CN108020709A - A kind of three core power cable electriferous state detection devices - Google Patents
A kind of three core power cable electriferous state detection devices Download PDFInfo
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- CN108020709A CN108020709A CN201711278297.8A CN201711278297A CN108020709A CN 108020709 A CN108020709 A CN 108020709A CN 201711278297 A CN201711278297 A CN 201711278297A CN 108020709 A CN108020709 A CN 108020709A
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- cable
- circuit
- signal
- core power
- electriferous state
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/145—Indicating the presence of current or voltage
- G01R19/15—Indicating the presence of current
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
- G01H17/00—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves, not provided for in the preceding groups
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- General Physics & Mathematics (AREA)
- Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
- Electric Cable Installation (AREA)
Abstract
The present invention relates to a kind of three core power cable electriferous state detection devices, including：Be sheathed on the outside of three core power cable to be detected and for detect three core power cable vibration signals micro-vibration detection sensor unit, for detection signal is handled signal condition amplifying unit, be used for transmission the connection cables of detection signal and be connected through connection cables with the signal condition amplifying unit and the detection host of testing result is provided.A kind of three core power cables electriferous state detection device proposed by the present invention, realizes using vibration signal detection cable electriferous state, has easy to operate, device is portable, tests the characteristics of accurate, it is ensured that the personal safety of line data-logging personnel, shorten cable power off time, improve power supply reliability.
Description
Technical field
The present invention relates to a kind of three core power cable electriferous state detection devices.
Background technology
In recent years, power cable was applied increasingly extensive in China's power grid, and usage amount sharply increases.Cable run or wall scroll
Or it is a plurality of, laid with various ways such as direct-burried, pipeline, raceway groove, tunnel, gallerys.In the regular maintenance of cable run often
Encounter due to the situation that geography information is imperfect or cable marking board is not known of cable radiation, at this time to ensure operating personnel's
Safety is, it is necessary to the electriferous state of detection cable.
Current commonly used test equipment is the operation principle based on measurement cable surrounding magnetic field, and flexible coil is sleeved on electricity
On cable, the electric current in live electric cable produces alternating magnetic field, the induced voltage in flexible coil.It is known that by the measurement of voltage
Whether there is electric current to flow through in cable, so as to disclose cable electriferous state indirectly.Power cable electriferous state inspection both domestic and external at present
Survey device and be all based on pure measurement of magnetic field method.Basic principle is electric current to be flowed through in powered cable conductor, around
Magnetic field is produced, a coil is covered on cable（Commonly referred to as Rogowski coil）, magnetic field can produce induced electricity on coil
Kinetic potential, measurement induced potential can measure magnetic field, so that the electric current in indirect detection to cable conductor.
However, it have also discovered many examples judged by accident or be difficult to detection cable electriferous state in：For the short of zero load
Cable, due to electric current very little, corresponding surrounding magnetic field is also just very weak, it is difficult to measures, the judgement to electriferous state causes difficulty, surveys
Examination instrument is difficult to effectively detect；The cable of cable or more close contacts for direct-burried, coil can not be sleeved on cable under test；
Also can be difficult for three-core cable, the reason is that the electric current of cable three-core cable cancels each other, around the induced electricity of a coil measurement
Gesture also can very little.
In recent years, the limitation of existing method was more obvious：With the increase of cable dosage, a plurality of cable can be close parallel
Laying, coil is sleeved on a cable will be difficult.
In view of the above circumstances, high performance cable electriferous state detection device is designed and made, lifts cable electriferous state
Judge reliability, be current cable operation, maintenance and safety in production in extremely important problem.
The content of the invention
It is an object of the invention to provide a kind of three core power cable electriferous state detection devices, to overcome in the prior art
There are the defects of.
To achieve the above object, the technical scheme is that：A kind of three core power cable electriferous state detection devices, bag
Include：It is sheathed on the outside of three core power cable to be detected and the micro-vibration detection for detecting three core power cable vibration signals senses
Device unit, for detection signal handled signal condition amplifying unit, be used for transmission detection signal connection cables with
And it is connected through the connection cables with the signal condition amplifying unit and the detection host of testing result is provided.
In an embodiment of the present invention, the micro-vibration detection sensor unit includes a clamp type structure shell；The pincers
The madial wall of formula structural housing is provided with a plurality of micro-vibrations for being used to detect the three core power cables vibration signal to be detected
Sensor；The vibrative sensor is connected with the signal condition amplifying unit.
In an embodiment of the present invention, the clamp type structure shell includes left anchor ear and right anchor ear；The left anchor ear with
And connection of the right anchor ear by being correspondingly arranged in top and bottom latches connection；The vibrative sensor is arranged at the left side
The madial wall of anchor ear and right anchor ear；The sidepiece of the right anchor ear is additionally provided with one and is used to set the signal condition amplifying unit
Circuit box.
In an embodiment of the present invention, the signal condition amplifying unit include sequentially connected input impedance conversion device,
Three road signal conditioning circuits, gating circuit, amplifying circuit and output impedance matching unit.
In an embodiment of the present invention, the connection cables use a multicore cable with shielded layer, and are passed including signal
Defeated line and power cord.
In an embodiment of the present invention, the detection host includes a shell body and the sampling being arranged in the shell body
Circuit, central processing unit, memory circuitry and power circuit；The connection cables are through opening up and leading at the top of the shell body
Hole is connected with the sample circuit and the power circuit；The central processing unit respectively with the sample circuit, the storage
Deposit circuit and the power circuit；The central processing unit is also opened in the groove of the shell body upper surface with being arranged at
Display and button are connected.
In an embodiment of the present invention, the power circuit includes a decompression voltage regulator and a lithium battery；The drop
Pressure regulator circuit is connected by the power cord in the connection cables with the conditioning amplifying circuit.
Compared to the prior art, the invention has the advantages that：
1st, the present invention is improved to unloaded cable or very short cable by using the method for measurement cable body vibration signal
Detection sensitivity.
2nd, the present invention enhances the applicability of detection device, solves by using the method for measurement cable body vibration signal
Determined the existing instrument based on magnetic-field measurement principle face direct-buried cable or more with cable be in close contact situation under be difficult into
The problem of row test.
3rd, compared with existing test device, sensor smaller, configuration are more flexible used in the present invention.It is contemplated that this hair
New three core power cables live testing device in bright has in the operation, maintenance and safety in production of electric power enterprise cable run
Have wide practical use.
Brief description of the drawings
Fig. 1 is a kind of composition schematic diagram of three core power cables electriferous state detection device of the present invention.
Fig. 2 is micro-vibration detection sensor unit base used in a kind of three core power cable electriferous state detection devices of the invention
This structure diagram.
Fig. 3 is the basic of signal condition amplifying unit used in a kind of three core power cables electriferous state detection device of the present invention
Structure composition schematic diagram.
Fig. 4 is a kind of three core power cable electriferous state detection devices detection main computer unit basic structure group used of the invention
Into schematic diagram.
Fig. 5 is that a kind of three core power cable electriferous state detection devices of the invention are by vibrative sensor detection cable
No powered basic principle figure.
Embodiment
Below in conjunction with the accompanying drawings, technical scheme is specifically described.
The present invention provides a kind of three core power cable electriferous state detection devices, including：It is sheathed on three cores electric power to be detected
On the outside of cable and for detect three core power cable vibration signals micro-vibration detection sensor unit, for detection signal into
Row processing signal condition amplifying unit, be used for transmission detection signal connection cables and through the connection cables and the letter
Number conditioning amplifying unit is connected and provides the detection host of testing result.
In the present embodiment, as shown in Figure 1, mainly including micro-vibration detection sensor unit 11, signal condition amplification list
Member 12, connection cables unit 13 and detection main computer unit 14 form.The device is mainly measured by micro-vibration detection sensor
The vibration signal arrived, by signal processing and analysis compare, draw the cable whether the state of charging operation.Its cardinal principle
For：
As shown in figure 5, when three-core cable is in normal operating condition, the current balance type of its internal three-phase, overall externally performance
For electric current and be 0, then the magnetic field that externally shows and be 0, the subrange inside cable, its electric current and be not 0, the scope memory
In magnetic field.When it is I51 to conduct electric current in a phase, there are shielded layer outside the Ampereconductors, electric current generation can be masked
Magnetic field, but shielded layer stacks for thin copper layer, there are gap, can have a part of transmission magnetic field, in addition on the copper shield
There is also displacement current, can also produce certain magnetic field, and similarly there are displacement current I52, the electricity on the shielded layer of adjacent phase
Stream can be subject to magnetic field force to act in above-mentioned magnetic field：.Therefore, which shakes
It is dynamic.If the cable is single-ended powered situation, and running light situation, without conduction electric current in cable, but still can there are position
Electric current is moved, lesser degree of periodic vibration is produced in the cable which can equally make.If the cable is completely with out electric shape
State, then will not produce periodic vibration.Therefore, the judgement of the cable electriferous state according to the analysis of vibration signal, can be drawn.
Further, in the present embodiment, micro-vibration detection sensor unit includes a clamp type structure shell；Clamp type structure
The madial wall of shell is provided with a plurality of vibrative sensors for being used to detect the three core power cables vibration signal to be detected；
Vibrative sensor is connected with signal condition amplifying unit.Clamp type structure shell includes left anchor ear and right anchor ear；Left anchor ear with
And connection of the right anchor ear by being correspondingly arranged in top and bottom latches connection；Vibrative sensor be arranged at left anchor ear and
The madial wall of right anchor ear；The sidepiece of right anchor ear is additionally provided with a circuit box for being used for setting signal conditioning amplifying unit.Such as Fig. 2 institutes
Show, be the basic structure composition schematic diagram of micro-vibration detection sensor unit, mainly by three circumferentially equally distributed Gao Ling
Lock 23 is confined in sensitivity vibrative sensor 21, jaw type shell 22, connection, and late-class circuit box 24 forms.High sensitivity is micro-
Vibrating sensor measurement object is to have displacement current in adjacent phase-displaced current magnetic field and conduction electric current by a phase in cable
Transmit caused vibration signal in magnetic field.
Further, in the present embodiment, as shown in figure 3, being formed for the basic structure of signal condition amplifying unit, the letter
Number conditioning amplifying circuit is installed in the late-class circuit box of micro-vibration detection sensor unit, mainly by input impedance conversion device
31, three road signal conditioning circuits 32, gating circuit 33, amplifying circuit 34 and output impedance matching unit 35 form.Three road tune
Reason circuit is respectively connected to three high sensitivity vibrative sensors, and after sensor detects vibration signal, it is dynamic to form switch
Make, relevant voltage signal is formed after modulate circuit, by controlling gating circuit 33, select later observation and record wherein a certain
The signal on road, which is amplified by amplifier, easy to later observation.
Further, in the present embodiment, amplifier output is connected by connection cables with detection main computer unit.The cable
Using the multi channel signals conducting wire with shielding, both transmission measurement data to host, while control command and power supply power supply also by
The connection cables are transmitted.The connection cables length uses 1.5 meters, using 6 core of Lemo types.
Further, in the present embodiment, detecting host includes a shell body and the sampling being arranged in the shell body
Circuit, central processing unit, memory circuitry and power circuit；Connection cables are through opening up and the through hole at the top of shell body and sampling
Circuit and power circuit are connected；Central processing unit respectively with sample circuit, storage circuit and the power circuit；Centre
Reason device is also connected with being arranged at the display being opened in the groove of shell body upper surface and button.Power circuit includes a decompression
Regulator circuit and a lithium battery；Decompression voltage regulator is connected by the power cord in connection cables with conditioning amplifying circuit.
Central processor unit judges that the tested cable is by analyzing Mean Oscillation value, repetition step-by-step counting and multiphase comparison threshold value
It is no to be in charging operation state.
Further, as shown in figure 4, for detection main computer unit basic structure composition, sampling unit 41 is consisted predominantly of, in
Central processor unit 42, memory cell 43, display unit 44 and power module 45.Sampling unit 41 is connect by line cable
Mouth is connected to the output of conditioning amplifying unit, while the decompression voltage regulator of power module is single to conditioning amplification also by the interface
Member power supply.Central processing unit uses ARM processors, and signal handling capacity is quick, accurately, small by carrying out one to data-signal
The mean value calculation of section time, excludes the interference vibration signal occurred at random, then records this group of data to memory, Ke Yizai
The data of gating circuit analysis record another two sensor are controlled by arm processor, adjacent electricity can also be recorded by selection
The related data of cable, since the data of storage are only average pulse amplitude and repetition, memory can be expired using 256M
Foot requires.When measurement data be 0, and repetition be 50Hz or 50Hz odd-multiple when, it can be determined that the cable is in band
Electricity condition.By the measurement to surrounding cables, corresponding numerical value is recorded, can be with when this cable differs more than 20 times with maximum
Judge that this cable is likely to be at non-loaded electriferous state.
Further, in the present embodiment, device proposed by the present invention is also equipped with following features：
（1）Brand-new principle is employed, measurement is mechanical oscillation, is a mechanical quantity, is no longer traditional electrical quantity-magnetic
.
（2）It make use of two kinds of physical phenomenons relevant with mechanical oscillation at the same time.
（3）Using there is interaction force between electric current.For three-core cable：The cable conductor of 50Hz changes, between electric current
Interaction cable conductor can be vibrated.
（4）Using there is electrostatic force between the conductor of different voltages.For single or three-core cable：Current－carrying conductor
The high pressure of tens of thousands of volt or hundreds of thousands volt 50Hz changes is operated in, the metallic shield of cable or sheath are usually operated at zero electricity of ground connection
Pressure condition.Electrostatic force between cable conductor and metallic shield or sheath can excite the vibration of cable.
（5）The device uses brand-new detection method, judges cable by the measurement of the vibration signal to cable body
Electriferous state, sensitivity and the applicability of detection device are enhanced, as in the operation and maintenance work of three core power cables
Indispensable instrument, for improve cable electriferous state determined level, ensure operating personnel personal safety and fast quick-recovery
Power supply is of great significance.
（6）The shortcomings that brand-new measuring device of the present invention ensures to overcome conventional device：
（a）For short non-loaded cable, electric current is weak to be will also result in vibration and dies down, but vibrate as caused by electrostatic force completely with
Cable length is unrelated, it is ensured that the reliability of detection；
（b）For three-core cable, also ensured that with 1 vibrating sensor along the traverse measurement of cable outer surface and measure vibration, with 3
A vibrating sensor, their measured value corroborates each other, as a result more reliable；
（c）For the crowded cable laid together, a vibrating sensor is the somewhere for being easily close to surface, is directly solved
Conventional method of having determined Rogowski coil sensor can not be sleeved on the difficulty for carrying out test on cable.
Above is presently preferred embodiments of the present invention, all changes made according to technical solution of the present invention, caused function are made
During with scope without departing from technical solution of the present invention, protection scope of the present invention is belonged to.
Claims (7)
- A kind of 1. three core power cable electriferous state detection devices, it is characterised in that including：It is sheathed on three cores electric power electricity to be detected On the outside of cable and it is used for the micro-vibration detection sensor unit of three core power cable vibration signals of detection, for being carried out to detection signal The signal condition amplifying unit of processing, be used for transmission detection signal connection cables and through the connection cables and the signal Conditioning amplifying unit is connected and provides the detection host of testing result.
- 2. a kind of three core power cables electriferous state detection device according to claim 1, it is characterised in that described micro- to shake Dynamic detection sensor unit includes a clamp type structure shell；The madial wall of the clamp type structure shell is provided with a plurality of for examining Survey the vibrative sensor of the three core power cables vibration signal to be detected；The vibrative sensor and the signal condition Amplifying unit is connected.
- A kind of 3. three core power cables electriferous state detection device according to claim 2, it is characterised in that the jaw type Structural housing includes left anchor ear and right anchor ear；The left anchor ear and right anchor ear pass through at the top of being correspondingly arranged in and bottom Connection lock connection；The vibrative sensor is arranged at the madial wall of the left anchor ear and right anchor ear；The right anchor ear Sidepiece is additionally provided with a circuit box for being used to set the signal condition amplifying unit.
- A kind of 4. three core power cables electriferous state detection device according to claim 1, it is characterised in that the signal Nurse one's health amplifying unit include sequentially connected input impedance conversion device, three road signal conditioning circuits, gating circuit, amplifying circuit with And output impedance matching unit.
- A kind of 5. three core power cables electriferous state detection device according to claim 1, it is characterised in that the connection Cable uses a multicore cable with shielded layer, and including signal transmssion line and power cord.
- A kind of 6. three core power cables electriferous state detection device according to claim 1, it is characterised in that the detection Host includes a shell body and the sample circuit, central processing unit, memory circuitry and the power supply that are arranged in the shell body Circuit；The connection cables are through opening up and the through hole at the top of the shell body and the sample circuit and the power circuit phase Even；The central processing unit respectively with the sample circuit, the storage circuit and the power circuit；The center Processor is also connected with being arranged at the display being opened in the groove of the shell body upper surface and button.
- A kind of 7. three core power cables electriferous state detection device according to claim 6, it is characterised in that the power supply Circuit includes a decompression voltage regulator and a lithium battery；The decompression voltage regulator passes through the power cord in the connection cables It is connected with the conditioning amplifying circuit.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201711278297.8A CN108020709A (en) | 2017-12-06 | 2017-12-06 | A kind of three core power cable electriferous state detection devices |
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| CN201711278297.8A CN108020709A (en) | 2017-12-06 | 2017-12-06 | A kind of three core power cable electriferous state detection devices |
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| CN201711278297.8A Pending CN108020709A (en) | 2017-12-06 | 2017-12-06 | A kind of three core power cable electriferous state detection devices |
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Cited By (4)
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| CN109000786A (en) * | 2018-08-01 | 2018-12-14 | 安徽康能电气有限公司 | A kind of conductive intelligent linearly coupled monitoring device |
| CN110247340A (en) * | 2019-06-03 | 2019-09-17 | 广州供电局有限公司 | Monitor anchor ear device |
| CN114222898A (en) * | 2019-08-13 | 2022-03-22 | 日本电气株式会社 | Optical fiber sensing system, optical fiber sensing equipment and power failure detection method |
| CN115993558A (en) * | 2023-03-22 | 2023-04-21 | 西安交通大学城市学院 | Electrical property measuring device of high-low voltage power distribution cabinet |
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| CN114222898A (en) * | 2019-08-13 | 2022-03-22 | 日本电气株式会社 | Optical fiber sensing system, optical fiber sensing equipment and power failure detection method |
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