Control method of drying system and drying system

Abstract

The invention provides a control method of a drying system and the drying system. The control method comprises the following steps: monitoring state information reflecting tobacco drying quality; according to the actual index value and the factor priority of each state factor in the state information in the current drying stage, determining the state factor which has the greatest influence on the quality of the current drying stage; and the drying parameters are adjusted, so that the state factor which has the maximum influence on the quality of the current drying stage returns to the reasonable deviation range. By reflecting the state information of the tobacco drying quality, the unit drying operation parameters are adjusted, the deviation of the state factor is pulled back to the normal preset range, and the consistency of the drying quality is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of drying, and in particular to a control method of a drying system and a drying system. Background Art

[0002] Tobacco drying, also known as tobacco baking or tobacco leaf baking, is an indispensable and important part of tobacco processing. The process aims to properly dry the freshly harvested tobacco leaves to achieve the ideal moisture content, while promoting the complex transformation of the internal chemical composition, thereby giving the tobacco leaves a unique color, rich aroma and good combustion performance. This process usually includes several key stages, such as preheating, drying, color fixing and cooling. The design and execution of specific steps are often adjusted due to differences in tobacco varieties (such as sun-cured tobacco, air-cured tobacco, and flue-cured tobacco) and baking processes. The sophistication of the process directly affects the quality and market competitiveness of the final product.

[0003] Traditional tobacco drying methods mostly rely on manual monitoring and basic temperature and humidity control equipment, which is not only highly dependent on the operator's experience, but also has problems of low efficiency and high energy consumption. Moreover, such methods are difficult to ensure the consistency of tobacco leaf baking quality in actual production, and are prone to insufficient or over-drying, which in turn affects the flavor and economic value of the tobacco leaves. Summary of the invention

[0004] In order to solve the technical problem that it is difficult to ensure the quality consistency of tobacco leaf baking by manual monitoring in the above-mentioned prior art, the present invention provides a control method of a drying system and a drying system.

[0005] The technical solution adopted by the present invention is:

[0006] The present invention proposes a control method for a drying system, comprising the steps of:

[0007] Monitor status information reflecting tobacco drying quality;

[0008] Determine the state factor that has the greatest impact on the quality of the current drying stage according to the actual index value of each state factor in the current drying stage and the priority of the factor in the state information;

[0009] Adjust the drying parameters so that the state factor that has the greatest impact on the quality of the current drying stage returns to a reasonable deviation range.

[0010] Specifically, according to the actual index value of each state factor in the current drying stage and the priority of the factor in the state information, the state factor having the greatest impact on the quality of the current drying stage is determined to include:

[0011] Calculate the deviation rate of each state factor relative to the actual index value of the current drying stage. When there are multiple state factors with deviation rates exceeding the preset deviation range, determine the state factor with the greatest impact on the quality of the current drying stage based on the weight ratio of each state factor in the current drying stage.

[0012] Specifically, according to the actual index value of each state factor in the current drying stage and the priority of the factor in the state information, the state factor having the greatest impact on the quality of the current drying stage is determined to include:

[0013] The deviation rate of each state factor relative to the actual index value of the current drying stage is calculated. When there is only one state factor whose deviation rate exceeds the preset deviation range, the state factor is determined to be the state factor with the greatest impact on the quality of the current drying stage.

[0014] Furthermore, calculating the deviation rate of each state factor relative to the actual index value of the current drying stage specifically includes:

[0015] An actual process curve is generated by acquiring the actual value and time value of the detected state factor and comparing it with the corresponding index process curve. The state factor offset rate is obtained by subtracting the target value in the index process curve from the actual value in the actual process curve and dividing it by the target value.

[0016] Specifically, the status factors included in the status information are: moisture content, color factor and texture factor.

[0017] When the moisture content is the state factor that has the greatest impact on the quality of the current drying stage, the drying parameters to be adjusted are specifically:

[0018] Determine whether the deviation rate of the moisture content deviates from the upper limit value of the preset deviation range;

[0019] If yes, lower the drying temperature and shorten the drying time; if no, extend the drying time.

[0020] The state factor that has the greatest impact on the quality of the current drying stage is specifically:

[0021] Determine whether the deviation rate of the color factor deviates from the upper limit value of the preset deviation range;

[0022] If yes, lower the drying temperature and shorten the drying time; if no, increase the drying temperature and drying humidity and extend the drying time.

[0023] When the texture factor is the state factor that has the greatest impact on the quality of the current drying stage, the adjustment of the drying parameters specifically includes:

[0024] If the texture factor is in the rising stage of its corresponding index process curve, determine whether the deviation rate of the texture factor deviates from the upper limit of the preset deviation range; if so, reduce the drying temperature, reduce the drying humidity, and shorten the drying time; if not, increase the drying temperature, increase the drying humidity, and extend the drying time;

[0025] If the texture factor is in the downward rising stage of its corresponding indicator process curve, determine whether the deviation rate of the color factor deviates from the upper limit value of the preset deviation range; if so, increase the drying temperature and extend the drying time; if not, reduce the drying temperature and drying humidity, and shorten the drying time.

[0026] Specifically, the drying stage includes: a preheating stage, a color fixing stage and a drying stage; each stage is divided into multiple sub-stages according to demand, and the weight ratio of each state factor in each sub-stage is different.

[0027] Furthermore, the drying parameters included in each of the drying sub-stages are: target drying temperature Tn, target drying humidity Wn; and each of the drying sub-stages is divided in turn into: an adjustment section for achieving the target drying temperature Tn and target drying humidity Wn of this stage, and a stabilization section in which the drying parameter adjustment step can be executed.

[0028] The weights of the various state factors in the preheating stage are moisture content, color factor and texture factor from high to low;

[0029] The weights of the various state factors in the color fixing stage are color factor, texture factor, and moisture content from high to low;

[0030] The weights of the various state factors in the drying stage are moisture content, texture factor, and color factor from high to low.

[0031] The present invention also provides a drying system, which uses the above control method to adjust the drying parameters of each drying stage.

[0032] The drying system includes: a weighing sensor for weighing the weight of tobacco leaves, an image sensor for taking images of the surface of tobacco leaves, and a heat pump dryer for drying the tobacco leaves; a controller for calculating the moisture content of the tobacco leaves based on the weight parameters detected by the weighing sensor and the image information detected by the image sensor, and evaluating the color and texture factors of the tobacco leaves, and controlling the heat pump dryer based on the information obtained.

[0033] Compared with the prior art, the present invention has the following advantages:

[0034] The present invention monitors the drying status information and determines the key influencing factors, specifically the moisture content and color factors related to tobacco quality, to reduce the quality inconsistency problem caused by insufficient manual monitoring in the traditional drying process, and dynamically adjusts the drying parameters based on the priority of each status factor to ensure the stability of the drying effect and the consistency of product quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0036] Figure 1 is a flow chart of an embodiment of the present invention;

[0037] Figure 2 is a control flow chart in a specific embodiment of the present invention;

[0038] Figure 3 It is a control flow chart according to texture factors in a specific embodiment of the present invention. DETAILED DESCRIPTION

[0039] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0040] The principle and structure of the present invention are described in detail below with reference to the accompanying drawings and embodiments.

[0041] Traditional tobacco drying methods mostly rely on manual monitoring and basic temperature and humidity control equipment. This method is not only highly dependent on the operator's experience, but also has problems of low efficiency and high energy consumption. More importantly, this type of method is difficult to ensure the consistency of tobacco leaf baking quality in actual production, and is prone to insufficient or over-drying, which in turn affects the flavor and economic value of the tobacco leaves. At the same time, faced with different climatic conditions and various tobacco varieties, traditional processes have poor adaptability and lack the ability to flexibly respond to complex environmental conditions. These problems have become bottlenecks restricting the development of the industry, and technical improvements are urgently needed to improve the overall process level and production efficiency.

[0042] In this regard, Figure 1 As shown, the present invention proposes a control method for a drying system, comprising:

[0043] Monitor the status information reflecting the tobacco drying quality; for example, collect key parameter data related to the tobacco drying process through sensors, including but not limited to temperature, humidity, tobacco leaf images and moisture content of tobacco leaves, so as to obtain the changes of various status information in the drying process in real time;

[0044] According to the actual index value and factor priority of each state factor in the current drying stage in the state information, determine the state factor that has the greatest impact on the quality of the current drying stage; compare the collected state information with the preset drying stage target value, and identify the specific impact of each state factor on the quality in combination with the process requirements of the current stage. According to the importance of the influencing factors, focus on analyzing the key factors with large deviations, and use this to determine the state factors that have the greatest impact on the tobacco drying quality, so as to facilitate subsequent adjustments;

[0045] Adjust the drying parameters to make the state factors that have the greatest impact on the quality of the current drying stage return to a reasonable deviation range. Based on the determined key state factors, by adjusting the corresponding drying parameters (such as the power of the heating equipment, the degree of opening of the humidity control valve and the duration, etc.), gradually reduce the deviation of the key factors and ensure that they return to the target range.

[0046] The present invention can improve drying efficiency and accuracy by monitoring drying status information and determining factors affecting tobacco drying quality, and reduce the quality inconsistency problem caused by insufficient manual monitoring in the traditional drying process. At the same time, the drying parameters are dynamically adjusted based on the priority of each status factor to ensure the stability of the drying effect and the consistency of product quality.

[0047] like Figure 2 As shown, in a specific embodiment, according to the actual index value of each state factor in the current drying stage and the priority of the factor in the state information, the state factor having the greatest impact on the quality of the current drying stage is determined to specifically include:

[0048] Calculate the deviation rate of each state factor relative to the actual index value of the current drying stage; specifically, each state factor has a corresponding index process curve, the X-axis of the index process curve is time, and the Y-axis is the target value of the state factor, and by obtaining the actual process curve of the state factor, the X-axis of the actual process curve is the detection time, and the Y-axis is the actual value of the state factor; by comparing the actual value of the collected state factor with the target value, the deviation rate can be used to quantitatively evaluate the degree of deviation of each state factor, and the deviation rate is specifically the absolute value of the actual index value minus the target value;

[0049] When there are multiple status factors whose deviation rates exceed the preset deviation range, the status factor with the greatest impact on the quality of the current drying stage is determined according to the weight ratio of each status factor in the current drying stage; for example, the multiple factors exceeding the deviation range can be prioritized based on the process importance weight of each status factor in the current stage; the key factor with the greatest impact on the quality is determined by calculating the comprehensive impact index of each status factor, so as to perform precise drying adjustments to avoid misadjustments or erroneous adjustments.

[0050] By quantitatively calculating the deviation rate and combining it with weight analysis, we can effectively avoid the adjustment errors that may be caused by relying solely on experience and judgment. Multi-factor priority sorting can ensure that key influencing factors are accurately identified, which is suitable for complex process scenarios and can greatly improve control efficiency while ensuring drying quality.

[0051] Further, when there is only one state factor whose deviation rate exceeds the preset deviation range, this state factor is determined to be the state factor having the greatest impact on the quality of the current drying stage.

[0052] That is, if there is only one state factor whose deviation rate exceeds the preset deviation range, it means that the other state factors are within a reasonable range. At this time, the drying parameters associated with the state factor can be directly adjusted.

[0053] In the above steps, calculating the deviation rate of each state factor relative to the actual index value of the current drying stage specifically includes:

[0054] The actual process curve is generated by acquiring the actual value and time value of the detected state factors; the data acquisition system of the sensor and the controller is used to record the changes of each state factor in real time, specifically using time as the horizontal axis and the actual value of the state factor as the vertical axis, to generate an actual process curve reflecting the dynamic changes of the drying process, thereby intuitively displaying the change trend of the state factor;

[0055] Compare the actual process curve with the corresponding index process curve; according to the preset process requirements, set an ideal index process curve for each state factor. The relationship between the target value and time in the curve reflects the process goals of each stage. By comparing the actual process curve with the index process curve, it is possible to intuitively determine whether the actual operation of the state factor deviates from the expected goal.

[0056] The real-time detection value of the actual process curve and the target value of the index process curve are calculated to obtain the difference between the two. The difference is divided by the target value and the result is taken as the deviation rate. The deviation rate can accurately reflect the degree of deviation of each state factor in the current drying stage.

[0057] That is, through the dynamic comparison between the actual process curve and the index process curve, not only can the deviation of each state factor be determined, but also the potential quality problems in the drying process can be monitored in real time. It has good versatility and is suitable for the analysis of different drying stages and multiple state factors.

[0058] In a specific embodiment, the state factors included in the state information are specifically: moisture content, color factor and texture factor. These state factors can respectively reflect the quality characteristics of tobacco leaves in different dimensions during the drying process, among which the moisture content determines the dryness of tobacco leaves, the color factor affects the appearance quality, and the texture factor determines the flexibility and processing adaptability of tobacco leaves.

[0059] Specifically, when the moisture content is the state factor that has the greatest impact on the quality of the current drying stage, the drying parameters to be adjusted are:

[0060] Determine whether the deviation rate of the moisture content deviates from the upper limit value of the preset deviation range;

[0061] If the moisture content deviation rate deviates from the upper limit, shorten the drying time and lower the drying temperature to slow down the drying speed and avoid excessive water loss;

[0062] If the deviation rate of the moisture content does not deviate from the upper limit value, the drying time is extended to further promote water evaporation and ensure the drying effect.

[0063] It should be noted that the indicator process curve corresponding to the moisture content in each drying stage gradually decreases, so the corresponding correction control method of the moisture content deviation rate in each stage is the same.

[0064] Specifically, when the color factor is the state factor that has the greatest impact on the quality of the current drying stage, the drying parameters are adjusted as follows:

[0065] It is possible to determine whether the deviation rate of the color factor deviates from the upper limit of the preset deviation range, and specifically monitor the color change of tobacco leaves through image acquisition and analysis technology;

[0066] If the deviation rate of the color factor deviates from the upper limit, reduce the drying temperature and shorten the drying time to reduce the darkening or uneven color caused by high temperature and high humidity;

[0067] If the deviation rate of the color factor does not deviate from the upper limit value, the drying temperature and humidity should be increased, and the drying time should be extended to accelerate the color transformation of the tobacco leaves and improve the appearance quality.

[0068] It should be noted that during the three-stage drying process, the color changes of tobacco leaves are roughly as follows:

[0069] Preheating stage: green → light yellow or yellow-green;

[0070] Color fixing stage: light yellow or yellow-green → golden yellow or dark yellow;

[0071] Drying stage: golden yellow or dark yellow → stable golden yellow or brown yellow;

[0072] Color quantization has the following changes: the actual value of the color factor will become larger and larger according to the comprehensive quantification of the colorimetric parameters red, green, yellow and blue until it stabilizes; that is, the corresponding indicator process curve gradually increases, so the corresponding correction control method of the deviation rate of the color factor in each stage is the same.

[0073] like Figure 3 As shown in FIG. 1 , when the texture factor is the state factor that has the greatest impact on the quality of the current drying stage, the adjustment drying parameters are specifically:

[0074] If the texture factor is in the rising stage of its corresponding index process curve, determine whether the deviation rate of the texture factor deviates from the upper limit value of the preset deviation range;

[0075] If the deviation rate of the texture factor deviates from the upper limit, reduce the drying temperature, reduce the drying humidity, and shorten the drying time to improve the softness of the internal fibers of the tobacco leaves;

[0076] If the deviation rate of the texture factor does not deviate from the upper limit value, increase the drying humidity and extend the drying time to enhance the firmness and uniformity of the texture.

[0077] If the texture factor is in the downward rising stage of its corresponding indicator process curve, determine whether the deviation rate of the color factor deviates from the upper limit value of the preset deviation range; if so, increase the drying temperature and extend the drying time; if not, reduce the drying temperature and drying humidity, and shorten the drying time.

[0078] During the three-stage drying process, the softness of the tobacco, that is, the texture factor, will increase in the preheating stage, increase first and then decrease in the color fixing stage, and further decrease in the drying stage, eventually becoming drier and more brittle. Therefore, the deviation of the texture factor will be adjusted differently according to the different stages.

[0079] The above method dynamically adjusts the drying parameters according to the deviation of different state factors, which can solve the quality problems in the drying process in a targeted manner and ensure that key indicators such as moisture content, color and texture are always kept within a reasonable range. By refining the adjustment logic, the intelligent level of the drying system is further improved, and the control accuracy is improved. At the same time, it can effectively reduce human intervention, improve production efficiency, and ensure the stability and consistency of product quality.

[0080] Specifically, the drying stage includes: a preheating stage, a color fixing stage and a drying stage; each stage is divided into multiple sub-stages according to demand, and the weight ratio of each state factor in each sub-stage is different.

[0081] In the preheating stage, the temperature is gradually raised to promote uniform distribution of moisture in the tobacco leaves, while avoiding the phenomenon that the surface of the tobacco leaves is dried quickly while the inner layer is moist due to sudden high temperature. This stage focuses on the moisture content status factor, which has a relatively high weight, while the color factor and texture factor have a relatively low weight, to ensure the initial regulation of moisture. According to demand, the preheating stage can be divided into multiple sub-stages, such as the low temperature adaptation stage and the temperature rise balance stage, and the status factors are dynamically monitored and adjusted in each sub-stage.

[0082] In the color fixing stage, the temperature is gradually increased and the humidity is controlled to make the chemical components in the tobacco leaves react, giving the tobacco leaves the ideal color and aroma. In this stage, the color factor occupies a dominant position, with the highest weight, while the weight of moisture content and texture factors is relatively reduced. According to demand, the color fixing stage can be further divided into sub-stages such as preliminary coloring, color stabilization and optimization adjustment, and the parameters are finely controlled to ensure the uniformity and stability of the tobacco leaf color.

[0083] In the drying stage, the moisture is evaporated efficiently to make the tobacco leaves reach the appropriate moisture content, while the texture is optimized to adapt to subsequent processing. In this stage, the weight of moisture content and texture factors is relatively balanced, while the weight of color factors is the smallest. The drying stage is usually divided into a rapid evaporation stage and a stable finishing stage. Each sub-stage adjusts parameters according to the target to achieve the coordinated development of moisture evaporation and texture optimization.

[0084] By reasonably dividing the drying stages and their sub-stages, and setting differentiated weights for the priorities of the state factors in different stages, the drying efficiency and quality consistency can be maximized. By dynamically adjusting the control strategies of each stage and sub-stage, it can accurately meet different process requirements and avoid quality deviations caused by a single control mode. It can be applied to drying tasks under various tobacco types and complex environmental conditions.

[0085] Specifically, the drying parameters included in each drying sub-stage are: target drying temperature Tn, target drying humidity Wn; and each drying sub-stage is divided into an adjustment stage and a stabilization stage in sequence.

[0086] The drying parameters included in the adjustment stage are temperature adjustment time Hc1 and humidity adjustment time Hw1. The temperature adjustment time Hc1 is used to gradually reach the target drying temperature Tn set in the sub-stage to avoid excessive drying of the tobacco surface or internal moisture retention due to rapid temperature rise. The humidity adjustment time Hw1 is used to control the humidity of the drying environment to ensure that the tobacco leaves maintain an appropriate evaporation rate during the heating process to avoid adverse effects on quality caused by excessive or low humidity.

[0087] It should be noted that the method of the present invention mainly adjusts the drying parameters in the stable section. The drying parameters included in the stable section include the temperature stabilization time Hc2 and the humidity stabilization time Hw2, and the target drying temperature Tn and the target drying humidity Wn can be adjusted in the stable section, wherein the aforementioned extension or shortening of the drying time mainly extends or shortens the temperature stabilization time Hc2 and the humidity stabilization time Hw2 (the temperature stabilization time Hc2 and the humidity stabilization time Hw2 are both extended or shortened simultaneously). According to the state factor deviation of the current stage, the target temperature and target humidity are adjusted to achieve dynamic correction of the target parameters, and by controlling the duration of temperature and humidity, the state factor that has the greatest impact on the quality of the current drying stage is returned to a reasonable deviation range.

[0088] By setting a stable section and an adjusting section, in the adjusting section, the target drying temperature and humidity are quickly reached mainly through the original adjusting method of the drying system; in the stable section, the state factors are adjusted through the adjusting method proposed by the present invention.

[0089] Specifically, the weights of various state factors in the preheating stage are moisture content, color factor, and texture factor from high to low;

[0090] The weights of various state factors in the color fixing stage are color factor, texture factor, and moisture content from high to low;

[0091] The weights of various state factors in the drying stage are moisture content, texture factors, and color factors from high to low.

[0092] That is, according to the actual situation of each drying stage, the weight ratio of different state factors in each drying stage is set, so that the focus of each drying stage is consistent with the actual drying situation, ensuring that the corresponding adjustment effect can be achieved when the drying parameters are adjusted.

[0093] The following is a specific calculation example of the present invention:

[0094] Among them, R is the moisture content of tobacco, S is the texture factor, and C is the color factor. In the stable stage of each sub-stage, at a certain interval T, the tobacco status Rt, St, Ct currently collected and calculated is sorted and compared with the ideal status R, S, C preset by the indicator process curve;

[0095] Calculate the difference between each state:

[0096] R difference = (M initial - Mt) / M initial - R (M initial is the weight of the tobacco in the flue-curing room before curing), that is, R deviation = R difference / R;

[0097] S difference = St-S; S deviation = S difference / S;

[0098] C difference = Ct-C, C deviation = C difference / C.

[0099] Among them, in the preheating period, according to the change of the influence weight of each state as the drying progresses, the preheating stage is generally divided into three drying stages: the first preheating stage, the second preheating stage, and the third preheating stage.

[0100] The weight of each state indicator in different stages is different, so the influencing factors of the offset rate are also different. Specific examples are as follows. (The meaning of the stage here is different from the detailed stage of the baking process. The detailed stage may be composed of several preheating stages, such as the low temperature adaptation stage and the temperature rise balance stage in the above example.)

[0101] In the first stage of preheating, moisture content: color: texture = 5:2:3;

[0102] In the second stage of preheating, moisture content: color: texture = 9:6:5;

[0103] Preheating third stage: moisture content: color: texture = 8:7:5.

[0104] Generally speaking, during the preheating period, R bias is the first weight, C bias is the second weight, and S bias is the third weight.

[0105] During the color fixing period, the influencing factors of each state are relatively stable, moisture content: color: texture = 7:8:5. It can be seen that C is the first weight, R is the second weight, and S is the third weight.

[0106] During the drying period, the influencing factors of each state are stable, moisture content: color: texture = 9:4:7, R is the first weight, S is the second weight, and C is the third weight.

[0107] When the R deviation, C deviation, and S deviation are all within the difference offset range, the current preset parameters remain unchanged; if they exceed the offset range, the excess state weight jumps to the first weight, and the temperature, humidity, and drying time are adjusted according to this state.

[0108] If R is smaller than the lower limit of the offset range, it means that the moisture content of the tobacco leaves is higher than the expected effect content. In this case, the drying time Hc2 needs to be extended while keeping the target drying temperature, humidity and ventilation unchanged.

[0109] If R is higher than the upper limit of the deviation range, it means that the drying is overdrying and the drying time needs to be shortened and the target temperature Tn needs to be lowered if necessary.

[0110] If multiple states are beyond the offset range, the offset sizes need to be compared, and weighted comparison is required. For example, in the first stage of preheating, |R offset|*5 is compared with |C offset|*2 and |S offset|*3, and the factor with the largest value is calculated. The corresponding setting parameters are adjusted in time to pull this state back to avoid over-baking or under-baking.

[0111] The present invention also proposes a drying system, which uses the above control method to adjust the drying parameters of each drying stage so that the state factor with the greatest impact on the quality of the current drying stage returns to a reasonable deviation range, thereby ensuring the stability of the drying effect and the consistency of product quality.

[0112] The drying system specifically includes: a weighing sensor for weighing the weight of tobacco leaves, an image sensor for capturing images of the surface of tobacco leaves, and a heat pump dryer for drying tobacco leaves; a controller for calculating the moisture content of tobacco leaves based on weight parameters detected by the weighing sensor and image information detected by the image sensor, and evaluating color and texture factors of the tobacco leaves, and controlling the heat pump dryer based on the information obtained.

[0113] The weighing sensor can obtain the dynamic change data of the weight of tobacco leaves during the drying process, and indirectly deduce the real-time moisture content of tobacco leaves by comparing and calculating the weight parameters at different time points; the image sensor obtains the image information of the tobacco leaf surface through a high-definition camera, and analyzes the color and texture characteristics of the tobacco leaves in combination with the image processing algorithm, thereby evaluating the status of color factors and texture factors. Image processing technology includes but is not limited to color extraction, texture analysis and contrast adjustment, which can efficiently identify the color changes and texture characteristics of tobacco leaves; the heat pump dryer is responsible for providing the heat energy and environmental regulation capabilities required for drying. Through the instructions issued by the controller, the heat pump dryer can flexibly adjust the temperature, humidity and drying time to meet the regulation requirements of different state factors. The controller combines the set indicator process curve to dynamically calculate the moisture content of tobacco leaves and evaluate the color and texture state factors in real time. The controller uses advanced control algorithms to adjust the parameter settings of the heat pump dryer according to the actual deviation to ensure that the drying process always meets the process requirements.

[0114] The integration and collaboration of multiple sensors in the drying system proposed in the present invention can obtain key status information of tobacco leaves in real time and comprehensively, improve the consistency of drying quality and production efficiency, and reduce energy consumption through heat pump technology.

[0115] It should be noted that the terms used above are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0116] Unless otherwise specifically stated, the relative arrangement of the parts and steps described in these embodiments, numerical expressions and numerical values ​​do not limit the scope of the present invention. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be regarded as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0117] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0118] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A control method for a drying system, characterized in that: Includes steps: Monitor status information reflecting tobacco drying quality; Determine the state factor that has the greatest impact on the quality of the current drying stage according to the actual index value of each state factor in the current drying stage and the priority of the factor in the state information; Adjust the drying parameters so that the state factor that has the greatest impact on the quality of the current drying stage returns to a reasonable deviation range.

2. The control method of the drying system according to claim 1, characterized in that: According to the actual index value of each state factor in the current drying stage and the priority of the factor in the state information, the state factor having the greatest impact on the quality of the current drying stage is determined to include: Calculate the deviation rate of each state factor relative to the actual index value of the current drying stage. When there are multiple state factors with deviation rates exceeding the preset deviation range, determine the state factor with the greatest impact on the quality of the current drying stage based on the weight ratio of each state factor in the current drying stage.

3. The control method of the drying system according to claim 1, characterized in that: According to the actual index value of each state factor in the current drying stage and the priority of the factor in the state information, the state factor having the greatest impact on the quality of the current drying stage is determined to include: The deviation rate of each state factor relative to the actual index value of the current drying stage is calculated. When there is only one state factor whose deviation rate exceeds the preset deviation range, the state factor is determined to be the state factor with the greatest impact on the quality of the current drying stage.

4. The control method of the drying system according to claim 2 or 3, characterized in that: Calculation of the deviation rate of each state factor relative to the actual index value of the current drying stage specifically includes: An actual process curve is generated by acquiring the actual value and time value of the detected state factor and comparing it with the corresponding index process curve. The state factor offset rate is obtained by subtracting the target value in the index process curve from the actual value in the actual process curve and dividing it by the target value.

5. The control method of the drying system according to claim 1, characterized in that: The state factors included in the state information are specifically: moisture content, color factor and texture factor.

6. The control method of the drying system according to claim 5, characterized in that: When the moisture content is the state factor that has the greatest impact on the quality of the current drying stage, the drying parameters to be adjusted are specifically: Determine whether the deviation rate of the moisture content deviates from the upper limit value of the preset deviation range; If yes, lower the drying temperature and shorten the drying time; if no, extend the drying time.

7. The control method of the drying system according to claim 5, characterized in that: When the color factor is the state factor that has the greatest impact on the quality of the current drying stage, the drying parameters to be adjusted are specifically: Determine whether the deviation rate of the color factor deviates from the upper limit value of the preset deviation range; if so, reduce the drying temperature and shorten the drying time; if not, increase the drying temperature and drying humidity, and extend the drying time.

8. The control method of the drying system according to claim 5, characterized in that: When the texture factor is the state factor that has the greatest impact on the quality of the current drying stage, the adjustment of the drying parameters specifically includes: If the texture factor is in the rising stage of its corresponding index process curve, determine whether the deviation rate of the texture factor deviates from the upper limit of the preset deviation range; if so, reduce the drying temperature, reduce the drying humidity, and shorten the drying time; if not, increase the drying temperature, increase the drying humidity, and extend the drying time; If the texture factor is in the downward rising stage of its corresponding indicator process curve, determine whether the deviation rate of the color factor deviates from the upper limit value of the preset deviation range; if so, increase the drying temperature and extend the drying time; if not, reduce the drying temperature and drying humidity, and shorten the drying time.

9. The control method of the drying system according to any one of claims 6 to 8, characterized in that: The drying stage includes: a preheating stage, a color fixing stage and a drying stage; each stage is divided into multiple sub-stages according to demand, and the weight proportion of each state factor in each sub-stage is different.

10. The control method of the drying system according to claim 9, characterized in that: The drying parameters included in each of the drying sub-stages are: target drying temperature Tn, target drying humidity Wn; and each of the drying sub-stages is divided into: an adjustment section for achieving the target drying temperature Tn and target drying humidity Wn of this stage, and a stabilization section for executing the drying parameter adjustment step.

11. The control method of the drying system according to claim 9, characterized in that: The weights of the various state factors in the preheating stage are moisture content, color factor and texture factor from high to low; The weights of the various state factors in the color fixing stage are color factor, texture factor, and moisture content from high to low; The weights of the various state factors in the drying stage are moisture content, texture factor, and color factor from high to low.

12. A drying system, characterized in that: The drying parameters of each drying stage are adjusted using the control method described in any one of claims 1 to 11.

13. The drying system according to claim 12, characterized in that: include: Weighing sensors for weighing tobacco leaves, image sensors for taking images of the surface of tobacco leaves, and heat pump dryers for drying tobacco leaves; The controller calculates the moisture content of the tobacco leaves according to the weight parameters detected by the weighing sensor and the image information detected by the image sensor, and evaluates the color factors and texture factors of the tobacco leaves, and controls the heat pump dryer according to the obtained information.

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