CN104714155B - A kind of detection to direct current XLPE cable shelf depreciation and apparatus for evaluating and method - Google Patents

A kind of detection to direct current XLPE cable shelf depreciation and apparatus for evaluating and method Download PDF

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Publication number
CN104714155B
CN104714155B CN201510053432.3A CN201510053432A CN104714155B CN 104714155 B CN104714155 B CN 104714155B CN 201510053432 A CN201510053432 A CN 201510053432A CN 104714155 B CN104714155 B CN 104714155B
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discharge
cable
partial discharge
detection
temperature
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CN104714155A (en
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徐阳
康强
陈浩
傅明利
侯帅
田野
卓然
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Xi an Jiaotong University
Power Grid Technology Research Center of China Southern Power Grid Co Ltd
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Xi an Jiaotong University
Power Grid Technology Research Center of China Southern Power Grid Co Ltd
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Abstract

The invention discloses a kind of detection to direct current XLPE cable shelf depreciation and apparatus for evaluating and method, including tested cable and the DC partial discharge detection means for obtaining local discharge signal;The both ends of tested cable are connected with high direct voltage output device and current output device;Temperature-detecting device is laid with tested cable.The present invention, using suitable for exchange Partial Discharge Detection and the means of analysis, has filled up DC partial discharge detection and the blank of analysis method according to DC partial discharge and the difference for exchanging shelf depreciation.The present invention considers influence of the temperature for shelf depreciation, using the measurement result that measurement of partial discharge is carried out under the unloaded or off-line state by dummycable at normal temperatures by the way of carrying out the measurement result of measurement of partial discharge under with load state using current output device dummycable and being combined comprehensive analysis, more fully comprehensive assessment is carried out for cable insulation situation.

Description

A kind of detection to direct current XLPE cable shelf depreciation and apparatus for evaluating and method
Technical field
The present invention relates to a kind of detection to direct current XLPE cable shelf depreciation and apparatus for evaluating and method.
Background technology
Crosslinked polyethylene (XLPE) power cable is because its is simple in construction, load capacity is strong, laying is easy, operation maintenance side Just, the advantages that excellent insulation performance, simple production process, it is widely used in power system.With XLPE cable circuit Extensive use, important component of the transition joint as power cable, usage amount are consequently increased.But cable intermediate joint is same When be also transmission line of electricity accident multiple position, its reliability directly affects the safety of electric power system.Cable intermediate joint due to Poor material, coarse manufacture craft, scene installation lack of standardization and many factors such as electricity, heat, mechanical stress, can form latency Insulation defect, potential potential safety hazard is brought for the operation of power network.Operating experience and research show:The cable connector design phase Existing all kinds of typical defects can produce shelf depreciation mostly, therefore the Partial Discharge Detection of cable connector is for high-tension cable Normal operation and failure predication have very important significance.
And now with the quick increase of offshore wind farm installed capacity and the continuous development of HVDC Transmission Technology, direct current Loss is low by it for cable, is easy to advantage, the demands such as progress power adjusting rapidly improves.Particularly changed in recent years based on voltage source The development of device VSC (voltagesourceconverter) technology of stream, it is greatly facilitated based on crosslinked polyethylene (XLPE) absolutely The development of the flexible direct current cable of edge material, for oil paper cable, XLPE direct current cables have it is more environmentally friendly, and And the advantages that simple, is laid in manufacture.Usual direct current cables circuit is long, voltage class is high, and gigantic project, importance is high, therefore right Its working condition is detected, it is ensured that it is necessary in normal working condition.In view of direct current cables with exchanging The different method of operation of cable, directly apply mechanically ac cable detection means may and it is improper, currently for direct current cables detect Analysis means are still very deficient.
The important means that Partial Discharge Detection detects as ac cable, can be as the important hand of reflection dielectric level Section.For XLPE direct current cables, when its cable major insulation or annex generation defect and may equally be produced under certain voltage Shelf depreciation, therefore Partial Discharge Detection is carried out to direct current cables system and equally can be found that the defects of it there may be.And office Portion's discharge examination, DC partial discharge have significant difference with exchanging local discharge characteristic, are compared to exchange shelf depreciation, directly It is relatively low to flow the repetitive rate of shelf depreciation, and only electric discharge amplitude and inter-spike intervals, without the concept at discharge phase angle, therefore Exchange what is commonly used among Analysis of Partial DischargeIt is local that analysis mode related to phase angle-q-n etc. just can not all be applied to direct current Electric discharge.Need to be analyzed with special means for DC partial discharge, this respect is at present still with respect to blank.
Electric field is distributed the geometry point for depending on cable capacitance electric field in a insulating layer for high-voltage alternating cable Cloth, and it is assumed that dielectric constant can be readily obtained when being a constant not varied with temperature, thus plus loading and transport Row is heated to when operation temperature that it is constant all the time, although actual conditions dielectric constant can change a lot, Its influence almost can be ignored.
Electric field in the insulation of high-voltage alternating cable may generally be expressed as:
Wherein:EAC(r)=radius be r place AC field distribution (kV/mm or MV/m)
U0The design voltage of=cable, i.e., voltage (kV) on dielectric;Phase voltage is represented in exchange field
R=radius distances (mm)
ri=cable insulation inside radius (mm)
r0=cable insulation outer radius (mm)
For high voltage direct current cable, its Electric Field Distribution is changed with temperature and time, and this is due to direct current cables electric field Distribution is determined by resistance at this under steady state conditions, that is, is decided by the resistivity of insulation, and dielectric resistivity is in turn Dependent on temperature and electric-field intensity, in the case of only also there is no thermograde inside non-loading cable, the electric field of direct current cables Distribution situation is essentially identical with exchanging.
Electric field in high-voltage DC cable insulating may generally be expressed as:
Wherein
Wherein:
The temperature coefficient (1/K or 1/ DEG C) of a=electrical conductivity
The stress coefficient (mm/kV or m/MV) of b=electrical conductivity
Wherein:
WCJoule thermal losses (w/m) in=conductor
λTThe thermal conductivity of=insulation
The change of local field strength can mainly be reflected in the change of electric discharge repetitive rate at discharge position, and due to the thermal effect of electric field It should influence, the change of electric field can cause the change of temperature again in turn, so as to cause the coupled relation of electric field and temperature, for putting Electricity produces complicated influence.
The content of the invention
It is an object of the invention to solve above-mentioned the problems of the prior art, there is provided a kind of that direct current XLPE cable is locally put The detection of electricity and apparatus for evaluating and method.
To achieve these goals, the present invention is achieved using following technical scheme:
A kind of DC partial discharge measurement apparatus, including tested cable and the direct current office for obtaining local discharge signal Portion's discharging detection device;The both ends of tested cable are connected with high direct voltage output device and current output device;On tested cable It is laid with temperature-detecting device.
Industrial frequency AC 220V is risen to power frequency high voltage U by the high direct voltage output device using power frequency testing transformert, warp Cross silicon stack D and carry out halfwave rectifier, then concatenate current-limiting resistance R and charged to filter capacitor C, be finally output on tested cable.
The temperature-detecting device is using the PT100 thermocouples being laid on tested cable surface and cable accessory.
The current output device uses punching transformer, and the junction of punching transformer and tested cable, which is provided with, to be used for Prevent the grading shield of corona;Pressure regulator is also associated with punching transformer.
The DC partial discharge detection means includes detection impedance measurement loop, HF current transformer and ultrasound and passed Sensor;Detect impedance measurement loop and tested cable is connected to using the regulation in IEC60270 standards, HF current transformer On ground wire, sonac is close to tested cable connector.
A kind of detection and appraisal procedure to direct current XLPE cable shelf depreciation, comprise the following steps:
1) in the case where current output device is closed, tested cable is pressurizeed using high direct voltage output device, Setting test voltage is boosted to, records device for detecting temperature displays temperature;
2) DC partial discharge detection means is coupled local discharge signal;
3) to the local discharge signal denoising after coupling;
4) the electric discharge amplitude Q in local discharge signal is extracted under time domain, with function of time t functional form exhibition Open, form the Q-t figure progress DC partial discharge analyses for the rule that changed with time for performance electric discharge amplitude;
5) three-dimensional spectrum being applied in the case of DC partial discharge analysis is established;
6) by carrying out DC partial discharge to the tested cables of multiple different defects, and by obtained different H (Q, Δ t) Three-dimensional spectrum is preserved with corresponding electric discharge type, establishes fingerprint base;By obtained H, (Q, Δ t) images are carried out with electric discharge image Contrast, realizes the judgement of type the defects of to DC partial discharge;
7) local discharge signal obtained to step 3) carries out fast Fourier change, and shelf depreciation letter is analyzed under frequency domain Distribution number in the range of different frequency range, by analyzing peak frequencies to actual discharge or noise, internal discharge or corona discharge And the defects of producing electric discharge type is judged;
8) high direct voltage output device is adjusted, 0kV is reduced the voltage to, firing current output device punching transformer, adjusts Current dummycable band carries situation, observes cable and its attachment surface temperature in device for detecting temperature, makes its surface temperature liter Height is to 70 DEG C or more, with the situation under the conditions of dummycable heavy-duty service;
9) after temperature reaches stable, recycle high direct voltage output device to pressurize tested sample of cable, boost To setting test voltage, device for detecting temperature displays temperature is recorded;
10) step 2)~step 7) detection and analysis process is repeated, measurement is completed, electric current is closed after being measured Output device and high direct voltage output device, tested sample, which is stood, to be reduced temperature and effectively discharge 24 hours.
In the step 2), the local discharge signal that sensor is coupled to is amplified and filtering process, then performed Step 3).
In the step 3), denoising is caught by pulse signals, will be with applying DC voltage polarity phase Anti- signal filtering.
In the step 5), the specific method for the three-dimensional spectrum being applied in the case of DC partial discharge is analyzed is established such as Under:
Time interval Δ t between discharge pulse during DC partial discharge and its preamble discharge pulse replaces phase angle, establish different discharge times and account for relation H (Q, Δ t), wherein the width that discharges between the percentage i.e. power-discharging density H of total discharge time Value Q has been extracted among Q-t figures are drawn;Extraction for adjacent pulse time interval Δ t, according to discharge threshold Qmin's Set, using the pulse more than discharge threshold as effective discharge pulse, record each discharge pulse in Q-t respective coordinates parameters (Qi, ti), wherein Qi>Qmin, and Δ t=ti-ti-1Obtain Δ t.
Compared with prior art, the invention has the advantages that:
The present invention is according to DC partial discharge and the difference for exchanging shelf depreciation, using suitable for exchanging Partial Discharge Detection With the means of analysis, DC partial discharge detection and the blank of analysis method have been filled up.It is low according to DC partial discharge repetitive rate The characteristics of, 30-60 minute long-time measurement of partial discharges are proposed, and the general of phase angle is corresponded to according to DC partial discharge no pulse Read, be not suitable for DC partial discharge point among Analysis of Partial Discharge method with phase angle correlation analysis means so as to cause to exchange Analysis, thus use based on Q-t figures, the research mode that N-t, N-Q figure aid in, while with time interval between two adjacent discharge pulses Δ t replaces phase angle formation to be applied to DC partial discharge analyzing three-dimensional spectrogram.Simultaneously according to DC partial discharge signal pulse list Special, the central accuracy that opposite polarity pulse is gone as interference divided by ensures measurement of denoising of polarity.The present invention examines Consider influence of the temperature for shelf depreciation, react on because temperature significantly affects for the Electric Field Distribution under direct current and directly The change for repetitive rate of discharging, thus using will dummycable at normal temperatures is unloaded or off-line state under carry out measurement of partial discharge Measurement result is mutually tied with being carried out the measurement result of measurement of partial discharge under with load state using current output device dummycable The mode of comprehensive analysis is closed, more fully comprehensive assessment is carried out for cable insulation situation.
Brief description of the drawings
Fig. 1 is the test schematic of the present invention;
Fig. 2 is the experiment process figure of the present invention;
Fig. 3 is DC partial discharge analysis method flow chart of the present invention;
Fig. 4 is the ambient noise waveform of the embodiment of the present invention;
Fig. 5 is that the ambient noise waveform of the embodiment of the present invention corresponds to frequency domain distribution figure;
Fig. 6 is the clock B of embodiment of the present invention impulse waveform;
The impulse waveform that Fig. 7 is the clock B of the embodiment of the present invention corresponds to frequency domain distribution figure;
Fig. 8 is the Q-t spectrograms of the embodiment of the present invention;
Fig. 9 is that the N-t wherein N of the embodiment of the present invention are arranged to discharge time in 1min;
Figure 10 is N-Q spectrograms of the present invention, and wherein N is arranged to discharge time in 1min;
Figure 11 is Q- Δs t spectrograms of the present invention.
Embodiment
The present invention will be further described in detail below in conjunction with the accompanying drawings:
Referring to Fig. 1, the present invention provides the detection and analysis of a kind of shelf depreciation combination temperature for XLPE direct current cables Method, because DC partial discharge signal compared to exchange local discharge signal has electric discharge, repetitive rate is low, discharge off pulse is corresponding Significant differences such as phase angle, therefore measured in the present invention using 30-60min long-times DC partial discharge, it is another use using Q-t figures as Main combination is applied to the common H of novel three-dimensional (Q, Δ t) the progress pattern-recognitions of DC partial discharge analysis.Due under direct current, absolutely Electric Field Distribution in edge depends on the distribution of resistivity, and resistance can vary with temperature generation significant change, electric at this so as to influence Distribution, at discharge position the change of local field strength can mainly be reflected in the change for repetitive rate of discharging.And due to the heat of electric field Effects, the change of electric field can cause the change of temperature again in turn, so as to cause the coupled relation of electric field and temperature, for Electric discharge produces complicated influence.The present invention considers influence of the temperature change for electric discharge, and temperature is included into comprehensive examination and evaluation scope.
The circuit arrangement of the present invention:
(1) high direct voltage output device:The unavailable high voltage direct current generator of direct current compression system, because it can be introduced substantially Impulse type disturbs, and is approached with partial discharge pulse band limits, so as to cause measurement result signal to noise ratio to be unable to reach 2:1 Standard even floods discharge pulse.The present invention produces high direct voltage using halfwave rectifier, will first by power frequency testing transformer Industrial frequency AC 220V rises to power frequency high voltage UT, through it is pressure-resistant be at least 4.3UT(being breakdown voltage 2/3 according to design voltage nargin) Silicon stack carries out halfwave rectifier, and concatenation current-limiting resistance R is charged to filter capacitor C, and filter capacitor C is pressure-resistant to be at least Wherein silicon stack through-current capability is determined by silicon stack model, and the present invention recommends to use 3A.Current-limiting resistance and filtering capacitance are according to high Correlation technique is determined by ripple requirement and test voltage, electric current in voltage test technology, wherein according to standard GB/T/T: 16927.1 related contents, DC high potential test equipment ripple factor should be less than 3%.Parallel resistance after HVDC presser unit Divider, wherein resitstance voltage divider show actually applied DC voltage numerical value.
(2) current output device:Punching transformer is mainly that cable and joint are bearing high-tension while providing big electricity Stream, with dummycable operating load.Cable is during band carries, because heating effect of current causes temperature to raise, analog temperature shadow Ring.Punching transformer is with installing grading shield additional to prevent corona at cable connection.
(3) device for detecting temperature:Thermocouple PT100 is laid in cable surface and cable accessory, to cable surface and Its annex carries out temperature monitoring.
(4) DC partial discharge measurement apparatus:The mode that DC partial discharge detection obtains local discharge signal is divided into receipts The electrical measuring method of electric signal is produced during collection shelf depreciation and collects generation such as sound, light non-electrical signal during shelf depreciation Non- electrical measuring method.The present invention is applied to electrical measuring method and sound detection.For electrical measuring method, the pulse current recommended suitable for IEC60270 Method (detect impedance and carry out local discharge signal detection), HF current transformer (HFCT) during shelf depreciation for obtaining Electric signal be collected, and sound detection is suitable for use with piezoelectric as sensor, and mechanical oscillation signal is converted into electricity Signal.Provided in detection impedance measurement loop reference IEC60270 standards, HF current transformer installation site is connected to ground connection On line, sonac is close to tested cable connector, and (such as tested cable is furnished with cable connector or terminal annex, is preferably placed with In on annex).
Specific detection of the invention comprises the following steps with appraisal procedure:
(1) current output device punching transformer is closed i.e. not in the case of output current first, is exported using high direct voltage Device pressurizes to tested sample of cable, boosts to agreement test voltage, records device for detecting temperature displays temperature.
(2) DC partial discharge measurement apparatus is coupled local discharge signal.Put for the part under DC voltage Electricity, because repetitive rate is relatively low, time of measuring needs to reach 30-60 minutes.
(3) to improve measurement accuracy, signal transacting link can be added after sensor, the signal that sensor is coupled to enters The necessary amplification of row and filtering.Electrical measuring method is such as used, wave filter can will be accessed under stronger environment by being disturbed in environment electromagnetics, will be passed The signal that sensor is coupled to is filtered, and filter parameter should be selected according to actual noise environment.As discharge signal is weaker Then, amplifier is added later in filtering, signal is amplified, it is optional corresponding narrower for field test amplifier band, Recommend frequency band in 1MHz-500MHz, and used in laboratory and then use wide-band amplifier.For being measured using ultrasonic method, Sensor is followed by preamplifier, and multiplication factor is recommended in 10kHz-2000kHz in more than 20dB, working frequency.
(4) for in-site measurement, noise jamming is an important factor for limitation Partial Discharge Detection uses, and denoising is very Key, DC partial discharge measurement among, apply DC voltage be unipolarity therefore local discharge signal be also unipolarity, for DC partial discharge signal is based on its unipolar feature, will be with applying DC voltage by being caught for pulse signal Opposite polarity signal is considered as noise signal and filtered, so as to reduce the influence of noise.
(5) signal being coupled to by sensor, effective discharge signal is obtained by signal transacting and denoising.Due to DC partial discharge lacks phase angle compared to exchange shelf depreciationConcept, therefore exchange Analysis of Partial Discharge among and phase angle Correlation analysis means it is inapplicable, it is necessary to re-establish the analysis means suitable for DC partial discharge among direct current.It is right In the analysis method of DC partial discharge, the present invention be with time domain for local discharge signal in electric discharge amplitude Q carry Take, deployed with function of time t functional form, form Q-t figures as main analysis means, performance electric discharge amplitude is with the time Changing rule.Threshold value should be first set among actual measurement, threshold value is arranged on background noise level, and is ensured simultaneously not More than electric discharge amplitude 1/2 to ensure that signal to noise ratio reaches 2:1, and then it is judged as effective discharge pulse more than setting threshold value.Separately It is outer to establish relation between the electric discharge repetitive rate N in one minute and test period t, N-t figures are formed, performance electric discharge repetitive rate is with the time Changing rule.Among DC partial discharge detection, average minute clock electric discharge repetitive rate just produces effective not less than being once N >=1 Partial discharge phenomenon, voltage during sample generation N=1 is just set then to be considered as the DC partial discharge starting voltage of sample.It is right In Q-t figure relations, such as under certain test voltage, discharge capacity Q is very big and interior holding is stable at the trial or discharges repetitive rate N very Keep stable greatly and within the time, or increase with the time, Q, N are in obvious ascendant trend, should be for tested sample insulation status Paid close attention to.
(6) due to direct current cables system, it is possible to create many reason for electric discharge, such as major insulation scratches, stress cone dislocation Factors, because the discharge characteristic of different electric discharge types has significant difference, and its development trend also has difference therefore phase Countermeasure is answered to refer to the defects of different type.It is usually used in carrying out for different electric discharge types among exchange Partial Discharge Detection The PRPD spectrograms of pattern-recognition due to lacking phase angle under direct currentConcept and can not use.The present invention, which establishes, is applied to direct current office Three-dimensional spectrum in the case of portion's Discharge analysis.Between discharge pulse during DC partial discharge and its preamble discharge pulse Time interval Δ t replaces phase angle, build between different discharge times account for the percentage i.e. power-discharging density H of total discharge time and close It is H (Q, Δ t), wherein electric discharge amplitude Q has been extracted among step (5) Q-t figures are drawn, and between the adjacent pulse time Every Δ t extraction, according to discharge threshold QminSetting using the pulse more than discharge threshold as effective discharge pulse, record respectively put Electric pulse is in Q-t respective coordinates parameters (Qi,ti), wherein Qi>Qmin, and Δ t=ti-ti-1Obtain Δ t.
(7) by carrying out DC partial discharge for the test product of a large amount of different defects, and by obtained different H (Q, Δ t) Three-dimensional spectrum is preserved with corresponding electric discharge type, establishes fingerprint base.For obtained H (Q, Δ t) images, by scheming with electric discharge Judged i.e. pattern-recognition hence for defect type as being contrasted.
(8) present invention is carried out using what is obtained for step (5) by signal transacting and the discharge signal of denoising in addition Fast Fourier changes FFT, and distribution of the discharge signal in the range of different frequency range is analyzed under frequency domain.Recording different types are put The waveform component of electrical waveform different frequency is different, therefore for actual discharge or can be made an uproar by the analysis for peak frequencies etc. The defects of sound, internal discharge or corona discharge and generation are discharged type is judged.
(9) high direct voltage output device is adjusted, 0kV is reduced the voltage to, firing current output device punching transformer, adjusts Current dummycable band carries situation, observes cable and its attachment surface temperature in device for detecting temperature, makes its surface temperature liter Height is to 70 DEG C or more with the situation under the conditions of dummycable heavy-duty service.
(10) after temperature reaches stable, recycle high direct voltage output device to pressurize tested sample of cable, rise Agreement test voltage is depressed into, records device for detecting temperature displays temperature.After come again step (2)-step (8) and tested and analyzed Journey, measurement is completed, current output device and high direct voltage output device are closed after being measured, tested sample, which is stood, makes temperature Reduce and carry out effectively electric discharge 24 hours.
The technological thought of above content only to illustrate the invention, it is impossible to protection scope of the present invention is limited with this, it is every to press According to technological thought proposed by the present invention, any change done on the basis of technical scheme, claims of the present invention is each fallen within Protection domain within.

Claims (7)

  1. A kind of 1. DC partial discharge measurement apparatus, it is characterised in that:Including tested cable and for obtaining shelf depreciation letter Number DC partial discharge detection means;The both ends of tested cable are connected with high direct voltage output device and current output device; Temperature-detecting device is laid with tested cable;The high direct voltage output device uses power frequency testing transformer by industrial frequency AC 220V rises to power frequency high voltage Ut, halfwave rectifier is carried out by silicon stack D, then concatenate current-limiting resistance R and charged to filter capacitor C, It is finally output on tested cable;The DC partial discharge detection means is mutual including detection impedance measurement loop, high frequency electric Sensor and sonac;Impedance measurement loop is detected using the regulation in IEC60270 standards, HF current transformer card It is connected on the ground wire of tested cable, sonac is close to tested cable connector.
  2. 2. DC partial discharge measurement apparatus according to claim 1, it is characterised in that:The temperature-detecting device uses It is laid in tested cable surface and the PT100 thermocouples on cable accessory.
  3. 3. DC partial discharge measurement apparatus according to claim 1, it is characterised in that:The current output device uses The junction of punching transformer, punching transformer and tested cable is provided with the grading shield for preventing corona;Punching becomes Pressure regulator is also associated with depressor.
  4. A kind of 4. detection and assessment to direct current XLPE cable shelf depreciation using claim 1-3 any one described devices Method, it is characterised in that comprise the following steps:
    1) in the case where current output device is closed, tested cable is pressurizeed using high direct voltage output device, boosted To setting test voltage, device for detecting temperature displays temperature is recorded;
    2) DC partial discharge detection means is coupled local discharge signal;
    3) to the local discharge signal denoising after coupling;
    4) the electric discharge amplitude Q in local discharge signal is extracted under time domain, deployed with function of time t functional form, Form the Q-t figure progress DC partial discharge analyses for the rule that changed with time for performance electric discharge amplitude;
    5) three-dimensional spectrum being applied in the case of DC partial discharge analysis is established;
    6) by carrying out DC partial discharge to the tested cable of multiple different defects, and (Q, Δ t) are three-dimensional by obtained different H Spectrogram is preserved with corresponding electric discharge type, establishes fingerprint base;By obtained H (Q, Δ t) images with electric discharge image contrasted, Realize the judgement of type the defects of to DC partial discharge;
    7) local discharge signal obtained to step 3) carries out fast Fourier change, and local discharge signal is analyzed under frequency domain and is existed Distribution in the range of different frequency range, by analyze peak frequencies to actual discharge or noise, internal discharge or corona discharge and The defects of producing electric discharge type is judged;
    8) high direct voltage output device is adjusted, reduces the voltage to 0kV, firing current output device punching transformer, regulation electricity Flow field simulation banded cable carries situation, observes cable and its attachment surface temperature in device for detecting temperature, is increased to its surface temperature 70 DEG C or more, with the situation under the conditions of dummycable heavy-duty service;
    9) after temperature reaches stable, recycle high direct voltage output device to pressurize tested sample of cable, boost to and set After determining test voltage, device for detecting temperature displays temperature is recorded;
    10) step 2)~step 7) detection and analysis process is repeated, measurement is completed, electric current output is closed after being measured Device and high direct voltage output device, tested sample, which is stood, to be reduced temperature and effectively discharge 24 hours.
  5. 5. the detection and appraisal procedure according to claim 4 to direct current XLPE cable shelf depreciation, it is characterised in that:Institute State in step 2), the local discharge signal that sensor is coupled to is amplified and filtering process, then perform step 3).
  6. 6. the detection to direct current XLPE cable shelf depreciation and appraisal procedure, its feature according to claim 4 or 5 exist In:In the step 3), denoising is caught by pulse signals, by the letter opposite with applying DC voltage polarity Number filtering.
  7. 7. the detection and appraisal procedure according to claim 4 to direct current XLPE cable shelf depreciation, it is characterised in that institute State in step 5), the specific method for establishing the three-dimensional spectrum being applied in the case of DC partial discharge is analyzed is as follows:
    Time interval Δ t between discharge pulse during DC partial discharge and its preamble discharge pulse replaces phase angleBuild Found different discharge times and account for relation H (Q, Δ t), wherein electric discharge amplitude Q exists between the percentage i.e. power-discharging density H of total discharge time Q-t figures have been extracted among drawing;Extraction for adjacent pulse time interval Δ t, according to discharge threshold QminSetting, Using the pulse more than discharge threshold as effective discharge pulse, each discharge pulse is recorded in Q-t respective coordinates parameters (Qi,ti), wherein Qi>Qmin, and Δ t=ti-ti-1Obtain Δ t.
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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
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CN108254659A (en) * 2017-12-25 2018-07-06 国网电力科学研究院武汉南瑞有限责任公司 The shelf depreciation of cable and the combined detection system of leakage current and method under high direct voltage
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
CN109164358B (en) * 2018-08-22 2019-10-25 云南电网有限责任公司电力科学研究院 A kind of cable integral insulation dampness fault simulation and test method
CN109212392B (en) * 2018-09-25 2021-01-08 上海交通大学 Method and system for identifying partial discharge defect fault of direct current cable and Caffe convolutional neural network
CN109298267A (en) * 2018-11-01 2019-02-01 国网浙江省电力有限公司舟山供电公司 Crosslinked polyethylene ac cable is used for the reliability test system of flexible DC transmission
CN109490730A (en) * 2018-12-19 2019-03-19 国网北京市电力公司 Cable discharge detection method, device, storage medium and processor
CN110988612A (en) * 2019-11-08 2020-04-10 广东电网有限责任公司 Cable head insulation performance online monitoring system and method

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4445596A1 (en) * 1994-12-20 1996-06-27 Hagenuk Telecom Gmbh Partial discharge measurement method for e.g. high voltage cable
CN102735977A (en) * 2012-07-12 2012-10-17 四川大学 Electrical-thermal aging device of cable accessories under high voltage and high current and test method thereof
CN203365619U (en) * 2013-08-19 2013-12-25 广东弘光电力工程有限公司 System for detecting and positioning partial discharge of cable oscillation waves
CN203405538U (en) * 2013-08-07 2014-01-22 广东电网公司东莞供电局 Partial discharge test system for cable
CN103954890A (en) * 2014-04-10 2014-07-30 国家电网公司 DC partial discharge detection device and method for converter transformer

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100693634B1 (en) * 2005-03-17 2007-03-14 엘에스전선 주식회사 Sensor integrated at the cable joints for sensing partial discharge of cable and fabrication method therefor

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4445596A1 (en) * 1994-12-20 1996-06-27 Hagenuk Telecom Gmbh Partial discharge measurement method for e.g. high voltage cable
CN102735977A (en) * 2012-07-12 2012-10-17 四川大学 Electrical-thermal aging device of cable accessories under high voltage and high current and test method thereof
CN203405538U (en) * 2013-08-07 2014-01-22 广东电网公司东莞供电局 Partial discharge test system for cable
CN203365619U (en) * 2013-08-19 2013-12-25 广东弘光电力工程有限公司 System for detecting and positioning partial discharge of cable oscillation waves
CN103954890A (en) * 2014-04-10 2014-07-30 国家电网公司 DC partial discharge detection device and method for converter transformer

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
便携式电缆局部放电检测仪器——高压谐振电源装置的设计;刘亚赤;《电器工业》;20041231(第06期);正文第36页左栏第二节第1段,图2-1 *

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