An electric valve fault diagnosis method and system, and a storage medium

Abstract

The embodiment of the application discloses a kind of electric valve fault diagnosis method, system and storage medium, comprising: according to the working state of electric valve, the diagnostic variable standard signal of electric valve is adaptively established;Determine whether the working state of current electric valve changes compared with the working state of previous electric valve, if yes, then according to the working state of current electric valve, the diagnostic variable standard signal of electric valve is adaptively re-established;According to diagnostic variable standard signal, diagnostic variable threshold is adaptively updated;Obtain the diagnostic variable when electric valve switch operates;Diagnostic variable and diagnostic variable threshold are compared, to determine whether electric valve fails according to the size relationship of diagnostic variable and diagnostic variable threshold;The technical problem that the accuracy degree of the present application embodiment avoids using machine learning method to carry out fault identification depends on the size of data amount and the accuracy degree of data acquisition.

Description

Technical Field

[0001] This invention relates to a method, system, and storage medium for diagnosing faults in electric valves. Background Technology

[0002] Electric valves are widely used in industrial applications, and some valves, such as nuclear-grade valves, are prone to failure due to their operation in harsh environments. Current research on valve fault diagnosis methods largely utilizes machine learning algorithms to classify valve fault data for diagnosis. The paper "A Valve Fault Diagnosis Method Based on Optimized SVM-DT" addresses the challenges of diverse and similar valve fault types in process control systems, as well as the strong nonlinearity of fault data. It proposes a valve fault classification algorithm based on Support Vector Machine Decision Tree (SVM-DT), using an improved genetic algorithm to optimize the SVM parameters, which significantly impact the recognition rate. The paper "Application of Pattern Recognition Technology in Fault Diagnosis of Safety-Grade Electric Valves" applies a fault detection system for safety-grade electric isolation valves to valve fault detection, using pattern recognition technology to identify fault types, analyze real-time faults, and provide identification results. The paper "Research on Fault Diagnosis of Solenoid Valves Based on Drive-End Current Detection" also applies a fault detection system for safety-grade electric isolation valves to valve fault detection, using pattern recognition technology to identify fault types, analyze real-time faults, and provide identification results.

[0003] The valve diagnostic methods described above all utilize machine learning for fault identification, which often depends on the amount of data and the accuracy of data acquisition. Summary of the Invention

[0004] To address the technical problem that the accuracy of fault identification using existing machine learning methods depends on the amount of data and the accuracy of data acquisition, this invention provides a method, system, and storage medium for diagnosing electric valve faults, enabling fault diagnosis of electric valves without relying on the amount of data.

[0005] The embodiments of the present invention are achieved through the following technical solutions:

[0006] In a first aspect, the present invention provides a method for diagnosing faults in an electric valve, comprising:

[0007] The standard signals for diagnostic variables of electric valves are adaptively established based on their operating status.

[0008] Determine whether the current working state of the electric valve has changed compared to the previous working state. If so, adaptively re-establish the standard signal of the diagnostic variable of the electric valve based on the current working state.

[0009] The thresholds of diagnostic variables are adaptively updated based on the standard signals of the diagnostic variables.

[0010] Obtain diagnostic variables during the operation of electric valve switching;

[0011] The diagnostic variable is compared with the diagnostic variable threshold to determine whether the electric valve has malfunctioned based on the relationship between the two values.

[0012] Furthermore, the operating states of electric valves include different operating conditions, long-term disturbances, and / or instantaneous disturbances.

[0013] Furthermore, the diagnostic variables include:

[0014] X-axis vibration signal power spectral entropy, Y-axis vibration signal power spectral entropy, Z-axis vibration signal power spectral entropy, a-phase current mean, b-phase current mean, c-phase current mean and / or average power.

[0015] Furthermore, determine whether the current operating state of the electric valve has changed compared to its previous operating state; including:

[0016] Compare the diagnostic variables of a previous action of the electric valve with the diagnostic variables generated by the current action of the electric valve. If the difference between the diagnostic variables of a previous action of the electric valve and the diagnostic variables generated by the current action of the electric valve is greater than a specified value, it is determined that the working state of the current electric valve has experienced a short-term disturbance compared to the previous working state of the electric valve.

[0017] Furthermore, determine whether the current operating state of the electric valve has changed compared to its previous operating state; including:

[0018] The diagnostic variables of the electric valve that have performed more than two actions before the current electric valve action are weighted and calculated to obtain a weighted value.

[0019] Compare the weighted value with the diagnostic variable generated by the current electric valve action. If the difference between the weighted value and the diagnostic variable generated by the current electric valve action is greater than a specified value, it is determined that the current working state of the electric valve has experienced a long-term disturbance compared to the previous working state of the electric valve.

[0020] Furthermore, the diagnostic variable is compared with its threshold value to determine whether the electric valve has malfunctioned based on the relationship between the two values; this includes:

[0021] When the diagnostic variable includes current, the current is compared with the current threshold. If the current is greater than the current threshold, it is determined that a stalled rotor, a short circuit, or a severe jamming fault has occurred.

[0022] When the diagnostic variable includes power spectral entropy, the difference in power spectral entropy signals is compared with the power spectral entropy threshold. If the difference in power spectral entropy signals is greater than the power spectral entropy threshold, the valve is determined to be faulty.

[0023] When the diagnostic variable includes average power, the difference in the average power signal is compared with the average power threshold. If the difference in the average power signal is greater than the average power threshold, the valve is determined to be faulty. At this time, it is determined whether the difference in the current signal is greater than the threshold. If the difference in the current signal is greater than the threshold, the valve motor is determined to be stalled or stuck. Otherwise, a voltage fault is determined.

[0024] Furthermore, it also includes:

[0025] The fault diagnosis results are output in the form of level signals; if the level signal is high, it indicates that a fault has occurred; if the level signal is low, it indicates that no fault has occurred; if the level signal is the first fault level signal, it indicates that the valve is stuck; if the level signal is the second fault level signal, it indicates that the valve is short-circuited; if the level signal is the third fault level signal, it indicates that the valve power supply voltage is abnormal.

[0026] Furthermore, diagnostic variable standard signals for the electric valve are adaptively established based on its operating state; including:

[0027] The diagnostic variable signals generated by the switching action of the electric valve in the working state are stored as diagnostic variable standard signals;

[0028] The diagnostic variables include: X-axis vibration signal power spectral entropy, Y-axis vibration signal power spectral entropy, Z-axis vibration signal power spectral entropy, mean a-phase current, mean b-phase current, mean c-phase current, and average power.

[0029] In a second aspect, embodiments of the present invention include an electric valve fault diagnosis system, comprising:

[0030] The diagnostic variable standard signal generation unit is used to adaptively establish the diagnostic variable standard signal of the electric valve according to the working state of the electric valve.

[0031] The judgment unit is used to determine whether the current working state of the electric valve has changed compared to the previous working state of the electric valve. If so, the diagnostic variable standard signal of the electric valve is adaptively re-established according to the current working state of the electric valve.

[0032] The update unit is used to adaptively update the threshold of the diagnostic variable based on the standard signal of the diagnostic variable;

[0033] The acquisition unit is used to acquire diagnostic variables during the operation of the electric valve switching; and

[0034] The comparison and determination unit is used to compare the diagnostic variable with the diagnostic variable threshold to determine whether the electric valve has malfunctioned based on the relationship between the size of the diagnostic variable and the diagnostic variable threshold.

[0035] Thirdly, embodiments of the present invention provide a storage medium on which instructions are stored, and when the instructions are executed on a computer, the electric valve fault diagnosis method is performed.

[0036] Compared with the prior art, the embodiments of the present invention have the following advantages and beneficial effects:

[0037] This invention discloses an electric valve fault diagnosis method, system, and storage medium. The method adaptively establishes standard diagnostic variable signals for the electric valve based on its operating state. It then determines whether the current operating state of the electric valve has changed compared to its previous state; if so, it adaptively re-establishes the standard diagnostic variable signals based on the current operating state; it adaptively updates the diagnostic variable thresholds based on the standard diagnostic variable signals; it acquires the diagnostic variables during the electric valve's on / off operation; and it compares the diagnostic variables with the diagnostic variable thresholds to determine whether the electric valve has malfunctioned based on the relationship between the two values. This avoids the technical problem of the accuracy of fault identification using machine learning methods depending on the amount of data and the accuracy of data acquisition. Attached Figure Description

[0038] To more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1 This is a flowchart illustrating the fault diagnosis method for electric valves.

[0040] Figure 2 This is a schematic diagram of an electric valve fault diagnosis system.

[0041] Figure 3 A flowchart is created for the power spectral entropy standard signal.

[0042] Figure 4 Establish a flowchart for the current standard signal.

[0043] Figure 5 Create a flowchart for the average power standard signal.

[0044] Figure 6 This is a schematic diagram of a diagnostic model based on standard values ​​and measured values.

[0045] Figure 7 This is a schematic diagram of the working process of an electric valve fault diagnosis device. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and are not intended to limit the present invention.

[0047] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that these specific details are not necessary to practice the invention. In other embodiments, well-known structures, circuits, materials, or methods have not been specifically described in order to avoid obscuring the invention.

[0048] Throughout this specification, references to "an embodiment," "an example," or "an example" mean that a particular feature, structure, or characteristic described in connection with that embodiment or example is included in at least one embodiment of the invention. Therefore, the phrases "an embodiment," "an example," "an example," or "an example" appearing in various places throughout the specification do not necessarily refer to the same embodiment or example. Furthermore, specific features, structures, or characteristics can be combined in one or more embodiments or examples in any suitable combination and / or sub-combination. Moreover, those skilled in the art will understand that the illustrations provided herein are for illustrative purposes and are not necessarily drawn to scale. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0049] In the description of this invention, the terms "front", "rear", "left", "right", "up", "down", "vertical", "horizontal", "high", "low", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this invention.

[0050] Example

[0051] To address the technical problem that the accuracy of fault identification using existing machine learning methods depends on the size of the data and the accuracy of data acquisition, this invention provides a method, system, and storage medium for diagnosing electric valve faults, enabling fault diagnosis of electric valves without relying on the amount of data. In a first aspect, this invention provides a method for diagnosing electric valve faults, referring to... Figure 1As shown, it includes:

[0052] S1. Adaptively establish standard signals for diagnostic variables of the electric valve based on its operating status;

[0053] S2. Determine whether the current working state of the electric valve has changed compared to the previous working state of the electric valve. If so, adaptively re-establish the standard signal of the diagnostic variable of the electric valve according to the current working state of the electric valve.

[0054] S3. Adaptively update the threshold of the diagnostic variable based on the standard signal of the diagnostic variable;

[0055] S4. Obtain diagnostic variables during the operation of the electric valve switch;

[0056] S5. Compare the diagnostic variable with the diagnostic variable threshold to determine whether the electric valve has malfunctioned based on the relationship between the two values.

[0057] Therefore, this embodiment of the invention adaptively establishes a standard signal for diagnostic variables of the electric valve based on its operating state; determines whether the current operating state of the electric valve has changed compared to the previous operating state; if so, adaptively re-establishes the standard signal for diagnostic variables based on the current operating state of the electric valve; adaptively updates the diagnostic variable threshold based on the standard signal for diagnostic variables; obtains the diagnostic variables during the opening and closing operation of the electric valve; and compares the diagnostic variables with the diagnostic variable threshold to determine whether the electric valve has malfunctioned based on the relationship between the size of the diagnostic variables and the diagnostic variable threshold. This avoids the technical problem that the accuracy of fault identification using machine learning methods depends on the size of the data and the accuracy of data acquisition.

[0058] Furthermore, the operating states of electric valves include different operating conditions, long-term disturbances, and / or instantaneous disturbances.

[0059] Furthermore, the diagnostic variables include:

[0060] X-axis vibration signal power spectral entropy, Y-axis vibration signal power spectral entropy, Z-axis vibration signal power spectral entropy, a-phase current mean, b-phase current mean, c-phase current mean and / or average power.

[0061] Furthermore, determine whether the current operating state of the electric valve has changed compared to its previous operating state; including:

[0062] Compare the diagnostic variables of a previous action of the electric valve with the diagnostic variables generated by the current action of the electric valve. If the difference between the diagnostic variables of a previous action of the electric valve and the diagnostic variables generated by the current action of the electric valve is greater than a specified value, it is determined that the working state of the current electric valve has experienced a short-term disturbance compared to the previous working state of the electric valve.

[0063] Furthermore, determine whether the current operating state of the electric valve has changed compared to its previous operating state; including:

[0064] The diagnostic variables of the electric valve that have performed more than two actions before the current electric valve action are weighted and calculated to obtain a weighted value.

[0065] Compare the weighted value with the diagnostic variable generated by the current electric valve action. If the difference between the weighted value and the diagnostic variable generated by the current electric valve action is greater than a specified value, it is determined that the current working state of the electric valve has experienced a long-term disturbance compared to the previous working state of the electric valve.

[0066] Furthermore, the diagnostic variable is compared with its threshold value to determine whether the electric valve has malfunctioned based on the relationship between the two values; this includes:

[0067] When the diagnostic variable includes current, the current is compared with the current threshold. If the current is greater than the current threshold, it is determined that a stalled rotor, a short circuit, or a severe jamming fault has occurred.

[0068] When the diagnostic variable includes power spectral entropy, the difference in power spectral entropy signals is compared with the power spectral entropy threshold. If the difference in power spectral entropy signals is greater than the power spectral entropy threshold, the valve is determined to be faulty.

[0069] When the diagnostic variable includes average power, the difference in the average power signal is compared with the average power threshold. If the difference in the average power signal is greater than the average power threshold, the valve is determined to be faulty. At this time, it is determined whether the difference in the current signal is greater than the threshold. If the difference in the current signal is greater than the threshold, the valve motor is determined to be stalled or stuck. Otherwise, a voltage fault is determined.

[0070] Furthermore, it also includes:

[0071] The fault diagnosis results are output in the form of level signals; if the level signal is high, it indicates that a fault has occurred; if the level signal is low, it indicates that no fault has occurred; if the level signal is the first fault level signal, it indicates that the valve is stuck; if the level signal is the second fault level signal, it indicates that the valve is short-circuited; if the level signal is the third fault level signal, it indicates that the valve power supply voltage is abnormal.

[0072] Furthermore, diagnostic variable standard signals for the electric valve are adaptively established based on its operating state; including:

[0073] The diagnostic variable signals generated by the switching action of the electric valve in the working state are stored as diagnostic variable standard signals;

[0074] The diagnostic variables include: X-axis vibration signal power spectral entropy, Y-axis vibration signal power spectral entropy, Z-axis vibration signal power spectral entropy, mean a-phase current, mean b-phase current, mean c-phase current, and average power.

[0075] Secondly, embodiments of the present invention include an electric valve fault diagnosis system, as referenced Figure 2 As shown, it includes:

[0076] The diagnostic variable standard signal generation unit is used to adaptively establish the diagnostic variable standard signal of the electric valve according to the working state of the electric valve.

[0077] The judgment unit is used to determine whether the current working state of the electric valve has changed compared to the previous working state of the electric valve. If so, the diagnostic variable standard signal of the electric valve is adaptively re-established according to the current working state of the electric valve.

[0078] The update unit is used to adaptively update the threshold of the diagnostic variable based on the standard signal of the diagnostic variable;

[0079] The acquisition unit is used to acquire diagnostic variables during the operation of the electric valve switching; and

[0080] The comparison and determination unit is used to compare the diagnostic variable with the diagnostic variable threshold to determine whether the electric valve has malfunctioned based on the relationship between the size of the diagnostic variable and the diagnostic variable threshold.

[0081] For example, an embodiment of the present invention provides an electric valve fault diagnosis device, the hardware of which mainly includes a sensor, a data acquisition system and a microprocessor system.

[0082] The sensors mainly include vibration sensors, current sensors, and power sensors. Vibration sensors include X-axis vibration sensors, Y-axis vibration sensors, and Z-axis vibration sensors; current sensors include a-phase current sensors, b-phase current sensors, and c-phase current sensors.

[0083] X-axis, Y-axis, and Z-axis vibration sensors are mounted on the valve body to measure the X-axis, Y-axis, and Z-axis vibration signals during valve operation, respectively. Phase a, phase b, and phase c current sensors are connected to the valve body's power supply line to measure the phase a, phase b, and phase c currents, respectively. A power sensor is used to measure the valve's power.

[0084] The data acquisition system connects to the sensors, collects and saves sensor data, and simultaneously transmits the data to the microprocessor system via data communication. The microprocessor system receives the data transmitted from the data acquisition system, runs a real-time fault diagnosis program, performs fault diagnosis, and finally outputs the fault diagnosis results in the form of level signals. A high level indicates a fault has occurred, while a low level indicates no fault has occurred. There are a total of three fault signal outputs: the first is a valve jamming fault signal, the second is a valve short-circuit fault signal, and the third is a valve power supply voltage abnormality signal. For detailed operating procedures, refer to [reference needed]. Figure 7 As shown.

[0085] The working logic of the electric valve fault diagnosis device is mainly as follows:

[0086] (1) First, taking each opening and closing of the valve as the research unit, three categories of parameter variables were selected as diagnostic variables: X-axis vibration signal power spectral entropy, Y-axis vibration signal power spectral entropy, Z-axis vibration signal power spectral entropy, a-phase current mean, b-phase current mean, c-phase current mean, and average power signal. First, a standard signal under valve health conditions was adaptively established, such as... Figure 3 The diagram shows the process of establishing the power spectral entropy standard signal. Figure 4 The process of establishing a standard three-phase current signal. Figure 5 The process of establishing the average power standard signal requires adaptive re-establishment of the standard signal if the operating conditions change or if long-term or short-term disturbances occur. Secondly, during valve operation, the power spectral entropy of the valve's three-axis vibration signal is calculated in real time, and the average effective value of the three-phase current and the average power signal are acquired and calculated in real time. Finally, the difference between the measured values ​​and the standard values ​​is calculated. If the difference exceeds a pre-set threshold, a fault is considered to have occurred, and the valve needs to be repaired.

[0087] (2) If the difference in power spectral entropy signals on the X, Y, or Z axes exceeds the threshold, a valve malfunction is considered, such as a jamming fault. The valve needs repair because the power spectral entropy value decreases when the valve is jammed. If the difference in current signals between phases A, B, and C exceeds the threshold, a short circuit fault is considered in phase A, B, and C. The controller immediately issues a power-off shutdown command. If the average power signal difference exceeds the threshold, the controller immediately issues a power-off shutdown command. At this time, it checks if the current signal difference exceeds the threshold. If the current signal difference exceeds the threshold, the valve motor is considered stalled or jammed. If the current signal difference does not exceed the threshold, the three-phase voltage has changed, and the distribution cabinet fault should be located immediately. Figure 6 This is a fault diagnosis model for electric valves.

[0088] Threshold selection principle:

[0089] (1) The three-phase current threshold should be the difference between the stalled current and the normal operating current. If the difference in current signals is greater than the threshold, it is considered that a stalled rotor, a line short circuit, or a severe jamming fault has occurred. The current threshold should be adaptively updated according to different operating conditions, long-term disturbances, and short-term disturbances.

[0090] (2) Due to varying degrees of jamming faults, the power spectrum entropy signal will change to different degrees. When a severe jamming fault occurs, the vibration signal changes significantly, and the power spectrum entropy difference will approach 0. Therefore, the threshold can be taken as a value close to the power spectrum entropy value during normal vibration. The power spectrum entropy threshold should be adaptively updated according to different operating conditions, long-term disturbances, and short-term disturbances.

[0091] (3) When selecting the threshold for the average power signal difference, the power variation characteristics should be fully considered, and it is advisable to select 2 to 3 times the normal power. The average power threshold should be adaptively updated according to different operating conditions, long-term disturbances, and short-term disturbances.

[0092] (4) Long-term disturbance analysis: To overcome the bias caused by long-term environmental noise disturbances on the measurement parameters, a long-term disturbance analysis method is proposed. The measurement parameters of the valve's three previous valve actions are taken and weighted. The weight of the third valve action before the current action is 0.4, the weight of the second valve action before the current action is 0.4, and the weight of the first valve action before the current action is 0.2. Based on these weights, the three valve actions before the disturbance are weighted. The weights are compared with the current measurement parameters. If the deviation is large, a disturbance is considered to have occurred. The threshold is then adaptively updated based on the magnitude of the deviation.

[0093] (5) Short-term disturbance analysis: To overcome the deviation of measurement parameters caused by instantaneous noise disturbances, an instantaneous disturbance analysis method is proposed. The measurement parameters of the valve's last operation before the current valve operation are taken and compared instantaneously with the current measurement parameters. The comparison step size is based on the sampling frequency. If some instantaneous values ​​show significant deviations, it is considered that an instantaneous disturbance or instantaneous deviation caused by sensor measurement has occurred. Then, based on the magnitude of the deviation, the standard parameters and thresholds are adaptively updated.

[0094] Thirdly, embodiments of the present invention provide a storage medium on which instructions are stored, and when the instructions are executed on a computer, the electric valve fault diagnosis method is performed.

[0095] Therefore, the embodiments of the present invention can monitor the valve status in real time, diagnose valve faults in real time, and provide fault signals; the embodiments of the present invention have adaptive characteristics, which can adaptively adjust the diagnostic standard variables and diagnostic thresholds, and can form more reliable diagnostic results; it can diagnose a variety of abnormal valve states, and does not depend on the size of the valve fault data.

[0096] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for diagnosing faults in an electric valve, characterized in that, include: The standard signals for diagnostic variables of electric valves are adaptively established based on their operating status. Determine whether the current working state of the electric valve has changed compared to the previous working state. If so, adaptively re-establish the standard signal of the diagnostic variable of the electric valve based on the current working state. The thresholds of diagnostic variables are adaptively updated based on the standard signals of the diagnostic variables. Obtain diagnostic variables during the operation of electric valve switching; Compare diagnostic variables with diagnostic variable thresholds to determine whether the electric valve has malfunctioned based on the relationship between the two values. The operating conditions of electric valves include long-term disturbances and instantaneous disturbances. The diagnostic variables include: X-axis vibration signal power spectral entropy, Y-axis vibration signal power spectral entropy, Z-axis vibration signal power spectral entropy, mean a-phase current, mean b-phase current, mean c-phase current, and / or average power. The adaptive updating of diagnostic variable thresholds based on diagnostic variable standard signals includes: Under the long-term disturbance working state, the measured parameters of the valve that have been operated more than twice before the current valve operation are weighted and calculated. The weighted calculation result is compared with the current measured parameter, and the threshold is adaptively updated according to the magnitude of the deviation found in the comparison. Under the operating state of instantaneous disturbance, the measured parameters of the valve's first action before the current valve action are taken and compared with the current measured parameters instantaneously. The threshold is adaptively adjusted based on the magnitude of the deviation found in the comparison.

2. The electric valve fault diagnosis method as described in claim 1, characterized in that, Determine whether the current operating state of the electric valve has changed compared to its previous operating state; including: Compare the diagnostic variables of a previous action of the electric valve with the diagnostic variables generated by the current action of the electric valve. If the difference between the diagnostic variables of a previous action of the electric valve and the diagnostic variables generated by the current action of the electric valve is greater than a specified value, it is determined that the working state of the current electric valve has experienced a short-term disturbance compared to the previous working state of the electric valve.

3. The electric valve fault diagnosis method as described in claim 2, characterized in that, Determine whether the current operating state of the electric valve has changed compared to its previous operating state; including: The diagnostic variables of the electric valve that have performed more than two actions before the current electric valve action are weighted and calculated to obtain a weighted value. Compare the weighted value with the diagnostic variable generated by the current electric valve action. If the difference between the weighted value and the diagnostic variable generated by the current electric valve action is greater than a specified value, it is determined that the current working state of the electric valve has experienced a long-term disturbance compared to the previous working state of the electric valve.

4. The electric valve fault diagnosis method according to any one of claims 1-3, characterized in that, Comparing diagnostic variables with diagnostic variable thresholds to determine whether the electric valve has malfunctioned based on the relationship between the two thresholds; including: When the diagnostic variable includes current, the current is compared with the current threshold. If the current is greater than the current threshold, it is determined that a stalled rotor, a short circuit, or a severe jamming fault has occurred. When the diagnostic variable includes power spectral entropy, the difference in power spectral entropy signals is compared with the power spectral entropy threshold. If the difference in power spectral entropy signals is greater than the power spectral entropy threshold, the valve is determined to be faulty. When the diagnostic variable includes average power, the difference in the average power signal is compared with the average power threshold. If the difference in the average power signal is greater than the average power threshold, the valve is determined to be faulty. At this time, it is determined whether the difference in the current signal is greater than the threshold. If the difference in the current signal is greater than the threshold, the valve motor is determined to be stalled or stuck. Otherwise, a voltage fault is determined.

5. The electric valve fault diagnosis method as described in claim 4, characterized in that, include: The fault diagnosis results are output in the form of a level signal; A high level signal indicates a fault has occurred, while a low level signal indicates no fault has occurred. If the level signal is the first fault level signal, it indicates that the valve is stuck. If the level signal is the second fault level signal, it indicates a valve short circuit fault; if the level signal is the third fault level signal, it indicates an abnormal valve power supply voltage.

6. An electric valve fault diagnosis system, characterized in that, Also includes: The diagnostic variable standard signal generation unit is used to adaptively establish the diagnostic variable standard signal of the electric valve according to the working state of the electric valve. The judgment unit is used to determine whether the current working state of the electric valve has changed compared to the previous working state of the electric valve. If so, the diagnostic variable standard signal of the electric valve is adaptively re-established according to the current working state of the electric valve. The update unit is used to adaptively update the threshold of the diagnostic variable based on the standard signal of the diagnostic variable; The acquisition unit is used to acquire diagnostic variables during the operation of the electric valve switch; and the comparison and judgment unit is used to compare the diagnostic variables with the diagnostic variable threshold, so as to determine whether the electric valve has malfunctioned based on the relationship between the diagnostic variables and the diagnostic variable threshold. The operating conditions of electric valves include long-term disturbances and instantaneous disturbances. The diagnostic variables include: X-axis vibration signal power spectral entropy, Y-axis vibration signal power spectral entropy, Z-axis vibration signal power spectral entropy, mean a-phase current, mean b-phase current, mean c-phase current, and / or average power. The adaptive updating of diagnostic variable thresholds based on diagnostic variable standard signals includes: Under the long-term disturbance working state, the measured parameters of the valve that have been operated more than twice before the current valve operation are weighted and calculated. The weighted calculation result is compared with the current measured parameter, and the threshold is adaptively updated according to the magnitude of the deviation found in the comparison. Under the operating state of instantaneous disturbance, the measured parameters of the valve's first action before the current valve action are taken and compared with the current measured parameters instantaneously. The threshold is adaptively adjusted based on the magnitude of the deviation found in the comparison.

7. A storage medium, characterized in that, The computer-readable storage medium stores instructions that, when executed on a computer, perform the electric valve fault diagnosis method as described in any one of claims 1-5.

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