CN102680574A - GIS (Gas Insulated Switchgear) inner particle detecting method adopting polarity-reversal direct-current voltage - Google Patents
GIS (Gas Insulated Switchgear) inner particle detecting method adopting polarity-reversal direct-current voltage Download PDFInfo
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Abstract
The invention provides a GIS (Gas Insulated Switchgear) inner particle detecting method adopting a polarity-reversal direct-current voltage. According to the invention, the detects of metal particles are arranged in a GIS; and meanwhile, a corresponding device controls a direction selecting switch to be communicated with cathode direct-current voltage; in a GIS testing section, an ultrasonic signal level database is obtained before and after a rubber hammer is hammered when a linear particle, a spherical particle and a plurality of quantities (or lengths) of particles are combined, and a typical ultrasonic signal level difference and a quantitative standard under positive polarity direct-current voltage and negative polarity direct-current voltage are obtained by comparing; the corresponding device controls the direction selecting switch to connect a GIS high-voltage end to the positive polarity direct-current voltage for one minute; and then, the direction selecting switch is connected to the negative polarity direct-current voltage for one minute; and the process is lasted for 10 min back and forth, so as to eliminate influences on a space charge and a residual charge, caused by applying the direct-current voltage; and the metal particles in the GIS are distinguished. The method disclosed by the invention has the obvious advantages of simplicity, small power, easiness for operation, convenience for carrying and high sensitivity.
Description
Technical field
The invention belongs to GIS class inside electric appliance particle defects detection technique field, be particularly useful for the detection of GIS kind equipment interior metal particulate.
Background technology
GIS is because its volume is little, stable, the arc extinguishing ability is strong, usually is used for the electric system key area.Yet show that in GIS long-time running situation GIS has good insulating property, but regular meeting metal particle appears reduces its insulating property greatly when GIS is inner, is the maximum hidden danger of GIS safe and stable operation.Thereby the electric power research worker hopes that through the charged detection method of GIS metallic conducting particle in the GIS being removed perhaps dangerous metal particle is controlled at safer zone, avoids and eliminate GIS as far as possible because the security incident that the interior metal particulate causes.
At present; Insulation defect in the GIS; Especially the detection method of particle defects mainly is pulse current method, ultrasonic method, ultrahigh frequency method, and the metal particle defective all has its special advantages in these methods pair and the GIS, and has aspect the metal particle defective detects in actual GIS comparatively widely and use.These methods do not reach office when putting starting potential for metallic conducting particle, are can not produce the corona discharge phenomenon near the metal particle end, just do not have partial discharge phenomenon yet.Though metal particle can be electrically charged under the high field intensity effect; Can strong effect under electric field action and take-off or motion, be referred to as " flying lustrous and transparent phenomenon ", but particulate is owing to self gravitation influences under alternating voltage because in a power frequency period; Add the effect of particulate electric field force; Though have certain acceleration,, cause the particulate flight time not long because the alternating voltage direction changes in the power frequency period; Be difficult to reach the high-pressure conductor surface, so alternating voltage detects problems such as there being the susceptibility deficiency down.And metal particle is under DC voltage, because its direction of an electric field is single, thereby particulate is can the flight time when quickening longer, thereby its bump GIS inside surface has bigger amplitude, and the ultrasonic vibration signal that is produced is also corresponding stronger.
In addition; Alternating voltage can make GIS inner space and insulator surface stored charge when long-term pressurization, electric charge accumulates might influence the insulation of electrical installation performance; Thereby the present invention is directed to above problem, propose to adopt the DC voltage of reversal of poles to detect GIS interior metal particle defects.This method utilizes particulate in static and size motion ultrasonic signal amplitude level; And the existence that particulate is divided in the research of the DC voltage through change in polarity and the ultrasonic signal pool of confirming the above two states of particulate whether, eliminates the influence of the inner residual charge of GIS then through at interval DC voltage in order.
Summary of the invention
The objective of the invention is to solve the practical problems of metal particle defects detection important in the GIS; Mainly the static ultrasonic signal level when moving of particulate is compared through positive polarity and negative polarity DC voltage; All kinds of quantity of obtaining through the laboratory then and the horizontal collection of illustrative plates of metal particle ultrasonic signal of shape carry out the characteristic contrast, thereby judge whether GIS inside exists metal particle.
The present invention realizes through following technical proposal.
Adopt the inner particle detection method of GIS of reversal of poles DC voltage, the present invention is in GIS (Gas Insulated Switchgear, gas insulated combined electrical equipment) internal placement metallicity particle defects; Select to switch UNICOM positive polarity DC voltage through synchronous device control; Be applied to GIS high-pressure side and conductor thereof simultaneously, obtain particulate ultrasonic signal level when static through the ultrasound partial discharge tester, then through rubber hammer hammering GIS shell; The particulate take-off; Ultrasonic signal level when obtaining the particle movement of particulate when positive polarity voltage, relatively before and after test ultrasonic signal level difference, assessment and judge that whether the inner particulate of GIS exists.Synchronous device control choosing is to switch UNICOM negative polarity DC voltage; Obtain the ultrasonic signal level of particulate when static through the ultrasound partial discharge tester; Then through rubber hammer hammering GIS shell, particulate take-off, ultrasonic signal level when obtaining the particle movement of particulate when reverse voltage; Twice measuring-signal level difference relatively, comprehensive last evaluation result assesses jointly and judges that whether the GIS particulate exists.In the GIS test section; Ultrasonic signal horizontal data storehouse before and after the rubber hammer hammering when obtaining line particulate, spherical particle and the combination of multiple quantity (or length) particulate thereof; Relatively obtain typical ultrasonic signal level difference and quantitative criteria thereof under positive polarity and the reversed polarity DC voltage; Thereby there are situation in assessment and judgement particulate, even can assess the particle type and the order of magnitude thereof.Synchronous device control choosing makes the GIS high-pressure side be connected to the positive polarity DC voltage 1 minute to switch; Select then to switch choosing to negative polarity DC voltage 1 minute; So back and forth continue 10 minutes, eliminate applying the space charge that DC voltage causes and the influence of residual charge.
The invention has the beneficial effects as follows: 1) volume is little, portable, is easy to control and operation; 2) be beneficial to the metal particle defective of finding that GIS is inner.
Further set forth content of the present invention below in conjunction with accompanying drawing and instance.
Description of drawings
Fig. 1 reversal of poles DC voltage particle detection method synoptic diagram;
Fig. 2 reversal of poles DC voltage applies synoptic diagram (to 220kVGIS).
Among the figure: 1, pressure regulator low pressure end; 2, pressure regulator high-pressure side; 3, choosing is to switch; 4, ground connection; 5, synchronous device; 6, high-voltage connection; 7, positive polarity dc generator low pressure end; 8, negative polarity dc generator low pressure end; 9, positive polarity dc generator high-pressure side; 10, negative polarity dc generator high-pressure side; 11, switch rotation direction; 12, switch; 13, GIS, 14, line particulate; 15, ball particulate; 16, high-pressure conductor; 17, GIS shell; 18, sonac; 19, preprocessor; 20, signal Processing terminal; 21, rubber hammer.
Embodiment
Adopt the inner particle detection method of GIS of reversal of poles DC voltage, method of the present invention is:
(1) GIS internal placement metallicity particle defects to switch UNICOM positive polarity DC voltage, is applied to GIS high-pressure side and conductor thereof through synchronous device control choosing simultaneously; Obtain particulate ultrasonic signal level when static through the ultrasound partial discharge tester; Then through rubber hammer hammering GIS shell, particulate take-off, ultrasonic signal level when obtaining the particle movement of particulate when positive polarity voltage; Test ultrasonic signal level difference relatively, whether assessment and the inner particulate of judgement GIS exist.
(2) synchronous device control choosing is to switch UNICOM negative polarity DC voltage; Obtain the ultrasonic signal level of particulate when static through the ultrasound partial discharge tester; Then through rubber hammer hammering GIS shell, particulate take-off, ultrasonic signal level when obtaining the particle movement of particulate when reverse voltage; Twice measuring-signal level difference relatively, comprehensive last evaluation result assesses jointly and judges that whether the GIS particulate exists.
(3) in the GIS test section; Ultrasonic signal horizontal data storehouse before and after the rubber hammer hammering when obtaining line particulate, spherical particle and the combination of multiple quantity (or length) particulate thereof; Relatively obtain typical ultrasonic signal level difference and quantitative criteria thereof under positive polarity and the reversed polarity DC voltage; Thereby there are situation in assessment and judgement particulate, even can assess the particle type and the order of magnitude thereof.
(4) synchronous device control choosing makes the GIS high-pressure side be connected to the positive polarity DC voltage 1 minute to switch; Select then to switch choosing to negative polarity DC voltage 1 minute; So back and forth continue 10 minutes, eliminate applying the space charge that DC voltage causes and the influence of residual charge.
See Fig. 1, the figure shows reversal of poles DC voltage particle detection method synoptic diagram.This method at first is to be connected to choosing to switch 3 through pressure regulator high-pressure side 2; Choosing is connected and the different DC voltage of polarization respectively with negative polarity dc generator low pressure end 8 with positive polarity dc generator low pressure end 7 through high-voltage connection 6 to switch 3; High-pressure conductor 16 at GIS 13 applies the positive polarity DC voltage then, and synchronous device 5 control choosings are connected with switch to switch 3 12 same periods; Because line particulate 14 or ball particulate 15 generally remain static, obtain particulate through sonac 18 and produce ultrasonic signal level or noise level when static this moment, then through rubber hammer 21 hammering GIS 13 shells; Make particulate can break away from the viscous force on GIS 13 enclosure interior surface; Thereby take-off, because electric field action makes that particulate can be in GIS 13 inner flights; Thereby constantly back and forth clash into the GIS housing; Thereby produce the ultrasonic vibration signal, these signals that obtained by sonac 18 transfer to preprocessor 19, and preprocessor is connected to signal Processing terminal 20 again; The difference of the ultrasonic signal level of more static by signal Processing terminal 20 then and motion state judges that whether particulate exists.Pass through the difference of the ultrasonic signal level of the static and motion state under the reverse voltage in addition, unite and confirm that whether particulate exists.
See Fig. 2, the figure shows the reversal of poles DC voltage and apply synoptic diagram.Shown among the figure that GIS 13 high-pressure conductors 16 apply positive polarity and reverse voltage replaces time relation; The fundamental purpose of this method is to inject the electric charge of opposed polarity through the voltage of alternation; Eliminate the electric charge effect of accumulation that GIS 13 produces owing to DC voltage in the closed test process, thereby guarantee that GIS 13 insulation ambient conditions keep higher level.
Claims (1)
1. adopt the inner particle detection method of GIS of reversal of poles DC voltage, it is characterized in that this method is:
(1) GIS internal placement metallicity particle defects to switch UNICOM positive polarity DC voltage, is applied to GIS high-pressure side and conductor thereof through synchronous device control choosing simultaneously; Obtain particulate ultrasonic signal level when static through the ultrasound partial discharge tester; Then through rubber hammer hammering GIS shell, particulate take-off, ultrasonic signal level when obtaining the particle movement of particulate when positive polarity voltage; Test ultrasonic signal level difference relatively, whether assessment and the inner particulate of judgement GIS exist;
(2) synchronous device control choosing is to switch UNICOM negative polarity DC voltage; Obtain the ultrasonic signal level of particulate when static through the ultrasound partial discharge tester; Then through rubber hammer hammering GIS shell, particulate take-off, ultrasonic signal level when obtaining the particle movement of particulate when reverse voltage; Twice measuring-signal level difference relatively, comprehensive last evaluation result assesses jointly and judges that whether the GIS particulate exists;
(3) in the GIS test section; Ultrasonic signal horizontal data storehouse before and after the rubber hammer hammering when obtaining line particulate, spherical particle or particulate combination; Relatively obtain typical ultrasonic signal level difference and quantitative criteria thereof under positive polarity and the reversed polarity DC voltage; Thereby there are situation in assessment and judgement particulate, and the particle type and the order of magnitude thereof;
(4) synchronous device control choosing makes the GIS high-pressure side be connected to the positive polarity DC voltage lasting 30s-1 minute to switch; Select then to the switch choosing to continuing 30s-1 minute to the negative polarity DC voltage; Necessarily require strict equating of positive polarity and negative polarity DC voltage duration; So back and forth continue to be no more than 10 minutes, eliminate to apply the space charge that DC voltage causes and the influence of residual charge.
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Cited By (11)
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| CN102928754A (en) * | 2012-11-15 | 2013-02-13 | 云南电力试验研究院（集团）有限公司电力研究院 | Initial movement device for triggering gas insulated switchgear (GIS) equipment defect in local discharge test for electricity |
| CN103941165A (en) * | 2014-04-22 | 2014-07-23 | 中国能源建设集团广东省电力设计研究院 | GIS equipment testing device and method |
| CN105527199A (en) * | 2016-01-25 | 2016-04-27 | 西安交通大学 | Novel inflatable metal particle research device |
| CN105910963A (en) * | 2016-04-12 | 2016-08-31 | 西安交通大学 | Metal particle research method and device based on addition of space charge by third electrode |
| CN107015129A (en) * | 2017-05-08 | 2017-08-04 | 中国南方电网有限责任公司电网技术研究中心 | The detecting system and method for GIS partial discharge characteristic |
| CN107329059A (en) * | 2017-07-19 | 2017-11-07 | 西安交通大学 | Device and method for detecting superimposed voltage of free conductive particles in GIS |
| CN107390066A (en) * | 2017-08-07 | 2017-11-24 | 中国电力科学研究院 | Judge the method and device of gas-insulated transmission line sprayed coating particle movement state |
| CN108435422A (en) * | 2018-03-23 | 2018-08-24 | 太以环境科技（北京）有限公司 | Atmospheric ionization mode selector |
| CN109444680A (en) * | 2018-10-23 | 2019-03-08 | 国网天津市电力公司 | GIS metal particle extent of injury judgment method |
| CN112881871A (en) * | 2021-01-13 | 2021-06-01 | 国网宁夏电力有限公司电力科学研究院 | Detection method and detection system for metal particles in GIS equipment |
| CN113189452A (en) * | 2021-03-11 | 2021-07-30 | 西安交通大学 | GIS latent metal particle detection device based on external vibration excitation |
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Cited By (17)
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| CN102928754B (en) * | 2012-11-15 | 2015-06-03 | 云南电力试验研究院（集团）有限公司电力研究院 | Initial movement device for triggering gas insulated switchgear (GIS) equipment defect in local discharge test for electricity |
| CN102928754A (en) * | 2012-11-15 | 2013-02-13 | 云南电力试验研究院（集团）有限公司电力研究院 | Initial movement device for triggering gas insulated switchgear (GIS) equipment defect in local discharge test for electricity |
| CN103941165A (en) * | 2014-04-22 | 2014-07-23 | 中国能源建设集团广东省电力设计研究院 | GIS equipment testing device and method |
| CN105527199B (en) * | 2016-01-25 | 2018-06-29 | 西安交通大学 | Novel inflatable metal particle research device |
| CN105527199A (en) * | 2016-01-25 | 2016-04-27 | 西安交通大学 | Novel inflatable metal particle research device |
| CN105910963A (en) * | 2016-04-12 | 2016-08-31 | 西安交通大学 | Metal particle research method and device based on addition of space charge by third electrode |
| CN105910963B (en) * | 2016-04-12 | 2018-12-04 | 西安交通大学 | Metal particle research method and device based on addition of space charge by third electrode |
| CN107015129A (en) * | 2017-05-08 | 2017-08-04 | 中国南方电网有限责任公司电网技术研究中心 | The detecting system and method for GIS partial discharge characteristic |
| CN107329059A (en) * | 2017-07-19 | 2017-11-07 | 西安交通大学 | Device and method for detecting superimposed voltage of free conductive particles in GIS |
| CN107390066A (en) * | 2017-08-07 | 2017-11-24 | 中国电力科学研究院 | Judge the method and device of gas-insulated transmission line sprayed coating particle movement state |
| CN107390066B (en) * | 2017-08-07 | 2020-09-11 | 中国电力科学研究院 | Method and device for judging motion state of particles of spraying layer of gas-insulated power transmission line |
| CN108435422A (en) * | 2018-03-23 | 2018-08-24 | 太以环境科技（北京）有限公司 | Atmospheric ionization mode selector |
| CN108435422B (en) * | 2018-03-23 | 2024-06-07 | 太以环境科技（北京）有限公司 | Atmospheric ionization mode selector |
| CN109444680A (en) * | 2018-10-23 | 2019-03-08 | 国网天津市电力公司 | GIS metal particle extent of injury judgment method |
| CN112881871A (en) * | 2021-01-13 | 2021-06-01 | 国网宁夏电力有限公司电力科学研究院 | Detection method and detection system for metal particles in GIS equipment |
| CN113189452A (en) * | 2021-03-11 | 2021-07-30 | 西安交通大学 | GIS latent metal particle detection device based on external vibration excitation |
| CN113189452B (en) * | 2021-03-11 | 2022-10-28 | 西安交通大学 | GIS latent metal particle detection device based on external vibration excitation |
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