CN104714155A - Detection and evaluation device and method for partial discharge of direct current XLPE cables - Google Patents
Detection and evaluation device and method for partial discharge of direct current XLPE cables Download PDFInfo
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- CN104714155A CN104714155A CN201510053432.3A CN201510053432A CN104714155A CN 104714155 A CN104714155 A CN 104714155A CN 201510053432 A CN201510053432 A CN 201510053432A CN 104714155 A CN104714155 A CN 104714155A
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Abstract
The invention discloses a detection and evaluation device and method for partial discharge of direct current XLPE cables. The detection and evaluation device comprises a detected cable and a direct current partial discharge detection device used for acquiring partial discharge signals. The two ends of the detected cable are connected with a direct current high-voltage output device and a current output device. A temperature detecting device is arranged on the detected cable. According to the detection and evaluation device and method, the means suitable for alternating current partial discharge detection and analysis is adopted according to the difference of direct current partial discharge and alternating current partial discharge, and the blank of a direct current partial discharge detection and analysis method is filled. The influence of temperatures on particle discharge is considered, the comprehensive analysis mode that the measurement result of partial discharge measurement which is conducted in the state of simulating cable no-load or being in an offline state under the normal temperatures and the measurement result of partial discharge measurement which is conducted of simulating the cable in an on-load state by the current output device are combined is adopted, and the insulation condition of the cable is more comprehensively evaluated.
Description
Technical field
The present invention relates to a kind of test and assessment device and method to direct current XLPE cable shelf depreciation.
Background technology
Crosslinked polyethylene (XLPE) power cable, because of advantages such as its structure are simple, load capacity strong, lay easily, operation maintenance convenience, excellent insulation performance, production technology are simple, is widely used in electric system.Along with the widespread use of XLPE cable circuit, intermediate head is as the important component part of power cable, and use amount also increases thereupon.But cable intermediate joint is also the multiple position of transmission line of electricity accident, and its reliability directly affects the safety of electric power system simultaneously.Cable intermediate joint is due to many factors such as poor material, coarse manufacture craft, on-the-spot installation lack of standardization and electricity, heat, mechanical stresses, and can form latency insulation defect, the operation for electrical network brings potential potential safety hazard.Operating experience and research all show: all kinds of typical defects that the cable splice design phase exists can produce shelf depreciation mostly, and therefore the Partial Discharge Detection of cable splice has very important significance for the normal operation of high-tension cable and failure prediction.
And at present along with the quick increase of offshore wind farm installed capacity and the development of HVDC Transmission Technology, direct current cables rely on its loss low, be easy to carry out the advantages such as power adjustments, demand rapidly improves.Particularly in recent years based on the development of voltage source converter VSC (voltagesourceconverter) technology, greatly facilitate with the development of crosslinked polyethylene (XLPE) the flexible direct current cable that is major insulation material, compared to oil paper cable, XLPE direct current cables has environmental friendliness more, and the advantages such as simple are laid in manufacture.Usual direct current cables circuit is long, electric pressure is high, gigantic project, and importance is high, therefore detects its duty, guarantees that it is necessary in normal duty.Consider the method for operation that direct current cables is different from ac cable, directly apply mechanically ac cable detection means may and improper, at present for direct current cables detect analysis means still very deficient.
The important means that Partial Discharge Detection detects as ac cable, can as the important means of reflection dielectric level.For XLPE direct current cables, under certain voltage, may shelf depreciation be produced equally when its cable major insulation or annex generation defect, therefore Partial Discharge Detection be carried out to direct current cables system and can find its defect that may exist equally.And Partial Discharge Detection, DC partial discharge with exchange local discharge characteristic and have remarkable difference, be compared to interchange shelf depreciation, the repetition rate of DC partial discharge is lower, and only have electric discharge amplitude and inter-spike intervals, there is no the concept at discharge phase angle, therefore commonly use in the middle of interchange Analysis of Partial Discharge
-q-n etc. just cannot be applied to DC partial discharge with the analysis mode of phase angular dependence (-dance).Need to analyze by special means for DC partial discharge, this respect is still relatively blank at present.
For high-voltage alternating cable electric field distribute in a insulating layer depend on electric cable capacitance electric field geometry distribution, and suppose specific inductive capacity be one not temperature variant constant time just can easily obtain, thus add load and run be heated to operating temperature in it is constant all the time, although actual conditions specific inductive capacity can change a lot, its impact is almost negligible.
Electric field in the insulation of high-voltage alternating cable can be expressed as usually:
Wherein: E
aC(r)=radius be r place AC field distribution (kV/mm or MV/m)
U
0the design voltage of=cable, i.e. voltage (kV) on dielectric; Namely phase voltage is represented in interchange field
R=radius distance (mm)
R
i=cable insulation inside radius (mm)
R
0=cable insulation external radius (mm)
For high voltage direct current cable, its Electric Field Distribution changes with temperature and time, this is because direct current cables Electric Field Distribution is determined by this resistance under steady state conditions, namely the resistivity insulated is decided by, and dielectric resistivity depends on temperature and electric field intensity conversely, only when non-loading cable inside does not have thermograde yet, the Electric Field Distribution situation of direct current cables is substantially identical with interchange.
Electric field in high-voltage DC cable insulating can be expressed as usually:
Wherein
Wherein:
The temperature coefficient (1/K or 1/ DEG C) of a=conductivity
The stress coefficient (mm/kV or m/MV) of b=conductivity
Wherein:
W
cjoule heat loss (w/m) in=conductor
λ
tthe thermal conductivity of=insulation
The change of discharge position place local field strength mainly can be reflected in the change of electric discharge repetition rate, and affect due to the thermal effect of electric field, the change of electric field can cause again the change of temperature conversely, thus causes the coupled relation of electric field and temperature, produces complicated impact for electric discharge.
Summary of the invention
The object of the invention is to solve above-mentioned the problems of the prior art, a kind of test and assessment device and method to direct current XLPE cable shelf depreciation is provided.
To achieve these goals, the present invention is achieved by the following technical solutions:
A kind of DC partial discharge measurement mechanism, comprises tested cable and the DC partial discharge pick-up unit for obtaining local discharge signal; The two ends of tested cable are connected with high direct voltage output unit and current output device; Tested cable is laid with temperature-detecting device.
Described high direct voltage output unit adopts power frequency testing transformer that industrial frequency AC 220V is risen to power frequency high voltage U
t, carry out half-wave rectification through silicon stack D, then be connected in series current-limiting resistance R and charge to filter capacitor C, finally output on tested cable.
Described temperature-detecting device adopts the PT100 thermopair be laid on tested cable surface and cable accessory.
Described current output device adopts punching transformer, and the junction of punching transformer and tested cable is provided with the grading shield for preventing corona; Punching transformer is also connected with pressure regulator.
Described DC partial discharge pick-up unit comprises detection impedance measurement loop, HF current transformer and sonac; Detect the regulation in impedance measurement loop employing IEC60270 standard, HF current transformer is connected on the ground wire of tested cable, and tested cable splice is close to by sonac.
To a test and assessment method for direct current XLPE cable shelf depreciation, comprise the following steps:
1) when current output device is closed, utilize high direct voltage output unit to pressurize to tested cable, boost to setting trial voltage, record device for detecting temperature displays temperature;
2) local discharge signal is coupled by DC partial discharge pick-up unit;
3) to the local discharge signal denoising after coupling;
4) extract the electric discharge amplitude Q in local discharge signal under time domain, launch with the functional form of function of time t, the Q-t figure formed for showing electric discharge amplitude rule over time carries out DC partial discharge analysis;
5) three-dimensional spectrum be applicable in DC partial discharge analysis situation is set up;
6) by carrying out DC partial discharge to the tested cable of multiple different defect, and the different H obtained (Q, Δ t) three-dimensional spectrum and corresponding electric discharge type being preserved, setting up fingerprint base; The H obtained (Q, Δ t) image and electric discharge image are contrasted, realizes the judgement of the defect type to DC partial discharge;
7) to step 3) local discharge signal that obtains carries out fast Fourier change, under frequency domain, analyzing the distribution of local discharge signal within the scope of different frequency range, judging by analyzing the defect type of peak frequencies to actual discharge or noise, internal discharge or corona discharge and generation electric discharge;
8) high direct voltage output unit is regulated, reduce the voltage to 0kV, firing current output unit punching transformer, current analog banded cable is regulated to carry situation, observe cable and attachment surface temperature thereof in device for detecting temperature, its surface temperature is made to be elevated to 70 DEG C or more, with the situation under dummycable heavy-duty service condition;
9) until temperature reach stable after, recycling high direct voltage output unit pressurizes to tested sample of cable, after boosting to setting trial voltage, record device for detecting temperature displays temperature;
10) step 2 is repeated) ~ step 7) detect analytic process, complete measurement, measured rear close current output unit and high direct voltage output unit, tested sample is left standstill and temperature is reduced and carries out effectively electric discharge 24 hours.
Described step 2) in, to sensors coupled to local discharge signal amplify and filtering process, then perform step 3).
Described step 3) in, denoising is caught by pulse signals, filtered by the signal contrary with applying DC voltage polarity.
Described step 5) in, the concrete grammar that foundation is applicable to the three-dimensional spectrum in DC partial discharge analysis situation is as follows:
Phase angle is replaced with discharge pulse in DC partial discharge process and the time interval Δ t between its preorder discharge pulse
, set up different discharge time and account for relation H (Q, Δ t) between the number percent of total discharge time and power-discharging density H, the amplitude Q that wherein discharges extracts in the middle of Q-t figure draws; For the extraction of adjacent pulse time interval Δ t, according to discharge threshold Q
minsetting, be effective discharge pulse to exceed the pulse of discharge threshold, record each discharge pulse at Q-t respective coordinates parameter (Q
i, t
i), wherein Q
i>Q
min, and Δ t=t
i-t
i-1obtain Δ t.
Compared with prior art, the present invention has following beneficial effect:
The present invention, according to DC partial discharge and the difference exchanging shelf depreciation, adopts the means being applicable to exchange Partial Discharge Detection and analysis, has filled up the blank of DC partial discharge examination and analysb method.The feature low according to DC partial discharge repetition rate, 30-60 minute long-time measurement of partial discharge is proposed, and according to the concept of the corresponding phase angle of DC partial discharge no pulse, thus cause not being suitable for DC partial discharge analysis with phase angle correlation analysis means in the middle of interchange Analysis of Partial Discharge method, thus adopt based on Q-t figure, the research mode that N-t, N-Q figure is auxiliary, replaces phase angle to be formed with time interval Δ t between two adjacent discharge pulses simultaneously and is applicable to DC partial discharge analyzing three-dimensional spectrogram.Simultaneously especially unipolar according to DC partial discharge signal pulse, in the middle of denoising, opposite polarity pulse is removed to ensure the accuracy measured as interference.The present invention considers the impact of temperature for shelf depreciation, the change of electric discharge repetition rate is directly reacted on because temperature has appreciable impact for the Electric Field Distribution under direct current, the measurement result of carrying out measurement of partial discharge under therefore adopting dummycable at normal temperatures is unloaded or off-line state to combine the comprehensive mode analyzed be with the measurement result of carrying out measurement of partial discharge under year state with utilizing current output device dummycable, cable insulation situation is carried out to the assessment of more Comprehensive.
Accompanying drawing explanation
Fig. 1 is test schematic of the present invention;
Fig. 2 is experiment process figure of the present invention;
Fig. 3 is DC partial discharge analytical approach process flow diagram of the present invention;
Fig. 4 is the ground unrest waveform of the embodiment of the present invention;
Fig. 5 is the corresponding frequency domain distribution figure of ground unrest waveform of the embodiment of the present invention;
Fig. 6 is the pulse waveform of the impulse source B of the embodiment of the present invention;
The corresponding frequency domain distribution figure of pulse waveform of the impulse source B that Fig. 7 is the embodiment of the present invention;
Fig. 8 is the Q-t spectrogram of the embodiment of the present invention;
Fig. 9 be the embodiment of the present invention N-t wherein N be set to discharge time in 1min;
Figure 10 is N-Q spectrogram of the present invention, and wherein N is set to discharge time in 1min;
Figure 11 is Q-Δ t spectrogram of the present invention.
Embodiment
Below in conjunction with accompanying drawing, the present invention will be further described in detail:
See Fig. 1, the invention provides the examination and analysb method of a kind of shelf depreciation for XLPE direct current cables in conjunction with temperature, compare interchange local discharge signal due to DC partial discharge signal and there is the significantly differences such as electric discharge repetition rate is low, the corresponding phase angle of discharge off pulse, therefore the long-time DC partial discharge of 30-60min is adopted to measure in the present invention, another employing with Q-t figure be main combination be applicable to DC partial discharge analyze the common H of novel three-dimensional (Q, Δ t) carry out pattern-recognition.Due under direct current, the Electric Field Distribution in insulation depends on the distribution of resistivity, and resistance can vary with temperature generation significant change, thus affects the distribution of this place's electric field, and the change of discharge position place local field strength mainly can be reflected in the change of electric discharge repetition rate.And affect due to the thermal effect of electric field, the change of electric field can cause again the change of temperature conversely, thus causes the coupled relation of electric field and temperature, produces complicated impact for electric discharge.The present invention considers the impact of temperature variation for electric discharge, temperature is included in comprehensive examination and evaluation scope.
Circuit arrangement of the present invention:
(1) high direct voltage output unit: the unavailable high voltage direct current generator of direct current compression system, because it can introduce the interference of obvious impulse type, and close with partial discharge pulse band limits, thus the standard causing measurement result signal to noise ratio (S/N ratio) cannot reach 2:1 even floods discharge pulse.The present invention adopts half-wave rectification to produce high direct voltage, first uses power frequency testing transformer that industrial frequency AC 220V is risen to power frequency high voltage U
t, through withstand voltage be at least 4.3U
tthe silicon stack of (be voltage breakdown 2/3 according to design voltage nargin) carries out half-wave rectification, and serial connection current-limiting resistance R charges to filter capacitor C, and filter capacitor C is withstand voltage to be at least
wherein silicon stack through-current capability is determined by silicon stack model, and the present invention recommends to adopt 3A.Current-limiting resistance and filtering capacitance are required by ripple according to correlation technique in high-voltage test techniques and trial voltage, electric current determine, wherein according to standard GB/T/T:16927.1 related content, DC high potential test equipment ripple factor should be less than 3%.Parallel resistance voltage divider after high voltage direct current presser unit, wherein resitstance voltage divider display is actual applies DC voltage numerical value.
(2) current output device: punching transformer is mainly cable and joint bearing high-tensionly provides big current, with dummycable operating load simultaneously.Cable carries in process at band, and because heating effect of current causes temperature to raise, analog temperature affects.Punching transformer and cable junction install grading shield additional and occur to prevent corona.
(3) device for detecting temperature: thermopair PT100 is laid in cable surface and cable accessory, carries out temperature monitoring to cable surface and its annex.
(4) DC partial discharge measurement mechanism: DC partial discharge detects the mode obtaining local discharge signal and is divided in the electrical measuring method and collection shelf depreciation process of collecting and producing electric signal in shelf depreciation process the non-electrical measuring method produced as the non-electrical signal such as sound, light.The present invention is applicable to electrical measuring method and sound detection.For electrical measuring method, the pulse current method (namely detect impedance and carry out local discharge signal detection), the HF current transformer (HFCT) that are applicable to IEC60270 recommendation are collected for the electric signal obtained in shelf depreciation process, and sound detection is applicable to use piezoelectric as sensor, mechanical oscillation signal is converted to electric signal.Detect in impedance measurement loop reference IEC60270 standard and specify, HF current transformer installation site is connected on ground wire, tested cable splice (as tested cable is furnished with the annex such as cable splice or terminal, being preferably placed with on annex) is close to by sonac.
The concrete test and assessment method of the present invention comprises the following steps:
(1) first current output device punching transformer cuts out namely not in output current situation, utilizes high direct voltage output unit to pressurize to tested sample of cable, boosts to agreement trial voltage, record device for detecting temperature displays temperature.
(2) local discharge signal is coupled by DC partial discharge measurement mechanism.For the shelf depreciation under DC voltage, because repetition rate is lower, Measuring Time needs to reach 30-60 minute.
(3) for improving measuring accuracy, signal transacting link can be added after sensor, by sensors coupled to signal carry out necessary amplification and filtration.As adopted electrical measuring method, can will access wave filter under the stronger environment of environment electromagnetics interference, by sensors coupled to signal carry out filtering, filter parameter should be selected according to actual noise environment.As discharge signal is then more weak, after filtering, add amplifier, signal is amplified, can select for site test amplifier band corresponding narrower, recommend frequency band at 1MHz-500MHz, use in laboratory and then use wide-band amplifier.Measure for employing ultrasonic method, after sensor, connect prime amplifier, enlargement factor is at more than 20dB, and frequency of operation is recommended in 10kHz-2000kHz.
(4) for in-site measurement, noise is the key factor that restriction Partial Discharge Detection uses, denoising is very crucial, in the middle of DC partial discharge is measured, apply DC voltage be unipolarity therefore local discharge signal also for unipolarity, for DC partial discharge signal based on its unipolar feature, by catching for pulse signal, the signal contrary with applying DC voltage polarity is considered as noise signal filtered, thus reduces the impact of noise.
(5) by sensors coupled to signal, obtain effective discharge signal through signal transacting and denoising.Compare interchange shelf depreciation due to DC partial discharge and lack phase angle
concept, therefore exchange in the middle of Analysis of Partial Discharge and phase angle
correlation analysis means all inapplicable in the middle of direct current, need re-establish the analysis means being applicable to DC partial discharge.For the analytical approach of DC partial discharge, the present invention be with under time domain for local discharge signal in the amplitude Q that discharges extract, launch with the functional form of function of time t, form Q-t figure as main analysis means, performance electric discharge amplitude rule over time.First threshold value should be set in the middle of actual measurement, threshold value is arranged on background noise level, and ensure to be no more than simultaneously electric discharge amplitude 1/2 to ensure that signal to noise ratio (S/N ratio) reaches 2:1, exceed threshold value is set be then judged as effective discharge pulse.Set up relation between electric discharge repetition rate N in one minute and test period t in addition, form N-t figure, performance electric discharge repetition rate Changing Pattern in time.In the middle of DC partial discharge detects, average minute clock electric discharge repetition rate is not less than once i.e. N >=1, just produces effective partial discharge phenomenon, just makes voltage during sample generation N=1 then be regarded as the DC partial discharge starting potential of sample.For Q-t figure relation, as under certain trial voltage, discharge capacity Q very large and at the trial in keep stable or electric discharge repetition rate N very large and keep stable within the time, or to increase in time, Q, N are obvious ascendant trend, should pay close attention to for tested sample insulation status.
(6) due to direct current cables system, the reason that may produce electric discharge is a lot, as factors such as major insulation scuffing, stress cone dislocation, discharge characteristic due to different electric discharge type has remarkable difference, and its development trend also has difference, and therefore corresponding countermeasure should with reference to different defect types.Exchange in the middle of Partial Discharge Detection and be usually used in the PRPD spectrogram of pattern-recognition is carried out owing to lacking phase angle under direct current for different electric discharge type
concept and cannot using.The present invention's foundation is applicable to the three-dimensional spectrum in DC partial discharge analysis situation.Phase angle is replaced with discharge pulse in DC partial discharge process and the time interval Δ t between its preorder discharge pulse
build on different discharge time and account for relation H (Q, Δ t) between the number percent of total discharge time and power-discharging density H, the amplitude Q that wherein discharges extracts in the middle of step (5) Q-t schemes to draw, and for the extraction of adjacent pulse time interval Δ t, according to discharge threshold Q
minsetting be effective discharge pulse to exceed the pulse of discharge threshold, record each discharge pulse at Q-t respective coordinates parameter (Q
i, t
i), wherein Q
i>Q
min, and Δ t=t
i-t
i-1obtain Δ t.
(7) by carrying out DC partial discharge for the test product of a large amount of different defect, and the different H obtained (Q, Δ t) three-dimensional spectrum and corresponding electric discharge type being preserved, setting up fingerprint base.For the H obtained (Q, Δ t) image, by carrying out contrasting with electric discharge image thus carry out judgement and pattern-recognition for defect type.
(8) the present invention adopts the discharge signal through signal transacting and denoising obtained for step (5) to carry out fast Fourier change FFT in addition, analyzes the distribution of discharge signal within the scope of different frequency range under frequency domain.The waveform component of the discharge waveform different frequency of recording different types is different, therefore can by the analysis for peak frequencies etc. for actual discharge or noise, internal discharge or corona discharge and produce the defect type discharged and judge.
(9) high direct voltage output unit is regulated, reduce the voltage to 0kV, firing current output unit punching transformer, current analog banded cable is regulated to carry situation, observe cable and attachment surface temperature thereof in device for detecting temperature, make its surface temperature be elevated to 70 DEG C or more with the situation under dummycable heavy-duty service condition.
(10) until temperature reach stable after, recycling high direct voltage output unit pressurizes to tested sample of cable, boosts to agreement trial voltage, record device for detecting temperature displays temperature.After come again step (2)-step (8) and detect analytic process, complete measurement, measured rear close current output unit and high direct voltage output unit, tested sample is left standstill and temperature is reduced and carries out effective electric discharge 24 hours.
Above content is only and technological thought of the present invention is described; protection scope of the present invention can not be limited with this; every technological thought proposed according to the present invention, any change that technical scheme basis is done, within the protection domain all falling into claims of the present invention.
Claims (9)
1. a DC partial discharge measurement mechanism, is characterized in that: comprise tested cable and the DC partial discharge pick-up unit for obtaining local discharge signal; The two ends of tested cable are connected with high direct voltage output unit and current output device; Tested cable is laid with temperature-detecting device.
2. DC partial discharge measurement mechanism according to claim 1, is characterized in that: described high direct voltage output unit adopts power frequency testing transformer that industrial frequency AC 220V is risen to power frequency high voltage U
t, carry out half-wave rectification through silicon stack D, then be connected in series current-limiting resistance R and charge to filter capacitor C, finally output on tested cable.
3. DC partial discharge measurement mechanism according to claim 1, is characterized in that: described temperature-detecting device adopts the PT100 thermopair be laid on tested cable surface and cable accessory.
4. DC partial discharge measurement mechanism according to claim 1, is characterized in that: described current output device adopts punching transformer, and the junction of punching transformer and tested cable is provided with the grading shield for preventing corona; Punching transformer is also connected with pressure regulator.
5. DC partial discharge measurement mechanism according to claim 1, is characterized in that: described DC partial discharge pick-up unit comprises detection impedance measurement loop, HF current transformer and sonac; Detect the regulation in impedance measurement loop employing IEC60270 standard, HF current transformer is connected on the ground wire of tested cable, and tested cable splice is close to by sonac.
6. adopt the test and assessment method to direct current XLPE cable shelf depreciation of device described in claim 1-5 any one, it is characterized in that, comprise the following steps:
1) when current output device is closed, utilize high direct voltage output unit to pressurize to tested cable, boost to setting trial voltage, record device for detecting temperature displays temperature;
2) local discharge signal is coupled by DC partial discharge pick-up unit;
3) to the local discharge signal denoising after coupling;
4) extract the electric discharge amplitude Q in local discharge signal under time domain, launch with the functional form of function of time t, the Q-t figure formed for showing electric discharge amplitude rule over time carries out DC partial discharge analysis;
5) three-dimensional spectrum be applicable in DC partial discharge analysis situation is set up;
6) by carrying out DC partial discharge to the tested cable of multiple different defect, and the different H obtained (Q, Δ t) three-dimensional spectrum and corresponding electric discharge type being preserved, setting up fingerprint base; The H obtained (Q, Δ t) image and electric discharge image are contrasted, realizes the judgement of the defect type to DC partial discharge;
7) to step 3) local discharge signal that obtains carries out fast Fourier change, under frequency domain, analyzing the distribution of local discharge signal within the scope of different frequency range, judging by analyzing the defect type of peak frequencies to actual discharge or noise, internal discharge or corona discharge and generation electric discharge;
8) high direct voltage output unit is regulated, reduce the voltage to 0kV, firing current output unit punching transformer, current analog banded cable is regulated to carry situation, observe cable and attachment surface temperature thereof in device for detecting temperature, its surface temperature is made to be elevated to 70 DEG C or more, with the situation under dummycable heavy-duty service condition;
9) until temperature reach stable after, recycling high direct voltage output unit pressurizes to tested sample of cable, after boosting to setting trial voltage, record device for detecting temperature displays temperature;
10) step 2 is repeated) ~ step 7) detect analytic process, complete measurement, measured rear close current output unit and high direct voltage output unit, tested sample is left standstill and temperature is reduced and carries out effectively electric discharge 24 hours.
7. the test and assessment method to direct current XLPE cable shelf depreciation according to claim 6, is characterized in that: described step 2) in, to sensors coupled to local discharge signal amplify and filtering process, then perform step 3).
8. the test and assessment method to direct current XLPE cable shelf depreciation according to claim 6 or 7, it is characterized in that: described step 3) in, denoising is caught by pulse signals, filtered by the signal contrary with applying DC voltage polarity.
9. the test and assessment method to direct current XLPE cable shelf depreciation according to claim 6, is characterized in that, described step 5) in, the concrete grammar that foundation is applicable to the three-dimensional spectrum in DC partial discharge analysis situation is as follows:
Phase angle is replaced with discharge pulse in DC partial discharge process and the time interval Δ t between its preorder discharge pulse
set up different discharge time and account for relation H (Q, Δ t) between the number percent of total discharge time and power-discharging density H, the amplitude Q that wherein discharges extracts in the middle of Q-t figure draws; For the extraction of adjacent pulse time interval Δ t, according to discharge threshold Q
minsetting, be effective discharge pulse to exceed the pulse of discharge threshold, record each discharge pulse at Q-t respective coordinates parameter (Q
i, t
i), wherein Q
i>Q
min, and Δ t=t
i-t
i-1obtain Δ t.
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| CN201510053432.3A CN104714155B (en) | 2015-02-02 | 2015-02-02 | A kind of detection to direct current XLPE cable shelf depreciation and apparatus for evaluating and method |
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| CN201510053432.3A CN104714155B (en) | 2015-02-02 | 2015-02-02 | A kind of detection to direct current XLPE cable shelf depreciation and apparatus for evaluating and method |
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| CN104714155B CN104714155B (en) | 2017-12-15 |
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| CN201510053432.3A Active CN104714155B (en) | 2015-02-02 | 2015-02-02 | A kind of detection to direct current XLPE cable shelf depreciation and apparatus for evaluating and method |
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| CN105203936A (en) * | 2015-10-26 | 2015-12-30 | 云南电网有限责任公司电力科学研究院 | Method for determining power cable partial discharge defect type based on spectral analysis |
| CN105548849A (en) * | 2016-02-19 | 2016-05-04 | 西安交通大学 | Local discharge testing circuit and method for high-voltage direct current cable |
| CN105911443A (en) * | 2016-07-06 | 2016-08-31 | 三峡大学 | Online measurement system for partial discharge of cable middle joint based on clamp-shaped coaxial capacitor |
| CN106066452A (en) * | 2016-08-03 | 2016-11-02 | 国网浙江省电力公司电力科学研究院 | Quantity of state detecting system under a kind of high tension cable typical defect |
| 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 |
| CN106405357A (en) * | 2016-12-15 | 2017-02-15 | 中国南方电网有限责任公司超高压输电公司贵阳局 | Direct-current partial discharge testing system and method for extra-high-voltage power transmission and transformation equipment |
| CN107064763A (en) * | 2017-05-29 | 2017-08-18 | 西南交通大学 | Extreme delta is got off the local discharge test System and method for of download cable terminal |
| CN107907805A (en) * | 2017-12-11 | 2018-04-13 | 西南交通大学 | A kind of vehicle-mounted cable low temperature shelf depreciation start-phase evaluation method of power-frequency voltage negative half period |
| 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 |
| CN108254662A (en) * | 2018-03-15 | 2018-07-06 | 广东电网有限责任公司东莞供电局 | Shelf depreciation simulator |
| CN105717428B (en) * | 2016-02-19 | 2018-09-04 | 西安交通大学 | A kind of cable partial discharge live correction method based on HFCT |
| 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 |
| CN108983050A (en) * | 2018-07-05 | 2018-12-11 | 国网浙江省电力有限公司舟山供电公司 | A method of load measuring direct current cables shelf depreciation is superimposed using DC voltage |
| CN109164358A (en) * | 2018-08-22 | 2019-01-08 | 西南交通大学 | A kind of cable integral insulation dampness failure simulation method |
| CN109212392A (en) * | 2018-09-25 | 2019-01-15 | 上海交通大学 | Recognition methods, system and the Caffe convolutional neural networks of direct current cables shelf depreciation defect failure |
| 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 |
| CN109643896A (en) * | 2016-05-17 | 2019-04-16 | 通用电气技术有限公司 | The control of high-voltage direct-current system |
| CN110196382A (en) * | 2019-07-05 | 2019-09-03 | 杭州西湖电子研究所 | A kind of no check frequency oscillation wave partial discharge detection device |
| 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 |
| CN111025093A (en) * | 2019-11-19 | 2020-04-17 | 云南电网有限责任公司临沧供电局 | XLPE cable insulation life estimation method based on double-end balance factor |
| CN111579951A (en) * | 2020-05-29 | 2020-08-25 | 全球能源互联网欧洲研究院 | Direct-current cable discharge detection device and detection method |
| CN113253064A (en) * | 2021-04-12 | 2021-08-13 | 广东电网有限责任公司广州供电局 | Method and device for detecting partial discharge of cable |
| CN113311291A (en) * | 2021-05-28 | 2021-08-27 | 国网江苏省电力有限公司无锡供电分公司 | Partial discharge detection sensitivity testing device and method for long-section high-voltage cable |
| CN113884837A (en) * | 2021-11-03 | 2022-01-04 | 国网河南省电力公司驻马店供电公司 | Online monitoring and analyzing system and method for partial discharge of cable |
| CN114019329A (en) * | 2021-11-08 | 2022-02-08 | 国网山东省电力公司莱芜供电公司 | XLPE cable insulation early deterioration multidimensional evaluation system and method based on machine learning |
| CN114779027A (en) * | 2022-05-18 | 2022-07-22 | 四川大学 | PDIV testing device and method capable of achieving intelligent temperature rise |
| CN118091407A (en) * | 2024-04-23 | 2024-05-28 | 荣成市泰锞机械有限公司 | Method and device for testing insulation performance of engine stator |
| CN118091407B (en) * | 2024-04-23 | 2024-07-05 | 荣成市泰锞机械有限公司 | Method and device for testing insulation performance of engine stator |
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| CN105203936A (en) * | 2015-10-26 | 2015-12-30 | 云南电网有限责任公司电力科学研究院 | Method for determining power cable partial discharge defect type based on spectral analysis |
| CN105548849A (en) * | 2016-02-19 | 2016-05-04 | 西安交通大学 | Local discharge testing circuit and method for high-voltage direct current cable |
| CN105717428B (en) * | 2016-02-19 | 2018-09-04 | 西安交通大学 | A kind of cable partial discharge live correction method based on HFCT |
| CN109643896A (en) * | 2016-05-17 | 2019-04-16 | 通用电气技术有限公司 | The control of high-voltage direct-current system |
| CN109643896B (en) * | 2016-05-17 | 2022-07-29 | 通用电气技术有限公司 | Control of high voltage DC systems |
| CN105911443A (en) * | 2016-07-06 | 2016-08-31 | 三峡大学 | Online measurement system for partial discharge of cable middle joint based on clamp-shaped coaxial capacitor |
| CN106066452A (en) * | 2016-08-03 | 2016-11-02 | 国网浙江省电力公司电力科学研究院 | Quantity of state detecting system under a kind of high tension cable typical defect |
| 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 |
| CN106405357A (en) * | 2016-12-15 | 2017-02-15 | 中国南方电网有限责任公司超高压输电公司贵阳局 | Direct-current partial discharge testing system and method for extra-high-voltage power transmission and transformation equipment |
| CN106405357B (en) * | 2016-12-15 | 2019-06-25 | 中国南方电网有限责任公司超高压输电公司贵阳局 | A kind of extra-high voltage electric transmission and transformation equipment DC partial discharge test macro and test method |
| CN107064763A (en) * | 2017-05-29 | 2017-08-18 | 西南交通大学 | Extreme delta is got off the local discharge test System and method for of download cable terminal |
| CN107064763B (en) * | 2017-05-29 | 2018-11-30 | 西南交通大学 | Extreme delta is got off download cable terminal part discharge test System and method for |
| CN107907805A (en) * | 2017-12-11 | 2018-04-13 | 西南交通大学 | A kind of vehicle-mounted cable low temperature shelf depreciation start-phase evaluation method of power-frequency voltage negative half period |
| CN107907805B (en) * | 2017-12-11 | 2019-09-06 | 西南交通大学 | The vehicle-mounted cable low temperature shelf depreciation start-phase evaluation method of power-frequency voltage negative half period |
| 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 |
| CN108254662A (en) * | 2018-03-15 | 2018-07-06 | 广东电网有限责任公司东莞供电局 | Shelf depreciation simulator |
| 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 |
| CN108983050A (en) * | 2018-07-05 | 2018-12-11 | 国网浙江省电力有限公司舟山供电公司 | A method of load measuring direct current cables shelf depreciation is superimposed using DC voltage |
| CN109164358A (en) * | 2018-08-22 | 2019-01-08 | 西南交通大学 | A kind of cable integral insulation dampness failure simulation method |
| CN109212392A (en) * | 2018-09-25 | 2019-01-15 | 上海交通大学 | Recognition methods, system and the Caffe convolutional neural networks of direct current cables shelf depreciation defect failure |
| 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 |
| CN110196382A (en) * | 2019-07-05 | 2019-09-03 | 杭州西湖电子研究所 | A kind of no check frequency oscillation wave partial discharge detection device |
| CN110196382B (en) * | 2019-07-05 | 2023-12-22 | 杭州西湖电子研究所 | No detection blind area oscillatory wave partial discharge detection device |
| CN110988612B (en) * | 2019-11-08 | 2021-07-20 | 广东电网有限责任公司 | Cable head insulation performance online monitoring system and method |
| 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 |
| CN111025093A (en) * | 2019-11-19 | 2020-04-17 | 云南电网有限责任公司临沧供电局 | XLPE cable insulation life estimation method based on double-end balance factor |
| CN111579951A (en) * | 2020-05-29 | 2020-08-25 | 全球能源互联网欧洲研究院 | Direct-current cable discharge detection device and detection method |
| CN113253064A (en) * | 2021-04-12 | 2021-08-13 | 广东电网有限责任公司广州供电局 | Method and device for detecting partial discharge of cable |
| CN113311291A (en) * | 2021-05-28 | 2021-08-27 | 国网江苏省电力有限公司无锡供电分公司 | Partial discharge detection sensitivity testing device and method for long-section high-voltage cable |
| CN113884837A (en) * | 2021-11-03 | 2022-01-04 | 国网河南省电力公司驻马店供电公司 | Online monitoring and analyzing system and method for partial discharge of cable |
| CN113884837B (en) * | 2021-11-03 | 2023-07-28 | 国网河南省电力公司驻马店供电公司 | Cable partial discharge online monitoring and analyzing system and analyzing method |
| CN114019329A (en) * | 2021-11-08 | 2022-02-08 | 国网山东省电力公司莱芜供电公司 | XLPE cable insulation early deterioration multidimensional evaluation system and method based on machine learning |
| CN114779027A (en) * | 2022-05-18 | 2022-07-22 | 四川大学 | PDIV testing device and method capable of achieving intelligent temperature rise |
| CN118091407A (en) * | 2024-04-23 | 2024-05-28 | 荣成市泰锞机械有限公司 | Method and device for testing insulation performance of engine stator |
| CN118091407B (en) * | 2024-04-23 | 2024-07-05 | 荣成市泰锞机械有限公司 | Method and device for testing insulation performance of engine stator |
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