CN103558532A - Partial discharge on-line detection system of high-voltage crosslinked polyethylene power cable - Google Patents

Partial discharge on-line detection system of high-voltage crosslinked polyethylene power cable Download PDF

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Publication number
CN103558532A
CN103558532A CN201310585938.XA CN201310585938A CN103558532A CN 103558532 A CN103558532 A CN 103558532A CN 201310585938 A CN201310585938 A CN 201310585938A CN 103558532 A CN103558532 A CN 103558532A
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China
Prior art keywords
power cable
cable
current transformer
discharge
frequency
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Pending
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CN201310585938.XA
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Chinese (zh)
Inventor
张来
赵高帅
高毅
武娇文
王婧
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State Grid Corp of China SGCC
State Grid Tianjin Electric Power Co Ltd
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State Grid Corp of China SGCC
State Grid Tianjin Electric Power Co Ltd
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Priority to CN201310585938.XA priority Critical patent/CN103558532A/en
Publication of CN103558532A publication Critical patent/CN103558532A/en
Pending legal-status Critical Current

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Abstract

The invention relates to a partial discharge on-line detection system of a high-voltage crosslinked polyethylene power cable. The system comprises a high-frequency current transformer used for being coupled with discharge signals in a ground wire of an accessory of the cable, and the high-frequency current transformer is connected with a high-speed data collecting card through a coaxial cable. The high-speed data collecting card converts collected analog signals into digital signals and outputs the digital signals to an upper computer. The upper computer is connected with a human-computer interface, an input keyboard, a printout device, an external storage device and an alarming device respectively, and power is provided for the whole system by a UPS power supply outputting alternating currents. According to the partial discharge on-line detection system of the high-voltage crosslinked polyethylene power cable, the selected high-frequency current transformer is a signal collecting sensor, and the partial discharge on-line detection system has the advantages of being convenient to install and use, high in SNR, convenient to carry and suitable for portable devices; the data size is small in each time of collecting, and therefore the whole collecting, calculating, analyzing and judging processes can be finished within a short time.

Description

HV XLPE Power Cable PD On-Line Measurement System
Technical field
The invention belongs to the shelf depreciation online measuring technique field of HV XLPE Power Cable annex, particularly a kind of HV XLPE Power Cable PD On-Line Measurement System.
Background technology
Along with the quickening of China's urban network reconstruction and upgrading paces, power cable is more and more applied in defeated, the power distribution network of each electric pressure.At present, the 110kV putting into operation and above Voltage Cable Lines Construction have reached thousands of kilometers.In recent years, cross-inked polyethylene power cable is with its superior electric property, good heat, mechanical effect, and the feature such as convenient for installation and maintenance is widely used in electric system.After putting into operation, due to defect causes such as the impurity of introducing in cable production, transportation, installation and operational process, bubble, burr, projections, or be subject to for a long time the erosion infiltration of moisture, moisture, chemical substance, and cause cable insulation aging, have a strong impact on cable operation life.Within one quite long period, the domestic periodic withstand voltage test of the many employings of detection to HV XLPE Power Cable insulation.The method is more effective to open defect, but helpless for those need develop the insulation thin spot that the several years just progressively manifests aging sign.In recent years, the cross-inked polyethylene power cable insulation diagnosis technology based on partial discharge monitoring or detection technique more and more receives publicity.Shelf depreciation refers to occur in the non-penetrability electric discharge phenomena in cable body insulation or annex.In shelf depreciation process, the electronics ionizing out, negative ions obtain compared with macro-energy under electric field force effect, when they strike insulating material, can cause the chemical bond rupture of material, and atarting material degraded is insulation accelerated aging.In addition, the dielectric heat at point of discharge place is serious, can make insulating material burn or melt, and causes dielectric conductance and loss to increase, and accelerates equally insulation ag(e)ing.Shelf depreciation process also can produce many active products, and corrosion insulator, makes dielectric behavior deteriorated.And the electric discharge of continuous demolition and all can make insulation form fine fisssure by the gases at high pressure of discharge generation, formation electric branch is aging.Visible, shelf depreciation behavior and its safe condition of power cable are closely related.Shelf depreciation information and then the residing duty of judgement cable insulation of by on-line monitoring or detection method, measuring cable are significant for operation power department.
Detection research for cross-inked polyethylene power cable insulated local discharge is carried out for a long time, and in the sixties in last century, existing researchist and engineering technical personnel carry out exploration work in this field.But to succeed in developing the time more late due to the cross-inked polyethylene power cable of 110kV and above, active time only more than 30 years so far, has 50 years above ripe use experiences and possesses perfect insulation ag(e)ing detection method unlike oil-filled cable.Therefore, for become at present the cross-inked polyethylene power cable of mainstream applications in China, develop its corresponding partial discharge monitoring or detection means, there is more significantly engineering significance.
The Partial Discharge Detection of cross-inked polyethylene power cable is inseparable with the development of sensor technology.Through the development of nearly half a century, the detection means of shelf depreciation is greatly progressive.In fact, engineering staff is when carrying out the detection of local discharge signal, and all kinds of physical phenomenons that produce while always utilizing shelf depreciation to occur, comprise sound, optical, electrical, heat and chemical effect etc.At present, the Partial Discharge Detection means that have been widely used have pulse current method, bridge method, radio interference voltage method, and the non-electro-detection method such as supercritical ultrasonics technology, Infrared survey.In recent years, domestic and international researchist and engineering technical personnel's focus is mainly placed on on-line monitoring or the detection technique of cross-inked polyethylene power cable shelf depreciation.Because local discharge signal is faint, waveform is complicated and changeable, very easily by ground unrest and outside electromagnetic interference noise, is flooded, and designing the sensor that a kind ofly can effectively suppress electromagnetic noise, pick up desirable local discharge signal is to carry out the online basis of detecting of shelf depreciation.At present, the HF current transformer based on Luo-coil principle is widely used, by Rational choice ferrite magnetic core material, optimizes wire winding and parameter, can obtain the local discharge signal pick-up transducers of high s/n ratio.
In cross-inked polyethylene power cable system, due to cable accessory structure relative complex, its Electric Field Distribution is very inhomogeneous, is the thin spot that is easy to cause shelf depreciation.Research shows, the shelf depreciation behavior of power cable concentrates in annex mostly.Therefore, cross-inked polyethylene power cable annex is carried out to shelf depreciation and detect online the security important in inhibiting to cognitive cable system.At present, existing researchist is classified as three major types by the shelf depreciation type occurring in cable accessory, i.e. corona discharge, creeping discharge and internal discharge.And every kind of electric discharge type is different to the degree of damage of cable insulation, how simple and efficient differentiation electric discharge belongs to any type, is the Practical Project problem that operations staff is extremely concerned about.
In order to distinguish different types of electric discharge type, the discharge waveform feature that need first cause variety classes cable insulation defect is studied and rule, and local discharge characteristic extracts.Over more than 30 year, later multiple discharge characteristic extracting method is suggested, and comprising: Φ-q-n spectrogram method, electric discharge statistical nature parametric method, fractal characteristic parameter method, single waveform character parametric method, image moment characteristic parameter method etc.Said method all needs the data to collecting to carry out the statistical computation of large amount of complex, consuming time longer, is suitable for the assistant analysis of background system.For the occasion of online detection Real-time Obtaining metrical information and feature, seem also inapplicable.Adopt more succinct effectively, calculate short method consuming time and distinguish electric discharge type, be the requirement of power cable PD On-Line Measurement System.
Summary of the invention
The object of the invention is for the deficiencies in the prior art, and propose a kind of HV XLPE Power Cable PD On-Line Measurement System.
The present invention solves its technical matters and takes following technical scheme to realize:
A kind of HV XLPE Power Cable PD On-Line Measurement System, this system comprises the HF current transformer for coupling cable annex ground wire discharge signal, HF current transformer is connected with high-speed data acquisition card by concentric cable, high-speed data acquisition card is exported to host computer after converting the simulating signal collecting to digital signal, host computer is connected with human interface devices, input keyboard, print out equipment, External memory equipment and panalarm respectively, and whole system is powered by the ups power that exchanges output.
And, described HF current transformer is directly connected on cable accessory ground wire, and HF current transformer is for adopting the HF current transformer based on Luo-coil principle, and response frequency is 100kHz-30MHz, sensitivity is not less than 10mV, and resolution is not less than 1mV.
And the concentric cable length that connects HF current transformer and high-speed data acquisition card is no more than 5m, wave impedance is 50 Ω.
And described high-speed data acquisition card sampling rate is not less than 60MHz, can select sampling rate 80MHz as a kind of preferred embodiment.
And, described host computer is implemented Fourier transform in order to the data to collecting, extract the energy information of high, medium and low frequency range, which kind of electric discharge there is in comprehensive judgement, differentiate the most at last result and deliver to human interface devices demonstration, host computer further comprises display module, database and analysis module is set, and display module is for showing typical discharge signal single pulse time domain waveform, frequency domain decomposition waveform and frequency-division section statistical nature and the historical data of being extracted by data acquisition; Database is for storing frequency-division section statistical parameter, single pulse amplitude, the frequency domain parameter of discharge signal; Analysis arranges module for capture card sample frequency, frequency range division threshold value, discharge signal trigger collection threshold value and the setting of database storage condition are set.
And described panalarm is the alarm buzzer being connected with host computer, the trigger pip triggering that hummer is sent by host computer realizes Feng Ming and reports to the police.
And described External memory equipment is solid state hard disc, for storing discharge characteristic data, comprise frequency-division section statistical parameter, single pulse amplitude, frequency domain parameter and typical Discharge pulse waveform.
Advantage of the present invention and good effect are
1, to choose HF current transformer be picking up signal sensor in the present invention, have easy to install, signal to noise ratio (S/N ratio) is high, the advantage such as easy to carry, and the expansibility of this portable system is improved.
2, the present invention does not need additional power current mutual inductor to pick up the power-frequency voltage reference signal in cable conductor, makes the structure of whole system more succinct.
3, the present invention adopts impulse discharge trigger action mode, and each data volume gathering is little, without configuration mass storage, is also convenient to the analytical calculation of host computer.Whole collection, calculating, analysis and deterministic process are completed equal within a short period of time, be suitable for the requirement of portable set.
4, the present invention can expand powerful software systems, comprises display module, database and analysis module is set, and can design collection, analytical parameters, and historical data, diagnostic result are consulted to comparison.
5, the invention provides the printing function of analysis result.
6, the present invention adopts full touch screen to control, show, interface is more directly perceived, succinct, complete function.
7, the present invention detects safety, rapid, accurate, is convenient to staff's operation, and equipment volume is little, lightweight, is convenient to carrying and carries, and local discharge characteristic is distinguished obvious, is easy to diagnose.
Accompanying drawing explanation
Fig. 1 is system architecture schematic diagram of the present invention.
Embodiment
Below in conjunction with accompanying drawing, the invention process is further described, following examples are descriptive, are not determinate, can not limit protection scope of the present invention with this.
The present invention proposes a kind of 110kV based on impulse discharge pulse waveform frequency domain character and the HV XLPE Power Cable annex PD On-Line Measurement System of above, when adopting HF current transformer to pick up three kinds of typical discharge modes (corona, along face, inside) impulse discharge pulse waveform, the feature of its frequency spectrum in high, medium and low frequency range distributes different, can identify three kinds of discharge modes.
A kind of HV XLPE Power Cable PD On-Line Measurement System, as shown in Figure 1, this system comprises the HF current transformer for coupling cable annex ground wire discharge signal, HF current transformer is connected with high-speed data acquisition card by concentric cable, high-speed data acquisition card is exported to host computer after converting the simulating signal collecting to digital signal, and host computer is connected with human interface devices, input keyboard, print out equipment, External memory equipment and panalarm respectively.
Wherein, HF current transformer is directly connected on cable accessory ground wire, HF current transformer is the HF current transformer based on Luo-coil principle, response frequency is 100kHz-30MHz, sensitivity is not less than 10mV, and resolution is not less than 1mV, during its work, when having local discharge signal to flow through ground wire, can produce at the output terminal of HF current transformer corresponding output voltage signal.
Wherein, the concentric cable length that connects HF current transformer and high-speed data acquisition card is no more than 5m, and wave impedance is 50 Ω.
Wherein, high-speed data acquisition card sampling rate is not less than 60MHz, in real work, can optionally select concrete sampling rate, as considers sampling rate requirement and system storage requirement, can select sampling rate 80MHz.
Wherein, host computer, in order to the data enforcement Fourier transform to collecting, extracts the energy information of high, medium and low frequency range, and comprehensive which kind of electric discharge of judgement generation, differentiates the most at last result and delivers to human interface devices demonstration.
Wherein, human interface devices adopts capacitive touch screen as human interface devices, by this interface, the sample frequency of high-speed data acquisition card can be set, the development trend of the times of collection of pulse signal, storage and enquiry of historical data, analysis discharge characteristic, and provide diagnostic result.
Wherein, panalarm is the alarm buzzer being connected with host computer, and the trigger pip triggering that hummer is sent by host computer realizes Feng Ming and reports to the police.
Wherein, host computer comprises display module, database and analysis module is set, and display module is for showing typical discharge signal single pulse time domain waveform, frequency domain decomposition waveform and frequency-division section statistical nature and the historical data of being extracted by data acquisition; Database is for storing frequency-division section statistical parameter, single pulse amplitude, the frequency domain parameter of discharge signal; Analysis arranges module for capture card sample frequency, frequency range division threshold value, discharge signal trigger collection threshold value and the setting of database storage condition are set.
Wherein, External memory equipment is solid state hard disc, for storing discharge characteristic data, comprises frequency-division section statistical parameter, single pulse amplitude, frequency domain parameter and typical Discharge pulse waveform.
Wherein, in this system, further comprise supply module, supply module can adopt and exchange output uninterruption power source UPS, power supply duration 1.5 hours; Also can be connected directly to grid side alternating current 220V power supply.

Claims (7)

1. a HV XLPE Power Cable PD On-Line Measurement System, it is characterized in that: this system comprises the HF current transformer for coupling cable annex ground wire discharge signal, HF current transformer is connected with high-speed data acquisition card by concentric cable, high-speed data acquisition card is exported to host computer after converting the simulating signal collecting to digital signal, host computer is connected with human interface devices, input keyboard, print out equipment, External memory equipment and panalarm respectively, and whole system is powered by the ups power that exchanges output.
2. HV XLPE Power Cable PD On-Line Measurement System according to claim 1, it is characterized in that: described HF current transformer is directly connected on cable accessory ground wire, HF current transformer is for adopting the HF current transformer based on Luo-coil principle, response frequency is 100kHz-30MHz, sensitivity is not less than 10mV, and resolution is not less than 1mV.
3. HV XLPE Power Cable PD On-Line Measurement System according to claim 1, is characterized in that: the concentric cable length that connects HF current transformer and high-speed data acquisition card is no more than 5m, and wave impedance is 50 Ω.
4. HV XLPE Power Cable PD On-Line Measurement System according to claim 1, is characterized in that: described high-speed data acquisition card sampling rate is not less than 60MHz, as a kind of preferred embodiment, can select sampling rate 80MHz.
5. HV XLPE Power Cable PD On-Line Measurement System according to claim 1, it is characterized in that: described host computer is implemented Fourier transform in order to the data to collecting, extract high, in, the energy information of low-frequency range, which kind of electric discharge there is in comprehensive judgement, differentiate the most at last result and deliver to human interface devices demonstration, host computer further comprises display module, database and analysis arrange module, display module is for showing the typical discharge signal single pulse time domain waveform of being extracted by data acquisition, frequency domain decomposition waveform and frequency-division section statistical nature and historical data, database is for storing frequency-division section statistical parameter, single pulse amplitude, the frequency domain parameter of discharge signal, analysis arranges module for capture card sample frequency, frequency range division threshold value, discharge signal trigger collection threshold value and the setting of database storage condition are set.
6. HV XLPE Power Cable PD On-Line Measurement System according to claim 1, it is characterized in that: the alarm buzzer of described panalarm for being connected with host computer, the trigger pip triggering that hummer is sent by host computer realizes Feng Ming and reports to the police.
7. HV XLPE Power Cable PD On-Line Measurement System according to claim 1, it is characterized in that: described External memory equipment is solid state hard disc, be used for storing discharge characteristic data, comprise frequency-division section statistical parameter, single pulse amplitude, frequency domain parameter and typical Discharge pulse waveform.
CN201310585938.XA 2013-11-20 2013-11-20 Partial discharge on-line detection system of high-voltage crosslinked polyethylene power cable Pending CN103558532A (en)

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Cited By (8)

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Publication number Priority date Publication date Assignee Title
CN104458821A (en) * 2014-12-12 2015-03-25 国家电网公司 Time-domain pulse detection method of water inlet state of cross-linked cable connector
CN104535909A (en) * 2015-01-12 2015-04-22 国家电网公司 Crosslinked polyethylene power cable accessory partial discharge pattern recognition system
CN106353657A (en) * 2016-11-28 2017-01-25 国网福建省电力有限公司 High-voltage direct current cable partial discharge intelligent monitoring device and monitoring method
CN107505543A (en) * 2017-08-11 2017-12-22 河南天通电力有限公司 Based on mesolow cable local discharge on-line monitoring system
CN108614196A (en) * 2018-03-29 2018-10-02 浙江工业大学之江学院 A kind of high-voltage cable that can detect electric discharge automatically
CN109116203A (en) * 2018-10-31 2019-01-01 红相股份有限公司 Power equipment partial discharges fault diagnostic method based on convolutional neural networks
CN109521337A (en) * 2018-11-24 2019-03-26 天津大学 A kind of electrostrictive polymer branch characteristic measuring device and method based on ultrasonic method
CN112578247A (en) * 2020-12-18 2021-03-30 广东电网有限责任公司中山供电局 Cable oscillatory wave partial discharge measurement system

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CN1580797A (en) * 2004-05-17 2005-02-16 西安交通大学 Power cable local discharge on-line monitoring method and device
CN101162246A (en) * 2006-10-13 2008-04-16 中国华北电力集团公司天津市电力公司 Crosslinking polyethylene-insulated cable insulation diagnostic apparatus
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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104458821A (en) * 2014-12-12 2015-03-25 国家电网公司 Time-domain pulse detection method of water inlet state of cross-linked cable connector
CN104535909A (en) * 2015-01-12 2015-04-22 国家电网公司 Crosslinked polyethylene power cable accessory partial discharge pattern recognition system
CN106353657A (en) * 2016-11-28 2017-01-25 国网福建省电力有限公司 High-voltage direct current cable partial discharge intelligent monitoring device and monitoring method
CN107505543A (en) * 2017-08-11 2017-12-22 河南天通电力有限公司 Based on mesolow cable local discharge on-line monitoring system
CN108614196A (en) * 2018-03-29 2018-10-02 浙江工业大学之江学院 A kind of high-voltage cable that can detect electric discharge automatically
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CN109521337A (en) * 2018-11-24 2019-03-26 天津大学 A kind of electrostrictive polymer branch characteristic measuring device and method based on ultrasonic method
CN112578247A (en) * 2020-12-18 2021-03-30 广东电网有限责任公司中山供电局 Cable oscillatory wave partial discharge measurement system

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Application publication date: 20140205