CN103091607A - Electromagnetic characteristic parameter extracting method of high voltage cable insulation defect in different exciting fields - Google Patents
Electromagnetic characteristic parameter extracting method of high voltage cable insulation defect in different exciting fields Download PDFInfo
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- CN103091607A CN103091607A CN2012105596394A CN201210559639A CN103091607A CN 103091607 A CN103091607 A CN 103091607A CN 2012105596394 A CN2012105596394 A CN 2012105596394A CN 201210559639 A CN201210559639 A CN 201210559639A CN 103091607 A CN103091607 A CN 103091607A
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Abstract
The invention provides an electromagnetic characteristic parameter extracting method of a high voltage cable insulation defect in different exciting fields. The theory of the electromagnetic characteristic parameter extracting method of the high voltage cable insulation defect in the different exciting fields is that high voltage extrusion insulation cables of a coaxial structure can approximate and equivalent to a capacitor; and by using the characteristic that transient pulse current formed by quick move of electric charge can excite an electromagnetic wave which propagates in a cavity of a coaxial capacitor and through the fact that metal copper foil winds and wraps on a metal sleeve, a cylindrical monopole sub-antenna sensor used as an electromagnetic search antenna for collecting electromagnetic signals which propagate in the cable of partial discharge is formed. The electromagnetic characteristic parameter extracting method of the high voltage cable insulation defect in different exciting fields can resolve the realistic problem that the electromagnetic characteristic parameter collecting method of macroscopic characteristic quantity of the high voltage extrusion insulation cables in different exciting fields in current domestic or overseas is deficient, at the same time can guide electrical equipment quality inspection and test organizations on how to uniformly evaluate the insulation quality of the high voltage extrusion insulation cables in different exciting fields for electrical system users, and at the same time facilitates the optimization and improvement of product quality and product performance by cable manufactures.
Description
Technical field
The invention belongs to high-voltage test and Insulation test technical field, relate to the electromagnetic signature parameter extracting method of the multiple dimensioned insulation defect of high-tension cable under a kind of different exciting field, be applicable to 110kV(AC) or ± 100kV(DC) above is extruded insulated power cable.
Background technology
Along with fast development and the upgrading of China's urban distribution network, crosslinked polyethylene (XLPE is hereinafter to be referred as crosslinked) cable has been widely used in exchanging in electric line as power cable engineering main product.Over past ten years, crosslinked cable lays loop length to surpass 15% annual average rate of increase steady-state growth.High pressure, ultra-high voltage cross-linking cable circuit have become the important component part of China's AC network.
Than the high-voltage AC transmission form, D.C. high voltage transmission has many advantages: cost is low, line loss is little, substantially there is no reactive power, electric power is easy to connect, easily control and regulate, and especially direct current power system extensively adopts in long distance powedr transmission.Compare with ac power cable, insulation DC electric cable has following advantages: the applied electric field intensity of insulation is high, and insulation thickness is thin, and the outside diameter of cable is little, lightweight, manufacturing is installed easily; Dielectric loss and conductor losses are low, and current-carrying capacity is large; There is no AC magnetic field, the advantage of environmental protection aspect is arranged.In the direct current cables product, compare with the insulation impregnating direct current cables, extrusion type high voltage direct current cable environmental pollution is little, good heat resistance, easy care, lightweight, long Distance Transmission need not joint.
At present, international well-known test for identification mechanism such as the KEMA of Holland, gondola CESI have every test capability of 500kV and following ac power cable.At present along with the development of direct current cables in the world, well-known power cable test chamber is all at the test capability of development 500kV and following direct current cables in the world, but the recommendation test specification of CIGRE is only arranged due to the IEC standard that there is no direct current cables at present, and therefore the test of international direct current cables examination technology and ability are also unripe yet.CIGRE has proposed one " Recommendations for testing DC extruded cable systems for power transmission at a rated voltage up lo 250 kV " in February, 2003 by 21.0l group and has recommended test method, but its recommend method has also only proposed the test clause that can carry out in factory's development experiments, mainly comprise: duty cycle, recirculate, reversal of poles, zero load, superimposed pulses test, there is no that detailed method requires or regulation.
Correlative study shows, shelf depreciation (Partial Discharge is hereinafter to be referred as PD) as the main forms of the early stage insulation fault of cable line, is the main cause that causes insulation ag(e)ing, is again the principal character parameter that characterizes insulation status.From extruding the dielectric property of insulated cable, no matter be ac high-voltage cable or direct current high voltage cable, the multiple dimensioned insulation defects such as its inner as insulation air gap, conductor burr, semiconduction tip, micropore impurity are under the excitation electrical field (being applied between cable conductor core and metallic sheath as industrial frequency AC, direct current, oscillatory extinction ripple) of different shape acts on, as long as rejected region is because space charge gathers, local electric field strength distorts to certain numerical value, must excite shelf depreciation, can be used as the microcosmic insulation defect macrofeature parameter of high-tension cable.Yet how the electromagnetic signature parameter for the multiple dimensioned insulation defect of high-tension cable under the different shape exciting field extracts with general unified technical method both at home and abroad, there is not yet relevant report, restricted high pressure and extruded the validity that the insulated cable quality of insulation is estimated, be unfavorable for that the work such as the research of space charge mechanism, the basic research of insulating material, cable quality verification test, cable line state evaluation carry out.
In view of this, the present invention proposes the electromagnetic signature parameter extracting method of the multiple dimensioned insulation defect of high-tension cable under a kind of different exciting field, extrude insulated cable macrofeature parameter under different excitation electrical field to fill up the outer high pressure of Present Domestic---the realistic problem of local discharge signal pick-up method disappearance, can instruct power equipment quality inspection mechanism for testing how to extrude the insulated cable quality of insulation for electric system user unified test and appraisal high pressure under different exciting fields, promote simultaneously the cables manufacturing business to optimize Improving The Quality of Products and performance.
Summary of the invention
The objective of the invention is to fill up the realistic problem that the outer high pressure of Present Domestic is extruded the electromagnetic signature parameter pick-up method disappearance of insulated cable macrofeature amount under different excitation electrical field, propose the electromagnetic signature parameter extracting method of the multiple dimensioned insulation defect of high-tension cable under a kind of different exciting field, be applicable to 110kV(AC) or ± 100kV(DC) above is extruded insulated power cable.
Technical scheme of the present invention is: the electromagnetic signature parameter extracting method of high-voltage cable insulating defective under different exciting fields, it is characterized in that, and comprise the steps:
First step in the electromagnetic screen laboratory, is extruded high pressure after insulated cable two ends install inflatable test sleeve, and going between by high-tension shielding is connected with the complex incentive voltage source;
Second step is drawn direct ground connection at the near-end near voltage source with the cable metal cover, at the far-end away from voltage source, cable jacket is done ring cutting processing, the metallic sheath face of cylinder of exposing width L=10cm;
Third step, wrapped a layer thickness d=0.5mm on the metallic sheath face of cylinder, width is
lThe metal copper foil of=10cm, Copper Foil seam argon arc welding;
The 4th step is soldered to the heart yearn of the coaxial cable of radiofrequency signal on Copper Foil the direct ground connection of coaxial cable screen layer; The coaxial cable of radiofrequency signal is connected with high-speed wideband oscillograph input channel;
The 5th step starts the complex incentive voltage source, at first extrudes insulated cable to high pressure and applies the industrial frequency AC driving voltage, the voltage source linearity is set boosts;
The 6th step, the signal that observation oscilloscope gathers, if the pulse electromagnetic wave signal occurs, burning voltage duration T=60S, gather and the analytic signal frequency domain character;
The 7th step if the no pulse electromagnetic wave signal continues to boost to higher limit, then stops pressurization;
The 8th step is extruded insulated cable to high pressure and is applied continuous-current excitation voltage, the voltage source linearity is set boosts;
The 9th step, the signal that observation oscilloscope gathers if the pulse electromagnetic wave signal occurs, gathers the also frequency domain character of analytic signal;
The tenth step if the no pulse electromagnetic wave signal continues to boost to higher limit, then stops pressurization, still will gather and record the input signal of duration t=60S after stopping pressurizeing, and whether inspires the reversed polarity discharge in order to observe the cable internal electric field;
The 11 step is extruded insulated cable to high pressure and is applied the damp oscillatory wave driving voltage, the voltage source staged is set boosts, the 10kV/ level;
The 12 step is at the signal of observation oscilloscope collection; If the pulse electromagnetic wave signal occurs, to repeat to pressurize N time under the current voltage value, 20≤N≤50 gather the also frequency domain character of analytic signal;
The 13 step, if the no pulse electromagnetic wave signal, ladder boosts to higher limit, then stops pressurization.
the electromagnetic signature parameter extracting method of high-voltage cable insulating defective under different exciting field as above, it is characterized in that: it is capacitor that the high pressure of coaxial configuration is extruded the insulated cable Approximate Equivalent, cable conductor is the high-field electrode of capacitor, the cable metal cover is the non-high-field electrode of capacitor, no matter under which kind of exciting field effect, the inner shelf depreciation of solid insulating material is comprised of two inequalities signal intensity that is mutually related again in fact, it is the accumulation of a large amount of electric charges, exchange and the electromagnetic disturbance that causes because of the electric charge fast transferring, the transient pulse current excitation that the electric charge fast transferring forms goes out the electromagnetic wave of propagating in the ganged condenser cavity, and on metallic sheath wrapped metal copper foil, form exactly cylinder monopole antenna sensor, with it as the electromagnetic wave detection antenna, be used for picking up the electromagnetic wave signal that shelf depreciation is propagated in cable.
The invention has the beneficial effects as follows: the present invention proposes the electromagnetic signature parameter extracting method of the multiple dimensioned insulation defect of high-tension cable under a kind of different exciting field, extrude the realistic problem of the electromagnetic signature parameter pick-up method disappearance of insulated cable macrofeature amount under different excitation electrical field to fill up the outer high pressure of Present Domestic, be applicable to 110kV(AC) or ± 100kV(DC) above is extruded insulated power cable.Can instruct simultaneously power equipment quality inspection mechanism for testing how to extrude the insulated cable quality of insulation for electric system user unified test and appraisal high pressure under different exciting fields, promote simultaneously the cables manufacturing business to optimize Improving The Quality of Products and performance.
Description of drawings
Fig. 1 is the electromagnetic signature parameter extracting method schematic diagram of high-voltage cable insulating defective under different exciting field of the present invention.
Fig. 2 is electromagnetic signature parameter pickoff sensor structural representation of the present invention.
Embodiment
In order to understand better the present invention, further illustrate content of the present invention below in conjunction with embodiment, but content of the present invention not only is confined to the following examples.Those skilled in the art can make various changes or modifications the present invention, and these equivalent form of values are equally within the listed claims limited range of the application.
Description of symbols in Fig. 1,11-complex incentive voltage source, 12-high-tension shielding lead-in wire, 13-inflatable test sleeve, 14-metallic sheath ground wire, the 15-high pressure is extruded insulated cable, 16-metal copper foil, the coaxial cable of 17-radiofrequency signal, 18-high-speed wideband oscillograph.
Description of symbols in Fig. 2,21-oversheath, 22-protective metal shell, 23-out semiconductor layer, 24-major insulation, 25-metal copper foil, semi-conductive layer in 26-conductor thread core, 27-, 28-signal output part.
The electromagnetic signature parameter extracting method of the multiple dimensioned insulation defect of high-tension cable under the different exciting fields that the embodiment of the present invention provides, its specific implementation method is:
First step in the electromagnetic screen laboratory, is extruded high pressure after insulated cable two ends install inflatable test sleeve, and going between by high-tension shielding is connected with the complex incentive voltage source;
Second step is drawn direct ground connection at the near-end near voltage source with the cable metal cover, at the far-end away from voltage source, cable jacket is done ring cutting processing, the metallic sheath face of cylinder of exposing width L=10cm;
Third step, wrapped a layer thickness d=0.5mm on the metallic sheath face of cylinder, width is the metal copper foil of l=10cm, Copper Foil seam argon arc welding;
The 4th step is soldered to the heart yearn of the coaxial cable of radiofrequency signal on Copper Foil the direct ground connection of coaxial cable screen layer; The coaxial cable of radiofrequency signal is connected with high-speed wideband oscillograph input channel;
The 5th step starts the complex incentive voltage source, at first extrudes insulated cable to high pressure and applies the industrial frequency AC driving voltage, the voltage source linearity is set boosts;
The 6th step, the signal that observation oscilloscope gathers, if the pulse electromagnetic wave signal occurs, burning voltage duration T=60S, gather and the analytic signal frequency domain character;
The 7th step if the no pulse electromagnetic wave signal continues to boost to higher limit, then stops pressurization;
The 8th step is extruded insulated cable to high pressure and is applied continuous-current excitation voltage, the voltage source linearity is set boosts;
The 9th step, the signal that observation oscilloscope gathers if the pulse electromagnetic wave signal occurs, gathers the also frequency domain character of analytic signal;
The tenth step if the no pulse electromagnetic wave signal continues to boost to higher limit, then stops pressurization, still will gather and record the input signal of duration t=60S after stopping pressurizeing, and whether inspires the reversed polarity discharge in order to observe the cable internal electric field;
The 11 step is extruded insulated cable to high pressure and is applied the damp oscillatory wave driving voltage, the voltage source staged is set boosts, the 10kV/ level;
The 12 step is at the signal of observation oscilloscope collection; If the pulse electromagnetic wave signal occurs, repeat to pressurize under the current voltage value N time (20≤N≤50), gather the also frequency domain character of analytic signal;
The 13 step, if the no pulse electromagnetic wave signal, ladder boosts to higher limit, then stops pressurization.
The present embodiment the 6th step burning voltage time span T=60S, the 11 step collection is also recorded duration t=60S.In practical operation, T and t can arrange flexibly according to the signal analysis needs, generally should get T or t value 60 or 60S above for good.
The central principle that the electromagnetic signature parameter extracts is: but to extrude the insulated cable Approximate Equivalent be capacitor to the high pressure of coaxial configuration, cable conductor is the high-field electrode of capacitor, the cable metal cover is the non-high-field electrode of capacitor.No matter under which kind of exciting field effect, the inner shelf depreciation of solid insulating material is comprised of two inequalities signal intensity that is mutually related again in fact---the accumulation of a large amount of electric charges, exchange and the electromagnetic disturbance that causes because of the electric charge fast transferring.In the IEC60270 standard, pulse current method is exactly to complete the time space electric charge by coupling condenser and detection impedance measurement shelf depreciation to redistribute the change in voltage that causes cable conductor and metallic sheath two ends generation.The transient pulse electric current that the electric charge fast transferring forms can motivate the electromagnetic wave of propagating in the ganged condenser cavity, and on metallic sheath wrapped metal copper foil, form exactly cylinder monopole antenna sensor, it as the electromagnetic wave detection antenna, is used for picking up the electromagnetic wave signal that shelf depreciation is propagated in cable.
The electromagnetic signature parameter extracting method of the multiple dimensioned insulation defect of high-tension cable under different exciting field provided by the invention, be with the key distinction of prior art: the pulse current method that the Partial Discharge Detection of domestic and international existing cable insulation defective generally adopts IEC60270 to recommend, in non-standard method, the electromagnetic signature parameter of UHF coupled method extraction local discharge signal is also only depressed based on industrial-frequency alternating current, do not extend and do not expand to the excitation electrical field of different shape, and only for cable GIS(combined closing electrical equipment) Partial Discharge Detection of terminal is just more effective.How to extract the electromagnetic signature parameter of the multiple dimensioned insulation defect of high-tension cable under different exciting fields, except the method that the present invention proposes, also do not have at present corresponding method and technological means to realize.
The content that is not described in detail in this instructions belongs to the known prior art of this area professional and technical personnel.
Claims (2)
1. the electromagnetic signature parameter extracting method of high-voltage cable insulating defective under different exciting fields, is characterized in that, comprises the steps:
First step in the electromagnetic screen laboratory, is extruded high pressure after insulated cable two ends install inflatable test sleeve, and going between by high-tension shielding is connected with the complex incentive voltage source;
Second step is drawn direct ground connection at the near-end near voltage source with the cable metal cover, at the far-end away from voltage source, cable jacket is done ring cutting processing, the metallic sheath face of cylinder of exposing width L=10cm;
Third step, wrapped a layer thickness d=0.5mm on the metallic sheath face of cylinder, width is
lThe metal copper foil of=10cm, Copper Foil seam argon arc welding;
The 4th step is soldered to the heart yearn of the coaxial cable of radiofrequency signal on Copper Foil the direct ground connection of coaxial cable screen layer; The coaxial cable of radiofrequency signal is connected with high-speed wideband oscillograph input channel;
The 5th step starts the complex incentive voltage source, at first extrudes insulated cable to high pressure and applies the industrial frequency AC driving voltage, the voltage source linearity is set boosts;
The 6th step, the signal that observation oscilloscope gathers, if the pulse electromagnetic wave signal occurs, burning voltage duration T 〉=60S, gather and the analytic signal frequency domain character;
The 7th step if the no pulse electromagnetic wave signal continues to boost to higher limit, then stops pressurization;
The 8th step is extruded insulated cable to high pressure and is applied continuous-current excitation voltage, the voltage source linearity is set boosts;
The 9th step, the signal that observation oscilloscope gathers if the pulse electromagnetic wave signal occurs, gathers the also frequency domain character of analytic signal;
The tenth step if the no pulse electromagnetic wave signal continues to boost to higher limit, then stops pressurization, still will gather and record the input signal of duration t 〉=60S after stopping pressurizeing, and whether inspires the reversed polarity discharge in order to observe the cable internal electric field;
The 11 step is extruded insulated cable to high pressure and is applied the damp oscillatory wave driving voltage, the voltage source staged is set boosts, the 10kV/ level;
The 12 step is at the signal of observation oscilloscope collection; If the pulse electromagnetic wave signal occurs, to repeat to pressurize N time under the current voltage value, 20≤N≤50 gather the also frequency domain character of analytic signal;
The 13 step, if the no pulse electromagnetic wave signal, ladder boosts to higher limit, then stops pressurization.
2. the electromagnetic signature parameter extracting method of high-voltage cable insulating defective under different exciting field according to claim 1, it is characterized in that: it is capacitor that the high pressure of coaxial configuration is extruded the insulated cable Approximate Equivalent, cable conductor is the high-field electrode of capacitor, the cable metal cover is the non-high-field electrode of capacitor, no matter under which kind of exciting field effect, the inner shelf depreciation of solid insulating material is comprised of two inequalities signal intensity that is mutually related again in fact, it is the accumulation of a large amount of electric charges, exchange and the electromagnetic disturbance that causes because of the electric charge fast transferring, the transient pulse current excitation that the electric charge fast transferring forms goes out the electromagnetic wave of propagating in the ganged condenser cavity, and on metallic sheath wrapped metal copper foil, form exactly cylinder monopole antenna sensor, with it as the electromagnetic wave detection antenna, be used for picking up the electromagnetic wave signal that shelf depreciation is propagated in cable.
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Cited By (5)
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| CN106646160A (en) * | 2016-12-13 | 2017-05-10 | 中国电力科学研究院 | Method, device and system for detecting insulating performances of extruded cable under different forms and voltages |
| CN108700632A (en) * | 2016-03-03 | 2018-10-23 | 住友电气工业株式会社 | Method for the insulation performance for assessing insulator |
| WO2019051659A1 (en) * | 2017-09-12 | 2019-03-21 | 青岛科技大学 | Semiconductor charge emission test method and apparatus |
| CN110531227A (en) * | 2019-08-16 | 2019-12-03 | 中国电力科学研究院有限公司 | A kind of device and method of the quality of insulation of detection high pressure extrusion cable |
| CN114465193A (en) * | 2022-01-11 | 2022-05-10 | 深圳市德拜科技有限公司 | Underwater sound wave generating device, control method, system and storage medium |
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Application publication date: 20130508 |