Hydraulic pressure self-adaptive adjusting system of single-screw press

Abstract

The invention relates to the technical field of pressure regulation and control, in particular to a hydraulic pressure self-adaptive regulation system of a single-screw press. The system comprises a data acquisition module for acquiring historical squeezing data; the squeezing efficiency analysis module is used for determining the squeezing efficiency at the moment by combining the material characteristics, the trend change of the torque data and the pressure data; the reference time period acquisition module is used for dividing a historical squeezing time sequence and screening a reference time period according to the similarity with the current squeezing time sequence in combination with squeezing efficiency and an oil outlet condition; the reference time period weight analysis module considers the temperature correlation influence to determine the reference weight of the reference time period; and the pressure regulation module analyzes the current target pressure through the reference weight to carry out pressure regulation. According to the method, historical stages are divided in combination with material characteristics to analyze and match similar conditions, historical reference credibility is adjusted through temperature correlation influence, accurate rationality of pressure control is improved, and camellia oil squeezing quality is improved while squeezing efficiency is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of pressure regulation, and in particular to a hydraulic pressure self-adaptive regulation system for a single screw press. Background Art

[0002] A single-screw press propels material forward through the rotation of the screw shaft, utilizing the extrusion force generated by the gradually decreasing volume of the screw chamber to achieve solid-liquid separation. Its core function is to mechanically expel liquid from the material through the gaps in the screen drum, while solids are discharged through the outlet. In the camellia seed oil extraction process, the processed camellia seeds are placed in a single-screw press for hydraulic pressing. The rotation of the screw propels the material forward, gradually increasing pressure to encourage the oil to flow out. The adaptability of this pressure has a direct impact on oil extraction and product quality.

[0003] In the pressure regulation of existing single-screw presses, traditional control pressure regulation mostly relies on single pressure data for adjustment. However, in camellia oil production, since the material state will be affected by resistance changes and temperature, the pressure regulation requirements at each stage of pressing may be different. If the adjustment of material state is ignored, it is very likely that the material will be pressed into a paste or even abnormal equipment load will occur, or the efficiency and pressure increase will cause the temperature to exceed the standard and damage the oil quality, etc., and it is impossible to ensure the pressing efficiency while taking into account the pressing quality. Summary of the Invention

[0004] In order to solve the technical problem in the prior art that it is impossible to ensure the squeezing efficiency while taking into account the squeezing quality, the purpose of the present invention is to provide a hydraulic pressure adaptive adjustment system for a single screw press. The technical solution adopted is as follows:

[0005] The present invention provides a single screw press hydraulic pressure adaptive regulation system, the system comprising:

[0006] The data acquisition module is used to obtain the pressure data, temperature data and torque data of the pressing chamber at each moment in each historical pressing process, as well as the oil output of the oil outlet;

[0007] The pressing efficiency analysis module is used to obtain the pressing efficiency index at each moment based on the fluctuation trend of the torque data at each moment, as well as the pressure data and the characteristics of the pressed raw materials;

[0008] The reference period acquisition module is used to segment the time sequence of the pressing process according to the sudden changes in pressure data during each pressing process to obtain the divided time periods; based on the pressing efficiency index and oil output of each divided time period, the time period with high similarity to the current time period is selected as the reference time period;

[0009] The reference period weight analysis module is used to determine the reference weight of each reference period based on the impact of temperature data deviation at the moment of each reference period and the related change trend between the pressing efficiency index, as well as the temperature data deviation between the reference period and the current period;

[0010] The pressure adjustment module is used to obtain the target pressure data of the current period based on the reference weights and pressure data of all reference periods; and to adjust the pressure according to the deviation between the current pressure data and the target pressure data.

[0011] Furthermore, the method for obtaining the squeezing efficiency index includes:

[0012] Obtain the moisture content and shell content of the feed raw materials in each pressing process; obtain the material property difference index of each pressing process based on the expected deviation degree of the moisture content and shell content in each pressing process;

[0013] According to the stable increasing trend of torque data at each moment in each squeezing process, the squeezing function load index at each moment is obtained;

[0014] The ratio of the pressure data at each moment in each pressing process to the pressing function load index is taken as the pressure efficiency; the pressing efficiency index is obtained by combining the material property difference index and the pressure efficiency.

[0015] Furthermore, the method for obtaining the material property difference index includes:

[0016] The difference between the moisture content of each pressing process and the expected moisture content is taken as the moisture deviation of each pressing process; the difference between the shell content of each pressing process and the expected shell content is taken as the shell deviation of each pressing process;

[0017] The product of the moisture content deviation and the shell content deviation in each pressing process was calculated and normalized to obtain the material property difference index in each pressing process.

[0018] Furthermore, the method for obtaining the squeezing function load index includes:

[0019] For any moment in the squeezing process, the slope of the torque data at that moment is obtained as the trend degree; the product of the torque data at that moment and the trend degree is normalized to obtain the load lifting degree at that moment;

[0020] Within the preset range at that moment, the variance of all torque data is normalized to obtain the squeezing fluctuation at that moment; and the squeezing function load index at that moment is obtained by combining the load increase and squeezing fluctuation at that moment.

[0021] Furthermore, the method for obtaining the divided time periods includes:

[0022] During each squeezing process, the inflection points of the pressure data in the time series are obtained; and the time period corresponding to each two adjacent inflection points is used as each divided time period.

[0023] Furthermore, the method for obtaining the reference period includes:

[0024] For any divided time period, the ratio between the sum of the oil output values ​​at all moments in the divided time period and the total weight of the raw material fed into the pressing process during the divided time period is used as the oil output status index of the divided time period; the average value of the pressing efficiency index at all moments in the divided time period and the oil output status are combined to obtain the pressing condition index of the divided time period;

[0025] All divided time periods are clustered using the pressing condition index as a metric to obtain a time period clustering cluster; the pressing condition index of the current time period is obtained; when the difference between the mean of all the pressing condition indexes in the time period clustering cluster and the pressing condition index of the current time period is the smallest, the divided time period in the corresponding time period clustering cluster is used as the reference time period of the current time period.

[0026] Furthermore, the method for obtaining the reference weight includes:

[0027] The difference between the temperature data at each moment and the expected temperature data is taken as the temperature difference impact value at each moment;

[0028] For any reference period, the correlation between the squeezing efficiency index and the temperature difference impact value in the reference period in time is used as the trend consistency index of the reference period; the product of the mean of all squeezing efficiency indexes in the reference period and the trend consistency index is used as the squeezing efficiency of the reference period;

[0029] Calculate the difference between the mean of all temperature impact values ​​in the reference period and the mean of all temperature impact values ​​in the current period as the temperature risk value for the reference period;

[0030] The product of the negative correlation mapping value of the temperature risk value and the squeezing efficiency is normalized to obtain the reference weight of the reference period.

[0031] Furthermore, the method for acquiring the target pressure data includes:

[0032] The pressure data corresponding to the moment of maximum oil output in each reference period is used as the optimal pressure data for each reference section;

[0033] The optimal pressure data of all reference periods are weighted and summed using the reference weight as the weight to obtain the target pressure data of the current period.

[0034] Furthermore, the pressure adjustment according to the deviation between the current pressure data and the target pressure data includes:

[0035] The difference between the current pressure data and the target pressure data is taken as the current pressure deviation; when the pressure deviation is less than the preset adjustment threshold, no adjustment is required;

[0036] If the pressure deviation is greater than or equal to the preset adjustment threshold, the current pressure data is adjusted in a step-by-step manner according to the size of the pressure deviation until the pressure deviation is less than the preset adjustment threshold.

[0037] Furthermore, the method for obtaining the current time period includes:

[0038] Get the most recent extreme value of the pressure data before the current moment; when the time length between the most recent extreme value and the current moment is greater than or equal to the minimum length of the time period, the time range between the most recent extreme value and the current moment is used as the current time period; otherwise, the time range with the minimum length of the time period before the current time period is used as the current time period.

[0039] The present invention has the following beneficial effects:

[0040] The present invention uses historical analysis of the material properties of the feed, considers the trend changes in torque data to measure the situation of pressing obstruction, collects pressure data to preliminarily quantify the pressing efficiency at the moment, considers the pressing effect in multiple dimensions, and avoids subsequent adjustment deviations due to unclear material properties. Considering the stage adaptation problem, by dividing the historical data and combining it with the current similarity analysis of the pressing efficiency and oil output, the historical data adapted to the current working conditions is used as a basis to improve the credibility and rationality of the target pressure analysis. Then, the reference weight of the reference time period is determined considering the influence of temperature correlation, and the value of the reference time period with low reference is reduced by the influence of temperature difference in historical data, thereby improving the accuracy of the target pressure analysis. Finally, the current expected target pressure is analyzed by reference weight to adjust the pressure, making the current pressure adjustment more adaptable. The present invention combines the material characteristics to divide the historical stage analysis to match similar situations, and adjusts the historical reference credibility by temperature correlation, thereby improving the accuracy and rationality of pressure control, while ensuring the pressing efficiency and improving the quality of camellia oil pressing. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions and advantages of the embodiments of the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the prior art descriptions. 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 any creative work.

[0042] Figure 1 A structural diagram of a hydraulic pressure adaptive adjustment system for a single screw press provided by one embodiment of the present invention;

[0043] Figure 2 A flow chart of a method for obtaining a pressing efficiency index provided by one embodiment of the present invention;

[0044] Figure 3 A schematic diagram of the distribution of a pressing efficiency index and the influence of temperature difference provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0045] To further illustrate the technical means and effectiveness of the present invention in achieving its intended objectives, the following, in conjunction with the accompanying drawings and preferred embodiments, describes in detail the specific implementation, structure, features, and effectiveness of a single-screw press hydraulic pressure adaptive adjustment system proposed by the present invention. In the following description, references to different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics of one or more embodiments may be combined in any suitable manner.

[0046] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0047] The specific scheme of the single screw press hydraulic pressure adaptive adjustment system provided by the present invention is described in detail below with reference to the accompanying drawings.

[0048] See also Figure 1 , which shows a structural diagram of a single-screw press hydraulic pressure adaptive adjustment system provided by an embodiment of the present invention, the system includes: a data acquisition module 101, a pressing efficiency analysis module 102, a reference time period acquisition module 103, a reference time period weight analysis module 104 and a pressure adjustment module 105.

[0049] The data acquisition module 101 is used to acquire the pressure data, temperature data and torque data of the pressing chamber at each moment in each historical pressing process, as well as the oil output of the oil outlet.

[0050] The hydraulic production process of the single screw press is mainly as follows: the raw materials are shelled and crushed, the materials enter from the feed port, and the screw shaft rotates to push the materials to the discharge port. As the volume of the spiral cavity decreases, the materials are squeezed and the liquid flows out through the screen drum. The extrusion force can be changed by adjusting the terminal pressure in the hydraulic system. The greater the pressure, the more complete the discharge. However, excessive pressure may also cause excessive extrusion of solids, resulting in abnormal losses such as breakage and blockage.

[0051] In order to adaptively adjust the pressing process of camellia seed oil, in an embodiment of the present invention, the material state of the raw material fed for pressing is collected. A near-infrared spectrometer is installed above the feed hopper to obtain the moisture content data and shell content data of the fed tea seeds based on the spectral band characteristics, and the total weight data of the feed is collected at the feed hopper to perform initial data collection for each batch of raw materials for pressing.

[0052] Relevant data is monitored at every moment during each pressing process. In this embodiment of the present invention, a pressure sensor at the end of the pressing chamber monitors pressure data, and distributed temperature monitoring is installed within the pressing chamber to obtain temperature data within the pressing chamber. Two sets of torque sensors are installed at both ends of the screw shaft to obtain torque data, which reflects material resistance. The greater the resistance, the higher the torque data. Oil flow is also monitored during the continuous pressing process. A laser oil residue detector and an electromagnetic flowmeter are installed at the oil outlet to obtain oil output.

[0053] This embodiment of the present invention provides a historical reference for adaptive adjustment of current pressure data based on the homogeneity of historical pressing operations. Therefore, data collected from multiple historical pressing processes is analyzed. The number of historical batches can be 7, and the collection frequency can be once per second. It should be noted that equipment installation, collection, and data configuration are well-known techniques to those skilled in the art. Implementers can adjust these techniques based on specific implementation scenarios and are not limited here.

[0054] The pressing efficiency analysis module 102 is used to obtain the pressing efficiency index at each moment according to the fluctuation trend of the torque data at each moment, as well as the pressure data and the characteristics of the pressed raw material.

[0055] First, we analyze the pressing efficiency at each moment, taking into account the influence of material properties. We evaluate the pressing load during the pressing process by analyzing the trend of torque data. We then match and analyze the pressure data with the resistance load to quantify whether there is excessive or insufficient pressure on the raw material. Furthermore, material properties directly determine the difficulty of pressing. For example, materials with a suitable high moisture content and low shell content are more efficient to press, resulting in lower pressing difficulty and better efficiency.

[0056] Therefore, the pressing efficiency is preliminarily quantified by combining the trend change of torque data and pressure data with the material characteristics of the raw material. Preferably, in the embodiment of the present invention, the method for obtaining the pressing efficiency index can be found in Figure 2 , which shows a flow chart of a method for obtaining a pressing efficiency index provided by one embodiment of the present invention, the method comprising the following steps:

[0057] S201: obtaining the moisture content and shell content of the feed raw material in each pressing process; and obtaining a material property difference index for each pressing process based on the expected deviation degree of the moisture content and shell content in each pressing process.

[0058] After the raw materials undergo the shelling process, their moisture content and shell content will not change in the subsequent pressing process. The moisture content determines the plasticity and fluidity of the material, and the shell content affects the pressure transmission efficiency and impurity content. Based on the moisture content and shell content of the feed raw materials obtained in each pressing process, the expected deviation degree of the moisture content and shell content is analyzed to obtain the material property difference index of each pressing process.

[0059] The closer the moisture content and shell content of the raw material are to the expected standard values, the more stable the material properties are, providing more balanced material properties for the operation of the pressing chamber. Therefore, in this embodiment of the present invention, the difference between the moisture content of each pressing process and the expected moisture content is used as the moisture deviation of each pressing process, and the difference between the shell content of each pressing process and the expected shell content is used as the shell deviation of each pressing process. The expected moisture content and expected shell content can be set by the implementer based on the specific implementation scenario, such as an expected moisture content of 18% and an expected shell content of 5%, which are not limited here.

[0060] The product of the moisture content deviation and shell content deviation for each pressing process is calculated and normalized to obtain the material property difference index for each pressing process. The smaller the deviation between the moisture content and shell content data from the appropriate expectations, that is, the smaller the material property difference index, the more balanced the current material properties are, and the smaller the pressure adaptive adjustment range required in the pressing chamber can be. Conversely, the larger the material property difference index during the current pressing process, the more likely the material is affecting the pressing efficiency.

[0061] It should be noted that normalization is a technical means well known to those skilled in the art. The normalization method may be linear normalization or standard normalization, etc. The specific normalization method is not limited here.

[0062] S202: Obtain a pressing function load index at each moment according to a stable increasing trend of the torque data at each moment in each pressing process.

[0063] The torque data reflects the material resistance in the pressing chamber during the pressing process. When the torque data value is larger and shows an upward trend, it means that the hardness of the material in the current pressing chamber is too high, the hydraulic pressure may be insufficient, and it is difficult to effectively complete the pressing of the tea seed material. This quantifies the load condition of the current pressing state.

[0064] In this embodiment of the present invention, at any moment in the squeezing process, the slope of the torque data at that moment is obtained as the trend degree. A larger slope indicates a more significant upward trend. The product of the torque data at that moment and the trend degree is normalized to obtain the load increase degree at that moment. A larger load increase degree indicates a greater driving resistance of the screw shaft of the squeezing machine, that is, a stronger squeezing load during the squeezing process.

[0065] Then, within a preset range at that moment, the variance of all torque data is normalized to obtain the squeezing fluctuation at that moment. The variance within a local range reflects the stability of the data. The smaller the variance of the torque data, the better the torque data stability, the smoother the screw shaft of the squeezing machine operates, and the lower the squeezing workload in the squeezing chamber. In this embodiment of the present invention, the preset range can be set to the 20 seconds before each moment. The specific range can be adjusted by the implementer and is not limited here.

[0066] Therefore, the pressing function load index at that moment is obtained by combining the load increase and the pressing fluctuation at that moment. In an embodiment of the present invention, the product of the load increase and the pressing fluctuation at that moment is used as the pressing function load index at that moment, reflecting the load state of the current pressing work. The larger the pressing function load index, the greater the material resistance.

[0067] S203: Combining the pressure data at each moment, the pressing function load index, and the material property difference index, to obtain a pressing efficiency index at each moment.

[0068] Combined with the pressure data during the pressing process, the ratio of the pressure data at each moment in each pressing process to the pressing function load index is used as the pressure efficiency, reflecting whether the current pressure adjustment is matched to the material resistance. A smaller ratio indicates that the pressing function load reflected by the press torque is large and the pressure is not keeping up, resulting in insufficient oil output and low pressing efficiency. Conversely, a higher pressure efficiency indicates that the press pressure is too high while the actual pressing load is low during the pressing operation. In other words, the torque data is affected by weak material resistance and the pressure efficiency is too high.

[0069] Combining the material property difference index and the pressure efficiency, a pressing efficiency index is obtained. The smaller the material property difference index is, the more positive feedback it has on the pressure efficiency of the pressing process. The more stable the material properties are, the more beneficial it is to the pressing efficiency of the pressing process, and the higher the pressing efficiency is. In an embodiment of the present invention, the product of the value of the negative correlation mapping of the material property difference index and the pressure efficiency is used as the pressing efficiency index. It should be noted that negative correlation mapping is a technical means well known to those skilled in the art, such as using an inverse proportional value or a negative exponential power form, and is not limited or elaborated on here.

[0070] The reference period acquisition module 103 is used to segment the timing of the pressing process according to the sudden change of pressure data during each pressing process to obtain the divided time periods; based on the pressing efficiency index and oil output in each divided time period, the time period with high similarity to the current time period is selected as the reference time period.

[0071] Camellia oil production varies at different stages of the pressing process. For example, the oil output naturally decreases in the later stages of pressing. In addition, the change in pressing efficiency during the pressing process has a certain linear relationship with the feed amount. When the feed amount is too much, the material accumulates in the pressing chamber, and the hardness of the material may be higher, which is more likely to affect the torque data of the screw shaft, thereby reducing the pressure efficiency. Moreover, if the feed amount is larger, it is more likely to cause a heating effect in the difficult pressing mode, and the temperature difference in the pressing chamber will also have different effects.

[0072] To analyze the historical pressing process by screening more reliable historical periods of similar operating conditions for the current period, the historical pressing process is divided. In this embodiment of the present invention, the pressure data's adjustment change inflection points are used as dividing points. During each pressing process, the inflection points of the pressure data are obtained in the time series, and the time period corresponding to each two adjacent inflection points is used as each divided period. Each divided period reflects a pressure change trend segment. The inflection point of the pressure data represents the turning point where the pressure suddenly rises or falls. The acquisition of inflection points is a well-known technical method well known to those skilled in the art and will not be elaborated here.

[0073] Then, the divided time periods are analyzed and screened for similar production conditions based on the pressing efficiency and oil output, and a reference period with high consistency in working conditions is obtained to provide analytical value for the current period. The method for determining the current period includes: obtaining the most recent extreme value of the pressure data before the current moment. When the time length between the most recent extreme value and the current moment is greater than or equal to the minimum length of the divided period, the time range between the most recent extreme value and the current moment is used as the current period. This indicates that the reliability of the working condition analysis before the current period is high and complete. Otherwise, the time range with the minimum length of the divided period before the current period is used as the current period. If the period is too short and the data sample size is insufficient, it is easy to cause distortion of similarity judgment due to accidental fluctuations. Therefore, by lengthening, the time series analysis before the current moment is made more reliable.

[0074] Furthermore, by matching the characteristics of squeezing efficiency and oil output, reference time periods with high consistency in working conditions are screened, providing an effective historical basis for pressure regulation in the current time period. In an embodiment of the present invention, for any divided time period, the ratio between the sum of the oil output values ​​at all times in the divided time period and the total feed weight of the raw materials in the squeezing process in the divided time period is used as the oil output status indicator of the divided time period. The oil output sum value reflects the output capacity of camellia oil in the divided time period. The ratio relationship with the total feed weight is used to standardize the work of different squeezing processes, eliminate the interference that more feed means more oil output, and facilitate feature comparison between different time periods.

[0075] Combined with the mean of the pressing efficiency index at all moments in the divided time period and the oil output status, the pressing working condition index of the divided time period is obtained. In an embodiment of the present invention, the product of the mean of the pressing efficiency index at all moments in the divided time period and the oil output status is normalized as the pressing working condition index of the divided time period to measure the working condition characteristics.

[0076] Furthermore, all time periods are clustered using the crushing condition index as a metric to obtain time period clusters. Time periods with similar crushing condition indexes are clustered and filtered through clustering. In an embodiment of the present invention, the clustering algorithm may employ K-means clustering, which is a well-known technique for those skilled in the art and is not limited or elaborated upon herein.

[0077] Obtain the current time period's squeezing condition indicators. Compare the characteristics of the current moment to the mean of all squeezing condition indicators in the time period cluster. When the difference between the mean of all squeezing condition indicators in the time period cluster and the current time period's squeezing condition indicator is minimal, it indicates that the operating condition characteristics of the time period in the cluster are more similar to those of the current time period. The corresponding time period in the time period cluster is used as the reference time period for the current time period. The pressure of the reference data segment can be used as the basis for adaptive pressure adjustment at the current moment.

[0078] The reference period weight analysis module 104 is used to determine the reference weight of each reference period based on the impact of temperature data deviation at each reference period and the related change trend between the pressing efficiency index, as well as the temperature data deviation between the reference period and the current period.

[0079] During the cold-pressing process of camellia oil, some reference data segments, while matching the operating conditions, exhibit low oil yield efficiency or significant temperature differences. Direct analysis and adjustment results in poor results. Since camellia oil is heat-sensitive, temperature control within the press chamber is essential during the cold-pressing process. Therefore, in practice, both temperature and pressure factors can affect tea seed oil yield and quality.

[0080] Due to the existence of temperature limit constraints, the more consistent the adjustment logic of the reference period is with the current demand, the more credible the situation in the reference period is. For example, when the squeezing efficiency in the period gradually decreases, the pressure needs to be increased to improve the squeezing efficiency. Continuing to increase the squeezing machine pressure will also increase the temperature in the squeezing chamber, making the temperature deviation higher. Therefore, there is a trend change related to the squeezing efficiency and temperature deviation.

[0081] Therefore, combining the reliability of temperature deviation and pressure trend adjustment, quantify the consistency of working conditions within each reference period. When the working condition consistency is higher, the direction of pressure adjustment reflected by the squeezing efficiency data and temperature influence is the same, and the pressure adjustment of the reference data section is more referenceable. Figure 3, which shows a schematic diagram of the distribution of a pressing efficiency index and temperature difference influence provided by an embodiment of the present invention, and the different changing trends of the pressing efficiency index 1 and the pressing efficiency index 2. When the temperature difference influence data gradually increases, if the pressing efficiency index shows a trend of 2, it is inconsistent with the adjustment of the press pressure, that is, the consistency is poor and the reference is lower.

[0082] In an embodiment of the present invention, a method for obtaining a reference weight includes:

[0083] The difference between the temperature data at each moment and the expected temperature data is used as the temperature difference impact value at each moment. The greater the temperature offset, the greater the temperature difference impact. The implementer of the expected temperature data can set it according to the specific implementation situation and is not limited here.

[0084] For any reference period, the temporal correlation between the squeezing efficiency index and the temperature difference impact value for that reference period is used as the trend consistency index for that reference period. In embodiments of the present invention, the temporal correlation between the squeezing efficiency index and the temperature difference impact value can be obtained using the Pearson correlation coefficient. A larger Pearson correlation coefficient indicates a higher trend consistency index, reflecting a higher degree of trend consistency and greater reference value for the reference period. It should be noted that the Pearson correlation coefficient is a well-known technique for those skilled in the art and will not be elaborated upon here.

[0085] Then, the product of the mean of all squeezing efficiency indicators in the reference period and the trend consistency index is taken as the squeezing efficiency of the reference period. Through consistency analysis and adjustment, the higher the trend consistency index, the more credible the adjustment, and the larger the squeezing efficiency index, the better the squeezing work evaluation result, so the greater the squeezing efficiency.

[0086] Further considering the degree of consistency in temperature deviation between the reference period and the current period, the difference between the mean of all temperature impact values ​​in the reference period and the mean of all temperature impact values ​​in the current period is calculated as the temperature risk value of the reference period. The smaller the temperature risk value, the smaller the impact of the temperature difference, and the more reliable the reference period matching reference degree.

[0087] Therefore, the product of the negative correlation mapping value of the temperature risk value and the squeezing efficiency is normalized to obtain the reference weight of the reference period. The higher the reference weight, the higher the credibility of the comparison in the current pressure analysis.

[0088] The pressure adjustment module 105 is configured to obtain target pressure data for the current period based on the reference weights and pressure data of all reference periods, and to perform pressure adjustment based on the deviation between the current pressure data and the target pressure data.

[0089] By using the reference weights of each reference period as the distribution ratio, the optimal pressure value within the period is extracted, and the currently desired target pressure is obtained for correction. In this embodiment of the present invention, the pressure data corresponding to the moment of highest oil output in each reference period is used as the optimal pressure data for each reference period to ensure oil quality. The optimal pressure data for all reference periods are weighted and summed using the reference weights as the weights to obtain the target pressure data for the current period. The target pressure data is the desired pressure value adapted to the current state, obtained through comparative analysis of historical pressing history.

[0090] Finally, the pressure is adaptively adjusted based on the deviation between the current pressure data and the target pressure data. In an embodiment of the present invention, the difference between the current pressure data and the target pressure data is used as the current pressure deviation. When the pressure deviation is less than the preset adjustment threshold, the deviation between the current pressure and the target pressure is small, which is close to the expected optimal state. No additional adjustment is required, so frequent fluctuations are avoided to affect the pressing stability.

[0091] If the pressure deviation is greater than or equal to the preset adjustment threshold, it means that there is insufficient pressure resulting in insufficient oil output, or excessive pressure. The current pressure data is adjusted in a step-by-step manner according to the size of the pressure deviation, and the adjustment direction is close to the target pressure data. That is, if the pressure exceeds the target pressure data, the adjustment is reduced, and if the pressure is less than the target pressure data, the adjustment is increased until the pressure deviation is less than the preset adjustment threshold.

[0092] In this embodiment of the present invention, the preset adjustment threshold can be set to 0.3 MPa, and the step-by-step adjustment can be performed by adjusting the pressure by 30% of the pressure deviation at a 5-second interval. Furthermore, the temperature rise can be monitored during the adjustment process. If the temperature impact value exceeds 3°C, the target pressure can be reduced by 10% to ensure that the temperature environment is not affected.

[0093] In summary, the present invention uses historical analysis of the material properties of the feed, considers the trend change of the torque data to measure the situation of the pressing obstruction, collects the pressure data to preliminarily quantify the pressing efficiency at the moment, considers the pressing effect in multiple dimensions, and avoids subsequent adjustment deviations due to unclear material properties. Considering the stage adaptation problem, by dividing the historical data and combining the pressing efficiency and oil output to conduct a similarity analysis with the current situation, the historical data adapted to the current working conditions is used as a basis to improve the credibility and rationality of the target pressure analysis. Then, the reference weight of the reference time period is determined considering the influence of temperature correlation, and the value of the reference time period with low reference is reduced by the influence of temperature difference in historical data, thereby improving the accuracy of the target pressure analysis. Finally, the current expected target pressure is analyzed by reference weight to perform pressure regulation, so that the current pressure regulation is more adaptable. The present invention combines the material characteristics to divide the historical stage analysis to match similar situations, and adjusts the historical reference credibility by temperature correlation, thereby improving the accuracy and rationality of pressure control, while ensuring the pressing efficiency and improving the quality of camellia oil pressing.

[0094] It should be noted that the order in which the embodiments of the present invention are described above is for illustrative purposes only and does not necessarily represent the superiority or inferiority of the embodiments. The processes depicted in the accompanying drawings do not necessarily require the specific order or sequential order shown to achieve the desired results. In certain embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0095] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on the differences from other embodiments.

Claims

1. A single screw press hydraulic pressure adaptive adjustment system, characterized in that: The system comprises: The data acquisition module is used to obtain the pressure data, temperature data and torque data of the pressing chamber at each moment in each historical pressing process, as well as the oil output of the oil outlet; The pressing efficiency analysis module is used to obtain the pressing efficiency index at each moment based on the fluctuation trend of the torque data at each moment, as well as the pressure data and the characteristics of the pressed raw materials; The reference period acquisition module is used to segment the time sequence of the pressing process according to the sudden changes in pressure data during each pressing process to obtain the divided time periods; based on the pressing efficiency index and oil output of each divided time period, the time period with high similarity to the current time period is selected as the reference time period; The reference period weight analysis module is used to determine the reference weight of each reference period based on the impact of temperature data deviation at the moment of each reference period and the related change trend between the pressing efficiency index, as well as the temperature data deviation between the reference period and the current period; The pressure adjustment module is used to obtain the target pressure data of the current period based on the reference weights and pressure data of all reference periods; and to adjust the pressure according to the deviation between the current pressure data and the target pressure data.

2. The single screw press hydraulic pressure adaptive adjustment system according to claim 1, characterized in that: The method for obtaining the squeezing efficiency index includes: Obtain the moisture content and shell content of the feed raw materials in each pressing process; obtain the material property difference index of each pressing process based on the expected deviation degree of the moisture content and shell content in each pressing process; According to the stable increasing trend of torque data at each moment in each squeezing process, the squeezing function load index at each moment is obtained; The ratio of the pressure data at each moment in each pressing process to the pressing function load index is taken as the pressure efficiency; the pressing efficiency index is obtained by combining the material property difference index and the pressure efficiency.

3. The single screw press hydraulic pressure adaptive adjustment system according to claim 2, characterized in that: The method for obtaining the material property difference index includes: The difference between the moisture content of each pressing process and the expected moisture content is taken as the moisture deviation of each pressing process; the difference between the shell content of each pressing process and the expected shell content is taken as the shell deviation of each pressing process; The product of the moisture content deviation and the shell content deviation in each pressing process was calculated and normalized to obtain the material property difference index in each pressing process.

4. The single screw press hydraulic pressure adaptive adjustment system according to claim 2, characterized in that: The method for obtaining the squeezing function load index includes: For any moment in the squeezing process, the slope of the torque data at that moment is obtained as the trend degree; the product of the torque data at that moment and the trend degree is normalized to obtain the load lifting degree at that moment; Within the preset range at that moment, the variance of all torque data is normalized to obtain the squeezing fluctuation at that moment; and the squeezing function load index at that moment is obtained by combining the load increase and squeezing fluctuation at that moment.

5. The single screw press hydraulic pressure adaptive adjustment system according to claim 1, characterized in that: The method for obtaining the divided time periods includes: During each squeezing process, the inflection points of the pressure data in the time series are obtained; and the time period corresponding to each two adjacent inflection points is used as each divided time period.

6. The single screw press hydraulic pressure adaptive adjustment system according to claim 1, characterized in that: The method for obtaining the reference period includes: For any divided time period, the ratio between the sum of the oil output values ​​at all moments in the divided time period and the total weight of the raw material fed into the pressing process during the divided time period is used as the oil output status index of the divided time period; the average value of the pressing efficiency index at all moments in the divided time period and the oil output status are combined to obtain the pressing condition index of the divided time period; All divided time periods are clustered using the pressing condition index as a metric to obtain a time period clustering cluster; the pressing condition index of the current time period is obtained; when the difference between the mean of all the pressing condition indexes in the time period clustering cluster and the pressing condition index of the current time period is the smallest, the divided time period in the corresponding time period clustering cluster is used as the reference time period of the current time period.

7. The single screw press hydraulic pressure adaptive adjustment system according to claim 1, characterized in that: The method for obtaining the reference weight includes: The difference between the temperature data at each moment and the expected temperature data is taken as the temperature difference impact value at each moment; For any reference period, the correlation between the squeezing efficiency index and the temperature difference impact value in the reference period in time is used as the trend consistency index of the reference period; the product of the mean of all squeezing efficiency indexes in the reference period and the trend consistency index is used as the squeezing efficiency of the reference period; Calculate the difference between the mean of all temperature impact values ​​in the reference period and the mean of all temperature impact values ​​in the current period as the temperature risk value for the reference period; The product of the negative correlation mapping value of the temperature risk value and the squeezing efficiency is normalized to obtain the reference weight of the reference period.

8. The single screw press hydraulic pressure adaptive adjustment system according to claim 1, characterized in that: The method for acquiring the target pressure data includes: The pressure data corresponding to the moment of maximum oil output in each reference period is used as the optimal pressure data for each reference section; The optimal pressure data of all reference periods are weighted and summed using the reference weight as the weight to obtain the target pressure data of the current period.

9. The single screw press hydraulic pressure adaptive adjustment system according to claim 1, characterized in that: The pressure adjustment according to the deviation between the current pressure data and the target pressure data includes: The difference between the current pressure data and the target pressure data is taken as the current pressure deviation; when the pressure deviation is less than the preset adjustment threshold, no adjustment is required; If the pressure deviation is greater than or equal to the preset adjustment threshold, the current pressure data is adjusted in a step-by-step manner according to the size of the pressure deviation until the pressure deviation is less than the preset adjustment threshold.

10. The single screw press hydraulic pressure adaptive adjustment system according to claim 1, characterized in that: The method for obtaining the current time period includes: Get the most recent extreme value of the pressure data before the current moment; when the time length between the most recent extreme value and the current moment is greater than or equal to the minimum length of the time period, the time range between the most recent extreme value and the current moment is used as the current time period; otherwise, the time range with the minimum length of the time period before the current time period is used as the current time period.

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