CN102221652A - Method and device for testing 500kV metal oxide arrester - Google Patents

Method and device for testing 500kV metal oxide arrester Download PDF

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Publication number
CN102221652A
CN102221652A CN2011100715782A CN201110071578A CN102221652A CN 102221652 A CN102221652 A CN 102221652A CN 2011100715782 A CN2011100715782 A CN 2011100715782A CN 201110071578 A CN201110071578 A CN 201110071578A CN 102221652 A CN102221652 A CN 102221652A
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joint
test
voltage
zinc
valve block
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张晓娜
丁恩强
伏忠旺
李越鹏
王钢
刘淼
齐志铭
杨越
孟也暄
姜修平
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MAINTENANCE BRANCH LIAONING POWER CO Ltd
State Grid Corp of China SGCC
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AN'SHAN ULTRAHIGH PRESSURE BRANCH OF LIAONING ELECTRIC POWER Co Ltd
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Abstract

The invention relates to a method and a device for testing a 500kV metal oxide arrester. The method and the device are characterized in that: in a testing process, an upper-segment high tension lead is reserved, a line side grounding knifeswitch is switched on as a testing ground wire, and the upper-segment top of a metal oxide valve plate is grounded to eliminate electrostatic interference; each valve plate forms a testing loop with a DC high voltage generator and the ground respectively; a microampere meter is connected in series to the ground wire; and in the testing of a middle-segment valve plate, another microampere meter and a low tension arrester group are connected in series between a lower-segment valve plate and the ground. Compared with the prior art, the invention has the advantages of: 1) not requiring aerial work for connecting and disconnecting the high tension lead; 2) simplifying operations by utilizing the grounding knifeswitch as the testing ground wire; and 3) eliminating the influence of high voltage static electricity on test data and ensuring the accuracy of the test data.

Description

A kind of test method and device of testing the 500kV Zinc-Oxide Arrester
Technical field
The present invention relates to electric system 500kV transformer station field, relate in particular to a kind of test method and device of the 500kV of test Zinc-Oxide Arrester.
Background technology
Zinc-Oxide Arrester (being called for short MOA) is the major equipment of protection power system safety and stability operation, MOA is equivalent to the non-linear resistance that one 2~3 joint is connected in series, utilize the good non-linear volt-ampere characteristic of zinc paste to play earial drainage and the effect of cut-offfing, when normal working voltage, flow through the electric current minimum (microampere or milliampere level) of lightning arrester; When the superpotential effect, resistance sharply descends, and the superpotential energy of releasing reaches the effect of protection.
About 12 meters of 500kV MOA top high-voltage lead pitch ground, line side are provided with ground connection disconnecting link (during power down mode ground connection disconnecting link closing position), ground connection behind the discharged in series counter below the MOA, and discharge counter is used for writing down lightning-arrest action frequency.When electrical network is struck by lightning; when voltage is elevated to lightning arrester specified action voltage (generally be set at system voltage 1.15 times), the lightning arrester action discharges the superpotential load; the amplitude limitation of line voltage under certain level, is protected apparatus insulatedly not to be damaged.MOA can also limit the internal overvoltage that a part is caused by operation except the restriction Lightning Over-voltage.
Electric system is normally in service, and the routine test project of Zinc-Oxide Arrester is had: 1) insulation measurement, determining whether lightning arrester makes moist, can also check for what there was a big fuse inside whether internal fuse is intact; Critical operation voltage U1mA when 2) measuring direct current 1mA checks mainly whether the valve block insulation is good, determines whether its performance meets the requirements; Leakage current when 3) measuring direct current 75%U1mA; whether purpose is to detect to allow working current up to specification for a long time; " rules " regulation; leakage current values under the 75%U1mA should be not more than 50 μ A; every index of having only MOA is all in acceptability limit; can guarantee that just it is functional, thus the safety of protection electrical equipment.
Testing crew was when carrying out the test of 500kV Zinc-Oxide Arrester in the past, must remove high-voltage connection, need 5~6 maintainers to utilize bucket arm vehicle, crane work high above the ground, because adjacent spaces or top bus are charged, cause lead-in wire to have several kilovolts even volt electrostatic potential up to ten thousand, the operating personnel is subject to electric shock; During last joint ground connection, need a testing crew and lift insulating bar and hang and provide ground wire for oneself, operation easier is big, the time is long, because each work post cross-operation and frequently disconnect high-voltage connection also constitutes certain potential safety hazard to personal and equipment.In addition, because the influence of electrostatic potential causes measuring error, and test figure is inaccurate, erroneous judgement is disconnected easily behind the dismounting high-voltage connection.
In the conventionally test test, to go up the joint high-voltage connection earlier removes, last joint test line is seen Fig. 2-1, joint test line sees that Fig. 2-2, middle joint test line see Fig. 2-3 down, and wherein R1, R2, R3 are respectively the equivalent resistance of every joint MOA valve block, insulate between MOA base and the ground.High voltage direct current generator applies the DC voltage of 200kv ± 5% respectively to every joint MOA valve block one end, ground connection constitutes test loop behind the MOA valve block other end series connection microampere meter, measure MOA respectively and respectively save Leakage Current under critical operation voltage U1mA and the 75%U1mA direct current, especially the joint test is to test as not tearing high-voltage connection open in.
Summary of the invention
The test method and the device that the purpose of this invention is to provide a kind of 500kV of test Zinc-Oxide Arrester, overcome the deficiencies in the prior art, realize that do not tear high-voltage connection open finishes 500kV Zinc-Oxide Arrester testing experiment, test figure is accurate, for the safe operation of electric system provides reliable assurance.
For solving the problems of the technologies described above, technical scheme of the present invention is:
A kind of test method of testing the 500kV Zinc-Oxide Arrester keeps in the process of the test and goes up the joint high-voltage connection, and the line side ground connection disconnecting link that closes is eliminated electrostatic interference as the test ground wire, and its concrete operations step is as follows:
1) at first goes up the joint test, the microampere meter of between lightning arrester line side ground connection disconnecting link and ground, connecting, utilize high voltage direct current generator on the Zinc-Oxide Arrester joint and middle joint between contact apply DC voltage, when microampere meter numerical value reaches 1mA, reach the critical operation voltage of 200kv ± 5%, because middle joint and joint zinc oxide valve plate series connection down, its impedance is much larger than last joint impedance, so, when last joint reaches the action of critical operation voltage, in joint and down joint be high-impedance state and be failure to actuate the leakage current when critical operation voltage U1mA of joint and 75%U1mA gone up in record respectively;
2) descend the joint test then, with the Zinc-Oxide Arrester valve block down the discharge counter between joint and the ground pull down and replace to microampere meter, utilize high voltage direct current generator in the Zinc-Oxide Arrester valve block, to save and down between the joint contact apply the DC voltage of 200kv ± 5%, because last joint and the series connection of middle joint valve block, its impedance much larger than under save impedance, so, when Zinc-Oxide Arrester valve block when down joint reaches critical operation voltage action, last joint and middle joint are high-impedance state is failure to actuate, the leakage current when noting critical operation voltage U1mA of joint and 75%U1mA respectively;
3) carry out middle joint test at last, microampere meter one ground connection afterwards of earlier contact between joint on the valve block and the middle joint being connected, and then with the ground connection after microampere meter two and the low voltage surge arrester group of connecting successively of joint under the valve block, with high voltage direct current generator in valve block, save and down between the joint contact apply DC voltage, when microampere meter one shows that electric current reaches 1mA, voltage on the middle joint valve block reaches the critical operation voltage of 200kv ± 5%, in pressure process, to monitor the microampere meter two that string saves simultaneously and can not surpass 1mA under valve block, in order to avoid the high voltage direct current generator overload, the leakage current when saving critical operation voltage U1mA and 75%U1mA in the record respectively.
A kind of test unit of testing the 500kV Zinc-Oxide Arrester, comprise microampere meter, line side ground connection disconnecting link, line side ground connection disconnecting link is for closing the position, joint top ground connection on the zinc oxide valve plate, each saves zinc oxide valve plate and constitutes test loop respectively and between high voltage direct current generator and the ground, and microampere meter is connected on the ground wire.
In joint valve block when test, also connect between following joint valve block and the ground another piece microampere meter and a low voltage surge arrester group.
The U1mA of described low voltage surge arrester group is 5kV ± 5%, is in series by four lightning arresters, and the U1mA of single lightning arrester is 1.25kV ± 5%.
Compared with prior art, the invention has the beneficial effects as follows:
1) do not need work high above the ground to disconnect high-voltage connection, saved the expense of work high above the ground vehicle, avoided frequently disconnecting damage and the high-altitude falling risk that high-voltage connection causes equipment.
2) utilize the at interval line-to-ground disconnecting link ground wire of doing experiment of lightning arrester, simplified control saves manpower and time, and has improved work efficiency.
3) ground connection disconnecting link ground connection is good, has avoided the high-pressure electrostatic injury, has eliminated the influence of high-pressure electrostatic to test data, and the test figure accuracy is met the demands, and has avoided erroneous judgement disconnected, guarantees that equipment " health " puts into operation, and guarantees power supply reliability, and equipment failure rate is zero.
Description of drawings
Fig. 1-the 1st, the present invention test the wiring schematic diagram of joint;
Fig. 1-2 is the wiring schematic diagram that the present invention tests down joint;
Fig. 1-the 3rd, the wiring schematic diagram of joint during the present invention tests;
Fig. 2-the 1st, the wiring schematic diagram that saves on the conventionally test;
Fig. 2-the 2nd, conventionally test is the wiring schematic diagram of joint down;
Fig. 2-the 3rd, the wiring schematic diagram that saves in the conventionally test.
Embodiment
Below in conjunction with accompanying drawing the specific embodiment of the present invention is described further:
A kind of test method of testing the 500kV Zinc-Oxide Arrester of the present invention keeps in process of the test and saves high-voltage connection, and the line side ground connection disconnecting link that closes is eliminated electrostatic interference as the test ground wire, and its concrete operations step is as follows:
1) see Fig. 1-1, at first go up joint test, the microampere meter of between lightning arrester line side ground connection disconnecting link and ground, connecting, utilize high voltage direct current generator on the Zinc-Oxide Arrester joint and middle joint between contact apply DC voltage, when microampere meter numerical value reaches 1mA, apply voltage and can reach 200kv ± 5%, because middle joint and joint zinc oxide valve plate series connection down, its impedance is much larger than last joint impedance, so, when last joint reaches the action of critical operation voltage, in joint and down joint be high-impedance state and be failure to actuate the leakage current when critical operation voltage U1mA of joint and 75%U1mA gone up in record respectively;
2) see Fig. 1-2, descend the joint test then, with the Zinc-Oxide Arrester valve block down the discharge counter between joint and the ground pull down and replace to microampere meter, utilize high voltage direct current generator in the Zinc-Oxide Arrester valve block, to save and down between the joint contact apply the DC voltage of about 200kv ± 5%, because last joint and the series connection of middle joint valve block, its impedance much larger than under save impedance, so, when Zinc-Oxide Arrester valve block when down joint reaches critical operation voltage action, last joint and middle joint are high-impedance state is failure to actuate, the leakage current when noting critical operation voltage U1mA of joint and 75%U1mA respectively;
3) see Fig. 1-3, joint test in carrying out at last, microampere meter one ground connection afterwards of earlier contact between joint on the valve block and the middle joint being connected, and then with the ground connection after microampere meter two and the low voltage surge arrester group of connecting successively of joint under the valve block, the U1mA of low voltage surge arrester group is 5kV ± 5%, is in series by four lightning arresters, and the U1mA of single lightning arrester is 1.25kV ± 5%, its model is the y3w0.22kV lightning arrester, and lightning arrester factory in Dalian produces.
With high voltage direct current generator in valve block, save and down between the joint contact apply DC voltage, when microampere meter one shows that electric current reaches 1mA, voltage on the middle joint valve block reaches the about 200kv of critical operation voltage ± 5%, in pressure process, to monitor the microampere meter two that string saves simultaneously and can not surpass 1mA under valve block, in order to avoid high voltage direct current generator overload, because auxiliary low voltage surge arrester group that the middle joint of joint is many down, under save the Zinc-Oxide Arrester valve block can delayed action, and middle joint regular event, thereby reached our test objective, the Leakage Current when saving critical operation voltage U1mA and 75%U1mA in the record respectively.
Do not tear high-voltage connection open in the past, do experiment for middle joint, by removing the discharge register, in the low voltage surge arrester group that serial connection is in series by four lightning arresters between joint and the ground down, purpose is to improve the critical operation voltage value of joint down, following festival-gathering delayed action, and middle joint regular event, thus reach test objective.In addition, the low voltage surge arrester group also plays protection MOA base insulation not impaired effect in process of the test.
Adopt the inventive method respectively to the going up joint, middle joint, save and test down of 500kV Zinc-Oxide Arrester A, B, C three-phase, test figure result such as following table 1, to tear the data that the high-voltage connection method records open basic identical with routine.
Table 1
Figure BDA0000051740920000041
For guaranteeing test mass and safety, according to the relevant regulations of Liaoning Power and " power transmission and transformation equipment state overhauling testing regulations " Q/GDW168-2008, " power equipment preventive trial rules " and at the correlation test method of Zinc-Oxide Arrester, should note following item:
1) accurately read U1mA, because the volt-ampere characteristic of oxide lightning arrester, when leakage current during greater than 200 μ A, along with the rising of output voltage, electric current can sharply increase, so should rationally control the rate of rise, it is too fast to prevent to boost, and electric current is uprushed, and surpasses 1mA.
2) prevent the influence of surface leakage current, should be before the test with the surperficial wiped clean of MOA.Microampere meter in the test and high-voltage connection should use shielded conductor.
3) influence of temperature, the temperature of test specimen should not be lower than+and 5 ℃, open field test should be carried out at good weather, test under the temperature conditions by the rules regulation, otherwise low, too high excessively temperature all can influence test findings as far as possible.
4) influence of humidity, because relative humidity also can exert an influence to test result, humidity is excessive, can cause leakage current to increase severely, open field test should be carried out at good weather, and air humidity generally is not higher than 80%, for ease of analyzing, should write down relative humidity during test.
5) after the off-test, reply test specimen and the capacitance type equipment that has a power failure on every side thereof fully discharge, and prevent to cause the injury of personnel's electrification.
6) do not remove in the high-voltage connection method test process in use, compare gap with test figure and manufacturer data in the past when big if find test figure, should carefully get rid of factors such as environment, temperature, humidity, shielding, the rate of rise earlier, in case of necessity, dismountable high-voltage connection is tested lightning arrester, conscientious contrast test data.

Claims (4)

1. a test method of testing the 500kV Zinc-Oxide Arrester is characterized in that, keeps in the process of the test to go up the joint high-voltage connection, and the line side ground connection disconnecting link that closes is eliminated electrostatic interference as the test ground wire, and its concrete operations step is as follows:
1) at first goes up the joint test, the microampere meter of between lightning arrester line side ground connection disconnecting link and ground, connecting, utilize high voltage direct current generator on the Zinc-Oxide Arrester joint and middle joint between contact apply DC voltage, when microampere meter numerical value reaches 1mA, reach the critical operation voltage of 200kv ± 5%, because middle joint and joint zinc oxide valve plate series connection down, its impedance is much larger than last joint impedance, so, when last joint reaches the action of critical operation voltage, in joint and down joint be high-impedance state and be failure to actuate the leakage current when critical operation voltage U1mA of joint and 75%U1mA gone up in record respectively;
2) descend the joint test then, with the Zinc-Oxide Arrester valve block down the discharge counter between joint and the ground pull down and replace to microampere meter, utilize high voltage direct current generator in the Zinc-Oxide Arrester valve block, to save and down between the joint contact apply the DC voltage of 200kv ± 5%, because last joint and the series connection of middle joint valve block, its impedance much larger than under save impedance, so, when Zinc-Oxide Arrester valve block when down joint reaches critical operation voltage action, last joint and middle joint are high-impedance state is failure to actuate, the leakage current when noting critical operation voltage U1mA of joint and 75%U1mA respectively;
3) carry out middle joint test at last, microampere meter one ground connection afterwards of earlier contact between joint on the valve block and the middle joint being connected, and then with the ground connection after microampere meter two and the low voltage surge arrester group of connecting successively of joint under the valve block, with high voltage direct current generator in valve block, save and down between the joint contact apply DC voltage, when microampere meter one shows that electric current reaches 1mA, voltage on the middle joint valve block reaches the critical operation voltage of 200kv ± 5%, in pressure process, to monitor the microampere meter two that string saves simultaneously and can not surpass 1mA under valve block, in order to avoid the high voltage direct current generator overload, the leakage current when saving critical operation voltage U1mA and 75%U1mA in the record respectively.
2. test unit of testing the 500kV Zinc-Oxide Arrester, comprise microampere meter, line side ground connection disconnecting link, it is characterized in that, line side ground connection disconnecting link is for closing the position, joint top ground connection on the zinc oxide valve plate, each saves zinc oxide valve plate and constitutes test loop respectively and between high voltage direct current generator and the ground, and microampere meter is connected on the ground wire.
3. a kind of test unit of testing the 500kV Zinc-Oxide Arrester according to claim 2 is characterized in that, during the test of middle joint valve block, and also connect between following joint valve block and the ground another piece microampere meter and a low voltage surge arrester group.
4. a kind of test unit of testing the 500kV Zinc-Oxide Arrester according to claim 3 is characterized in that the U1mA of described low voltage surge arrester group is 5kV ± 5%, is in series by four lightning arresters, and the U1mA of single lightning arrester is 1.25kV ± 5%.
CN2011100715782A 2011-03-23 2011-03-23 Method and device for testing 500kV metal oxide arrester Pending CN102221652A (en)

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CN102692581A (en) * 2012-06-19 2012-09-26 国电大渡河检修安装有限公司 Current leakage test method for lightning arrestor
CN102901894A (en) * 2012-09-29 2013-01-30 辽宁省电力有限公司检修分公司 Test method and device for testing 500kV zinc oxide arrester
CN102928646A (en) * 2012-10-24 2013-02-13 合肥溢鑫电力科技有限公司 Voltage sensor taking zinc oxide resistor as voltage divider, and application thereof
CN104297617A (en) * 2014-10-12 2015-01-21 胡智宏 Measuring transducer for leakage current of lightning arrester
CN105223407A (en) * 2015-09-11 2016-01-06 国家电网公司 500kV Zinc-Oxide Arrester non-dismantle high voltages fuse measures DC leakage method

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CN101975913A (en) * 2010-09-26 2011-02-16 安徽省电力公司六安供电公司 Equipment and method for testing two or more sections of zinc oxide arresters without detaching leads
CN201945652U (en) * 2011-03-23 2011-08-24 辽宁省电力有限公司鞍山超高压分公司 Tester for testing 500kV zinc oxide arrester

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102692581A (en) * 2012-06-19 2012-09-26 国电大渡河检修安装有限公司 Current leakage test method for lightning arrestor
CN102901894A (en) * 2012-09-29 2013-01-30 辽宁省电力有限公司检修分公司 Test method and device for testing 500kV zinc oxide arrester
CN102928646A (en) * 2012-10-24 2013-02-13 合肥溢鑫电力科技有限公司 Voltage sensor taking zinc oxide resistor as voltage divider, and application thereof
CN104297617A (en) * 2014-10-12 2015-01-21 胡智宏 Measuring transducer for leakage current of lightning arrester
CN104297617B (en) * 2014-10-12 2017-07-07 胡智宏 Lightning arrester leakance measurement sensor
CN105223407A (en) * 2015-09-11 2016-01-06 国家电网公司 500kV Zinc-Oxide Arrester non-dismantle high voltages fuse measures DC leakage method

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