Method for identifying external breaking events of different types of cable breaking hammers

Abstract

The invention relates to a method for identifying external breaking events of different types of cable breaking hammers, and belongs to the technical field of monitoring by using measured values of data signals. The method comprises the following steps: collecting historical vibration acceleration data of each type of historical breaking hammer external breaking event; performing low-pass filtering on the vibration data; performing standardization processing on the vibration data after low-pass filtering; constructing an upper envelope line of the vibration data; extracting a peak value and a time interval of the upper envelope line; calculating an average value and a standard deviation of the peak time interval to obtain a historical vibration characteristic value; similarly, for the to-be-recognized breaking hammer external breaking event, obtaining a to-be-recognized vibration characteristic value; and according to the average distance between the vibration characteristic value to be identified and the vibration characteristic value of the different types of historical breaking hammer external damage events, identifying which type of cable breaking hammer external damage events belongs to. The method is simple, event types can be identified, the accuracy is high, and the cable is prevented from being damaged by construction.

Description

Technical Field

[0001] The present invention relates to a method for identifying different types of cable breaker external breakage events, belonging to the technical field of measurement value monitoring using data signals (H04B10 / 079). Background Art

[0002] With the continuous development of social economy, the scale of urban power grid construction is expanding day by day, and a large number of underground cable lines have been built and put into use, providing important power support for economic development. However, there are a lot of construction activities in cities every day, among which illegal construction, barbaric construction and improper operation threaten the safe operation of transmission cables at any time. Construction machinery, especially hammers, can easily dig or break cables in the process of destroying the road surface, causing power outages and even personal injury accidents, which has a serious negative impact on society.

[0003] Different types of breakers have different working principles and operating methods, so they bring different risks and impacts. For example, hydraulic breakers use powerful impact force to break the ground, and are usually used to deal with hard concrete and rocks. If they are not operated properly, they can easily cause serious damage to underground cables in a short period of time. This type of equipment has a large impact force and damages a wide range of cables, which may cause large-scale power outages and be difficult to repair. Pneumatic breakers are driven by compressed air. Although the impact force is small and suitable for small and medium-sized construction, their continuous vibration also poses a risk of damage to shallow cables, especially under dense urban roads. If the operator is not vigilant, it may still cause local cable damage.

[0004] At present, the main methods for identifying cable breaker external failure events near roads include manual inspection and monitoring device identification. Manual inspection is time-consuming and labor-intensive, with low efficiency and difficulty in covering large cable lines. The monitoring device identification method mainly determines whether an external failure event has occurred by vibration amplitude. However, due to the different vibration intensities and patterns caused by different types of breakers, existing monitoring devices are prone to mistaking vibrations caused by non-breakers such as road vehicles for external failure events, resulting in a high misjudgment rate and an inability to accurately identify the type of cable breaker external failure event.

[0005] Therefore, there is an urgent need for a method that can identify different types of cable breaker hammer external failure events so that targeted preventive measures can be taken in advance to effectively protect cables and ensure power supply, which is of great practical significance for maintaining urban safety and economic stability. Summary of the invention

[0006] The technical problem to be solved by the present invention is: how to identify different types of cable breaker external failure events.

[0007] The technical solution proposed by the present invention to solve the above technical problems is: a method for identifying different types of cable breaker external failure events, comprising the following steps:

[0008] Step 1: Collect historical cable breaker hammer external failure events, and classify the historical cable breaker hammer external failure events into different types according to the type of breaker hammer;

[0009] Collect each historical vibration acceleration data around the cable in each type of historical cable breaker external breakage event;

[0010] Step 2: Low-pass filter all historical vibration acceleration data;

[0011] Step 3: Standardize all historical vibration acceleration data after low-pass filtering according to formula (1)

[0012] a s (i)= a(i) / max(|a(i)|) (1);

[0013] In formula (1), a(i) is the amplitude of the i-th vibration point in the historical vibration acceleration data; a s (i) is the normalized amplitude of the i-th vibration point in the historical vibration acceleration data;

[0014] Step 4: construct the upper envelope of each history for each standardized historical vibration acceleration data;

[0015] Step 5: Setting the set vibration time interval and vibration amplitude of the upper envelope of the history;

[0016] Step 5.1: The point in the upper envelope of each history where the vibration time interval is greater than the set vibration time interval and the vibration amplitude is greater than the set vibration amplitude is taken as the peak point of the upper envelope of each history;

[0017] Step 5.2: Calculate the average value t and standard deviation d of the time intervals between adjacent peak points in each historical upper envelope; use the average value t and standard deviation d in each historical upper envelope as the historical vibration characteristic value;

[0018] Step 6: Collect vibration acceleration data around the cable to be identified in the cable breaker external break event to be identified;

[0019] Step 6.1: low-pass filtering the vibration acceleration data to be identified;

[0020] Step 6.2: standardize the vibration acceleration data to be identified after low-pass filtering according to formula (1);

[0021] Step 6.3: construct an upper envelope to be identified for the vibration acceleration data to be identified after the standardized processing;

[0022] Step 6.4: taking the point in the upper envelope to be identified where the vibration time interval is greater than the set vibration time interval and the vibration amplitude is greater than the set vibration amplitude as the peak point of the upper envelope to be identified;

[0023] Step 6.5: Calculate the average value of the time intervals between adjacent peak points in the upper envelope to be identified and standard deviation , and the average value and standard deviation As the vibration characteristic value to be identified;

[0024] Step 6.6: Calculate the average distance D between the vibration feature to be identified and the historical vibration feature value according to the following formula (2): j

[0025] (2);

[0026] In formula (2), N j is the number of historical vibration eigenvalues ​​of the j-th type of historical cable breaker external failure events;

[0027] t j,n is the average value of the time intervals between adjacent peaks in the nth historical vibration characteristic value of the jth type of historical breaker external breaking event;

[0028] d j,n is the standard deviation of the time intervals between adjacent peaks in the nth historical vibration characteristic value of the jth type of historical breaker external failure event;

[0029] Step 6.7: If When the historical vibration characteristic value of the historical breaker external failure event corresponding to the minimum value contains the vibration characteristic value to be identified, the breaker external failure event to be identified is determined to be the The historical breaker external failure events corresponding to the minimum time;

[0030] like When the historical vibration characteristic value of the historical breaker external failure event corresponding to the minimum does not include the vibration characteristic value to be identified, the breaker external failure event to be identified is determined as not being any type of historical breaker external failure event.

[0031] Furthermore, in step 1, historical vibration acceleration data is collected within a range of 10 m around the cable with a collection time of 5 s and a sampling rate of 48 kHz.

[0032] Furthermore, in step 4, the vibration maximum value is calculated for every 960 points of the standardized vibration acceleration data, and all vibration maximum values ​​are interpolated three times by spline interpolation to obtain the historical upper envelope of the standardized historical vibration acceleration data.

[0033] The beneficial effects of the present invention are as follows: by collecting historical vibration acceleration data of cables in various types of historical breaker hammer external breakage events to obtain the average value and standard deviation of the peak time intervals in the historical envelope, the vibration characteristic value is calculated, and the cable breaker hammer external breakage event is automatically identified according to the average distance between the vibration characteristic value to be identified and the historical vibration characteristic values ​​of various types of historical breaker hammer external breakage events, without the need for manual patrol and identification, thus saving time and effort and having higher identification efficiency. At the same time, the shortcomings of high misjudgment rate and inability to identify the type of external breakage event when only using vibration amplitude to identify cable external breakage events are overcome, and the identification method of the present invention is simple and has higher accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The method for identifying different types of cable breaker external failure events of the present invention will be further described below in conjunction with the accompanying drawings.

[0035] Figure 1 It is a time domain waveform diagram of historical vibration acceleration data in the method for identifying different types of cable breaker external failure events in Example 1.

[0036] Figure 2 It is a spectrum diagram of historical vibration acceleration data in the method for identifying different types of cable breaker external failure events in Example 1.

[0037] Figure 3 1 is an upper envelope diagram of the history of the method for identifying different types of cable breaker external failure events in Example 1.

[0038] Figure 4 It is a peak point diagram of the historical envelope in the method for identifying different types of cable breaker external failure events in Example 1.

[0039] Figure 5 It is a schematic diagram of the determination of the method for identifying different types of cable breaker external failure events in Example 1.

[0040] Figure 6 It is a peak point diagram of the upper envelope to be identified in the method for identifying different types of cable breaker external failure events in Example 2. DETAILED DESCRIPTION

[0041] Example 1

[0042] A method for identifying different types of cable breaker external failure events in this embodiment includes the following steps:

[0043] Step 1: Collect historical cable breaker hammer external failure events, and classify the historical cable breaker hammer external failure events into different types according to the type of breaker hammer;

[0044] This embodiment divides historical cable breaker external failure events into three types;

[0045] Collect each historical vibration acceleration data around the cable in each type of historical cable breaker external breakage event;

[0046] In this embodiment, historical vibration acceleration data is collected within a range of 10m around the cable with a collection time of 5s and a sampling rate of 48kHz. The time domain waveform of one of the collected historical vibration acceleration data is shown in the figure below: Figure 1 As shown, the spectrum diagram is Figure 2 shown.

[0047] Step 2: Low-pass filter all historical vibration acceleration data;

[0048] like Figure 2 As shown, since the spectrum of the historical vibration acceleration data is mainly concentrated in the range of 3kHz, a 10th-order Butterworth low-pass filter with a cutoff frequency of 3kHz is used to low-pass filter the historical vibration acceleration data to reduce the influence of other external vibrations.

[0049] Step 3: Standardize all historical vibration acceleration data after low-pass filtering according to formula (1)

[0050] a s (i)= a(i) / max(|a(i)|) (1);

[0051] In formula (1), a(i) is the amplitude of the i-th vibration point in the historical vibration acceleration data, a s (i) is the normalized amplitude of the i-th vibration point in the historical vibration acceleration data;

[0052] The vibration amplitudes of different types of historical breaker external failure events vary greatly and are related to the distance from the external failure location. Figure 2 The time domain waveform of historical vibration acceleration data is standardized.

[0053] Step 4: construct the upper envelope of each history for each standardized historical vibration acceleration data;

[0054] After standardization, the time domain waveform is still not smooth, and it is difficult to directly extract vibration features. Therefore, the maximum vibration value is calculated every 960 points for the standardized historical vibration acceleration data a, and all vibration maximum values ​​are interpolated three times to obtain the upper envelope a of the standardized historical vibration acceleration data. u ,like Figure 3 shown.

[0055] Step 5: Set the vibration time interval of the upper envelope of the history to 0.1s and the vibration amplitude to 0.6;

[0056] Step 5.1: The point in the upper envelope of each history where the vibration time interval is greater than the set vibration time interval and the vibration amplitude is greater than the set vibration amplitude is taken as the peak point of the upper envelope of each history;

[0057] To further highlight the historical envelope a u The changing law of vibration in Figure 3 The point where the vibration time interval exceeds 0.1s and the vibration amplitude exceeds 0.6 is taken as the peak point of the historical envelope, such as Figure 4 As shown, there are 24 peak points of the envelope in history;

[0058] Step 5.2: Calculate the average value t and standard deviation d of the time intervals between adjacent peak points in each historical upper envelope; use the average value t and standard deviation d in each historical upper envelope as the historical vibration characteristic value;

[0059] This step is to avoid Figure 4 Interference of a peak point with a lower amplitude; one of the historical vibration characteristic values ​​calculated in this embodiment is (t=0.2083, d=0.0153).

[0060] Step 6: Collect vibration acceleration data around the cable to be identified in the cable breaker external break event to be identified;

[0061] Step 6.1: low-pass filter the vibration acceleration data to be identified;

[0062] Step 6.2: Standardize the vibration acceleration data to be identified according to formula (1);

[0063] Step 6.3: construct an upper envelope to be identified for the vibration acceleration data to be identified after the standardized processing;

[0064] Step 6.4: taking the point in the upper envelope to be identified where the vibration time interval is greater than the set vibration time interval and the vibration amplitude is greater than the set vibration amplitude as the peak point of the upper envelope to be identified;

[0065] Step 6.5: Calculate the average of the time intervals between adjacent peaks in the upper envelope to be identified and standard deviation , and the average value and standard deviation As the vibration characteristic value to be identified;

[0066] The vibration characteristic value to be identified obtained in this embodiment is ( =0.2178, =0.0593);

[0067] Step 6.6: Calculate the average distance D between the vibration feature to be identified and all historical vibration feature values ​​in various types of historical cable breaker external failure events according to formula (2). j

[0068] (2);

[0069] In formula (2), N j is the number of historical vibration eigenvalues ​​of the j-th type of historical cable breaker external failure events;

[0070] t j,n is the average time interval between adjacent peaks in the nth historical vibration characteristic value of the jth type of historical breaker external failure event;

[0071] d j,n is the standard deviation of the time intervals between adjacent peaks in the nth historical vibration characteristic value of the jth type of historical breaker external failure event;

[0072] In this embodiment, according to formula (2), D1=0.05, D2=0.13, D3=0.24 are calculated;

[0073] Step 6.7: If When the historical vibration characteristic value of the historical breaker external failure event corresponding to the minimum value contains the vibration characteristic value to be identified, the breaker external failure event to be identified is determined to be The historical breaker external failure events corresponding to the minimum time;

[0074] like When the historical vibration characteristic value of the historical breaker external break event corresponding to the minimum does not include the vibration characteristic value to be identified, the breaker external break event to be identified is determined as not being any type of historical breaker external break event;

[0075] like Figure 5 As shown, D1 is the smallest, and the historical vibration characteristic value of the first type of historical breaker external failure event includes the vibration characteristic value to be identified, so the breaker external failure event to be identified is determined to be the first type of historical breaker external failure event.

[0076] Example 2

[0077] The method for identifying different types of cable breaker external failure events in this embodiment is basically the same as that in embodiment 1. The difference is that the peak point diagram of the upper envelope to be identified is as follows: Figure 6 As shown, the vibration characteristic value to be identified obtained in step 6.5 of this implementation is ( =1.0816, =1.5363), step 6.6 In this embodiment, D1=0.16, D2=0.09, and D3=0.22 are calculated according to formula (2).

[0078] Step 6.7: If When the historical vibration characteristic value of the historical breaker external failure event corresponding to the minimum value contains the vibration characteristic value to be identified, the breaker external failure event to be identified is determined to be The historical breaker external failure events corresponding to the minimum time;

[0079] like When the historical vibration characteristic value of the historical breaker external failure event corresponding to the minimum does not include the vibration characteristic value to be identified, the breaker external failure event to be identified is determined as not being any type of historical breaker external failure event.

[0080] In this embodiment, D2 is the smallest, but the vibration characteristic value of the second type of historical breaker hammer external failure event does not include the vibration characteristic value to be identified, so the breaker hammer external failure event to be identified is not one of the three types of historical cable breaker hammer external failure events.

[0081] The above description is only a preferred embodiment of the present invention, but the present invention is not limited thereto. All equivalent replacements or equivalent changes of the concepts and technical solutions according to the present invention should be included in the protection scope of the present invention.

Claims

1. A method for identifying different types of cable breaker external failure events, characterized in that The following steps are involved: Step 1: Collect historical cable breaker hammer external failure events, and classify the historical cable breaker hammer external failure events into different types according to the type of breaker hammer; Collect each historical vibration acceleration data around the cable in each type of historical cable breaker external breakage event; Step 2: Low-pass filter all historical vibration acceleration data; Step 3: Standardize all historical vibration acceleration data after low-pass filtering according to formula (1) a s (i)= a(i) / max(|a(i)|) (1); In formula (1), a(i) is the amplitude of the i-th vibration point in the historical vibration acceleration data; a s (i) is the normalized amplitude of the i-th vibration point in the historical vibration acceleration data; Step 4: construct the upper envelope of each history for each standardized historical vibration acceleration data; Step 5: Setting the set vibration time interval and vibration amplitude of the upper envelope of the history; Step 5.1: The point in the upper envelope of each history where the vibration time interval is greater than the set vibration time interval and the vibration amplitude is greater than the set vibration amplitude is taken as the peak point of the upper envelope of each history; Step 5.2: Calculate the average value t and standard deviation d of the time intervals between adjacent peak points in each historical upper envelope; use the average value t and standard deviation d in each historical upper envelope as the historical vibration characteristic value; Step 6: Collect vibration acceleration data around the cable to be identified in the cable breaker external break event to be identified; Step 6.1: low-pass filtering the vibration acceleration data to be identified; Step 6.2: standardize the vibration acceleration data to be identified after low-pass filtering according to formula (1); Step 6.3: construct an upper envelope to be identified for the vibration acceleration data to be identified after the standardized processing; Step 6.4: taking the point in the upper envelope to be identified where the vibration time interval is greater than the set vibration time interval and the vibration amplitude is greater than the set vibration amplitude as the peak point of the upper envelope to be identified; Step 6.5: Calculate the average value of the time intervals between adjacent peak points in the upper envelope to be identified and standard deviation , and the average value and standard deviation As the vibration characteristic value to be identified; Step 6.6: Calculate the average distance D between the vibration feature to be identified and the historical vibration feature value according to the following formula (2): j （2）； In formula (2), N j is the number of historical vibration eigenvalues ​​of the j-th type of historical cable breaker external failure events; t j,n is the average value of the time intervals between adjacent peaks in the nth historical vibration characteristic value of the jth type of historical breaker external breaking event; d j,n is the standard deviation of the time intervals between adjacent peaks in the nth historical vibration characteristic value of the jth type of historical breaker external failure event; Step 6.7: If When the historical vibration characteristic value of the historical breaker external failure event corresponding to the minimum value contains the vibration characteristic value to be identified, the breaker external failure event to be identified is determined to be the The historical breaker external failure events corresponding to the minimum time; like When the historical vibration characteristic value of the historical breaker external failure event corresponding to the minimum does not include the vibration characteristic value to be identified, the breaker external failure event to be identified is determined as not being any type of historical breaker external failure event.

2. The method for identifying different types of cable breaker external failure events according to claim 1, characterized in that: The step 1 is to collect historical vibration acceleration data within a range of 10m around the cable with a collection time of 5s and a sampling rate of 48kHz.

3. The method for identifying different types of cable breaker external failure events according to claim 1, characterized in that: In step 4, the maximum vibration value is calculated every 960 points of the standardized historical vibration acceleration data, and all the vibration maximum values ​​are interpolated three times to obtain the historical upper envelope of the standardized historical vibration acceleration data.

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