VAV air conditioning system based on temperature and humidity separate control technology and operation method

Abstract

The invention discloses a VAV air conditioning system based on the temperature and humidity separate control technology and an operation method.The VAV air conditioning system comprises intelligent fresh air terminals, intelligent air supply terminals, a digital fresh air handling unit and a digital air conditioning unit, the air outlet side of the digital fresh air handling unit is connected with a fresh air header pipe, and the fresh air header pipe is connected with the multiple intelligent fresh air terminals through fresh air branch pipes; the digital air conditioning unit is provided with an air return valve and a fresh air valve, the fresh air valve is connected with a fresh air header pipe, the air return valve is connected with an air return pipe, and the air outlet side of the digital air conditioning unit is connected with the intelligent air supply terminal through an air supply pipe. According to the VAV air conditioning system, fresh air is processed by the digital fresh air handling unit, circulating air is processed by the digital air conditioning unit, the adjusting performance is good, and all-around control over the temperature, the humidity and the air quality is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of application of all-air air conditioning systems in various buildings, and in particular to a VAV air conditioning system based on temperature and humidity separate control technology and an operating method thereof. Background Art

[0002] A VAV air conditioning system regulates indoor temperature by varying the air volume. Unlike constant air volume systems, VAV systems automatically adjust air volume based on changes in indoor load, achieving a balance between energy savings and comfort. Due to its energy-saving, high-efficiency, flexible control, and adaptability, VAV systems are widely used in large buildings such as office buildings, shopping malls, and hotels. They are particularly suitable for locations with large variations in cooling and heating loads and the need for zoning control. However, their inherent shortcomings become apparent in applications with large variations in indoor humidity loads, high indoor air quality requirements, and the need for sufficient fresh air volume, making them difficult to meet.

[0003] There are two types of VAV air conditioning systems in existing civil public buildings: one is that the air conditioning unit takes in fresh air itself, that is, fresh air is introduced from the outside and processed together with return air by the air conditioning unit before being delivered through the terminal air supply device; the other is that fresh air is centrally processed and then sent to the air conditioning unit, where it is processed together with return air and delivered through the terminal air supply device. For the work area corresponding to the air supply terminal, the existing VAV air conditioning system has poor regulation performance and cannot achieve comprehensive control of temperature, humidity and air quality. Summary of the Invention The purpose of the present invention is to provide a VAV air-conditioning system and operating method based on temperature and humidity separate control technology to solve one or more technical problems existing in the prior art and at least provide a beneficial option or create conditions.

[0004] The technical solutions adopted to solve the above technical problems are: The present invention provides a VAV air conditioning system based on temperature and humidity separate control technology, comprising: There are multiple intelligent fresh air terminals; There are multiple intelligent air supply terminals; A digital fresh air unit is provided, wherein the air outlet side of the digital fresh air unit is connected to a fresh air main pipe, and the fresh air main pipe is connected to the plurality of smart fresh air terminals through fresh air branches; A digital air-conditioning unit is provided with at least one, wherein a return air valve and a fresh air valve are provided on the air inlet side of the digital air-conditioning unit, the fresh air valve is connected to the fresh air main pipe, the return air valve is connected to the return air duct, and the air outlet side of the digital air-conditioning unit is connected to multiple intelligent air supply terminals through an air supply duct.

[0005] The VAV air conditioning system of the present invention has the following beneficial effects: The present invention divides the traditional VAV system in which fresh air and return air are jointly processed by one device into two independent systems, namely, the fresh air is processed by the digital fresh air unit and the circulating air is processed by the digital air-conditioning unit. One digital fresh air unit corresponds to one digital air-conditioning unit or one digital fresh air unit corresponds to multiple digital air-conditioning units. When in use, the digital fresh air unit centrally collects and processes the fresh air, and then transports it to each floor or partition by the fresh air main pipe. Part of the fresh air is transported to the work area requiring humidity control and air quality control by each intelligent fresh air terminal, and the other part of the fresh air enters the digital air-conditioning unit and the return air is processed by the digital air-conditioning unit and then transported to the work area of each open space through the intelligent air supply terminal. The intelligent fresh air terminal is arranged on the fresh air branch pipe of the work area, responsible for adjusting the fresh air volume; the intelligent air supply terminal is arranged on the air supply pipe of the work area, responsible for delivering the air from the digital air-conditioning unit to each work area as needed, so that the VAV air-conditioning system has good adjustment performance and realizes all-round control of temperature, humidity and air quality.

[0006] As a further improvement of the above technical solution, the digital fresh air unit includes a fresh air fan for adjusting the supply of fresh air, a fresh air air treatment module for air purification of the fresh air, and a fresh air heat and humidity treatment module for heat and humidity treatment of the fresh air.

[0007] As a further improvement of the above technical solution, the digital air-conditioning unit includes an air-conditioning fan for adjusting the supply amount of air, an air-conditioning air treatment module for air purification of the circulating air, and an air-conditioning heat and moisture treatment module for heat and moisture treatment of the circulating air.

[0008] As a further improvement of the above technical solution, it also includes a digital air supply unit, which is connected between the fresh air main pipe and the multiple smart fresh air terminals. The digital air supply unit includes an air supply fan for adjusting the air supply volume.

[0009] As a further improvement of the above technical solution, the digital air supply unit also includes an air supply heat and moisture treatment module for performing heat and moisture treatment on the supply air.

[0010] As a further improvement of the above technical solution, it also includes an intelligent control system, which includes a fresh air unit control system, a supply air unit control system, and an air conditioning unit control system; The fresh air unit control system includes a fresh air unit intelligent control cabinet, a first air supply pressure sensor, a first air inlet temperature and humidity sensor, a first air supply temperature and humidity sensor, and an air quality sensor connected to the fresh air unit intelligent control cabinet. The fresh air unit intelligent control cabinet is respectively connected to the fresh air fan, the fresh air treatment module, and the fresh air heat and humidity treatment module; The air conditioning unit control system includes an air conditioning unit intelligent control cabinet, a second air supply pressure sensor, a second air inlet temperature sensor, and a second air supply temperature sensor connected to the air conditioning unit intelligent control cabinet, and the air conditioning unit intelligent control cabinet is connected to the air conditioning fan and the air conditioning heat and humidity processing module respectively; The air supply unit control system includes an air supply unit controller and an air duct pressure sensor connected to the air supply unit controller. The air supply unit controller is connected to the air supply fan.

[0011] As a further improvement of the above technical solution, the intelligent fresh air terminal and the intelligent air supply terminal respectively include a wind speed sensor and an air volume adjustment mechanism.

[0012] As a further improvement of the above technical solution, the intelligent fresh air terminal and the intelligent air supply terminal respectively include a wind speed sensor and a terminal fan.

[0013] As a further improvement of the above technical solution, it also includes an intelligent control system, which includes an intelligent terminal control system, and the intelligent terminal control system includes a terminal controller and a sensor group connected to the terminal controller.

[0014] As a further improvement of the above technical solution, the sensor group includes one or more of a VOC sensor, a CO2 sensor, a temperature and humidity sensor, a PM2.5 sensor, and a pressure difference sensor.

[0015] The present invention further provides an operating method, which is applicable to the VAV air conditioning system, and the operating method comprises: Obtain real-time humidity data, real-time air quality data, and real-time temperature data in the working area; According to the comparison between the real-time humidity data and the preset humidity data, the humidity of the working area is adjusted by controlling the flow rate of the intelligent fresh air terminal, the flow rate of the fresh air valve and the heat and moisture processing power of the digital fresh air unit; According to the comparison between the real-time air quality data and the preset air quality data, the air quality of the working area is adjusted by controlling the flow rate of the intelligent fresh air terminal, the flow rate of the fresh air valve and the air processing power of the digital fresh air unit; According to the comparison between the real-time temperature data and the preset temperature data, the temperature of the working area is adjusted by controlling the flow rate of the intelligent air supply terminal and the heat and moisture processing power of the digital air conditioning unit; According to the preset circulating return air volume requirement, the circulating return air volume is adjusted by controlling the flow volume of the return air valve.

[0016] Other features and advantages of the present invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention will be further described below with reference to the accompanying drawings and embodiments; Figure 1 The VAV air conditioning system provided by the present invention, the structure of the embodiment 1 is shown as follows: Figure 1 ; Figure 2 The VAV air conditioning system provided by the present invention, the structure of the second embodiment is shown as follows: Figure 1 ; Figure 3 is a flow chart of the operating method provided by the present invention; Figure Number: Digital fresh air unit 1; digital air conditioning unit 2; digital air supply unit 3; intelligent air supply terminal 4; intelligent fresh air terminal 5; fresh air unit control system 6; air supply unit control system 7; air conditioning unit control system 8; intelligent terminal control system 9; air inlet valve 10; return air valve 11; fresh air valve 12. DETAILED DESCRIPTION

[0018] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0019] In the description of the present invention, it should be understood that descriptions involving orientation, such as the orientation or positional relationship indicated by up, down, etc., are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0020] In the description of the present invention, "a plurality" refers to more than two. The use of "first" or "second" is solely for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of the indicated technical features, or implicitly indicating the order of the indicated technical features.

[0021] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, and connecting should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0022] The technical solutions of the present invention will be described clearly and completely below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of the present invention, not all embodiments.

[0023] like Figure 1 and Figure 2 As shown, a VAV air-conditioning system based on temperature and humidity separate control technology of the present invention includes: an intelligent fresh air terminal 5, an intelligent air supply terminal 4, a digital fresh air unit 1, and a digital air-conditioning unit 2.

[0024] Among them, there is at least one digital fresh air unit 1. In actual application, the number of digital fresh air units 1 is set according to the demand for fresh air volume. The air outlet side of the digital fresh air unit 1 is connected to the fresh air main pipe, and the fresh air main pipe is connected to multiple intelligent fresh air terminals 5 through fresh air branch pipes. The intelligent fresh air terminal 5 is arranged on the fresh air branch pipe in the working area and is responsible for adjusting the fresh air volume.

[0025] The digital air-conditioning unit 2 is provided with at least one, and the air inlet side of the digital air-conditioning unit 2 is provided with a return air valve 11 and a fresh air valve 12. The fresh air valve 12 is connected to the fresh air main pipe, and the return air valve 11 is connected to the return air duct, and the return air duct is connected to the working area. The air outlet side of the digital air-conditioning unit 2 is connected to multiple intelligent air supply terminals 4 through the supply air duct. The intelligent air supply terminal 4 is arranged on the air supply branch pipe of the working area, and is responsible for delivering the air from the digital air-conditioning unit 2 to each working area as needed.

[0026] When in use, the return air volume is adjusted through the return air valve 11, and the fresh air volume entering the digital air conditioning unit 2 is adjusted through the fresh air valve 12, so as to adjust the circulating air.

[0027] The present invention divides the traditional VAV system in which fresh air and return air are jointly processed by one device into two independent systems, that is, the fresh air is processed by the digital fresh air unit 1 and the circulating air is processed by the digital air-conditioning unit 2. One digital fresh air unit 1 corresponds to one digital air-conditioning unit 2 or one digital fresh air unit 1 corresponds to multiple digital air-conditioning units 2. When in use, the digital fresh air unit 1 centrally collects and processes the fresh air, and then transports it to each floor or partition by the fresh air main pipe. Part of the fresh air is transported by each intelligent fresh air terminal 5 to the working area requiring humidity control and air quality control, and the other part of the fresh air enters the digital air-conditioning unit 2 and the return air is processed by the digital air-conditioning unit 2 and then transported to the working area of each open space through the intelligent air supply terminal 4. The intelligent fresh air terminal 5 is arranged on the fresh air branch pipe of the working area, responsible for adjusting the fresh air volume; the intelligent air supply terminal 4 is arranged on the air supply pipe of the working area, responsible for delivering the air from the digital air-conditioning unit 2 to each working area as needed.

[0028] The digital fresh air unit of the present invention only bears the resistance of the fresh air main pipe, completely changing the practice of selecting fan pressure based on the most unfavorable resistance of a particular branch pipe. Due to the reduced wind pressure, air leakage in the air duct is significantly reduced, saving energy consumption in fresh air transmission and distribution. Furthermore, all the fresh air required by a building can be provided by one or more digital fresh air units based on the building's structural characteristics, greatly simplifying the practice of distributing fresh air from decentralized fresh air machine rooms and units, and facilitating construction and maintenance.

[0029] The digital fresh air unit 1 of the present invention includes a fresh air fan for adjusting the supply of fresh air, a fresh air treatment module for performing air purification on the fresh air, and a fresh air heat and humidity treatment module for performing heat and humidity treatment on the fresh air.

[0030] Among them, the fresh air fan adopts a digital EC fan or a variable frequency fan, which can automatically adjust the supply of fresh air according to the user's demand for fresh air volume and the change of resistance of the fresh air supply main pipe, which can greatly save the cold (heat) consumption of processing fresh air and achieve significant energy saving.

[0031] The digital fresh air unit 1 of the present invention has the main goal of ensuring the quality of fresh air (air cleanliness, deodorization, addition of negative ions, etc.), and can also have the functions of fresh air heat and humidity treatment (cooling and dehumidification, heating and humidification, heat recovery, etc.). Its cold and heat source can be a centralized cold and heat source, or an independent direct expansion cold and heat source, or a combination of a centralized cold and heat source + an independent direct expansion cold and heat source.

[0032] The digital fresh air unit 1 undertakes the dehumidification task of the corresponding area, processes the outdoor fresh air to have a certain humidity difference with the indoor air, and controls the humidity and air quality of the working area by adjusting the air volume of the intelligent fresh air terminal 5 or the fresh air valve 12.

[0033] The digital air conditioning unit 2 of the present invention includes an air conditioning fan for adjusting the supply amount of air supply, an air conditioning air processing module for performing air purification treatment on the circulating air, and an air conditioning heat and moisture treatment module for performing heat and moisture treatment on the circulating air.

[0034] The digital air-conditioning unit 2 takes ensuring the quality of circulating air (air cleanliness, deodorization, adding negative ions, etc.) as its main goal, and can also have the function of heat and moisture treatment (cooling, heating, etc.). Its cold and heat source can be a centralized cold and heat source, or an independent direct expansion cold and heat source, or a combination of a centralized cold and heat source + an independent direct expansion cold and heat source.

[0035] The air conditioning fan adopts digital EC fan or variable frequency fan, which can automatically adjust the supply of air according to the user's demand for circulating air volume and the change of resistance of the air supply main pipe, which can greatly save the cold (heat) consumption of return air processing and achieve significant energy saving.

[0036] Further, if Figure 1 As shown, it also includes a digital air supply unit 3, and the inlet of the digital air supply unit 3 is provided with an air inlet valve 10. The digital air supply unit 3 is connected between the fresh air main pipe and the multiple intelligent fresh air terminals 5. The digital air supply unit 3 includes an air supply fan for adjusting the air supply volume. The digital air supply unit 3 is mainly responsible for the secondary distribution of fresh air, and delivers the fresh air from the digital fresh air unit 1 to the air inlet of each intelligent fresh air terminal 5 as needed, so as to be delivered to each work area.

[0037] The air supply fan uses an EC fan, which only bears the resistance of the air supply branch pipe and adjusts the total amount of fresh air according to the change of branch pipe resistance. The adjustment range is 0% to 100%.

[0038] In some embodiments, the digital air supply unit 3 further includes an air supply heat and humidity treatment module for performing heat and humidity treatment on the supply air. It is understandable that a heat exchanger can be provided as needed to perform heat and humidity treatment on the fresh air.

[0039] In some other embodiments, such as Figure 2 As shown, no digital air supply unit 3 is provided, and the humidity and air quality of the working area are controlled by adjusting the air volume of the intelligent fresh air terminal 5 or the fresh air valve 12.

[0040] The intelligent fresh air terminal 5 and the intelligent air supply terminal 4 are divided into two categories according to different principles: non-powered type and powered type.

[0041] The unpowered intelligent fresh air terminal 5 and the intelligent air supply terminal 4 respectively include a shell, a wind speed sensor, and an air volume adjustment mechanism.

[0042] The powered intelligent fresh air terminal 5 and the intelligent air supply terminal 4 respectively include a shell, a wind speed sensor, a terminal fan, and an electric closed valve. The terminal fan adopts an EC fan.

[0043] The intelligent fresh air terminal 5 can deliver the processed fresh air to each work area as needed based on humidity or air quality as the control target, or based on humidity and air quality as the control target.

[0044] The intelligent air supply terminal 4 can deliver the processed circulating air to each work area as needed based on the temperature as the control target.

[0045] The small space working areas corresponding to the digital air-conditioning unit 2 are equipped with intelligent fresh air terminals 5 and intelligent air supply terminals 4. The large space working areas can be equipped with only intelligent air supply terminals 4 or both intelligent fresh air terminals 5 and intelligent air supply terminals 4 according to actual conditions.

[0046] The present invention also includes an intelligent control system, which includes a fresh air unit control system 6, a supply air unit control system 7, an air conditioning unit control system 8 and an intelligent terminal control system 9, which can respectively realize the control of the digital fresh air unit 1, the digital supply air unit 3, the digital air conditioning unit 2 and the intelligent terminal, and can be incorporated into the BA system to accept centralized management by the central monitoring station.

[0047] Among them, the fresh air unit control system 6 includes a fresh air unit intelligent control cabinet, a first supply air pressure sensor, a first air inlet temperature and humidity sensor, a first supply air temperature and humidity sensor, and an air quality sensor connected to the fresh air unit intelligent control cabinet at the same time. The fresh air unit intelligent control cabinet is respectively connected to the fresh air fan, the fresh air air treatment module, and the fresh air heat and humidity treatment module. The fresh air heat and humidity treatment module is provided with an electric regulating valve of the water system or a communication component of the built-in cold and heat source system. According to the change of the air duct pressure, the total amount of fresh air can be automatically adjusted through the fresh air fan. According to the change of the supply air temperature and humidity, the opening of the electric valve can be automatically adjusted or the input ratio of the built-in cold and heat source system can be adjusted to realize the control of the supply air moisture content. The real-time statistics of the fresh air volume can be automatically performed. The controller has a communication interface and can receive BA instructions to realize remote start and stop of the unit.

[0048] The air-conditioning unit control system 8 includes an air-conditioning unit intelligent control cabinet, a second air supply pressure sensor, a second air inlet temperature sensor, and a second air supply temperature sensor connected to the air-conditioning unit intelligent control cabinet. The air-conditioning unit intelligent control cabinet is connected to the air-conditioning fan and the air-conditioning heat and humidity treatment module respectively. The air-conditioning heat and humidity treatment module is also provided with a water system electric regulating valve or a communication component of a built-in cold and heat source system. It can automatically adjust the total air supply volume through the air-conditioning fan according to the change of the air duct pressure; automatically adjust the opening of the electric valve or adjust the input ratio of the built-in cold and heat source system according to the change of the supply air temperature to realize the supply air temperature control, and can automatically perform real-time statistics of the supply air volume; the controller has a communication interface and can receive BA instructions to realize remote start and stop of the unit.

[0049] The air supply unit control system 7 includes an air supply unit controller and an air duct pressure sensor connected to the air supply unit controller. The air supply unit controller is connected to the air supply fan and can automatically adjust the air supply volume according to changes in the air duct pressure.

[0050] The intelligent fresh air terminal 5 and the intelligent air supply terminal 4 respectively include a wind speed sensor and an air volume adjustment mechanism.

[0051] The intelligent terminal control system 9 includes a terminal controller and a sensor group connected to the terminal controller. The sensor group includes one or more VOC sensors, CO2 sensors, temperature and humidity sensors, PM2.5 sensors, and pressure difference sensors. It can automatically adjust the fresh air volume of the fresh air terminal according to changes in indoor VOC, CO2 concentration and humidity, and can automatically adjust the air supply volume of the air supply terminal according to changes in indoor temperature.

[0052] like Figure 1 As shown, the digital fresh air unit 1, the digital air supply unit 3, and the intelligent fresh air terminal 5 adopt a series mode when they are put into operation at the same time. The opening / closing of the digital fresh air unit 1 and the digital air supply unit 3 is controlled by the signal of the air supply pressure sensor, and the opening / closing of the intelligent fresh air terminal 5 is controlled by the terminal controller with the signal of the sensor.

[0053] The digital air-conditioning unit 2 and the intelligent air supply terminal 4 adopt a series mode when they are put into operation at the same time. The opening / closing of the digital air-conditioning unit 2 is controlled by the signal of the air supply pressure sensor, and the opening / closing of the intelligent air supply terminal 4 is controlled by the terminal controller with the signal of the sensor.

[0054] like Figure 2 yes Figure 1 A simplified version of the embodiment, that is, a solution in which one digital fresh air unit 1 corresponds to one digital air conditioning unit 2, and Figure 1 In the embodiment, a digital fresh air unit 1 corresponds to two or more digital air conditioning units 2, and a digital air supply unit 3 is also provided to undertake the secondary distribution of fresh air.

[0055] The small space working areas corresponding to the digital air-conditioning unit 2 are equipped with intelligent fresh air terminals 5 and intelligent air supply terminals 4. The large space working areas can be equipped with only intelligent air supply terminals 4 or both intelligent fresh air terminals 5 and intelligent air supply terminals 4 according to actual conditions.

[0056] This VAV air-conditioning system effectively solves the problem of comprehensive control of temperature, humidity and air quality of VAV air-conditioning system. When a combination of centralized cold and heat source + independent direct expansion cold and heat source is adopted, the centralized cold and heat source can use low-grade energy, which can improve the energy efficiency of the refrigeration host or heat pump, and reduce the annual operating energy consumption of the air-conditioning system by 20% to 25%, and achieve the purpose of comprehensive control of temperature, humidity and air quality of VAV air-conditioning system.

[0057] like Figure 3 As shown, the present invention also provides an operating method, which is applicable to a VAV air conditioning system. The operating method comprises the following steps: Step S100: Acquire real-time humidity data, real-time air quality data, and real-time temperature data of the working area; Step S200: Based on the comparison between the real-time humidity data and the preset humidity data, the humidity of the working area is adjusted by controlling the flow rate of the intelligent fresh air terminal 5, the flow rate of the fresh air valve 12, and the heat and moisture processing power of the digital fresh air unit 1; Step S300: Based on the comparison between the real-time air quality data and the preset air quality data, the air quality of the working area is adjusted by controlling the flow rate of the intelligent fresh air terminal 5, the flow rate of the fresh air valve 12, and the air processing power of the digital fresh air unit 1; Step S400: Based on the comparison between the real-time temperature data and the preset temperature data, the temperature of the working area is adjusted by controlling the flow rate of the intelligent air supply terminal 4 and the heat and moisture processing power of the digital air conditioning unit 2; Step S500: According to the preset circulating return air volume requirement, the circulating return air volume is adjusted by controlling the flow rate of the return air valve 11.

[0058] Throughout this specification, references to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "example," "specific example," or "some examples" indicate that a particular feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, illustrative uses of these terms do not necessarily refer to the same embodiment or example. Furthermore, the described specific features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments or examples.

[0059] The embodiments of the present invention are described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Various changes can be made within the knowledge of ordinary technicians in the relevant technical field without departing from the scope of the present invention.

Claims

1. A VAV air conditioning system based on temperature and humidity separate control technology, characterized in that: include: Intelligent fresh air terminal (5), with multiple; Intelligent air supply terminal (4), provided with a plurality of; A digital fresh air unit (1) is provided with at least one, wherein the air outlet side of the digital fresh air unit (1) is connected to a fresh air main pipe, and the fresh air main pipe is connected to a plurality of the intelligent fresh air terminals (5) via fresh air branch pipes; A digital air conditioning unit (2) is provided with at least one, wherein the air inlet side of the digital air conditioning unit (2) is provided with a return air valve (11) and a fresh air valve (12), the fresh air valve (12) is connected to the fresh air main pipe, the return air valve (11) is connected to the return air duct, and the air outlet side of the digital air conditioning unit (2) is connected to the plurality of the intelligent air supply terminals (4) via the air supply duct.

2. The VAV air conditioning system according to claim 1, characterized in that: The digital fresh air unit (1) comprises a fresh air fan for adjusting the supply of fresh air, a fresh air treatment module for performing air purification treatment on the fresh air, and a fresh air heat and humidity treatment module for performing heat and humidity treatment on the fresh air.

3. The VAV air conditioning system according to claim 2, characterized in that: The digital air conditioning unit (2) comprises an air conditioning fan for adjusting the supply amount of air supply, an air conditioning air processing module for performing air purification treatment on the circulating air, and an air conditioning heat and moisture treatment module for performing heat and moisture treatment on the circulating air.

4. The VAV air conditioning system according to claim 3, characterized in that: It also includes a digital air supply unit (3), which is connected between the fresh air main pipe and the plurality of intelligent fresh air terminals (5), and includes an air supply fan for adjusting the air supply volume.

5. The VAV air conditioning system according to claim 4, characterized in that: The digital air supply unit (3) further comprises an air supply heat and moisture treatment module for performing heat and moisture treatment on the supply air.

6. The VAV air conditioning system according to claim 4, characterized in that: It also includes an intelligent control system, which includes a fresh air unit control system (6), a supply air unit control system (7), and an air conditioning unit control system (8); The fresh air unit control system (6) includes a fresh air unit intelligent control cabinet, a first air supply pressure sensor, a first air inlet temperature and humidity sensor, a first air supply temperature and humidity sensor, and an air quality sensor connected to the fresh air unit intelligent control cabinet, and the fresh air unit intelligent control cabinet is connected to the fresh air fan, the fresh air air processing module, and the fresh air heat and humidity processing module respectively; The air conditioning unit control system (8) includes an air conditioning unit intelligent control cabinet, a second air supply pressure sensor, a second air inlet temperature sensor, and a second air supply temperature sensor connected to the air conditioning unit intelligent control cabinet, and the air conditioning unit intelligent control cabinet is connected to the air conditioning fan and the air conditioning heat and humidity processing module respectively; The air supply unit control system (7) comprises an air supply unit controller and an air duct pressure sensor connected to the air supply unit controller, and the air supply unit controller is connected to the air supply fan.

7. The VAV air conditioning system according to claim 1, characterized in that: The intelligent fresh air terminal (5) and the intelligent air supply terminal (4) respectively include a wind speed sensor and an air volume adjustment mechanism.

8. The VAV air conditioning system according to claim 1, characterized in that: The intelligent fresh air terminal (5) and the intelligent air supply terminal (4) respectively include a wind speed sensor and a terminal fan.

9. The VAV air conditioning system according to any one of claims 7 or 8, characterized in that: It also includes an intelligent control system, the intelligent control system includes an intelligent terminal control system (9), and the intelligent terminal control system (9) includes a terminal controller and a sensor group connected to the terminal controller; The sensor group includes one or more of a VOC sensor, a CO2 sensor, a temperature and humidity sensor, a PM2.5 sensor, and a pressure difference sensor.

10. An operating method, characterized in that: It is applicable to the VAV air conditioning system according to any one of claims 1 to 9, and the operating method includes: Obtain real-time humidity data, real-time air quality data, and real-time temperature data in the working area; According to the comparison between the real-time humidity data and the preset humidity data, the humidity of the working area is adjusted by controlling the flow rate of the intelligent fresh air terminal (5), the flow rate of the fresh air valve (12) and the heat and moisture processing power of the digital fresh air unit (1); According to the comparison between the real-time air quality data and the preset air quality data, the air quality of the working area is adjusted by controlling the flow rate of the intelligent fresh air terminal (5), the flow rate of the fresh air valve (12) and the air processing power of the digital fresh air unit (1); According to the comparison between the real-time temperature data and the preset temperature data, the temperature of the working area is adjusted by controlling the flow rate of the intelligent air supply terminal (4) and the heat and moisture processing power of the digital air conditioning unit (2); According to the preset circulating return air volume requirement, the circulating return air volume is adjusted by controlling the flow volume of the return air valve (11).

Images