CN222050365U - Cable partial discharge detection device - Google Patents
Cable partial discharge detection device Download PDFInfo
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- CN222050365U CN222050365U CN202420477088.5U CN202420477088U CN222050365U CN 222050365 U CN222050365 U CN 222050365U CN 202420477088 U CN202420477088 U CN 202420477088U CN 222050365 U CN222050365 U CN 222050365U
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- 238000009413 insulation Methods 0.000 abstract description 8
- 238000000034 method Methods 0.000 description 7
- 230000008569 process Effects 0.000 description 7
- 230000005684 electric field Effects 0.000 description 6
- 229910052751 metal Inorganic materials 0.000 description 6
- 239000002184 metal Substances 0.000 description 6
- 230000005540 biological transmission Effects 0.000 description 5
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- 238000005516 engineering process Methods 0.000 description 4
- 239000011810 insulating material Substances 0.000 description 4
- 150000002500 ions Chemical class 0.000 description 4
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- 239000012212 insulator Substances 0.000 description 1
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- 229910052744 lithium Inorganic materials 0.000 description 1
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Abstract
本公开涉及一种电缆线局部放电检测装置，包括用于连接至电缆线终端的高频信号传感器以及固定连接至所述信号传感器的监控主机盒，其中，所述监控主机盒内设有信号调理电路和微处理器模块，所述信号调理电路分别与所述高频信号传感器和所述微处理器模块电连接。这样，采用该电缆线局部放电检测装置，降低了检测人员的劳动强度，提高了局部放电信号检测精度，解除了检测局部放电信号时的人工监管限制，提高了局部放电检测的效率，实现无人值守线缆局部放电自动检测，能够及时发现潜在的绝缘缺陷或故障，避免非计划停电。
The present disclosure relates to a cable line partial discharge detection device, comprising a high-frequency signal sensor for connecting to a cable line terminal and a monitoring host box fixedly connected to the signal sensor, wherein a signal conditioning circuit and a microprocessor module are arranged in the monitoring host box, and the signal conditioning circuit is electrically connected to the high-frequency signal sensor and the microprocessor module respectively. In this way, the use of the cable line partial discharge detection device reduces the labor intensity of detection personnel, improves the detection accuracy of partial discharge signals, removes the manual supervision restrictions when detecting partial discharge signals, improves the efficiency of partial discharge detection, realizes unattended automatic detection of partial discharge of cables, can timely discover potential insulation defects or faults, and avoid unplanned power outages.
Description
Technical Field
The disclosure relates to the technical field of power equipment state detection, in particular to a cable partial discharge detection device.
Background
New energy power generation is a process of generating electric power by using renewable energy sources such as solar energy, wind power and the like, and generally, the generated electric energy needs to be converted into an alternating current for transmission. In the long-time power transmission process of the cable, partial discharge occurs due to aging, damp, mechanical damage, inherent defects of the cable and the like, so that the electric insulation strength is reduced, and after the cable is developed to a certain stage, the cable breaks down or short circuit to cause serious accidents such as power transmission interruption of the new energy power generation station, so that early partial discharge seedlings of the cable are found as early as possible, hidden dangers are treated in time, and the reliable operation of the new energy power generation station is ensured.
In the related technology, when the cable partial discharge is detected, the line is firstly powered off, then the off-line shock wave partial discharge technology is adopted to carry out detection, after the voltage is applied to the detected cable through the shock wave high voltage generating equipment, the partial discharge of the cable insulation defect is excited, a partial discharge signal is captured by a detection sensor in the cable transmission process, the partial discharge signal is processed and analyzed through developed software, and finally, the information of the partial discharge degree, the partial discharge position and the like is judged. The technology needs to carry out partial discharge detection on all cables in the circuit by sections of cables after the cable butt-joint boxes and the box-type transformer parallel connection points are untwisted, and for a new energy station with a longer transmission line, all cable sections can be carried out often in a plurality of weeks, the problem of generating capacity loss caused during power failure is particularly remarkable, and especially the problems of terminal discharge, plug-in elbow-type head dismounting and mounting time and the like when voltage is applied are also considered in the plug-in elbow-type head cable, so that a large amount of personnel labor force is also needed to be input, and the safety of test personnel is threatened.
Meanwhile, as the new energy station is generally installed in a mountain or desert area, the area range is wide, the geography and climate environment are bad, and when the offline shock wave partial discharge detection is carried out, a long signal wire is needed to connect a computer with a partial discharge sensor due to the consideration of the safety distance between a detection person and high-voltage equipment, the unavoidable noise in the environment is introduced, the processing and filtering of the later partial discharge signal are difficult, and the accuracy of signal analysis is difficult.
In addition, the power generated by the new energy station changes along with the changes of factors such as wind speed, wind direction, irradiation intensity and the like, and partial discharge signals can also change along with the changes of the power. The off-line shock wave technology mainly relies on the fact that partial discharge at the cable insulation defect is excited after voltage is manually applied to the cable, firstly, power change, climate change and the like in actual operation conditions cannot be simulated, and the detection mode is single; secondly, the detection of the partial discharge signals in the whole process cannot be realized, and the detection of the partial discharge signals is accidental, so that the detection and tracking of defects are not facilitated.
Disclosure of utility model
It is an object of the present disclosure to provide a cable partial discharge detection apparatus to at least partially solve the problems existing in the related art.
In order to achieve the above-mentioned purpose, the present disclosure provides a cable partial discharge detection device, including be used for being connected to the high frequency signal sensor at cable conductor terminal and fixed connection to the control mainframe box of high frequency signal sensor, wherein, be equipped with signal conditioning circuit and microprocessor module in the control mainframe box, signal conditioning circuit respectively with high frequency signal sensor with microprocessor module electricity is connected.
Optionally, a storage module is further disposed in the monitoring host box, and the storage module is electrically connected with the microprocessor module.
Optionally, a power module is further disposed in the monitoring host box, and the power module is electrically connected with the signal conditioning circuit and the microprocessor module respectively.
Optionally, the high-frequency signal sensor is provided with a round hole for the cable terminal to pass through.
Optionally, the high-frequency signal sensor comprises a first sensor body and a second sensor body, one end of the first sensor body is rotatably connected with one end of the second sensor body, and the other end of the first sensor body is connected with the other end of the second sensor body through a buckle.
Optionally, one end of the first sensor body is rotatably connected with one end of the second sensor body through a hinge.
Optionally, the monitoring main box is welded with the high-frequency signal sensor.
Optionally, the cable termination includes a cable body and a ground wire for connecting the cable body to ground, the high frequency signal sensor being connected to the ground wire.
Optionally, the outer end of the cable body is sleeved with a metal shielding layer.
Optionally, the microprocessor module is a single-chip microcomputer.
Through the technical scheme, the cable partial discharge detection device is formed by the high-frequency signal sensor and the monitoring mainframe box into a whole, the monitoring mainframe box is directly connected with the sensor, overlong signal line connection is reduced, noise during detection is reduced, and labor intensity of detection by detection personnel is also reduced. The high-frequency signal sensor is connected to the cable terminal, and when partial discharge occurs in the cable, the high-frequency signal sensor transmits detected signals to the signal conditioning circuit, and after the signal conditioning circuit processes the signals, the signals are transmitted to the microprocessor module for analysis and processing. By adopting the cable partial discharge detection device, the labor intensity of detection personnel is reduced, the detection precision of partial discharge signals is improved, the manual supervision limit during detection of the partial discharge signals is relieved, the efficiency of partial discharge detection is improved, the automatic detection of the partial discharge of the unattended cable is realized, the potential insulation defect or fault can be found in time, and the unplanned power failure is avoided.
Additional features and advantages of the present disclosure will be set forth in the detailed description which follows.
Drawings
The accompanying drawings are included to provide a further understanding of the disclosure, and are incorporated in and constitute a part of this specification, illustrate the disclosure and together with the description serve to explain, but do not limit the disclosure. In the drawings:
fig. 1 is a schematic structural view of a cable partial discharge detection device according to an exemplary embodiment of the present disclosure;
FIG. 2 is a diagram showing an electrical connection relationship between a high-frequency signal sensor and a monitoring host box in a cable partial discharge detection device according to an exemplary embodiment of the present disclosure;
FIG. 3 is a schematic diagram of a connection between a cable partial discharge detection device and a cable termination according to an exemplary embodiment of the present disclosure;
fig. 4 is an assembly diagram of a cable body and a metal shielding layer in a partial discharge detection apparatus for a cable according to an exemplary embodiment of the present disclosure.
Description of the reference numerals
1 High frequency signal sensor 11 first sensor body
12 Second sensor body 13 fastener
14 Hinge 2 monitoring host box
21 Signal conditioning circuit 22 microprocessor module
23 Memory module 24 power supply module
31 Cable body 32 grounding wire
4 Metal shielding layer 5 wire core
Detailed Description
Specific embodiments of the present disclosure are described in detail below with reference to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating and illustrating the disclosure, are not intended to limit the disclosure.
In the present disclosure, unless otherwise stated, "inner", "outer" are with respect to the own outline of the corresponding parts, and furthermore, the terms "first", "second", etc. are used in the present disclosure to distinguish one element from another, without having order or importance. In the present disclosure, when the following description refers to the accompanying drawings, the same numbers in different drawings refer to the same or similar elements unless otherwise indicated.
Referring to fig. 1 to 4, the present disclosure provides a cable partial discharge detection apparatus, which may include a high frequency signal sensor 1 for connection to a cable terminal and a monitoring main box 2 fixedly connected to the high frequency signal sensor 1, wherein a signal conditioning circuit 21 and a microprocessor module 22 are provided in the monitoring main box 2, and the signal conditioning circuit 21 is electrically connected to the high frequency signal sensor 1 and the microprocessor module 22, respectively. It should be noted that the partial discharge refers to a partial discharge phenomenon occurring inside or on the surface of the insulator, which is an electrical phenomenon that causes gradual damage to insulation and may eventually cause malfunction of the apparatus. Partial discharge is typically caused by arcing, gas breakdown, air ionization, and the like.
When the cable insulating material of the new energy station has defects such as bubbles, foreign matters, sharp conductors and the like, the defects can lead to electric field concentration, so that the local electric field intensity is increased, and when the electric field intensity exceeds the breakdown electric field intensity of the insulating material, the electric breakdown phenomenon at the local defect can occur; when the local electric field strength exceeds the breakdown electric field strength, electrons at the local defects are accelerated, collide with the insulating material and release energy, high-energy electrons, ions and electron holes are generated in the process, and the released high-energy electrons and ions move in the insulating material and collide with other atoms or molecules, and more electrons and ions are excited due to the collision. During partial discharge, electromagnetic radiation is generated that oscillates at high frequencies due to collisions of electrons and ions and their interactions with other particles in the material. Accordingly, the high-frequency signal sensor 1 may be installed on the outer wall of the cable terminal of the new energy station to measure the partial discharge signal. The high-frequency signal sensor 1 is used for detecting a high-frequency signal generated by partial discharge of a cable, the inside of the monitoring host box 2 is a circuit board integrated with the signal conditioning circuit 21 and the microprocessor module 22, and an output signal of the high-frequency signal sensor 1 is input to the signal conditioning circuit 21, so that the high-frequency signal sensor 1 and the monitoring host box 2 form a whole.
Through the technical scheme, the cable partial discharge detection device is formed by the high-frequency signal sensor and the monitoring mainframe box into a whole, the monitoring mainframe box is directly connected with the sensor, overlong signal line connection is reduced, noise during detection is reduced, and labor intensity of detection by detection personnel is also reduced. The high-frequency signal sensor is connected to the cable terminal, and when partial discharge occurs in the cable, the high-frequency signal sensor transmits detected signals to the signal conditioning circuit, and after the signal conditioning circuit processes the signals, the signals are transmitted to the microprocessor module for analysis and processing. By adopting the cable partial discharge detection device, the labor intensity of detection personnel is reduced, the detection precision of partial discharge signals is improved, the manual supervision limit during detection of the partial discharge signals is relieved, the efficiency of partial discharge detection is improved, the automatic detection of the partial discharge of the unattended cable is realized, the potential insulation defect or fault can be found in time, and the unplanned power failure is avoided.
Further, referring to fig. 2, a storage module 23 may be further disposed in the monitoring host box 2, and the storage module 23 is electrically connected to the microprocessor module 22. The microprocessor module 22 controls the signal conditioning circuit 21 to collect partial discharge signals of the tested cable, and processes the signals sent by the signal conditioning circuit 21 to improve data quality and determine the partial discharge state of the tested cable, and then the partial discharge state is transferred into the storage module 23 for storage, so that the workers can detect the partial discharge state at any time. By introducing the storage module 23 and optimizing the structure of the traditional detection device, the length of the signal connecting wire is reduced, so that the partial discharge detection is not limited by external conditions, and the detection of the partial discharge signal of the cable line of the new energy station in an online and whole process is realized. Specifically, the storage module 23 may be an SD card.
Further, referring to fig. 2, a power module 24 may be further disposed in the monitoring host box 2, where the power module 24 is electrically connected to the signal conditioning circuit 21 and the microprocessor module 22, respectively, so as to perform a function of supplying power to the signal conditioning circuit 21 and the microprocessor module 22. In particular, the power module 24 may be a removable, rechargeable lithium battery.
When the detection device works, firstly, partial discharge high-frequency signals of a cable terminal of a new energy station are collected through a high-frequency signal sensor 1, then, the signals are subjected to signal processing through a signal conditioning circuit 21, then, a microprocessor module 22 carries out pretreatment on the signals processed by the signal conditioning circuit 21 so as to improve data quality and determine the partial discharge state of a cable to be detected, and then, the processed partial discharge high-frequency signals are sent into a storage module 23, wherein a power module 24 continuously supplies power for the signal conditioning circuit 21 and the microprocessor module 22, and a detection personnel needs to take out the power module 24 for charging at intervals and replace the power module 24 with another identical power module 24; when the partial discharge high-frequency signal is required to be detected, a worker can know whether the cable has the partial discharge phenomenon or not only by taking the storage module 23 in the device out and putting the storage module into a computer for reading, so that the detector can timely detect the partial discharge phenomenon of the cable.
In some embodiments, referring to fig. 1, the high frequency signal sensor 1 may be provided with a circular hole for the passage of a power supply cable terminal. The round hole can be more attached to the cable terminal, so that partial discharge high-frequency signals of the cable terminal can be collected more conveniently. The high-frequency signal sensor 1 is sleeved on the cable wire through a round hole, and when the cable is subjected to partial discharge, the high-frequency signal sensor 1 can transmit detected signals to the signal conditioning circuit 21.
According to some embodiments, referring to fig. 1, the high frequency signal sensor 1 may include a first sensor body 11 and a second sensor body 12, one end of the first sensor body 11 is rotatably connected with one end of the second sensor body 12, and the other end of the first sensor body 11 is connected with the other end of the second sensor body 12 through a buckle 13. When the cable partial discharge detection device is installed, the buckle 13 is firstly opened, then the cable is sleeved with the round hole formed in the middle, and then the buckle 13 is buckled, so that the detection device is fixed on the cable.
Further, referring to fig. 1, one end of the first sensor body 11 and one end of the second sensor body 12 may be rotatably connected by a hinge 14. The rotatable connection manner of the first sensor body 11 and the second sensor body 12 is not limited in the present disclosure, and all fall within the protection scope of the present disclosure.
Specifically, the monitoring main box 2 can be welded with the high-frequency signal sensor 1 so as to form a whole, and overlong signal wire connection is reduced. In other embodiments, the monitoring main box 2 and the high-frequency signal sensor 1 may be connected by a connection manner such as a bolt connection or a clamping connection.
As an exemplary embodiment of the present disclosure, referring to fig. 3, the cable wire terminal may include a cable wire body 31 and a ground wire 32 for connecting the cable wire body 31 to the ground, and the high frequency signal sensor 1 is connected to the ground wire 32. When the cable body 31 discharges, the high-frequency pulse current flows to the grounding wire 32, and the high-frequency signal sensor 1 is sleeved on the grounding wire 32 more conveniently.
According to an exemplary embodiment of the present disclosure, referring to fig. 4, the outer end of the cable body 31 may be sheathed with a metal shielding layer 4. The cable body 31 may include a core 5 and an insulating layer sleeved on the core 5. In high-voltage cables, the insulation layer separates the core 5 from the metallic shielding layer 4 to form a distributed capacitance, which is about several hundred pF, forming a path for high-frequency signals. Thus, the partial discharge signal of high frequency is transmitted in a loop by the distributed capacitance to the ground line 32. When internal discharge occurs, a high-frequency pulse current is generated, and the high-frequency pulse current flows from the high-potential wire core 5 to the low-potential metal shielding layer 4 through the distributed capacitance between the wire core 5 and the metal shielding layer 4, and enters the ground through the ground wire 32. Thus, by connecting a partial discharge detection device to the ground line 32, a high frequency pulsed partial discharge current can be coupled into the device to detect the partial discharge signal.
The microprocessor module 22 may be a single-chip microcomputer. The present disclosure is not limited in the structure of microprocessor module 22.
The preferred embodiments of the present disclosure have been described in detail above with reference to the accompanying drawings, but the present disclosure is not limited to the specific details of the embodiments described above, and various simple modifications may be made to the technical solutions of the present disclosure within the scope of the technical concept of the present disclosure, and all the simple modifications belong to the protection scope of the present disclosure.
In addition, the specific features described in the foregoing embodiments may be combined in any suitable manner, and in order to avoid unnecessary repetition, the present disclosure does not further describe various possible combinations.
Moreover, any combination between the various embodiments of the present disclosure is possible as long as it does not depart from the spirit of the present disclosure, which should also be construed as the disclosure of the present disclosure.
Claims (10)
1. The cable partial discharge detection device is characterized by comprising a high-frequency signal sensor and a monitoring host box, wherein the high-frequency signal sensor is connected to a cable terminal, the monitoring host box is fixedly connected to the high-frequency signal sensor, a signal conditioning circuit and a microprocessor module are arranged in the monitoring host box, and the signal conditioning circuit is respectively and electrically connected with the high-frequency signal sensor and the microprocessor module.
2. The cable partial discharge detection device according to claim 1, wherein a storage module is further provided in the monitoring main box, and the storage module is electrically connected with the microprocessor module.
3. The cable partial discharge detection device according to claim 1, wherein a power module is further disposed in the monitoring main box, and the power module is electrically connected with the signal conditioning circuit and the microprocessor module respectively.
4. The apparatus according to claim 1, wherein the high-frequency signal sensor is provided with a circular hole for the cable terminal to pass through.
5. The cable partial discharge detection device according to claim 4, wherein the high-frequency signal sensor includes a first sensor body and a second sensor body, one end of the first sensor body is rotatably connected with one end of the second sensor body, and the other end of the first sensor body is connected with the other end of the second sensor body through a buckle.
6. The partial discharge detector for electric cable according to claim 5, wherein one end of the first sensor body is rotatably connected to one end of the second sensor body by a hinge.
7. The apparatus of claim 1, wherein the monitoring main box is welded to the high frequency signal sensor.
8. The cable partial discharge detection apparatus according to claim 1, wherein the cable terminal includes a cable body and a ground line for connecting the cable body to the ground, the high-frequency signal sensor being connected to the ground line.
9. The apparatus of claim 8, wherein the outer end of the cable body is jacketed with a metallic shield.
10. The apparatus of claim 1, wherein the microprocessor module is a single-chip microcomputer.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202420477088.5U CN222050365U (en) | 2024-03-12 | 2024-03-12 | Cable partial discharge detection device |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202420477088.5U CN222050365U (en) | 2024-03-12 | 2024-03-12 | Cable partial discharge detection device |
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| CN222050365U true CN222050365U (en) | 2024-11-22 |
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| CN202420477088.5U Active CN222050365U (en) | 2024-03-12 | 2024-03-12 | Cable partial discharge detection device |
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