CN104459529A - Double-loop-current testing method for mechanical characteristic test of transformer substation high-voltage circuit breaker - Google Patents
Double-loop-current testing method for mechanical characteristic test of transformer substation high-voltage circuit breaker Download PDFInfo
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Abstract
The invention discloses a double-loop-current testing method for the mechanical characteristic test of a transformer substation high-voltage circuit breaker. The problem that when carrying out tests on site, a tester is faced with an induced electricity threat is solved. The double-loop-current testing method is characterized in that a grounding knife-switch (1) and a grounding knife-switch (2) on the two sides of the high-voltage circuit breaker are switched on, the two ends of the high-voltage circuit breaker are grounded, a signal wire A, a signal wire B and a signal wire C of an instrument are connected with lower ports of the grounding knife-switch (2), three grounding wires of the instrument are connected with lower ports of the grounding knife-switch (1), and a grounding terminal of the instrument is grounded; the instrument is operated to output I+, U+, I- and U- into a loop to form two loops, and the resistance changes in the switch-off and switch-on processes of the high-voltage circuit breaker are tested to obtain mechanical characteristic data of the high-voltage circuit breaker. The accurate data of the high-voltage circuit breaker can be measured effectively, it is avoided that the tester climbs up to connect the testing signal wires, and the induced electricity threat and induced electricity interference are effectively eliminated; the testing time is shortened, the working efficiency is greatly improved, electricity can be supplied as soon as possible, and therefore the double-loop-current testing method has huge economic value.
Description
Technical field
What the present invention relates to is a kind of power test measuring technique, relates to the new-type method of testing of the acting characteristic test of transformer station's inner high voltage isolating switch or rather.
Background technology
In recent years, along with the development of electric system, electrical network is more and more intensive, and electric pressure is more and more higher, causes transformer station's induced electricity potential threat to increase, and is faced with very strong induced electricity and threatens when transformer station's testing crew is done experiment at the scene.Primary cut-out, as the important equipment of transformer station, needs often to carry out conventional test, and the induced electricity that testing crew faces threatens also increasing.
Traditional method of testing is the signal sampling line of primary cut-out one end ground connection, another termination testing apparatus.Such method of testing just needs testing crew and carries out high-altitude clamp work, and on top A, B, C three-phase of primary cut-out, fracture wiring place connects signal sampling line, and under A, B, C three-phase, fracture connects the negative line of signal.If testing crew adjacent spaces when high-altitude wiring is run, or test primary cut-out side disconnecting link does not get togather with age, all testing crew can be placed oneself in the midst of in strong induced electricity threat.Along with this threat of development of power construction is increasing.
From the current mode of connection, at present primarily of two kinds of modes, a kind of is that the high-altitude clamping pliers using epoxy polyester to make carries out operation, and another adopts high-altitude lift truck.Although first method is simply light, there is great potential safety hazard, when testing ground wind-force larger especially cold weather time, or when testing crew fatigue, when testing crew lift pole carry out wiring time, be just not easy in hand, be easy to swing to charged interval.Adopted operation in this way in recent years, the thing that testing crew injures and deaths occur because wind-force swings to greatly charged interval also occurs for several times.The method of the second is that testing crew is delivered to high-altitude by high-altitude lift truck, manually carries out operation.This mode Problems existing is: lift truck volume ratio is comparatively large, and some intervals are smaller, and lift truck is not easy to enter; In operation, very high to the technical requirement of driver, and the test situation at scene, interval is smaller, when work high above the ground, careless slightly, instruction carriage in operating process will occur encounter or break the situation of field apparatus, causes huge economic loss.
Generally, as shown in Figure 1, be connected to grounding switch 1 on the left of primary cut-out, right side is connected to grounding switch 2 to transformer station's primary cut-out equipment connection situation, and the height of primary cut-out, for 220KV, is about 8 meters.When tradition does mechanical characteristic of high-voltage circuit breaker test, the conventional mode of connection is that in Fig. 1, grounding switch 1 and 2 all closes, and on such primary cut-out, fracture and lower fracture have all accessed geodetic network, are in same electromotive force position.Then according to shown in Fig. 2, on isolating switch A, B, C three-phase, fracture draws yellow, green, red three signal testing lines access breaker mechanic property testing tool, under A, B, C three-phase, the thin black line short circuit of fracture gets up, the ground terminal of access breaker mechanic property testing tool, then grounding switch 1 is opened, operating instrument is tested, and test obtains the time data of mechanical characteristic of high-voltage circuit breaker test figure: opening time, the separating brake time same period, closing time, the combined floodgate time same period.
There are two kinds of drawbacks in this mode of connection, the first, primary cut-out grounding switch 1 is because of test needs, by be closed into open time, upper fracture has just been with induced charge, induced charge has been introduced into again instrument by yellow, green, red three lines, once the loose contact of instrument bleed-off circuit, and the high voltage of what people went operating instrument directly to contact is exactly induced charge, people can directly injure or beat and fly by this situation high voltage, abnormally dangerous.The second, primary cut-out and grounding switch run throughout the year out of doors, expose to wind and rain, surface is often oxidized, dirt in attachment, and we are in the process of doing experiment, need close grounding switch 1 and grounding switch 2, if grounding switch 1 or grounding switch 2 are because of oxidation or dirt, really do not close, that testing crew climbs 8 meters of incision positions to this situation when going to connect Huang, green, red three signal wires, direct contact be exactly the high voltage of induced charge, abnormally dangerous.
Summary of the invention
The object of the invention is to overcome the double loop method of testing that the deficiencies in the prior art provide the mechanical characteristic of high-voltage circuit breaker test of a kind of transformer station
,the time data of test transformer station mechanical characteristic of high-voltage circuit breaker test, is judged by the change of resistance in primary cut-out separating brake, making process, obtains the opening time of primary cut-out, separating brake same period, closing time, combined floodgate same period.
Double loop method of testing of the present invention is such:
1, the grounding switch 1 and 2 of primary cut-out both sides is all closed, fracture and lower fracture access geodetic network on primary cut-out;
2, signal wire A, B, C of instrument connect the lower port of grounding switch 2, and three ground wires of instrument connect the lower port of grounding switch 1, instrument ground terminal ground;
3, operating instrument exports I+, U+, I-, U-and forms two loops to loop, the voltage U that instrument exports+, U-forms circulation I, I+, I-formation circulation II that instrument constant current source exports;
4, the change of resistance in testing high voltage breaker open operation, making process, obtains the time data of mechanical characteristic of high-voltage circuit breaker test figure: opening time, separating brake same period, closing time, combined floodgate same period.
The principle of double loop method of testing of the present invention is:
When the complete operating instrument of wiring is tested, what first test operated is separating brake, before separating brake, namely the grounding switch 1 and 2 of primary cut-out is all closed, instrument internal big current working power is to wiring loop output voltage and electric current, and at this moment the equivalent resistance in loop is the parallel resistance resistance of contact resistance in primary cut-out fracture and geodetic network's stake resistance; After separating brake, primary cut-out rupture portion circuit equals to be disconnected, the resistance in whole loop only has the stake resistance of geodetic network, the change of the resistance so before and after separating brake just can be measured and be obtained opening time, separating brake contemporaneous data, wherein, separating brake contemporaneous data is the difference of the minimum and maximum value of three-phase opening time A/B/C.
In like manner, in making process, the change of resistance is just in time contrary with separating brake process, and the resistance of combined floodgate front loop only has the contact resistance of geodetic network, is the parallel resistance resistance of contact resistance and geodetic network's contact resistance in primary cut-out fracture after closing a floodgate.Closing time, combined floodgate contemporaneous data is obtained by the measure of the change of the front and back resistance that closes a floodgate.
Beneficial effect of the present invention: the present invention can record the precise information of primary cut-out effectively; The new mode of connection avoids the fracture that testing crew climbs to 8 meters high and goes to connect test signal line, protects testing crew; New mode of connection carries out when primary cut-out both sides grounding switch combined floodgate ground connection, effectively removes induced electricity and threaten and induced electricity interference; Present invention reduces the experiment work time, greatly improve work efficiency, comparison tradition climbs to the mode of 8 meters of high-altitude wirings, can shorten the test duration of 2/3rds, power early, can produce huge economic worth for electric system.
Accompanying drawing explanation
Fig. 1 is present transformer station primary cut-out connection device schematic diagram.
Fig. 2 is the wiring diagram of traditional mechanical characteristic of high-voltage circuit breaker test apparatus.
Fig. 3 is wiring diagram of the present invention.
Fig. 4 is the equivalent resistance schematic diagram of primary cut-out of the present invention at separating brake front loop.
Fig. 5 is the equivalent resistance schematic diagram in primary cut-out of the present invention loop after separating brake.
Fig. 6 is enforcement figure of the present invention.
Embodiment
Below in conjunction with accompanying drawing, the present invention is further illustrated.
As shown in Figure 3, signal wire A, B, C of instrument connect the lower port of grounding switch 2, and three ground wires of instrument connect the lower port of grounding switch 1, instrument ground terminal ground.
As shown in Figure 6, the switch of switch arc-chutes represents the fracture of primary cut-out, ground connection equivalent resistance R1 represents the stake resistance of grounding switch 1, ground connection equivalent resistance R2 represents the stake resistance of grounding switch 2, and instrument exports I+, U+, I-, U-to loop, forms two loops, the voltage U that instrument exports+, U-forms circulation I, I+, I-that instrument constant current source exports form circulation II, i.e. double loop method of testing of the present invention, namely four line current voltage methods.
The effect of circulation 1 obtains the large probable value needed for test, when primary cut-out is in separating brake, making process, side equipment live, due to electromagnetic interference (EMI), induction current disturbed test data can be there are in circuit, make data inaccurate, the data obtained can only be accurate to 0.5ms, and testing requirements data will be accurate to 0.1ms.The effect of circulation 2 is exactly the exact value obtaining test.
Thered is provided the constant current source being not less than 10A by instrument, I+ output, I-input, big current has flooded the interference that induced electricity brings, and when primary cut-out disconnects, as shown in Figure 5, the resistance in loop is ground connection equivalent resistance and geodetic network's resistance; When primary cut-out closes, as shown in Figure 4, the equivalent resistance in loop is the contact resistance of switch and the parallel resistance value of ground connection equivalent resistance, whole change procedure obtains data respectively by circulation 1 and circulation 2, calculate, remove interfering data, thus obtain primary cut-out closing time, close a floodgate the same period, opening time, separating brake same period.Double loop method of testing data the are accurate to rank of 0.05ms, accurate data contribute to the hidden failure analyzing primary cut-out very much.
Claims (1)
1. a double loop method of testing for transformer station's mechanical characteristic of high-voltage circuit breaker test, is characterized in that:
(1) grounding switch 1 and 2 of primary cut-out both sides is all closed, fracture and lower fracture access geodetic network on primary cut-out;
(2) signal wire A, B, C of instrument connect the lower port of grounding switch 2, and three ground wires of instrument connect the lower port of grounding switch 1, instrument ground terminal ground;
(3) operating instrument exports I+, U+, I-, U-and forms two loops to loop, the voltage U that instrument exports+, U-forms circulation I, I+, I-formation circulation II that instrument constant current source exports;
(4) change of resistance in testing high voltage breaker open operation, making process, obtains the time data of mechanical characteristic of high-voltage circuit breaker test figure: opening time, separating brake same period, closing time, combined floodgate same period.
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| CN201410794819.XA CN104459529B (en) | 2014-12-21 | 2014-12-21 | The double loop method of testing of transformer station's mechanical characteristic of high-voltage circuit breaker experiment |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| US20150198667A1 (en) * | 2014-01-16 | 2015-07-16 | Vanguard Instruments Company, Inc. | Dual ground breaker testing system |
| CN105203947A (en) * | 2015-08-27 | 2015-12-30 | 国网安徽省电力公司阜阳供电公司 | Performance characteristic testing method of high-voltage circuit breaker |
| CN105866667A (en) * | 2016-03-31 | 2016-08-17 | 国家电网公司 | Loop resistance test method for two-terminal-grounding circuit breaker |
| CN106249142A (en) * | 2016-10-18 | 2016-12-21 | 国网江苏省电力公司电力科学研究院 | A kind of extra-high voltage switch intelligent device for measuring |
| CN106959415A (en) * | 2017-03-21 | 2017-07-18 | 武汉市欧睿科技有限公司 | High voltage switch dynamic characteristics method of testing based on bicyclic electric current |
| CN107015106A (en) * | 2017-06-02 | 2017-08-04 | 广州思壮电气股份有限公司 | Ground state detection unit, earthing or grounding means and ground state detection method |
| CN107221924A (en) * | 2017-07-31 | 2017-09-29 | 江苏省电力试验研究院有限公司 | A kind of primary cut-out fracture induced voltage suppression circuit, method and test system |
| CN108490348A (en) * | 2018-05-25 | 2018-09-04 | 广东电网有限责任公司 | Method, device and system for testing performance of circuit breaker with double ground knives |
| CN108594019A (en) * | 2018-03-19 | 2018-09-28 | 广东电网有限责任公司中山供电局 | A kind of GIS loop resistance test device and method for not tearing earthing bar open |
| CN108845251A (en) * | 2018-06-26 | 2018-11-20 | 国网黑龙江省电力有限公司绥化供电公司 | The GIS combination electric appliance comprehensive tester and test method of double-station disconnecting link |
| CN108918971A (en) * | 2018-03-29 | 2018-11-30 | 浙江长兴笛卡尔科技有限公司 | Calculate the method and device of dynamic equivalent internal resistance |
| CN109901063A (en) * | 2019-03-11 | 2019-06-18 | 中国长江电力股份有限公司 | A kind of GIS separate unit power failure of breaker time response measurement method |
| CN113325305A (en) * | 2021-06-03 | 2021-08-31 | 贵州电网有限责任公司 | 500kV circuit breaker high-voltage electrical test wiring device and use method thereof |
| CN113835027A (en) * | 2021-09-23 | 2021-12-24 | 广东电网有限责任公司 | Dynamic characteristic testing device and method for circuit breaker |
| CN114325114A (en) * | 2021-11-29 | 2022-04-12 | 云南电网有限责任公司昆明供电局 | Double-end grounding loop resistance testing method of disassembly-free grounding wire |
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Cited By (20)
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| US20150198667A1 (en) * | 2014-01-16 | 2015-07-16 | Vanguard Instruments Company, Inc. | Dual ground breaker testing system |
| US9551752B2 (en) * | 2014-01-16 | 2017-01-24 | Vanguard Instruments Company, Inc. | Dual ground breaker testing system |
| CN105203947A (en) * | 2015-08-27 | 2015-12-30 | 国网安徽省电力公司阜阳供电公司 | Performance characteristic testing method of high-voltage circuit breaker |
| CN105866667A (en) * | 2016-03-31 | 2016-08-17 | 国家电网公司 | Loop resistance test method for two-terminal-grounding circuit breaker |
| CN105866667B (en) * | 2016-03-31 | 2018-12-04 | 国家电网公司 | A kind of loop resistance test method of two sides earth breaker |
| CN106249142A (en) * | 2016-10-18 | 2016-12-21 | 国网江苏省电力公司电力科学研究院 | A kind of extra-high voltage switch intelligent device for measuring |
| CN106959415A (en) * | 2017-03-21 | 2017-07-18 | 武汉市欧睿科技有限公司 | High voltage switch dynamic characteristics method of testing based on bicyclic electric current |
| CN107015106A (en) * | 2017-06-02 | 2017-08-04 | 广州思壮电气股份有限公司 | Ground state detection unit, earthing or grounding means and ground state detection method |
| CN107221924A (en) * | 2017-07-31 | 2017-09-29 | 江苏省电力试验研究院有限公司 | A kind of primary cut-out fracture induced voltage suppression circuit, method and test system |
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| CN108918971B (en) * | 2018-03-29 | 2022-04-19 | 浙江长兴笛卡尔科技有限公司 | Method and device for calculating dynamic equivalent internal resistance |
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| CN108845251A (en) * | 2018-06-26 | 2018-11-20 | 国网黑龙江省电力有限公司绥化供电公司 | The GIS combination electric appliance comprehensive tester and test method of double-station disconnecting link |
| CN109901063B (en) * | 2019-03-11 | 2021-05-04 | 中国长江电力股份有限公司 | Method for measuring power failure time characteristic of GIS single circuit breaker |
| CN109901063A (en) * | 2019-03-11 | 2019-06-18 | 中国长江电力股份有限公司 | A kind of GIS separate unit power failure of breaker time response measurement method |
| CN113325305A (en) * | 2021-06-03 | 2021-08-31 | 贵州电网有限责任公司 | 500kV circuit breaker high-voltage electrical test wiring device and use method thereof |
| CN113835027A (en) * | 2021-09-23 | 2021-12-24 | 广东电网有限责任公司 | Dynamic characteristic testing device and method for circuit breaker |
| CN114325114A (en) * | 2021-11-29 | 2022-04-12 | 云南电网有限责任公司昆明供电局 | Double-end grounding loop resistance testing method of disassembly-free grounding wire |
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