Accurate humidity control equipment for improving tobacco leaf curing quality and control method

Abstract

The invention discloses accurate humidity control equipment for improving tobacco leaf curing quality. According to the technical scheme, the curing barn comprises a curing barn body, a heating chamber, an air supplementing opening and an air outlet, an air supplementing shutter is arranged on the air supplementing opening and composed of a plurality of rotatable air supplementing blades, an air outlet shutter is arranged on the air outlet and composed of a plurality of rotatable air outlet blades, and a water-free intelligent dry and wet bulb sensor and an automatic control instrument are arranged in the curing barn. A plurality of air supplementing motors are arranged on the air supplementing port, the number of the air supplementing motors is the same as that of the air supplementing blades, the air supplementing motors are connected with the air supplementing blades in a one-to-one correspondence mode, a plurality of air outlet motors are arranged on the air outlet, the number of the air outlet motors is the same as that of the air outlet blades, and the air outlet motors are connected with the air outlet blades in a one-to-one correspondence mode. According to the system, the actual dry-bulb temperature, wet-bulb temperature and relative humidity data in the curing barn body can be accurately controlled, tobacco leaves are prevented from being damaged by curing, the quality of the tobacco leaves is improved, energy consumption is reduced, and economic benefits are improved.

Description

Technical Field

[0001] The present invention relates to the field of baking equipment, and more specifically to precise moisture control equipment and a control method for improving the baking quality of tobacco leaves. Background Art

[0002] The existing tobacco leaf intensive curing rooms are all built in accordance with the "418" document. The wet-bulb temperature control of the curing process is based on a humidity temperature sensor equipped with water. The control logic is that when the monitored wet-bulb temperature is higher than the target wet-bulb temperature, the cold air inlet door (i.e., air supply door, air supply window) is opened, and the hot and humid air in the curing room is forced to be discharged from the louver (i.e., air outlet door, exhaust window) by supplying fresh air, and the wet-bulb temperature is reduced by replacing the moisture in the air. When the wet-bulb temperature is about to reach the target temperature, the cold air inlet door is closed. The existing air supply window and exhaust window have the following shortcomings: the air supply window uses an electric rotating single-piece louver to control the size of the air supply. When the single-piece louver is rotated, the ventilation area and the rotation angle are extremely nonlinear, and it is difficult to accurately control the air supply volume; the exhaust window uses a free one-way swinging louver. Due to the influence of environmental factors, the free swinging louver cannot be automatically controlled. Under different wind pressures and different frictions, the exhaust is completely uncontrolled. The above-mentioned wet-bulb temperature sensor is insensitive to the relative humidity of the air, which leads to dehumidification lag (wet-bulb temperature is higher than the target wet-bulb temperature) or excessive dehumidification (wet-bulb temperature is lower than the target wet-bulb temperature) during wet-bulb control, causing the wet-bulb temperature in the curing room to always hover around the target value. The wet-bulb temperature control is not accurate, resulting in poor oil content in tobacco leaves due to excessive dehumidification, and even the appearance of "smooth leaves, green leaves", or ash or even steamed leaves due to untimely dehumidification. In this way, the quality of tobacco leaves is not high, and even the phenomenon of bad tobacco leaves occurs, which brings great losses to agricultural production. Summary of the invention

[0003] In view of the deficiencies in the prior art, the object of the present invention is to provide a precise moisture control equipment and control method for improving the quality of tobacco leaf baking to solve the above technical problems.

[0004] To achieve the above-mentioned purpose, the present invention provides the following technical scheme: a precise humidity control equipment for improving the baking quality of tobacco leaves, comprising a baking room body and a heating chamber arranged in the baking room body, the baking room body is provided with an air supply port and an air outlet, the air supply port is provided with an air supply louver, the air supply louver is composed of a plurality of rotatable air supply blades, the air outlet is provided with an air outlet louver, the air outlet louver is composed of a plurality of rotatable air outlet blades, a waterless intelligent dry-bulb and wet-bulb sensor and an automatic control instrument are arranged in the baking room, the air supply port is provided with a plurality of air supply motors, the number of the air supply motors is the same as the number of the air supply blades, the air supply motors are connected to the air supply blades in a one-to-one correspondence, the air outlet is provided with a plurality of air outlet motors, the number of the air outlet motors is the same as the number of the air outlet blades, the air outlet motors are connected to the air outlet blades in a one-to-one correspondence, the automatic control instrument is connected to the waterless intelligent dry-bulb and wet-bulb sensor, the air supply motor and the air outlet motor, and the waterless intelligent dry-bulb and wet-bulb sensor outputs dry-bulb temperature data, wet-bulb temperature data and relative humidity data to the automatic control instrument.

[0005] A control method for precise humidity control equipment,

[0006] There are A air supply motors, and the i-th air supply motor is defined as Di, where i is a natural number between 1 and A. The i-th air supply motor has two on and off states: Di=1 for on; Di=0 for off;

[0007] There are B air outlet motors, and the mth air outlet motor is defined as Em, where m is a natural number between 1 and B. The mth air outlet motor has two on and off states: Em=1 for on; and Em=0 for off.

[0008] According to the set program, the corresponding number of air supply motors and air outlet motors are turned on in different stages.

[0009] As a further improvement of the present invention, the increase and decrease amount of the air supply motor and the air outlet motor are set, and then the number of the air supply motor and the air outlet motor is controlled according to the increase and decrease amount of the air supply motor and the air outlet motor.

[0010] The calculation method of the increase and decrease of the opening amount of the air supply motor and the opening amount of the air outlet motor is as follows:

[0011] Step 1:

[0012] The same set of target dry-bulb and wet-bulb temperatures in the oven corresponds to a relative air humidity range, Ld1~Ld2=);

[0013] Lg1=Lg+0.1

[0014] Ls1=Ls-0.1

[0015] Ld1=(e^(ln611.2+A*Ls1 / (B+Ls1))-P*(Lg1-Ls1)) / e^(ln611.2+A*Lg1 / (B+Lg1))

[0016] Assume: Lg2 = Lg-0.1

[0017] Ls2=Ls+0.1

[0018] Ld2=(e^(ln611.2+A*Ls2 / (B+Ls2))-P*(Lg2-Ls2)) / e^(ln611.2+A*Lg2 / (B+Lg2))

[0019] Where: A is the temperature constant in the range of 30℃-100℃

[0020] B is the absolute temperature corresponding to 30℃

[0021] e is the base of natural logarithm ≈ 2.71828

[0022] P is the pressure interval constant

[0023] Determine the target dry bulb temperature of the oven as Lg and the target wet bulb temperature as Ls; read the actual dry bulb temperature of the oven as Mg, the actual wet bulb temperature as Ms, and the actual relative humidity as Md; where the target dry bulb temperature is Lg, the target wet bulb temperature is Ls, the actual dry bulb temperature is Mg, and the actual wet bulb temperature is Ms, rounded; determine the air supply / exhaust ratio coefficient as K;

[0024] Calculate the difference between the target dry bulb temperature Lg and the actual dry bulb temperature Mg, i.e. Lg-Mg=Xg;

[0025] Calculate the difference between the target wet bulb temperature Ls and the actual wet bulb temperature Ms, that is, Ls-Ms=Xs;

[0026] Calculate the difference between the target relative humidity Ld and the actual relative humidity Md, that is, 100*(Ld-Md)=Xd;

[0027] Calculate the wet bulb temperature difference and the wet bulb temperature difference before time Ns, that is, Xsn-Xs=Δs;

[0028] Calculate the relative humidity difference and the relative humidity difference before time Ns, that is, Xdn-Xd=Δd;

[0029] Calculate the dry bulb temperature difference and the dry bulb temperature difference before time Ns, that is, Xgn-Xg=Δg;

[0030] Determine the automatic control stage. If it is in the temperature stabilization stage, go to step 2. If it is in the temperature rise stage, go to step 5. Step 2,

[0031] When Δg>0, go to step 3;

[0032] When Δg<0, go to step 4;

[0033] When Δg=0:

[0034] Increase or decrease of air supply motor opening = K*(Δs*100+Δd) / 2;

[0035] The increase or decrease of the air outlet motor opening amount = 0;

[0036] Step 3:

[0037] The increase or decrease of the air supply motor opening amount = 0;

[0038] The increase or decrease of the opening of the air outlet motor = K*(Δs*100+Δd) / 2;

[0039] Step 4:

[0040] Increase or decrease of air supply motor opening = K*(Δs*100+Δd) / 2

[0041] The increase or decrease of the air outlet motor opening amount = 0;

[0042] Step 5:

[0043] When Δg>0, go to step 6;

[0044] When Δg<0, go to step 7;

[0045] When Δg=0:

[0046] Increase or decrease of air supply motor opening = K*(Δs*100);

[0047] The increase or decrease of the air outlet motor opening amount = 0;

[0048] Step 6:

[0049] The increase or decrease of the air supply motor opening amount = 0;

[0050] The increase or decrease of the air outlet motor opening amount = 0;

[0051] Step 7:

[0052] Increase or decrease of air supply motor opening = K*(Δs*100) / 2;

[0053] The increase or decrease in the opening of the air outlet motor = K*(Δs*100) / 2.

[0054] As a further improvement of the present invention, the increase or decrease amount of the air supply motor and the air outlet motor are taken as integers. When it is a positive number, the number of the air supply motors / air outlet motors turned on is increased; when it is a negative number, the number of the air supply motors / air outlet motors turned on is reduced; when it is between -1 and 1, the current number of turned on is maintained.

[0055] As a further improvement of the present invention, the baking room body is an airflow descending baking room, the air outlet is arranged on the upper side, the air supply port is arranged on the lower side, the height of the air outlet is Hc, the unit is cm, the height of the air supply port is Hb, the unit is cm, K=Hc-20 / Hb+100.

[0056] As a further improvement of the present invention, the baking room body is an airflow rising baking room, the air outlet is arranged on the upper side, the air supply port is arranged on the lower side, the height of the air outlet is Hc, the unit is cm, the height of the air supply port is Hb, the unit is cm, K=Hc-20 / Hb+110.

[0057] The beneficial effects of the present invention are that the air supply blade and the air outlet blade are controlled separately, the air outlet and air inlet are adjusted linearly, and the dehumidification is controlled to control the actual dry-bulb temperature, wet-bulb temperature and relative humidity data in the curing room with higher accuracy. It is prevented that the dry-bulb temperature, wet-bulb temperature or relative humidity in the curing room hovers around the target value, so that the dry-bulb temperature, wet-bulb temperature or relative humidity data in the curing room are highly consistent with the target value, and the situation of insufficient dehumidification and excessive dehumidification is avoided, and the tobacco leaves are prevented from being damaged by baking, and unnecessary baking losses are eliminated. At the same time, the quality of tobacco leaves can be improved, energy consumption can be reduced, and economic benefits can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 It is a structural schematic diagram of a baking room with rising airflow;

[0059] Figure 2 It is a structural schematic diagram of a baking room with downward airflow;

[0060] Figure 3 This is a schematic diagram of the plane structure of the air supply port;

[0061] Figure 4 This is a schematic diagram of the plane structure of the air outlet.

[0062] Marking instructions: 1. Baking room body; 2. Heating chamber; 3. Air supply port; 31. Air supply louver; 32. Air supply blade; 33. Air supply motor; 4. Air outlet; 41. Air outlet louver; 42. Air outlet blade; 43. Air outlet motor. DETAILED DESCRIPTION

[0063] The present invention will be further described below in detail with reference to the embodiments shown in the accompanying drawings.

[0064] Reference Figure 1-Figure 4As shown, a precise humidity control equipment for improving the baking quality of tobacco leaves in this embodiment includes a baking room body 1 and a heating chamber 2 arranged in the baking room body 1, the baking room body 1 is provided with an air supply port 3 and an air outlet 4, the air supply port 3 is provided with an air supply louver 31, the air supply louver 31 is composed of a plurality of rotatable air supply blades 32, the air outlet 4 is provided with an air outlet louver 41, the air outlet louver 41 is composed of a plurality of rotatable air outlet blades 42, the baking room is provided with a waterless intelligent dry-wet bulb sensor and an automatic control instrument, the air supply port 3 is provided with a plurality of air supply blades 32, and the air outlet 4 is provided with an air outlet louver 41. The wind motor 33, the number of the air supply motors 33 is the same as the number of the air supply blades 32, and the air supply motors 33 are connected to the air supply blades 32 in a one-to-one correspondence. The air outlet 4 is provided with a plurality of air outlet motors 43, the number of the air outlet motors 43 is the same as the number of the air outlet blades 42, and the air outlet motors 43 are connected to the air outlet blades 42 in a one-to-one correspondence. The automatic control instrument is connected to the waterless intelligent dry-bulb and wet-bulb sensor, the air supply motor 33, and the air outlet motor 43. The waterless intelligent dry-bulb and wet-bulb sensor outputs dry-bulb temperature data, wet-bulb temperature data and relative humidity data to the automatic control instrument.

[0065] Specifically, the waterless intelligent dry-wet bulb sensor adopts another patent of the applicant:

[0066] ZL202322048394.5, water-free intelligent wet-dry bulb sensor for tobacco leaf baking.

[0067] Through the above technical solution, when the actual dry-bulb temperature, wet-bulb temperature or relative humidity data in the curing room body 1 deviates from the target dry-bulb temperature, wet-bulb temperature or relative humidity data, the automatic control instrument outputs a control signal to control the air supply motor 33 and the air outlet motor 43 to operate, and then control the air supply blades 32 and the air outlet blades 42 to rotate. Since the air supply motor 33 and the air supply blades 32 correspond one to one, and the air outlet motor 43 and the air outlet blades 42 correspond one to one, the rotation of each air supply blade 32 and the air outlet blade 42 can be controlled separately, and then the air outlet and air intake can be linearly adjusted. When controlling the actual dry-bulb temperature, wet-bulb temperature and relative humidity data in the curing room body 1, the accuracy is higher. Avoid the dry-bulb temperature and wet-bulb temperature in the curing room to hover around the target value, so that the dry-bulb temperature and wet-bulb temperature in the curing room are highly consistent with the target value, avoid insufficient and excessive dehumidification, avoid bad tobacco leaves, and eliminate unnecessary baking losses. At the same time, it can improve the quality of tobacco leaves and improve economic benefits.

[0068] Excessive dehumidification will lower the temperature in the curing room, and then the electric heating device in the heating chamber 2 needs to raise the temperature in the curing room again, which requires increasing the power, resulting in high energy consumption and waste in tobacco curing. The present application has precise control, avoids unnecessary heat loss, reduces energy consumption in the tobacco curing process, and saves energy and reduces emissions.

[0069] There are A air supply motors 33, and the i-th air supply motor 33 is defined as Di, wherein i is a natural number between 1 and A, and the i-th air supply motor 33 has two on and off states, Di=1 for on; Di=0 for off;

[0070] There are B air outlet motors 43, and the mth air outlet motor 43 is defined as Em, where m is a natural number between 1 and B. The mth air outlet motor 43 has two opening and closing states: Em=1 for opening; and Em=0 for closing.

[0071] The opening and closing state of the air supply motor 33 represents the opening and closing state of the air supply blades 32, and the opening and closing state of the air outlet motor 43 represents the opening and closing state of the air outlet blades 42;

[0072] According to the set program, the corresponding number of air supply motors and air outlet motors are turned on in different stages.

[0073] The control method of precise humidity control equipment is as follows:

[0074] First, determine the target dry-bulb temperature of the flue-curing room as Lg, and the target wet-bulb temperature as Ls. The waterless intelligent dry-bulb and wet-bulb sensor for tobacco leaf curing (ZL202322048394.5) will calculate the target relative humidity range as Ld1~Ld2 in combination with the environment in the flue-curing room, Lg and Ls (in the flue-curing room, the same set of target dry-bulb and wet-bulb temperatures corresponds to a relative air humidity range, Ld1~Ld2=);

[0075] Assume: Lg1 = Lg + 0.1

[0076] Ls1=Ls-0.1

[0077] Ld1=(e^(ln611.2+A*Ls1 / (B+Ls1))-P*(Lg1-Ls1)) / e^(ln611.2+A*Lg1 / (B+Lg1))

[0078] Assume: Lg2 = Lg-0.1

[0079] Ls2=Ls+0.1

[0080] Ld2=(e^(ln611.2+A*Ls2 / (B+Ls2))-P*(Lg2-Ls2)) / e^(ln611.2+A*Lg2 / (B+Lg2))

[0081] Where: A is the temperature constant in the range of 30℃-100℃

[0082] B is the absolute temperature corresponding to 30℃

[0083] e is the base of natural logarithm ≈ 2.71828

[0084] P is the pressure interval constant

[0085] The actual dry-bulb temperature of the current baking room is read as Mg, the actual wet-bulb temperature is Ms, and the actual relative humidity is Md; among which, the target dry-bulb temperature is Lg, the target wet-bulb temperature is Ls, the actual dry-bulb temperature is Mg, and the actual wet-bulb temperature is Ms rounded; the supply air / exhaust air ratio coefficient is determined as K; the exhaust air coefficient K is calculated differently when the airflow in the baking room is ascending or descending.

[0086] In the case of a downward airflow baking room, when the air outlet 4 is arranged on the upper side and the air supply port 3 is arranged on the lower side, the height of the air outlet 4 is Hc, in cm, and the height of the air supply port 3 is Hb, in cm.

[0087] K=Hc-20 / Hb+100.

[0088] In the case of a rising airflow oven, the air outlet 4 is set at the upper side and the air supply port 3 is set at the lower side, the height of the air outlet 4 is Hc, in cm, and the height of the air supply port 3 is Hb, in cm.

[0089] K=Hc-20 / Hb+110.

[0090] Calculate the difference between the target dry bulb temperature Lg and the actual dry bulb temperature Mg, i.e. Lg-Mg=Xg;

[0091] Calculate the difference between the target wet bulb temperature Ls and the actual wet bulb temperature Ms, that is, Ls-Ms=Xs;

[0092] Calculate the difference between the target relative humidity Ld and the actual relative humidity, i.e. 100*(Ld-Md)=Xd;

[0093] Calculate the dry-bulb temperature difference and the dry-bulb temperature difference before time Ns, that is, Xgn-Xg=Δg; when Δg=0, the drying room temperature is constant; when Δg>0, the drying room temperature is decreasing; when Δg<0, the drying room temperature is rising.

[0094] Calculate the wet-bulb temperature difference and the wet-bulb temperature difference before time Ns, that is, Xsn-Xs=Δs.

[0095] Calculate the relative humidity difference and the relative humidity difference before time Ns, that is, Xdn-Xd=Δd.

[0096] During the temperature stabilization stage of the automatic controller:

[0097] When Δg=0, the oven temperature is constant:

[0098] The increase or decrease of the opening of the air supply motor 33 = K*(Δs*100+Δd) / 2

[0099] The air outlet motor 43 is turned on and off by an amount equal to 0.

[0100] When Δg>0, the drying room temperature is decreasing.

[0101] Air supply motor 33 opening increase or decrease amount = 0

[0102] The increase or decrease of the opening of the air outlet motor 43 = K*(Δs*100+Δd) / 2

[0103] When Δg<0, the drying room temperature is rising.

[0104] The increase or decrease of the opening of the air supply motor 33 = K*(Δs*100+Δd) / 2

[0105] The air outlet motor 43 is turned on and off by an amount equal to 0.

[0106] During the temperature rise phase of the automatic controller:

[0107] When Δg=0, the drying room temperature rises in accordance with the temperature rise curve:

[0108] The increase or decrease of the opening of the air supply motor 33 = K*(Δs*100)

[0109] The air outlet motor 43 is turned on and off by an amount equal to 0.

[0110] When Δg>0, the drying room temperature cannot keep up with the heating curve.

[0111] Air supply motor 33 opening increase or decrease amount = 0

[0112] The air outlet motor 43 is turned on and off by an amount equal to 0.

[0113] Increase the power of the heating element in heating chamber 2

[0114] When Δg<0, the drying room temperature has exceeded the limit.

[0115] The increase or decrease of the opening of the air supply motor 33 = K*(Δs*100) / 2

[0116] The increase or decrease of the opening of the air outlet motor 43 = K*(Δs*100) / 2

[0117] The increase and decrease of the opening of the air supply motor 33 and the opening of the air outlet motor 43 are integers. When it is a positive number, the number of the air supply motors 33 / air outlet motors 43 turned on is increased. When it is a negative number, the number of the air supply motors 33 / air outlet motors 43 turned on is reduced. When it is between -1 and 1, the current opening number is maintained. Specifically, the current number of air supply motors turned on is i, and the number of air outlet motors turned on is e. If the increase and decrease of the opening of the air supply motor 33 = 0; the increase and decrease of the opening of the air outlet motor 43 = -1.1, then i air supply motors are turned on and e-1 air outlet motors are turned on.

[0118] When the automatic controller is in the temperature stabilization stage, the temperature of the baking room rises and the wet-bulb temperature inside the baking room is controlled by adjusting the number of openings of the air supply motor 33; and when the automatic controller is in the temperature rise stage, the temperature of the baking room rises and the wet-bulb temperature inside the baking room is controlled by simultaneously adjusting the number of openings of the air supply motor 33 and the air outlet motor 43.

[0119] Using different control strategies at different stages and under different heating and cooling conditions can improve the accuracy of control in the curing room, making the wet-bulb temperature closer to the target value, thereby improving the quality of tobacco leaves.

[0120] At the same time, the recording time Ns can be appropriately adjusted according to the smoke loading in the baking room, so as to effectively control the wet-bulb temperature while maintaining the positive pressure in the baking room and avoid the wet-bulb temperature from fluctuating up and down.

[0121] It should be pointed out that at different stages of tobacco curing, the target dry-bulb temperature Lg, the target wet-bulb temperature Ls, and the target relative humidity Ld are different.

[0122] Setting the exhaust coefficient K so that the opening degree of the air supply port 3 is greater than that of the air outlet 4 can increase the positive pressure at the upper position in the curing room, that is, the air outlet position, thereby improving the uniformity of temperature and humidity in the horizontal and vertical directions in the curing room, avoiding the problem of poor ventilation between tobacco leaves in the curing room, and making an important contribution to improving the homogenization level of the whole cured tobacco leaves. The exhaust coefficient K is related to the height of the air supply port 3 and the air outlet 4, and the direction of the air flow. Adjusting the exhaust coefficient K according to the curing rooms of different specifications can further improve the dehumidification efficiency and the homogenization level of the whole cured tobacco leaves.

[0123] The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A precise humidity control device for improving the quality of tobacco leaf baking, comprising a baking room body (1) and a heating chamber (2) arranged in the baking room body (1), the baking room body (1) being provided with an air supply port (3) and an air outlet (4), the air supply port (3) being provided with an air supply louver (31), the air supply louver (31) being composed of a plurality of rotatable air supply blades (32), the air outlet (4) being provided with an air outlet louver (41), the air outlet louver (41) being composed of a plurality of rotatable air outlet blades (42), characterized in that: The baking room is provided with a waterless intelligent dry-wet-bulb sensor and an automatic control device. The air supply port (3) is provided with a plurality of air supply motors (33). The number of the air supply motors (33) is the same as the number of the air supply blades (32). The air supply motors (33) are connected to the air supply blades (32) in a one-to-one correspondence. The air outlet (4) is provided with a plurality of air outlet motors (43). The number of the air outlet motors (43) is the same as the number of the air outlet blades (42). The air outlet motors (43) are connected to the air outlet blades (42) in a one-to-one correspondence. The automatic control device is connected to the waterless intelligent dry-wet-bulb sensor, the air supply motor (33), and the air outlet motor (43). The waterless intelligent dry-wet-bulb sensor outputs dry-bulb temperature data, wet-bulb temperature data, and relative humidity data to the automatic control device.

2. A method for controlling the precise humidity control equipment according to claim 1, characterized in that: There are A air supply motors (33), and the i-th air supply motor (33) is defined as Di, wherein i is a natural number between 1 and A, and the i-th air supply motor (33) has two opening and closing states, Di=1 for opening; Di=0 for closing; There are B air outlet motors (43), and the mth air outlet motor (43) is defined as Em, wherein m is a natural number between 1 and B, and the mth air outlet motor (43) has two opening and closing states, Em=1 for opening; and Em=0 for closing; According to the set program, corresponding numbers of air supply motors (33) and air outlet motors (43) are turned on at different stages.

3. A method for controlling the precise humidity control equipment according to claim 1, characterized in that: Setting the increase and decrease amount of the air supply motor (33) and the increase and decrease amount of the air outlet motor (43), and then controlling the number of times the air supply motor (33) and the air outlet motor (43) are turned on according to the increase and decrease amount of the air supply motor (33) and the air outlet motor (43); The calculation method of the increase and decrease of the opening amount of the air supply motor (33) and the increase and decrease of the opening amount of the air outlet motor (43) is as follows: Step 1: The same set of target dry-bulb and wet-bulb temperatures in the oven corresponds to a relative air humidity range, Ld1~Ld2=); Lg1=Lg+0.1 Ls1=Ls-0.1 Ld1=(e^(ln611.2+A*Ls1 / (B+Ls1))-P*(Lg1-Ls1)) / e^(ln611.2+A*Lg1 / (B+Lg1)) Assume: Lg2 = Lg-0.1 Ls2=Ls+0.1 Ld2=(e^(ln611.2+A*Ls2 / (B+Ls2))-P*(Lg2-Ls2)) / e^(ln611.2+A*Lg2 / (B+Lg2)) Where: A is the temperature constant in the range of 30℃-100℃ B is the absolute temperature corresponding to 30℃ e is the base of natural logarithm ≈ 2.71828 P is the pressure interval constant Determine the target dry bulb temperature of the oven as Lg and the target wet bulb temperature as Ls; read the actual dry bulb temperature of the oven as Mg, the actual wet bulb temperature as Ms, and the actual relative humidity as Md; where the target dry bulb temperature is Lg, the target wet bulb temperature is Ls, the actual dry bulb temperature is Mg, and the actual wet bulb temperature is Ms, rounded; determine the air supply / exhaust ratio coefficient as K; Calculate the difference between the target dry bulb temperature Lg and the actual dry bulb temperature Mg, i.e. Lg-Mg=Xg; Calculate the difference between the target wet bulb temperature Ls and the actual wet bulb temperature Ms, that is, Ls-Ms=Xs; Calculate the difference between the target relative humidity Ld and the actual relative humidity Md, that is, 100*(Ld-Md)=Xd; Calculate the wet bulb temperature difference and the wet bulb temperature difference before time Ns, that is, Xsn-Xs=Δs; Calculate the relative humidity difference and the relative humidity difference before time Ns, that is, Xdn-Xd=Δd; Calculate the dry bulb temperature difference and the dry bulb temperature difference before time Ns, that is, Xgn-Xg=Δg; Determine the automatic control stage. If it is in the temperature stabilization stage, go to step 2. If it is in the temperature rise stage, go to step 5. Step 2, When Δg>0, go to step 3; When Δg<0, go to step 4; When Δg=0: The increase or decrease of the opening of the air supply motor (33) = K*(Δs*100+Δd) / 2; The air outlet motor (43) is turned on and off by increasing or decreasing amount = 0; Step 3: The increase or decrease amount of the air supply motor (33) is turned on = 0; The increase or decrease of the opening of the air outlet motor (43) = K*(Δs*100+Δd) / 2; Step 4: The increase or decrease of the opening of the air supply motor (33) = K*(Δs*100+Δd) / 2 The air outlet motor (43) is turned on and off by increasing or decreasing amount = 0; Step 5: When Δg>0, go to step 6; When Δg<0, go to step 7; When Δg=0: The increase or decrease of the opening of the air supply motor (33) = K*(Δs*100); The air outlet motor (43) is turned on and off by increasing or decreasing amount = 0; Step 6: The increase or decrease amount of the air supply motor (33) is turned on = 0; The air outlet motor (43) is turned on and off by increasing or decreasing amount = 0; Step 7: The increase or decrease of the opening of the air supply motor (33) = K*(Δs*100) / 2; The increase or decrease amount of opening of the air outlet motor (43) = K*(Δs*100) / 2.

4. The control method of the precise humidity control equipment according to claim 3, characterized in that: The increase or decrease amount of the air supply motor (33) and the air outlet motor (43) are taken as integers. When it is a positive number, the number of the air supply motor (33) / air outlet motor (43) turned on is increased. When it is a negative number, the number of the air supply motor (33) / air outlet motor (43) turned on is reduced. When it is between -1 and 1, the current number of turned on is maintained.

5. The control method of the precise humidity control equipment according to claim 3, characterized in that: The baking room body is an airflow descending baking room, the air outlet (4) is arranged on the upper side, the air supply port (3) is arranged on the lower side, the height of the air outlet (4) is Hc, in cm, the height of the air supply port (3) is Hb, in cm, and K=Hc-20 / Hb+100.

6. The control method of the precise humidity control equipment according to claim 3, characterized in that: The baking room body is an airflow rising baking room, the air outlet (4) is arranged on the upper side, the air supply port (3) is arranged on the lower side, the height of the air outlet (4) is Hc, in cm, the height of the air supply port (3) is Hb, in cm, and K=Hc-20 / Hb+110.

Images