CN217443474U - Cable fault detection device - Google Patents
Cable fault detection device Download PDFInfo
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- CN217443474U CN217443474U CN202123361246.6U CN202123361246U CN217443474U CN 217443474 U CN217443474 U CN 217443474U CN 202123361246 U CN202123361246 U CN 202123361246U CN 217443474 U CN217443474 U CN 217443474U
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- cable
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- supporting member
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y04—INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
- Y04S—SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
- Y04S10/00—Systems supporting electrical power generation, transmission or distribution
- Y04S10/50—Systems or methods supporting the power network operation or management, involving a certain degree of interaction with the load-side end user applications
- Y04S10/52—Outage or fault management, e.g. fault detection or location
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Abstract
The utility model relates to a detection apparatus for cable fault, include: one end of the first coil is electrically connected with the signal acquisition unit, and the other end of the first coil is arranged on the outer layer of the cable body in a winding manner; the one end of second coil with the other end electric connection of first coil, the other end winding of second coil sets up in the skin of ground connection cable, warp outer, with signal acquisition unit electric connection, the ground connection cable is the sheath ground connection part of cable body when the terminal separation. By adopting the device, the sheath current in the cable body monitored by the coil and the current generated by the grounding cable can be mutually offset to obtain the transmission current of the cable core, so that whether the cable breaks down or not can be safely and accurately judged according to the size of the transmission current with lower cost.
Description
Technical Field
The utility model relates to the technical field of cables, especially, relate to a detection device of cable fault.
Background
Along with the promotion of high tension cable rate of utilization and total amount, the fortune dimension volume of cable also increases correspondingly, urgently needs effectual detection means to carry out early warning and location to the hidden danger and the trouble of cable. In the related art, the cable body is passed through the coil sensor, and then the sheath grounding wire of the cable is passed through the coil sensor in the opposite direction, so that the sheath current on the body and the sheath current on the grounding wire are fed into and discharged from the coil sensor at the same time, and the sheath current are offset with each other. The inner diameter of the coil sensor is relatively large due to the simultaneous penetration of the body and the sheath, for example, in order to adapt to most of the outer diameter of the 220kV cable, the inner diameter of the sensor is required to be about 240 mm. Therefore, the size of the sensor is large, and the manufacturing cost is high.
In other related technologies, when a cable terminal separates a cable core and a sheath grounding wire of a cable, a coil sensor is mounted on the cable core, and the mounting space for the cable core to be connected with the cable is limited, so that the coil sensor is too close to an insulated terminal of the cable terminal, which often causes danger; the coil sensor is arranged on the grounding wire, and due to the insulating joint of the high-voltage cable, the protective layer of the cable is discontinuous (direct grounding, protective grounding and cross interconnection grounding can occur respectively), and the like, the attenuation of signals on the grounding protective layer is large, and fault traveling wave signals cannot be effectively detected.
SUMMERY OF THE UTILITY MODEL
In view of the above, it is necessary to provide a cable fault detection device capable of measuring a cable fault safely and accurately at a low cost.
In a first aspect, the utility model provides a detection device of cable fault, include:
one end of the first coil is electrically connected with the signal acquisition unit, and the other end of the first coil is arranged on the outer layer of the cable body in a winding manner;
the second coil, the one end of second coil with the other end electric connection of first coil, the other end winding of second coil sets up in the skin of ground connection cable, warp the skin, with signal acquisition unit electric connection, the ground connection cable is the sheath ground connection part of cable body when terminal separation.
In one embodiment, the cable fault detection apparatus further includes a first annular supporting element, the first annular supporting element is sleeved on the outer layer of the cable body, and after the other end of the first coil winds around the first annular supporting element in a spiral manner along a reverse direction of the circumferential direction after going around a circle along the circumferential direction of the first annular supporting element from a preset initial position of the first annular supporting element, the first annular supporting element returns to the preset initial position.
In one embodiment, the cable fault detection apparatus further includes a second annular supporting member, the second annular supporting member is sleeved on an outer layer of the ground cable, and after the other end of the second coil winds around the second annular supporting member in a spiral manner along a reverse direction of the circumferential direction after winding around a circle along the circumferential direction of the second annular supporting member from a preset initial position of the second annular supporting member, the second coil returns to the preset initial position.
In one embodiment, the other end of the first coil is electrically connected to one end of the second coil through the first conductor of the second cable, and the other end of the second coil is electrically connected to the second conductor of the second cable.
In one embodiment, the other end of the second coil is electrically connected to the signal acquisition unit through the second conductor of the second cable and the first conductor of the first cable, and one end of the first coil is electrically connected to the signal acquisition unit through the first conductor of the first cable.
In one embodiment, the length of the first cable is greater than a first preset value, and the length of the second cable is greater than a second preset value.
In one embodiment, the first cable and the second cable are high frequency coaxial cables.
In one embodiment, the mutual inductance of the first coil is the same as the mutual inductance of the second coil.
In one embodiment, the signal acquisition unit is configured to convert the acquired signal into a transmission current of the cable, and send the fault information when the transmission current is greater than a preset threshold.
In a second aspect, the present invention further provides a cable fault detection system, including:
a cable body;
the utility model provides an in any one the device cable fault's detection device.
According to the cable fault detection device, the first coil is arranged on the cable body, the second coil is arranged on the grounding cable, the first coil is connected with the second coil, the sheath current in the cable body monitored by the coils and the current generated in the grounding cable can be mutually offset, the transmission current of the cable core is obtained, and whether the cable has a fault or not can be safely and accurately judged according to the size of the transmission current.
Drawings
FIG. 1 is a schematic diagram of a cable fault detection apparatus according to one embodiment;
fig. 2 is a schematic structural diagram of a cable fault detection device in one embodiment.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
In one embodiment, as shown in fig. 1, there is provided a cable fault detection apparatus including:
one end of the first coil is electrically connected with the signal acquisition unit, and the other end of the first coil is arranged on the outer layer of the cable body in a winding manner;
the cable body 101 includes a cable core 103 and a sheath 102, and the sheath 102 is a sealed metal sheath for preventing moisture from entering into the outer layer of the cable. In the power transmission process, the generation of induced voltage in the sheath of the high voltage cable is a common phenomenon in the power cable, and the induced voltage can generate sheath current in the sheath.
The embodiment of the utility model provides an in, cable fault's detection device includes first coil 104, and first coil is the coil that sets up on the cable body for the electric current that flows through in the detection cable body. One section of the coil is connected with the signal acquisition unit 109 and is used for transmitting the acquired signal to the signal acquisition unit 109, and the other end of the coil is arranged on the outer layer of the cable body in a winding manner and is used for detecting the current in the cable body in a manner of surrounding the cable body by winding into the coil.
The one end of second coil with the other end electric connection of first coil, the other end winding of second coil sets up in the skin of ground connection cable, warp outer, with signal acquisition unit electric connection, the ground connection cable is the sheath ground connection part of cable body when the terminal separation.
The embodiment of the present invention provides an embodiment, the detecting device of the cable fault further includes a second coil 106, the second coil is a coil disposed on the grounding cable 105, wherein the grounding cable 105 is a part of the cable body 101 separated from the grounding sheath when separating. In one example, the cable may separate the cable core and the ground cable at a predetermined position, wherein the ground cable is a portion of the cable body where the separated sheath is grounded. One end of the second coil is electrically connected with the other end of the first coil, so that the first coil and the second coil are connected in series; the second coil is arranged on the outer layer of the grounding cable in a winding mode and used for detecting the current in the grounding cable in a mode that the grounding cable is wound into the coil to surround. After the winding is finished, the other end of the second coil can be electrically connected with the signal acquisition unit and is used for transmitting the acquired signal to the signal acquisition unit together with one end of the first coil.
Wherein, the winding mode of the first coil and the second coil is usually limited. The limiting mode is as follows: by setting the winding directions of the two coils, when current passes through the cable, electromotive forces generated on the first coil and the second coil are opposite in direction.
In one example, since the cable body has a large diameter and the ground cable has a small diameter, the first coil wound around the cable body has a large diameter and the second coil wound around the cable body has a small diameter. In one example, the first coil may have an inner diameter of 120mm and the second coil may have an inner diameter of 40 mm. The two coils are connected in series through a high-frequency coaxial cable; and the serially connected coils are connected to the input end of the cable fault acquisition device through a high-frequency coaxial cable.
The embodiment of the utility model provides a, set up first coil on the cable body, set up the second coil on the ground connection cable to be connected first coil and second coil, the sheath electric current in the cable body that can make the coil monitor offsets each other with the electric current that ground connection cable produced, obtains the transmission current of cable core, thereby can be with lower costs and safe accurately judge whether the cable produces the trouble according to transmission current's size. And simultaneously, because the embodiment of the utility model provides a with the coil setting on cable body and ground connection cable, avoided installing the coil and appeared being close to the too near dangerous condition that leads to of insulating terminal on the cable core. The embodiment of the utility model provides a requirement is lower to the mounted position of coil, and the practicality becomes strong, especially at the installation of intermediate head department, and inserts the circuit simply, need not unnecessary joint interface.
In an embodiment, the cable fault detection apparatus further includes a first annular supporting member, the first annular supporting member is sleeved on the outer layer of the cable body, and after the other end of the first coil winds around the first annular supporting member in a spiral manner in a direction opposite to the circumferential direction after winding around a circle from a preset initial position of the first annular supporting member in the circumferential direction of the first annular supporting member, the first annular supporting member returns to the preset initial position.
The embodiment of the utility model provides an in, when the coil winding, still be provided with cyclic annular support piece, first cyclic annular support piece 201 cover is established at the skin of cable body, and first coil can twine on first cyclic annular support piece when the skin of cable body twines. In one example, the first annular support is a hollow circular ring. Wherein. The winding mode is that the other end of the first coil winds around the first annular supporting piece along the circumferential direction of the first annular supporting piece for a circle from any preset initial position of the annular supporting piece, and then spirally winds the first annular supporting piece along the reverse direction of the circumferential direction to return to the preset initial position of the annular supporting piece.
In an embodiment, the cable fault detection apparatus further includes a second annular supporting member, the second annular supporting member is sleeved on the outer layer of the ground cable, and after the other end of the second coil winds around the second annular supporting member in a direction opposite to the circumferential direction after winding around a circle from a preset initial position of the second annular supporting member in the circumferential direction of the second annular supporting member, the second coil winds around the second annular supporting member in a spiral manner to return to the preset initial position.
The embodiment of the utility model provides an in, when the coil winding, still be provided with cyclic annular support piece, the outer at ground connection cable is established to the cyclic annular support piece 202 cover of second, and the second coil can twine on the cyclic annular support piece of second when the skin of cable body twines. In one example, the second annular support is a hollow circular ring. The winding mode is that the other end of the second coil winds the second annular supporting piece along the circumferential direction of the second annular supporting piece for a circle from any preset initial position of the annular supporting piece, and then spirally winds the second annular supporting piece along the reverse direction of the circumferential direction to return to the preset initial position of the annular supporting piece.
The embodiment of the utility model provides a, provide cyclic annular support piece for the coil winding, can make things convenient for the winding of coil, the parameter of standard winding back coil can accurately restrict the coil parameter so that obtain the detected signal who wants.
In one embodiment, the other end of the first coil is electrically connected to one end of the second coil through a first conductor of a second cable, and the other end of the second coil is electrically connected to a second conductor of the second cable.
The embodiment of the utility model provides an in, the other end of first coil and the one end electric connection's of second coil mode are connected for the first conductor through in the second cable 107, and the one end at the first conductor of second cable 107 is connected to the other end of first coil, and the other end at the first conductor of second cable is connected to the one end of second coil. The other end of the second coil is connected to one end of a second conductor of the second cable after being wound around a ground cable.
In one embodiment, the other end of the second coil is electrically connected to the signal acquisition unit through the second conductor of the second cable and the first conductor of the first cable, and one end of the first coil is electrically connected to the signal acquisition unit through the first conductor of the first cable.
In the embodiment of the utility model, the other end of second coil is connected with the second conductor of second cable 107 earlier, then is connected with the signal acquisition unit through the first conductor of first cable 108, and the one end of first coil is connected with the signal acquisition unit through the first conductor of first cable 108.
The embodiment of the utility model provides a, through setting up first cable and second cable interconnect between first coil, second coil and the signal acquisition unit has been realized.
In one embodiment, the length of the first cable is greater than a first preset value, and the length of the second cable is greater than a second preset value.
The embodiment of the utility model provides an in, first cable 108 can be greater than a certain default, and the length of second cable 107 is also greater than a certain default. In one example, the preset value may be any length value within a controllable range.
The embodiment of the utility model provides a, the length of first cable and second cable all can be greater than the default, has reduced detection device's mounted position's restriction for detection device uses more convenient.
In one embodiment, the first cable and the second cable are high frequency coaxial cables.
In the embodiment of the utility model provides an in, first cable and second cable adopt high frequency coaxial cable.
The embodiment of the utility model provides a, carry out electric connection through adopting high frequency coaxial cable to first coil, second coil and signal acquisition unit, can make high frequency signal not produce great decay at the in-process of transmission for the signal that signal acquisition unit gathered is more accurate, has improved fault detection's accuracy.
In one embodiment, the mutual inductance of the first coil is the same as the mutual inductance of the second coil.
The embodiment of the utility model provides an in, when setting up first coil and second coil, the mutual inductance that needs control first coil and second coil is the same.
The embodiment of the utility model provides a, the same electromotive force that can control the sheath current through first coil and the electromotive force range that the sheath current through the second coil produced is the same, and the size is opposite that the mutual inductance coefficient of control first coil and second coil is the same to offset each other. Only the current of the cable core, namely the transmission current, is reserved, so that the influence of the current of the sheath layer can be eliminated, and the fault signal can be accurately acquired.
In one example, to enable the two coils to be connected in series to achieve sheath current cancellation, the turns and dimensions of the first and second coils should satisfy the following relationship:
U 1 ＝M 1 ×2×f×π×I m
U 2 ＝M 2 ×2×f×π×I m
wherein, U 1 Is the sheath voltage, U, output by the first coil 2 Is the voltage output by the second coil, M 1 Is the mutual inductance of the first coil, M 2 Is the mutual inductance of the second coil, f is the frequency of the signal of the measured sheath, I m Is the effective value of the current of the detected sheath. Therefore, if U is required 1 ＝U 2 Then M is required 1 ＝M 2 I.e. the mutual inductance of the first coil is equal to the mutual inductance of the second coil.
I.e. mu 0 ×N 1 ×S 1 /(2×π×R 1 )＝μ 0 ×N 2 ×S 2 /(2×π×R 2 )
Wherein, mu 0 Is a vacuum magnetic conductivity; n is a radical of 1 Number of turns of winding of coil 1, S 1 Is a wound wireCross-sectional area of the ring, R 1 Is the diameter of the coil 1; n is a radical of 2 Is the number of winding turns of coil 2, S 2 Is the cross-sectional area of the wound coil, R 2 The diameter of the coil 2.
After simplification, the following is obtained: n is a radical of 1 ×S 1 /R 1 ＝N 2 ×S 2 /R 2 。
The embodiment of the utility model provides a, it is the same to make the mutual inductance coefficient of two coils through the injecing of each parameter to first coil and second coil to the electromotive force that can control the sheath current production through first coil is the same with the electromotive force range that the sheath current through the second coil produced, and the size is opposite, thereby offsets each other. Only the current of the cable core, namely the transmission current, is reserved, so that the influence of the current of the sheath layer can be eliminated, and the fault signal can be accurately acquired.
In one embodiment, the signal acquisition unit is configured to convert the acquired signal into a transmission current of the cable, and send the fault information if the transmission current is greater than a preset threshold.
The embodiment of the utility model provides an in, the signal conversion that the signal acquisition unit will gather becomes the transmission current of cable to can judge whether the cable produces the trouble according to the size of judging transmission current. When the transmission current is larger than a preset threshold value, a fault traveling wave signal is generated, namely the cable is in fault at the moment, and the signal acquisition unit sends out fault information at the moment. It is understood that the preset threshold value here is a threshold value set by a user according to the magnitude of the transmission current at the time of cable safety and the transmission current at the time of failure.
The embodiment of the utility model provides a, through signal acquisition unit acquisition signal and change, judge whether break down and send trouble information. The embodiment of the utility model provides a can be to gathering fault signal and sending failure information to can make the information of acquireing the cable fault that relevant personnel can be timely.
The utility model also provides a detection system of cable fault, include:
a cable body;
the utility model provides an in any one the device cable fault's detection device.
In an embodiment of the present invention, the fault detection system includes a cable body, the component of the cable body includes but is not limited to cable core and sheath. The basic structure of the cable consists of four parts, namely a wire core, an insulating layer, a shielding layer and a protective layer, wherein the wire core is a conductive part of the power cable, is used for transmitting electric energy and is a main part of the cable; the insulation layer electrically isolates the wire cores from the ground and the wire cores of different phases, ensures electric energy transmission and is an indispensable component in a power cable structure; the shielding layer, the power cable of 15kV and above generally has a conductor shielding layer and an insulation shielding layer; and a protective layer for protecting the power cable from external impurities and moisture, and preventing external force from directly damaging the power cable. The cable can be classified into a medium-low voltage power cable, a high voltage cable, an ultra-high voltage cable and an extra-high voltage cable according to voltage class, and can be classified into an alternating current cable and a direct current cable according to current system. At a predetermined position, the sheath of the cable body is separated and grounded to become a grounding cable. The cable fault detection device further comprises a device for detecting the cable fault, and the implementation scheme for solving the problem provided by the device is the same as the implementation scheme recorded in the method, so that specific limitations can be referred to the limitations of the device for detecting the cable fault in the above description, and further description is omitted here.
The technical features of the above embodiments can be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the above embodiments are not described, but should be considered as the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above-mentioned embodiments only represent some embodiments of the present invention, and the description thereof is specific and detailed, but not construed as limiting the scope of the embodiments of the present invention. It should be noted that, for those skilled in the art, without departing from the concept of the embodiments of the present invention, several variations and modifications can be made, which are within the scope of the embodiments of the present invention. Therefore, the protection scope of the embodiments of the present invention should be subject to the appended claims.
Claims (10)
1. A cable fault detection device, comprising:
one end of the first coil is electrically connected with the signal acquisition unit, and the other end of the first coil is arranged on the outer layer of the cable body in a winding manner;
the second coil, the one end of second coil with the other end electric connection of first coil, the other end winding of second coil sets up in the skin of ground connection cable, warp the skin, with signal acquisition unit electric connection, the ground connection cable is the sheath ground connection part of cable body when terminal separation.
2. The apparatus according to claim 1, further comprising a first annular supporting member, wherein the first annular supporting member is sleeved on the outer layer of the cable body, and after the other end of the first coil winds around the first annular supporting member in a spiral manner along a direction opposite to the circumferential direction after going around a circle along the circumferential direction of the first annular supporting member from a preset initial position of the first annular supporting member, the first annular supporting member returns to the preset initial position.
3. The apparatus according to claim 1, further comprising a second annular supporting member, wherein the second annular supporting member is sleeved on an outer layer of the grounding cable, and after the other end of the second coil winds around the second annular supporting member in a spiral manner along a direction opposite to the circumferential direction after winding around a circle along the circumferential direction of the second annular supporting member from a preset initial position of the second annular supporting member, the second coil winds around the second annular supporting member in a spiral manner to return to the preset initial position.
4. The apparatus for detecting a cable fault according to claim 1, wherein the other end of the first coil is electrically connected to one end of a second coil through a first conductor of a second cable, and the other end of the second coil is electrically connected to a second conductor of the second cable.
5. The cable fault detection device according to claim 4, wherein the other end of the second coil is electrically connected to the signal acquisition unit through the second conductor of the second cable and the first conductor of the first cable, and one end of the first coil is electrically connected to the signal acquisition unit through the first conductor of the first cable.
6. The apparatus according to claim 5, wherein the length of the first cable is greater than a first preset value, and the length of the second cable is greater than a second preset value.
7. The cable fault detection device of claim 5 or 6, wherein the first cable and the second cable are high frequency coaxial cables.
8. The cable fault detection device of claim 1, wherein the first coil has a mutual inductance that is the same as the mutual inductance of the second coil.
9. The cable fault detection device of claim 1, wherein the signal acquisition unit is configured to convert the acquired signal into a transmission current of the cable, and to send fault information if the transmission current is greater than a preset threshold.
10. A cable fault detection system, comprising:
a cable body;
a cable fault detection apparatus according to any one of claims 1 to 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202123361246.6U CN217443474U (en) | 2021-12-29 | 2021-12-29 | Cable fault detection device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202123361246.6U CN217443474U (en) | 2021-12-29 | 2021-12-29 | Cable fault detection device |
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| Publication Number | Publication Date |
|---|---|
| CN217443474U true CN217443474U (en) | 2022-09-16 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202123361246.6U Active CN217443474U (en) | 2021-12-29 | 2021-12-29 | Cable fault detection device |
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| Country | Link |
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| CN (1) | CN217443474U (en) |
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2021
- 2021-12-29 CN CN202123361246.6U patent/CN217443474U/en active Active
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