inlet 17, an exhaust air coarse filter 16, an exhaust fan 40, and an exhaust air outlet 41 arranged sequentially along the exhaust air flow direction. The exhaust air coarse filter 16 is located upstream of the total heat exchanger 6, and the exhaust fan 40 is located near the exhaust air outlet.

[0033] Preferably, such as Figure 2As shown, the fresh air system also includes a fresh air flow equalizer 5 disposed between the fresh air high-efficiency filter 3 and the total heat exchanger 6, and a fresh air velocity sensor 4 connected to the fresh air flow equalizer 5. The exhaust system also includes an exhaust air flow equalizer 14 disposed between the exhaust air coarse filter 16 and the total heat exchanger 6, and an exhaust air velocity sensor 15 connected to the exhaust air flow equalizer 14.

[0034] During operation, the coarse air filter 2 and the high-efficiency air filter 3 will become clogged with outdoor dust after a period of use. Once the filters are clogged, the fresh air volume will decrease even with the fresh air fan speed remaining constant. The system uses the fresh air velocity sensor 4 installed on the fresh air flow equalizer 5 to detect the air velocity in the fresh air duct. Since air volume equals the effective cross-sectional area of ​​the duct outlet multiplied by the average cross-sectional velocity, the actual fresh air volume can be calculated by measuring the average cross-sectional velocity and determining the cross-sectional area of ​​the fresh air duct. This is due to the fresh air flow equalizer. Device 5, after the fresh air flowing through it is evenly distributed, improves the accuracy of the average wind speed data of the fresh air duct cross-section. The control system can then calculate the actual fresh air volume and compare it with the set value. When the fresh air volume is lower than the set volume, the system automatically increases the speed of the fresh air fan to increase the fresh air volume until the fresh air volume equals the set volume. When the fresh air volume is higher than the set volume, the system automatically decreases the speed of the fresh air fan to decrease the fresh air volume until the fresh air volume equals the set volume. At the same time, an exhaust coarse filter 16 is installed in the exhaust duct. After a period of use, the exhaust airflow will decrease due to indoor dust clogging and filter blockage, even with a constant exhaust fan speed. The system uses an exhaust velocity sensor 15 installed on the exhaust flow equalizer 14 to detect the air velocity in the exhaust duct. Since airflow equals the effective cross-sectional area of ​​the duct outlet multiplied by the average cross-sectional velocity, the actual exhaust airflow can be calculated by measuring the average cross-sectional velocity and determining the cross-sectional area of ​​the exhaust duct. Because of the exhaust flow equalizer 14, the exhaust airflow is evenly distributed, improving the efficiency of the exhaust duct cross-section. With accurate average air velocity data, the control system can calculate the actual exhaust air volume and compare it with the set value. When the exhaust air volume is lower than the set air volume, the system automatically increases the speed of the exhaust fan to increase the exhaust air volume until the exhaust air volume equals the set exhaust air volume. When the exhaust air volume is higher than the set air volume, the system automatically decreases the speed of the exhaust fan to decrease the exhaust air volume until the exhaust air volume equals the set exhaust air volume. By effectively controlling the fresh air volume and exhaust air volume, the fresh air volume and exhaust air volume can be freely set, effectively achieving constant air volume for fresh air and exhaust air.

[0035] Furthermore, to ensure indoor air quality and achieve optimal replacement ventilation, a slight positive pressure must be maintained indoors, meaning the fresh air volume is always greater than the exhaust air volume. When the fresh air coarse filter 2 and the fresh air high-efficiency filter 3 become clogged, the system detects a decrease in air velocity through the fresh air speed sensor 4, thereby increasing the speed of the fresh air fan 19 to maintain a constant fresh air volume. However, once the fresh air fan reaches its maximum speed, the fresh air volume cannot be increased further. The system will then dynamically adjust the exhaust air volume according to the maximum fresh air volume. The exhaust air volume will no longer operate according to the original set air volume value, but will track the fresh air volume value. The exhaust air volume will be calculated in real time based on the actual fresh air volume, always maintaining a fresh air volume to exhaust air volume ratio of 10:8. In short, since the fresh air fan reaches its maximum speed, the fresh air coarse filter 2 and the fresh air high-efficiency filter 3 are not replaced. The fresh air volume continuously decreases, and the exhaust air volume also continuously decreases, always maintaining a slight positive pressure indoors, achieving a constant indoor pressure effect.

[0036] Reference Figure 2 The multi-cold source heat recovery constant air volume constant temperature and humidity fresh air unit also includes a fan housing; the fresh air system, exhaust system, total heat exchanger 6, No. 1 compressor system circuit, No. 2 compressor system circuit and air-water heat exchanger 8 are all installed inside the fan housing.

[0037] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A multi-cold-source heat recovery constant air volume constant temperature and humidity fresh air machine, characterized in that, include: Fresh air system, exhaust system, total heat exchanger (6), compressor system loop 1, compressor system loop 2 and air-water heat exchanger (8). The air-water heat exchanger (8) is installed in the fresh air system. The first compressor system circuit includes the first evaporator (11) installed in the fresh air system. The second compressor system circuit includes the air-cooled heat recovery condenser (12) installed in the fresh air system and the second evaporator (31) connected to the inlet water of the air-water heat exchanger (8) for heat exchange. The fresh air system is used to introduce fresh outdoor air and filter it before introducing it into the total heat exchanger (6) to exchange heat with the exhaust air introduced by the exhaust system and filtered before being introduced into the total heat exchanger (6). The fresh air system is also used to allow the fresh air after heat exchange to pass through the air-water heat exchanger (8), the No. 1 evaporator (11), and the air-cooled heat recovery condenser (12) in sequence before being discharged into the room. The exhaust system is also used to allow the exhaust air after heat exchange to be discharged to the outside. The air-water heat exchanger (8) is automatically turned on when the humidity of the fresh air entering the room is greater than the system set humidity, so as to introduce external cooling water to condense and dehumidify the passing fresh air. The first compressor system loop is automatically turned on when the humidity of the fresh air entering the room is still greater than the system set humidity after the air-water heat exchanger (8) is turned on, so as to further condense and dehumidify the passing fresh air through the first evaporator (11). The second compressor system loop is automatically turned on after the first compressor system loop is turned on, so as to heat the fresh air with a lower temperature after two condensation and cooling through the air-cooled heat recovery condenser (12), and exchange heat with the inlet water of the air-water heat exchanger (8) through the second evaporator (31) to reduce the inlet water temperature and improve the condensation and dehumidification effect.

2. The multi-cold-source heat recovery constant air volume constant temperature and humidity fresh air unit according to claim 1, characterized in that, The multi-cold source heat recovery constant air volume constant temperature and humidity fresh air unit also includes a fresh air humidity sensor (21) for measuring the humidity of the fresh air entering the room. The fresh air humidity sensor (21) is connected to the controller of the fresh air dehumidification system. The second compressor system loop also includes the second compressor (34), water-cooled condenser (25) and second electronic expansion valve (33) connected in sequence in the loop. The second compressor (34), air-cooled heat recovery condenser (12), water-cooled condenser (25), second electronic expansion valve (33) and second evaporator (31) are arranged in sequence along the refrigerant flow direction and connected to form a circulation loop. The multi-source heat recovery constant air volume constant temperature and humidity fresh air unit also includes a condensate drain circuit, which is used to discharge the condensate generated when the air-water heat exchanger (8) and the No. 1 evaporator (11) are working, and at the same time connects to the water-cooled condenser (25) for heat exchange to recover the internal cooling capacity of the condensate.

3. The multi-cold-source heat recovery constant air volume constant temperature and humidity fresh air unit according to claim 2, characterized in that, The condensate drain circuit includes a water collection tray (13) for collecting condensate, a drain pipe connected to the water collection tray (13), a drain lift pump (22) connected to the drain pipe, and a condensate drain nozzle (26) connected to the outlet of the drain pipe. The water receiving tray (13) is located below the air-water heat exchanger (8) and the No. 1 evaporator (11); The water-cooled condenser (25) is connected to the drain pipe.

4. The multi-cold-source heat recovery constant air volume constant temperature and humidity fresh air unit according to claim 2, characterized in that, The No. 1 compressor system loop also includes the No. 1 compressor (37), the No. 1 condenser (39), and the No. 1 electronic expansion valve (36) connected in sequence in the loop. The No. 1 compressor (37), the No. 1 condenser (39), the No. 1 electronic expansion valve (36), and the No. 1 evaporator (11) are arranged and connected in sequence along the refrigerant flow direction to form a circulation loop. The No. 1 condenser (39) is installed in the exhaust system, and the exhaust air is discharged to the outside after passing through the No. 1 condenser (39).

5. The multi-cold-source heat recovery constant air volume constant temperature and humidity fresh air unit according to claim 4, characterized in that, The No. 1 compressor system loop also includes a first inlet temperature sensor (23) and a first outlet temperature sensor (24) connected in sequence in the loop. The first inlet temperature sensor (23) and the first outlet temperature sensor (24) are respectively located on the inlet side and the outlet side of the No. 1 evaporator (11) so as to automatically adjust the No. 1 evaporator (11) to maintain the best working state through the feedback of the first inlet temperature sensor (23) and the first outlet temperature sensor (24). The second compressor system loop also includes a second inlet temperature sensor (32) and a second outlet temperature sensor (35) connected in sequence in the loop. The second inlet temperature sensor (32) and the second outlet temperature sensor (35) are respectively located on the inlet side and the outlet side of the second evaporator (31) so as to automatically adjust the second evaporator (31) to maintain the best working state through the feedback of the second inlet temperature sensor (32) and the second outlet temperature sensor (35).

6. The multi-cold-source heat recovery constant air volume constant temperature and humidity fresh air unit according to claim 2, characterized in that, The multi-cold source heat recovery constant air volume constant temperature and humidity fresh air unit also includes a humidifier module (7) installed in the fresh air system, a water inlet pipe connected to the humidifier module (7) to introduce external water, and a water inlet solenoid valve (9) installed in the water inlet pipe. The humidifier module (7) is located upstream of the air-water heat exchanger (8), and the humidifier module (7) has multiple ultrasonic humidifiers to atomize the incoming water into ultrafine particles under the action of multiple ultrasonic humidifiers, and then mix with the incoming fresh air and enter the air-water heat exchanger (8).

7. The multi-cold-source heat recovery constant air volume constant temperature and humidity fresh air unit according to claim 6, characterized in that, The air-water heat exchanger (8) also includes an air-water heat exchanger proportional two-way valve (27) connected to its inlet water circuit. The air-water heat exchanger (8) is also used to automatically open after the humidifier module (7) is turned on to introduce external hot water. The multi-cold source heat recovery constant air volume constant temperature and humidity fresh air unit also includes a fresh air temperature sensor (20) for measuring the temperature of the fresh air entering the room. The opening degree of the proportional two-way valve (27) of the air-water heat exchanger is adjusted accordingly based on the fresh air temperature fed back by the fresh air temperature sensor (20) to maintain the constant fresh air temperature.

8. The multi-cold-source heat recovery constant air volume constant temperature and humidity fresh air unit according to claim 1, characterized in that, The fresh air system also includes a fresh air inlet (1), a fresh air coarse filter (2), a fresh air high-efficiency filter (3), a fresh air fan (19), and a fresh air outlet (18) arranged sequentially along the fresh air entry direction. The fresh air high-efficiency filter (3) is located upstream of the total heat exchanger (6), and the fresh air fan (19) is located near the fresh air outlet (18). The exhaust system also includes an exhaust inlet (17), an exhaust coarse filter (16), an exhaust fan (40) and an exhaust outlet arranged sequentially along the exhaust direction. The coarse filter is located upstream of the total heat exchanger (6), and the exhaust fan (40) is located near the exhaust outlet.

9. The multi-cold-source heat recovery constant air volume constant temperature and humidity fresh air unit according to claim 8, characterized in that, The fresh air system also includes a fresh air flow equalizer (5) installed between the fresh air high-efficiency filter (3) and the total heat exchanger (6), and a fresh air wind speed sensor (4) connected to the fresh air flow equalizer (5). The exhaust system also includes an exhaust flow equalizer (14) disposed between the exhaust coarse filter (16) and the total heat exchanger (6), and an exhaust wind speed sensor (15) connected to the exhaust flow equalizer (14).

10. The multi-cold-source heat recovery constant air volume constant temperature and humidity fresh air unit according to claim 1, characterized in that, The multi-cold source heat recovery constant air volume constant temperature and humidity fresh air unit also includes a fan casing; The fresh air system, exhaust system, total heat exchanger (6), compressor system loop 1, compressor system loop 2 and air-water heat exchanger (8) are all installed inside the fan casing.

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