阅读说明：本技术 基于阻抗谱的电缆铅封缺陷带电检测系统及其检测方法 (Cable lead sealing defect live-line detection system based on impedance spectrum and detection method thereof ) 是由 杨金海 刘雪锋 李双喜 尹泓江 余磊 林营 王红平 于 2021-10-09 设计创作，主要内容包括：本发明提供一种基于阻抗谱的电缆铅封缺陷带电检测系统及其检测方法,包括便携式计算机检测系统和涡流检测传感器,所述便携式计算机检测系统包括装置外壳,设置在壳体内部的信号发生模块、信号接收模块、信号处理模块、存储模块、电源模块和计算机系统,以及嵌设在壳体上的显示屏和若干按键,所述涡流检测传感器为圆柱形放置探头,包括探头外壳和内部线圈、磁芯,探头与便携式计算机检测系统通过探头连接器和线路连接,便携式计算机检测系统通过处理显示涡流检测传感器探头采集到的探头线圈的阻抗信息,得到阻抗图谱,分析电缆缺陷。本发明检测系统和方法基于对电缆铅封状态下的检测,可及时发现电缆线路的隐患,保证电网安全。(The invention provides an impedance spectrum-based electrified detection system for a cable lead seal defect and a detection method thereof, wherein the electrified detection system comprises a portable computer detection system and an eddy current detection sensor, the portable computer detection system comprises a device shell, a signal generation module, a signal receiving module, a signal processing module, a storage module, a power supply module and a computer system which are arranged in the shell, a display screen and a plurality of keys which are embedded on the shell, the eddy current detection sensor is a cylindrical probe and comprises a probe shell, an internal coil and a magnetic core, the probe is connected with the portable computer detection system through a probe connector and a circuit, and the portable computer detection system obtains an impedance spectrum and analyzes the cable defect by processing and displaying impedance information of the probe coil acquired by the probe of the eddy current detection sensor. The detection system and the detection method are based on detection of the cable in a lead sealing state, can find hidden dangers of a cable line in time, and ensure the safety of a power grid.)

1. The utility model provides a cable lead sealing defect electrified detecting system based on impedance spectroscopy which characterized in that: including portable computer detecting system, eddy current inspection sensor, portable computer detecting system includes the device shell, sets up at inside signal generation module, signal reception module, signal processing module, storage module, power module and the computer system of casing to and inlay display screen and a plurality of button of establishing on the casing, the eddy current inspection sensor is cylindrical places the probe, including probe shell and inner coil, magnetic core, and the probe passes through probe connector and line connection with portable computer detecting system, and portable computer detecting system obtains the impedance map through the impedance information of the probe coil that the processing shows that the eddy current inspection sensor probe was gathered, analysis cable defect.

2. The system for detecting the cable lead sealing defect electrification based on the impedance spectrum as claimed in claim 1, wherein: the probe is an absolute or differential probe and is in a bridge or reflection configuration.

3. The system for detecting the cable lead sealing defect electrification based on the impedance spectrum as claimed in claim 2, wherein: the probe is a point absolute probe, and the probe connector is a 16-pin LEMO or BNC connector.

4. The system for detecting the cable lead sealing defect electrification based on the impedance spectrum as claimed in claim 1, wherein: the frequency range detected by the system is 10Hz-12 MHz.

5. The system for detecting the cable lead sealing defect electrification based on the impedance spectrum as claimed in claim 1, wherein: the system is provided with a high-pass filter and a low-pass filter at the same time, the frequency of the low-pass filter is adjustable within the range of 10Hz-2000Hz, and the frequency of the high-pass filter is adjustable within the range of 5Hz-1000 Hz.

6. The system for detecting the cable lead sealing defect electrification based on the impedance spectrum as claimed in claim 1, wherein: the probe driving comprises three driving voltages, namely low driving voltage, medium driving voltage and high driving voltage, which correspond to 2V, 5V and 8V respectively.

7. The method for detecting the cable lead sealing defect electrified detection system based on the impedance spectrum as claimed in any one of claims 1 to 6, characterized by comprising the following steps:

step 1, connecting an eddy current detection sensor and a portable computer detection system according to equipment requirements;

step 2, starting a portable computer detection system, adjusting a detection mode to be eddy current impedance phase measurement, and setting basic parameters such as a test mode, an absolute measurement path, output signal frequency, a sampling rate, signal driving voltage and the like;

step 3, entering a test operation interface through a key, selecting a proper display parameter, adjusting a display mode, and selecting a display position;

step 4, calibrating the sensor, taking the flat lead sealing surface as a calibration basic surface, and calibrating the detection system;

step 5, performing signal detection, positioning the lead sealing bulge position of the cable joint for the cable joint, holding the probe to be attached to the cable joint positioning position, keeping the probe to be attached to the surface, moving the probe back and forth, clicking a phase angle button in the moving process, rotating a knob to adjust the afterglow to be horizontal, continuously clicking a gain button, and adjusting the appropriate gain until the afterglow is fully paved on a screen;

step 6, positioning defects, namely, carrying out uniform-speed sliding measurement along the lead sealing surface of the cable joint by holding a probe, observing the change of an impedance spectrum on a display screen in real time, adjusting gain and filtering frequency parameters in real time according to the size of a signal, trying to change a measurement track for a typical arc loop area, and finding the position with the maximum signal intensity;

and 7, storing the test result, storing the eddy current map and the parameter table thereof through a storage unit in the system, and recording and storing data and reporting file name information.

Technical Field

The invention belongs to the field of cable detection, and particularly relates to a cable lead sealing defect live-line detection system based on an impedance spectrum and a detection method thereof.

Background

With the continuous development and perfection of the electromagnetic theory and the experiment thereof, the continuous development of nondestructive testing and evaluation technologies such as eddy current testing and the like is promoted. Eddy current technology is widely used because of its many advantages. First, it is a non-contact test and can penetrate the nonconductive cover layer, which makes it unnecessary to perform special surface treatment during the test, thereby shortening the test period and reducing the cost. At the same time, the sensitivity of eddy current detection is very high. Eddy current detection can be classified into single-frequency eddy current, multi-frequency eddy current, pulse eddy current, far-field eddy current, and the like according to the difference between the excitation mode and the detection principle.

The traditional eddy current adopts a single-frequency excitation mode, mainly detects surface and near-surface defects, the excitation frequency ranges from several hertz to several megahertz according to the difference of detected materials and the depth of the defects, in order to obtain a good detection signal, the excitation coil must induce the maximum eddy current near the defects, and the magnitude of the induced current is related to the excitation frequency, the conductivity, the magnetic permeability, the size and the shape of the excitation coil and the magnitude of the excitation current. Detection of defects is achieved by measuring changes in impedance or voltage. However, this affects the detection of defects, since it is also sensitive to other parameters.

In recent years, with the development of scientific technology, the eddy current inspection technology has made breakthrough progress in development and use. From the aspect of hardware technology, the application of large-scale and super-large-scale integrated circuits greatly reduces the volume and power consumption of the instrument; from the aspect of software technology, the performance of a computer microprocessor is greatly improved, the trend of replacing 'soft' with 'hard' is realized, the intelligent level of the whole machine is greatly improved, and the requirement on the operation skill of an instrument user is greatly reduced. At present, the eddy current technology is widely applied to the detection of different materials and structures, mainly comprises the detection of airplane structures, the detection of pressure vessels, the detection of welding structures, and is also used for measuring displacement in addition to the detection of the airplane structures, but the eddy current technology is not basically applied to the defect detection of high-voltage cables. Therefore, modern technology and analysis means are urgently needed to be utilized, technical research is carried out on the specific condition of the lead seal of the cable accessory, the cracking degree of the lead seal can be effectively judged, problems can be found in the early stage of the fault, hidden dangers can be timely eliminated, and loss caused by power faults can be reduced.

Because the domestic application research on the eddy current inspection detection technology is mostly developed in the fields of detection of airplane structures, pressure vessels, welded structures and the like, and the evaluation research on the defect state of the lead seal of a cable accessory is less, the invention aims to provide the cable lead seal defect live-line detection system based on the impedance spectrum and the detection method thereof.

Disclosure of Invention

Aiming at the problems in the prior art, the technical scheme adopted by the invention for solving the problems in the prior art is as follows:

the utility model provides a cable lead sealing defect electrified detecting system based on impedance spectroscopy which characterized in that: including portable computer detecting system, eddy current inspection sensor, portable computer detecting system includes the device shell, sets up at inside signal generation module, signal reception module, signal processing module, storage module, power module and the computer system of casing to and inlay display screen and a plurality of button of establishing on the casing, the eddy current inspection sensor is cylindrical places the probe, including probe shell and inner coil, magnetic core, and the probe passes through probe connector and line connection with portable computer detecting system, and portable computer detecting system obtains the impedance map through the impedance information of the probe coil that the processing shows that the eddy current inspection sensor probe was gathered, analysis cable defect.

The probe is an absolute or differential probe and is in a bridge or reflection configuration.

The probe is a point absolute probe, and the probe connector is a 16-pin LEMO or BNC connector.

The frequency range detected by the system is 10Hz-12 MHz.

The system is provided with a high-pass filter and a low-pass filter at the same time, the frequency of the low-pass filter is adjustable within the range of 10Hz-2000Hz, and the frequency of the high-pass filter is adjustable within the range of 5Hz-1000 Hz.

The probe driving comprises three driving voltages, namely low driving voltage, medium driving voltage and high driving voltage, which correspond to 2V, 5V and 8V respectively.

The detection method of the cable lead sealing defect live detection system based on the impedance spectrum comprises the following steps:

step 1, connecting a probe and a portable computer detection system according to equipment requirements;

step 2, starting a portable computer detection system, adjusting a detection mode to be eddy current impedance phase measurement, and setting basic parameters such as a test mode, an absolute measurement path, output signal frequency, a sampling rate, signal driving voltage and the like;

step 3, entering a test operation interface through a key, selecting a proper display parameter, adjusting a display mode, and selecting a display position; the display mode is divided into three modes of impedance, frequency sweep and frequency sweep + impedance, the impedance mode is generally selected according to the report requirement, and the display position is generally set as the center through the other two auxiliary analyses;

step 4, calibrating the sensor, taking the flat lead sealing surface as a calibration basic surface, calibrating the eddy current flaw detection system, and clicking an automatic lift-off/balance button to place the cursor at the center of the screen;

step 5, performing signal detection, positioning a lead sealing bulge position of the cable joint for the cable joint, holding the probe to be attached to the cable joint positioning position, keeping the probe to be attached to the surface, not needing to be compressed by large force, so as to avoid damaging the cable, moving the probe back and forth, clicking a phase angle button in the moving process for facilitating comparison and observation, rotating a knob to adjust the afterglow to be horizontal, continuously clicking a gain button, dividing the gain button into three types of 'H/V gain', 'horizontal gain' and 'vertical gain', and adjusting proper gain until the afterglow is fully paved on a screen;

step 6, positioning defects, namely, carrying out uniform-speed sliding measurement along the surface of the lead sealing of the cable joint by holding a probe, observing the change of an eddy-current map on a display screen in real time, adjusting parameters such as gain and filtering frequency in real time according to the size of a signal, trying to change a measurement track for a typical arc loop area, and finding the position with the maximum signal intensity;

and 7, storing the test result, storing the eddy current map and the parameter table thereof through a storage unit in the system, and recording and storing data and reporting file name information.

The display mode is divided into three modes of impedance, frequency sweep and frequency sweep + impedance, the impedance mode is generally selected, and the other two auxiliary analyses are carried out, when the current signal injected into the probe coil, the electromagnetic characteristic parameter of the detected conductor and the detection distance are unchanged, the impedance Z of the probe coil becomes a single-value function of the discontinuity of the detected conductor, the discontinuity of the conductor can influence the flow of eddy current, so that the vector point of the eddy current signal in the impedance plane graph moves, and the detection of the discontinuity of the detected body can be realized by detecting the impedance Z of the probe coil. The detection result difference between the trap part and the non-defect part is obvious, the amplitude value of the defect part is larger, and the phase is shifted, so that a typical arc loop is formed; the more serious the lead seal is cracked, the stronger the detection signal intensity is, and the easier the distinguishing is.

The invention has the following advantages:

the detection system and the method can be used for detecting the lead sealing state of various cable accessories, so that the lead sealing state detection is not limited to reference sheath grounding current and contact voltage values any more. The detection process is free from installation and power failure, normal operation of the cable is not affected, the lead sealing state can be mastered before the lead seal is completely cracked, the possibility of line failure is reduced, the efficiency and quality of lead seal detection of the cable accessory can be greatly improved, the cost of manpower and material resources is saved, and safe and stable operation of a power system is ensured.

Based on the monitoring of the lead sealing state of the cable accessory, the method can prevent the cable accessory from getting ill in the bud, timely discover the hidden danger of the cable line, ensure the safety of a power grid, reduce the economic loss caused by the cable fault, has very important significance and positive effect, can reduce large-area power failure caused by accidents, improve the power supply reliability of a power system, and has great economic benefit and social benefit.

Drawings

FIG. 1 is a block diagram of the system architecture of the present invention;

FIG. 2 is an eddy current test map of a lead seal non-defect position on a 110kV high-voltage cable intermediate joint in the embodiment of the invention;

fig. 3 is an eddy current testing map of a lead seal defect on a middle joint of a 110kV high-voltage cable in the embodiment of the invention.

Detailed Description

The technical scheme of the invention is further specifically described by the following embodiments and the accompanying drawings, as shown in fig. 1, the system for detecting the cable lead seal defect electrification based on the impedance spectrum comprises a portable computer detection system and an eddy current detection sensor, wherein the portable computer detection system comprises a device shell, a signal generation module, a signal receiving module, a signal processing module, a storage module, a power supply module and a computer system which are arranged in the shell, and a display screen and a plurality of keys which are embedded on the shell, the eddy current detection sensor is a cylindrical probe, and comprises a probe shell, an internal coil and a magnetic core, and the probe is connected with the portable computer detection system through a probe connector and a line.

The probe is an absolute or differential probe, and a bridge or reflection type configuration is adopted.

The probe is a point absolute probe and the probe connector is a 16 pin LEMO or BNC connector.

The frequency range of system detection is 10Hz-12 MHz.

The system is provided with a high-pass filter and a low-pass filter simultaneously, the frequency of the low-pass filter is adjustable within the range of 10Hz-2000Hz, and the frequency of the high-pass filter is adjustable within the range of 5Hz-1000 Hz.

The probe driving comprises three driving voltages, namely low driving voltage, medium driving voltage and high driving voltage which respectively correspond to 2V, 5V and 8V.

The detection method of the cable lead sealing defect live detection system based on the impedance spectrum comprises the following steps:

step 1, connecting a probe and a portable computer detection system according to equipment requirements;

step 2, starting a portable computer detection system, adjusting a detection mode to be eddy current impedance phase measurement, and setting basic parameters such as a test mode, an absolute measurement path, output signal frequency, a sampling rate, signal driving voltage and the like;

step 3, entering a test operation interface through a key, selecting a proper display parameter, adjusting a display mode, and selecting a display position; the display mode is divided into three modes of impedance, frequency sweep and frequency sweep + impedance, the impedance mode is generally selected according to the report requirement, and the display position is generally set as the center through the other two auxiliary analyses;

step 4, calibrating the sensor, taking the flat lead sealing surface as a calibration basic surface, calibrating the eddy current flaw detection system, and clicking an automatic lift-off/balance button to place the cursor at the center of the screen;

step 5, performing signal detection, positioning a lead sealing bulge position of the cable joint for the cable joint, holding the probe to be attached to the cable joint positioning position, keeping the probe to be attached to the surface, not needing to be compressed by large force, so as to avoid damaging the cable, moving the probe back and forth, clicking a phase angle button in the moving process for facilitating comparison and observation, rotating a knob to adjust the afterglow to be horizontal, continuously clicking a gain button, dividing the gain button into three types of 'H/V gain', 'horizontal gain' and 'vertical gain', and adjusting proper gain until the afterglow is fully paved on a screen;

step 6, positioning defects, namely, carrying out uniform-speed sliding measurement along the surface of the lead sealing of the cable joint by holding a probe, observing the change of an eddy-current map on a display screen in real time, adjusting parameters such as gain and filtering frequency in real time according to the size of a signal, trying to change a measurement track for a typical arc loop area, and finding the position with the maximum signal intensity;

and 7, storing the test result, storing the eddy current map and the parameter table thereof through a storage unit in the system, and recording and storing data and reporting file name information.

As shown in fig. 2 and 3, the eddy current detection maps of the lead seal defect and the non-defect on the middle joint of a certain 110kV high-voltage cable are shown, under the operating environment of the high-voltage cable, the detection signals at the non-defect are basically consistent, the detection signal intensity difference at the defect is small, and the lead seal cracking defect can be distinguished under different operating voltages and load currents.

The system is based on the electromagnetic induction principle, is provided with an independent eddy current detection channel, is externally connected with a special lead seal eddy current detection probe, and realizes the detection of the discontinuity of the surface of the lead seal to be detected, namely the defects of cracks, holes, scratches and the like, by detecting the impedance of a probe coil on the basis that the probe parameters and the lift-off height are kept unchanged. The system can read the impedance value of the eddy current sensor in real time, display and detect the single impedance diagram and the sweep frequency impedance diagram independently or simultaneously, realize the synchronous comparative analysis of the single impedance diagram and the sweep frequency impedance diagram, has the functions of synchronously storing, browsing and exporting data images and setting parameters, and has powerful functions in the aspects of acquisition and setting, signal receiving, signal processing, power management and the like. The system supports the phase angle of the impedance diagram to be adjustable, and the impedance diagram can be rotated by 360 degrees; the position of the support center is adjustable, so that the impedance diagram can be moved at any position in the screen; horizontal gain and vertical gain are supported to be respectively adjusted so as to correspond to a complex test environment on site; the afterglow retaining function is realized, and the retention time can be set and adjusted; the high-pass filter and the low-pass filter are simultaneously arranged, the frequency range of the low-pass filter is adjustable within 10-2000Hz, and the high-pass filter is adjustable within 5-1000Hz and can be set to be closed; the device has two completely independent frequencies, can work simultaneously under the same trigger, and realizes the detection of defects by comparing impedance diagrams under two different frequencies; the device has two completely independent frequencies, can work simultaneously under the same trigger, and realizes the detection of defects by comparing impedance diagrams under two different frequencies; at most, impedance images of three configured parameters can be displayed simultaneously, the impedance images comprise single impedance images and sweep frequency impedance images under different frequencies, and the display positions of the impedance images are customized; two real-time parameters including peak-to-peak value, maximum vertical peak value, maximum horizontal peak value and peak-to-peak angle of each impedance map can be displayed simultaneously; the method can freeze and store the current impedance image of the screen by one key, has the function of signal calibration when the image is frozen, and adjusts the signal gain and phase angle; the system has the functions of one-key data storage and one-key automatic lifting balance, and can realize quick balance and automatic lifting of equipment; the set parameters can be displayed and edited on one page at the same time, and an instrument can be rapidly configured for testing; the operation panel is provided with a shuttle flying knob, so that quick switching and operation can be realized; the data analysis software platform with the PC end can check and analyze test data exported by the host; the signal receiving capability is strong, and a preamplifier is not needed; an instant reference signal can be set to facilitate real-time comparative analysis; the intelligent power management system is arranged, the current electric quantity and the working state can be displayed in real time, the host has three power supply modes, the power supply modes are respectively direct power supply for the charging adapter, the power supply mode of the built-in lithium ion battery and the power supply mode of the built-in AA type alkaline battery box, meanwhile, the type of the built-in battery can be automatically identified, and the adapter is prevented from mistakenly charging the alkaline battery.

The protective scope of the present invention is not limited to the above-described embodiments, and it is apparent that various modifications and variations can be made to the present invention by those skilled in the art without departing from the scope and spirit of the present invention. It is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.