CN102565618A - Method for detecting zero-sequence voltage circuit of transformer substation - Google Patents
Method for detecting zero-sequence voltage circuit of transformer substation Download PDFInfo
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- CN102565618A CN102565618A CN2012100213297A CN201210021329A CN102565618A CN 102565618 A CN102565618 A CN 102565618A CN 2012100213297 A CN2012100213297 A CN 2012100213297A CN 201210021329 A CN201210021329 A CN 201210021329A CN 102565618 A CN102565618 A CN 102565618A
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Abstract
The invention discloses a method for detecting a zero-sequence voltage circuit of a transformer substation. A voltage transformer can be added with a 220V single-phase test voltage for one time before the transformer substation is in charged production, by the adoption of a high-accuracy universal meter, a zero-sequence voltage amplitude value between a terminal of a zero-sequence voltage outlet line L and the terminal of a grounding line N of a terminal box is detected to be ULN1, a voltage amplitude value between the terminal of the zero-sequence voltage outlet line L and the added test voltage A is detected to be ULA, and the voltage amplitude value between the test voltage A and the grounding line N is detected to be UAN; then, the voltage transformer can be added with a 380V three-phase symmetrical positive phase sequence line voltage for one time, and the voltage amplitude value between the zero-sequence voltage outlet line L and the grounding line N is detected to be ULN2; at last, the measured data can be analyzed, the polarity of outlet lines L of zero-sequence voltage secondary windings of a grounding terminal is the same as that of a high-voltage side of a primary winding if UAN=ULN1+ULA, a zero-sequence secondary winding a, a zero-sequence secondary winding b and a zero-sequence secondary winding c can be judged to be in like polarity connection in series if the voltage amplitude value ULN2 is 0, and thus whether the zero-sequence voltage connection of the terminal box is correct or not can be judged. According to the method disclosed by the invention, the connection of a zero-sequence voltage secondary circuit of the transformer substation can be detected, a zero-sequence voltage circuit which is in leaked connection and misconnection can be found, the inspection for the zero-sequence voltage secondary circuit can be more comprehensive to implement, convenience is provided for the operation, and the effectiveness and the reliability of the inspection are high.
Description
Technical field
The invention belongs to electrical technology field, before operation,, guarantee the method for inspection of residual voltage circuit connection correctness through making an experiment especially for transformer station.
Background technology
Now, electric power has become the indispensable necessity for life of people, and transformer station is the important step that electric power is carried, and whether its residual voltage loop correctness, will have influence on the safety and stability of electrical network, and what influence electric power normally provides the normal life with people.The mistake in residual voltage loop can cause EMR electromagnetic resonance harm, influences the adverse consequencess such as correct operation of electric grid relay protection.
Singlephase earth fault is a 110kV transmission and distribution network common faults type the most; Cause behind the single-phase earthing that the system zero sequence voltage raises, in service once repeatedly the appearance causes that owing to the circuit single-phase earthing adjacent transformers neutral point gap breakdown causes relay protection to lose optionally case.In actual moving process, progressively strengthened research to the system zero sequence loop.
The residual voltage loop is an important component part in the grid power system, mainly comprises: zero sequence Secondary Winding and binding post, the cable connection between terminal box, indoor secondary screen cabinet and connection device and screen cabinet is formed on the spot.
Before the charged operation of transformer station; Prior art be adopt voltage transformer (VT) on the spot terminal box rise the method for inspection of secondary voltage, as shown in Figure 2, after the transformer station loop connects; Off voltage mutual inductor side loop; With the equipment of boosting, to screen cabinet side secondary circuit, add secondary voltage at terminal box on the spot.The protection screen cabinet terminal in the pulpit is measured screen cabinet zero sequence terminal voltage with multimeter.This method of inspection can only be checked the residual voltage loop of shielding cabinet to the pulpit from terminal box on the spot.Can not check to the terminal box loop from zero sequence Secondary Winding binding post to obtain that the wiring between the zero sequence Secondary Winding can not be checked through, have obviously inspection dead angle.If short circuit is arranged, produce residual voltage and may cause equipment burnout at secondary zero sequence winding connection post.
Usually, voltage transformer (VT) has 2 groups of voltage outputs, and one group is 57. 7V (theoretical values), is used for forming star-star connection; One group is 100 V (theoretical values), is used for forming the zero sequence circuit connection of open-delta.Though wiring error does not take place in SC unavoidably in the installation yet.When wiring error appears in the open-delta loop, generally can produce superpotential, will jeopardize secondary device safety.
After the zero sequence winding put into operation, normal operation did not produce residual voltage, can't carry out deep affirmation to residual voltage wiring polarity etc., when the network system system breaks down, incorrect residual voltage was provided, and can cause electric grid relay protection malfunction accident.
Therefore, how before the charged operation of transformer station, should find and solve open-delta zero sequence wiring error problem, the safe and stable operation of electrical network is had important meaning through check.
Summary of the invention
Under such technical background; For solving the problem that exists; The present invention provides a kind of and can test to the connection of transformer station's residual voltage secondary circuit; Find to leak, the wrong residual voltage circuit connection that connects, more comprehensive to the inspection of residual voltage secondary circuit, and simple and convenient, workload is few, the validity and the high method of inspection of reliability of inspection.
Technical scheme of the present invention is following.
Transformer station's residual voltage in-circuit testing method, before the charged operation of transformer station, operation according to the following steps:
1. voltage transformer (VT) once adds single-phase 220V trial voltage, uses the high precision multimeter, and the residual voltage amplitude of detection terminal case residual voltage outlet L terminal and ground wire N terminal is U
LN1, zero sequence outlet L terminal is U with the voltage magnitude of the electrical verification of the adding an examination of pressure A of institute
LA, the voltage magnitude of trial voltage A and ground wire N is U
ANThe residual voltage air switch that closes, to detect the voltage magnitude of L and N be U to screen cabinet terminal in the pulpit
LN1';
2. once add three symmetrical positive phase sequence 380V line voltages, the voltage magnitude of detection terminal case residual voltage outlet L and ground wire N is U
LN2The residual voltage air switch that closes, to detect the voltage of L and N be U to screen cabinet terminal in the pulpit
LN2';
3. to above-mentioned steps 1. with step 2. data measured analyze, judge the correct of wiring; To the determination methods of data, if satisfy U
AN=U
LN1+ U
LA, then terminal residual voltage Secondary Winding extension line L and a winding high-pressure side are same polarities on the spot; If U
LN2Magnitude of voltage is zero, can judge that then the same polarity that is connected to of zero sequence Secondary Winding a, b, c is connected in series; Can draw the conclusion of terminal box residual voltage wiring correctness through two judgements and designing requirement; If the residual voltage that records at terminal box on the spot is identical with the residual voltage that cabinet is shielded in the pulpit, judge that then open the wiring to the relay-set terminal again from terminal on the spot to the zero sequence sky correct; Do not satisfy if detect data, or no-voltage is then judged the loop existing problems.
Through above step, can guarantee the correct of transformer station whole residual voltages loop.
The present invention compared with prior art has the following advantages:
(1) validity of this method of inspection, reliability are higher.If there are false wiring problems such as the residual voltage secondary is short-circuited, can not cause device damage yet, can in time find the mistakes and omissions wiring after, have ample time and search and handle problems.
(2) more comprehensive to the inspection of residual voltage secondary circuit.Zero sequence Secondary Winding, winding connection post, secondary connection post are to the wiring of terminal box on the spot, and terminal box all can both be checked to obtain to secondary screen cabinet terminal connections on the spot.
(3) this method device therefor material is simple and convenient, and workload is few.
Below in conjunction with Figure of description and embodiment the present invention is further specified.
Description of drawings
Fig. 1 is for adding single phase poaer supply test synoptic diagram;
Fig. 2 is for adding three-phase supply test synoptic diagram;
Fig. 3 is same polarity serial connection voltage vector diagram;
Fig. 4 connects the inverse voltage vector plot for A phase polarity.
Embodiment
Transformer station's residual voltage in-circuit testing method, the present invention is characterised in that, before the charged operation of transformer station, operates as follows:
The first step, voltage transformer (VT) once add single-phase 220V trial voltage, use the high precision multimeter, and the residual voltage amplitude of detection terminal case residual voltage outlet L terminal and ground wire N terminal is U
LN1, zero sequence outlet L terminal is U with the voltage magnitude of the electrical verification of the adding an examination of pressure A of institute
LA, the voltage magnitude of trial voltage A and ground wire N is U
ANThe residual voltage air switch that closes, to detect the voltage magnitude of L and N be U to screen cabinet terminal in the pulpit
LN1';
Second step once added three symmetrical positive phase sequence 380V line voltages, and the voltage magnitude of detection terminal case residual voltage outlet L and ground wire N is U
LN2The residual voltage air switch that closes, to detect the voltage of L and N be U to screen cabinet terminal in the pulpit
LN2';
The 3rd step, the first step and the second step data measured are analyzed, judge the correct of wiring; To the determination methods of data, if satisfy U
AN=U
LN1+ U
LA, then terminal residual voltage Secondary Winding extension line L and a winding high-pressure side are same polarities on the spot; If U
LN2Magnitude of voltage is zero, can judge that then the same polarity that is connected to of zero sequence Secondary Winding a, b, c is connected in series; Can draw the conclusion of terminal box residual voltage wiring correctness through two judgements and designing requirement;
If the residual voltage that records at terminal box on the spot is identical with the residual voltage that cabinet is shielded in the pulpit, judge that then open the wiring to the relay-set terminal again from terminal on the spot to the zero sequence sky correct; Data do not satisfy or no-voltage is then judged the loop existing problems if detect.
Existing is example with certain 110kV transformer station, below sketches implementation process.The briefing of transformer station is: it is 110kV/35kV/10kV that main-transformer has three electric pressures, and 110kV side residual voltage winding no-load voltage ratio is k=110kV/173V.
1, theoretical analysis
See Fig. 1, residual voltage is accomplished in the ground terminal case by the wiring of voltage transformer (VT) open-delta Secondary Winding, and what guide to central authorities control (protection) chamber through cable connection is residual voltage loop L, N line, wherein N in the pulpit ground connection.
See Fig. 2, when transformer station added three symmetrical 380V line voltages (220V phase voltage) a 110kV side, the voltage magnitude of voltage transformer (VT) zero sequence secondary coil a was U
a, the voltage magnitude of secondary coil b is U
b, the voltage magnitude of secondary coil c is U
c, U
a=U
b=U
c220V/k=0.346V voltage, three characteristics of the middle term voltage are complete symmetrical balances, residual voltage is that three-phase zero sequence secondary coil is connected in series by same polarity, sees Fig. 3, opening residual voltage U
LN=U
a+ U
b+ U
c=0.See Fig. 4, when the outlet of A phase coil connects instead, then the opening residual voltage should be U
LN=-U
a+ U
b+ U
c, residual voltage U
LNBe 2 * U
a=0.692V.
When mutually earth fault taking place, imbalance of three-phase voltage just has residual voltage U when a certain
LNOutput, the operations staff fixes a breakdown with prompting, or offers relay protection and export tripping operation and judge.
If at a 110kV side A phase institute making alive is single-phase 220V, then U
b=U
c=0, residual voltage should be U
LN=U
a=220V/k=0.346V.
Step 1 is seen Fig. 1, and through adding single-phase trial voltage in the 110kV side, the air that closes is opened
Close, relevant voltage is detected.Step 2 is seen Fig. 2, the air switch that closes, through once, boosting adds three-phase positive phase sequence symmetry 380V (220V phase voltage) trial voltage,, make A, B, C mutually a winding be with three-phase positive phase sequence symmetry 380V voltage simultaneously, the residual voltage loop is detected.Step 3 is analyzed detecting data, judges whether voltage circuit is correct.
The required major equipment material of testing has: one of three-phase voltage increasing equipment, one in the high accuracy number multimeter of measuring voltage, some on experiment power supply line, one of the three-phase air switch of control power supply.
2. test concrete steps
1. winding of A phase (or other arbitrary phases) is charged
See Fig. 1, dotted portion is a test connection, and heavy line is the transforming plant primary wiring, and fine line is a secondary connection, and experiment power supply is adjustable single-phase AC 220V voltage.
The test air switch that closes is regulated boosted voltage to about 220V, and a winding is charged mutually to make A, measures measurement U with the voltage table of high precision, pin-point accuracy
AAnd magnitude of voltage is U between N
AN=220.1V measures U
AAnd magnitude of voltage is U between L
AL=219.75V measures U at terminal
LAnd the opening magnitude of voltage is U between N
LN1=0.348V.
The residual voltage sky that closes is opened, and the relay-set terminal is measured U in the pulpit
LAnd the opening magnitude of voltage is U between N
LN1 '=0.347V.
2. a winding three-phase is charged.
See Fig. 2, the test air switch that closes once adds three positive phase sequence 380V line voltages (phase voltage 220V), and one time winding is charged.Carry out the secondary circuit voltage detecting at terminal box.Measure U at terminal
LAnd the residual voltage value is U between N
LN2=0.01V.
The residual voltage sky that closes is opened, and pieces together the cabinet terminal in relay protection and measures U
LAnd the opening magnitude of voltage is U between N
LN2 '=0.01V.
3. judge detecting data
To the judgement of data, if U
AN=U
LA+ U
LN1, then terminal residual voltage loop outlet L and a winding high-pressure side are same polarities on the spot; If U
AN=U
LA-U
LN1, then terminal residual voltage loop outlet L and a winding high-pressure side are reversed polarity on the spot.Satisfy U according to measured data
AN=220.1 V, U
LA+ U
LN1=219.75V+0.348V=220.108 is so satisfy U
AN=U
LA+ U
LN1
Condition can judge that terminal residual voltage loop outlet L and a winding A high-pressure side are same polarities on the spot.If U
LN2Magnitude of voltage is zero, and that then judges zero sequence Secondary Winding a, b, c is connected to the wiring of same polarity polyphone; If non-vanishing, wiring error is arranged then.Draw the conclusion of terminal box wiring correctness then according to designing requirement.
U
LN1=U
LN1 'Consistent with calculated value, U
LN2=U
LN2 'Consistent with calculated value, judge that then open the wiring to the relay-set terminal again from terminal on the spot to the zero sequence sky correct.Then broken string is arranged the loop if detect complete no-voltage.
Through above step, can guarantee the correct of residual voltage loop.
Claims (1)
1. transformer station's residual voltage in-circuit testing method is characterized in that, before the charged operation of transformer station, and operation according to the following steps:
1. voltage transformer (VT) once adds single-phase 220V trial voltage, uses the high precision multimeter, and the residual voltage amplitude of detection terminal case residual voltage outlet L terminal and ground wire N terminal is U
LN1, zero sequence outlet L terminal is U with the voltage magnitude of the electrical verification of the adding an examination of pressure A of institute
LA, the voltage magnitude of trial voltage A and ground wire N is U
ANThe residual voltage air switch that closes, to detect the voltage magnitude of L and N be U to screen cabinet terminal in the pulpit
LN1';
2. once add three symmetrical positive phase sequence 380V line voltages, the voltage magnitude of detection terminal case residual voltage outlet L and ground wire N is U
LN2The residual voltage air switch that closes, to detect the voltage of L and N be U to screen cabinet terminal in the pulpit
LN2';
3. to above-mentioned steps 1. with step 2. data measured analyze, judge the correct of wiring; To the determination methods of data, if satisfy U
AN=U
LN1+ U
LA, then terminal residual voltage Secondary Winding extension line L and a winding high-pressure side are same polarities on the spot; If U
LN2Magnitude of voltage is zero, can judge that then the same polarity that is connected to of zero sequence Secondary Winding a, b, c is connected in series; Can draw the conclusion of terminal box residual voltage wiring correctness through two judgements and designing requirement; If the residual voltage that records at terminal box on the spot is identical with the residual voltage that cabinet is shielded in the pulpit, judge that then open the wiring to the relay-set terminal again from terminal on the spot to the zero sequence sky correct; Do not satisfy if detect data, or no-voltage is then judged the loop existing problems.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012100213297A CN102565618A (en) | 2012-01-31 | 2012-01-31 | Method for detecting zero-sequence voltage circuit of transformer substation |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012100213297A CN102565618A (en) | 2012-01-31 | 2012-01-31 | Method for detecting zero-sequence voltage circuit of transformer substation |
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ID=46411532
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| CN2012100213297A Pending CN102565618A (en) | 2012-01-31 | 2012-01-31 | Method for detecting zero-sequence voltage circuit of transformer substation |
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103076529A (en) * | 2012-12-27 | 2013-05-01 | 山东电力集团公司检修公司 | CT (Current Transformer) secondary circuit intelligent-detection method |
| CN103969540A (en) * | 2013-01-30 | 2014-08-06 | 江苏省电力公司常州供电公司 | Method for testing wiring of secondary circuits of four-star voltage transformers |
| CN104833836A (en) * | 2015-04-23 | 2015-08-12 | 本钢板材股份有限公司 | Zero sequence voltage detection method for voltage transformer |
| CN105445609A (en) * | 2015-12-01 | 2016-03-30 | 国网河南宜阳县供电公司 | Testing device and method for high voltage supply system loop |
| CN105891613A (en) * | 2014-11-19 | 2016-08-24 | 国家电网公司 | Method for measuring phase sequence of power transmission line by using power frequency parameter tester |
| CN106814278A (en) * | 2017-02-21 | 2017-06-09 | 云南电网有限责任公司 | Plant stand take out can it is high anti-once and secondary current loop Site Detection and determination methods |
| CN110133565A (en) * | 2019-06-20 | 2019-08-16 | 安徽马钢设备检修有限公司 | A kind of voltage transformer method of calibration |
| CN110850352A (en) * | 2019-12-01 | 2020-02-28 | 国网辽宁省电力有限公司锦州供电公司 | Secondary circuit wiring checking method of 10kV voltage transformer |
| CN113156276A (en) * | 2021-02-22 | 2021-07-23 | 云南建投第二安装工程公司 | Method for checking and debugging secondary voltage loop in AC withstand voltage test of switchgear bus |
| CN114325484A (en) * | 2021-12-23 | 2022-04-12 | 广州发展电力科技有限公司 | Method for checking wiring of secondary circuit of voltage transformer of generator |
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Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103076529A (en) * | 2012-12-27 | 2013-05-01 | 山东电力集团公司检修公司 | CT (Current Transformer) secondary circuit intelligent-detection method |
| CN103076529B (en) * | 2012-12-27 | 2015-10-28 | 山东电力集团公司检修公司 | CT secondary circuit intelligent detecting method |
| CN103969540B (en) * | 2013-01-30 | 2016-06-22 | 江苏省电力公司常州供电公司 | The method of testing of four wye voltage transformer secondary circuit wiring |
| CN103969540A (en) * | 2013-01-30 | 2014-08-06 | 江苏省电力公司常州供电公司 | Method for testing wiring of secondary circuits of four-star voltage transformers |
| CN105891613A (en) * | 2014-11-19 | 2016-08-24 | 国家电网公司 | Method for measuring phase sequence of power transmission line by using power frequency parameter tester |
| CN104833836A (en) * | 2015-04-23 | 2015-08-12 | 本钢板材股份有限公司 | Zero sequence voltage detection method for voltage transformer |
| CN105445609A (en) * | 2015-12-01 | 2016-03-30 | 国网河南宜阳县供电公司 | Testing device and method for high voltage supply system loop |
| CN106814278A (en) * | 2017-02-21 | 2017-06-09 | 云南电网有限责任公司 | Plant stand take out can it is high anti-once and secondary current loop Site Detection and determination methods |
| CN110133565A (en) * | 2019-06-20 | 2019-08-16 | 安徽马钢设备检修有限公司 | A kind of voltage transformer method of calibration |
| CN110850352A (en) * | 2019-12-01 | 2020-02-28 | 国网辽宁省电力有限公司锦州供电公司 | Secondary circuit wiring checking method of 10kV voltage transformer |
| CN113156276A (en) * | 2021-02-22 | 2021-07-23 | 云南建投第二安装工程公司 | Method for checking and debugging secondary voltage loop in AC withstand voltage test of switchgear bus |
| CN113156276B (en) * | 2021-02-22 | 2024-03-29 | 云南建投第二安装工程公司 | Method for checking and debugging secondary voltage loop of bus alternating-current withstand voltage test of switching equipment |
| CN114325484A (en) * | 2021-12-23 | 2022-04-12 | 广州发展电力科技有限公司 | Method for checking wiring of secondary circuit of voltage transformer of generator |
| CN114325484B (en) * | 2021-12-23 | 2024-03-22 | 广州发展电力科技有限公司 | Wiring inspection method for secondary circuit of generator voltage transformer |
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Application publication date: 20120711 |