SF6 density controller bimetallic strip adaptive matching method based on control strategy

Abstract

This invention discloses an adaptive matching method for bimetallic strips of SF6 density controllers based on control strategies, relating to the field of density controller parameter matching technology. The method includes the following steps: acquiring the pressure signal, Bourdon tube end displacement signal, and bimetallic strip displacement signal of the SF6 density controller within the operating pressure neighborhood; calculating the number of displacement direction changes per unit time based on the displacement signal to obtain the displacement alternation frequency; and selecting a continuous region within the pressure range where the displacement alternation frequency is higher than a preset threshold as the drift focusing segment. This invention extracts the wander amplitude and dwell density of the operating boundary, transforming contact fluctuations into a continuous interval expression, thereby stabilizing the operating determination process. Simultaneously, based on the stable operating boundary interval, the bimetallic strip parameters are matched and adjusted, and the operating pressure distribution is corrected to ensure consistency between temperature compensation and pressure response, improving the operating stability and adaptability of the density controller in changing environments.

Description

Technical Field

[0001] This invention relates to the field of density controller parameter matching technology, and specifically to an adaptive matching method for bimetallic strips of SF6 density controllers based on control strategies. Background Technology

[0002] The SF6 density controller bimetallic strip adaptive matching based on control strategy refers to the coupling relationship between the pressure response of the Bourdon tube and the temperature compensation of the bimetallic strip in the density controller. It involves measuring the tube end displacement of the Bourdon tube under different rated pressures, and the changes in the opening and closing displacement of the bimetallic strip during temperature changes. These two types of displacement data are uniformly collected and quantified, and a corresponding relationship model is established. Based on this, temperature response data of bimetallic strips of different specifications are combined for calculation and analysis. This allows the temperature deformation of the bimetallic strip to compensate for the pressure indication deviation caused by temperature changes in the Bourdon tube. Furthermore, to address displacement response offsets caused by batch differences in the Bourdon tube, a multi-specification bimetallic strip library is constructed and matched one by one. The optimal bimetallic strip combination is automatically selected, achieving matching determination without relying on high or low temperature testing environments. This ensures that the final density controller maintains stable indication accuracy within a range of ±0.02 MPa under temperature variations. Essentially, it embodies an adaptive matching method that uses displacement response data as the core and completes matching relationship calculation and optimal selection through a control strategy.

[0003] The existing technology has the following shortcomings: When the SF6 density controller operates at a critical state where the gas density is close to the action threshold, the Bourdon tube will generate a high-frequency, micro-amplitude reciprocating displacement under the action of small pressure fluctuations, while the bimetallic strip will undergo slow and continuous deformation changes due to the influence of ambient temperature. There is a significant difference in the response speed between the two, which leads to a dynamic superposition deviation during the displacement matching calculation. During the continuous change of this deviation, the matching result will repeatedly cross the action judgment boundary in a short period of time, causing the internal contacts of the density controller to frequently switch between closed and open states, resulting in contact bounce. This bounce state will be identified as a continuous valid signal by the relay protection system, thereby triggering repeated triggering or even false tripping, which seriously affects the operational stability of electrical equipment.

[0004] The information disclosed in the background section is only intended to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0005] The purpose of this invention is to provide an adaptive matching method for bimetallic strips of SF6 density controllers based on control strategies, so as to solve the problems in the background art mentioned above.

[0006] To achieve the above objectives, the present invention provides the following technical solution: an adaptive matching method for bimetallic strips of SF6 density controllers based on control strategies, comprising the following steps: The pressure signal, Bourdon tube end displacement signal, and bimetallic strip displacement signal of the SF6 density controller within the operating pressure range are acquired. The displacement signal is calculated according to the time series to obtain the displacement alternation frequency by calculating the number of displacement direction changes per unit time. A continuous region with a displacement alternation frequency higher than a preset threshold is selected as the drift focusing section within the pressure range. Time delay processing is performed on the displacement signal of the spring tube end in the drift focusing section, and reverse compensation mapping processing is performed on the displacement signal of the bimetallic strip. The displacement difference change rate at the corresponding position is calculated, and the drift duration is determined based on the cumulative change of the displacement difference change rate in the continuous time window to obtain the drift traction strength. By using the drift traction intensity and displacement alternation frequency, the pressure change range corresponding to the action judgment boundary within a preset time window is statistically analyzed, and the maximum offset of the action judgment boundary in the pressure axis direction is calculated to obtain the action boundary drift amplitude. Around the pressure range corresponding to the amplitude of the motion boundary wander, the number of times the motion judgment boundary appears within a unit pressure range is counted to obtain the motion boundary dwell density. The motion judgment boundary is then smoothed according to the motion boundary dwell density distribution to obtain a stable motion boundary range. Based on the stable action boundary range and the action boundary dwell density, bimetallic strip combinations with different temperature response characteristics are selected from the preset bimetallic strip parameter library. By adjusting the thickness parameter, material combination parameter or initial curvature parameter, the temperature compensation displacement and the displacement deviation of the spring tube end are reduced. At the same time, the action pressure distribution is corrected according to the action boundary wander amplitude, thus completing the adaptive matching of the SF6 density controller bimetallic strip.

[0007] Preferably, the process for selecting the drift focusing section is as follows: The pressure signal, Bourdon tube end displacement signal, and bimetallic strip displacement signal of the SF6 density controller within the operating pressure neighborhood are acquired, and a corresponding relationship is formed at the same time point to obtain a data set. Based on the data set, the displacement difference between adjacent sampling times is compared along the time sequence and the direction of change is determined. The number of direction changes is accumulated within a preset time window to form the displacement alternation frequency. The pressure values ​​at corresponding time points are arranged according to the frequency of displacement alternation, and continuous sub-intervals are divided within the pressure interval to form a frequency distribution pattern. Based on the frequency distribution status, a judgment criterion is selected to screen each pressure sub-interval, and the pressure intervals that continuously meet the conditions are extracted as the drift focusing segments.

[0008] Preferably, the minimum displacement change is introduced as a criterion for judgment during the displacement difference comparison process to filter out minor disturbances. The direction change is recorded in an alternating state within the time range, and the number of direction changes is accumulated within a preset time window to obtain the displacement alternation frequency. At the same time, the displacement alternation frequency shows a continuous distribution within the pressure range and forms a corresponding relationship with the pressure sub-range.

[0009] Preferably, the steps for obtaining drift traction strength are as follows: Within the time range corresponding to the drift focusing section, the displacement signal of the Bourdon tube end and the displacement signal of the bimetallic strip are arranged point by point, and the displacement signal of the Bourdon tube end is adjusted backward along the time axis to form a time delay processing. At the same time, the displacement signal of the bimetallic strip is subjected to reverse compensation mapping processing with the displacement value at the current time point as a reference benchmark to construct the displacement combination relationship. Based on the displacement combination relationship, the displacement difference at the corresponding position is obtained along the time axis and the difference change trajectory is formed. The difference change amplitude between adjacent time points is recorded and collected according to time segments. The difference change amplitude is accumulated within the time segment to obtain the cumulative change. The drift duration is formed by extracting continuous time segments based on the distribution of the cumulative change over the time axis, and the drift traction intensity is determined based on the distribution of the cumulative change over this time range and the duration of the drift.

[0010] Preferably, the difference change amplitude is accumulated in chronological order within the time segment, and the time segment covers continuous sampling points and is consistent with the interval corresponding to the time delay processing. At the same time, the time range covering multiple adjacent time segments is extracted from the continuously distributed time segments to form the drift duration span, and the drift traction intensity is determined by combining the distribution state of the accumulated change on the time axis and the duration.

[0011] Preferably, the steps for generating the motion boundary wander amplitude are as follows: Around the time range corresponding to the drift focusing section, the drift traction intensity and displacement alternation frequency are introduced into the pressure signal at the same time point to form a corresponding relationship. A continuous time interval is selected as a preset time window, so that the time window is continuously advanced along the time axis and the displacement direction switching time is marked according to the displacement alternation frequency within the window to determine the action judgment boundary pressure position. Based on the established set of pressure positions of the action judgment boundary, and combined with the distribution of drift traction intensity within the time window, the change of the action judgment boundary in the pressure axis direction is continuously expressed and a pressure position change trajectory is formed. The entire pressure value range covered by the pressure position change trajectory is defined as the pressure change range. For pressure values ​​within the pressure variation range, the distance between the maximum and minimum pressure positions is extracted to form the movement range, and the maximum value of the corresponding movement range is selected as the motion boundary wander amplitude within a continuous time window.

[0012] Preferably, within a continuous time window, the displacement direction switching time is identified based on the displacement alternation frequency, and a set of action judgment boundary pressure positions is formed accordingly. The set of action judgment boundary pressure positions is continuously expressed in combination with the distribution of drift traction intensity within the time window, and a pressure position change trajectory is formed. The entire pressure value range covered by the pressure position change trajectory is defined as the pressure change range. At the same time, the interval distance between the maximum pressure position and the minimum pressure position within the pressure change range is extracted as the basis for the composition of the action boundary drift amplitude.

[0013] Preferably, the steps for obtaining the stable action boundary interval are as follows: Based on the pressure range covered by the motion boundary wander amplitude, the pressure sub-intervals are divided into adjacent pressure sub-intervals along the pressure axis, and the pressure position of the motion judgment boundary is mapped to the corresponding pressure sub-intervals to form a distribution relationship; After establishing a correspondence between the pressure sub-interval and the action judgment boundary pressure position, the action judgment boundary pressure positions from the time window are collected and a set of occurrence records is formed, so that the number of occurrence records corresponds to the number of time windows. The occurrence count within the pressure sub-interval is counted using the occurrence record set to obtain the action boundary dwell density, and a dwell density distribution state is formed along the pressure axis. The statistical results of adjacent pressure sub-intervals are continuously connected and uniformly adjusted in accordance with the residence density distribution, so that the residence density forms a continuous change process on the pressure axis. Multiple adjacent pressure sub-intervals are extracted from the continuous change process to form a continuous pressure range, and this continuous pressure range is defined as the stable action boundary interval.

[0014] Preferably, the occurrence frequency is continuously connected and uniformly adjusted in the order of pressure within adjacent pressure sub-intervals, so that the residence density forms a continuous change process on the pressure axis. Multiple adjacent pressure sub-intervals in the continuous change process are merged to form a continuous pressure range, and the continuous pressure range is defined as the stable action boundary interval.

[0015] Preferably, the adaptive matching steps for bimetallic strips are as follows: Based on the correspondence between the pressure position and the dwell density of the action boundary within the stable action boundary range, a preset bimetallic strip parameter library is introduced and the pressure position is mapped to each group of displacement response records to establish the correspondence. After establishing the correspondence, the bimetallic strip combinations are screened based on the residence density distribution of the action boundary, and the temperature compensation displacement and the Bourdon tube end displacement are arranged in a corresponding arrangement at the same pressure position to obtain a set of candidate combinations. The displacement difference distribution is expanded point by point through the candidate combination set, and the thickness parameter, material combination parameter and initial curvature parameter are adjusted so that the displacement difference forms a continuous change state along the pressure axis. The adjusted bimetallic strip combination is mapped to the pressure range corresponding to the motion boundary wander amplitude, and the motion pressure distribution is continuously corrected to form a new pressure arrangement relationship. Based on the corrected pressure arrangement relationship, a combination of bimetallic strips that satisfies the continuous change of displacement difference and covers the pressure range of the action boundary wander amplitude is selected to complete the adaptive matching of bimetallic strips in the SF6 density controller.

[0016] The technical effects and advantages provided by the present invention in the above technical solution are as follows: This invention introduces a synergistic analysis of displacement alternation frequency and drift traction intensity to continuously characterize the dynamic change process of the action judgment boundary within the pressure neighborhood. This transforms the unstable judgment behavior, which was originally affected by small pressure fluctuations, into an identifiable change range expression. On this basis, the drift amplitude of the action boundary is further extracted and the dwell density is statistically analyzed, thereby transforming the discrete contact switching behavior into a continuous distribution feature. This effectively constrains the fluctuation range of the action boundary, making the contact switching process of the density controller in the critical state tend to be stable and reducing the frequent switching phenomenon caused by short-term fluctuations.

[0017] This invention constructs a bimetallic strip parameter matching path based on the stable action boundary interval and the action boundary residence density. By screening and adjusting the temperature response characteristics in a preset bimetallic strip parameter library, the temperature compensation displacement gradually matches the displacement change of the Bourdon tube end within the pressure range. At the same time, the action pressure distribution is continuously corrected by combining the action boundary wander amplitude. This allows the matched bimetallic strip to maintain the consistency of the action judgment boundary under temperature change conditions, thereby improving the stability of the action output during the overall operation of the density controller and enhancing its adaptability to environmental changes. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0019] Figure 1 This is a flowchart of the SF6 density controller bimetallic strip adaptive matching method based on control strategy according to the present invention. Detailed Implementation

[0020] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, they are provided so that the description of this disclosure will be more complete and fully convey the concept of the exemplary embodiments to those skilled in the art.

[0021] This invention provides, for example Figure 1 The SF6 density controller bimetallic strip adaptive matching method shown includes the following steps: The pressure signal, Bourdon tube end displacement signal, and bimetallic strip displacement signal of the SF6 density controller within the operating pressure range are acquired. The displacement signal is calculated according to the time series to obtain the displacement alternation frequency by calculating the number of displacement direction changes per unit time. A continuous region with a displacement alternation frequency higher than a preset threshold is selected as the drift focusing section within the pressure range. To understand the dynamic changes of the SF6 density controller within its operating pressure range, pressure signals, Bourdon tube end displacement signals, and bimetallic strip displacement signals are synchronously acquired and correlated. Displacement change features are then extracted under a unified time reference to form an identification path for the drift focusing region. The specific steps are as follows: When the SF6 density controller operates to the stage close to the operating pressure, the pressure signal is continuously recorded according to the preset sampling period. The sampling period can be set according to the signal change rate, for example, a millisecond time interval can be selected. At each sampling moment, the corresponding Bourdon tube end displacement signal and bimetallic strip displacement signal are synchronously acquired, so that the pressure value, Bourdon tube end displacement position and bimetallic strip displacement position form a corresponding relationship at the same time point.

[0022] As time progresses, the pressure signal gradually changes within the neighborhood of the action pressure, and the corresponding displacement signal of the Bourdon tube end forms a continuous offset trajectory in space. The bimetallic strip displacement signal forms another change trajectory on the same time axis. The three types of signals are arranged point by point on the time axis to form a complete data set. Each data point contains a time marker, pressure value, and two types of displacement position values, so that subsequent displacement change analysis is based on a unified time reference.

[0023] In the dataset, the displacement signals of the Bourdon tube end and the bimetallic strip are read point by point in chronological order. The displacement difference between two adjacent sampling times is compared. When the displacement difference exceeds the preset minimum displacement change, it is determined to be a positive change. When the displacement difference is lower than the opposite direction of the minimum displacement change, it is determined to be a negative change. The minimum displacement change is used to filter out small disturbances. For example, the displacement amount that matches the sensing resolution can be selected as the judgment benchmark.

[0024] Throughout the entire time span, each directional change is recorded sequentially to form a directional change sequence. As the number of sampling points continues to increase, positive and negative changes alternate on the time axis. The number of directional changes occurring within a preset time window is accumulated and counted. The length of the time window can be set according to the sampling period, for example, it can cover several consecutive sampling points, so that each time window corresponds to a clear displacement alternation frequency value.

[0025] The displacement alternation frequency corresponding to each time window is rearranged according to the pressure value at the corresponding time point, so that each pressure value interval is associated with the corresponding displacement alternation frequency distribution. In this arrangement process, the pressure range is divided into multiple continuous sub-intervals, and the width of each sub-interval is set according to the pressure change resolution requirements. For example, it can be divided according to a fixed pressure interval. The displacement alternation frequency within the same pressure sub-interval is uniformly collected, thereby forming a frequency distribution state along the pressure axis.

[0026] As the pressure range gradually expands, it can be observed that the frequency of displacement alternation in some adjacent pressure sub-ranges is continuously distributed. This continuous region is represented as a range segment in the pressure dimension and corresponds to the frequency data in multiple continuous time windows in the time dimension, thereby establishing a mapping relationship between the pressure range and the frequency of displacement alternation.

[0027] Based on the relationship between pressure range and displacement alternation frequency distribution, a judgment criterion is selected to screen the displacement alternation frequency. This judgment criterion can be set according to historical operating data or statistical results. For example, the average level of displacement alternation frequency can be selected and appropriately adjusted based on it.

[0028] The displacement alternation frequency within each pressure sub-interval is compared one by one. When the displacement alternation frequency within multiple consecutive pressure sub-intervals meets the judgment criterion, the entire consecutive pressure sub-interval is extracted to form a continuous segment. This segment corresponds to multiple consecutive time windows in the time dimension and covers a continuous range in the pressure dimension. Furthermore, the displacement direction changes continuously alternate within the entire segment. This constructs a region that simultaneously possesses temporal continuity and pressure interval continuity. This region is defined as the drift focusing segment, which is used to limit the processing range of subsequent displacement difference change analysis and action boundary recognition.

[0029] Time delay processing is performed on the displacement signal of the spring tube end in the drift focusing section, and reverse compensation mapping processing is performed on the displacement signal of the bimetallic strip. The displacement difference change rate at the corresponding position is calculated, and the drift duration is determined based on the cumulative change of the displacement difference change rate in the continuous time window to obtain the drift traction strength. Based on the time response difference between the displacement signal at the end of the Bourdon tube and the displacement signal of the bimetallic strip within the drift focusing section, the correspondence between the two types of displacements on the same time axis is reconstructed. Then, the characteristics of displacement difference variation and its temporal duration are extracted to obtain the drift traction strength. The specific steps are as follows: Within the time range corresponding to the drift focusing section, the displacement signal of the Bourdon tube end and the displacement signal of the bimetallic strip are arranged point by point according to the original sampling order, so that each sampling moment corresponds to a set of displacement values. While maintaining this correspondence, the Bourdon tube end displacement signal is adjusted backward along the time axis by a certain number of sampling intervals. The sampling interval is selected according to the time length corresponding to the previous sampling period and is consistent with the lag state of the Bourdon tube end displacement response relative to the bimetallic strip displacement response, so that the adjusted Bourdon tube end displacement signal forms a new correspondence with the bimetallic strip displacement signal in time position.

[0030] After the time and position adjustment is completed, the bimetallic strip displacement signal is subjected to reverse compensation mapping processing with the displacement value corresponding to the current time point as the reference benchmark. That is, at the same time point, the change direction of the bimetallic strip displacement signal relative to the reference benchmark is expressed in reverse, so that its change trend is opposite to the change trend of the Bourdon tube end displacement signal after time delay. Thus, at each sampling moment, a set of displacement combinations after time delay processing and reverse compensation mapping processing is constructed, so that the two types of displacement signals have a corresponding state that can be directly compared at the same time point.

[0031] In the displacement combination relationship that has completed time delay processing and reverse compensation mapping processing, the displacement signal of the Bourdon tube end and the displacement signal of the bimetallic strip corresponding to each sampling moment are read point by point along the time axis, and the displacement difference between the two is obtained at the same time point. The displacement difference is arranged continuously in time order to form a difference change trajectory. As the sampling time progresses, the displacement difference between adjacent time points shows a continuous change state. This change is manifested as alternating increase and decrease in the time dimension and as a continuous change in the difference amplitude in the spatial numerical dimension. In this process, the difference change amplitude between adjacent time points is recorded point by point and collected according to a fixed time segment. This time segment covers multiple continuous sampling points and is consistent with the time interval after the aforementioned time delay adjustment, so that each time segment contains a complete displacement difference change process.

[0032] Within each time interval, all difference changes are accumulated in chronological order, so that the difference changes distributed at different sampling points are integrated into the overall change within the time interval, thus forming a cumulative expression of the displacement difference change rate within the time interval, expanding the displacement difference change from a single-point change to a continuous change description within a time range.

[0033] After obtaining the cumulative changes for each time segment, the time segments are arranged sequentially in chronological order, so that the relationship between changes in different time segments forms a continuously unfolding distribution on the time axis. In this distribution, the cumulative changes in some adjacent time segments remain continuous over time. This continuity reflects the characteristic that the displacement difference changes persist within a certain time range. These continuously distributed time segments are extracted as a whole to form a time range covering multiple adjacent time segments, and this time range is defined as the drift duration.

[0034] Within the drift duration, the distribution of cumulative changes on the time axis is correlated with the corresponding time range, so that the continuity of displacement difference changes in the time dimension and the cumulative changes in the numerical dimension are reflected simultaneously. The drift traction intensity is determined based on the density of the cumulative changes within the time range and the duration of the change. This allows the drift traction intensity to reflect both the continuity and accumulation of displacement difference changes, providing a continuous and correlated descriptive basis for subsequent action boundary change analysis.

[0035] To fully understand the specific implementation of this process, the following example will further illustrate it in detail: Suppose a continuous time range is selected within the drift focusing section, with a corresponding sampling period of 10 milliseconds. A total of 50 continuous sampling points are acquired within this time range. At a certain sampling moment, the displacement signal of the Bourdon tube end is 0.120 mm and the displacement signal of the bimetallic strip is 0.085 mm. Then, the displacement signal of the Bourdon tube end is adjusted backward by 2 sampling intervals along the time axis, that is, delayed by 20 milliseconds. At this time, the displacement value of the original first sampling point corresponds to the third sampling position.

[0036] After completing the time delay processing, the bimetallic strip displacement signal is subjected to reverse compensation mapping processing with the current sampling point displacement value as a reference. For example, if the bimetallic strip displacement changes from 0.085 mm to 0.088 mm at a certain moment, it is reversed to change from 0.085 mm to 0.082 mm, so that its change direction is opposite to the change direction of the delayed Bourdon tube end displacement. Then, the displacement difference between the two types of displacement signals is obtained at the same time point. For example, if the delayed Bourdon tube end displacement is 0.135 mm at the 10th sampling point, the corresponding reverse-compensated bimetallic strip displacement is 0.080 mm, so the displacement difference is 0.055 mm. At the 11th sampling point, the corresponding difference becomes 0.060 mm, so the difference change amplitude between adjacent sampling points is 0.005 mm. The difference change amplitude of each sampling point is recorded sequentially along the time axis, and the difference change amplitude within the interval is accumulated by taking 10 consecutive sampling points as a time interval.

[0037] For example, if the cumulative change in a certain time interval is 0.048 mm, and the cumulative change in the next time interval is 0.052 mm, when the cumulative changes in multiple consecutive time intervals remain within a similar range and are continuously distributed on the time axis, these time intervals are extracted as a whole to form the drift duration span. For example, five consecutive time intervals correspond to a total duration of 500 milliseconds. Within this drift duration span, the cumulative changes are arranged in chronological order and expressed in conjunction with the duration. For example, if the cumulative change gradually increases from 0.048 mm to 0.060 mm within 500 milliseconds, then this change process and the corresponding time span are jointly characterized as the drift traction intensity. This traction intensity can simultaneously reflect the temporal continuity and numerical accumulation of the displacement difference change, thus providing a continuous and quantitative basis for subsequent action boundary analysis.

[0038] By using the drift traction intensity and displacement alternation frequency, the pressure change range corresponding to the action judgment boundary within a preset time window is statistically analyzed, and the maximum offset of the action judgment boundary in the pressure axis direction is calculated to obtain the action boundary drift amplitude. Based on the drift traction intensity and displacement alternation frequency already acquired within the drift focusing section, the change process of the action judgment boundary in the time and pressure dimensions is described. The range of pressure change and the boundary position change along the pressure axis are extracted within a continuous time range to obtain the action boundary drift amplitude. The specific steps are as follows: Within the time range corresponding to the drift focusing section, the drift traction intensity is expanded point by point along the sampling sequence, and the corresponding displacement alternation frequency and pressure signal are introduced at the same time point, so that each sampling moment simultaneously has three types of information: drift traction intensity, displacement alternation frequency, and pressure value. Within this time range, a continuous time interval is selected as a preset time window. This time window covers a fixed number of continuous sampling points and is continuously advanced along the time axis in a point-by-point moving manner, so that there is a partial overlap between adjacent time windows.

[0039] Within each time window, the corresponding pressure values ​​are arranged in chronological order to form a pressure change trajectory. At the same time, based on the change in the frequency of displacement alternation between adjacent time points, the moment when the displacement direction changes is marked, and the pressure position corresponding to the moment of change is defined as the action judgment boundary, so that the action judgment boundary forms a set of pressure positions that change with time within the time window.

[0040] Within each preset time window, the change process of the action judgment boundary in the pressure axis direction is continuously expressed by combining the set of pressure positions of the identified action judgment boundary with the distribution of drift traction intensity within that time range. As time progresses within the window, the pressure position corresponding to the action judgment boundary changes continuously between different sampling times. This change is manifested as a positional shift on the pressure axis and a continuous distribution on the time axis. The continuous distribution of drift traction intensity within the same time window makes this shift process a continuous correlation in time.

[0041] The pressure positions corresponding to all action judgment boundaries within the time window are arranged sequentially according to time to form a complete pressure position change trajectory. The entire pressure value range covered by this trajectory is defined as the pressure change range corresponding to the time window, so that the action judgment boundary within the time window is expanded from a single pressure point to a continuous pressure range that changes with time.

[0042] After obtaining the corresponding pressure change range in each preset time window, the pressure change range in each time window is uniformly organized along the pressure axis. The maximum pressure position and minimum pressure position in each time window are extracted, and the distance between the two on the pressure axis is taken as the movement range of the action judgment boundary in that time window.

[0043] As the time window advances continuously along the time axis, each time window corresponds to a movement range value. The movement ranges corresponding to all time windows are arranged in chronological order to form a distribution of the movement change of the action judgment boundary within the continuous time window. The movement range with the largest value in this distribution is selected as the final result and defined as the action boundary wander amplitude. This wander amplitude can reflect the overall change of the action judgment boundary in the pressure axis direction under the combined action of drift traction intensity and displacement alternation frequency, thus providing a clear basis for subsequent stable interval identification and matching relationship adjustment.

[0044] Around the pressure range corresponding to the amplitude of the motion boundary wander, the number of times the motion judgment boundary appears within a unit pressure range is counted to obtain the motion boundary dwell density. The motion judgment boundary is then smoothed according to the motion boundary dwell density distribution to obtain a stable motion boundary range. Around the pressure range corresponding to the amplitude of the motion boundary wander, the distribution of the motion judgment boundary on the pressure axis is refined, and dwell features are extracted in the pressure dimension. Based on this, the motion judgment boundary is continuously adjusted to obtain a stable motion boundary range. The specific steps are as follows: Within the pressure range covered by the determined action boundary wander amplitude, the continuous pressure range is divided along the pressure axis according to fixed pressure intervals, decomposing it into multiple adjacent pressure sub-ranges. Each pressure sub-range has a clear starting pressure position and ending pressure position, and the pressure sub-ranges are connected end to end to form a complete coverage. During the division process, the width of the pressure sub-range is consistent with the resolution of the previous pressure sampling, for example, it is divided according to the smallest resolution unit of a single pressure change record, so that each pressure sub-range can correspond to a specific pressure sampling position.

[0045] After the division is completed, the action judgment boundary pressure positions extracted in each time window in the previous stage are mapped one by one to the corresponding pressure sub-intervals, so that each pressure sub-interval is associated with a set of boundary position records from different time windows, thereby establishing a correspondence between the action judgment boundary distribution and the pressure sub-intervals on the pressure axis.

[0046] After completing the mapping relationship between the pressure sub-intervals and the action judgment boundary pressure positions, the action judgment boundary pressure positions from each time window are collected according to their respective pressure sub-intervals. As the time window progresses continuously along the time axis, each time window generates a corresponding action judgment boundary pressure position. These pressure positions appear repeatedly in multiple time windows and are distributed in different pressure sub-intervals. These position records are accumulated one by one into the corresponding pressure sub-interval, so that a complete set of occurrence records is formed in each pressure sub-interval.

[0047] During the data collection process, the frequency of occurrence within each pressure sub-interval is kept in correspondence with the number of time windows involved in the statistics. That is, the statistics are conducted under the same time range or the same number of time windows, so that the frequency of occurrence between different pressure sub-intervals has a unified time benchmark, thereby making the subsequent action boundary residence density comparable between different pressure intervals.

[0048] Based on the collected results, the occurrence records in each pressure sub-interval are counted, so that each pressure sub-interval corresponds to a specific occurrence value, and this occurrence value is used as the expression form of action boundary dwell density. As all pressure sub-intervals are statistically analyzed, the dwell density distribution along the pressure axis can be obtained. In this distribution, the occurrence counts between adjacent pressure sub-intervals form a continuous variation relationship. The occurrence counts in multiple adjacent pressure sub-intervals form a continuous distribution segment on the pressure axis. This segment reflects the repetitive occurrence of the action judgment boundary within the pressure range, thus forming a continuous distribution structure of action boundary dwell density in the pressure dimension.

[0049] After obtaining the residence density distribution at the action boundary, the occurrence frequency corresponding to each pressure sub-interval is arranged according to the pressure order, so that the residence density on the entire pressure interval forms a continuously unfolded distribution. In this distribution, the numerical changes between adjacent pressure sub-intervals may have local fluctuations. The occurrence frequency in adjacent pressure sub-intervals is continuously connected according to the pressure order, and the statistical results of adjacent pressure sub-intervals are uniformly adjusted to keep the change relationship between adjacent intervals in a continuous transition state. This makes the originally discrete residence density form a continuous change process on the pressure axis and reduces the impact of short-term changes in individual time windows on the overall distribution.

[0050] After completing the continuous adjustment of the residence density distribution, the region where the residence density maintains a continuous distribution on the pressure axis is extracted. The pressure ranges in which the frequency of occurrence in multiple adjacent pressure sub-intervals maintains a continuous relationship are merged, so that this range forms a continuous interval on the pressure axis. Each pressure sub-interval in this continuous interval corresponds to the action judgment boundary position records in multiple time windows. This continuous pressure range is defined as the stable action boundary interval, so that this interval can reflect the concentrated distribution position of the action judgment boundary on the pressure axis and form a correspondence with the pressure range corresponding to the action boundary wander amplitude in the previous stage, thereby providing a stable and continuous pressure reference range for subsequent matching relationship adjustments.

[0051] To fully understand the specific implementation of this process, the following example illustrates it in more detail: Assume the pressure range corresponding to the action boundary shift amplitude is 5.80MPa to 6.00MPa. This pressure range is divided into 20 continuous pressure sub-intervals at fixed intervals of 0.01MPa, such as 5.80-5.81MPa, 5.81-5.82MPa, and so on up to 5.99-6.00MPa. A total of 200 action judgment boundary pressure positions are extracted in the preceding 10 consecutive time windows. For example, the pressure positions appear 18 times near 5.86MPa, 22 times near 5.87MPa, 25 times near 5.88MPa, 27 times near 5.89MPa, 26 times near 5.90MPa, and 24 times near 5.91MPa. The remaining intervals appear between 5 and 15 times. After classifying these pressure positions into their corresponding pressure sub-intervals, the occurrence count of each sub-interval can be obtained.

[0052] Using the total number of time windows as a unified benchmark, the frequency of occurrence directly reflects the residence density distribution, forming a high-density segment that continuously varies from 5.86 MPa to 5.91 MPa on the pressure axis. This distribution is then continuously connected; for example, the statistical results of adjacent intervals are arranged sequentially, and the numerical changes within the 5.88 MPa to 5.90 MPa interval are adjusted from 25, 27, 26 to 26, 27, 26, creating a continuous transition between adjacent intervals. After this adjustment, pressure sub-intervals with more than 20 occurrences and continuous distribution are merged. For example, multiple sub-intervals within the 5.87 MPa to 5.91 MPa range are integrated into a single continuous pressure interval, which is then defined as the stable action boundary interval. This interval reflects the concentrated distribution of the action judgment boundary on the pressure axis, thus providing a clear pressure range basis for subsequent matching.

[0053] Based on the stable action boundary range and the action boundary dwell density, bimetallic strip combinations with different temperature response characteristics are selected from the preset bimetallic strip parameter library. By adjusting the thickness parameter, material combination parameter or initial curvature parameter, the temperature compensation displacement and the displacement deviation of the spring tube end are reduced. At the same time, the action pressure distribution is corrected according to the action boundary wander amplitude to complete the adaptive matching of the SF6 density controller bimetallic strip. The compensation behavior of the bimetallic strip under temperature variation conditions is refined by focusing on the stable action boundary range and the action boundary dwell density. Furthermore, the action pressure distribution is corrected by incorporating the action boundary wander amplitude, thereby achieving adaptive matching of the bimetallic strip in the SF6 density controller. The specific steps are as follows: Within the stable action boundary range, the pressure positions within the range are expanded point by point according to the pressure axis sequence, and each pressure position is made to correspond one-to-one with the corresponding action boundary residence density. Based on this, a preset bimetallic strip parameter library is introduced. This parameter library contains multiple sets of displacement response records corresponding to bimetallic strip combinations. Each set of displacement response records corresponds to a set of determined temperature change conditions, and a temperature-compensated displacement change trajectory is formed under the same pressure position.

[0054] The pressure positions within the stable action boundary interval are mapped point by point to each set of displacement response records in the parameter library, so that each set of bimetallic strips can form a complete temperature-compensated displacement distribution within the pressure range, thereby establishing a unified correspondence between the stable action boundary interval, the action boundary residence density and the bimetallic strip parameter library.

[0055] After the correspondence is established, based on the distribution of the dwell density at the action boundary within the stable action boundary range, each group of bimetallic strip combinations in the parameter library is screened one by one. Within the pressure range of continuous dwell density distribution, the temperature compensation displacement corresponding to each group of bimetallic strip combinations is read point by point, and arranged in correspondence with the change of the displacement at the end of the Bourdon tube at the same pressure position, so that the two types of displacements form a direct comparison relationship at the same pressure position.

[0056] As the pressure position advances point by point, the displacement changes of each bimetallic strip combination at the continuous pressure position are continuously unfolded, so that the combination that maintains a continuous response relationship at multiple adjacent pressure positions is retained, thus forming a set of candidate bimetallic strip combinations that are consistent with the distribution state of the stable action boundary interval.

[0057] After the candidate bimetallic strip combination set is formed, the displacement response process of each candidate combination within the stable action boundary range is unfolded point by point, so that the temperature compensation displacement and the displacement of the spring tube end form a difference distribution at the corresponding pressure position. In this difference distribution, the displacement difference change state corresponding to each pressure position is recorded sequentially along the pressure axis, and the change relationship of the difference change between adjacent pressure positions is continuously observed. On this basis, the thickness parameter of the bimetallic strip combination is gradually adjusted so that the temperature compensation displacement changes accordingly within the pressure range. At the same time, the material combination parameters are reconfigured so that the displacement response forms a new change path under different temperature conditions. Furthermore, the initial curvature parameter is corrected so that the overall displacement response shifts position on the pressure axis.

[0058] During the above parameter adjustment process, the displacement difference is made to continuously decrease along the pressure axis point by point within the stable action boundary range, and this continuous decrease is used as the basis for determining whether the parameter adjustment is complete.

[0059] After parameter adjustment, the adjusted bimetallic strip assembly is remapped to the pressure range corresponding to the amplitude of the motion boundary wander, so that the adjusted temperature compensation displacement forms a new distribution state within this pressure range. In this distribution state, the adjusted motion pressure position is arranged point by point with the original motion pressure position, and the motion pressure distribution is continuously corrected along the pressure axis, so that the corrected motion pressure position forms a continuous arrangement relationship throughout the entire pressure range. At the same time, this arrangement relationship covers the stable motion boundary interval, so that the motion judgment boundary maintains a continuous distribution state within this pressure range, thereby making the motion pressure distribution on the pressure axis form a distribution structure consistent with the stable motion boundary interval.

[0060] After completing the action pressure distribution correction, the bimetallic strip combination that satisfies the requirement that the displacement difference continuously decreases within the stable action boundary range and maintains a continuous distribution within the pressure range corresponding to the action boundary wander amplitude is determined as the final matching result. This ensures that the temperature compensation displacement and the spring tube end displacement of this combination form a continuous correspondence at the corresponding pressure position within the stable action boundary range and maintain a consistent distribution throughout the entire action pressure range. This completes the adaptive matching of the bimetallic strips of the SF6 density controller, enabling the matching result to maintain a stable position of the action judgment boundary on the pressure axis under temperature change conditions, thereby ensuring the consistency of the action output during the operation of the density controller.

[0061] This invention introduces a synergistic analysis of displacement alternation frequency and drift traction intensity to continuously characterize the dynamic change process of the action judgment boundary within the pressure neighborhood. This transforms the unstable judgment behavior, which was originally affected by small pressure fluctuations, into an identifiable change range expression. On this basis, the drift amplitude of the action boundary is further extracted and the dwell density is statistically analyzed, thereby transforming the discrete contact switching behavior into a continuous distribution feature. This effectively constrains the fluctuation range of the action boundary, making the contact switching process of the density controller in the critical state tend to be stable and reducing the frequent switching phenomenon caused by short-term fluctuations.

[0062] This invention constructs a bimetallic strip parameter matching path based on the stable action boundary interval and the action boundary residence density. By screening and adjusting the temperature response characteristics in a preset bimetallic strip parameter library, the temperature compensation displacement gradually matches the displacement change of the Bourdon tube end within the pressure range. At the same time, the action pressure distribution is continuously corrected by combining the action boundary wander amplitude. This allows the matched bimetallic strip to maintain the consistency of the action judgment boundary under temperature change conditions, thereby improving the stability of the action output during the overall operation of the density controller and enhancing its adaptability to environmental changes.

[0063] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. An adaptive matching method for bimetallic strips in an SF6 density controller based on a control strategy, characterized in that, Includes the following steps: The pressure signal, Bourdon tube end displacement signal, and bimetallic strip displacement signal of the SF6 density controller within the operating pressure range are acquired. The displacement signal is calculated according to the time series to obtain the displacement alternation frequency by calculating the number of displacement direction changes per unit time. A continuous region with a displacement alternation frequency higher than a preset threshold is selected as the drift focusing section within the pressure range. Time delay processing is performed on the displacement signal of the spring tube end in the drift focusing section, and reverse compensation mapping processing is performed on the displacement signal of the bimetallic strip. The displacement difference change rate at the corresponding position is calculated, and the drift duration is determined based on the cumulative change of the displacement difference change rate in the continuous time window to obtain the drift traction strength. By using the drift traction intensity and displacement alternation frequency, the pressure change range corresponding to the action judgment boundary within a preset time window is statistically analyzed, and the maximum offset of the action judgment boundary in the pressure axis direction is calculated to obtain the action boundary drift amplitude. Around the pressure range corresponding to the amplitude of the motion boundary wander, the number of times the motion judgment boundary appears within a unit pressure range is counted to obtain the motion boundary dwell density. The motion judgment boundary is then smoothed according to the motion boundary dwell density distribution to obtain a stable motion boundary range. Based on the stable action boundary range and the action boundary dwell density, bimetallic strip combinations with different temperature response characteristics are selected from the preset bimetallic strip parameter library. By adjusting the thickness parameter, material combination parameter or initial curvature parameter, the temperature compensation displacement and the displacement deviation of the spring tube end are reduced. At the same time, the action pressure distribution is corrected according to the action boundary wander amplitude.

2. The SF6 density controller bimetallic strip adaptive matching method based on control strategy according to claim 1, characterized in that, The process for selecting the drift focusing section is as follows: The pressure signal, Bourdon tube end displacement signal, and bimetallic strip displacement signal of the SF6 density controller within the operating pressure neighborhood are acquired, and a corresponding relationship is formed at the same time point to obtain a data set. Based on the data set, the displacement difference between adjacent sampling times is compared along the time sequence and the direction of change is determined. The number of direction changes is accumulated within a preset time window to form the displacement alternation frequency. The pressure values ​​at corresponding time points are arranged according to the frequency of displacement alternation, and continuous sub-intervals are divided within the pressure interval to form a frequency distribution pattern. Based on the frequency distribution status, a judgment criterion is selected to screen each pressure sub-interval, and the pressure intervals that continuously meet the conditions are extracted as the drift focusing segments.

3. The SF6 density controller bimetallic strip adaptive matching method based on control strategy according to claim 2, characterized in that, In the process of comparing displacement differences, the minimum displacement change is introduced as the judgment criterion to filter out minor disturbances. The direction change is recorded in an alternating state within the time range, and the number of direction changes is accumulated within a preset time window to obtain the displacement alternation frequency. At the same time, the displacement alternation frequency shows a continuous distribution within the pressure range and forms a corresponding relationship with the pressure sub-range.

4. The SF6 density controller bimetallic strip adaptive matching method based on control strategy according to claim 2, characterized in that, The steps to obtain drift traction strength are as follows: Within the time range corresponding to the drift focusing section, the displacement signal of the Bourdon tube end and the displacement signal of the bimetallic strip are arranged point by point, and the displacement signal of the Bourdon tube end is adjusted backward along the time axis to form a time delay processing. At the same time, the displacement signal of the bimetallic strip is subjected to reverse compensation mapping processing with the displacement value at the current time point as a reference benchmark to construct the displacement combination relationship. Based on the displacement combination relationship, the displacement difference at the corresponding position is obtained along the time axis and the difference change trajectory is formed. The difference change amplitude between adjacent time points is recorded and collected according to time segments. The difference change amplitude is accumulated within the time segment to obtain the cumulative change. The drift duration is formed by extracting continuous time segments based on the distribution of the cumulative change over the time axis, and the drift traction intensity is determined based on the distribution of the cumulative change over this time range and the duration of the drift.

5. The SF6 density controller bimetallic strip adaptive matching method based on control strategy according to claim 4, characterized in that, Within the time interval, the difference change amplitude is accumulated in chronological order, and the time interval is made to cover continuous sampling points and consistent with the interval corresponding to the time delay processing. At the same time, the time range covering multiple adjacent time intervals is extracted from the continuously distributed time intervals to form the drift duration span. The drift traction intensity is determined by combining the distribution of the accumulated change on the time axis and the duration.

6. The SF6 density controller bimetallic strip adaptive matching method based on control strategy according to claim 4, characterized in that, The steps for generating the motion boundary shift amplitude are as follows: Around the time range corresponding to the drift focusing section, the drift traction intensity and displacement alternation frequency are introduced into the pressure signal at the same time point to form a corresponding relationship. A continuous time interval is selected as a preset time window, so that the time window is continuously advanced along the time axis and the displacement direction switching time is marked according to the displacement alternation frequency within the window to determine the action judgment boundary pressure position. Based on the established set of pressure positions of the action judgment boundary, and combined with the distribution of drift traction intensity within the time window, the change of the action judgment boundary in the pressure axis direction is continuously expressed and a pressure position change trajectory is formed. The entire pressure value range covered by the pressure position change trajectory is defined as the pressure change range. For pressure values ​​within the pressure variation range, the distance between the maximum and minimum pressure positions is extracted to form the movement range, and the maximum value of the corresponding movement range is selected as the motion boundary wander amplitude within a continuous time window.

7. The SF6 density controller bimetallic strip adaptive matching method based on control strategy according to claim 6, characterized in that, Within a continuous time window, the displacement direction switching time is identified based on the frequency of displacement alternation, and a set of action judgment boundary pressure positions is formed accordingly. The set of action judgment boundary pressure positions is continuously expressed by combining the distribution of drift traction intensity within the time window, and a pressure position change trajectory is formed. The entire pressure value range covered by the pressure position change trajectory is defined as the pressure change range. At the same time, the interval between the maximum pressure position and the minimum pressure position within the pressure change range is extracted as the basis for the composition of the action boundary drift amplitude.

8. The SF6 density controller bimetallic strip adaptive matching method based on control strategy according to claim 6, characterized in that, The steps to obtain the stable action boundary interval are as follows: Based on the pressure range covered by the motion boundary wander amplitude, the pressure sub-intervals are divided into adjacent pressure sub-intervals along the pressure axis, and the pressure position of the motion judgment boundary is mapped to the corresponding pressure sub-intervals to form a distribution relationship; After establishing a correspondence between the pressure sub-interval and the action judgment boundary pressure position, the action judgment boundary pressure positions from the time window are collected and a set of occurrence records is formed, so that the number of occurrence records corresponds to the number of time windows. The occurrence count within the pressure sub-interval is counted using the occurrence record set to obtain the action boundary dwell density, and a dwell density distribution state is formed along the pressure axis. The statistical results of adjacent pressure sub-intervals are continuously connected and uniformly adjusted in accordance with the residence density distribution, so that the residence density forms a continuous change process on the pressure axis. Multiple adjacent pressure sub-intervals are extracted from the continuous change process to form a continuous pressure range, and this continuous pressure range is defined as the stable action boundary interval.

9. The SF6 density controller bimetallic strip adaptive matching method based on control strategy according to claim 8, characterized in that, Within adjacent pressure sub-intervals, the frequency of occurrence is continuously connected according to the pressure sequence and uniformly adjusted to make the residence density form a continuous change process on the pressure axis. Multiple adjacent pressure sub-intervals in the continuous change process are merged to form a continuous pressure range, which is defined as the stable action boundary interval.

10. The SF6 density controller bimetallic strip adaptive matching method based on control strategy according to claim 8, characterized in that, The steps for implementing adaptive matching of bimetallic strips are as follows: Based on the correspondence between the pressure position and the dwell density of the action boundary within the stable action boundary range, a preset bimetallic strip parameter library is introduced and the pressure position is mapped to each group of displacement response records to establish the correspondence. After establishing the correspondence, the bimetallic strip combinations are screened based on the residence density distribution of the action boundary, and the temperature compensation displacement and the Bourdon tube end displacement are arranged in a corresponding arrangement at the same pressure position to obtain a set of candidate combinations. The displacement difference distribution is expanded point by point through the candidate combination set, and the thickness parameter, material combination parameter and initial curvature parameter are adjusted so that the displacement difference forms a continuous change state along the pressure axis. The adjusted bimetallic strip combination is mapped to the pressure range corresponding to the motion boundary wander amplitude, and the motion pressure distribution is continuously corrected to form a new pressure arrangement relationship. Based on the corrected pressure arrangement relationship, a combination of bimetallic strips is selected that satisfies the continuous change of displacement difference and covers the pressure range of the wandering amplitude at the action boundary.

Images