Fault diagnosis system and method for regulating valve

Abstract

The invention discloses a fault diagnosis system and method for a regulating valve, and the system comprises a power detection module which is used for obtaining a power parameter of a driving execution mechanism; the valve position feedback module is used for acquiring execution parameters of the execution structure for driving the regulating valve; the instruction acquisition module is used for acquiring a control instruction of a control end and diagnosing a test instruction; the diagnosis test instruction is used for the valve positioner to execute setting operation; the setting module is used for acquiring a diagnosis test instruction and executing setting operation, and acquiring behavior parameters in the setting operation process to generate fault mapping for diagnosis; and the analysis module is used for acquiring response parameters generated by responding to the control instruction during actual operation, and obtaining fault information based on fault mapping comparative analysis.

Description

Technical Field

[0001] The present invention belongs to the technical field of regulating valves, and in particular relates to a fault diagnosis system and method for regulating valves. Background Art

[0002] In process industries such as oil refining, petrochemicals, chemicals, electric power, metallurgy, papermaking, pharmaceuticals, and light industry, control valves are used to control the flow of process media (liquids, gases, or mixtures), automatically adjusting process parameters such as temperature, pressure, flow, level, composition, and concentration. Their main components and control systems primarily consist of the following: valves (control valves, regulating ball valves, regulating butterfly valves, etc.), actuators (cylinders, pistons, diaphragms, and shift forks) that drive the valve opening, valve positioners that control the actuators, and electrical accessories that implement other functions. The reliability and precise control performance of control valves are crucial to process safety and production efficiency.

[0003] Frequent operation of control valves over long periods of time can be affected by mechanical wear, media corrosion, and aging in the temperature and pressure environment. This can lead to component failures, particularly failure or performance degradation of core components such as the valve positioner, actuator, control air circuit, valve throttling element, and seals. These failures can cause the valve to fail to respond correctly to commands from the DCS / PLC master controller or result in delayed responses. This can cause operating parameter deviations or oscillations at best, or even equipment downtime or even production accidents at worst.

[0004] Therefore, real-time monitoring and timely diagnosis of the health status of each component of the control valve, timely detection of potential faults and early warning are crucial to ensure the safe operation of the system and normal process production.

[0005] At present, the engineering practice of fault diagnosis of control valves, on the one hand, adds some simple fault judgments such as stuck action to the intelligent valve positioner, but this is only a small part of the entire control valve fault; on the other hand, it relies more on manual inspections to make judgments; the former cannot determine which specific component has performance degradation and more faults cannot be judged; and the latter manual inspection method is limited by technical experience and on-site observation conditions, and it is difficult to find faults, which are easy to miss and not timely. Summary of the Invention

[0006] The purpose of the present invention is to provide a fault diagnosis system for a regulating valve, which performs overall fault diagnosis on the regulating valve according to multi-faceted parameters, gives a clear conclusion on the fault location, and discovers the fault in time.

[0007] The present invention solves the technical problem by adopting a technical solution of providing a fault diagnosis system for a regulating valve, the system comprising: A power detection module is used to obtain the power parameters of the driving actuator; A valve position feedback module, used to obtain execution parameters of the actuator driving the regulating valve; An instruction acquisition module is used to obtain control instructions and diagnostic test instructions from the control end; the diagnostic test instructions are used by the valve positioner to perform setting operations; A tuning module, which acquires behavioral parameters during the tuning operation to generate a fault map for diagnosis; the behavioral parameters include at least the power parameters and the execution parameters; The analysis module is used to obtain response parameters generated in response to the control instruction during actual operation, and obtain fault information based on the fault mapping comparison analysis; the response parameters at least include the power parameters and execution parameters.

[0008] Furthermore, the diagnostic test instruction includes a random signal and a step signal; and the setting operation includes: driving the actuator based on the random signal to change the opening of the regulating valve, and obtaining a dynamically changing behavior parameter, which is recorded as a dynamic parameter; Calculating a first parameter characteristic of the dynamic parameter to generate a first mapping relationship for diagnosis; driving the actuator based on the step signal to change the state of the regulating valve, and obtaining a steady-state behavior parameter, which is recorded as a steady-state parameter; calculating a second parameter characteristic and a third parameter characteristic of the steady-state parameter, and generating a second mapping relationship and a third mapping relationship for diagnosis; The fault mapping includes a first mapping relationship, a second mapping relationship, and a third mapping relationship.

[0009] Furthermore, the fault mapping includes input items, comparison items and output items, the input items are the response parameters, the comparison items are the behavior parameters and parameter characteristics, the output items are the fault information, and the parameter characteristics include first parameter characteristics, second parameter characteristics, and third parameter characteristics.

[0010] Furthermore, it also includes: an acoustic wave acquisition module for acquiring ultrasonic parameters after the regulating valve; Valve flow monitoring module, used to obtain valve flow parameters; The behavior parameters also include ultrasonic parameters and flow parameters, and the response parameters also include ultrasonic parameters and flow parameters.

[0011] Furthermore, the instruction acquisition module is used to acquire control instructions from the control end during actual operation, or diagnostic test instructions output from the control end or other handheld operators to the valve positioner.

[0012] Furthermore, the valve position feedback module includes a valve position detection unit and a feedback conversion unit. The valve position detection unit is used to detect the driving stroke of the actuator, and the feedback conversion unit is used to convert the driving stroke into a feedback signal. The execution parameter includes the feedback signal.

[0013] The present invention also provides a method for diagnosing a fault of a regulating valve, which is applicable to the above-mentioned fault diagnosis system of a regulating valve, and the method comprises: Obtaining a diagnostic test instruction, performing a setting operation based on the diagnostic test instruction and obtaining a behavior parameter, calculating a parameter characteristic of the behavior parameter and generating a fault map; Obtain the response parameters generated by the actual runtime response to the control instruction, import the response parameters into the fault map and output the fault information Further, the diagnostic test instruction includes a random signal and a step signal; Get diagnostic test instructions, including: Determine the type of the test instruction: When it is a random signal, the behavioral parameters collected during the tuning operation are recorded as dynamic parameters; When it is a step signal, the behavioral parameters collected during the tuning operation are recorded as steady-state parameters.

[0014] Furthermore, calculating parameter characteristics of the behavior parameters and generating a fault map specifically includes: Acquiring the dynamic parameter, calculating a first parameter characteristic of the dynamic parameter, and generating a first mapping relationship for diagnosis; Acquiring the steady-state parameter, calculating a second parameter characteristic and a third parameter characteristic of the steady-state parameter, and generating a second mapping relationship and a third mapping relationship for diagnosis; Identifying a first calling condition of the first mapping relationship according to the first parameter feature, identifying a second calling condition of the second mapping relationship according to the second parameter feature, and identifying a third calling condition of the third mapping relationship according to the third parameter feature; The first calling condition, the second calling condition, and the third calling condition are associated with the first mapping relationship, the second mapping relationship, and the third mapping relationship respectively, and integrated into the fault mapping; the fault mapping includes the first mapping relationship, the second mapping relationship, and the third mapping relationship.

[0015] Furthermore, obtaining response parameters generated when executing the control instruction, importing the response parameters into the fault map and outputting fault information specifically includes: Obtaining control instructions and response parameters generated when executing the control instructions; Determine the applicable mapping relationship based on the control instruction: When the control instruction satisfies the first calling condition, importing the response parameter into the first mapping relationship and outputting fault information; When the control instruction satisfies the second calling condition, importing the response parameter into the second mapping relationship and outputting fault information; When the control instruction satisfies the third calling condition, the response parameter is imported into the third mapping relationship, and fault information is output.

[0016] In summary, the present invention has the following technical innovations and beneficial effects: 1. This invention is a relatively independent system that enables control valve fault diagnosis without changing conventional design specifications, such as the selection and configuration of the existing control valve and its associated electrical accessories. It is unrestricted when used independently; it does not interfere with the existing electrical control circuit (the closed-loop control of the valve positioner that controls the valve's opening), but only provides online passive monitoring and fault diagnosis. Therefore, this system's functional structure is highly reliable and widely accepted in engineering projects.

[0017] 2. The fault diagnosis system of the present invention ultimately obtains detailed fault information covering most faults of the entire valve and its components, such as serious faults such as refusal to operate / stuck / loss of air and power, as well as various performance degradation faults of components. This overcomes the deficiency of the existing fault diagnosis technology of a few intelligent valve positioners, which can only diagnose a small number of faults, and makes up for the shortcomings of the existing technology in intelligent equipment monitoring and diagnosis.

[0018] 3. The fault diagnosis system of the present invention is a relatively independent system. The control function of the valve positioner on the actuator and the detection function of the fault diagnosis device on the actuator are separated from each other. The valve positioner is responsible for the closed-loop control of the valve, while the diagnosis system performs passive detection and diagnosis. Whether there is a fault in the valve positioner will not affect the diagnostic reliability of the fault diagnosis device. Moreover, as one of the objects to be diagnosed, the valve positioner is an object that is more prone to failure during use. Relying on the stability of the valve positioner for fault diagnosis is a common principle defect in the existing technology, resulting in imperfect applicable objects of fault diagnosis and low reliability. The fault diagnosis system of the present invention overcomes the defect that the fault diagnosis of the existing intelligent valve positioner is heavily dependent on the reliability of the valve positioner. It not only improves the applicable objects of fault diagnosis, but also has higher reliability.

[0019] 4. The fault diagnosis system of the present invention ultimately provides clear fault information, such as component failure or performance degradation, etc., overcoming the existing fault diagnosis technology of a few intelligent valve positioners, which only provides some performance indicator data, and the relationship between the fault and the performance indicator requires manual judgment by experienced engineers.

[0020] 5. The fault diagnosis system of the present invention innovatively adopts a specific self-tuning excitation to obtain a fault mapping relationship in terms of diagnostic method. The fault mapping includes various types of fault information of various components of the control valve, thereby realizing the diagnosis of various types of valve faults.

[0021] 6. When using the fault diagnosis instrument manufactured based on this system, the design of the original control valve (such as the selection and configuration of electrical accessories) does not need to be changed. There are no new sensors that are difficult to implement without engineering conditions. It is not only suitable for new production lines, but also particularly suitable for the intelligent operation and maintenance technology upgrade and transformation of existing industrial production lines.

[0022] 7. The online fault diagnosis instrument manufactured based on this system is a new type of valve electrical accessory that can replace the current engineering practice that mainly relies on manual inspection, reduce manpower and material resources, and bring about a revolution in traditional factory operation and maintenance, turning the original regular inspection into predictive planned maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings, which are incorporated into and constitute a part of the specification, illustrate embodiments of the present invention and, together with the description, serve to explain the principles of the present invention. In the drawings, similar reference numerals are used to represent similar elements. The drawings described below are some embodiments of the present invention, but not all. It is clear that those skilled in the art can derive other drawings from these drawings without inventive effort.

[0024] Figure 1 This is a structural diagram of a fault diagnosis system for a regulating valve according to an embodiment of the present invention; Figure 2 This is a schematic diagram of a fault diagnosis system for a regulating valve according to an embodiment of the present invention; Figure 3 A flowchart for obtaining a first mapping relationship based on a random signal; Figure 4 A flow chart for obtaining the second and third mapping relationships based on the step signal; Figure 5 A flowchart for fault diagnosis based on control instructions; Figure 6 The present invention is a flowchart of a method for diagnosing a fault of a regulating valve according to an embodiment of the present invention. DETAILED DESCRIPTION

[0025] The following explains and illustrates the technical solutions of the embodiments of the present invention in conjunction with the accompanying drawings. However, the following embodiments are intended to be preferred embodiments of the present invention and are not exhaustive. Examples include various configurations of various control valves, including various types of valves, actuators, valve positioners, and various gas path designs. Other embodiments derived by those skilled in the art based on the embodiments described herein without inventive effort are also considered within the scope of protection of the present invention.

[0026] Throughout this specification, the claims, and the accompanying drawings, the terms "first," "second," and so forth are used to distinguish between different items, not to describe a particular order. Furthermore, the term "comprises" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus comprising a series of steps or modules is not limited to the listed steps or modules but may optionally include steps or modules not listed, or may include other steps or modules inherent to the process, method, product, or apparatus.

[0027] First of all, it should be clear that there are many possible faults of the control valve, such as: The compressed air is not clean and the oil and water impurities contained in it are not filtered thoroughly, which causes the internal throttle hole of the valve positioner to be blocked, resulting in the valve positioner not responding to the main controller DCS / PLC in a timely manner or failing to respond; The feedback rod of the valve positioner is frequently moved for a long time, and the feedback rod is loose, resulting in the valve positioner not responding to the main controller DCS / PLC action in a timely manner or failing; In the actuator and control air circuit, air leakage occurs due to damage to the air pipe joint, diaphragm, loose diaphragm cover bolts, etc., which causes the actuator to respond to the main controller DCS / PLC action untimely or fail to respond in time; Long-term and frequent friction of moving parts causes packing damage, increased friction between the sleeve and the valve core, valve stem misalignment, valve stem scratches, and other friction abnormalities, resulting in the valve's slow response to the main controller DCS / PLC or even failure.

[0028] Failure of valve throttling parts, such as cavitation or impurity blockage of labyrinth sleeves or small hole sleeves under the action of high temperature and high pressure media, can cause throttling failure, resulting in process parameters not meeting expectations or oscillation; Under long-term media erosion, the valve core and valve seat will cause the sealing surface or seals to be damaged, resulting in internal or external leakage, leading to media leakage.

[0029] A more serious situation is that the regulating valve cannot work when it is stuck and refuses to move, or when there is a power outage, a control signal is cut off, or the compressed air source is lost.

[0030] The control end may be a master control module, which is a digital control module used for industrial automation control, and may be implemented based on existing automation control technologies such as DCS (Distributed Control System) or PLC.

[0031] For example, during actual operation, the DCS or PLC can send a control instruction ZC to the valve positioner to control the change in valve opening to automatically adjust the medium flow in the pipeline, thereby realizing closed-loop automatic control of the valve; during actual operation, this control instruction will be collected by the instruction acquisition module of the fault diagnostic device and used to diagnose the fault of the control valve; after the fault diagnostic device is installed and before it is used, it needs to be initialized to adapt to the current control valve. At this time, specific diagnostic test instructions can be sent to the valve positioner through the control terminal such as the DCS or PLC or hand operator for adjustment operation, and the fault diagnostic device obtains the fault mapping relationship adapted to the current control valve.

[0032] In the fault diagnosis system of this application, the fault diagnostic device is initialized to obtain a mapping relationship suitable for the current control valve. However, the test signal is usually transmitted by a handheld operator, which sends a specific instruction to the valve positioner, causing the valve to actuate accordingly. The fault diagnostic device also passively obtains behavioral parameters and thus obtains the mapping relationship. In application, the DCS / PLC sends a control instruction to the valve positioner, causing the valve to actuate accordingly. The fault diagnostic device also passively obtains response parameters and diagnoses the fault. The valve's actions during diagnostic testing and actual operation are controlled by the valve positioner, and the fault diagnostic device collects data for passive detection.

[0033] See Figure 1 The regulating valve may include a power device, a valve positioner, an actuator and a valve, wherein the actuator is used to adjust the opening of the valve, the power device is used to drive the actuator, and the valve positioner adjusts the size of the driving force according to the control instruction, thereby controlling the opening of the valve.

[0034] The fault diagnosis device determines whether the regulating valve has a fault and the location of the fault by collecting parameters such as the power parameters of the power equipment and the execution parameters of the actuator, and can output clear fault information.

[0035] The main component of the fault diagnosis system of the present invention is the fault diagnostic device, which can be connected to the control terminal, power equipment, valve positioner, and actuator to obtain corresponding parameters. Multiple functional modules can be configured to implement functions such as data acquisition, comparative analysis, and fault diagnosis. The fault diagnostic device is an integrated body of these functional modules.

[0036] The power detection module is used to obtain the power parameters of the actuator. Taking the air source Ps as an example, the air pressure of the power equipment can be adjusted by the valve positioner. The air pipe between the air source and the valve positioner is the air inlet pipe, and the air pipe between the valve positioner and the actuator is the air outlet pipe. An air inlet detection unit can be installed on the air inlet pipe, and an air outlet detection unit can be installed on the air outlet pipe to obtain the air pressure parameter P, that is, the power parameter, including the air inlet parameter PA and the air outlet parameter PB. The value of these parameters can be used as the basis for subsequent fault diagnosis. The air inlet and outlet detection units can use air pressure sensors. Figure 2 The air pressure sensor A on the intake pipe is the intake detection unit, and the air pressure sensor B on the outlet pipe is the outlet detection unit.

[0037] The valve position feedback module is used to obtain the execution parameters of the actuator driving the regulating valve; since the actuator and the valve are generally mechanically driven, the ratio between the actuator's telescopic stroke and the valve opening is fixed. Therefore, after the actuator's driving stroke is detected, it can be directly converted into the valve opening.

[0038] In the present application, the valve position feedback module can be used to detect the driving stroke of the actuator and convert it into a valve opening parameter ZT, that is, an execution parameter.

[0039] Exemplarily, the valve position feedback module may include a valve position detection unit and a feedback conversion unit. The valve position detection unit is used to detect the driving stroke of the actuator. The feedback conversion unit is used to convert the driving stroke into a feedback signal. The execution parameter includes the feedback signal.

[0040] Specifically, the valve position detection unit can be a diagnostic valve position feedback rod, and the feedback conversion unit can be a sensor. The appropriate sensor can be selected based on the transmission method between the diagnostic valve position feedback rod and the actuator. For example, in a linear travel scenario, where changes in the actuator's drive stroke cause the diagnostic valve position feedback rod to synchronously move, meaning the diagnostic valve position feedback rod and the actuator extend and retract synchronously, a displacement sensor or other sensor can be used. In an angular travel scenario, where changes in the actuator's drive stroke cause the diagnostic valve position feedback rod to rotate, an angle sensor, encoder, or other sensor can be used.

[0041] It can be understood that there is a connection relationship between the valve positioner and the telescopic structure of the actuator, and the diagnostic valve position feedback rod can be designed based on this connection relationship, or designed separately; when designed separately, the diagnostic valve position feedback rod and the connection relationship do not interfere with each other and can be set on both sides of the telescopic structure, such as Figure 1 As shown in the figure, the valve positioner is located on the left side of the telescopic structure, and the diagnostic valve position feedback rod is located on the right side of the telescopic structure, and a connection relationship is established respectively.

[0042] The instruction acquisition module is used to obtain the control instructions and diagnostic test instructions of the control terminal; it can be implemented based on the circuit, see Figure 2A current sensor I can be provided to detect the magnitude of the control command ZC. Based on the magnitude of the control command ZC, the actuator's drive stroke varies, corresponding to different valve openings. For example, control command ZC values of 4mA, 8mA, 12mA, 16mA, and 20mA correspond to valve openings of 0%, 25%, 50%, 75%, and 100%. The magnitude range of the control command ZC can be adjusted based on actual needs, such as the recognition accuracy of the valve positioner and the adjustment accuracy of the valve. For example, the current sensor I can be a transformer.

[0043] Among them, the control instruction is the demand instruction generated during actual operation, which is related to the operating requirements of the control valve; the diagnostic test instruction is an artificially set operation instruction, whose purpose is to implement the setting operation, that is, to drive the valve positioner to produce corresponding actions based on the diagnostic test instruction, so that the fault diagnostic device can collect the corresponding behavioral parameters.

[0044] The fault diagnostic device can collect control instructions and diagnostic test instructions based on the same circuit; the control instructions and the diagnostic test instructions do not appear at the same time.

[0045] The valve opening parameter ZT is directly related to the control instruction ZC. After the fault diagnosis device collects the control instruction ZC and executes the control instruction ZC, the valve opening parameter ZT collected in the steady state should correspond to the executed control instruction ZC. If they do not correspond, it means that there may be a fault. Therefore, the collected control instruction ZC and valve opening parameter ZT can serve as the basis for subsequent fault judgment.

[0046] The diagnostic system of the present application also includes an acoustic wave acquisition module for obtaining ultrasonic parameters after the regulating valve; a valve flow monitoring module for obtaining the flow parameters of the valve; therefore, the behavioral parameters also include ultrasonic parameters and flow parameters, and the response parameters also include ultrasonic parameters and flow parameters.

[0047] The acoustic wave acquisition module collects ultrasonic parameters (US) at the valve. This is achieved by continuously receiving ultrasonic waves through an ultrasonic sensor. Specifically, if a leak occurs at the closed valve position, the jet of leaking media will generate turbulence. The abnormal high-frequency ultrasonic signal generated by this turbulence is received by the ultrasonic sensor and used to determine valve leakage information, which is then used for subsequent tuning operations and fault analysis.

[0048] The valve flow monitoring module is used to collect the pressure difference and medium flow before and after the valve. A pre-valve pressure detection unit can be set before the valve and a post-valve pressure detection unit can be set after the valve to obtain the pre-valve pressure parameter PT7 and the post-valve pressure parameter PT8 respectively, and the pressure difference dPT is obtained by calculation; a flow detection unit can be set after the valve to obtain the flow detection signal FT; the flow parameters may include the pressure difference dPT and the flow detection signal FT; under normal operating conditions, the pressure difference (dPT) of PT7 and PT8 should be in the expected relationship with the valve opening (ZT) and flow (FT), and therefore can be used as the basis for subsequent fault judgment.

[0049] The tuning module obtains behavioral parameters during the tuning operation to generate a fault map for diagnosis; the behavioral parameters include at least power parameters and execution parameters.

[0050] In this application, both the diagnostic test instructions and the control instructions can be controlled and triggered by the control end. The diagnostic test instructions are used to perform specific setting operations. The setting operations are used to obtain the behavioral parameters of the control valve (including power equipment, valve positioners, actuators, valves and other components) under normal conditions, and use the normal behavioral parameters to perform fault diagnosis on the response parameters generated in the subsequent actual operation of the control valve.

[0051] During the setting operation, the handheld operator or control terminal can output diagnostic test instructions. The output object is the valve positioner, which makes the valve positioner move and can synchronously drive the actuator and valve to move. During this process, the fault diagnostic device collects the corresponding behavioral parameters and the diagnostic test instructions through the instruction acquisition module.

[0052] During the use of the control valve, according to different needs, it may include the following three situations: dynamic adjustment, closing, and fixed opening. Therefore, corresponding diagnostic test instructions should be set to adapt to the three situations, so that the fault diagnosis based on behavioral parameters can be more targeted, accurate and effective.

[0053] The signal types of the diagnostic test instructions can be divided into random signals and step signals. Among them, dynamic adjustment can be tested by random signals, and steady-state adjustment (closing, fixed opening) can be tested by step signals.

[0054] It should be clear that when dynamic adjustment is performed with a random signal, the collected behavioral parameters also change dynamically. When steady-state adjustment is performed with a step signal, the collected behavioral parameters are fixed values.

[0055] Therefore, when performing fault diagnosis based on behavioral parameters, the present application distinguishes the two, performs fault analysis separately, and forms different mapping relationships with fault information.

[0056] In the embodiment of the present application, the tuning operation can be performed based on the type of the test instruction to obtain the behavior parameters of the corresponding state, specifically: Based on the random signal, the actuator is driven to change the opening of the regulating valve, and the dynamic behavior parameters are obtained, which are recorded as dynamic parameters; Calculating a first parameter feature of a dynamic parameter to generate a first mapping relationship for diagnosis; Based on the step signal, the actuator is driven to change the state of the regulating valve, and the steady-state behavior parameters are obtained, which are recorded as steady-state parameters; Calculating a second parameter characteristic and a third parameter characteristic of the steady-state parameter, and generating a second mapping relationship and a third mapping relationship for diagnosis; The fault mapping includes a first mapping relationship, a second mapping relationship, and a third mapping relationship.

[0057] In this application, behavioral parameters include dynamic parameters, execution parameters, etc. When adjusting the valve, each parameter has a correlation. Therefore, for the behavioral parameters under normal conditions, they have obvious behavioral characteristics, which are manifested in the parameters, namely parameter characteristics. Parameter characteristics can be for a single parameter or for multiple parameters. Based on these parameter characteristics, the collected response parameters are compared and analyzed to obtain corresponding fault information. Of course, fault information can also be measured through experiments.

[0058] In a possible embodiment, the fault information may include performance degradation information, refusal to operate information, malfunction information, power failure information, and gas failure information of each component.

[0059] by Figure 1 Taking the regulating valve structure in as an example, the corresponding fault information can be obtained by comparing and analyzing the collected response parameters based on the fault mapping: For example, if the control instructions ZC, PA, PB and the valve opening parameter ZT are collected and the parameter characteristics are calculated, the corresponding fault information obtained based on the comparative analysis of the parameter characteristics may include action faults, such as actuator fault information, such as refusal to move, stuck, etc.; valve positioner action faults, such as air leakage, oil and water blockage, etc.; power equipment action faults, such as air leakage, air loss, etc.

[0060] If the collected control instruction ZC is not equal to zero, the ultrasonic parameters are collected and their parameter characteristics are calculated. Based on the comparison and analysis of the parameter characteristics in the fault mapping, the corresponding fault information may include a throttling fault; the parameter characteristics may specifically be a valve flow coefficient.

[0061] If the collected control instruction ZC is equal to zero, ultrasonic parameters and flow parameters are collected, and their parameter characteristics are calculated, then the corresponding fault information obtained by comparative analysis in the fault map based on the parameter characteristics may include a leakage fault.

[0062] In one possible embodiment, detailed fault information includes valve leakage information. Valve leakage can be caused by a variety of factors, such as internal leakage from the valve seat due to wear and cavitation of the valve core and valve seat, and external leakage due to aging and deformation of the valve cover packing or flange seal. When gas or liquid leaks, gas turbulence occurs at the leak site, generating high-frequency ultrasonic signals (typically >20 kHz, which is beyond the range of human hearing).

[0063] If a leak occurs when the valve is in the fully closed state, the ultrasonic sensor captures these signals and converts them into digital signals that can be processed by the analysis module. The analysis module calculates them (which can be done through noise reduction preprocessing and feature signal extraction in existing technologies) and then compares and analyzes them with the basic background acoustic wave parameters in the acquired fault map to determine the final leakage information.

[0064] The acoustic wave acquisition module collects two ultrasonic parameters, US, when the valve is fully open or fully closed. Under normal circumstances (i.e., when there is no leakage), these two ultrasonic parameters, US, represent the basic background noise at the valve in the fully open (or 10% open) or fully closed states. These two ultrasonic parameters, US, are used as the basis for generating parameter diagnostic information. For example, when the valve is in the fully closed position, the collected ultrasonic parameters US can be used to determine and obtain valve leakage information.

[0065] The above is an example of comparative analysis of some fault information of the control valve, which is achieved based on the comparative analysis of power parameters (such as PA, PB), execution parameters (such as ZT), flow parameters (such as PT7, PT8, dPT, FT), ultrasonic parameters (such as US), and control instructions (ZC) with behavioral parameters and their parameter characteristics.

[0066] In this application, a mapping relationship is established based on the behavior parameters and their parameter characteristics and fault information. When the response parameters are collected, they are used as input items and compared with the behavior parameters and parameter characteristics, and the fault information is output according to the mapped results of the comparison results.

[0067] Taking the three parameters PA, PB, and ZT as an example, a mapping relationship with fault information can be established, where PA is the first parameter, PB is the second parameter, and ZT is the third parameter. The mapping result can be obtained by importing the collected response parameters: The above three exemplary parameters are imported to calculate the parameter features. The parameter features include multiple feature quantities. For example, the specific forms of the feature quantities may include the changing rate of the first parameter, the changing rate of the second parameter, the covariance of the first parameter, the second parameter and the third parameter, the mode of the third parameter, the power spectrum, the variance of the first parameter, the second parameter and the third parameter, etc.; the number, nature, type and correlation of the feature quantities can be adjusted and selected at will.

[0068] Based on the change of the characteristic quantity within the parameter feature, multiple mapping structures can be obtained, each or multiple mapping structures corresponds to a mapping result, and each mapping result corresponds to a clear fault information; it can be understood that the change of the characteristic quantity can be single or multiple linked.

[0069] It should be clear that based on the changes in characteristic quantities, accurate and refined fault analysis results can be obtained. Parameter characteristics can include two types. The first type is the property characteristics of a single parameter, and the second type is the association characteristics of multiple parameters. Multiple parameters can be any two or three or more parameters with correlation. The correlation between parameters and the correlation between characteristic quantities can be consistent or related, that is, the correlation between parameters can affect the selection and calculation methods of parameters in the characteristic quantities.

[0070] In one feasible embodiment, the random signal may cover all values of valve opening from 0% to 100%, thereby obtaining a first mapping relationship for adjustment under any valve opening background. It should be noted that the random signal may include an initial value and a target value, where the initial value is the current valve opening and the target value is the desired valve opening.

[0071] In one feasible embodiment, the amplitude of the step signal can be 10%, thereby obtaining the third mapping relationship under the background of 10% valve opening. At the same time, the initial amplitude of the step signal can be set to 0%, that is, the valve is fully closed, thereby obtaining the second mapping relationship under the background of the valve being fully closed.

[0072] For example, see Figure 3 When the diagnostic test instruction is a random signal, the regulating valve is driven to perform a corresponding controlled action based on the random signal, and the fault diagnosis device obtains a first mapping relationship based on the collected behavioral data and the first parameter characteristics; specifically, the content of the first parameter characteristics may include: mode, power spectrum, variance, covariance, change speed, acceleration, etc., and can be calculated based on one parameter or multiple parameters.

[0073] For example, see Figure 4 When the diagnostic test instruction is a step signal, the regulating valve is driven to perform a corresponding controlled action based on the step signal, and the fault diagnostic device obtains a second mapping relationship based on the collected behavioral data and the second parameter characteristics; specifically, the second parameter characteristics can be the valve flow coefficient Kv (ZT), Figure 4 The calculation method of valve flow coefficient is shown in FIG.

[0074] The fault diagnostic device then obtains a third mapping relationship based on the collected behavioral data and the third parameter characteristics. Specifically, the third parameter characteristics may include the background noise US0 when the valve is fully closed and at 10% opening, namely, the ultrasonic parameters when the valve is fully closed and at 10% opening. Based on the ultrasonic parameter US0 when the valve is at 10% opening, when the ultrasonic parameter US1 when the valve is fully closed is collected, the device can determine whether the valve is fully closed and whether there is a leak by comparing US1 with US0.

[0075] The analysis module is used to obtain the response parameters generated by the actual operation response control instructions, and obtain fault information based on the fault mapping comparison analysis; the response parameters include at least power parameters and execution parameters.

[0076] The analysis module can be used in the normal working state of the control valve. Under the normal working state (actual operation), it collects response parameters for fault diagnosis, monitors the status of the control valve, ensures the stable function of the control valve, and promptly feedbacks fault information.

[0077] Specifically, the analysis module can compare and analyze the collected response parameters based on the fault mapping and output fault information.

[0078] In a feasible embodiment, a communication unit may be provided between the analysis module and the control end (specifically, such as a DCS, PLC, or SCADA). The communication unit may transmit feedback information (fault information) from the analysis module via an analog current signal or a digital signal; it may also be implemented via wireless communication.

[0079] Taking the parallel transmission of analog current and digital signals as an example, the communication unit is used to achieve parallel transmission of analog current signals and HART digital signals. The 4-20mA analog current signal can transmit valve position (valve opening) and fault indication information, while the HART digital signal can transmit digital fault codes representing detailed fault information (each fault type corresponds to a digital fault code) and commands from the main control module (control instructions, diagnostic test instructions, etc.).

[0080] It should be clear that the control instruction is the actual requirement of the regulating valve during operation, and the diagnostic test instruction is the test requirement. The content and form of the two can be the same, such as both are current signals.

[0081] See Figure 5 ,After the fault mapping is obtained, during the use of the control valve, various ,parameters can be collected through the fault diagnostic device, the ,status of the control valve can be monitored, and the corresponding fault ,information can be output.

[0082] Applicable states may include dynamic regulation and steady-state regulation, wherein dynamic regulation applies the first mapping relationship, and steady-state regulation is divided into two states: steady-state throttling and valve fully closed, which apply the second mapping relationship and the third mapping relationship respectively.

[0083] The type of the control instruction ZC can be judged to determine the applicable mapping relationship. For example, the dynamically adjusted current range is defined as a dynamic electrical signal of 4~24mA, and the steady-state adjusted current is defined as an electrical signal with a fixed value. When the control instruction ZC is collected, its type can be directly judged, and then the corresponding mapping relationship can be called.

[0084] Of course, the data structure of the control instruction ZC may also be designed, and an identification code may be embedded in the data structure. The type of the control instruction ZC may be determined by the identification code, thereby calling a corresponding mapping relationship.

[0085] See also Figure 6 The present invention also provides a control valve fault diagnosis method, which is applicable to the above-mentioned control valve fault diagnosis system. Its execution body is a fault diagnosis device, which obtains various parameters of the control valve, thereby realizing the fault diagnosis of the control valve and outputting fault information.

[0086] S101, obtaining a diagnostic test instruction, performing a setting operation based on the diagnostic test instruction and obtaining behavior parameters, calculating parameter characteristics of the behavior parameters and generating a fault map; The diagnostic test instruction includes a random signal and a step signal. A first mapping relationship is obtained based on the random signal. A second and a third mapping relationship are obtained based on the step signal. The fault mapping includes the first mapping relationship, the second mapping relationship, and the third mapping relationship.

[0087] In the embodiment of the present application, when obtaining a diagnostic test instruction, its type is detected, and the parameters collected after execution are distinguished to obtain dynamic parameters and steady-state parameters, specifically including: Determine the type of the test instruction: When it is a random signal, the behavioral parameters collected during the tuning operation are recorded as dynamic parameters; When it is a step signal, the behavioral parameters collected during the tuning operation are recorded as steady-state parameters.

[0088] In an embodiment of the present application, based on the acquired dynamic parameters, a first parameter feature of the dynamic parameters is calculated to generate a first mapping relationship for diagnosis; Based on the acquired steady-state parameters, second parameter characteristics and third parameter characteristics of the steady-state parameters are calculated, and second mapping relationships and third mapping relationships for diagnosis are generated.

[0089] When performing diagnosis, the corresponding mapping relationship should be called according to the type of control instruction. For example, when the control instruction is dynamic adjustment, the first mapping relationship should be called for diagnosis; when the control instruction is throttling adjustment, the second mapping relationship should be called for diagnosis; when the control instruction is closing adjustment, the third mapping relationship should be called for diagnosis.

[0090] In the embodiment of the present application, conditions can be added to each mapping relationship. When diagnosing based on fault mapping, the collected control instructions are first judged, and the mapping relationship that meets the conditions is called for diagnosis, specifically including: Identifying a first calling condition of the first mapping relationship according to the first parameter feature, identifying a second calling condition of the second mapping relationship according to the second parameter feature, and identifying a third calling condition of the third mapping relationship according to the third parameter feature; The first calling condition, the second calling condition, and the third calling condition are associated with the first mapping relationship, the second mapping relationship, and the third mapping relationship respectively, and integrated into a fault mapping.

[0091] Fault mapping includes the first mapping relationship, the second mapping relationship, and the third mapping relationship, corresponding to Figure 5 Among them, the fault type output by the first mapping relationship is action fault, and the action fault information can be divided into air leakage or blockage, oil and water blockage in the valve positioner, loose feedback rod, abnormal friction, etc.; power failure, signal failure, air loss, etc.; stuck or refusal to move, malfunction, etc.; the fault type output by the second mapping relationship is throttling fault, and throttling fault information may include sleeve cavitation, sleeve blockage, etc.; the fault type output by the third mapping relationship is leakage fault, and leakage fault information may include valve seat internal leakage, etc.

[0092] See Figure 5 The first calling condition is that the control instruction ZC is dynamically changing, such as a dynamic electrical signal; the second calling condition is that the control instruction ZC is steady-state, ZC≠0 and the valve is not closed, such as an electrical signal with a fixed value representing a valve opening of 20%; the third calling condition is that the control instruction ZC is steady-state, the valve is closed, ZC=0, such as an electrical signal with a fixed value representing a valve opening of 0%.

[0093] S102 , obtaining response parameters generated when executing the control instruction, importing the response parameters into the fault map and outputting fault information.

[0094] In the embodiments of the present application, the regulating valve may include any state requirements when in use, such as dynamic regulation, throttling regulation, closing regulation, etc. Therefore, when performing fault diagnosis based on mapping faults, the control instructions should be collected first, and the corresponding mapping relationship should be called based on the control instructions, and then the response parameters should be analyzed and compared, so as to output the corresponding fault information.

[0095] The fault mapping of this application includes multiple mapping relationships, each of which has an independent applicable state. When performing fault diagnosis based on the mapping fault, it specifically includes: Obtain control instructions and response parameters generated when executing control instructions; Determine the applicable mapping relationship based on the control instructions: When the control instruction satisfies the first calling condition, the response parameter is imported into the first mapping relationship, and the fault information is output; When the control instruction satisfies the second calling condition, the response parameter is imported into the second mapping relationship, and the fault information is output; When the control instruction satisfies the third calling condition, the response parameter is imported into the third mapping relationship, and the fault information is output.

[0096] In this application, the fault diagnostic device collects the control instruction ZC and the response parameters (ZT, PA, PB, dPT, FT, US) generated by executing the control instruction ZC, obtains the corresponding fault information through comparative analysis of the mapping relationship, and timely feedback is given on the status of the control valve.

[0097] After receiving a fault indication, (fault) alarms, (performance degradation) warnings, etc. can be issued based on the specific fault details. At the same time, each fault information can be numbered. After receiving a fault indication, the number can be used as the fault content for alarm and data upload for easy recording.

[0098] It should be emphasized that the integration of the fault diagnosis system proposed in this invention with the actual hardware components, such as valves, valve positioners, and actuators, is not limited to the aforementioned embodiments. Any hardware implementation variations resulting from differences in the configuration of the control valve's air circuits and electrical accessories, any technical solutions for integrating the fault diagnosis system with other control valve components, and any solutions for integrating the functions of the tuning module and / or analysis module into a host computer or platform, fall within the scope of protection of this disclosure.

[0099] In the several embodiments provided in this application, it should be understood that the disclosed devices can be implemented in other ways. For example, the module embodiments described above are merely illustrative. For example, the division of the modules is merely a logical function division. In actual implementation, there may be other division methods, such as multiple modules, modules or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some service interface, and the indirect coupling or communication connection of the device or module can be electrical or other forms.

[0100] The modules described as separate components may or may not be physically separate, and the components shown as modules may or may not be physical modules, that is, they may be located in one place or distributed across multiple network modules. Some or all of the modules may be selected to achieve the purpose of the present embodiment according to actual needs.

[0101] In addition, the functional modules in the various embodiments of the present application may be integrated into a processing module, or each module may exist physically separately, or two or more modules may be integrated into a single module. The above-mentioned integrated modules may be implemented in the form of hardware or software functional modules.

[0102] The above description is merely a description of the preferred embodiments disclosed in this application and the technical principles employed. Those skilled in the art should understand that the scope of protection provided by this disclosure is not limited to technical solutions formed by a specific combination of the aforementioned technical features, but also encompasses other technical solutions formed by any combination of the aforementioned technical features or their equivalents without departing from the scope of the disclosure. For example, a technical solution formed by replacing the aforementioned features with (but not limited to) technical features with similar functions disclosed in this disclosure.

Claims

1. A fault diagnosis system for a regulating valve, characterized in that the system include: A power detection module is used to obtain the power parameters of the driving actuator; A valve position feedback module, used to obtain execution parameters of the actuator driving the regulating valve; An instruction acquisition module is used to obtain control instructions and diagnostic test instructions from the control end; the diagnostic test instructions are used by the valve positioner to perform setting operations; A tuning module, which acquires behavioral parameters during the tuning operation to generate a fault map for diagnosis; the behavioral parameters include at least the power parameters and the execution parameters; The analysis module is used to obtain response parameters generated in response to the control instruction during actual operation, and obtain fault information based on the fault mapping comparison analysis; the response parameters at least include the power parameters and execution parameters.

2. A fault diagnosis system for a regulating valve according to claim 1, characterized in that: The diagnostic test instructions include random signals and step signals; the setting operations include: driving the actuator based on the random signal to change the opening of the regulating valve, and obtaining a dynamically changing behavior parameter, which is recorded as a dynamic parameter; Calculating a first parameter characteristic of the dynamic parameter to generate a first mapping relationship for diagnosis; driving the actuator based on the step signal to change the state of the regulating valve, and obtaining a steady-state behavior parameter, which is recorded as a steady-state parameter; calculating a second parameter characteristic and a third parameter characteristic of the steady-state parameter, and generating a second mapping relationship and a third mapping relationship for diagnosis; The fault mapping includes a first mapping relationship, a second mapping relationship, and a third mapping relationship.

3. A fault diagnosis system for a regulating valve according to claim 2, characterized in that: The fault mapping includes input items, comparison items and output items, the input items are the response parameters, the comparison items are the behavior parameters and parameter characteristics, the output items are the fault information, and the parameter characteristics include first parameter characteristics, second parameter characteristics, and third parameter characteristics.

4. A fault diagnosis system for a regulating valve according to claim 1, characterized in that: It also includes: an acoustic wave acquisition module for acquiring ultrasonic parameters after the regulating valve; Valve flow monitoring module, used to obtain valve flow parameters; The behavior parameters also include ultrasonic parameters and flow parameters, and the response parameters also include ultrasonic parameters and flow parameters.

5. The fault diagnosis system for a regulating valve according to claim 1, characterized in that: The valve position feedback module includes a valve position detection unit and a feedback conversion unit. The valve position detection unit is used to detect the driving stroke of the actuator. The feedback conversion unit is used to convert the driving stroke into a feedback signal. The execution parameter includes the feedback signal.

6. A method for diagnosing a fault of a regulating valve, characterized in that: A fault diagnosis system for a regulating valve according to claim 1, wherein the method comprises: Obtaining a diagnostic test instruction, performing a setting operation based on the diagnostic test instruction and obtaining a behavior parameter, calculating a parameter characteristic of the behavior parameter and generating a fault map; Acquire response parameters generated in response to the control instruction during actual operation, import the response parameters into the fault map and output fault information.

7. A fault diagnosis method for a regulating valve according to claim 6, characterized in that: The diagnostic test instructions include random signals and step signals; Get diagnostic test instructions, including: Determining the type of the test instruction; When it is a random signal, the behavioral parameters collected during the tuning operation are recorded as dynamic parameters; When it is a step signal, the behavioral parameters collected during the tuning operation are recorded as steady-state parameters.

8. A fault diagnosis method for a regulating valve according to claim 7, characterized in that: Calculating parameter characteristics of the behavioral parameters and generating a fault map, specifically including: Acquiring the dynamic parameter, calculating a first parameter characteristic of the dynamic parameter, and generating a first mapping relationship for diagnosis; Acquiring the steady-state parameter, calculating a second parameter characteristic and a third parameter characteristic of the steady-state parameter, and generating a second mapping relationship and a third mapping relationship for diagnosis; Identifying a first calling condition of the first mapping relationship according to the first parameter feature, identifying a second calling condition of the second mapping relationship according to the second parameter feature, and identifying a third calling condition of the third mapping relationship according to the third parameter feature; The first calling condition, the second calling condition, and the third calling condition are associated with the first mapping relationship, the second mapping relationship, and the third mapping relationship respectively, and integrated into the fault mapping; the fault mapping includes the first mapping relationship, the second mapping relationship, and the third mapping relationship.

9. A fault diagnosis method for a regulating valve according to claim 8, characterized in that: Acquiring response parameters generated when executing control instructions, importing the response parameters into the fault map and outputting fault information, specifically including: Obtaining control instructions and response parameters generated when executing the control instructions; Determine the applicable mapping relationship based on the control instruction: When the control instruction satisfies the first calling condition, importing the response parameter into the first mapping relationship and outputting fault information; When the control instruction satisfies the second calling condition, importing the response parameter into the second mapping relationship and outputting fault information; When the control instruction satisfies the third calling condition, the response parameter is imported into the third mapping relationship, and fault information is output.

10. A regulating valve, characterized in that: A fault diagnosis system for a regulating valve comprising at least a valve, a valve positioner, a pressure reducing valve, an actuator, and the like; the valve, the valve positioner, and the actuator are all connected to the fault diagnosis system.

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