CN104730436A - Cable aging estimation method combining step-by-step withstand voltage method and isothermal relaxation current method - Google Patents
Cable aging estimation method combining step-by-step withstand voltage method and isothermal relaxation current method Download PDFInfo
- Publication number
- CN104730436A CN104730436A CN201510113947.8A CN201510113947A CN104730436A CN 104730436 A CN104730436 A CN 104730436A CN 201510113947 A CN201510113947 A CN 201510113947A CN 104730436 A CN104730436 A CN 104730436A
- Authority
- CN
- China
- Prior art keywords
- cable
- assessed
- voltage
- aging
- current method
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Testing Relating To Insulation (AREA)
Abstract
The invention discloses a cable aging estimation method combining a step-by-step withstand voltage method and an isothermal relaxation current method. The cable aging estimation method includes the following steps of step-by-step withstand voltage method testing and isothermal relaxation current method testing. According to the cable aging estimation method, on one hand, a result obtained through the isothermal relaxation current method is used as a tendency judgment and used for judging a rough cable aging degree, and on the other hand, a result obtained through the withstand voltage method is used as a concrete judgment, and then the remaining service life of a cable can be inferred. In other words, the result obtained through the isothermal relaxation current method is the tendency judgment, the result obtained through the withstand voltage method is the concrete judgment, and hereby the cable aging situation can be estimated by combining a destructive test and a nondestructive test to determine whether the cable needs to be replaced or not. Accordingly, one-sided reflection of a single method on an estimation result is avoided, the result can be higher in reference value, and the cable aging estimation method can have guidance significance on power grid transformation and operation, maintenance and detection of the cable.
Description
Technical field
The present invention relates to crosslinking polyethylene-insulated cable insulation Performance Detection technical field, particularly relate to the crosslinking polyethylene-insulated cable insulation performance method for quick of a kind of combination resistance to platen press and isothermal relaxation current method step by step.
Background technology
Since last century the eighties, domestic and international cable technology fast development, traditional oil-filled cable is substituted by the XLPE cable that three-layer co-extruded production technology manufactures gradually.Compared with the former, the latter has the premium properties such as and mechanical electric performance simple without the need to fuel feeding, fire prevention, installation and maintenance be good, and range of application expands gradually.For domestic, XLPE cable in Shanghai, Beijing, the big city such as Guangzhou be used widely.Fully realize the insulation characterisitic of XLPE cable, find and prevent some defect of existence in insulation timely and effectively, the safe operation tool of support equipment and even system is of great significance.
Because on-the-spot high power laboratory power supply is difficult to obtain, traditional cable often adopts DC voltage withstand test, assesses insulation effect by measuring leakage current.But under the effect respectively of alternating voltage and DC voltage, the Electric Field Distribution of XLPE cable insulation is different.The former depends primarily on the specific inductive capacity of each medium, and latter depends primarily on the resistivity of material, the insulation weak link under both differences in principle cause DC test to be difficult to find alternating voltage.
In addition, DC voltage withstand test has build-up effect to insulation, and it is aging to accelerate cable, shortens cable serviceable life.Therefore, XLPE cable does not adopt DC voltage withstand test.
Withstand voltage test is close to cable practical operation situation step by step, and withstand voltage is lower, more can reflect cable insulation situation and find insulation defect.Therefore withstand voltage test is comparatively effective to XLPE cable Insulation monitoring step by step.
Isothermal relaxation current method utilizes the isothermal relaxation electric current of test gained to judge cable aging performance, is a kind of nondestructive research method.And the history run of cable can't affect its Evaluated effect, utilize cable testing result to lay the time limit just can obtain cable residual life without the need to combining, therefore the method obtains industry and generally applies.
Summary of the invention
The object of the invention is to overcome the shortcoming of prior art and deficiency, the cable aging assessment of a kind of combination resistance to platen press and isothermal relaxation current method is step by step provided, the test of the method decohesion and non-destructive testing (NDT) are assessed cable aging performance, avoid the unilateral reflection of single method to assessment result, make Aging Assessment result have more reference value.
Object of the present invention is achieved through the following technical solutions:
A cable aging assessment for combination resistance to platen press and isothermal relaxation current method step by step, comprises the following steps:
Resistance to platen press test procedure step by step, this step, by adopting flash test step by step on sample of cable to be assessed, according to the difference boosting parameter of regulation, applies power-frequency voltage step by step, obtain and record breakdown time of described sample of cable to be assessed, then calculating the residual life of described cable to be assessed;
Isothermal relaxation current method step, this step by accessing polarization high-voltage DC power supply on described sample of cable to be assessed, after the polarization time of fixed time length, utilize computer sampling record isothermal relaxation electric current, calculate the aging factor of described sample of cable to be assessed, then according to remaining voltage breakdown criterion, the relation of aging factor and remaining voltage breakdown is obtained.
Preferably, described boosting parameter comprises initial on-load voltage, step size voltage, pressing time.
Preferably, the detailed process of described resistance to platen press test procedure is step by step:
S11,2.5U0 alternating voltage is applied as described initial on-load voltage to described sample of cable to be assessed, next on-load voltage is raised using 0.25U0 step by step as described step size voltage, wherein every one-level on-load voltage continues 15min, till puncturing, record voltage breakdown and the last straw duration of described sample of cable to be assessed;
S12, utilize anti-power formula
calculate the residual life of cable to be assessed, wherein, Ei represents the on-load voltage that every one-level applies described sample of cable to be assessed, Ti represents every one-level on-load voltage to the time corresponding to described sample of cable effect to be assessed, U representative calculates voltage corresponding to described sample of cable residual life to be assessed, T represents the residual life of described sample of cable to be assessed under voltage U, and n represents the life index of described sample of cable to be assessed.
Preferably, the detailed process of described isothermal relaxation current method step is:
S21, pre-service is carried out to described sample of cable to be assessed, strip cable sample two ends external shielding layer, and reliably insulate in one end, another termination polarization high-voltage DC power supply, wherein conductor just connects, outer metallic shield ground connection, polarizes fixed time P second with high-voltage DC power supply, controlled by computing machine, the electric current and sample record record relaxes;
S22, pass through following formula
Calculate the aging factor M value of described sample of cable to be assessed, wherein, timeconstantτ
3salt in corresponding aging interface of causing and the impact of hydrated ion, timeconstantτ
2the impact at corresponding metamict crystals interface, adopts the test of isothermal relaxation current method by the amorphous polarization current I (τ produced with crystal interface
2) and the polarization current I (τ that produces due to the slaine in aging interface of causing and hydrated ion
3), and record the I (τ of not t in the same time
2), I (τ
3) value;
S23, according to remaining voltage breakdown criterion, obtain the relation of aging factor and remaining voltage breakdown.
Preferably, the historical conditions that described life index n produces according to cable to be assessed and productive capacity determine, wherein when described sample of cable to be assessed is XLPE cable, and life index n=9.
Preferably, described sample of cable to be assessed carries out keeping conductor temperature in [87 DEG C, 93 DEG C] temperature range in resistance to platen press process of the test step by step.
Preferably, described sample of cable to be assessed carries out the fixed time P=1800 second with high-voltage DC power supply polarization in isothermal relaxation current method test procedure.
Preferably, described sample of cable to be assessed carries out the relax sampling rate of electric current of sample record in isothermal relaxation current method test procedure is 2Sa/s.
Preferably, partial discharge test step, this step, by carrying out partial discharge test to described sample of cable to be assessed, contrasts according to the Apparent discharge magnitude recorded and GB/T 11017.2-2002, tentatively judges the ageing state of described sample of cable to be assessed.
The present invention has following advantage and effect relative to prior art:
1) one aspect of the present invention is by the judgement as tendency of the result that obtained by isothermal relaxation current method, in order to judge the roughly degree that cable is aging, and the result obtained by resistance to platen press is on the other hand as concrete judgement, the residual life of cable can be inferred, decohesion test and non-destructive testing (NDT) are assessed to determine whether to need to change to cable aging performance, avoid the unilateral reflection of single method to assessment result, make result have more reference value.
2) integrated use of the present invention step by step resistance to platen press and isothermal relaxation current method judge cable ageing state, life appraisal is carried out to it, for the operation of electric network reconstruction and cable, maintenance, detection, there is directive significance.
Accompanying drawing explanation
Fig. 1 is the cable aging assessment process flow diagram of a kind of combination disclosed in the present invention resistance to platen press and isothermal relaxation current method step by step;
Fig. 2 is the insulating medium cable and the equivalent circuit diagram thereof that comprise pore in embodiment;
Fig. 3 is the relation comparison diagram of shelf depreciation and voltage in embodiment;
Fig. 4 be in embodiment step by step withstand voltage test boosting curve map;
Fig. 5 is insulated cable trap level distribution schematic diagram in embodiment;
Fig. 6 is isothermal relaxation current method wiring diagram in embodiment;
Fig. 7 is isothermal relaxation current method equivalent circuit diagram in embodiment;
Fig. 8 is the aging factor value comparison diagram of different sample in embodiment;
Fig. 9 is the sample aging factor values comparison diagram of the different operation time limit in embodiment.
Embodiment
For making object of the present invention, technical scheme and advantage clearly, clearly, developing simultaneously referring to accompanying drawing, the present invention is described in more detail for embodiment.Should be appreciated that specific embodiment described herein only in order to explain the present invention, be not intended to limit the present invention.
Embodiment
The present embodiment utilizes the cable aging assessment of a kind of combination disclosed by the invention resistance to platen press and isothermal relaxation current method step by step to carry out cable Aging Assessment to cable sample.
1. cable sample is chosen
This evaluation test chooses 110kV XLPE cable, and concrete model is as follows:
1) within 1985, come into operation, 2, the cable that SUMITOMO CHEMICAL is produced.Numbering S1, S2.
2) within 1987, come into operation, 2, the cable that Furukawa Electronic produces.Numbering F1, F2.
3) within 1996, come into operation, 2, the cable that SUMITOMO CHEMICAL is produced.Numbering S3, S4.
Above 6 cable sample cross sections are 400mm2, and every root length is about 20m.
2. partial discharge test
Partial discharge test is carried out in sampling, according to the Apparent discharge magnitude recorded and GB/T 11017.2-2002 (national standard (GB) GB/T11017.1-2002 rated voltage 110kV power cable with cross-linked polyethylene insulation and annex thereof, this standard defines rated voltage 110kV (Um=126kV) for the test of hard-wired power cable with cross-linked polyethylene insulation and annex thereof and requirement) contrast, the ageing state of several cable samples is tentatively judged.This step is can optional step, shelf depreciation is a kind of commonplace method of testing in power industry, whether be used for detecting power equipment (such as cable) to lose efficacy, if shelf depreciation detected, so power equipment must be have fault or.If not there is shelf depreciation, just macroscopically, no problem, do not represent microcosmic out of question yet.Local discharge test is exactly be follow-up test is effective, if office put not by, just there is no need to carry out follow-up test.Proving that this equipment is exactly fault, may be damage to cause or cause because equipment itself is aging.
Shelf depreciation is that high pressure extrudes the most frequently used research technique of insulated cable, puts effect in the present embodiment, first, introduce the generation principle of partial discharge method below in conjunction with accompanying drawing 2 and Fig. 3 for the ease of understanding office.
If when in media interior air gap, electric field reaches the disruptive strength of gas, then gas starts electric discharge, result produces a large amount of positive and negative ion, they move formation space charge respectively towards the upper and lower wall of air gap under the effect of electric field, this space charge sets up anti-electric field makes total electric field intensity decline, thus discharge quenching.The duration of electric discharge is very short, is about 0.1 microsecond (even shorter).Therefore during electric discharge, on air gap, voltage is transition, when the leakage of voltage rise or space charge makes air gap again reach the voltage being enough to puncture, will discharge again.Because applied voltage is alternation, so this shelf depreciation is also pulse feature.
These electric discharge phenomena (process) can illustrate with accompanying drawing, C in Fig. 2
grepresent the electric capacity of air gap, C
grepresent the electric capacity (media fraction in dotted line) of medium of being in series with air gap, C
arepresent in electrode except C
b, C
gthe electric capacity of all the other media outer.Usually because void dimension is very little, C is had
a>>C
g>C
b.Ua represents the outer alternating voltage imposing on medium, Ug is the dividing potential drop on air gap, when Ug=Us (Us is the sparking voltage of air gap), bubble-discharge, produce the space charge of positive and negative ion and set up reversed electric field Δ U, as Fig. 3, total voltage decline Δ U to the Ur (Ur is residual voltage) immediately of air gap, discharge quenching.Along with the rising of applied voltage, total voltage on air gap reaches Us again, the 2nd electric discharge occurs, and adds new space charge, anti-electric field is caused to double, total voltage on air gap declines Δ U again, and electric discharge is extinguished again, when applied voltage continues to rise again, electric discharge repeats to occur successively, until to the not enough Δ U of the increment of peaking after a front discharge quenching, when namely the voltage of the total electric field of air gap does not reach Us, electric discharge no longer occurs.After this, applied voltage starts to reduce after peak value, and when the difference of the electric field being reduced to anti-electric field that space charge sets up and applied voltage reaches the breakdown field strength of air gap (n Δ U-Ug=Us), air gap starts back discharge, space charge reduces, and anti-electric field reduces makes discharge quenching.When applied voltage continues when increasing in the other direction, electric discharge then constantly occurs, and is formed and former opposite polarity space charge field in air gap, until the discharge process in applied voltage one week completes.
3. resistance to platen press test step by step
Certain temperature is maintained to cable sample, and imposes certain voltage simultaneously and having the state under certain loading condition with dummycable, then carry out mathematic(al) expectation by anti-power law.Temperature can select the long-term working temperature allowed usually, and to crosslinked cable that is 90 DEG C, the way taked in this test forms loop to sample to be realized by heating transformer.The applying of voltage can be constant voltage, also can be the voltage raised step by step, also can be ramp type boosting.Constant voltage can be regarded as withstand voltage step by step in a special case, namely progression is the withstand voltage test step by step of.
Adopt flash test step by step, on the sample of cable of various sample group, according to the difference boosting parameter of regulation, as voltage ratio, pressing time etc., apply power-frequency voltage respectively, obtain the breakdown time of the sample of each test group.Fig. 4 be step by step flash test boosting curve.
First apply 2.5U0 alternating voltage 15min to sample in the present embodiment, be next step-length boosted voltage step by step with 0.25U0, every one-level continues 15min, and till puncturing, test keeps conductor temperature at 90 DEG C (± 3 DEG C) therebetween.Record voltage breakdown and the last straw duration of each cable sample.
Adopt resistance to platen press step by step to determine, what can obtain every step voltage of cable and the last straw punctures the duration, utilizes anti-power formula
Calculate the residual life of cable.Wherein, E
irepresent the alternating voltage that every one-level applies sample, T
irepresent the time that every one-level alternating voltage is corresponding to sample effect, U represents voltage corresponding to calculation sample residual life, the residual life of T representative sample under voltage U.According to historical conditions at that time and productive capacity, the life index of crosslinked cable gets n=9 more.
4. isothermal relaxation current method test
Isothermal relaxation current method uses at Europe early start, subsequently Germany etc. the Western European countries this has been done to a large amount of research work, correlativity between the cable residual life obtain isothermal relaxation current spectrum and destructive test method is analyzed, find to there is clear and definite mathematics corresponding relation between isothermal relaxation current spectrum and residual life, and establish complete database accordingly, be used to guide cable life evaluation work.The XLPE of cable insulation and interior outer semiconducting layer are considered as an electrode-medium system, as shown in Figure 5.Apply DC polarization voltage to this system, in polarization process, electric charge is filled in these defects.After having polarized, carrying out short circuit dischange process to system, will there is transition in the electric charge be so filled in polarization process in defect.Keep environment temperature substantially constant, be in the electric charge of darker potential well, the time of transition is longer.These transition electric charge out, shows as a short-circuit current in external circuit.The size of short-circuit current shows the number of the defect in cable insulation, and short-circuit current over time, then indicate the position distribution of potential well residing for defect in cable insulation, and the wiring diagram of isothermal relaxation current method as shown in Figure 6.
First test cable is carried out pre-service: strip cable two ends external shielding layer, be stripped part washes of absolute alcohol dirt simultaneously, the surperficial Leakage Current in measuring process is reduced as much as possible.Reliably insulate in test article one end, another termination polarization high-voltage DC power supply, and conductor just connects, outer metallic shield ground connection, polarization time 1800s.Adopt and computerized control, the lax electric current of record, the sampling rate of electric current is 2Sa/s (Sample/sencond).
Will there is transition in the electric charge be filled in polarization process in defect, thermoelectron effusion medium, only need the trap area considering more than Fermi level, the relation of trap depth Et and time t can be expressed as
E
T(t)＝E
C-E
tn＝kt·ln(νt) (2)
The Isothermal Decay relation of the depolarization current in major insulation and time can be expressed as
In formula, k is Boltzmann constant, and t is die-away time, T is absolute temperature, and q is electronic charge, and ν is electronic vibration frequency, L is the thickness of insulation, and f0 (E) represents the initial density of electron trap, the distribution density that N (E) is trap level.By (3) Shi Ke get, product I (t) t of electric current and time and trap density N (E) linearly proportionate relationship.The change of I (t) t can characterize the electron trap distribution situation of more than Fermi level.
Polarization process comprises three kinds and is respectively: main body polarization, amorphous with the impact of crystal interface, the impact due to the slaine in aging interface of causing and hydrated ion.Can come equivalent with three pairs of resistance capacitance parallel circuits, equivalent electrical circuit as shown in Figure 5.So available three rank decaying exponential functions carry out matching to isothermal relaxation electric current
Wherein parameter a
i, τ
irelevant with the characteristic of dielectric substance, a
ireflect the density of trap, τ
i(=RiCi) reflects the degree of depth of trap, I
0indicate steady-state value when cable finally reaches balance.
Timeconstantτ
3correspond to the impact of salt in aging interface of causing and hydrated ion, associated parameter can become large along with the aggravation of degree of aging, and timeconstantτ
2corresponding to the impact at metamict crystals interface, in aging process, associated parameter is substantially constant.6 samples are tested respectively before and after thermal-electrical aging, the lax electric current under adopting computer recording isothermy in experimentation in each cable.So in practice, conventional timeconstantτ
2and τ
3time depolarization current calculate aging factor
Carry out can be calculated different sample aging factor M value according to formula (5).
Isothermal relaxation current method is adopted to test by the amorphous polarization current I (τ produced with crystal interface in the present embodiment
2) and the polarization current I (τ that produces due to the slaine in aging interface of causing and hydrated ion
3), and record the I (τ of not t in the same time
2), I (τ
3) value;
Polarization current I (τ is calculated respectively according to following formula
2), I (τ
3) corresponding timeconstantτ 2, τ 3;
Wherein, a2, a3 are the characteristic constant with dielectric substance.
Can be obtained by Fig. 8, the aging factor of aging front each sample is within the scope of 1.6-2.6.Through the aging factor Distribution value of the long cable sample of burin-in process within 1.9-2.8 scopes.Aging front and back, the aging factor difference of each sample is between 0.2-0.5.Known, slack-off through the overaging cable depolarization current rate of decay, along with insulation ag(e)ing, internal defects and micropore increase gradually, there is a large amount of trap level in insulating material inside, electric charge is not easy therefrom to depart from after entering trap, aging factor is reflected as aging factor M bigger than normal, and namely cable aging conditions is more serious.
According to remaining voltage breakdown criterion (because this criterion originates from Germany the earliest, so also known as German criterion), the relation of aging factor and remaining voltage breakdown can be obtained, as shown in the following Table 1.
Isothermal relaxation current method result before and after table 1 sample thermal-electrical aging
Draw according to table 1, before thermal-electrical aging process, S1 and F1 is in serious aging state, and corresponding cable should be changed in time; S2 and F2 is in middle aged state, and corresponding cable should carry out real time on-line monitoring work; S3 and S4 is in very good state, does not need to change cable.Result shows that working time is longer, aging more serious.
After thermal-electrical aging, S1, S2, F1, F2 are serious deterioration state; S3, S4 are senile state.And aging factor more aging before all corresponding increase.
Test cable was sorted out by manufacturer and time of putting into operation, obtains Fig. 9.By Tu Ke get: in the cable produced by SUMITOMO CHEMICAL, the cable that the cable aging factor dropped into for 1996 dropped into than 1985 is little.Illustrate that working time is longer, various insulation defect progressively develops, aging more serious.
In the cable that making time is close, Furukawa produce cable aging factor produce than Sumitomo large 10%, illustrate that the production technology of different manufacturers exists certain difference, make the quality of insulation of cable different.
Test the cable sample chosen to have and differently run the time limit, isothermal relaxation current method can find the difference of Different years cable ageing state, can the ageing state of comparatively accurate evaluation cable, has clear and definite directive significance.
From German criterion, the voltage breakdown scope that each ageing state is corresponding is more wide in range, and the result therefore obtained according to aging factor is a kind of judgement of tendency.
Instant invention overcomes the drawback of traditional single method research cable aging conditions, on the one hand, the result that isothermal relaxation current method obtains is as the judgement of tendency, in order to judge the roughly degree that cable is aging, and on the other hand, resistance to platen press result is as concrete judgement, the residual life of cable can be inferred, both combine and assess to determine whether to need to change to the aging conditions of cable, avoid the unilateral reflection of single method to assessment result, make result have more reference value.
Above-described embodiment is the present invention's preferably embodiment; but embodiments of the present invention are not restricted to the described embodiments; change, the modification done under other any does not deviate from Spirit Essence of the present invention and principle, substitute, combine, simplify; all should be the substitute mode of equivalence, be included within protection scope of the present invention.
Claims (9)
1. combine a cable aging assessment for resistance to platen press and isothermal relaxation current method step by step, it is characterized in that, comprise the following steps:
Resistance to platen press test procedure step by step, this step, by adopting flash test step by step on sample of cable to be assessed, according to the difference boosting parameter of regulation, applies power-frequency voltage step by step, obtain and record breakdown time of described sample of cable to be assessed, then calculating the residual life of described cable to be assessed;
Isothermal relaxation current method step, this step by accessing polarization high-voltage DC power supply on described sample of cable to be assessed, after the polarization time of fixed time length, utilize computer sampling record isothermal relaxation electric current, calculate the aging factor of described sample of cable to be assessed, then according to remaining voltage breakdown criterion, the relation of aging factor and remaining voltage breakdown is obtained.
2. the cable aging assessment of combination according to claim 1 resistance to platen press and isothermal relaxation current method step by step, it is characterized in that, described boosting parameter comprises initial on-load voltage, step size voltage, pressing time.
3. the cable aging assessment of combination according to claim 2 resistance to platen press and isothermal relaxation current method step by step, it is characterized in that, the detailed process of described resistance to platen press test procedure is step by step:
S11,2.5U is applied to described sample of cable to be assessed
0alternating voltage as described initial on-load voltage, next with 0.25U
0raise on-load voltage step by step as described step size voltage, wherein every one-level on-load voltage continues 15min, till puncturing, records voltage breakdown and the last straw duration of described sample of cable to be assessed;
S12, utilize anti-power formula
calculate the residual life of cable to be assessed, wherein, E
irepresent the on-load voltage that every one-level applies described sample of cable to be assessed, T
irepresent every one-level on-load voltage to the time corresponding to described sample of cable effect to be assessed, U representative calculates voltage corresponding to described sample of cable residual life to be assessed, T represents the residual life of described sample of cable to be assessed under voltage U, and n represents the life index of described sample of cable to be assessed.
4. the cable aging assessment of combination according to claim 1 resistance to platen press and isothermal relaxation current method step by step, it is characterized in that, the detailed process of described isothermal relaxation current method step is:
S21, pre-service is carried out to described sample of cable to be assessed, strip cable sample two ends external shielding layer, and reliably insulate in one end, another termination polarization high-voltage DC power supply, wherein conductor just connects, outer metallic shield ground connection, polarizes fixed time P second with high-voltage DC power supply, controlled by computing machine, the electric current and sample record record relaxes;
S22, pass through following formula
Calculate the aging factor M value of described sample of cable to be assessed, wherein, timeconstantτ
3salt in corresponding aging interface of causing and the impact of hydrated ion, timeconstantτ
2the impact at corresponding metamict crystals interface, adopts the test of isothermal relaxation current method by the amorphous polarization current I (τ produced with crystal interface
2) and the polarization current I (τ that produces due to the slaine in aging interface of causing and hydrated ion
3), and record the I (τ of not t in the same time
2), I (τ
3) value;
S23, according to remaining voltage breakdown criterion, obtain the relation of aging factor and remaining voltage breakdown.
5. the cable aging assessment of combination according to claim 3 resistance to platen press and isothermal relaxation current method step by step, is characterized in that,
The historical conditions that described life index n produces according to cable to be assessed and productive capacity determine, wherein when described sample of cable to be assessed is XLPE cable, and life index n=9.
6. the cable aging assessment of combination according to claim 3 resistance to platen press and isothermal relaxation current method step by step, is characterized in that,
Described sample of cable to be assessed carries out keeping conductor temperature in [87 DEG C, 93 DEG C] temperature range in resistance to platen press process of the test step by step.
7. the cable aging assessment of combination according to claim 4 resistance to platen press and isothermal relaxation current method step by step, it is characterized in that, described sample of cable to be assessed carries out the fixed time P=1800 second with high-voltage DC power supply polarization in isothermal relaxation current method test procedure.
8. the cable aging assessment of combination according to claim 4 resistance to platen press and isothermal relaxation current method step by step, it is characterized in that, it is 2Sa/s that described sample of cable to be assessed carries out the relax sampling rate of electric current of sample record in isothermal relaxation current method test procedure.
9., according to the cable aging assessment of the arbitrary described combination of claim 1 to 8 resistance to platen press and isothermal relaxation current method step by step, it is characterized in that, also comprise the following steps:
Partial discharge test step, this step, by carrying out partial discharge test to described sample of cable to be assessed, contrasts according to the Apparent discharge magnitude recorded and GB/T 11017.2-2002, tentatively judges the ageing state of described sample of cable to be assessed.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510113947.8A CN104730436A (en) | 2015-03-16 | 2015-03-16 | Cable aging estimation method combining step-by-step withstand voltage method and isothermal relaxation current method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510113947.8A CN104730436A (en) | 2015-03-16 | 2015-03-16 | Cable aging estimation method combining step-by-step withstand voltage method and isothermal relaxation current method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN104730436A true CN104730436A (en) | 2015-06-24 |
Family
ID=53454518
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510113947.8A Pending CN104730436A (en) | 2015-03-16 | 2015-03-16 | Cable aging estimation method combining step-by-step withstand voltage method and isothermal relaxation current method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104730436A (en) |
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105044157A (en) * | 2015-08-13 | 2015-11-11 | 国网山东省电力公司潍坊供电公司 | Isothermal relaxation current principle-based basin-type insulator nondestructive testing device and method |
| CN106597238A (en) * | 2016-12-27 | 2017-04-26 | 国网河北省电力公司电力科学研究院 | Equipment and method utilizing isothermal relaxation current to evaluate aging state of fluorescence fiber temperature sensor sheath in transformer |
| CN107462815A (en) * | 2017-06-26 | 2017-12-12 | 全球能源互联网欧洲研究院 | A kind of cable insulation thermal breakdown voltage determines method and apparatus |
| CN107505542A (en) * | 2017-07-25 | 2017-12-22 | 上海电力学院 | Measuring method based on depolarization current method detection XLPE cable degree of aging |
| CN109142992A (en) * | 2018-07-11 | 2019-01-04 | 国网上海市电力公司 | A kind of 35 KV cross-linked cable insulation ag(e)ing state evaluating methods |
| CN110850196A (en) * | 2019-10-21 | 2020-02-28 | 国网吉林省电力有限公司长春供电公司 | Service life electric stress and/or thermal stress test platform for crosslinked polyethylene power cable |
| CN111157854A (en) * | 2019-12-31 | 2020-05-15 | 国家电网有限公司 | Method and device for processing residual life of cable, storage medium and processor |
| CN111650479A (en) * | 2020-04-03 | 2020-09-11 | 国网吉林省电力有限公司长春供电公司 | IRC (infrared radiation correlation) and electrothermal accelerated aging test method |
| CN111693827A (en) * | 2020-05-21 | 2020-09-22 | 国网河北省电力有限公司电力科学研究院 | Cable water tree severity diagnosis method based on cosine square wave pressure resistance test |
| CN113777138A (en) * | 2021-09-07 | 2021-12-10 | 上海交通大学 | Insulation material aging state evaluation method based on linear boosting and isothermal relaxation current |
| CN115808603A (en) * | 2023-02-16 | 2023-03-17 | 江苏盛华电气有限公司 | High-voltage cable voltage withstand test system and method |
| CN116106657A (en) * | 2022-11-18 | 2023-05-12 | 西南交通大学 | Method for evaluating ageing state of EPDM (ethylene-propylene-diene monomer) cable based on electron trap effect |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102944777A (en) * | 2012-10-31 | 2013-02-27 | 广州供电局有限公司 | Method for detecting service life of cable |
| CN103472363A (en) * | 2012-06-06 | 2013-12-25 | 宝山钢铁股份有限公司 | Crosslinked polyethylene cable residual life assessment method |
-
2015
- 2015-03-16 CN CN201510113947.8A patent/CN104730436A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103472363A (en) * | 2012-06-06 | 2013-12-25 | 宝山钢铁股份有限公司 | Crosslinked polyethylene cable residual life assessment method |
| CN102944777A (en) * | 2012-10-31 | 2013-02-27 | 广州供电局有限公司 | Method for detecting service life of cable |
Non-Patent Citations (6)
| Title |
|---|
| BOLARIN S. OYEGOKE ET AL.: "Condition Assessment of XLPE Insulated Cables Using Isothermal Relaxation Current Technique", 《POWER ENGINEERING SOCIETY GENERAL MEETING，2006.IEEE》 * |
| J.R.LAGHARI ET AL.: "A Short Method of Estimating Lifetime of Polypropylene Film using Step-stress Tests", 《IEEE TRANSACTIONS ON ELECTRICAL INSULATION》 * |
| 喻岩珑 等: "XLPE电缆绝缘老化与剩余寿命评估的试验方法", 《电网与清洁能源》 * |
| 杨丽君 等: "用逐步升压法和Weibull参数估计油纸绝缘寿命", 《高电压技术》 * |
| 王雅群 等: "等温松弛电流用于10kV XLPE电缆寿命评估的方法", 《电工技术学报》 * |
| 胡加励: "高压XLPE绝缘电力电缆的电老化与寿命估计", 《哈尔滨电工学院学报》 * |
Cited By (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105044157A (en) * | 2015-08-13 | 2015-11-11 | 国网山东省电力公司潍坊供电公司 | Isothermal relaxation current principle-based basin-type insulator nondestructive testing device and method |
| CN106597238A (en) * | 2016-12-27 | 2017-04-26 | 国网河北省电力公司电力科学研究院 | Equipment and method utilizing isothermal relaxation current to evaluate aging state of fluorescence fiber temperature sensor sheath in transformer |
| CN107462815A (en) * | 2017-06-26 | 2017-12-12 | 全球能源互联网欧洲研究院 | A kind of cable insulation thermal breakdown voltage determines method and apparatus |
| CN107462815B (en) * | 2017-06-26 | 2020-02-07 | 全球能源互联网欧洲研究院 | Cable insulation thermal breakdown voltage determining method and device |
| CN107505542A (en) * | 2017-07-25 | 2017-12-22 | 上海电力学院 | Measuring method based on depolarization current method detection XLPE cable degree of aging |
| CN109142992A (en) * | 2018-07-11 | 2019-01-04 | 国网上海市电力公司 | A kind of 35 KV cross-linked cable insulation ag(e)ing state evaluating methods |
| CN110850196A (en) * | 2019-10-21 | 2020-02-28 | 国网吉林省电力有限公司长春供电公司 | Service life electric stress and/or thermal stress test platform for crosslinked polyethylene power cable |
| CN111157854A (en) * | 2019-12-31 | 2020-05-15 | 国家电网有限公司 | Method and device for processing residual life of cable, storage medium and processor |
| CN111650479A (en) * | 2020-04-03 | 2020-09-11 | 国网吉林省电力有限公司长春供电公司 | IRC (infrared radiation correlation) and electrothermal accelerated aging test method |
| CN111693827A (en) * | 2020-05-21 | 2020-09-22 | 国网河北省电力有限公司电力科学研究院 | Cable water tree severity diagnosis method based on cosine square wave pressure resistance test |
| CN111693827B (en) * | 2020-05-21 | 2023-01-13 | 国网河北省电力有限公司电力科学研究院 | Method for diagnosing severity of cable water tree based on cosine square wave voltage withstand test |
| CN113777138A (en) * | 2021-09-07 | 2021-12-10 | 上海交通大学 | Insulation material aging state evaluation method based on linear boosting and isothermal relaxation current |
| CN113777138B (en) * | 2021-09-07 | 2022-08-30 | 上海交通大学 | Insulation material aging state evaluation method based on linear boosting and isothermal relaxation current |
| CN116106657A (en) * | 2022-11-18 | 2023-05-12 | 西南交通大学 | Method for evaluating ageing state of EPDM (ethylene-propylene-diene monomer) cable based on electron trap effect |
| CN116106657B (en) * | 2022-11-18 | 2024-03-19 | 西南交通大学 | Method for evaluating ageing state of EPDM (ethylene-propylene-diene monomer) cable based on electron trap effect |
| CN115808603A (en) * | 2023-02-16 | 2023-03-17 | 江苏盛华电气有限公司 | High-voltage cable voltage withstand test system and method |
| CN115808603B (en) * | 2023-02-16 | 2023-09-22 | 江苏盛华电气有限公司 | High-voltage cable withstand voltage test system and method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104730436A (en) | Cable aging estimation method combining step-by-step withstand voltage method and isothermal relaxation current method | |
| CN103149452B (en) | Method for evaluating ageing state of paper oil insulation | |
| CN102944777B (en) | Cable detection method in serviceable life | |
| CN110297167B (en) | Transformer aging state evaluation method based on multi-source information fusion | |
| CN110736905A (en) | Insulation aging evaluation method for 110kV XLPE high-voltage cable | |
| CN108089038B (en) | Test device and method for analyzing influence of winding defect heating on oil paper insulation performance | |
| Babel et al. | Condition-based monitoring and prognostic health management of electric machine stator winding insulation | |
| CN102830309A (en) | Testing method for aging factor of 110 kV cross-linked cable | |
| CN102540029B (en) | Method for calculating partial discharge failure probability of oil paper insulating equipment | |
| CN106093614A (en) | A kind of method of return voltage initial slope assessment transformer insulation state | |
| CN111157854A (en) | Method and device for processing residual life of cable, storage medium and processor | |
| CN109142992A (en) | A kind of 35 KV cross-linked cable insulation ag(e)ing state evaluating methods | |
| CN111650479A (en) | IRC (infrared radiation correlation) and electrothermal accelerated aging test method | |
| CN105116201A (en) | Measuring device and method for return voltage parameter | |
| Das et al. | A novel approach to estimate the quantity of ingressed moisture content inside metal oxide surge arrester using dielectric modulus technique | |
| CN111337797A (en) | XLPE power cable main insulation non-uniform thermal aging state evaluation method based on modified Debye model | |
| CN102540030B (en) | Method for diagnosing development speed of partial discharge defect of oil paper insulated equipment | |
| CN106443129A (en) | Numerical computation method for recovery voltage of electrical equipment and insulating material | |
| CN116359690A (en) | Testing device for double-layer composite insulation isothermal relaxation current and aging evaluation model thereof | |
| CN102147440A (en) | Method for diagnosing partial discharge defect severity of paper oil insulating edge surface of transformer | |
| CN112485614A (en) | Voltage withstand test method and device for cable insulating material | |
| CN104635066A (en) | Intelligent insulation parameter test residual charge detecting and discharging protection method | |
| Zhang et al. | Research on conversion of polarization/depolarization current and frequency domain spectroscopy for XLPE cable | |
| Li et al. | Studies of the polarization/depolarization current characteristics of XLPE cable | |
| Talib et al. | Diagnosis of transformer insulation condition using recovery voltage measurements |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WD01 | Invention patent application deemed withdrawn after publication | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20150624 |