Hydraulic control one-way valve fault information acquisition method for hydraulic support

Abstract

The invention relates to the technical field of data processing, in particular to a hydraulic control one-way valve fault information acquisition method for a hydraulic support, and the method comprises the steps: recording an oil inlet and an oil outlet of a to-be-detected hydraulic control one-way valve as oil ports, respectively obtaining the pressure of each oil port at all moments in a pressure increasing time period and a pressure maintaining time period, recording the signals as boosting section signals and pressure maintaining section signals of each oil port; determining the signal similarity of any modal component; obtaining a de-noised boosting section signal of each oil port; obtaining a pressure boosting evaluation value of each oil port; obtaining the denoised pressure maintaining section signal of each oil port; determining a pressure maintaining evaluation value of each oil port; the fault degree of the to-be-detected hydraulic control one-way valve is obtained, and the leakage fault of the to-be-detected hydraulic control one-way valve is evaluated. The early weak leakage fault information hidden in the to-be-detected hydraulic control one-way valve can be monitored in time, and the risk of safety accidents of the hydraulic support is reduced.

Description

Technical Field

[0001] The present application relates to the field of data processing technology, and in particular to a method for collecting fault information of a hydraulically controlled one-way valve for a hydraulic support. Background Art

[0002] The hydraulic support is a structure used to control the mine pressure at the coal mining face, and plays an important protective role in underground coal mining. The hydraulically controlled one-way valve is an important control element in the hydraulic support. Its sealing performance plays a role in maintaining pressure and positioning in the hydraulic support. A slight leakage in the hydraulically controlled one-way valve will cause the hydraulic cylinder to shift in position. Severe leakage may make the hydraulic support prone to safety accidents.

[0003] Existing hydraulically controlled one-way valves usually collect their pressure signals and use abnormal data in the pressure signals to determine whether the hydraulically controlled one-way valve is leaking. However, the leakage fault signal in the hydraulic system is a typical weak signal under strong background noise, which makes it difficult to effectively extract early weak leakage fault information by directly collecting abnormal data on the pressure of the hydraulically controlled one-way valve, and thus cannot be monitored in time when an early weak leakage fault occurs in the hydraulically controlled one-way valve. Summary of the invention

[0004] In order to solve the above technical problems, a method for collecting fault information of a hydraulically controlled one-way valve for a hydraulic support is provided to solve the existing problems.

[0005] The solution to the technical problem of the present application is to provide a method for collecting fault information of a hydraulically controlled one-way valve for a hydraulic support, comprising the following steps:

[0006] The oil inlet and the oil outlet of the hydraulically controlled one-way valve to be tested are recorded as each oil port, and the pressure of each oil port at all times during the pressure-increasing period and the pressure-maintaining period are respectively obtained, which are recorded as the pressure-increasing section signal and the pressure-maintaining section signal of each oil port;

[0007] Extract the signals with trend items and the signals with trend elimination items from the boost section signals of each oil port; perform modal decomposition on the signals with trend elimination items, analyze the similarity of signals in different time periods in any modal component corresponding to the signals with trend elimination items in the frequency domain, and determine the signal similarity of any modal component; based on the signal similarity, perform signal reconstruction after filtering the modal components, and obtain the boost section signals of each oil port after denoising in combination with the signals with trend items;

[0008] Based on the change trend of the boost section signal of each oil port after denoising, the boost evaluation value of each oil port is obtained;

[0009] Perform modal decomposition on the pressure holding section signal of each oil port, analyze the correlation characteristics of each modal component corresponding to the pressure holding section signal of each oil port, screen all modal components and reconstruct the signal to obtain the denoised pressure holding section signal of each oil port;

[0010] The pressure holding evaluation value of each oil port is determined by the distribution of the pressure holding section signal of each oil port after denoising in the frequency domain;

[0011] Based on the pressure increase evaluation value and the pressure maintenance evaluation value of all oil ports, the fault degree of the hydraulically controlled one-way valve to be tested is obtained, and the leakage fault of the hydraulically controlled one-way valve to be tested is evaluated.

[0012] Preferably, a signal trend elimination method is adopted to extract a signal with a trend term and a signal with a trend elimination term from the boost section signal of each oil port.

[0013] Preferably, the determining the signal similarity of any modal component comprises:

[0014] Divide any modal component into multiple signal segments; perform frequency domain analysis on each signal segment to obtain a frequency spectrum of each signal segment;

[0015] The signal similarity is the average of the similarities of the frequency spectrograms corresponding to all any two signal segments in any modal component.

[0016] Preferably, the process of acquiring the boost section signal after denoising of each oil port is as follows:

[0017] Obtaining a segmentation threshold of signal similarity of all modal components corresponding to the signal for eliminating the trend term, recorded as a first segmentation threshold; performing signal reconstruction on all modal components of each oil port whose signal similarity is greater than the first segmentation threshold;

[0018] The amplitude of the reconstructed signal and the signal with trend term at the same time are added to obtain the boost section signal of each oil port after denoising.

[0019] Preferably, the boost assessment value is the slope of a fitted straight line obtained by linearly fitting the boost section signals of each oil port after denoising.

[0020] Preferably, a further measurement method of the correlation feature is: calculating the autocorrelation coefficient of each modal component corresponding to the pressure-holding section signal of each oil port.

[0021] Preferably, the process of acquiring the pressure holding section signal after denoising of each oil port is as follows:

[0022] Obtaining the segmentation threshold of the autocorrelation coefficients of all modal components corresponding to the pressure-maintaining section signals of each oil port, recorded as the second segmentation threshold;

[0023] Signal reconstruction is performed on all modal components of each oil port whose autocorrelation coefficient is greater than the second segmentation threshold to obtain a denoised pressure holding section signal of each oil port.

[0024] Preferably, determining the pressure maintenance evaluation value of each oil port includes:

[0025] The denoised pressure holding signals of each oil port are subjected to frequency domain analysis to obtain a spectrum diagram, and the cumulative sum of the products between all frequency components in the spectrum diagram and their corresponding energies is taken as the pressure holding evaluation value of each oil port.

[0026] Preferably, obtaining the fault degree of the hydraulically controlled one-way valve to be tested includes:

[0027] The pressure increase evaluation values ​​and pressure maintenance evaluation values ​​of all oil ports of the hydraulically controlled one-way valve to be tested are used to form a fault evaluation vector;

[0028] Obtain the pressure-rising section signal and the pressure-maintaining section signal of each oil port in the hydraulically-controlled one-way valve without leakage in the historical period, and calculate the pressure-rising evaluation value and the pressure-rising evaluation value of each oil port in the hydraulically-controlled one-way valve without leakage, and form them into a historical reference vector;

[0029] The difference between the fault assessment vector and the historical reference vector is calculated as the fault degree of the hydraulically controlled one-way valve to be tested.

[0030] Preferably, the step of evaluating the leakage fault of the hydraulically controlled one-way valve to be tested includes:

[0031] If the fault degree is greater than a preset threshold, the hydraulically controlled one-way valve to be tested has a leakage fault; otherwise, the hydraulically controlled one-way valve to be tested does not have a leakage fault.

[0032] This application has at least the following beneficial effects:

[0033] The present application extracts the signal of eliminating the trend item from the boost section signal of each oil port in the tested hydraulic control one-way valve, analyzes the similar change characteristics of the signal of the eliminated trend item under different frequency components, and calculates the signal similarity of any modal component. The beneficial effect is that after eliminating the trend of the boost section signal, it is determined whether the signal at the frequency corresponding to the modal component has similarity to reflect the possibility that the modal component is a noise signal component; secondly, through the signal similarity, the modal component of the noise signal is eliminated, the signal of the remaining modal components is reconstructed, and the signal is fused with the trend item signal to obtain the boost section signal of each oil port after denoising, and the boost evaluation value of each oil port is obtained. The beneficial effect is that compared with the existing denoising algorithm, it effectively avoids the possibility that the real signal trend in the boost section signal is mistakenly regarded as noise and mistakenly removed during the denoising process, and improves the accuracy of the subsequent evaluation of the change trend of the boost section signal after denoising, thereby more accurately and effectively extracting the potential leakage fault information of the hydraulic control one-way valve during its boost process; analyzing the pressure holding section of each oil port in the tested hydraulic control one-way valve The autocorrelation of the signal in different modal components is used to eliminate the modal components without autocorrelation characteristics, thereby eliminating the modal components containing noise components, and reconstructing the signals of the remaining modal components to obtain the denoised pressure holding section signals of each oil port. The beneficial effect is that the influence of the noise in the pressure holding section signals on the subsequent evaluation of the weak leakage fault information hidden in the pressure holding section signals is reduced; the pressure holding evaluation value of each oil port is determined by performing frequency domain analysis on the denoised pressure holding section signals of each oil port, which has the beneficial effect of being able to more accurately and effectively extract the denoised pressure holding section signals. The potential leakage fault information in the pressure-maintaining section signal after noise is obtained; the fault degree of the hydraulically controlled one-way valve to be tested is obtained through the pressure-increasing evaluation value and the pressure-maintaining evaluation value of all oil ports of the hydraulically controlled one-way valve to be tested, and the leakage fault of the hydraulically controlled one-way valve to be tested is evaluated. The beneficial effect is that the hydraulically controlled one-way valve to be tested can be compared with the hydraulically controlled one-way valve without leakage, so that the early weak leakage fault information hidden in the hydraulically controlled one-way valve to be tested can be effectively monitored, and then the leakage fault of the hydraulically controlled one-way valve to be tested can be handled in time, thereby reducing the risk of safety accidents of hydraulic supports. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The following is a further detailed description of a method for collecting fault information of a hydraulically controlled one-way valve for a hydraulic support of the present application in conjunction with the accompanying drawings.

[0035] Figure 1 A flowchart of the steps of a method for collecting fault information of a hydraulically controlled one-way valve for a hydraulic support provided in an embodiment of the present application;

[0036] Figure 2 A flowchart of the steps of a method for obtaining a pressure maintenance evaluation value of each oil port provided in an embodiment of the present application;

[0037] Figure 3A flowchart of the steps of a method for obtaining a fault degree provided in an embodiment of the present application. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solution and advantages of this application more clear, the following is a further detailed description of a method for collecting fault information of a hydraulically controlled one-way valve for a hydraulic support proposed in this application in combination with the accompanying drawings and implementation examples. It should be understood that the specific embodiments described herein are only used to explain this application and are not used to limit this application.

[0039] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0040] See also Figure 1 , which shows a flowchart of a method for collecting fault information of a hydraulically controlled one-way valve for a hydraulic support provided by an embodiment of the present application, the method comprising the following steps:

[0041] Step 1: record the oil inlet and outlet of the hydraulically controlled one-way valve to be tested as each oil port, obtain the pressure of each oil port at all times during the pressure boosting period and the pressure maintaining period, and record them as the pressure boosting section signal and the pressure maintaining section signal of each oil port.

[0042] In hydraulic systems, hydraulically controlled check valves are a commonly used directional control valve in hydraulic systems. They are mainly used to prevent reverse flow of oil in hydraulic systems. Hydraulically controlled check valves are often used for short-term pressure maintenance and locking of hydraulic working circuits. When two hydraulically controlled check valves are used together, the function of interlocking the two working circuits can be achieved.

[0043] The hydraulically controlled one-way valve is prone to failure and affects the normal operation of the coal mining machine. Among them, the leakage of the hydraulically controlled one-way valve will have a certain impact on the performance of the coal mining machine. The cause of the one-way valve leakage is generally caused by sealing problems, such as damage to the oil hole sealing ring, damage to the sealing surface connected to the oil circuit, improper selection of the sealing ring, and unreasonable sealing form.

[0044] In order to detect whether the hydraulic control one-way valve has leakage, a pressure sensor is installed before and after the hydraulic control one-way valve in the hydraulic support to be tested, and the pressure of the oil inlet and outlet of the hydraulic control one-way valve to be tested at different times during the pressure increase period and the pressure maintenance period is collected;

[0045] The pressures of the oil inlet of the hydraulically controlled one-way valve to be tested at all times during the pressure-increasing period and the pressure-maintaining period are recorded as the pressure-increasing section signal and the pressure-maintaining section signal of the oil inlet;

[0046] The pressure of the oil outlet of the hydraulically controlled one-way valve to be tested at all times during the pressure-rising period and the pressure-maintaining period are recorded as the pressure-rising section signal and the pressure-maintaining section signal of the oil outlet.

[0047] In this embodiment, the acquisition frequency of the pressure sensor is set to 1KHz, wherein the acquisition duration of the pressure holding section signal is set to 8s. As other implementation methods, the implementer can set them according to actual conditions, and this embodiment does not impose any special restrictions on this.

[0048] At this point, the pressure-rising section signal and the pressure-maintaining section signal of the oil inlet of the hydraulically controlled one-way valve to be tested, as well as the pressure-rising section signal and the pressure-maintaining section signal of the oil outlet are obtained.

[0049] Step 2, extracting the signal with trend item and the signal with trend item eliminated from the boost section signal of each oil port; performing modal decomposition on the signal with trend item eliminated, analyzing the similarity of signals in different time periods in any modal component corresponding to the signal with trend item eliminated in the frequency domain, and determining the signal similarity of any modal component; based on the signal similarity, reconstructing the signal after filtering the modal components, and obtaining the boost section signal of each oil port after denoising in combination with the signal with trend item; obtaining the boost evaluation value of each oil port based on the changing trend of the boost section signal of each oil port after denoising.

[0050] Due to the noise interference in the process of collecting and transmitting pressure data, some useful information features will be covered. When the hydraulic control one-way valve has an early weak leakage caused by the wear or tear of its valve core and sealing ring, it is difficult to detect such early weak leakage fault by monitoring the abnormal pressure data in the control chamber of the hydraulic control one-way valve. However, this early weak leakage will slow down the pressure increase speed of the pressure in the control chamber of the hydraulic control one-way valve during its pressure increase process, which is smaller than the pressure increase speed of the hydraulic control one-way valve without leakage during its pressure increase process; and the greater the leakage degree of this early weak leakage fault, the smaller the pressure increase speed during the pressure increase process. However, the pressure collected during the pressure increase process cannot accurately evaluate the pressure increase rate of the pressure increase process due to the mixing of noise signals, which leads to the inability to effectively extract the leakage information carried by the pressure of the hydraulic control one-way valve during the pressure increase process.

[0051] Secondly, since the pressure data of the hydraulically controlled one-way valve has an obvious upward trend during the boost process, the traditional denoising algorithm will mistake some real change trends in the pressure data as noise during the denoising process and remove them incorrectly, which will affect the subsequent evaluation accuracy of the change trend of the denoised pressure data. Therefore, after eliminating the trend in the boost signal, the noise information contained therein is analyzed and the noise in the signal is removed. The specific process is as follows:

[0052] The oil inlet and outlet of the hydraulically controlled one-way valve to be tested are recorded as the oil ports;

[0053] The signal trend elimination method is adopted to extract the signal with trend item and the signal with trend elimination item from the boost section signal of each oil port.

[0054] In this embodiment, a method for eliminating trend items based on the least squares method is adopted, wherein the method for eliminating trend items based on the least squares method is a well-known technology and will not be described in detail here. As other implementation methods, implementers can adopt other methods of the prior art, for example, a method for eliminating trend items based on a Sgolay filter, etc. This embodiment does not impose any special restrictions on this.

[0055] During the pressure-boosting process of the hydraulically controlled one-way valve, the control pressure oil will enter the control chamber of the hydraulically controlled one-way valve from the control port to push the valve core to move. During this pressure-boosting process, the valve core movement of the hydraulically controlled one-way valve is usually continuous and in the same direction. Secondly, the control pressure of the valve core will gradually increase during the pressure-boosting process, and the movement of the valve core is relatively smooth, so that the pressure data collected during the pressure-boosting process has similar signal frequency distribution in different time periods, and noise usually destroys this distribution due to its time-varying characteristics.

[0056] Therefore, the similarity of the frequency characteristics of the signal with the trend term eliminated is analyzed and the signal similarity is calculated, specifically:

[0057] Perform modal decomposition on the signal with trend term eliminated to obtain multiple modal components;

[0058] In this embodiment, a variational modal decomposition algorithm is used for modal decomposition, wherein the variational modal decomposition algorithm is a well-known technology and will not be described in detail here; secondly, the number of modal components is 10, as other implementation methods, the implementer can set it according to actual conditions.

[0059] Splitting each modal component corresponding to the trend-eliminated signal into a plurality of signal segments;

[0060] In this embodiment, each modal component corresponding to the signal from which the trend term is eliminated is evenly divided into 8 signal segments. As other implementation methods, implementers can set them according to actual conditions.

[0061] Perform frequency domain analysis on each signal segment to obtain a spectrum diagram of each signal segment;

[0062] In this embodiment, fast Fourier transform is used to perform frequency domain analysis to obtain a spectrum diagram, wherein fast Fourier transform is a well-known technology and will not be described in detail here. As other implementation methods, implementers can adopt other methods of the existing technology, such as discrete Fourier transform, etc. This embodiment does not impose any special restrictions on this.

[0063] It should be noted that in the spectrum diagram, the horizontal axis represents frequency and the vertical axis represents energy. Therefore, each frequency corresponds to an energy. By recording each frequency as a frequency component, the energy corresponding to each frequency component can be obtained.

[0064] The average of the similarities of the frequency spectra corresponding to any two signal segments in each modal component corresponding to the signal of the eliminated trend item is used as the signal similarity of each modal component corresponding to the signal of the eliminated trend item;

[0065] In this embodiment, the degree of similarity is measured by calculating the cosine similarity of the energy of all frequency components in the spectrum diagram corresponding to any two signal segments, wherein the calculation of cosine similarity is a well-known technology and will not be repeated here. As other implementation methods, implementers can adopt other methods of the prior art, such as the Pearson correlation coefficient, etc., and this embodiment does not impose any special restrictions on this.

[0066] It should be noted that the smaller the signal similarity is, the less likely the pressure data of the modal component has similar frequency distribution characteristics in different time periods, which means that the modal component is more likely to be a noise signal component in the signal with the trend term eliminated.

[0067] Further, based on the signal similarity, the noise signal components are screened to remove the noise signal, specifically:

[0068] Obtaining a segmentation threshold of signal similarity of all modal components corresponding to the signal eliminating the trend term, recorded as a first segmentation threshold;

[0069] In this embodiment, the Otsu threshold segmentation algorithm is used to obtain the first segmentation threshold, wherein the Otsu threshold segmentation algorithm is a well-known technology and will not be described in detail here. As other implementation methods, the implementer can adopt other methods of the prior art, such as cross-validation method, etc. This embodiment does not impose any special restrictions on this.

[0070] Signal reconstruction is performed on all modal components whose signal similarity is greater than the first segmentation threshold, and the amplitude of the reconstructed signal and the signal with the trend term at the same time are added to obtain the boost section signal of each oil port after denoising.

[0071] It should be noted that the signal reconstruction process is a well-known technology and will not be described in detail here.

[0072] The slope of the fitted straight line after performing linear fitting on the boost section signal of each oil port after denoising is used as the boost evaluation value of each oil port;

[0073] In this embodiment, the least square method is used for linear fitting, wherein the least square method is a well-known technology and will not be described in detail here.

[0074] It should be noted that the pressure boost evaluation value reflects the change in the pressure boost speed of the oil inlet and oil outlet during the pressure boost process, and is used to evaluate the degree of early weak leakage fault information carried by the pressure data of the oil inlet and oil outlet of the hydraulically controlled one-way valve to be tested during the pressure boost process. The larger the pressure boost evaluation value, the faster the pressure boost speed of the oil inlet and oil outlet during the pressure boost process, and the greater the difference between the pressure boost evaluation value and the hydraulically controlled one-way valve in the non-leakage period, the greater the possibility of a leakage fault in the hydraulically controlled one-way valve to be tested.

[0075] At this point, the pressure increase evaluation values ​​of the oil inlet and oil outlet of the hydraulically controlled one-way valve to be tested are obtained.

[0076] Step 3: perform modal decomposition on the pressure-holding section signal of each oil port, analyze the correlation characteristics of each modal component corresponding to the pressure-holding section signal of each oil port, screen all modal components, and reconstruct the signal to obtain the denoised pressure-holding section signal of each oil port; determine the pressure-holding evaluation value of each oil port through the distribution of the denoised pressure-holding section signal of each oil port in the frequency domain.

[0077] Furthermore, during the normal operation of the hydraulic control one-way valve, the pressure in the control chamber is usually stable, so that the pressure change of the hydraulic control one-way valve during the pressure maintenance process is relatively stable, that is, it has a small signal frequency and fluctuation amplitude. If the hydraulic control one-way valve leaks, the pressure in the control chamber of the hydraulic control one-way valve will slowly drop due to the leakage. When the pressure drops to a certain value, the pressure gauge in the pressure maintenance circuit will trigger a signal to make the hydraulic pump resume oil supply to the control chamber to increase the pressure to maintain the pressure in the control chamber. After the hydraulic pump stops supplying oil, the pressure will drop again, causing the pressure waveform of the hydraulic control one-way valve during its pressure maintenance process to fluctuate approximately periodically. The more serious the leakage, the faster the degree and speed of the pressure drop, the higher the oil supply frequency, and the greater the frequency and amplitude of the pressure signal. However, during the pressure maintenance process, the pressure will be affected by noise, which will cover up the pressure change characteristics caused by the early weak leakage failure of the hydraulic control one-way valve. Therefore, it is necessary to denoise the pressure data during the pressure maintenance process.

[0078] Based on the above analysis, the pressure data of the hydraulically controlled one-way valve has a strong autocorrelation during the pressure holding process, while the noise has no autocorrelation due to its randomness and complexity. Therefore, the autocorrelation characteristics of the pressure holding section signal are analyzed, the noise signal component is eliminated, and the pressure holding evaluation value is calculated. The step flow chart of the method for obtaining the pressure holding evaluation value of each oil port provided in the embodiment of the present application is as follows: Figure 2 As shown, specifically including:

[0079] Perform modal decomposition on the pressure holding section signal of each oil port to obtain multiple modal components;

[0080] In this embodiment, a variational modal decomposition algorithm is used for modal decomposition, wherein the variational modal decomposition algorithm is a well-known technology and will not be described in detail here; secondly, the number of modal components is 10, as other implementation methods, the implementer can set it according to actual conditions.

[0081] Calculate the autocorrelation coefficient of each modal component;

[0082] In this embodiment, when calculating the autocorrelation coefficient, the delay amount is set to 3. As other implementation methods, the implementer can set it according to the actual situation. Among them, the calculation of the autocorrelation coefficient is a well-known technology and will not be repeated here.

[0083] It should be noted that the smaller the autocorrelation coefficient is, the weaker the autocorrelation of the modal component is, and the more likely it is a noise component.

[0084] Obtaining the segmentation threshold of the autocorrelation coefficients of all modal components corresponding to the pressure-maintaining section signals of each oil port, recorded as the second segmentation threshold;

[0085] In this embodiment, the Otsu threshold segmentation algorithm is used to obtain the second segmentation threshold, wherein the Otsu threshold segmentation algorithm is a well-known technology and will not be described in detail here. As other implementation methods, the implementer can adopt other methods of the prior art, such as the cross-validation method, etc. This embodiment does not impose any special restrictions on this; secondly, the process of signal reconstruction is a well-known technology and will not be described in detail here.

[0086] Performing signal reconstruction on all modal components of each oil port whose autocorrelation coefficient is greater than the second segmentation threshold, to obtain a denoised pressure holding section signal of each oil port;

[0087] It should be noted that the signal reconstruction method is a well-known technology and will not be described in detail here.

[0088] Perform frequency domain analysis on the pressure holding signals of each oil port after denoising to obtain a spectrum diagram, and take the cumulative sum of the products between all frequency components in the spectrum diagram and their corresponding energies as the pressure holding evaluation value of each oil port;

[0089] In this embodiment, fast Fourier transform is used to perform frequency domain analysis, wherein fast Fourier transform is a well-known technology and will not be described in detail here.

[0090] It should be noted that the pressure holding evaluation value reflects the degree of early weak leakage fault information represented by the pressure data of the oil inlet and oil outlet of the hydraulically controlled one-way valve to be tested during the pressure holding process. The greater the difference between the pressure holding evaluation value and the hydraulically controlled one-way valve in the non-leakage period, the greater the possibility of a leakage fault in the hydraulically controlled one-way valve to be tested, and the more early weak leakage fault information is contained in the pressure holding section signal.

[0091] At this point, the pressure maintenance evaluation values ​​of the oil inlet and oil outlet of the hydraulically controlled one-way valve to be tested are obtained.

[0092] Step 4: based on the pressure increase evaluation value and the pressure maintenance evaluation value of all oil ports, the failure degree of the hydraulically controlled one-way valve to be tested is obtained, and the leakage failure of the hydraulically controlled one-way valve to be tested is evaluated.

[0093] Further, based on the pressure increase evaluation value and the pressure maintenance evaluation value of the oil inlet and the oil outlet of the hydraulically controlled one-way valve to be tested, the leakage fault of the hydraulically controlled one-way valve is evaluated, specifically:

[0094] The pressure-rising evaluation value of the oil inlet, the pressure-rising evaluation value of the oil outlet, the pressure-maintaining evaluation value of the oil inlet and the pressure-maintaining evaluation value of the oil outlet of the hydraulically controlled one-way valve to be tested are used to form a fault evaluation vector;

[0095] By means of a pressure sensor, the pressure-rising section signals and the pressure-maintaining section signals of the oil inlet and the oil outlet of the hydraulically-controlled one-way valve without leakage in the historical period are obtained, and based on the above method, the pressure-rising evaluation value of the oil inlet, the pressure-rising evaluation value of the oil outlet, the pressure-maintaining evaluation value of the oil inlet and the pressure-maintaining evaluation value of the oil outlet of the hydraulically-controlled one-way valve without leakage are calculated to form a historical reference vector;

[0096] Calculating a normalized result of the difference between the fault assessment vector and the historical reference vector, and recording it as a fault degree;

[0097] In this embodiment, the DTW distance between the fault assessment vector and the historical reference vector is calculated, wherein the calculation of the DTW distance is a well-known technology and will not be described in detail here. As other implementation methods, the implementer can adopt other methods of the prior art, such as the inverse of the cosine similarity, etc.; secondly, the sigmoid function is used for normalization processing, wherein the sigmoid function is a well-known technology and will not be described in detail here. As other implementation methods, the implementer can adopt other methods of the prior art, such as the tanh function, etc., and this embodiment does not impose any special restrictions on this.

[0098] If the fault degree is greater than a preset threshold, the hydraulic control one-way valve to be tested has a leakage fault, otherwise, the hydraulic control one-way valve to be tested does not have a leakage fault;

[0099] In this embodiment, the preset threshold value is 0.6. As for other implementation modes, the implementer can set it according to the actual situation.

[0100] It should be noted that the greater the fault degree, the more serious the leakage fault of the hydraulic control one-way valve to be tested is. The step flow chart of the method for obtaining the fault degree provided in the embodiment of the present application is as follows: Figure 3 shown.

[0101] It should be understood that although Figure 1The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. Moreover, Figure 1 At least part of the steps may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least part of the sub-steps or stages of other steps.

[0102] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0103] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the present application. It should be pointed out that, for those of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present application. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present application without departing from the content of the technical solution of the present application, shall fall within the protection scope of the technical solution of the present application.

Claims

1. A method for collecting fault information of a hydraulically controlled one-way valve for a hydraulic support, characterized in that: The method comprises the following steps: The oil inlet and the oil outlet of the hydraulically controlled one-way valve to be tested are recorded as each oil port, and the pressure of each oil port at all times during the pressure-increasing period and the pressure-maintaining period are respectively obtained, which are recorded as the pressure-increasing section signal and the pressure-maintaining section signal of each oil port; Extract the signals with trend items and the signals with trend elimination items from the boost section signals of each oil port; perform modal decomposition on the signals with trend elimination items, analyze the similarity of signals in different time periods in any modal component corresponding to the signals with trend elimination items in the frequency domain, and determine the signal similarity of any modal component; based on the signal similarity, perform signal reconstruction after filtering the modal components, and obtain the boost section signals of each oil port after denoising in combination with the signals with trend items; Based on the change trend of the boost section signal of each oil port after denoising, the boost evaluation value of each oil port is obtained; Perform modal decomposition on the pressure holding section signal of each oil port, analyze the correlation characteristics of each modal component corresponding to the pressure holding section signal of each oil port, screen all modal components and reconstruct the signal to obtain the denoised pressure holding section signal of each oil port; The pressure holding evaluation value of each oil port is determined by the distribution of the pressure holding section signal of each oil port after denoising in the frequency domain; Based on the pressure increase evaluation value and the pressure maintenance evaluation value of all oil ports, the fault degree of the hydraulically controlled one-way valve to be tested is obtained, and the leakage fault of the hydraulically controlled one-way valve to be tested is evaluated.

2. A method for collecting fault information of a hydraulically controlled one-way valve for a hydraulic support as claimed in claim 1, characterized in that: The signal trend elimination method is adopted to extract the signal with trend term and the signal with trend elimination term from the boost section signal of each oil port.

3. A method for collecting fault information of a hydraulically controlled one-way valve for a hydraulic support as claimed in claim 1, characterized in that: The determining the signal similarity of any modal component comprises: Divide any modal component into a plurality of signal segments; perform frequency domain analysis on each signal segment to obtain a frequency spectrum of each signal segment; The signal similarity is the average of the similarities of the frequency spectrograms corresponding to all any two signal segments in any modal component.

4. A method for collecting fault information of a hydraulically controlled one-way valve for a hydraulic support as claimed in claim 1, characterized in that: The process of acquiring the boost section signal after denoising of each oil port is as follows: Obtaining a segmentation threshold of signal similarity of all modal components corresponding to the signal for eliminating the trend term, recorded as a first segmentation threshold; performing signal reconstruction on all modal components of each oil port whose signal similarity is greater than the first segmentation threshold; The amplitude of the reconstructed signal and the signal with trend term at the same time are added to obtain the boost section signal of each oil port after denoising.

5. A method for collecting fault information of a hydraulically controlled one-way valve for a hydraulic support as claimed in claim 1, characterized in that: The boost evaluation value is the slope of the fitted straight line after linear fitting of the boost section signals of each oil port after denoising.

6. A method for collecting fault information of a hydraulically controlled one-way valve for a hydraulic support as claimed in claim 1, characterized in that: A further measurement method of the correlation feature is: calculating the autocorrelation coefficient of each modal component corresponding to the pressure holding section signal of each oil port.

7. A method for collecting fault information of a hydraulically controlled one-way valve for a hydraulic support as claimed in claim 6, characterized in that: The process of obtaining the pressure holding section signal after denoising of each oil port is as follows: Obtaining the segmentation threshold of the autocorrelation coefficients of all modal components corresponding to the pressure-maintaining section signals of each oil port, recorded as the second segmentation threshold; Signal reconstruction is performed on all modal components of each oil port whose autocorrelation coefficient is greater than the second segmentation threshold to obtain a denoised pressure holding section signal of each oil port.

8. A method for collecting fault information of a hydraulically controlled one-way valve for a hydraulic support as claimed in claim 1, characterized in that: Determining the pressure maintenance evaluation value of each oil port includes: The denoised pressure holding signals of each oil port are subjected to frequency domain analysis to obtain a spectrum diagram, and the cumulative sum of the products of all frequency components in the spectrum diagram and their corresponding energies is taken as the pressure holding evaluation value of each oil port.

9. A method for collecting fault information of a hydraulically controlled one-way valve for a hydraulic support as claimed in claim 1, characterized in that: The step of obtaining the fault degree of the hydraulically controlled one-way valve to be tested comprises: The pressure increase evaluation values ​​and pressure maintenance evaluation values ​​of all oil ports of the hydraulically controlled one-way valve to be tested are used to form a fault evaluation vector; Obtain the pressure-rising section signal and the pressure-maintaining section signal of each oil port in the hydraulically-controlled one-way valve without leakage in the historical period, and calculate the pressure-rising evaluation value and the pressure-rising evaluation value of each oil port in the hydraulically-controlled one-way valve without leakage, and form them into a historical reference vector; The difference between the fault assessment vector and the historical reference vector is calculated as the fault degree of the hydraulically controlled one-way valve to be tested.

10. A method for collecting fault information of a hydraulically controlled one-way valve for a hydraulic support as claimed in claim 1, characterized in that: The leakage fault assessment of the hydraulically controlled one-way valve to be tested includes: If the fault degree is greater than a preset threshold, the hydraulically controlled one-way valve to be tested has a leakage fault; otherwise, the hydraulically controlled one-way valve to be tested does not have a leakage fault.

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