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CN-121477751-B - Valve detection control method based on front end and rear end

CN121477751BCN 121477751 BCN121477751 BCN 121477751BCN-121477751-B

Abstract

The invention discloses a valve detection control method based on front and rear ends, in particular to the field of online detection of control valves, which is used for solving the problems that state degradation of a stock valve is difficult to quantify in time and acts on real-time control in long-term operation; the method comprises the steps that small stroke heuristics are executed at a front-end terminal, valve rod angular displacement and actuating mechanism driving quantity are synchronously collected under a unified time reference, a stroke subsection and a subsection-level characteristic parameter set are obtained through increment subsection fitting, a rear-end platform models the subsection-level characteristic parameter set and process constraint data on stroke subsection dimensions to generate a health constraint parameter set, the health constraint parameter set is issued to the front-end terminal, the front-end terminal carries out angle projection and action speed limitation on a target opening instruction according to the health constraint parameter set, and the integrated management of an on-line diagnosis result and control behavior of a stock valve is realized by combining angle deviation continuous monitoring, rollback control based on a historical safety position and abnormal event reporting.

Inventors

  • DENG ANYI
  • ZENG LICAI

Assignees

  • 方正阀门集团股份有限公司

Dates

Publication Date
20260512
Application Date
20260112

Claims (10)

  1. 1. The front-end and rear-end-based valve detection control method is characterized by comprising the following steps of: The method comprises the following steps of S1, self-checking and zero calibration are carried out after a front end terminal is electrified, a valve rod is driven to reciprocate and jog according to a preset probing sequence in a local small stroke of a valve, and angular displacement of the valve rod and driving quantity of an actuating mechanism are synchronously collected and stored in time sequence under a unified time reference to form small stroke probing data; s2, preprocessing small-stroke heuristic data by the front-end terminal according to a uniform time step, calculating driving quantity and displacement increment of adjacent sampling points, detecting change points and performing piecewise fitting to obtain a plurality of stroke segments on the valve rod stroke, calculating segment-level characteristic parameters reflecting friction and hysteresis for each stroke segment, generating segment-level characteristic parameter sets, and uploading the segment-level characteristic parameter sets to the rear-end platform; S3, the back-end platform receives the segment-level characteristic parameter set, and correspondingly sorts the segment-level characteristic parameter set and process constraint data of a loop to which the valve belongs in the segment dimension of the stroke, calculates friction characteristics and flow capacity of each stroke segment based on a simplified working condition model, obtains the safe opening upper limit and the maximum allowable action speed of each stroke segment, forms a health constraint parameter set and issues a front-end terminal; and S4, when receiving a target opening instruction, the front-end terminal converts the target opening into a target angle, positions the target angle on a stroke section, corrects the target angle and the action speed according to a health constraint parameter set to generate an angle track, monitors angle deviation according to sampling in the execution process, and carries out rollback control according to the last safety position and reports an abnormal event to the back-end platform when the angle deviation continuously exceeds a set standard.
  2. 2. The front-end and back-end based valve detection control method according to claim 1, wherein: when a preset heuristic sequence is generated, the front end terminal drives the valve rod to reciprocate and jog in a mode of gradually increasing the stroke amplitude in a local range of the full stroke of the valve by taking the current working condition position as the center, eliminates small-stroke heuristic data with the driving quantity and the displacement change lower than a threshold value after the angular displacement of the valve rod and the driving quantity of the actuating mechanism are acquired, and reserves the small-stroke heuristic data for stroke segmentation processing.
  3. 3. The front-end and back-end based valve detection control method according to claim 2, wherein: The step S1 further comprises that the front end terminal utilizes mechanical limit or small-amplitude reciprocating rotation of the clamping mechanism to determine the datum point of the angle sensor after zero calibration is completed, and distributes a unique probing number for each probing action under a unified time reference, simultaneously records the probing action direction, probing starting time and probing ending time, and stores the probing action direction, probing starting time and probing ending time and small-stroke probing data in a front end local buffer area.
  4. 4. The front-end and back-end based valve detection control method according to claim 3, wherein: the step S2 comprises the steps that when the front end terminal preprocesses small-stroke heuristic data, resampling is carried out on valve rod angular displacement and actuating mechanism driving quantity according to a unified time step, high-frequency noise is weakened through digital filtering, amplitude normalization processing is carried out on resampling results, and then driving quantity increment and displacement increment of adjacent sampling points are calculated to construct an increment sequence for detecting change points.
  5. 5. The front-end and back-end based valve detection control method according to claim 4, wherein: The step S2 further comprises the steps that after the front end terminal completes detection of the change points and segment fitting, a plurality of stroke segments obtained by dividing the valve rod stroke are recorded in a stroke segment dividing table according to stroke segment numbers, average slope, static friction peak value, hysteresis width and stroke segment type labels corresponding to each stroke segment are written into a segment level characteristic parameter set, and the stroke segment numbers are stored as indexes and uploaded to the rear end platform.
  6. 6. The front-end and back-end based valve detection control method according to claim 5, wherein: Step S3 comprises the step that the process constraint data at least comprise an upstream pressure allowed range, a downstream pressure allowed range, an allowed pressure difference upper limit, a target flow allowed range and medium density of a loop to which the valve belongs, and the back-end platform writes the segment-level characteristic parameter set and the process constraint data into the same joint data structure in a stroke segment dimension for constructing a simplified working condition model.
  7. 7. The front-end and back-end based valve detection control method according to claim 6, wherein: The step S3 further comprises the step that the back-end platform calculates health indexes representing friction states and driving force demands for each stroke segment on the basis of the combined data structure, classifies risk levels for the stroke segments according to a pre-established threshold interval, and forms a stroke segment record in a health constraint parameter set together with the upper limit of the safety opening of the stroke segment and the maximum allowable action speed of the stroke segment.
  8. 8. The front-end and back-end based valve detection control method according to claim 7, wherein: When the front end terminal corrects the target angle and the action speed according to the health constraint parameter set to generate an angle track, firstly, carrying out safe projection on the target angle on all travel sections related to the action path to obtain a safe target angle, then selecting the maximum action speed of the path from the maximum allowable action speeds of all travel sections, and constructing a planning angle track consisting of an acceleration section, a constant speed section and a deceleration section according to the safe target angle, the maximum action speed of the path and a sampling period.
  9. 9. The front-end and back-end based valve detection control method according to claim 8, wherein: and step S4, when the front-end terminal monitors the angle deviation according to sampling, performing multiple reference action tests on the health valve in advance, counting the distribution condition of the absolute value of the angle deviation at each sampling time, determining an angle deviation threshold according to the distribution, counting the distribution condition of continuous out-of-tolerance times in the health action, determining a continuous out-of-tolerance times standard according to the distribution, and taking the angle deviation threshold and the continuous out-of-tolerance times standard as abnormal triggering conditions during online operation.
  10. 10. The front-end and back-end based valve detection control method according to claim 9, wherein: the step S4 further comprises the steps that when the angle deviation continuously exceeds a threshold value and the back-off control is triggered, the front end terminal records the actual angle position at which the last action is finished and the angle deviation does not exceed the angle deviation threshold value as the last safe position, the last safe position is used as the back-off end point in the back-off control process, and an abnormal event record is generated after the back-off is finished, wherein the abnormal event record at least comprises an original target opening instruction, a safe target angle, an action path stroke subsection set, the maximum angle deviation, a back-off initial angle position and a back-off end angle position and is uploaded to the rear end platform.

Description

Valve detection control method based on front end and rear end Technical Field The invention relates to the field of online detection of control valves, in particular to a valve detection control method based on front and rear ends. Background In a pipe network system for long-term operation of water, gas, oil product transmission and distribution, industrial devices and the like, a large number of in-service valves are gate valves, ball valves, butterfly valves or stop valves which are configured in situ according to working conditions before many years, nameplate information, structural parameters and factory characteristic data of the in-service valves are often incomplete, and original settings of part of equipment are difficult to verify after the equipment is subjected to multiple overhauling and transformation. These stock valves are often in a high pressure or corrosive medium environment, and once slow, seizing, improper closing or malfunction occurs, they can cause pressure imbalance, critical unit shut down, leakage expansion and energy consumption increase, which causes hidden trouble to production safety and public service stability. Under the background of rising labor cost and strict supervision, an operation and maintenance unit hopes to configure on-line detection and remote control functions for the stock valve on the premise of not stopping production or stopping production as little as possible, so as to realize visualization of the running state and forward movement management and control of risks. In the prior art, aiming at a newly built or parameter-clear control valve, a digital valve positioner, an intelligent actuating mechanism and a part of stroke testing device facing a safety shut-off valve are widely adopted, under the premise of knowing valve type and nominal stroke, stroke end points, friction states and execution capacity are obtained through full-stroke self-calibration or preset stroke tests, and diagnosis results are uploaded to an upper computer or an asset management system for analysis, and meanwhile, a non-invasive monitoring device which is installed on the outer wall of a valve hand wheel, a valve rod or a pipeline in a clamping or externally attaching mode is also arranged and used for collecting a switching state or a vibration signal so as to realize remote state monitoring. The scheme has good effect on newly built or clear-parameter equipment, but in the on-line upgrading scene of the stock valve with large scale, various models and missing design data, if the full-stroke self-calibration or large-stroke test is directly adopted, the pressure fluctuation and the flow mutation are easily caused in a pipe network of pressure-bearing operation, the on-site frequent execution is difficult, if the non-invasive monitoring device is only relied on, the relation between the driving quantity of the valve in different opening ranges and the displacement of the valve rod is not detailed enough, the dead zone range, the high friction range and the stroke boundary thereof are difficult to identify in time, the diagnosis result exists in the form of warning or maintenance suggestion in many cases, the full-stroke self-calibration or the large-stroke test is not tightly coupled with a process control system, and the control instruction is difficult to avoid the known high-risk stroke range in time when being executed. Under the above engineering conditions and application constraints, how to obtain the sectional parameter information which is enough to reflect the mechanics and response characteristics of different travel ranges by using only a small amount of external measurable signals such as driving quantity and valve rod displacement on the premise of not stopping or less stopping and keeping the valve body structure unchanged, and construct safe operation constraints which can be directly adopted by a process control system on a stock valve which lacks original design data, thus becoming a core technical problem to be solved. In order to solve the above problems, a technical solution is now provided. Disclosure of Invention In order to overcome the defects in the prior art, the embodiment of the invention provides a front-end and back-end-based valve detection control method, which is characterized in that a small stroke heuristic is executed at a front end terminal, the angular displacement of a valve rod and the driving quantity of an actuating mechanism are synchronously acquired under a unified time reference, a stroke subsection and a subsection characteristic parameter set are obtained through increment subsection fitting, a back-end platform models the subsection characteristic parameter set and process constraint data in the subsection dimension of the stroke to generate a health constraint parameter set and issues the front end terminal, the front end terminal carries out angle projection and action speed limitation on a target opening instruction according t