CN114611633A - Health monitoring method of electromagnetic valve - Google Patents
Health monitoring method of electromagnetic valve Download PDFInfo
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- CN114611633A CN114611633A CN202210500346.2A CN202210500346A CN114611633A CN 114611633 A CN114611633 A CN 114611633A CN 202210500346 A CN202210500346 A CN 202210500346A CN 114611633 A CN114611633 A CN 114611633A
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F18/00—Pattern recognition
- G06F18/20—Analysing
- G06F18/23—Clustering techniques
- G06F18/232—Non-hierarchical techniques
- G06F18/2321—Non-hierarchical techniques using statistics or function optimisation, e.g. modelling of probability density functions
- G06F18/23213—Non-hierarchical techniques using statistics or function optimisation, e.g. modelling of probability density functions with fixed number of clusters, e.g. K-means clustering
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F16/00—Information retrieval; Database structures therefor; File system structures therefor
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- G06F16/24—Querying
- G06F16/245—Query processing
- G06F16/2458—Special types of queries, e.g. statistical queries, fuzzy queries or distributed queries
- G06F16/2474—Sequence data queries, e.g. querying versioned data
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F17/00—Digital computing or data processing equipment or methods, specially adapted for specific functions
- G06F17/10—Complex mathematical operations
- G06F17/18—Complex mathematical operations for evaluating statistical data, e.g. average values, frequency distributions, probability functions, regression analysis
Abstract
The invention relates to the field of health monitoring of mechanical equipment, and particularly discloses a health monitoring method of an electromagnetic valve, which comprises the steps of acquiring a characteristic sequence, standardizing the characteristic sequence, screening the characteristic sequence, calculating a health monitoring index according to monotonicity of all the characteristic sequences and judging the health condition of the electromagnetic valve according to the health index; the monitoring method provided by the invention obtains a weighted value based on the weighted Wasserstein distance, namely, the weighted value is used as a health index for comprehensively representing the electromagnetic valve at the moment.
Description
Technical Field
The invention relates to the field of health monitoring of mechanical equipment, in particular to a health monitoring method of an electromagnetic valve.
Background
In a liquid nitrogen supply system, an on-off electromagnetic valve is an important element, and the on-off electromagnetic valve has the advantages of accurate action, high automation degree and stable and reliable work. Various problems arise inevitably during use. Although the cost of the electromagnetic valve is low, the maintenance is not complicated only by replacing the electromagnetic valve, but the fault is not obvious and is difficult to detect at the initial stage of the fault, which brings serious problems, the product quality is influenced if the fault is light, and accidents may occur if the fault is heavy; solenoid valve monitoring is therefore essential. In the existing monitoring method, two indexes for measuring the similarity degree of distribution are adopted, namely KL Divergence (Kullback-Leibler Divergence) and JS Divergence (Jensen-Shannon Divergence); however, if the two distributions are far apart, with no overlap at all, then the KL divergence value is meaningless, while the JS divergence value is a constant in this case. This is fatal in the learning algorithm, which means that the gradient of this point is 0, i.e., the gradient disappears.
Disclosure of Invention
Therefore, in order to solve the above-mentioned disadvantages, the present invention proposes a solenoid health monitoring method based on weighted Wasserstein distance, using sensor data of a solenoid, for monitoring the health status of the solenoid.
Specifically, the health monitoring method of the electromagnetic valve comprises the following steps:
step one, acquiring a characteristic sequence, and directly taking a data sequence of sensor measurement data directly representing the electromagnetic valve as the characteristic sequence to obtain a characteristic sequence setWhereinNIs composed ofThe number of medium characteristic sequences;
step two, standardizing the characteristic sequences, eliminating the difference of the characteristic sequences, wherein the standardized formula is as follows:
whereinAndrespectively before and after standardizationiThe sequence of the characteristics is determined by the sequence of the characteristics,andare respectively the firstiMean and standard deviation of individual signature sequences;
step three, screening the characteristic sequences, and calculating by using a monotonicity formulaiGlobal monotonicity of individual feature sequencesRemoving the characteristic sequence of the sensor with little or no degradation tendency, wherein the monotonicity formula is as follows:
wherein the content of the first and second substances,, andare respectively the firstiA first of the characteristic sequencesjNumerical value andthe number of the individual values is,is the length of the sample;
step (ii) ofFourthly, according to the monotonicity of all the characteristic sequences, dividing the characteristic sequences into two types through K-means, selecting the characteristic sequences with larger monotonicity, and supposing that the screened characteristic sequences areWherein,RIs composed ofThe number of the characteristic sequences in the medium,the characteristic sequence with larger monotonicity is adopted;
step five, calculating a health monitoring index, and using the Wasserstein distance as the health index;
Step six, according to the health indexesAnd judging the health condition of the electromagnetic valve.
Preferably, the specific method of the fifth step is to perform characteristic sequenceRespectively selecting the length of the sequence from each characteristic sequence from the initial timeA sequence of (2) as a reference sequence, denotedThe characteristic sequence at the t-th moment is recorded as,
Respectively obtained by nuclear density estimationThe probability density function of the reference sequence and the characteristic sequence at the t-th moment and the probability density function are calculated through a formulaCalculating a reference sequenceProbability density function corresponding to reference sequence and characteristic sequence at t-th momentWasserstein distance between corresponding probability density functions;
By the formulaWeighting the Wasserstein distances calculated by all the characteristic sequences, namely, the weighted Wasserstein distances are used as the health indexes for comprehensively representing the electromagnetic valve at the momentWhereinIs the firstjA characteristic sequence oftThe weight of the time of day.
In this invention, the Wasserstein distance is a measure of the distance between two probability distributions, and is defined as:
in the formula: wherein the content of the first and second substances,andis the first of two probability density functionskA value;is a distance measure;r is the order of the figure. The distance between Wasserstein and the two probability density functions is in the gaprIntegral at order index.
The invention has the following advantages:
the monitoring method provided by the invention obtains a weighted value based on the weighted Wasserstein distance, namely the weighted value is used as a health index for comprehensively representing the electromagnetic valve at the momentThe monitoring method provided by the invention is less influenced by the number of the sensors, the range of the health evaluation value is not influenced by data difference in the system, and the accurate health condition of the electromagnetic valve is provided for working personnel so as to provide a better maintenance scheme.
Drawings
FIG. 1 is a schematic flow diagram of the process of the present invention.
Detailed Description
The present invention will be described in detail with reference to the accompanying drawing 1, and the technical solutions in the embodiments of the present invention will be clearly and completely described.
A health monitoring method of an electromagnetic valve comprises the following steps:
step one, obtaining a characteristic sequence, extracting characteristics of time domain, frequency domain, energy, entropy and the like of sensor data of the electromagnetic valve and using the characteristics as the characteristic sequence to obtain a characteristic sequence setIn whichNIs composed ofNumber of medium signature sequences.
Step two, standardizing the characteristic sequence data,
because data of each sensor in the electromagnetic valve have certain difference, the invention carries out standardization processing on the characteristic sequence through a standardization formula to eliminate the data difference, wherein the standardization formula is as follows:
whereinAndrespectively before and after standardizationiThe characteristic sequences are arranged in a sequence of the characteristic,andare respectively the firstiMean and standard deviation of individual signature sequences.
Step three, screening the characteristic sequences
In order to reduce the amount of calculation, the sensor parameter signature sequence with little or no degradation tendency is removed. The common method is to select useful characteristic sequence manually by directly observing the variation trend of the characteristic sequence, and the method has certain subjectivity. In this respect, the present invention uses a monotonicity formula to calculateiGlobal monotonicity of individual characteristic sequencesThe formula for monotonicity is as follows:
wherein the content of the first and second substances,, andare respectively the firstiA first of the characteristic sequencesjNumerical value andthe number of the individual values is,is the length of the sample.The larger the monotonicity, the stronger the monotonicity, and conversely, the weaker the monotonicity. If it is firstiThe sequence of individual features is completely monotonic,is 1; if it is firstiThe sequence of individual features is non-monotonic,is 0.
And step four, dividing the characteristic sequences into two types through K-means according to the monotonicity of all the characteristic sequences, and selecting the characteristic sequence with larger monotonicity. The sequence of the screened features is assumed to be:wherein,RIs composed ofThe number of the characteristic sequences in the medium,the characteristic sequence with larger monotonicity is obtained. At this time, the characteristic sequences obtained after screening all have a certain tendency of degeneration.
Step five, calculating health monitoring indexes
In the invention, the Wasserstein distance is used for calculating the health index, and the Wasserstein distance is used in the characteristic sequenceRespectively selecting the length of the sequence from each characteristic sequence from the initial timeA sequence of (2) as a reference sequence, denoted;
In order to calculate the Wasserstein distance at time t relative to the initial time, the length of the Wasserstein distance at time t needs to be selectedAnd a reference sequenceThe Wasserstein distance is calculated. Wherein the characteristic sequence at the t-th time is represented as;
Respectively obtaining probability density functions of the reference sequence and the characteristic sequence at the t-th moment through kernel density estimation, and obtaining the probability density functions through a formulaCalculating a reference sequenceProbability density function corresponding to reference sequence and characteristic sequence at t-th momentThe Wasserstein distance between the probability density functions corresponding to the characteristic sequences at the t-th time。
Because each characteristic sequence can represent the health degree of the system at a certain momentTherefore, the Wasserstein distance calculated for all the characteristic sequences is formulatedWeighting to obtain a weighted value as a health index of the solenoid valve(ii) a Wherein the content of the first and second substances,is the firstjA characteristic sequence oftThe weight of the time of day.
Step six, according to the health indexesThe method for judging the health condition of the electromagnetic valve comprises the following steps:
the idea of confidence interval in statistics is adopted to design self-adaptive threshold value and health indexThe mean and variance of (a) are:and(ii) a According to health indexThe distribution condition of (2) needs to set an upper limit value and a lower limit value; meanwhile, the health index can be under the condition of no fault due to noise disturbance in the actual operation processIs not 0, so a constant is introducedTo improve the robustness of the threshold; therefore, according to the health indexThe mean and variance of (c) determine the following thresholds:
wherein the content of the first and second substances,is the upper limit value of the number of bits,is the lower limit value;is a constant.
The logic for judging whether the electromagnetic valve is healthy is as follows:
wherein the content of the first and second substances,is a health indicator obtained from the latest sequence.
The method monitors the health of the electromagnetic valve by utilizing the sensor data of the electromagnetic valve and based on the weighted Wasserstein distance, is less influenced by the number of the sensors, and the range of the health evaluation value is not influenced by the data difference in the system.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (3)
1. A health monitoring method of an electromagnetic valve is characterized by comprising the following steps:
s1, acquiring a characteristic sequence, and directly taking a data sequence of sensor measurement data directly representing the electromagnetic valve as the characteristic sequence to obtain a characteristic sequence set;
s2, standardizing the characteristic sequences and eliminating the difference of the characteristic sequences;
s3, screening the characteristic sequences, calculating the integral monotonicity of the characteristic sequences by adopting a monotonicity formula, and removing the characteristic sequences which are not degraded;
s4, dividing the characteristic sequences into two types through K-means according to the monotonicity of all the characteristic sequences, and selecting the characteristic sequence with larger monotonicity;
s5, calculating a health monitoring index, and using the Wasserstein distance as the health index;
and S6, judging the health condition of the electromagnetic valve according to the health indexes.
2. The health monitoring method of the electromagnetic valve according to claim 1, wherein the specific method for calculating the health monitoring index is as follows:
in the feature sequences, a sequence with a specified length from an initial time is selected from each feature sequence as a reference sequence, probability density functions of the reference sequence and the feature sequences at corresponding times are obtained through kernel density estimation, Wassertein distances between the probability density functions corresponding to the reference sequences in the reference sequence and the probability density functions corresponding to the feature sequences at corresponding times are calculated, and the Wassertein distances are used for health indexes.
3. The health monitoring method of the electromagnetic valve according to claim 2, wherein the specific method for judging the health condition of the electromagnetic valve according to the health index is as follows: designing an adaptive threshold by adopting the idea of confidence interval in statistics; setting an upper limit value and a lower limit value by combining the mean value and the variance of the health indexes according to the distribution condition of the health indexes;
when the health index obtained by the latest sequence is greater than the upper limit value or less than the lower limit value, the fault is detected;
and when the health index obtained by the latest sequence is greater than or equal to the lower limit value and less than or equal to the upper limit value, determining that the health index is not in fault.
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Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN115310561A (en) * | 2022-09-29 | 2022-11-08 | 中国空气动力研究与发展中心设备设计与测试技术研究所 | Electromagnetic valve fault monitoring method based on integrated instant learning |
Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN106446540A (en) * | 2016-09-20 | 2017-02-22 | 华北电力大学(保定) | Real-time evaluation method for health state of wind turbine unit |
CN109000924A (en) * | 2018-10-24 | 2018-12-14 | 哈工大机器人(山东)智能装备研究院 | A kind of ball screw assembly, state monitoring method based on K mean value |
CN111090050A (en) * | 2020-01-21 | 2020-05-01 | 合肥工业大学 | Lithium battery fault diagnosis method based on support vector machine and K mean value |
CN112434636A (en) * | 2020-12-03 | 2021-03-02 | 西安交通大学 | Machine tool part health state monitoring method and system |
US20210184958A1 (en) * | 2019-12-11 | 2021-06-17 | Cisco Technology, Inc. | Anomaly detection of model performance in an mlops platform |
CN113569903A (en) * | 2021-06-09 | 2021-10-29 | 西安电子科技大学 | Method, system, equipment, medium and terminal for predicting abrasion of numerical control machine tool cutter |
CN113705738A (en) * | 2021-08-31 | 2021-11-26 | 长安大学 | Engineering equipment bearing degradation assessment method |
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Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN106446540A (en) * | 2016-09-20 | 2017-02-22 | 华北电力大学(保定) | Real-time evaluation method for health state of wind turbine unit |
CN109000924A (en) * | 2018-10-24 | 2018-12-14 | 哈工大机器人(山东)智能装备研究院 | A kind of ball screw assembly, state monitoring method based on K mean value |
US20210184958A1 (en) * | 2019-12-11 | 2021-06-17 | Cisco Technology, Inc. | Anomaly detection of model performance in an mlops platform |
CN111090050A (en) * | 2020-01-21 | 2020-05-01 | 合肥工业大学 | Lithium battery fault diagnosis method based on support vector machine and K mean value |
CN112434636A (en) * | 2020-12-03 | 2021-03-02 | 西安交通大学 | Machine tool part health state monitoring method and system |
CN113569903A (en) * | 2021-06-09 | 2021-10-29 | 西安电子科技大学 | Method, system, equipment, medium and terminal for predicting abrasion of numerical control machine tool cutter |
CN113705738A (en) * | 2021-08-31 | 2021-11-26 | 长安大学 | Engineering equipment bearing degradation assessment method |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN115310561A (en) * | 2022-09-29 | 2022-11-08 | 中国空气动力研究与发展中心设备设计与测试技术研究所 | Electromagnetic valve fault monitoring method based on integrated instant learning |
CN115310561B (en) * | 2022-09-29 | 2022-12-20 | 中国空气动力研究与发展中心设备设计与测试技术研究所 | Electromagnetic valve fault monitoring method based on integrated instant learning |
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