A method for experimentally obtaining a material moisture control model of a silk reeling leaf conditioning machine

Abstract

The present invention discloses a method for experimentally obtaining a material moisture control model of a leaf conditioning machine in cigarette leaf processing, belonging to the technical field of cigarette leaf processing. The method includes entering the production stage when the leaf conditioning machine meets the production conditions; performing moisture control on the leaf conditioning machine during the production stage, and defining the stable stage of the moisture control of the leaf conditioning machine in a formulaic form; when the moisture control of the leaf conditioning machine enters the stable stage, approximating the non-linear time-varying system as a linearized constant system to obtain the material moisture control model of the leaf conditioning machine in cigarette leaf processing. The present invention solves the problems that the moisture control in the existing leaf conditioning process is relatively complex and the control strategy adopted for the purpose of improving the control model lacks an accurate mathematical model. The properties and parameters of an accurate mathematical model can be approximated during the relatively stable stage of the production process, thereby obtaining the stability, stability margin, accuracy, and time-domain fast response characteristics of the material moisture control model of the leaf conditioning machine in cigarette leaf processing, so as to further improve and correct the accurate mathematical model.

Description

Technical Field

[0001] The present invention relates to the technical field of cigarette cut tobacco processing, and particularly to a method for experimentally obtaining a material moisture control model of a leaf conditioning machine for cut tobacco processing. Background Art

[0002] The leaf conditioning process is an important process in the cigarette cut tobacco processing technology. By increasing the temperature and humidity of the tobacco leaves, the tobacco leaves are completely loosened and reach a certain temperature and humidity to meet the technological requirements of subsequent processing, and at the same time, the toughness and processability of the tobacco leaves are improved. By adjusting the frequency of the water pump, the purpose of controlling the moisture content of the tobacco leaves is achieved.

[0003] Since the leaf conditioning and humidification process has strong non-linearity, uncertainty and large lag, and combined with the special properties of the tobacco leaves themselves, the moisture control of the leaf conditioning process becomes very complicated. Essentially, the material moisture control of the leaf conditioning machine for cut tobacco processing belongs to a non-linear time-varying system, and can be approximately regarded as a linear time-invariant system in some relatively stable production processes. And control strategies such as time-delay Smith control, fuzzy control, neural network, adaptive control, predictive control, etc. adopted for the purpose of improving the control model often require an accurate mathematical model. Summary of the Invention

[0004] The purpose of the present invention is to overcome the deficiencies in the prior art, and provide a method for experimentally obtaining a material moisture control model of a leaf conditioning machine for cut tobacco processing, to solve the problem that the moisture control in the leaf conditioning process in the prior art is relatively complicated, and the control strategies adopted for the purpose of improving the control model lack an accurate mathematical model, and approximate the properties and parameters of an accurate mathematical model in a relatively stable production process, thereby obtaining the stability, stability margin, accuracy and time-domain fast response characteristics of the material moisture control model of the leaf conditioning machine for cut tobacco processing, so as to further improve and correct the accurate mathematical model.

[0005] To achieve the above purpose, the present invention is implemented by adopting the following technical solution:

[0006] The present invention provides a method for experimentally obtaining a material moisture control model of a leaf conditioning machine for cut tobacco processing, including:

[0007] Enter the production stage when the leaf conditioning machine meets the production conditions;

[0008] Conduct moisture control on the leaf conditioning machine in the production stage, and define the stable stage of the moisture control of the leaf conditioning machine in a formulaic form;

[0009] When the moisture control of the leaf conditioning machine enters the stable stage, approximate the non-linear time-varying system as a linearized time-invariant system, and obtain the material moisture control model of the leaf conditioning machine for cut tobacco processing.

[0010] Further, the conducting moisture control on the leaf conditioning machine in the production stage includes:

[0011] The PID control module is used to control the inlet water addition control, outlet water replenishment and addition control, hot air control, exhaust negative pressure control, and direct injection steam control in the moisture control loop of the leaf conditioning machine;

[0012] The set value SP in the PID control module is defined as the preset set value of the moisture control loop in the production stage, and the preset set value includes equipment parameters and / or formula parameters.

[0013] Furthermore, the moisture control of the leaf conditioning machine in the production stage further includes:

[0014] When the outlet infrared moisture meter detects the material moisture value at the outlet, the outlet water replenishment and addition control is used as the main material moisture control loop; the outlet water replenishment and addition control is used to control the outlet material moisture;

[0015] Cancel the preset set value of the outlet water replenishment and addition control loop, and feedback the material moisture value at the outlet to the set value SP of the outlet water replenishment and addition PID control loop in a PID cascade manner for closed-loop control.

[0016] Furthermore, the definition of the stable stage of the moisture control of the leaf conditioning machine includes:

[0017] The inlet water addition control 1 in the corresponding outlet material moisture control loop of the leaf conditioning machine # PID loop and the outlet water replenishment and addition control 2 # The PID loop enters the moisture control stable state;

[0018] Among them, within the time duration of time1 for the inlet water addition control 1 # The absolute value of the difference between the mean value of the set value SP1 and the actual value PV1 of the PID loop is lower than the threshold value TV1, and the standard deviation value SD1 of the actual value PV1 within the time duration of time1 is lower than the threshold value TV2;

[0019] Within the time duration of time2 for the outlet water replenishment and addition control 2 # The absolute value of the difference between the mean value of the set value SP2 and the actual value PV2 of the PID loop is lower than the threshold value TV3, and the standard deviation value SD2 of the actual value PV2 within the time duration of time2 is lower than the threshold value TV4.

[0020] Furthermore, the definition formula of the stable stage of the moisture control of the leaf conditioning machine includes:

[0021] For the inlet water addition control 1 # PID loop, within the time duration of time1:

[0022] ;

[0023] Wherein, is the mean value of the actual value PV1 of the water addition at the inlet during the stable stage of the moisture control of the leaf conditioning machine, SP1 is the set value of the water addition at the inlet during the stable stage of the moisture control of the leaf conditioning machine, and TV1 is the inlet water addition control 1 # threshold of the PID loop;

[0024] The calculation formula of

[0025] ;

[0026] Wherein, n1 is the number of the actual values PV1 of the water addition at the inlet during the stable stage of the moisture control of the leaf conditioning machine, is the sum of the actual values PV1 of the water addition at the inlet during the stable stage of the moisture control of the leaf conditioning machine;

[0027] The calculation formula of SD1 is:

[0028] ;

[0029] Wherein, SD1 is the standard deviation of the actual value PV1 of the water addition at the inlet during the stable stage of the moisture control of the leaf conditioning machine, X i is the single sample value of the actual value PV1 of the water addition at the inlet during the stable stage of the moisture control of the leaf conditioning machine;

[0030] During the time with a duration of time l, ; TV2 is the inlet water addition control 1 # threshold of the PID loop;

[0031] For the outlet water replenishment water addition control 2 # PID loop, during the time with a duration of time2:

[0032] ;

[0033] Wherein, is the mean value of the actual value PV2 of the outlet water replenishment during the stable stage of the moisture control of the leaf conditioning machine, SP2 is the set value of the outlet water replenishment during the stable stage of the moisture control of the leaf conditioning machine, and TV3 is the outlet water replenishment water addition control 2 # threshold of the PID loop;

[0034] The calculation formula of

[0035] ;

[0036] Wherein, n2 is the number of actual values PV2 of the outlet makeup water volume during the stable stage of the moisture control of the leaf conditioning machine, is the sum of the actual values PV2 of the outlet makeup water volume during the stable stage of the moisture control of the leaf conditioning machine;

[0037] The calculation formula of SD2 is:

[0038] ;

[0039] Wherein, SD2 is the standard deviation of the actual value PV2 of the outlet makeup water volume during the stable stage of the moisture control of the leaf conditioning machine, and Y i is a single sample value of the actual value PV2 of the outlet makeup water volume during the stable stage of the moisture control of the leaf conditioning machine;

[0040] During the time with a duration of time2, ; TV4 is the threshold of the outlet makeup water and water addition control 2 # PID loop of the leaf conditioning machine during the stable stage of moisture control.

[0041] Furthermore, the definition of the stable stage of the moisture control of the leaf conditioning machine further includes:

[0042] Keep the inlet water addition control relatively stable and the outlet makeup water and water addition control relatively stable; keep the hot air control, exhaust negative pressure control and direct injection steam control relatively stable;

[0043] The relatively stable inlet water addition control includes that the output value CV1 of the inlet water addition control 1 # PID loop remains lower than the threshold TV5, and the relatively stable outlet makeup water and water addition control includes that the output value CV2 of the outlet makeup water and water addition control 2 # PID loop remains lower than the threshold TV6;

[0044] The maintenance of the relative stability of the hot air control, exhaust negative pressure control and direct injection steam control includes that the hot air temperature control loop 3 # PID loop, exhaust negative pressure 4 # PID loop and direct injection steam 5 # PID loop enter the moisture stable state;

[0045] Among them, during the time with a duration of time4, the absolute value of the difference between the set value SP3 and the mean value of the actual value PV3 of the hot air temperature control 3 # PID loop is lower than the threshold TV7; the standard deviation SD3 of the actual value PV3 during the time with a duration of time4 is lower than the threshold TV8; the exhaust negative pressure 4 #The absolute value of the difference between the set value SP4 of the PID loop and the mean value of the actual value PV4 is lower than the threshold value TV9; the standard deviation SD4 of the actual value PV4 within the duration of time5 is lower than the threshold value TV 10 ; within the duration of time6 for the direct injection steam 5 # The absolute value of the difference between the set value SP5 of the PID loop and the mean value of the actual value PV5 is lower than the threshold value TV 11 ; the standard deviation SD5 of the actual value PV5 within the duration of time6 is lower than the threshold value TV 12 .

[0046] Furthermore, the definition formula for the stable stage of the moisture control of the leaf conditioning machine further includes:

[0047] , and the duration exceeds time3;

[0048] , and the duration exceeds time3;

[0049] In the formula, CV1 is the inlet water addition control 1 for the stable stage of the moisture control of the leaf conditioning machine # Output value of the PID loop, CV2 is the outlet water replenishment and addition control 2 for the stable stage of the moisture control of the leaf conditioning machine # Output value of the PID loop, TV5 is the inlet water addition control 1 for the stable stage of the moisture control of the leaf conditioning machine # Threshold value of the PID loop, TV6 is the outlet water replenishment and addition control 2 for the stable stage of the moisture control of the leaf conditioning machine # Threshold value of the PID loop;

[0050] For the hot air temperature control 3 # PID loop, within the duration of time4:

[0051] ;

[0052] In the formula, is the mean value of the actual value PV3 of the hot air temperature for the stable stage of the moisture control of the leaf conditioning machine, SP3 is the set value of the hot air temperature for the stable stage of the moisture control of the leaf conditioning machine, TV7 is the hot air temperature control 3 for the stable stage of the moisture control of the leaf conditioning machine # Threshold value of the PID loop;

[0053] The calculation formula of is:

[0054] ;

[0055] In the formula, n3 is the number of the actual values PV3 of the hot air temperature for the stable stage of the moisture control of the leaf conditioning machine, It is the sum of the actual values PV3 of the hot air temperature in the stable stage of the moisture control of the leaf conditioning machine;

[0056] The calculation formula of SD3 is:

[0057] ;

[0058] In the formula, SD3 is the standard deviation of the actual value PV3 of the hot air temperature in the stable stage of the moisture control of the leaf conditioning machine, and W i is the single sample value of the actual value PV3 of the hot air temperature in the stable stage of the moisture control of the leaf conditioning machine;

[0059] Within the time duration of time4, ; TV8 is the threshold of the hot air temperature control 3 # PID loop of the leaf conditioning machine;

[0060] For the exhaust negative pressure 4 # PID loop, within the time duration of time5:

[0061] ;

[0062] In the formula, is the mean value of the actual value PV4 of the exhaust negative pressure in the stable stage of the moisture control of the leaf conditioning machine, SP4 is the set value of the exhaust negative pressure in the stable stage of the moisture control of the leaf conditioning machine, and TV9 is the exhaust negative pressure 4 # PID loop threshold of the leaf conditioning machine;

[0063] The calculation formula of is:

[0064] ;

[0065] In the formula, n4 is the number of the actual value PV4 of the exhaust negative pressure in the stable stage of the moisture control of the leaf conditioning machine, is the sum of the actual value PV4 of the exhaust negative pressure in the stable stage of the moisture control of the leaf conditioning machine;

[0066] The calculation formula of SD4 is:

[0067] ;

[0068] In the formula, SD4 is the standard deviation of the actual value PV4 of the exhaust negative pressure in the stable stage of the moisture control of the leaf conditioning machine, and Z i is the single sample value of the actual value PV4 of the exhaust negative pressure in the stable stage of the moisture control of the leaf conditioning machine;

[0069] Within the time duration of time5, ; TV 10The exhaust negative pressure 4 in the stable stage of the moisture control of the leaf conditioning machine # The threshold of the PID loop;

[0070] For direct injection steam 5 # PID loop, within the time duration of time6:

[0071] ;

[0072] In the formula, is the mean value of the actual value PV5 of the direct injection steam in the stable stage of the moisture control of the leaf conditioning machine, SP5 is the set value of the direct injection steam in the stable stage of the moisture control of the leaf conditioning machine, and TV 11 is the direct injection steam 5 in the stable stage of the moisture control of the leaf conditioning machine # The threshold of the PID loop;

[0073] The calculation formula of is:

[0074] ;

[0075] In the formula, n5 is the number of the actual values PV5 of the direct injection steam in the stable stage of the moisture control of the leaf conditioning machine, is the sum of the actual values PV5 of the direct injection steam in the stable stage of the moisture control of the leaf conditioning machine;

[0076] The calculation formula of SD5 is:

[0077] ;

[0078] In the formula, SD5 is the standard deviation value of the actual value PV5 of the direct injection steam in the stable stage of the moisture control of the leaf conditioning machine, and G i is the single sample value of the actual value PV5 of the direct injection steam in the stable stage of the moisture control of the leaf conditioning machine;

[0079] Within the time duration of time6, , TV 12 is the direct injection steam 5 in the stable stage of the moisture control of the leaf conditioning machine # The threshold of the PID loop.

[0080] Furthermore, the definition of the stable stage of the moisture control of the leaf conditioning machine also includes:

[0081] Keep the control of the hot air temperature control loop, the opening of the exhaust negative pressure valve and the control of the direct injection steam control loop relatively stable; keep the moisture of the material at the outlet of the leaf conditioning machine in a stable controlled state;

[0082] The relatively stable control of the hot air temperature control loop includes that the output value CV3 of the hot air temperature control 3 # PID loop remains lower than the threshold TV13 and last for a time period of time7;

[0083] The opening of the exhaust moisture negative pressure valve is relatively stable, including the exhaust moisture negative pressure 4 # The output value CV4 of the PID loop remains lower than the threshold value TV 14 and last for a time period of time8;

[0084] The direct injection steam control loop is relatively stable, including the direct injection steam 5 # The output value CV5 of the PID loop remains lower than the threshold value TV 15 and last for a time period of time9;

[0085] The moisture content of the material at the outlet of the leaf conditioning machine is in a stable and controlled state, including the actual value of the outlet material temperature and the controlled required value The absolute value of the difference is kept lower than the threshold value TV 16 ; the actual value of the moisture content of the outlet material and the controlled required value The absolute value of the difference is kept lower than the threshold value TV 17 .

[0086] Furthermore, the definition formula for the stable stage of the moisture control of the leaf conditioning machine also includes:

[0087] , and the continuous duration exceeds time7;

[0088] , and the continuous duration exceeds time8;

[0089] , and the continuous duration exceeds time9;

[0090] , and the continuous duration exceeds time 10 ;

[0091] , and the continuous duration exceeds time 11 ;

[0092] In the formula, CV3 is the output value of the PID loop for the hot air temperature control 3 # CV4 is the output value of the PID loop for the exhaust moisture negative pressure 4 # CV5 is the output value of the PID loop for the direct injection steam 5 # PID loop output value, TV 13 is the threshold value of the PID loop for the hot air temperature control 3 # TV 14 is the threshold value of the PID loop for the exhaust moisture negative pressure 4 # PID loop threshold value, TV15 is direct injection steam 5 # The threshold value of the PID loop, TV 16 and TV 17 is the moisture-related value corresponding to the outlet is the actual value of the outlet material temperature is the controlled required value of the outlet material temperature is the actual value of the outlet material moisture is the controlled required value of the outlet material moisture

[0093] Further, the method for obtaining the material moisture control model of the cigarette making and leaf conditioning machine includes:

[0094] Give a fixed increment value to the frequency value of the makeup water and water addition control output of the outlet, and simulate it into a stable step signal

[0095] Record the data of the actual value of the outlet material moisture changing with time t, and fit it into a curve using a computer algorithm

[0096] Calculate the parameter values in the transfer function of the first-order plus lag control model by reverse calculation through the curve, and obtain an approximate first-order lag model. The approximate first-order lag model is the material moisture control model of the cigarette making and leaf conditioning machine

[0097] The material moisture control model of the cigarette making and leaf conditioning machine is:

[0098] ;

[0099] In the formula, K is the static amplification coefficient, Ts is the time constant is the model lag time, s is the Laplace transform factor is the transfer function of the material moisture control model of the cigarette making and leaf conditioning machine

[0100] Compared with the prior art, the beneficial effects achieved by the present invention:

[0101] The present invention discloses a method for experimentally obtaining a material moisture control model of a tobacco leaf conditioning machine. It defines the stable stage of moisture control of the conditioning machine in a formulaic form, effectively identifies the stage and application scenarios of a constant system that can be approximated as linearized, and obtains an accurate mathematical model for the material moisture control of the tobacco leaf conditioning machine in the stable production stage. This model can be used when production enters a stable state. By means of the method of cascading PID feedback to correct the outlet water replenishment set value, the moisture control of the tobacco leaf conditioning process material can be effectively stabilized. By connecting two single feedback PIDs in series and combining the method of cumulative correction, the defined stable stage of moisture control of the conditioning machine is closer to the actual situation and more effectively conforms to the processing characteristics of the tobacco cylinder device, with good realizability. In the industry, it can be carried out simultaneously with physical commissioning without wasting additional tobacco material resources. Compared with traditional PID control, this method can approximate the properties and parameters of an accurate mathematical model. Based on the method of the present invention, the parameters determined by using the mathematical tool tangent equation and the accurate mathematical model have high accuracy. The accurate mathematical model is simple and has fewer parameters, and also has stability, stability margin, and fast response characteristics in the time domain, so as to further improve and correct the accurate mathematical model. And based on the characteristics of the accurate mathematical model, control strategies such as time-delay Smith control, fuzzy control, neural network, adaptive control, and predictive control can be adopted to replace the original PID control of the equipment, effectively improving the stability, accuracy, and rapidity of material moisture control under specific production conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0102] Figure 1 FIG. is a flowchart of a method for experimentally obtaining a material moisture control model of a tobacco leaf conditioning machine provided in Embodiment 1 of the present invention;

[0103] Figure 2 FIG. is a schematic diagram of the conventional stage of moisture control of a tobacco leaf conditioning machine in a method for experimentally obtaining a material moisture control model of a tobacco leaf conditioning machine provided in Embodiment 1 of the present invention;

[0104] Figure 3 FIG. is a schematic diagram of the stable stage of moisture control of a tobacco leaf conditioning machine in a method for experimentally obtaining a material moisture control model of a tobacco leaf conditioning machine provided in Embodiment 1 of the present invention;

[0105] Figure 4 FIG. is a schematic diagram of an approximate single-loop process control in a method for experimentally obtaining a material moisture control model of a tobacco leaf conditioning machine provided in Embodiment 1 of the present invention;

[0106] Figure 5 FIG. is a schematic diagram of a step signal in a method for experimentally obtaining a material moisture control model of a tobacco leaf conditioning machine provided in Embodiment 1 of the present invention;

[0107] Figure 6It is a construction function in the method for experimentally obtaining the material moisture control model of the leaf conditioning machine provided in Embodiment 1 of the present invention Schematic diagram of the step response curve Detailed implementation manners

[0108] The technical solutions of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific features in the embodiments of the present application are detailed descriptions of the technical solutions of the present application, rather than limitations on the technical solutions of the present application. Without conflict, the technical features in the embodiments of the present application and the embodiments can be combined with each other

[0109] The term "and / or" in this article is merely a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this article generally represents an "or" relationship between the associated objects before and after

[0110] As Figures 1 to 6 shown, this embodiment provides a method for experimentally obtaining the material moisture control model of the leaf conditioning machine, including the following steps

[0111] Step 1: Enter the production stage when the leaf conditioning machine meets the production conditions

[0112] First, determine whether the loose leaf conditioning machine starts production. If so, proceed to the next step; otherwise, continue to wait until the production conditions are met. When the loose leaf conditioning machine meets the production conditions, enter the production stage

[0113] AStep 2: Perform moisture control on the leaf conditioning machine during the production stage, and define the stable stage of the moisture control of the leaf conditioning machine in a formulaic form

[0114] The inlet water addition control and the outlet water replenishment and addition control in the corresponding moisture control loop of the leaf conditioning machine are controlled by a single closed-loop negative feedback PID (Proportional Integral Derivative Controller). The hot air control, exhaust negative pressure control, and direct injection steam control that have an indirect impact on the outlet material moisture in the leaf conditioning machine are also controlled by a single closed-loop negative feedback PID. Define the set value SP in each PID control module as the preset set value (equipment parameter or recipe parameter) of each control loop in the production stage, as Figure 2 shown. The entire production process is carried out in a relatively stable feedback manner. When the outlet infrared moisture meter detects the material moisture value at the outlet, lock the outlet water replenishment and addition control that affects the outlet material moisture as the main material moisture control loop, cancel the preset set value of the outlet water replenishment and addition PID loop, and feedback the outlet material moisture value to the SP value of the outlet water replenishment and addition PID control loop through the PID cascade method for closed-loop control, as Figure 3 shown

[0115] The specific method is as follows: Add a new outlet material moisture # PID loop. The outlet material moisture value serves as the actual value PV6 of this PID, and the standard value of the outlet material moisture required by the process serves as the set value SP6 of this PID. The PID outputs a process value CV6 with a range of -100% to +100%, and then an adjust value is obtained through a simple conversion formula. The adjust value is the correction value calculated for each operation cycle and is used to correct the preset set value of the outlet water addition in real time to achieve the purpose of precise control.

[0116] The calculation formula for the adjust value is:

[0117] adjust = CV6 * K;

[0118] In the formula, K is the correction coefficient of the cascade PID. The adjust value is the correction value calculated for each operation cycle, and CV6 is the outlet material moisture # process value of the PID loop.

[0119] Add the adjust value to the preset set value of the outlet water addition to obtain the real-time set value of the outlet water addition and assign it to SP2. The real-time set value of the outlet water addition = adjust + the preset set value of the outlet water addition = CV6 * K + the preset set value of the outlet water addition.

[0120] Then, wait for the moisture control of the leaf conditioning machine to enter the stable stage. In this method, the definition of the stable stage of the moisture control of the leaf conditioning machine is: the inlet water addition control 1 # PID loop and the outlet water make-up and addition control 2 # PID loop in the corresponding outlet material moisture control loop of the leaf conditioning machine enter the moisture control stable state.

[0121] It should be noted that in this stage, define the thresholds TV1 to TV 17 , the thresholds TV1 to TV 17 are value range comparison type parameters used to judge whether the equipment enters the stable stage of the moisture control of the leaf conditioning machine respectively, and are set by the user according to debugging experience. Among them, the thresholds TV1, TV2, and TV5 correspond to the 1 # PID loop, the thresholds TV3, TV4, and TV6 correspond to the 2 # PID loop, the thresholds TV7, TV8, and TV 13 correspond to the 3 # PID loop, the thresholds TV9, TV 10 and TV 14 correspond to the 4 # PID loop, the thresholds TV 11 , TV 12 and TV15 Corresponding to 5 # PID loop, threshold value TV 16 and TV 17 Corresponding to the outlet moisture related value.

[0122] Define duration parameters time1~time 11 , duration parameters time1~time 11 are time length comparison type parameters respectively used to judge whether the equipment enters the stable stage of the moisture control of the tobacco conditioning machine, and are set by the user according to the debugging experience. Among them, time1 and time3 correspond to 1 # PID loop, time2 and time3 correspond to 2 # PID loop, time4 and time7 correspond to 3 # PID loop, time5 and time8 correspond to 4 # PID loop, time6 and time9 correspond to 5 # PID loop, time 10 and time 11 Corresponding to the outlet moisture related value.

[0123] Among them, the absolute value of the difference between the mean value of the set value SP1 minus the actual value PV1 of the inlet water addition control 1 within the time duration of time1 # PID loop is lower than the threshold value TV1, and the standard deviation value SD1 of the actual value PV1 within the time duration of time1 is lower than the threshold value TV2.

[0124] The outlet water replenishment and addition control 2 within the time duration of time2 # The absolute value of the difference between the mean value of the set value SP2 minus the actual value PV2 of the PID loop is lower than the threshold value TV3, and the standard deviation value SD2 of the actual value PV2 within the time duration of time2 is lower than the threshold value TV4.

[0125] The description based on the mathematical formula is:

[0126] For the inlet water addition control 1 # PID loop, within the time duration of time1:

[0127] ;

[0128] In the formula, is the mean value of the actual value PV1 of the inlet water addition amount in the stable stage of the moisture control of the tobacco conditioning machine, SP1 is the set value of the inlet water addition amount in the stable stage of the moisture control of the tobacco conditioning machine, and TV1 is the threshold value of the inlet water addition control 1 # PID loop;

[0129] The calculation formula is:

[0130] ;

[0131] In the formula, n1 is the number of actual values PV1 of the inlet water addition amount during the stable stage of the moisture control of the leaf conditioning machine, is the sum of the actual values PV1 of the inlet water addition amount during the stable stage of the moisture control of the leaf conditioning machine;

[0132] The calculation formula of SD1 is:

[0133] ;

[0134] In the formula, SD1 is the standard deviation of the actual value PV1 of the inlet water addition amount during the stable stage of the moisture control of the leaf conditioning machine, X i is the single sample value of the actual value PV1 of the inlet water addition amount during the stable stage of the moisture control of the leaf conditioning machine;

[0135] During the time with a duration of time1, ; TV2 is the threshold value of the inlet water addition control 1 # PID loop of the leaf conditioning machine;

[0136] For the outlet water replenishment and addition control 2 # PID loop, during the time with a duration of time2:

[0137] ;

[0138] In the formula, is the mean value of the actual value PV2 of the outlet water replenishment amount during the stable stage of the moisture control of the leaf conditioning machine, SP2 is the set value of the outlet water replenishment amount during the stable stage of the moisture control of the leaf conditioning machine, and TV3 is the threshold value of the outlet water replenishment and addition control 2 # PID loop of the leaf conditioning machine;

[0139] The calculation formula of is:

[0140] ;

[0141] In the formula, n2 is the number of actual values PV2 of the outlet water replenishment amount during the stable stage of the moisture control of the leaf conditioning machine, is the sum of the actual values PV2 of the outlet water replenishment amount during the stable stage of the moisture control of the leaf conditioning machine;

[0142] The calculation formula of SD2 is:

[0143] ;

[0144] In the formula, SD2 is the standard deviation of the actual value PV2 of the outlet makeup water volume during the stable stage of the moisture control of the leaf conditioning machine, and Y i is the single sample value of the actual value PV2 of the outlet makeup water volume during the stable stage of the moisture control of the leaf conditioning machine;

[0145] During the time with a duration of time2, ; TV4 is the threshold value of the outlet makeup water and water addition control 2 # of the PID loop during the stable stage of the moisture control of the leaf conditioning machine.

[0146] Meanwhile, the stable stage also needs to meet the following requirements: keep the inlet water addition control relatively stable and the outlet makeup water and water addition control relatively stable; keep the hot air control, exhaust negative pressure control, and direct injection steam control relatively stable.

[0147] The relatively stable inlet water addition control includes that the output value CV1 of the inlet water addition control 1 # of the PID loop remains lower than the threshold value TV5 and lasts for a corresponding period of time, and the relatively stable outlet makeup water and water addition control includes that the output value CV2 of the outlet makeup water and water addition control 2 # of the PID loop remains lower than the threshold value TV6 and lasts for a corresponding period of time.

[0148] The description based on mathematical formulas is:

[0149] , and the duration exceeds time3;

[0150] , and the duration exceeds time3;

[0151] In the formula, CV1 is the output value of the inlet water addition control 1 # of the PID loop during the stable stage of the moisture control of the leaf conditioning machine, CV2 is the output value of the outlet makeup water and water addition control 2 # of the PID loop during the stable stage of the moisture control of the leaf conditioning machine, TV5 is the threshold value of the inlet water addition control 1 # of the PID loop during the stable stage of the moisture control of the leaf conditioning machine, and TV6 is the threshold value of the outlet makeup water and water addition control 2 # of the PID loop.

[0152] In addition, the hot air control, exhaust negative pressure control, and direct injection steam control that have an indirect impact on the moisture of the outlet material in the leaf conditioning machine also need to meet the stable conditions, including: the 3#PID loop of the hot air temperature control circuit, the 4#PID loop of the exhaust negative pressure, and the 5#PID loop of the direct injection steam enter the moisture stable state.

[0153] Among them, the hot air temperature control 3 #The absolute value of the difference between the set value SP3 of the PID loop and the mean value of the actual value PV3 is lower than the threshold value TV7; the standard deviation value SD3 of the actual value PV3 within the duration of time4 is lower than the threshold value TV8; the exhaust negative pressure 4 within the duration of time5 # The absolute value of the difference between the set value SP4 of the PID loop and the mean value of the actual value PV4 is lower than the threshold value TV9; similarly, the standard deviation value SD4 of the actual value PV4 within the duration of time5 is lower than the threshold value TV 10 ; the direct injection steam 5 within the duration of time6 # The absolute value of the difference between the set value SP5 of the PID loop and the mean value of the actual value PV5 is lower than the threshold value TV 11 ; the standard deviation value SD5 of the actual value PV5 within the duration of time6 is lower than the threshold value TV 12 .

[0154] The description based on mathematical formula is:

[0155] For the hot air temperature control 3 # PID loop, within the duration of time4:

[0156] ;

[0157] In the formula, is the mean value of the actual value PV3 of the hot air temperature in the stable stage of the leaf moistening machine moisture control, SP3 is the set value of the hot air temperature in the stable stage of the leaf moistening machine moisture control, and TV7 is the threshold value of the hot air temperature control 3 # PID loop.

[0158] The calculation formula of is:

[0159] ;

[0160] In the formula, n3 is the number of the actual value PV3 of the hot air temperature in the stable stage of the leaf moistening machine moisture control, is the sum of the actual value PV3 of the hot air temperature in the stable stage of the leaf moistening machine moisture control;

[0161] The calculation formula of SD3 is:

[0162] ;

[0163] In the formula, SD3 is the standard deviation value of the actual value PV3 of the hot air temperature in the stable stage of the leaf moistening machine moisture control, W i is the single sample value of the actual value PV3 of the hot air temperature in the stable stage of the leaf moistening machine moisture control;

[0164] During the time period of time4 ; TV8 is the hot air temperature control 3 in the stable stage of the moisture control of the leaf conditioning machine # The threshold value of the PID loop;

[0165] For the exhaust negative pressure 4 # PID loop, during the time period of time5:

[0166] ;

[0167] In the formula, is the average value of the actual value PV4 of the exhaust negative pressure in the stable stage of the moisture control of the leaf conditioning machine, SP4 is the set value of the exhaust negative pressure in the stable stage of the moisture control of the leaf conditioning machine, and TV9 is the exhaust negative pressure 4 in the stable stage of the moisture control of the leaf conditioning machine # The threshold value of the PID loop;

[0168] The calculation formula of is:

[0169] ;

[0170] In the formula, n4 is the number of the actual values PV4 of the exhaust negative pressure in the stable stage of the moisture control of the leaf conditioning machine, is the sum of the actual values PV4 of the exhaust negative pressure in the stable stage of the moisture control of the leaf conditioning machine;

[0171] The calculation formula of SD4 is:

[0172] ;

[0173] In the formula, SD4 is the standard deviation of the actual value PV4 of the exhaust negative pressure in the stable stage of the moisture control of the leaf conditioning machine, Z i is the single sample value of the actual value PV4 of the exhaust negative pressure in the stable stage of the moisture control of the leaf conditioning machine;

[0174] During the time period of time5, ; TV 10 is the exhaust negative pressure 4 in the stable stage of the moisture control of the leaf conditioning machine # The threshold value of the PID loop;

[0175] For the direct injection steam 5 # PID loop, during the time period of time6:

[0176] ;

[0177] In the formula, is the mean value of the actual value PV5 of the direct injection steam in the stable stage of the moisture control of the leaf conditioning machine. SP5 is the set value of the direct injection steam in the stable stage of the moisture control of the leaf conditioning machine. TV 11 is the direct injection steam 5 in the stable stage of the moisture control of the leaf conditioning machine # is the threshold value of the PID loop;

[0178] The calculation formula is:

[0179] ;

[0180] In the formula, n5 is the number of actual values PV5 of the direct injection steam in the stable stage of the moisture control of the leaf conditioning machine, is the sum of the actual values PV5 of the direct injection steam in the stable stage of the moisture control of the leaf conditioning machine;

[0181] The calculation formula of SD5 is:

[0182] ;

[0183] In the formula, SD5 is the standard deviation of the actual value PV5 of the direct injection steam in the stable stage of the moisture control of the leaf conditioning machine, G i is the single sample value of the actual value PV5 of the direct injection steam in the stable stage of the moisture control of the leaf conditioning machine;

[0184] During the time with a duration of time6, , TV 12 is the direct injection steam 5 in the stable stage of the moisture control of the leaf conditioning machine # is the threshold value of the PID loop.

[0185] At the same time, the stable stage also needs to meet: keep the control of the hot air temperature control loop, the opening of the exhaust negative pressure valve and the control of the direct injection steam control loop relatively stable; keep the moisture of the material at the outlet of the leaf conditioning machine in a stable controlled state.

[0186] Hot air temperature control 3 # The output value CV3 of the PID loop remains lower than the threshold value TV 13 and lasts for a time of length time7, representing that the control of the hot air temperature control loop is relatively stable. Exhaust negative pressure 4 # The output value CV4 of the PID loop remains lower than the threshold value TV 14 and lasts for a time of length time8, representing that the opening of the exhaust negative pressure valve is relatively stable. Direct injection steam 5 # The output value CV of the PID loop remains lower than the threshold value TV 15 and lasts for a time of length time9, representing that the control of the direct injection steam control loop is relatively stable.

[0187] The description based on mathematical formulas is:

[0188] and the duration exceeds time7;

[0189] and the duration exceeds time8;

[0190] and the duration exceeds time9;

[0191] where CV3 is the hot air temperature control 3 # the output value of the PID loop, CV4 is the moisture exhaust negative pressure 4 # the output value of the PID loop, CV5 is the direct injection steam 5 # the output value of the PID loop, TV 13 is the hot air temperature control 3 # the threshold value of the PID loop, TV 14 is the moisture exhaust negative pressure 4 # the threshold value of the PID loop, TV 15 is the direct injection steam 5 # the threshold value of the PID loop.

[0192] In addition, the stable stage also needs to meet the following: the moisture content of the materials at the outlet of the leaf conditioner is in a stable and controlled state with small fluctuations. It is required that the absolute value of the difference between the actual value of the outlet material temperature and the controlled required value remains lower than the threshold value TV 16 and lasts for a corresponding period of time; the absolute value of the difference between the actual value of the outlet material moisture and the controlled required value remains lower than the threshold value TV 17 and lasts for a corresponding period of time.

[0193] The description based on mathematical formulas is:

[0194] and the duration exceeds time 10 ;

[0195] and the duration exceeds time 11 ;

[0196] where TV 16 and TV 17 are the moisture-related values corresponding to the outlet, is the actual value of the outlet material temperature, is the controlled required value of the outlet material temperature, is the actual value of the outlet material moisture, is the controlled required value of the outlet material moisture.

[0197] Only when all the above conditions and mathematical formulas are satisfied simultaneously can it be defined as the stable stage of the moisture control of the leaf conditioning machine.

[0198] Step 3: When the moisture control of the leaf conditioning machine enters the stable stage, approximate the non-linear time-varying system as a linearized time-invariant system to obtain the material moisture control model of the cigarette making leaf conditioning machine.

[0199] Only when entering the stable stage of the moisture control of the leaf conditioning machine can the non-linear time-varying system be approximated as a linearized time-invariant system, and only then can an accurate linearized control model in the stable stage of moisture control be obtained through complex methods, that is, the material moisture control model of the cigarette making leaf conditioning machine.

[0200] Since in the previous steps, the outlet water replenishment and addition control 2 # The PID loop is used as the only feedback control path for the outlet material moisture control, and the outlet material moisture value is fed back to the SP value of the outlet water replenishment and addition PID control loop in a PID cascade manner for closed-loop control. The speed of the water replenishment pump frequency controlled by the output of the outlet water replenishment and addition PID will directly control the level of the outlet material moisture. At this time, the outlet material moisture control of the entire leaf conditioning machine is simplified to a single process control, as shown in the box Figure 4 shown. Since the outlet water replenishment and addition control 2 # The change in the outlet material moisture controlled by the output of the PID loop of the outlet water replenishment and addition is non-oscillatory, monotonic, has hysteresis (time delay) and inertia, and has self-balancing ability, belonging to a self-regulating process. At the same time, based on considering the shape and characteristics of the step response curve of the outlet material moisture presenting the step response curve for the step characteristic curve of the water replenishment pump frequency output controlled by the outlet water replenishment and addition PID, this control process can be approximately modeled as a first-order lag model for accurate acquisition and accurate verification.

[0201] In the principle of automatic control, the transfer function of the first-order plus lag control model is:

[0202] ;

[0203] In the formula, K is the static amplification coefficient, Ts is the time constant, is the model lag time, s is the Laplace transform factor, is the transfer function of the material moisture control model of the cigarette making leaf conditioning machine.

[0204] After performing the inverse Laplace transform, under the action of the step disturbance quantity A, its time characteristic function is:

[0205] ;

[0206] In the formula, y(t) is the time characteristic function and t is the time.

[0207] The general shape of its function curve is asFigure 5 as shown

[0208] In the method of the present invention, a fixed increment value is given to the frequency value of the output make-up water pump by controlling the make-up water addition to the outlet, which is simulated into a stable step signal, and the moisture of the outlet material is recorded The data varying with time t are used, and a curve is fitted by using a computer algorithm. The K, T, three parameter values in the transfer function of the first-order plus lag control model are calculated in reverse through this curve, so as to obtain an approximate first-order lag model

[0209] The specific method is as follows: First, calculate the mean value of the frequency value of the output make-up water pump of the make-up water addition control PID loop at the outlet in the stable stage of the moisture control of the leaf conditioning machine , and its calculation formula is:

[0210] ;

[0211] In the formula, n6 is the number of data of the frequency value of the output make-up water pump of the make-up water addition control at the outlet in the stable stage of the moisture control of the leaf conditioning machine, is the sum of the actual values of the frequency value of the make-up water pump, is the mean value of the frequency value of the output make-up water pump of the make-up water addition control PID loop at the outlet in the stable stage of the moisture control of the leaf conditioning machine

[0212] Next, calculate the mean value of the moisture of the outlet material in the stable stage of the moisture control of the leaf conditioning machine , and its calculation formula is:

[0213] ;

[0214] In the formula, is the mean value of the moisture of the outlet material in the stable stage of the moisture control of the leaf conditioning machine, n7 is the number of data of the actual value of the moisture of the outlet material in the stable stage of the moisture control of the leaf conditioning machine, is the sum of the actual values of the moisture of the outlet material

[0215] If < (100% - P), then a given increment P is given and accumulated to the value, and the make-up water addition control 2 # PID loop is kept in the manual state, and the output CV2 value is always ( + P), simulating a step signal with a step amount of P, and always acting stably on the system output end, as Figure 5 shown. Record the data of the moisture of the outlet material varying with time t, and calculate and the mean value of the moisture of the outlet material in the stable stage of the moisture control of the leaf conditioning machine The difference, which is defined as the data y. The defining formula for y is:

[0216] ;

[0217] In the formula, y is the difference between the actual value of the moisture content of the outlet material in the stable stage of the leaf conditioning machine's moisture control and the average value of the moisture content of the outlet material in the stable stage of the moisture control. is the actual value of the moisture content of the outlet material in the stable stage of the leaf conditioning machine's moisture control.

[0218] According to the continuous action of the step signal, record the above y values, mark them on the coordinate with time t as the abscissa, and fit a curve. The general shape of the curve is as Figure 6 shown.

[0219] Use mathematical tools to calculate the three parameter values of K, T, in the transfer function of the first-order plus lag control model. The method is as follows:

[0220] First, define the value of K.

[0221] ;

[0222] In the formula, K is the static amplification coefficient. is the steady-state value of the step response curve, and A is the step disturbance increment value.

[0223] Then define a function , and let ;

[0224] Since the first-order lag model has self-balancing ability and belongs to a self-constant process. The step response must converge to a fixed value, which is defined as , and define the ratio of y(t) to as the function . Then the formula for the function is:

[0225] ;

[0226] In the formula, is the ratio of the time characteristic function y(t) to the steady-state value of the step response curve.

[0227] As Figure 6 shown, find a point D on the curve . The tangent slope value at this point is the largest. It can be deduced from the relevant knowledge of mathematical integration that the slope at the origin is zero, and as the t value increases, its slope gradually increases until it reaches point D where the slope is the maximum. After passing point D, as the t value increases, its slope gradually decreases and approaches When its slope approaches zero.

[0228] In the method of the present invention, since the recorded values of the automatic control system are sampling values at fixed time intervals, an algorithm for standardization is required to find the coordinate value of point D with higher accuracy and the tangent slope value passing through point D. The method is as follows:

[0229] Taking t = 0 as the starting point of data recording, and recording at intervals of Ts time each time values and storing them in the array A[a1, a2, a3,..., a n , where the array A contains n sampling data. Then subtract the previous value of the array A from the next value, and define it as the new array B[b1, b2, b3,..., b (n-1) , where b1 = a2 - a1, b2 = a3 - a2, b3 = a4 - a3,..., b (n-1) = a n - a (n-1) , and the array B contains n - 1 sampling data. Then divide each data of the array B to obtain the array C[c1, c2, c3,..., c (n-1) , where c1 = b1 / Ts, c2 = b2 / Ts, c3 = b3 / Ts,..., c (n-1) = b (n-1) / Ts, and the array C contains n - 1 sampling data.

[0230] Generally, set the length of Ts to be about 1 second. Therefore, directly find the largest data unit in the array C and define it as point D. Then the definition formula of the tangent slope kd at point D is:

[0231] ;

[0232] In the formula, the max() function is a commonly used function for finding the maximum value in statistics, and c d represents the largest data unit of the array C, and d is the serial number corresponding to the largest data unit of the array C, where 1 < d < (n - 1).

[0233] At the same time, the following continuous condition inequalities should also be satisfied:

[0234] ;

[0235] If the above continuous inequalities are not satisfied, it means that the model error is too large. It is necessary to re - formulate the conditions and parameters for the stable stage of the moisture control of the leaf conditioning machine and conduct a step - response test again until the maximum tangent slope point D of the accurate first - order lag transfer function and the above - mentioned continuous condition inequalities can be obtained.

[0236] The coordinates of point D are ; where, Ts*(d + 1) is the abscissa value of point D, representing the (d + 1)-th data in array A, is the ordinate value of point D, and the ordinate value is the corresponding value obtained by substituting the abscissa value into the function.

[0237] Thus, the expression of the tangent function g(x) passing through point D is:

[0238] ;

[0239] Substitute the coordinates of point B ( , 0) into the expression of g(x) to find , and obtain the formula:

[0240] ;

[0241] In the above equation, except for the value, all are known quantities, so the value can be calculated according to the above equation.

[0242] Substitute the coordinates of point A ( , 1) into the expression of g(x) to find T, and obtain the formula:

[0243] ;

[0244] Then the formula can be obtained:

[0245] ;

[0246] In the above equation, except for the T value, all are known quantities, so the T value can be calculated according to the above equation.

[0247] Thus, the transfer function of the material moisture control model of the silk reeling and leaf conditioning machine is:

[0248] ;

[0249] The values of parameter K, parameter T, and parameter have all been calculated. Thus, the material moisture control model of the silk reeling and leaf conditioning machine under the special production stable mode can be obtained.

[0250] It should be noted that when using this method for on-site tests and MATLAB simulations in Hangzhou Cigarette Factory, the effective parameter combinations are: TV1 = 1.0; TV2 = 0.3; TV3 = 0.3; TV4 = 0.2; TV5 = 5.0%; TV6 = 5.0%; TV7 = 3.0; TV8 = 0.3; TV9 = 0.5; TV 10 = 0.2; TV 11 = 0.9; TV 12 = 0.2; TV13 =TV 14 =TV 15 =5.0%; TV 16 =1; TV 17 =0.5; time1 = time2 = time3 = 200s; time4 = time5 = time6 = time7 = time8 = time9 = 150s; time 10 =time 11 =250s; A = 20%.

[0251] In summary, this embodiment provides a method for experimentally obtaining the material moisture control model of a leaf conditioning machine for cigarette making. It defines the stable stage of moisture control of the leaf conditioning machine in a formulaic form, effectively identifies the stage and application scenarios of a time-invariant system that can be approximated as linearized, and obtains an accurate mathematical model for the material moisture control of the leaf conditioning machine in the stable production stage. This model can be used when the production enters a stable state. By means of the method of cascading PID feedback to correct the outlet water supply set value, the moisture control of the tobacco leaf conditioning process materials can be effectively stabilized. In the form of connecting two single-feedback PIDs in series and combining the method of cumulative correction, the defined stable stage of moisture control of the leaf conditioning machine is closer to the actual situation, more effectively conforms to the processing characteristics of the tobacco cylinder device, has good feasibility, and can be carried out simultaneously with physical commissioning in the industry without wasting additional tobacco material resources. Compared with the traditional PID control, this method can approximate the properties and parameters of an accurate mathematical model. Based on the method of the present invention, the parameters determined by using the mathematical tool tangent equation and the accurate mathematical model have high accuracy. The accurate mathematical model is simple and has fewer parameters, and also has stability, stability margin, and fast response characteristics in the time domain, so as to further improve and correct the accurate mathematical model. And based on the characteristics of this accurate mathematical model, control strategies such as time-delay Smith control, fuzzy control, neural network, adaptive control, and predictive control can be adopted to replace the original PID control of the equipment, effectively improving the stability, accuracy, and rapidity of material moisture control under specific production conditions.

[0252] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the technical principle of the present invention, several improvements and deformations can still be made, and these improvements and deformations should also be regarded as the protection scope of the present invention.

Claims

1. A method for experimentally obtaining a material moisture control model of a silk reeling leaf moistening machine, characterized in that, Including: Enter the production stage when the leaf conditioning machine meets the production conditions; During the production stage, conduct moisture control on the leaf conditioning machine and define the stable stage of the moisture control of the leaf conditioning machine in a formulaic form; When the moisture control of the leaf conditioning machine enters the stable stage, approximate the non-linear time-varying system as a linearized constant system to obtain the material moisture control model of the cigarette making leaf conditioning machine; The defining formula for the stable stage of the moisture control of the leaf conditioning machine includes: For inlet water addition control 1 # The PID loop, within a duration of time1: ； In the formula, is the mean value PV1 of the actual water addition at the inlet during the stable stage of the moisture control of the leaf conditioning machine. SP1 is the set value of the water addition at the inlet during the stable stage of the moisture control of the leaf conditioning machine. TV1 is the inlet water addition control 1 during the stable stage of the moisture control of the leaf conditioning machine # The threshold of the PID loop; The calculation formula is as follows: ； Where n1 is the number of actual values PV1 of the inlet water addition amount in the stable stage of the moisture control of the leaf conditioning machine, is the sum of the actual values PV1 of the inlet water addition amount in the stable stage of the moisture control of the leaf conditioning machine; The calculation formula for SD1 is: ； Wherein, SD1 is the standard deviation of the actual value PV1 of the water addition amount at the inlet during the stable stage of the moisture control of the leaf conditioning machine, and X i is the single sample value of the actual value PV1 of the water addition amount at the inlet during the stable stage of the moisture control of the leaf conditioning machine; Within a time duration of time1, ; TV2 is the inlet water addition control 1 in the stable stage of moisture control for the leaf conditioning machine # The threshold of the PID loop; For export water replenishment and addition control 2 # The PID loop, within a duration of time2: ； Wherein, is the mean value PV2 of the actual water replenishment amount at the outlet during the stable stage of the moisture control of the leaf conditioning machine, SP2 is the set value of the water replenishment amount at the outlet during the stable stage of the moisture control of the leaf conditioning machine, and TV3 is the outlet water replenishment and water addition control 2 during the stable stage of the moisture control of the leaf conditioning machine # The threshold value of the PID loop; The calculation formula is as follows: ； In the formula, n2 is the number of actual values PV2 of the outlet makeup water volume in the stable stage of the moisture control of the leaf conditioning machine, and is the sum of the actual values PV2 of the outlet makeup water volume in the stable stage of the moisture control of the leaf conditioning machine; The calculation formula for SD2 is: ； Wherein, SD2 is the standard deviation of the actual value PV2 of the outlet makeup water volume in the stable stage of the moisture control of the leaf conditioning machine, and Y i is the single sample value of the actual value PV2 of the outlet makeup water volume in the stable stage of the moisture control of the leaf conditioning machine; Within the time duration of time2 ; TV4 is the outlet water replenishment and addition control 2 during the stable stage of the moisture control of the leaf conditioning machine # The threshold value of the PID loop 2. The method for obtaining the material moisture control model of the silk-making leaf-conditioning machine according to claim 1, characterized in that The moisture control of the leaf conditioning machine during the production stage includes: Adopt a PID control module to control the inlet water addition control, outlet water replenishment and addition control, hot air control, exhaust negative pressure control, and direct injection steam control in the moisture control loop of the leaf conditioning machine; Define the set value SP in the PID control module as the preset set value of the moisture control loop during the production stage, and the preset set value includes equipment parameters and / or formula parameters.

3. The method for obtaining the material moisture control model of the leaf conditioning machine in the test according to claim 2, wherein The moisture control of the leaf conditioning machine during the production stage further includes: When the outlet infrared moisture meter detects the material moisture value at the outlet, take the outlet water replenishment and addition control as the main material moisture control loop; the outlet water replenishment and addition control is used to control the outlet material moisture; Cancel the preset set value of the outlet water replenishment and addition control loop, and feedback the material moisture value at the outlet to the set value SP of the outlet water replenishment and addition PID control loop in a PID cascade manner for closed-loop control.

4. The method for obtaining the material moisture control model of the leaf conditioning machine in the test according to claim 3, characterized in that The definition of the stable stage of the moisture control of the leaf conditioning machine includes: Inlet water addition control 1 in the corresponding outlet material moisture control loop of the leaf conditioning machine # PID loop and outlet make-up water and water addition control 2 # The PID loop enters the moisture control stable state; Among them, the inlet water addition control 1 within the time period with a duration of time1 # The absolute value of the difference between the set value SP1 of the PID loop and the mean value of the actual value PV1 is lower than the threshold value TV1, and the standard deviation value SD1 of the actual value PV1 within the time period with a duration of time1 is lower than the threshold value TV2; Outlet make-up water addition control 2 within the time period with a duration of time2 # The absolute value of the difference between the setpoint SP2 of the PID loop and the mean of the actual value PV2 is lower than the threshold TV3, and the standard deviation SD2 of the actual value PV2 within the time period with a duration of time2 is lower than the threshold TV4.

5. The method for obtaining the material moisture control model of the silk reeling and leaf conditioning machine according to claim 4, characterized in that, The definition of the stable stage of the moisture control of the leaf conditioning machine further includes: Keep the inlet water addition control relatively stable and the outlet water replenishment and addition control relatively stable; keep the hot air control, exhaust negative pressure control, and direct injection steam control relatively stable; The inlet water addition control is relatively stable, including inlet water addition control 1 # The output value CV1 of the PID loop remains lower than the threshold value TV5. The outlet water replenishment and addition control is relatively stable, including outlet water replenishment and addition control 2 # The output value CV2 of the PID loop remains lower than the threshold value TV6; The relative stability of the maintained hot air control, moisture exhaust negative pressure control, and direct injection steam control includes the hot air temperature control loop 3 # PID loop, moisture exhaust negative pressure 4 # PID loop, and direct injection steam 5 # PID loop enters the moisture stable state; Among them, the hot air temperature control 3 within the duration of time4 # The absolute value of the difference between the set value SP3 of the PID loop and the mean value of the actual value PV3 is lower than the threshold value TV7; the standard deviation value SD3 of the actual value PV3 within the duration of time4 is lower than the threshold value TV8; the exhaust negative pressure 4 within the duration of time5 # The absolute value of the difference between the set value SP4 of the PID loop and the mean value of the actual value PV4 is lower than the threshold value TV9; the standard deviation value SD4 of the actual value PV4 within the duration of time5 is lower than the threshold value TV 10 ; the direct injection steam 5 within the duration of time6 # The absolute value of the difference between the set value SP5 of the PID loop and the mean value of the actual value PV5 is lower than the threshold value TV 11 ; the standard deviation value SD5 of the actual value PV5 within the duration of time6 is lower than the threshold value TV 12 .

6. The method for obtaining the material moisture control model of the silk reeling and leaf conditioning machine according to claim 5, characterized in that The defining formula for the stable stage of the moisture control of the leaf conditioning machine further includes: and the duration exceeds time3; and the duration exceeds time3; Wherein, CV1 is the inlet water addition control 1 during the stable stage of the moisture control of the leaf conditioning machine # Output value of the PID loop, CV2 is the outlet water replenishment and addition control 2 during the stable stage of the moisture control of the leaf conditioning machine # Output value of the PID loop, TV5 is the inlet water addition control 1 during the stable stage of the moisture control of the leaf conditioning machine # Threshold value of the PID loop, TV6 is the outlet water replenishment and addition control 2 during the stable stage of the moisture control of the leaf conditioning machine # Threshold value of the PID loop; For hot air temperature control 3 # The PID loop, within a duration of time4: ； In the formula, is the mean value of the actual value PV3 of the hot air temperature in the stable stage of the moisture control of the leaf conditioning machine. SP3 is the set value of the hot air temperature in the stable stage of the moisture control of the leaf conditioning machine. TV7 is the hot air temperature control 3 in the stable stage of the moisture control of the leaf conditioning machine # The threshold value of the PID loop; The calculation formula is as follows: ； Where n3 is the number of actual values PV3 of the hot air temperature in the stable stage of the moisture control of the leaf conditioning machine, and is the sum of the actual values PV3 of the hot air temperature in the stable stage of the moisture control of the leaf conditioning machine; The calculation formula for SD3 is: ； Wherein, SD3 is the standard deviation of the actual value PV3 of the hot air temperature in the stable stage of the moisture control of the leaf conditioning machine, and W i is the single sample value of the actual value PV3 of the hot air temperature in the stable stage of the moisture control of the leaf conditioning machine; During the time period with a duration of time4, ; TV8 is the hot air temperature control 3 in the stable stage of the moisture control of the leaf conditioning machine # The threshold value of the PID loop; For the exhaust negative pressure 4 # The PID loop, within the time duration of time5: ； Wherein, is the mean value PV4 of the actual value of the exhaust negative pressure in the stable stage of the moisture control of the leaf conditioning machine, SP4 is the set value of the exhaust negative pressure in the stable stage of the moisture control of the leaf conditioning machine, and TV9 is the exhaust negative pressure 4 in the stable stage of the moisture control of the leaf conditioning machine # The threshold value of the PID loop; The calculation formula is as follows: ； In the formula, n4 is the number of actual values PV4 of the exhaust negative pressure in the stable stage of the moisture control of the leaf conditioning machine, and is the sum of the actual values PV4 of the exhaust negative pressure in the stable stage of the moisture control of the leaf conditioning machine; The calculation formula for SD4 is: ； Wherein, SD4 is the standard deviation of the actual value PV4 of the exhaust negative pressure in the stable stage of the moisture control of the leaf conditioning machine, and Z i is the single sample value of the actual value PV4 of the exhaust negative pressure in the stable stage of the moisture control of the leaf conditioning machine; Within a time duration of time5, ; TV 10 is the exhaust negative pressure 4 during the stable stage of moisture control of the leaf conditioning machine # the threshold of the PID loop; For direct injection steam 5 # PID loop, within a duration of time6: ； In the formula, is the mean value PV5 of the actual value of the direct injection steam in the stable stage of the moisture control of the leaf conditioning machine, SP5 is the set value of the direct injection steam in the stable stage of the moisture control of the leaf conditioning machine, and TV 11 is the direct injection steam 5 # in the PID loop threshold value; The calculation formula is as follows: ； Where n5 is the number of actual values PV5 of the direct injection steam in the stable stage of the moisture control of the leaf conditioning machine, and is the sum of the actual values PV5 of the direct injection steam in the stable stage of the moisture control of the leaf conditioning machine; The calculation formula for SD5 is: ； Wherein, SD5 is the standard deviation of the actual value PV5 of the direct injection steam in the stable stage of the moisture control of the leaf conditioning machine, and G i is the single sample value of the actual value PV5 of the direct injection steam in the stable stage of the moisture control of the leaf conditioning machine; During the time with a duration of time6, , TV 12 is the direct injection steam 5 in the stable stage of the moisture control of the leaf moistening machine # Threshold value of the PID loop.

7. The method for obtaining the material moisture control model of the leaf conditioning machine for cigarette making according to claim 6, wherein The definition of the stable stage of the moisture control of the leaf conditioning machine further includes: Keep the hot air temperature control loop control, the opening of the exhaust negative pressure valve, and the direct injection steam control loop control relatively stable; keep the moisture of the material at the outlet of the leaf conditioning machine in a stable controlled state; The hot air temperature control loop is relatively stable in control, including hot air temperature control 3 # The output value CV3 of the PID loop remains below the threshold value TV 13 and lasts for a time period of length time7; The opening of the exhaust negative pressure valve is relatively stable, including the exhaust negative pressure 4 # The output value CV4 of the PID loop remains lower than the threshold value TV 14 and lasts for a time period of time8; The direct injection steam control loop controls relatively stably and includes direct injection steam 5 # The output value CV5 of the PID loop remains below the threshold value TV 15 and lasts for a time period of length time9; The moisture content of the material at the outlet of the leaf conditioning machine being in a stable and controlled state includes the actual value of the temperature of the material at the outlet and the absolute value of the difference from the controlled required value is kept lower than the threshold value TV 16 ; the absolute value of the difference between the actual value of the moisture content of the material at the outlet and the controlled required value is kept lower than the threshold value TV 17 .

8. The method for obtaining the material moisture control model of the silk reeling and leaf conditioning machine according to claim 7, characterized in that, The defining formula for the stable stage of the moisture control of the leaf conditioning machine further includes: and the duration exceeds time7; and the duration exceeds time8; and the duration exceeds time9; and the duration exceeds time 10 ; and the duration exceeds time 11 ; Wherein, CV3 is the hot air temperature control 3 # Output value of the PID loop, CV4 is the moisture exhaust negative pressure 4 # Output value of the PID loop, CV5 is the direct injection steam 5 # Output value of the PID loop, TV 13 Is the hot air temperature control 3 # Threshold value of the PID loop, TV 14 Is the moisture exhaust negative pressure 4 # Threshold value of the PID loop, TV 15 Is the direct injection steam 5 # Threshold value of the PID loop, TV 16 And TV 17 Is the moisture-related value corresponding to the outlet, Is the actual value of the outlet material temperature, Is the controlled required value of the outlet material temperature, Is the actual value of the outlet material moisture, Is the controlled required value of the outlet material moisture.

9. The method for obtaining the material moisture control model of the silk reeling and leaf moistening machine according to claim 8, characterized in that The method for obtaining the material moisture control model of the cigarette making leaf conditioning machine includes: Give a fixed increment value to the frequency value of the make-up water pump output by the outlet water replenishment and addition control and simulate it as a stable step signal; Record the data of the actual value of the outlet material moisture changing with time t and fit it into a curve using a computer algorithm; Reverse calculate the parameter values in the transfer function of the first-order plus lag control model through the curve to obtain an approximate first-order lag model, and the approximate first-order lag model is the material moisture control model of the cigarette making leaf conditioning machine; The material moisture control model of the cigarette making leaf conditioning machine is: ； where K is the static amplification factor, Ts is the time constant, is the model lag time, s is the Laplace transform factor, is the transfer function of the material moisture control model of the silk reeling and leaf conditioning machine.

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