Intelligent control method and system for output power of electric tracing band

Abstract

The invention relates to the technical field of constant temperature device control, in particular to an electric tracing band output power intelligent control method and system. The method comprises the following steps: firstly, acquiring temperature data, and further acquiring temperature variation trend uniformity according to the variation trend of the temperature data of all monitoring points; further segmenting the monitoring point, and obtaining a constant-temperature recovery coefficient of the pipeline at the current moment according to the change of the number of the monitoring point segments at adjacent moments; further obtaining a proportional gain correction coefficient at the current moment according to the delay synchronous change of the temperature data of the two adjacent monitoring points in combination with the temperature change trend uniformity and the constant-temperature recovery coefficient; and finally, adjusting the initial proportional gain coefficient at the current moment according to the proportional gain correction coefficient to control the output power of the electric tracing band, thereby realizing accurate regulation and control of the output power of the electric tracing band, and improving temperature uniformity, response speed and energy efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of constant temperature device control, and particularly relates to an intelligent control method and system for the output power of an electric tracing band. Background Art

[0002] Electric tracing is a technology that uses electric energy to generate heat. By installing an electric tracing band on the surface of a pipeline, heat is generated after power-on to compensate for the heat loss of the pipeline, thereby maintaining the temperature of the medium inside the pipeline.

[0003] Temperature control is generally carried out according to the difference between the set temperature and the actual temperature. The pipeline temperature is generally the average temperature of multiple monitoring points evenly distributed on the pipeline at the same moment. Therefore, for the same pipeline temperature, the temperature distribution at different positions of the pipeline may be uniform or non-uniform. Moreover, the reasons for the change in pipeline temperature are diverse, such as changes in ambient temperature and changes in the temperature of the liquid inside the pipeline. And the temperature change may recover quickly or slowly. Therefore, adjusting the output power of the electric tracing band only according to the difference between the set temperature and the actual temperature will result in inaccurate control of the output power of the electric tracing band, affecting the constant temperature control effect. Summary of the Invention

[0004] In order to solve the technical problem that the existing control of the output power of the electric tracing band is inaccurate and affects the constant temperature control effect, the purpose of the present invention is to provide an intelligent control method and system for the output power of the electric tracing band. The specific technical solutions adopted are as follows: An intelligent control method for the output power of an electric tracing band, the method includes: Obtain the temperature data of each sampling moment of all monitoring points on the pipeline; According to the change trend of the temperature data of all the monitoring points within the first preset neighborhood at the current moment, obtain the uniformity of the temperature change trend at the current moment; divide the temperature data at the same moment based on the APCA algorithm to correspondingly obtain segmented monitoring points; according to the change in the number of the segmented monitoring points at adjacent moments within the second preset neighborhood at the current moment, obtain the constant temperature recovery coefficient of the pipeline at the current moment; Along the flow direction of the substance inside the pipeline, according to the delayed synchronous change of the temperature data of two adjacent monitoring points within the third preset neighborhood at the current moment, obtain the temperature delay synchronization factor of the corresponding two monitoring points at the current moment; according to the distribution of all the temperature delay synchronization factors at the current moment, combine the uniformity of the temperature change trend and the constant temperature recovery coefficient to obtain the proportional gain correction coefficient at the current moment; Adjust the initial proportional gain coefficient at the current moment according to the proportional gain correction coefficient to control the output power of the electric tracing band.

[0005] Further, the method for obtaining the uniformity of the temperature change trend includes: Within the first preset neighborhood, obtain the first-order difference value and the second-order difference value that are the latest for the temperature data of each of the monitoring points; According to the dominant proportion situation among the non-positive and non-negative first-order difference values, obtain a same-trend factor; According to the difference between the non-negative first-order difference value and the non-positive first-order difference value, and in combination with the difference between the second-order difference value corresponding to the non-negative first-order difference value and the second-order difference value corresponding to the non-positive first-order difference value, obtain an opposite-trend factor; Fuse the same-trend factor and the opposite-trend factor to obtain the temperature change trend uniformity at the current moment.

[0006] Furthermore, the method for obtaining the same-trend factor includes: Among the non-positive first-order difference values and the non-negative first-order difference values, use the ratio of the number of the first-order difference values with the largest quantity to the number of the monitoring points as the same-trend factor.

[0007] Furthermore, the method for obtaining the constant-temperature recovery coefficient includes: Select any moment as the target moment. Among the monitoring point segments at the next adjacent moment of the target moment, obtain the number of the monitoring point segments that have a monitoring point intersection with each monitoring point segment of the target moment as the splitting number of each monitoring point segment of the target moment; Use the ratio of the sum value of all the splitting numbers corresponding to the target moment to the number of the monitoring point segments as the splitting degree coefficient of the target moment; Obtain the constant-temperature recovery coefficient at the current moment according to the overall characteristics of the splitting degree coefficient and the decreasing trend intensity of the number of the monitoring point segments; the overall characteristics of the splitting degree coefficient are negatively correlated with the constant-temperature recovery coefficient; the decreasing trend intensity is positively correlated with the constant-temperature recovery coefficient.

[0008] Furthermore, the method for obtaining the temperature delay synchronization factor includes: Match two adjacent monitoring points to form a matching group, and perform DTW matching on the temperature data corresponding to the two monitoring points in the matching group within the third preset neighborhood at the current moment; According to the slope distribution among the matching data pairs in the DTW matching result of each matching group, obtain the temperature delay synchronization factor of the matching group at the current moment.

[0009] Furthermore, the method for obtaining the temperature delay synchronization factor of the matching group at the current moment according to the slope distribution among the matching data pairs in the DTW matching result of each matching group includes: For each matching group, obtain the temperature delay synchronization factor of each matching group at the current moment according to the variance of the slopes between all matching pairs, the proportion of matching pairs with negative slopes, and the DTW distance.

[0010] Further, the method for obtaining the proportional gain correction coefficient includes: If the number of temperature delay synchronization factors greater than the first preset threshold at the current moment is greater than the second preset threshold, it is determined that there is a raw material switch; otherwise, it is determined that there is no raw material switch. When it is determined that there is no raw material switch, obtain the proportional gain correction coefficient at the current moment according to the temperature change trend uniformity, the constant temperature recovery coefficient, and the temperature delay synchronization factor. When it is determined that there is a raw material switch, obtain the proportional gain correction coefficient at the current moment according to the proportion of the temperature delay synchronization factors less than or equal to the first preset threshold, in combination with the temperature change trend uniformity, the constant temperature recovery coefficient, and the temperature delay synchronization factor. The temperature change trend uniformity, the constant temperature recovery coefficient, and the temperature delay synchronization factor are all negatively correlated with the proportional gain correction coefficient; the proportion of the temperature delay synchronization factors less than or equal to the first preset threshold is positively correlated with the proportional gain correction coefficient.

[0011] Further, the method for controlling the output power of the electric tracing band includes: Map the proportional gain correction coefficient to a preset correction interval, and use the sum value of the mapped proportional gain correction coefficient and the constant 1 as a correction factor; obtain the corrected proportional gain coefficient according to the correction factor and the proportional gain coefficient, and control the output power of the electric tracing band based on the corrected proportional gain coefficient.

[0012] Further, the preset correction interval is [-0.2, 0.2].

[0013] The present invention also proposes an intelligent control system for the output power of an electric tracing band. The system includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of any one of the above-mentioned methods for intelligently controlling the output power of an electric tracing band.

[0014] The present invention has the following beneficial effects: The present invention first obtains temperature data to provide a data basis for subsequent analysis; further, according to the change trend of the temperature data of all monitoring points, the uniformity of the temperature change trend is obtained, which characterizes the degree of uniformity of the temperature change trend and reflects the heating effect of the electric tracing band, providing a basis for adjusting the output power of the electric tracing band in the future; further, the monitoring points are segmented, and according to the change in the number of segments of the monitoring points at adjacent times, the constant temperature recovery coefficient of the pipeline at the current moment is obtained, which quantifies the speed at which the pipeline restores temperature uniformity and assists in adjusting the proportional gain coefficient; further, according to the delayed synchronous change of the temperature data of two adjacent monitoring points, the temperature delay synchronous factor is obtained, which quantifies the intensity of the temperature delay synchronous change between adjacent monitoring points, providing a basis for distinguishing the actual causes of uneven pipeline temperature, determining the most suitable adjustment method, and accurately adjusting the output power; further, according to the distribution of all temperature delay synchronous factors, combined with the uniformity of the temperature change trend and the constant temperature recovery coefficient, the proportional gain correction coefficient at the current moment is obtained, accurately identifying the true causes of uneven temperature, improving the adaptability of the adjustment strategy, and enhancing the accuracy and adaptability of the proportional gain adjustment; finally, the initial proportional gain coefficient at the current moment is adjusted according to the proportional gain correction coefficient to control the output power of the electric tracing band, realizing precise control of the output power of the tracing band, and improving temperature uniformity, response speed and energy efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the drawings required for use in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0016] Figure 1 It is a flowchart of an intelligent control method for the output power of an electric tracing band provided by an embodiment of the present invention; Figure 2 It is a schematic diagram of a constant power type electric tracing provided by an embodiment of the present invention; Figure 3 It is a schematic diagram of a constant power type electric tracing band wound around a pipeline and the distribution of monitoring points provided by an embodiment of the present invention; Figure 4 It is a schematic diagram of the comparison of the segmented monitoring points at adjacent times provided by an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0017] To further elaborate on the technical means and effects adopted by the present invention to achieve the intended invention purpose, the following specifically describes, with reference to the accompanying drawings and preferred embodiments, a method and system for intelligent control of the output power of an electric tracing band according to the present invention, including its specific implementation manner, structure, features, and effects. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. In addition, the specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0018] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs.

[0019] The following specifically describes the specific solution of a method and system for intelligent control of the output power of an electric tracing band provided by the present invention with reference to the accompanying drawings.

[0020] Please refer to Figure 1 , which shows a flowchart of a method for intelligent control of the output power of an electric tracing band provided by an embodiment of the present invention, specifically including: Step S1: Obtain the temperature data of each sampling moment at all monitoring points on the pipeline.

[0021] In chemical production, many media have the characteristics of being corrosive or easy to solidify, such as fuming sulfuric acid, asphalt residue oil, etc. The constant power electric tracing band can effectively prevent equipment such as pipelines, storage tanks, and valves from freezing and blocking in low-temperature environments through continuous and stable heating. For example, in the pipeline insulation of fuming sulfuric acid, the constant power electric tracing band is used to maintain a temperature range of 15 - 18°C, avoiding the solidification and blockage of fuming sulfuric acid.

[0022] Please refer to Figure 2 , which shows a schematic diagram of constant power electric tracing provided by an embodiment of the present invention. Figure 2 shows that the constant power electric tracing includes a conductor, insulation, inner sheath, braiding, and sheath from the inside out.

[0023] And the constant power electric tracing band usually needs to be equipped with a temperature controller to control the temperature. The temperature controller can maintain the pipeline temperature within the set range by adjusting the output power of the electric tracing band according to the set temperature range.

[0024] In an embodiment of the present invention, the constant power electric tracing band is evenly wound around the pipeline in chemical production, and several monitoring points are arranged at equal intervals on the pipeline. Each monitoring point collects the temperature in real time through a temperature sensor. In this solution, each single-pass pipeline corresponds to a constant power electric tracing band. Please refer to Figure 3 , which shows a schematic diagram of the winding of a constant power electric tracing band around a pipeline and the distribution of monitoring points provided by an embodiment of the present invention, Figure 3The way of the constant - power type electric tracing band winding around the pipeline is shown, and the monitoring points are evenly distributed on the pipeline.

[0025] In an embodiment of the present invention, the acquisition frequency is 10 seconds / time, and the temperature data of each sampling moment of all monitoring points on the pipeline are obtained, providing a data basis for subsequent analysis.

[0026] Step S2: According to the change trend of the temperature data of all monitoring points within the first preset neighborhood at the current moment, obtain the temperature change trend uniformity at the current moment; based on the APCA algorithm, divide the temperature data at the same moment, and correspondingly obtain the monitoring point segments; according to the change in the number of monitoring point segments at adjacent moments within the second preset neighborhood at the current moment, obtain the constant - temperature recovery coefficient of the pipeline at the current moment.

[0027] In temperature control, when the difference between the set temperature and the actual temperature of the pipeline is small, but the pipeline temperature is uneven, adjusting the proportional (P) value in the PID controller is a common method. The proportional control part is responsible for adjusting the control output according to the current temperature deviation. Therefore, in this solution, by analyzing the temperature data of each monitoring point on the pipeline, the proportional gain coefficient is adjusted to control the output power of the electric tracing band.

[0028] Since the constant - power type electric tracing band provides a constant heat output and theoretically should produce a uniform heating effect on the entire pipeline, the temperature change trend of all monitoring points reflects the uniformity of pipeline heating. Therefore, according to the change trend of the temperature data of all monitoring points within the first preset neighborhood at the current moment, obtain the temperature change trend uniformity at the current moment, which characterizes the degree of uniformity of the temperature change trend, reflects the heating effect of the electric tracing band, and provides a basis for subsequent adjustment of the output power of the electric tracing band.

[0029] Preferably, in an embodiment of the present invention, considering that the positive or negative sign of the first - order difference value of the temperature data of the monitoring point can reflect the rising or falling trend of the temperature (temperature rising is positive, temperature falling is negative); at the same time, the second - order difference value can also reflect the temperature change trend, which is negative when the temperature rising slows down, the temperature falling speeds up, and the temperature first rises and then falls; and is positive when the temperature rising speeds up, the temperature falling slows down, and the temperature first falls and then rises. Therefore, within the first preset neighborhood, obtain the latest first - order difference value and second - order difference value of the temperature data of each monitoring point, and analyze the change trend of the temperature data with the help of the first - order difference value and the second - order difference value.

[0030] As an example, the first preset neighborhood is the nearest 3 seconds at the current moment, including the temperatures at the current moment t, the t - 1 moment, and the t - 2 moment. For each monitoring point, obtain the first - order difference value , and the second - order difference value , where , and They are the temperatures at the x-th monitoring point at the t-th moment, the (t - 1)-th moment, and the (t - 2)-th moment respectively.

[0031] Considering that when the temperature change trends in most areas of the pipeline are similar at the same moment, there are a large number of non-positive first-order difference values or a large number of non-negative first-order difference values, and the greater the dominant proportion of the signs of the first-order difference values, so according to the dominant proportion of non-positive and non-negative first-order difference values, a same-trend factor is obtained.

[0032] As an example, among the non-positive first-order difference values and non-negative first-order difference values, count the number S1 of non-positive first-order difference values and the number S2 of non-negative first-order difference values, and take the ratio of the maximum value of S1 and S2 to the number of monitoring points as the same-trend factor, that is, take the ratio of the number of the first-order difference values with the largest number to the number of monitoring points as the same-trend factor. The larger the ratio, the greater the dominant proportion of a certain type of first-order difference value, and the stronger the same temperature change trend presented on the pipeline.

[0033] Considering that the temperature changes in the external environments where different positions of the pipeline are located are different, and the pipeline may transport chemicals at different temperatures, which will cause the temperatures at the same moment in different areas of the pipeline to be different, resulting in uneven temperature distribution on the pipeline, so the intensity of the opposite temperature change trend at the same moment is also analyzed; Considering that when the difference between the non-negative first-order difference values and the non-positive first-order difference values is larger, it indicates that the temperature increase degree in the temperature increase area on the pipeline at the same moment is larger, and the temperature decrease degree in the temperature decrease area is larger, and the stronger the opposite degree of the temperature change trend; when the difference between the second-order difference values corresponding to the non-negative first-order difference values and the second-order difference values corresponding to the non-positive first-order difference values is larger, it indicates that the temperature increase trend and the temperature decrease trend in different areas are stronger, and the stronger the opposite degree of the temperature change trend; Based on this, according to the difference between the non-negative first-order difference values and the non-positive first-order difference values, combined with the difference between the second-order difference values corresponding to the non-negative first-order difference values and the second-order difference values corresponding to the non-positive first-order difference values, an opposite-trend factor is obtained; As an example, take the linear normalization value of the difference between the mean value Z2 of all non-negative values and the mean value Z1 of all non-positive values among the latest first-order difference values at the current moment as the first opposite factor; take the difference between the mean value U2 of the second-order difference values corresponding to the non-negative first-order difference values and the mean value U1 of the second-order difference values corresponding to the non-positive first-order difference values, and then take the value after linear normalization as the second opposite factor; Take the product of the first opposite factor and the second opposite factor as the opposite-trend factor.

[0034] Finally, the same-trend factor and the opposite-trend factor are fused to obtain the temperature change trend uniformity at the current moment. From the two perspectives of the same change trend and the opposite change trend of the temperature at the same moment, the change trend of the temperature data is shown, and the uniformity intensity of the temperature change trend on the pipeline is quantified.

[0035] As an example, the ratio of the same-trend factor to the opposite-trend factor is used as the temperature change trend uniformity at the current moment.

[0036] In another embodiment of the present invention, considering that the better the uniform heating effect of the pipeline, the more consistent the temperature change trend and the more similar the current temperatures, while the greater the variance of the temperature data at different monitoring points at the current moment, the stronger the degree of temperature dispersion, which can reflect from the side that the temperature distribution is more uneven and the temperature change trend is more uneven. Therefore, the first opposite factor is used as the numerator, the product of the second opposite factor and the variance of the temperature data is used as the denominator, and the fractional ratio is used as the temperature change trend uniformity.

[0037] Considering that based on the APCA algorithm, the temperature data at the same moment can be automatically divided into several temperature segments according to the similarity, and at the same time, the monitoring points are also divided, and the corresponding monitoring point segments are obtained. The number of monitoring point segments can reflect the unevenness of the temperature of the pipeline; Considering that the change situation of the number of monitoring point segments at adjacent moments reflects the evolution of the uniform temperature distribution of the pipeline, so according to the change of the number of monitoring point segments at adjacent moments within the second preset neighborhood at the current moment, the constant temperature recovery coefficient of the pipeline at the current moment is obtained, the speed of the pipeline to recover temperature uniformity is quantified, and the proportional gain coefficient is assisted to be adjusted to control the output power of the electric tracing band.

[0038] Preferably, in an embodiment of the present invention, the second preset neighborhood includes the nearest 6 acquisition time points (the acquisition time point at the current moment and 5 nearest historical acquisition time points). First, any moment is selected as the target moment for easy analysis one by one; Please refer to Figure 4 , which shows a schematic diagram of the comparison of monitoring point segments at adjacent moments provided by an embodiment of the present invention; Figure 4 It includes the monitoring point segment results at time t1, time t2, and time t3, and t1 to t3 are in the positive time sequence; each horizontal line represents all the monitoring points on the pipeline, the black dots represent the segmentation points, and the numbers are the segmentation serial numbers.

[0039] Considering that when the pipeline shows a gradually uniform temperature, as time changes, the number of monitoring point segments shows a gradual decrease. Some monitoring point segments at the target moment will be merged into one monitoring point segment at the next adjacent moment, as Figure 4The 3rd and 4th segments of t1 in [reference] are merged into 2 segments in t2; the 1st and 2nd segments of t2 are merged into 1 segment in t3; when the effect of segment merging is more obvious, the number of segments where the segments of a single monitoring point intersect with the segments of the monitoring point at the next adjacent moment is less; Based on this, in the segments of the monitoring points at the next adjacent moment of the target moment, obtain the number of segments of the monitoring points that have monitoring point intersections with each segment of the monitoring points at the target moment, and use it as the splitting number of each segment of the monitoring points at the target moment; Take the ratio of the sum value of all splitting numbers corresponding to the target moment to the number of segments of the monitoring points as the splitting degree coefficient at the target moment; Also considering that when the number of segments shows a more obvious downward trend, it reflects that the splitting situation of the segments of the monitoring points is alleviated and the temperature distribution tends to be uniform; at the same time, when the overall characteristic of the splitting degree coefficient is smaller, the temperature distribution is more uniform and the constant temperature recovery situation is better. Therefore, obtain the constant temperature recovery coefficient at the current moment according to the overall characteristic of the splitting degree coefficient and the downward trend intensity of the number of segments of the monitoring points; the overall characteristic of the splitting degree coefficient is negatively correlated with the constant temperature recovery coefficient; the downward trend intensity is positively correlated with the constant temperature recovery coefficient.

[0040] As an example, as Figure 4 shown in [reference], the 1st segment of t1 intersects with the 1st segment of t2, and the splitting number of the 1st segment of t1 is 1, denoted as t1-1 = 1; the 2nd segment of t1 intersects with the 1st and 2nd segments of t2, denoted as t1-2 = 2; by analogy, obtain t1-3 = 1, t1-4 = 1. The sum value of all splitting numbers at the t1 moment is 5, the number of segments of the monitoring points is 4, and the splitting degree coefficient is 5 / 4 = 1.25.

[0041] t2-1 = 1, t2-2 = 1, the sum value of all splitting numbers at the t2 moment is 2, the number of segments of the monitoring points is 2, and the splitting degree coefficient is 1.

[0042] When the pipeline tends to have a uniform temperature, the segments are gradually merged, the splitting degree coefficient approaches 1 (gradually becomes smaller), the constant temperature recovery coefficient is larger, and the change in the number of segments of the monitoring points is reflected from the perspective of the merging of segment splitting.

[0043] In the second preset neighborhood at the current moment, use the least squares method to obtain the fitting line of the number of segments of the monitoring points changing with time, obtain the slope of the fitting line and perform linear normalization to get K, use the difference between 1 and K as the numerator, representing the downward trend intensity of the number of segments of the monitoring points, use the mean value of all splitting degree coefficients as the denominator, representing the overall characteristic of the splitting degree coefficient, and the fractional ratio as the constant temperature recovery coefficient.

[0044] It should be noted that the method of segmenting by the APCA algorithm, fitting a straight line by the least squares method, and obtaining the slope are all well-known technical means to those skilled in the art, and will not be elaborated here.

[0045] In other embodiments of the present invention, the implementer can also directly use the least squares method to obtain the fitting straight line of the number of segments of the monitoring points changing with time, obtain the slope of the fitting straight line, and perform negative correlation mapping on the slope through a negative correlation mapping such as the exponential function exp(-x) with the natural constant e as the base. The mapping result is used as the constant temperature recovery coefficient, where x is the independent variable. The process of analyzing the splitting degree coefficient is omitted, the angle of analyzing the change in the number of segments of the monitoring points is reduced, and a certain amount of accuracy is sacrificed to improve the calculation efficiency, with more emphasis on the correction rate of the output power.

[0046] Step S3: Along the flow direction of the substance in the pipeline, according to the delayed synchronous change of the temperature data in the third preset neighborhood of two adjacent monitoring points at the current moment, obtain the temperature delay synchronous factor of the corresponding two monitoring points at the current moment; according to the distribution of all temperature delay synchronous factors at the current moment, combined with the uniformity of the temperature change trend and the constant temperature recovery coefficient, obtain the proportional gain correction coefficient at the current moment.

[0047] In the process of chemical production, different raw materials or solvents need to be added to the feed pipeline of the chemical reactor in a specific order, or the source of the raw material transported by the pipeline changes, and the temperature of the same raw material changes. Therefore, chemicals with different temperatures may be transported in the pipeline.

[0048] Due to the temperature change caused by the material switch, the temperature of the same monitoring point may change significantly in a short time. That is, during the switch, the new raw material starts to enter the pipeline, and the old raw material has not been completely discharged, which will cause a rapid change in the temperature in the pipeline. This temperature change will automatically and rapidly recover as the raw material or solvent switch is completed. If the pipeline temperature is uneven due to the temperature change in a certain link, the pipeline temperature does not have the characteristic of automatic recovery.

[0049] Considering that different situations require different adjustments to the proportional gain coefficient, it is necessary to distinguish the actual cause of the temperature non-uniformity. The temperature change caused by the raw material switch will cause similar temperature changes to occur one by one at the monitoring points along the flow direction of the substance in the pipeline, showing the characteristic of delayed synchronous change. Therefore, along the flow direction of the substance in the pipeline, according to the delayed synchronous change of the temperature data in the third preset neighborhood of two adjacent monitoring points at the current moment, obtain the temperature delay synchronous factor of the corresponding two monitoring points at the current moment, quantify the intensity of the temperature delay synchronous change between adjacent monitoring points, and provide a basis for distinguishing the actual cause of the pipeline temperature non-uniformity, determining the most appropriate adjustment method, and accurately adjusting the output power.

[0050] Preferably, in an embodiment of the present invention, considering that the Dynamic Time Warping (DTW) algorithm can optimally align two time series with non-linear offsets in time to minimize the overall distance between them, the slope between each pair of matching points can reflect the synchronization situation on the time axis, so as to comparatively analyze the delay synchronization characteristics of two temperature data series; Based on this, two adjacent monitoring points are matched to form a matching group, and the temperature data corresponding to the two monitoring points in the third preset neighborhood at the current moment in each matching group are subjected to DTW matching; According to the slope distribution between the matching data pairs in the DTW matching result of each matching group, the temperature delay synchronization factor of the matching group at the current moment is obtained.

[0051] Preferably, in an embodiment of the present invention, the third preset neighborhood includes the current moment and the nearest 30 historical moments; the temperature data of each monitoring point is matched with the temperature data of the next monitoring point in the medium flow direction; considering that when the slope is less than zero, it indicates that there is a delay in the temperature data of the next monitoring point, and the higher the proportion of negative-slope matches, the more obvious the delay feature. At the same time, the smaller the variance of the slope and the DTW, the more concentrated the slope, the stronger the similarity of the temperature data, and the stronger the temperature delay synchronization; Based on this, for each matching group, according to the variance of the slopes between all matching pairs, the proportion of negative-slope matching pairs, and the DTW distance, the temperature delay synchronization factor of each matching group at the current moment is obtained.

[0052] As an example, for each matching group, the variance of the slopes between all matching pairs is used as the denominator, the DTW distance is negatively correlated and mapped through exp(-x), the product of the mapped value and the proportion of negative-slope matching pairs is used as the numerator, and the linear normalization result of the fractional ratio is used as the temperature delay synchronization factor of the corresponding matching group at the current moment.

[0053] It should be noted that the DTW algorithm is already a well-known technical means for those skilled in the art and will not be elaborated here.

[0054] Considering that the distribution of all temperature delay synchronization factors at the current moment reflects the main inducement of temperature non-uniformity at the current moment, and the temperature change trend uniformity characterizes the consistency intensity of the current temperature change trend of the pipeline in spatial distribution, and the constant temperature recovery coefficient characterizes the intensity of the pipeline's current ability to recover to a constant temperature, so according to the distribution of all temperature delay synchronization factors at the current moment, combined with the temperature change trend uniformity and the constant temperature recovery coefficient, the proportional gain correction coefficient at the current moment is obtained to accurately identify the true inducement of temperature non-uniformity, improve the adaptability of the adjustment strategy, improve the accuracy and adaptability of proportional gain adjustment, and prevent over-adjustment or under-adjustment.

[0055] Preferably, in an embodiment of the present invention, since the change in ambient temperature is relatively slow, when the difference between the set temperature and the actual temperature of the pipeline is small, but the pipeline temperature is uneven, if the pipeline temperature unevenness is caused by the switching of raw materials or solvents, it will recover relatively quickly after the switching is completed. In this case, it is necessary to reduce the proportional gain coefficient to reduce the direct response of the control output to the temperature deviation, that is, to prevent the output power of the electric heat tracing belt from being frequently changed, thereby reducing overshoot and undershoot, which helps to stabilize and evenly distribute the temperature.

[0056] If the pipeline temperature unevenness is caused by the change in ambient temperature, it is necessary to increase the proportional gain coefficient to increase the response speed of the control output to the temperature deviation, thereby accelerating the temperature recovery speed.

[0057] Considering that when there are more large temperature delay synchronization factors, it indicates that the characteristic of the temperature data of adjacent monitoring points on the pipeline showing delayed synchronous change with the medium flow is stronger, and it is more likely to be a raw material switch. Therefore, if the number of temperature delay synchronization factors greater than the first preset threshold at the current moment is greater than the second preset threshold, it is determined that there is a raw material switch; otherwise, it is determined that there is no raw material switch; analyze the distribution of all temperature delay synchronization factors with the help of the first preset threshold and the second preset threshold.

[0058] As an example, the first preset threshold is 0.7. Since the total number of all temperature delay synchronization factors is Set the second preset threshold to , where S4 is the number of monitoring points on the pipeline; is the ceiling function; obtain the number S3 of temperature delay synchronization factors greater than 0.7. When S3 is greater than , it is determined that there is a raw material switch; otherwise, it is determined that there is no raw material switch.

[0059] When it is determined that there is no raw material switch, the smaller the temperature change trend uniformity and the constant temperature recovery coefficient, the weaker the trend of uniform temperature change and the trend of the pipeline to recover temperature uniformity, and the stronger the influence of the environment on temperature unevenness, the more adjustment is needed; at the same time, the smaller the temperature delay synchronization factor, the less likely there is a raw material switch, and the more likely it is caused by the change in ambient temperature resulting in uneven pipeline temperature. Therefore, at this time, a larger proportional gain coefficient is required to increase the response speed of the control output to the temperature deviation, thereby accelerating the temperature recovery speed.

[0060] Based on this, according to the temperature change trend uniformity, the constant temperature recovery coefficient, and the temperature delay synchronization factor, obtain the proportional gain correction coefficient at the current moment; the temperature change trend uniformity, the constant temperature recovery coefficient, and the temperature delay synchronization factor are all negatively correlated with the proportional gain correction coefficient.

[0061] As an example, the product of the temperature change trend uniformity and the constant temperature recovery coefficient at the current moment is used as the independent variable, and after negative correlation mapping through exp(-x), it is used as the first factor; the value obtained by subtracting the average value of the temperature delay synchronization factor from the constant 1 is used as the second factor, and the linear normalization value of the product of the first factor and the second factor is used as the proportional gain correction coefficient.

[0062] When it is determined that there is a raw material switch, it is also necessary to consider the influence of the ambient temperature change during the chemical raw material switch in the pipeline. Considering that the fewer the number of temperature delay synchronization factors less than the first preset threshold, it indicates that fewer monitoring points are affected by the environment and cannot show temperature delay synchronization changes between adjacent monitoring points, and the environmental influence is weaker. A smaller proportional gain coefficient is required to reduce the direct response of the control output to the temperature deviation, that is, to prevent frequent changes in the output power of the electric heat tracing belt, thereby reducing overshoot and undershoot situations and contributing to the stable and uniform distribution of temperature.

[0063] Based on this, according to the proportion of the temperature delay synchronization factors less than or equal to the first preset threshold, combined with the temperature change trend uniformity, the constant temperature recovery coefficient, and the temperature delay synchronization factor, the proportional gain correction coefficient at the current moment is obtained; As an example, the calculation formula of the proportional gain correction coefficient includes: ; where represents the proportional gain correction coefficient; represents the linear normalization function; represents the temperature change trend uniformity; represents the constant temperature recovery coefficient; represents the mean value of the temperature delay synchronization factor; represents the number of temperature delay synchronization factors less than or equal to the first preset threshold; represents the total number of all temperature delay synchronization factors; represents the proportion of the temperature delay synchronization factors less than or equal to the first preset threshold.

[0064] In the calculation formula of the proportional gain correction coefficient, the temperature change trend uniformity and the constant temperature recovery coefficient are fused by multiplication, and is linearly normalized, so that , , are of the same order of magnitude, avoiding a situation where one factor dominates and the influence of other factors is small; through represents the overall characteristics of the temperature delay synchronization factor, the smaller it is, the greater the environmental influence and the greater the proportional gain correction coefficient; The larger it is, the wider the scope of environmental impact, and the larger the proportional gain correction coefficient. The ratio of the temperature delay synchronization factor less than or equal to the first preset threshold is positively correlated with the proportional gain correction coefficient.

[0065] In other embodiments of the present invention, the implementer can also fuse , , by addition or weighted summation to obtain the proportional gain correction coefficient.

[0066] Step S4: Adjust the initial proportional gain coefficient at the current moment to control the output power of the electric tracing band according to the proportional gain correction coefficient.

[0067] After obtaining the adjustment basis by obtaining the proportional gain correction coefficient, the initial proportional gain coefficient at the current moment can be adjusted according to the proportional gain correction coefficient to control the output power of the electric tracing band, realizing precise control of the output power of the electric tracing band and optimizing the temperature control effect.

[0068] Preferably, in an embodiment of the present invention, in order to control the correction range of the proportional gain coefficient, the proportional gain correction coefficient is mapped to a preset correction interval, and the sum value of the mapped proportional gain correction coefficient and the constant 1 is used as the correction factor; As an example, the preset correction interval is [-0.2, 0.2], the corresponding range of the correction factor is [0.8, 1.2], and the correction range of the proportional gain coefficient is 80% to 120%.

[0069] Obtain the corrected proportional gain coefficient according to the correction factor and the proportional gain coefficient, and control the output power of the electric tracing band based on the corrected proportional gain coefficient.

[0070] As an example, the product of the correction factor and the proportional gain coefficient is used as the corrected proportional gain coefficient.

[0071] It should be noted that the initial proportional gain coefficient at the current moment is a preset value, which can be obtained by the tuning method; in other embodiments of the present invention, it can also be obtained by any one or more of empirical preset, trial and error method or response curve method, etc., which will not be elaborated here.

[0072] An embodiment of the present invention uses an adaptive PID controller to intelligently control the output power of the electric tracing band. Among them, the adaptive PID control can adjust the parameters in real time according to the change of the system state, thereby improving the control accuracy and response speed.

[0073] Based on the real-time temperature of all detection points on the pipeline, combined with the corrected proportional gain coefficient after real-time adjustment, use the adaptive PID controller to realize the intelligent control of the output power of the electric tracing band, specifically: (1) By installing temperature sensors, the temperature of each monitoring point on the pipeline surface is monitored in real time, and the temperature signal is transmitted to the control system.

[0074] (2) The intelligent controller automatically adjusts the output power of the electric tracing band according to the temperature data collected by the temperature sensors and the proportion gain coefficient adjusted in real time, in combination with the preset temperature control strategy, to achieve precise temperature control.

[0075] (3) Through the communication module, the intelligent controller can exchange data with other devices to achieve remote monitoring and control.

[0076] Thus, by analyzing the collected data, the temperature control effect is optimized to achieve precise control of the output power of the electric tracing band, reduce energy consumption, and improve the reliability and safety of the electric tracing band.

[0077] An embodiment of the present invention also provides an intelligent control system for the output power of an electric tracing band. The system includes a memory, a processor, and a computer program. The memory is used to store the corresponding computer program, and the processor is used to run the corresponding computer program. When the computer program runs in the processor, it can implement an intelligent control method for the output power of an electric tracing band described in steps S1 - S4.

[0078] In summary, in view of the technical problem that the existing control of the output power of the electric tracing band is inaccurate and affects the constant temperature control effect, the present invention proposes an intelligent control method and system for the output power of the electric tracing band. The present invention first obtains temperature data, further obtains the uniformity of the temperature change trend according to the change trend of the temperature data of all monitoring points, further segments the monitoring points, and obtains the constant temperature recovery coefficient of the pipeline at the current moment according to the change in the number of segments of the monitoring points at adjacent moments. Further, according to the delayed synchronous change of the temperature data of two adjacent monitoring points, in combination with the uniformity of the temperature change trend and the constant temperature recovery coefficient, the proportion gain correction coefficient at the current moment is obtained. Finally, the initial proportion gain coefficient at the current moment is adjusted according to the proportion gain correction coefficient to control the output power of the electric tracing band, achieving precise regulation of the output power of the electric tracing band, and improving the temperature uniformity, response speed, and energy efficiency.

[0079] It should be noted that the above sequence of embodiments of the present invention is only for description and does not represent the advantages or disadvantages of the embodiments. The processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0080] Each embodiment in this specification is described in a progressive manner. The same or similar parts among the embodiments can be referred to each other, and the key points of each embodiment are the differences from other embodiments.

Claims

1. An intelligent control method for output power of an electric heating cable, characterized in that: The method includes: Obtaining temperature data at each sampling moment of all monitoring points on the pipeline; Based on the change trends of the temperature data of all the monitoring points within a first preset neighborhood at the current moment, obtaining the temperature change trend uniformity at the current moment; dividing the temperature data at the same moment based on the APCA algorithm to correspondingly obtain segmented monitoring points; based on the change in the number of segmented monitoring points at adjacent moments within a second preset neighborhood at the current moment, obtaining the constant temperature recovery coefficient of the pipeline at the current moment; Along the flow direction of the substance in the pipeline, based on the delayed synchronous change of the temperature data of two adjacent monitoring points within a third preset neighborhood at the current moment, obtaining the temperature delay synchronous factor of the two corresponding monitoring points at the current moment; based on the distribution of all the temperature delay synchronous factors at the current moment, combining the temperature change trend uniformity and the constant temperature recovery coefficient, obtaining the proportional gain correction coefficient at the current moment; Adjusting the initial proportional gain coefficient at the current moment according to the proportional gain correction coefficient to control the output power of the electric heat tracing band.

2. The intelligent control method for the output power of an electric tracing band according to claim 1, wherein The method for obtaining the temperature change trend uniformity includes: Within the first preset neighborhood, obtaining the latest first-order difference value and second-order difference value of the temperature data of each monitoring point; Based on the dominant proportion situation of the non-positive and non-negative first-order difference values, obtaining the same-trend factor; Based on the difference between the non-negative first-order difference value and the non-positive first-order difference value, combining the difference between the second-order difference value corresponding to the non-negative first-order difference value and the second-order difference value corresponding to the non-positive first-order difference value, obtaining the opposite-trend factor; Fusing the same-trend factor and the opposite-trend factor to obtain the temperature change trend uniformity at the current moment.

3. The intelligent control method for the output power of an electric tracing band according to claim 2, characterized in that, The method for obtaining the same-trend factor includes: Among the non-positive first-order difference values and non-negative first-order difference values, taking the ratio of the number of the first-order difference values with the largest quantity to the number of monitoring points as the same-trend factor.

4. The intelligent control method for the output power of an electric tracing band according to claim 1, characterized in that, The method for obtaining the constant temperature recovery coefficient includes: Selecting any moment as the target moment, within the segmented monitoring points at the adjacent next moment of the target moment, obtaining the number of segmented monitoring points having a monitoring point intersection with each segmented monitoring point of the target moment as the splitting quantity of each segmented monitoring point of the target moment; Taking the ratio of the sum value of all the splitting quantities corresponding to the target moment to the number of segmented monitoring points as the splitting degree coefficient of the target moment; Obtaining the constant temperature recovery coefficient at the current moment according to the overall characteristics of the splitting degree coefficient and the decreasing trend intensity of the number of segmented monitoring points; the overall characteristics of the splitting degree coefficient are negatively correlated with the constant temperature recovery coefficient; the decreasing trend intensity is positively correlated with the constant temperature recovery coefficient.

5. The intelligent control method for the output power of an electric tracing band according to claim 1, characterized in that, The method for obtaining the temperature delay synchronous factor includes: Matching two adjacent monitoring points to form a matching group, and performing DTW matching on the corresponding temperature data of the two monitoring points in each matching group within a third preset neighborhood at the current moment; According to the slope distribution between the matching data pairs in the DTW matching results of each matching group, the temperature delay synchronization factor of the matching group at the current moment is obtained.

6. The intelligent control method for the output power of an electric tracing band according to claim 5, wherein, The method for obtaining the temperature delay synchronization factor of the matching group at the current moment according to the slope distribution between the matching data pairs in the DTW matching results of each matching group includes: For each matching group, the temperature delay synchronization factor of each matching group at the current moment is obtained based on the variance of the slopes between all matching pairs, the proportion of matching pairs with negative slopes, and the DTW distance.

7. The intelligent control method for the output power of an electric tracing band according to claim 1, characterized in that, The method for obtaining the proportional gain correction coefficient includes: If the number of the temperature delay synchronization factors greater than the first preset threshold at the current moment is greater than the second preset threshold, it is determined that there is a raw material switch; otherwise, it is determined that there is no raw material switch; When it is determined that there is no raw material switching, obtaining a proportional gain correction coefficient at the current moment according to the temperature change trend uniformity, the constant temperature recovery coefficient, and the temperature delay synchronization factor; When it is determined that there is a raw material switch, the proportional gain correction coefficient at the current moment is obtained based on the proportion of the temperature delay synchronization factor that is less than or equal to the first preset threshold, combined with the temperature change trend uniformity, the constant temperature recovery coefficient, and the temperature delay synchronization factor; The temperature change trend uniformity, the constant temperature recovery coefficient and the temperature delay synchronization factor are all negatively correlated with the proportional gain correction coefficient; the proportion of the temperature delay synchronization factor that is less than or equal to the first preset threshold is positively correlated with the proportional gain correction coefficient.

8. The intelligent control method for the output power of an electric tracing band according to claim 1, characterized in that The method for controlling the output power of the electric heating tape comprises: The proportional gain correction coefficient is mapped to a preset correction interval, and the sum of the mapped proportional gain correction coefficient and a constant 1 is used as a correction factor; a corrected proportional gain coefficient is obtained according to the correction factor and the proportional gain coefficient, and the output power of the electric heating tape is controlled based on the corrected proportional gain coefficient.

9. The method for intelligently controlling the output power of an electric heating tape according to claim 8, characterized in that: The preset correction interval is [-0.2, 0.2].

10. An intelligent control system for the output power of an electric tracing band, the system comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, the steps of the method for intelligently controlling the output power of an electric heating tape as described in any one of claims 1 to 9 are implemented.

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