Fresh air conditioning device, control method thereof and air conditioning system

Abstract

The present invention discloses a fresh air conditioning device, its control method and air conditioning system. The fresh air conditioning device includes a shell and a core body. The internal space of the shell is divided into an upper air duct, a lower air duct and a middle space. A rhombus-shaped first core body and a second core body are arranged side by side in the middle space. An adjacent rhombus side of the two core bodies is connected to a partition and separated from each other. The upper and lower rhombus sides of the two core bodies are respectively connected to the bottom plate of the upper air duct and the top plate of the lower air duct. The series-parallel air ducts of the fresh air and return air of the first core body and the second core body are formed by the shell, the partition, the upper air duct, the lower air duct and the control air valve. The present invention can accurately adjust the air volume and static pressure of the fresh air unit according to demand, while reducing the overall size of the unit and the wind resistance of the core body, thereby reducing energy consumption.

Description

Technical Field

[0001] The present invention relates to the technical field of air conditioning, and in particular to a fresh air conditioning device with heat exchange cores connected in series or parallel, a control method thereof, and an air conditioning system. Background Art

[0002] Central air conditioning controls indoor air temperature and humidity, significantly improving worker comfort. To ensure air quality, a certain percentage of fresh air must be introduced, leading to a surge in demand for fresh air from central air conditioning. Conventional large, fixed-frequency fresh air units suffer from issues with adjustable air volume and static pressure. When the static pressure drop within the unit is excessive, the overall power consumption increases. Furthermore, large fresh air units are too large, resulting in insufficient space for hoisting and installation. Summary of the Invention

[0003] The present invention proposes a fresh air conditioning device with heat exchange cores that can be connected in series or parallel, its control method and air conditioning system, to solve the technical problems of existing fresh air units such as the inability to adjust the air volume and static pressure, excessive internal static pressure drop, high power consumption of the whole unit, and large installation size.

[0004] The present invention proposes a fresh air conditioning device, including a shell and a core body, the internal space of the shell is divided into an upper air duct, a lower air duct and a middle space, a rhombus-shaped first core body and a second core body are arranged side by side in the middle space, an adjacent rhombus side of the two core bodies is connected to a partition and separated from each other, the upper and lower rhombus sides of the two core bodies are respectively connected to the bottom plate of the upper air duct and the top plate of the lower air duct, and the series-parallel air ducts of the fresh air and return air of the first core body and the second core body are formed by the partition, the upper air duct, the lower air duct and the control air valve.

[0005] The control air valve includes: a first air valve connecting the return air of the upper air duct and the return air inlet of the first core; a second air valve connecting the fresh air of the upper air duct and the fresh air inlet of the second core; a third air valve connecting the return air outlet of the second core to the return air inlet of the first core; a fourth air valve connecting the fresh air outlet of the first core to the fresh air inlet of the second core; a fifth air valve connecting the return air outlet of the second core to the return air of the lower air duct and a sixth air valve connecting the fresh air outlet of the first core to the fresh air of the lower air duct.

[0006] Preferably, the upper air duct and the lower air duct are provided with bending plates forming inlet and outlet air ducts for fresh air and return air, and the bending plates include a middle flat plate, a first flat plate and a second flat plate which are bent vertically in opposite directions from both ends of the middle flat plate.

[0007] Preferably, the first air valve and the second air valve are arranged on the bottom plate of the upper air duct and are located on both sides of the partition.

[0008] Preferably, the third air valve is arranged at the upper part of the partition, and the fourth air valve is arranged at the lower part of the partition.

[0009] Preferably, the fifth air valve and the sixth air valve are arranged on the top plate of the lower air duct and are located on both sides of the partition.

[0010] In the parallel connection mode of the first core and the second core, the first air valve, the second air valve, the fifth air valve and the second air valve are opened, and the third air valve and the fourth air valve are closed; in the series connection mode of the first core and the second core, the first air valve, the second air valve, the fifth air valve and the sixth air valve are closed, and the third air valve and the fourth air valve are opened.

[0011] Preferably, in both the series-parallel connection mode of the first core and the second core, the air volume and static pressure can be adjusted by adjusting the opening size of the control air valve.

[0012] The fresh air conditioning device proposed in the present invention also includes a plurality of infrared detectors arranged in different areas of the room for detecting the number and position of human bodies.

[0013] The fresh air conditioning device proposed in the present invention also includes a plurality of CO2 concentration detectors arranged in different areas of the room.

[0014] The two ends of the fresh air regulating device are respectively connected to the inlet and outlet pipes of the fresh air and the return air. Fans are provided in the inlet and outlet pipes of the fresh air and the return air.

[0015] The present invention also proposes a control method for the above-mentioned fresh air conditioning device. When the average value of the indoor CO2 concentration is within the comfort concentration threshold range and the initial demand for fresh air by the indoor personnel is less than or equal to the fresh air volume threshold, the first core and the second core are controlled to enter the series operation mode; when the initial demand for fresh air by the indoor personnel is greater than the fresh air volume threshold, the first core and the second core are controlled to enter the parallel operation mode.

[0016] When the average indoor CO2 concentration is not within the comfort concentration threshold range, open the first air valve, the second air valve, the fifth air valve and the sixth air valve, start the fan and run it for m minutes, then return to re-detect the number of people in the room and the CO2 concentration.

[0017] When the fresh air conditioning device enters the series operation mode, perform the following steps:

[0018] Open the third and fourth air valves halfway, record the increase in opening amount Si, start the fan and run it for m minutes, obtain the CO2 concentration, and calculate the average CO2 concentration ηii;

[0019] Determine whether the absolute value of the difference between the current average value of CO2 concentration and the average value of the previous CO2 concentration is less than or equal to the difference △. If so, maintain operation for N minutes and then re-determine the operation mode; if not, further determine the change in the two previous and subsequent real-time CO2 concentration values;

[0020] When the current average CO2 concentration ηii is greater than or equal to the previous average CO2 concentration ηi, increase the opening of the third and fourth air valves by half of the unopened portion, record the increased opening amount Sa, start the fan and run for m minutes, then re-determine the operating mode;

[0021] When the current average value ηii of CO2 concentration is less than or equal to the average value ηi of the previous CO2 concentration, reduce the third and fourth air valves by half of the last opening part, record the increase in opening amount Sa, start the fan and run for m minutes, then re-determine the operating mode.

[0022] When the fresh air conditioning device enters and operates in mode, perform the following steps:

[0023] Open the first, second, fifth, and half of the sixth air valves, record the increase in opening amount Si, start the fan and run it for m minutes, then obtain the CO2 concentration and take the average CO2 concentration ηii;

[0024] Determine whether the absolute value of the difference between the current average value of CO2 concentration and the average value of the previous CO2 concentration is less than or equal to the difference △. If so, maintain operation for N minutes and re-determine the operation mode; if not, further determine the change in the two real-time CO2 concentration values ​​before and after;

[0025] When the current average CO2 concentration is greater than the previous average CO2 concentration, increase the opening of the first, second, fifth, and sixth air valves by half of their unopened positions, record the increased opening amount Sa, start the fans and run them for m minutes before re-determining the operating mode.

[0026] When the current average value of CO2 concentration is less than or equal to the average value of the previous CO2 concentration, reduce the first, second, fifth and sixth air valves by half of the last opening amount, record the increase in opening amount Sb, start the fan and run for m minutes before re-determining the operating mode.

[0027] The present invention also provides an air conditioning system, which includes the above-mentioned fresh air conditioning device and adopts the above-mentioned fresh air conditioning device control method to control the operation of the fresh air unit.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] 1. The present invention adopts a bent plate air duct structure design in the upper and lower air ducts, forming a series-parallel operation mode in the heat exchange core of the fresh air unit. The air flow is separated in the core and the branches are merged and controlled in the upper and lower air ducts, so that the air volume and static pressure can be adjusted in a step-by-step manner according to demand.

[0030] 2. The present invention adopts a series-parallel structural arrangement of the heat exchange core, which greatly reduces the pressure loss inside the machine, reduces the size of the unit, and provides ample space for unit hoisting.

[0031] 3. The present invention adopts a two-stage air duct control scheme of the core and the upper and lower air ducts, which realizes the demand for precise control of fresh air supply and reduces the power consumption of the whole machine. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments, wherein:

[0033] Figure 1 It is a three-dimensional schematic diagram of the fresh air conditioning device proposed by the present invention;

[0034] Figure 2 yes Figure 1 A cross-sectional schematic diagram of the fresh air conditioning device shown;

[0035] Figure 3 This is a schematic diagram of the internal structure of the fresh air conditioning device;

[0036] Figure 4 This is a schematic diagram of the fresh air flow direction in the parallel operation mode of two heat exchange cores;

[0037] Figure 5 This is a schematic diagram of the return air flow direction in the parallel operation mode of two heat exchange cores;

[0038] Figure 6 This is a schematic diagram of the fresh air flow direction in the two heat exchange cores series operation mode;

[0039] Figure 7 This is a schematic diagram of the return air flow direction in the series operation mode of two heat exchange cores;

[0040] Figure 8 It is a control flow chart of the fresh air conditioning device of the present invention. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the following specific embodiments are only used to explain the present invention and do not constitute a limitation of the present invention.

[0042] The present invention adopts a side-by-side design of the heat exchange core combined with the structural design of the upper and lower air ducts, and cooperates with the control air valve to enable the heat exchange core air ducts to be freely switched into series and parallel modes, thereby realizing step-by-step adjustment of the heat exchange core air volume and static pressure, and achieving precise adjustment of the fresh air supply.

[0043] like Figures 1 to 3As shown, the fresh air conditioning device proposed in the present invention includes a shell and a core, and the internal space of the shell is divided into an upper air duct 1, a lower air duct 2 and a middle space 3. A rhombus-shaped first core 4 and a second core 5 are arranged side by side in the middle space. From the cross-section, the two vertices of the two cores are in the vertical direction, and the other two vertices are in the horizontal direction. A horizontal rhombus edge adjacent to the two cores is connected to a vertical partition 6, which separates the middle space into left and right sides. A rhombus edge of the two cores that is far away from each other in the horizontal direction is connected to the shell, and the upper and lower rhombus edges of the two cores in the vertical direction are respectively connected to the bottom plate of the upper air duct 1 and the top plate of the lower air duct 2. The series-parallel air ducts for the fresh air and return air of the first core and the second core are formed by the shell, the partition, the upper air duct, the lower air duct and the control air valve.

[0044] In the fresh air conditioning device proposed in the present invention, the entire air duct structure is divided into three layers of air ducts: upper, middle and lower layers, namely the upper air duct composed of the upper bent plate, the middle serial-parallel core air duct and the lower air duct composed of the lower bent plate.

[0045] like Figures 4 to 7 As shown, a bending plate 13 is provided in each of the upper air duct 1 and the lower air duct 2. The bending plate includes a middle flat plate and a first flat plate and a second flat plate bent vertically in opposite directions from both ends of the middle flat plate. The bending plate and the shell form fresh air and return air channels in the upper air duct and the lower air duct.

[0046] The control air valves include: a first air valve 7 connecting the return air from the upper duct with the return air inlet of the first core; a second air valve 8 connecting the fresh air from the upper duct with the fresh air inlet of the second core. The first and second air valves 7 and 8 are arranged on the bottom plate of the upper duct 1 and on either side of the partition 6; a third air valve 9 connecting the return air outlet of the second core to the return air inlet of the first core; and a fourth air valve 10 connecting the fresh air outlet of the first core to the fresh air inlet of the second core. The third air valve 9 is arranged on the upper part of the partition 6, and the fourth air valve 10 is arranged on the lower part of the partition 6; a fifth air valve 11 connecting the return air outlet of the second core to the return air of the lower duct; and a sixth air valve 12 connecting the fresh air outlet of the first core to the fresh air of the lower duct. The fifth and sixth air valves 11 and 12 are arranged on the top plate of the lower duct 2 and on either side of the partition 6. By controlling these air valves, the first and second cores can achieve series and parallel duct switching while performing full heat exchange.

[0047] The two ends of the fresh air conditioning device are connected to the inlet and outlet pipes of fresh air and return air respectively. Figure 1 In the embodiment shown, the fresh air inlet A1 and the return air outlet B2 are arranged on the left, and the fresh air outlet A2 and the return air inlet B1 are arranged on the right, and fans are provided in both the inlet and outlet ducts.

[0048] exist Figure 4 and Figure 5In the parallel mode of the first core and the second core shown, the first air valve 7, the second air valve 8, the fifth air valve 11 and the second air valve 12 are open, and the third air valve 9 and the fourth air valve 10 are closed. The first air valve 7 is the return air inlet of the first core 4. Part of the return air flows directly to the return air inlet of the second core, and part of the return air enters the return air inlet of the first core through the upper air duct and the first air valve 7. The second air valve 8 is the fresh air inlet of the second core 5. Part of the fresh air flows directly to the fresh air inlet of the first core, and part of the fresh air enters the fresh air inlet of the second core through the upper air duct and the second air valve. The fifth air valve 11 is the return air outlet of the second core 5. The return air flowing out of the second core enters the lower air duct through the fifth air valve, and is then discharged into the return air duct together with the return air from the return air outlet of the first core. Figure 5 The sixth damper 12 is the fresh air outlet for the first core 4. Fresh air discharged from the first core enters the fresh air duct below, then, along with fresh air discharged from the second core, is delivered through the fresh air outlet into the fresh air duct, direction A2, and then into the room. In parallel mode, the third damper 9 and the fourth damper 10 are closed.

[0049] exist Figure 6 and Figure 7 In the illustrated first and second cores connected in series mode, the first, second, fifth, and sixth air valves 7, 8, 11, and 12 are closed. The third and fourth air valves 9, 10 are open. The third air valve 9 connects the return air outlet of the second core to the return air inlet of the first core, and the fourth air valve 10 connects the fresh air outlet of the first core 4 to the fresh air inlet of the second core 5.

[0050] In both the series-parallel connection mode of the first core and the second core, the air volume and static pressure can be adjusted by adjusting the opening size of the control air valve.

[0051] The fresh air conditioning device proposed in the present invention also includes multiple infrared detectors and multiple CO2 concentration detectors arranged in different areas indoors for detecting the number and position of human bodies.

[0052] In the control method of the fresh air conditioning device proposed in the present invention, when the average value of the indoor CO2 concentration is within the comfort concentration threshold range and the initial demand for fresh air by the indoor personnel is less than or equal to the fresh air volume threshold, the first core and the second core are controlled to enter the series operation mode; when the initial demand for fresh air by the indoor personnel is greater than the fresh air volume threshold, the first core and the second core are controlled to enter the parallel operation mode.

[0053] Figure 8 The two-stage air duct control flow chart of the present invention includes the following steps:

[0054] Step 1: When the unit starts, first start the indoor infrared detector and CO2 concentration detector:

[0055] ① Determine the number of people n in the space and the fresh air demand Q, Q = nB; where B is the fresh air demand per person. The industry has per capita fresh air volume parameters for different occasions.

[0056] ② Obtain the CO2 concentration at various locations in the room and take the average value ηi;

[0057] Step 2: Determine whether the current average CO2 value ηi is within the comfortable concentration threshold range [ηa, ηb], that is, ηa≤ηi≤ηb;

[0058] ① If not, open the first air valve 7, the second air valve 8, the fifth air valve 11 and the sixth air valve 12, start the fan and run for m minutes, then return to step 1;

[0059] ② If yes, further determine the difference between the calculated current fresh air demand Q and the set fresh air volume threshold A;

[0060] Step 3: When the fresh air demand Q is less than or equal to the set fresh air volume threshold A, Q≤A, and the core body enters the series operation mode; when the fresh air demand Q is greater than the set fresh air volume threshold A, Q>A, and the core body enters the parallel operation mode.

[0061] In cascade operation mode, perform the following steps:

[0062] Step 4: Open the third air valve 9 and half of the fourth air valve 10, record the increase in opening amount Si, start the fan and run it for m minutes, obtain the CO2 concentration, and calculate the average CO2 concentration ηii;

[0063] Step 5: Determine whether the absolute value of the difference between the current average CO2 concentration and the previous average CO2 concentration is less than or equal to the difference △, |ηii-ηi|≤△. If so, continue running for N minutes and then return to step 1; if not, further determine the change in the two previous average CO2 concentration values;

[0064] Step 6: When the current average CO2 concentration ηii is greater than the previous average CO2 concentration ηi, ηii>ηi, then increase the opening of the third air valve 9 and the fourth air valve 10 by half of the unopened portion, record the increased opening amount Sa, start the fan and run for m minutes, then return to step 1;

[0065] When the current average value ηii of the CO2 concentration is less than or equal to the average value ηi of the previous CO2 concentration, ηii≤ηi, reduce the last opening amount of the third air valve 9 and the fourth air valve 10 by half, record the increase in the opening amount Sa, start the fan and run it for m minutes, then return to step 1.

[0066] In parallel operation mode, perform the following steps:

[0067] Step 4′: Open the first air valve 7, the second air valve 8, the fifth air valve 11, and half of the sixth air valve 12, record the increase in opening amount Si, start the fan and run it for m minutes, obtain the CO2 concentration, and take the average CO2 concentration ηii;

[0068] Step 5′ determines whether the absolute value of the difference between the current average CO2 concentration and the previous average CO2 concentration is less than or equal to the difference △, |ηii-ηi|≤△. If so, continue running for N minutes and then return to step 1; if not, further determine the change in the two previous average CO2 concentration values;

[0069] Step 6′: When the current average CO2 concentration is greater than the previous average CO2 concentration, ηii>ηi, increase the opening of the first air valve 7, the second air valve 8, the fifth air valve 11, and the sixth air valve 12 by half, record the increase in opening amount Sa, start the fan and run for m minutes, then return to step 1;

[0070] When the current average value of CO2 concentration is less than or equal to the average value of the previous CO2 concentration, ηi i<ηi, reduce the first air valve 7, the second air valve 8, the fifth air valve 11 and the sixth air valve 12 by half of the last opening amount, record the reduced opening amount Sb, start the fan and run for m minutes, then return to step 1.

[0071] The fresh air regulating device and control method proposed in the present invention realizes precise adjustment of the air volume and static pressure of the fresh air unit according to needs through the upper and lower air ducts and the series-parallel core air duct structure, combined with the two-stage air duct control method; at the same time, the wind resistance of the unit core is reduced, thereby reducing energy consumption. The larger the specifications of the whole machine, the more obvious the effect; in addition, the two cores are arranged side by side, which reduces the size of the fresh air unit and facilitates installation.

[0072] The above description is only a specific embodiment of the present invention. It should be pointed out that any modifications, equivalent replacements and changes made within the spirit and framework of the present invention should be included in the scope of protection of the present invention.

Claims

1. A fresh air conditioning device, comprising a shell and a core, characterized in that: The interior space of the shell is divided into an upper air duct, a lower air duct and a middle space. A first core and a second core are arranged side by side in the middle space. An adjacent diamond edge of the two cores is connected to a vertical partition and separated from each other. The upper and lower diamond edges of the two cores are respectively connected to the bottom plate of the upper air duct and the top plate of the lower air duct. The series-parallel air ducts for fresh air and return air of the first core and the second core are formed through the shell, the partition, the upper air duct, the lower air duct and the control air valve. The upper and lower air ducts are provided with bent plates forming inlet and outlet air ducts for fresh air and return air, the bent plates comprising a middle flat plate, a first flat plate and a second flat plate bent perpendicularly in opposite directions from both ends of the middle flat plate; The control air valve includes: a first air valve connecting the return air of the upper air duct and the return air inlet of the first core; a second air valve connecting the fresh air of the upper air duct and the fresh air inlet of the second core; a third air valve connecting the return air outlet of the second core to the return air inlet of the first core; a fourth air valve connecting the fresh air outlet of the first core to the fresh air inlet of the second core; a fifth air valve connecting the return air outlet of the second core to the return air of the lower air duct and a sixth air valve connecting the fresh air outlet of the first core to the fresh air of the lower air duct.

2. The fresh air conditioning device according to claim 1, characterized in that: The first air valve and the second air valve are arranged on the bottom plate of the upper air duct and are located on both sides of the partition.

3. The fresh air conditioning device according to claim 1, characterized in that: The third air valve is arranged on the upper part of the partition plate, and the fourth air valve is arranged on the lower part of the partition plate.

4. The fresh air conditioning device according to claim 1, characterized in that: The fifth air valve and the sixth air valve are arranged on the top plate of the lower air duct and are located on both sides of the partition.

5. The fresh air conditioning device according to claim 1, characterized in that: In the parallel connection mode of the first core and the second core, the first air valve, the second air valve, the fifth air valve and the sixth air valve are opened, and the third air valve and the fourth air valve are closed; in the series connection mode of the first core and the second core, the first air valve, the second air valve, the fifth air valve and the sixth air valve are closed, and the third air valve and the fourth air valve are opened.

6. The fresh air conditioning device according to claim 5, characterized in that: In both the series-parallel connection mode of the first core and the second core, the air volume and static pressure can be adjusted by adjusting the opening size of the control air valve.

7. The fresh air conditioning device according to claim 1, characterized in that: It also includes multiple infrared detectors set up in different areas indoors to detect the number and position of human bodies.

8. The fresh air conditioning device according to claim 1, characterized in that: It also includes multiple CO2 concentration detectors set up in different areas indoors.

9. The fresh air conditioning device according to claim 1, characterized in that: Both ends of the fresh air regulating device are communicated with the inlet and outlet pipes of the fresh air and the return air respectively.

10. The fresh air conditioning device according to claim 9, characterized in that: Fans are provided in the inlet and outlet ducts of the fresh air and the return air.

11. The control method of the fresh air conditioning device according to any one of claims 1 to 10, characterized in that: When the average indoor CO2 concentration is within the comfort concentration threshold range and the initial demand for fresh air by indoor occupants is less than or equal to the set fresh air volume threshold, the first core and the second core are controlled to enter the series operation mode; when the initial demand for fresh air by indoor occupants is greater than the set fresh air volume threshold, the first core and the second core are controlled to enter the parallel operation mode.

12. The control method according to claim 11, wherein: When the average indoor CO2 concentration is not within the comfortable concentration threshold range, open the first air valve, the second air valve, the fifth air valve and the sixth air valve, start the fan and run it for m minutes, then re-test the number of people in the room and the CO2 concentration.

13. The control method according to claim 11, wherein: After entering the cascade operation mode, perform the following steps: Open the third and fourth air valves halfway, record the increase in opening amount Si, start the fan and run it for m minutes, obtain the CO2 concentration, and take the average CO2 concentration ηii; Determine whether the absolute value of the difference between the current average CO2 concentration and the previous average CO2 concentration is less than or equal to the difference △. If so, maintain operation for N minutes and then re-determine the operation mode; if not, further determine the change in the average CO2 concentration between the two times; When the current average CO2 concentration ηii is greater than the previous average CO2 concentration ηi, increase the opening of the third and fourth air valves by half of the unopened portion, record the increased opening amount Sa, start the fan and run for m minutes, then re-determine the operating mode; When the current average value ηii of CO2 concentration is less than or equal to the average value ηi of the previous CO2 concentration, reduce the third and fourth air valves by half of the last opening part, record the increase in opening amount Sa, start the fan and run for m minutes, then re-determine the operating mode.

14. The control method according to claim 11, wherein: Once in and running mode, perform the following steps: Open the first, second, fifth, and half of the sixth air valves, record the increase in opening amount Si, start the fan and run it for m minutes, then obtain the CO2 concentration and take the average CO2 concentration ηii; Determine whether the absolute value of the difference between the current average CO2 concentration and the previous average CO2 concentration is less than or equal to the difference △. If so, maintain operation for N minutes and re-determine the operation mode; if not, further determine the change in the average CO2 concentration between the two times; When the current average CO2 concentration is greater than or equal to the previous average CO2 concentration, increase the opening of the first, second, fifth, and sixth air valves by half of the unopened portion, record the increased opening amount Sa, start the fan and run it for m minutes, then re-determine the operating mode; When the current average value of CO2 concentration is less than or equal to the average value of the previous CO2 concentration, reduce the first, second, fifth and sixth air valves by half of the last opening amount, record the increase in opening amount Sb, start the fan and run for m minutes, then re-determine the operating mode.

15. An air conditioning system, characterized in that: It includes the fresh air conditioning device according to any one of claims 1 to 10.

16. An air conditioning system, characterized in that: It adopts the control method of the fresh air conditioning device described in any one of claims 11-14.

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