CN1652424A - Protecting method for short-circuit between wire coils of parallel reactor of ultrahigh voltage transmission line - Google Patents
Protecting method for short-circuit between wire coils of parallel reactor of ultrahigh voltage transmission line Download PDFInfo
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- CN1652424A CN1652424A CN 200510013091 CN200510013091A CN1652424A CN 1652424 A CN1652424 A CN 1652424A CN 200510013091 CN200510013091 CN 200510013091 CN 200510013091 A CN200510013091 A CN 200510013091A CN 1652424 A CN1652424 A CN 1652424A
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Abstract
Negative sequence voltage and current is calculated from phase voltage and phase current of leading out end at high voltage side of reactor. Based on the calculated value of negative sequence voltage and current, steps of determining short circuit between turns is as follows: when short circuit fault between turns occurs, direction of negative sequence power is determined from phase relation between negative sequence voltage and current; determining whether short circuit fault between turns occurs inside district or outside district. The method increases action sensitivity of protection components, and cancels out characteristics of impedance compensation used in traditional protection in homopolar power direction. The invention protects reactor, determines earth fault, and guarantees not false operation. Theoretical analysis and emulation test prove correctness and validity of the new theory for protecting turns of reactor.
Description
Technical field
The present invention relates to the guard method of power system transmission line shunt reactor, particularly related to a kind of interturn short circuit protection method of the ultra high-tension transmission line shunt reactor based on the negative sequence power orientation principle.
Background technology
The capacitive earth current of remote superhigh pressure, extra-high voltage transmission line is very big, is easy to generate serious overvoltage problem.Use direct-to-ground capacitance, the weakening capacity effect of the inductance energy compensated line of shunt reactor.Simultaneously,, be the success rate of restriction secondary arc current, raising reclosing, often on superhigh pressure and above circuit, all need the shunt reactor of the little reactance of mounting strap neutral point because single-pole reclosing is used widely at supertension line.Therefore shunt reactor obtains to use widely in superhigh pressure, ultra high voltage system as the key equipment of transmission line.
For the superhigh pressure shunt reactor that does not have special switch, its transmission or not operation must be under the electroless state at this circuit to be carried out.Even for the shunt reactor that high-voltage switch gear is arranged, in case it is out of service, power transmission line also can't move.Thus, shunt reactor plays a decisive role to the safe operation of whole system.On-the-spot operation statistics shows that the failure rate of shunt reactor is higher than other equipment of identical electric pressure far away, therefore its protection has been proposed requirements at the higher level.Along with China's electric power system realizes quickening on national network and that build 750kV transmission line process, research large-scale ultrahigh pressure shunt reactor fault and protection thereof are of great importance.
For shunt reactor Inside coil and lead-out wire single-phase earthing or phase fault, differential protecting method can provide sensitive protection.The turn-to-turn short circuit of reactor also is a kind of internal fault form of often seeing.When the short circuit number of turn seldom the time, the three-phase current unbalance that a phase turn-to-turn short circuit causes may be very little, is difficult to detected or finds.And longitudinal differential protection method does not react turn-to-turn fault, and it does not have enough sensitivity when utilizing overcurrent and distance relay to realize the turn-to-turn fault protection, and is subjected to the influence of factors such as magnetizing inrush current big.For improving the sensitivity of inductor turn-to-turn fault, China once developed the reactor interturn short circuit protection of zero sequence power direction principle.But; as a kind of and the most approaching prior art of the present invention, this method is because the zero-sequence component when slight turn-to-turn fault takes place is very little, so zero sequence power direction protection having increased compensation characteristic; but the variation of system operation mode can influence the effect of compensation characteristic, is unfavorable for the use of protecting.
At the deficiency of present shunt reactor protective value, especially the defective of turn-to-turn fault protective value the present invention proposes the inter-turn protection method based on the negative sequence power direction.
Summary of the invention
The objective of the invention is to overcome the defective of prior art; characteristics from turn-to-turn fault preface component; interturn short circuit protection method based on the power transmission line shunt reactor of negative sequence power orientation principle has been proposed; adopt the analysis of negative sequence power directional characteristic, utilize microcomputer to realize analysis and emulation testing fault preface component.
The present invention proposes a kind of interturn short circuit protection method of ultra high-tension transmission line shunt reactor; calculate negative sequence voltage, electric current by phase voltage, the phase current of taking from reactor high-pressure side exit; and carry out the judgement of turn-to-turn short circuit according to this negative sequence voltage, current value, this deterministic process may further comprise the steps:
Carrying out fault preface component calculates;
By judging the phase relation between negative sequence voltage and the negative-sequence current;
Thereby the direction of judging negative sequence power determines whether to have taken place ground short circuit fault in shunt reactor shorted-turn fault or the district.
Compared with prior art; this method since during turn-to-turn fault negative sequence component bigger than the mould value of zero-sequence component; therefore the negative sequence power direction protection has not only improved the sensitivity of turn-to-turn short circuit element action, has also cancelled the impedance-compensated characteristic of traditional zero sequence power direction protection.This method not only provides the protection of shunt reactor turn-to-turn fault; can also realize in the shunt reactor district or the reliable judgement of district's external ground fault; this method can guarantee that shunt reactor can misoperation under non-full-operating state simultaneously, correctly reaches validity through what theory analysis and emulation testing had proved new interturn protection principle.
Below in conjunction with embodiment, and be elaborated, so that the present invention is carried out more deep explanation with reference to accompanying drawing.
Description of drawings
Fig. 1 is the equivalent electric circuit that shunt reactor is connected with extra high voltage system;
Fig. 2 is the fault preface net figure of shunt reactor generation turn-to-turn short circuit;
Fig. 3 is the negative sequence network figure of shunt reactor generation turn-to-turn fault;
Negative sequence network figure when Fig. 4 is the inner generation of shunt reactor earth fault;
Negative sequence network figure when Fig. 5 is the outside generation in shunt reactor district earth fault;
Fig. 6 is the performance chart of negative sequence power direction protection;
Negative phase-sequence loop circuit figure when Fig. 7 is open-phase operation.
Embodiment
The Y type that generally adopts shunt reactor inserts the one or both ends of extra high voltage network, and for suppressing problems such as secondary arc current and resonance overvoltage, shunt reactor often has the little reactance of neutral point.The equivalent electric circuit that shunt reactor is connected with extra high voltage system as shown in Figure 1.Z among the figure
LBe the shunt reactor impedance; Z
NBe the little reactance of neutral point.
During normal the operation, each preface current relationship is
Suppose that turn-to-turn fault takes place shunt reactor A mutually, its impedance variation is Z
FBy symmetrical component method, the fault preface net figure that can calculate turn-to-turn short circuit as shown in Figure 2.
By the map analysis of preface net as can be known, during slight turn-to-turn fault,
Very little, so forward-order current still is approximately
Forward-order current during as seen slight turn-to-turn fault changes very little, so overcurrent protection does not have enough sensitivity to turn-to-turn fault.Pass between negative phase-sequence and the zero-sequence current is:
For extra-high voltage transmission, general Z
0 ∑=(1.5～3) Z
2 ∑sObviously; negative-sequence current mould value during turn-to-turn fault is much larger than zero-sequence current; but the preface electric current when considering slight turn-to-turn fault is less; utilize fault preface current weight can not constitute the performance excellent protection merely, therefore the present invention proposes new interturn protection principle based on the negative sequence power direction to turn-to-turn fault.
Utilize the protective relaying device of microcomputer to be easy to realize the calculating of fault preface component, can realize the turn-to-turn fault guard method that utilizes the power transmission line shunt reactor that the negative sequence power orientation principle realizes proposed by the invention.Its concrete steps comprise: by judging the phase relation between negative sequence voltage and the negative-sequence current, the direction of clear and definite negative sequence power determines whether to take place shorted-turn fault, or earth fault occurs in outside the interior still district, district.Define the negative sequence voltage U of negative sequence power direction protection for this reason
﹠amp; 2Take from the negative sequence voltage on the reactor exit circuit; Negative-sequence current I
﹠amp; 2Take from the high-pressure side of reactor, positive direction is that line flows is to reactor.
Below by specific embodiment, further specify technical scheme of the present invention:
1. utilize the specific implementation method that the negative sequence power directional characteristic carries out in the shunt reactor district, external area error is judged
By symmetrical component method as can be known, when unbalanced fault takes place, can insert one group of asymmetric potential source in network in the fault point, each phase electromotive force of potential source with above-mentioned each asymmetrical voltage equal and opposite in direction, direction are opposite mutually.In negative phase-sequence loop during single-phase turn-to-turn short circuit vertical negative phase-sequence false voltage E must be arranged
﹠amp; 2, establish X
L1, X
L2Be respectively the reactance of both sides, fault point, X
NBe the little reactance of neutral point; X
S2Be the system equivalent negative sequence reactance, then the negative sequence network of turn-to-turn fault as shown in Figure 3.When turn-to-turn fault takes place, take from the on high-tension side negative sequence voltage U of reactor
﹠amp; 2With negative-sequence current I
﹠amp; 2Between the pass be:
The shunt reactor of general superhigh pressure, UHV transmission line is single-phase oil immersion type, so generally only consider single phase ground fault.Be located at reactor inside and earth fault occurs, horizontal negative sequence voltage E2﹠amp appears in the fault point; , its negative sequence network as shown in Figure 4, i.e. negative phase-sequence loop during the reactor internal ground fault.
As seen the negative sequence voltage U during the reactor internal ground fault
﹠amp; 2With negative-sequence current I
﹠amp; 2Between the pass be:
When system side generation earth fault, the negative sequence network when promptly earth fault occurs in outside the shunt reactor district as shown in Figure 5, i.e. negative phase-sequence loop during the external ground fault.
Negative sequence voltage U during reactor external ground fault
﹠amp; 2With negative-sequence current I
﹠amp; 2Between the pass be:
By above analysis as can be known, fault occurs in the district or the district is outer can be judged by position, negative phase-sequence source in system's negative sequence network, thus the sensitivity of protection action when having improved turn-to-turn fault greatly.
Therefore the operating criterion of the negative sequence power direction protection of the present invention's proposition is as follows:
in the formula
LmSystem negative sequence impedance angle is depended at maximum sensitive angle.For guaranteeing negative sequence power direction protection reflected reactance device turn-to-turn fault and internal ground fault, with the negative sequence impedance net resistance consideration, then
Lm=-90 °.Therefore, the operating characteristics of negative sequence power direction protection as shown in Figure 6.
2. the action characteristic analysis of negative sequence power direction protection during non full phases operation of line
Be the stable operation of assurance system and the reliability of power supply, single-pole reclosing is widely used on supertension line.After tripping because of breaking down on the arbitrary phase place of supertension line, circuit enters non-full-operating state.Because three-phase voltage is asymmetric, therefore can produce negative sequence voltage, negative-sequence current, the negative phase-sequence loop of system's this moment when open-phase operation is as shown in Figure 7.
This shows that under the open-phase operation situation, the negative sequence voltage of reactor exit is taken from bus or taken from circuit essential distinction.Work as U
﹠amp; 2Pass when taking from bus bar side and line side between negative sequence voltage and the negative-sequence current is:
By (6) formula as seen, take from bus bar side (negative sequence voltage U when negative sequence voltage
﹠amp; 2M), malfunction must take place in the negative sequence power direction protection; Take from line side (negative sequence voltage U and work as negative sequence voltage
﹠amp; 2L), negative sequence voltage U
﹠amp; 2Be ahead of negative-sequence current I
﹠amp; 2So the negative sequence power direction protection can malfunction.
For the various situations of full operation mutually or fault, the result of determination that negative sequence voltage is taken from line side or bus bar side is consistent.Therefore, the negative sequence voltage of negative sequence power direction protection should be taken from the line side of shunt reactor exit, and negative-sequence current is taken from the reactor high-pressure side, and the definition positive direction is to reactor by line flows.By last analysis as can be known, the negative sequence power direction protection not only can effectively be judged the inside and outside earth fault in district, avoids simultaneously malfunction takes place under the non-full-operating state, also provides sensitive protective feature for inductor turn-to-turn fault.
3. in microcomputer, utilize the negative sequence power directional characteristic to carry out the specific implementation method of reactor fault judgement
The microcomputer relaying protection is easy to realize the calculating to fault preface component.Can calculate negative sequence voltage, electric current by the phase voltage of taking from reactor high-pressure side exit, phase current:
By Microcomputer Protection realize negative sequence power direction protection characteristic that (5) formula expresses as shown in the formula:
When (8) when formula satisfies, then shorted-turn fault has taken place or earth fault in the district has been arranged in explanation.
As seen, negative sequence power direction protection principle is clear, is easy to realize, and turn-to-turn fault is had very high sensitivity, therefore can be used as the main protection of shunt reactor turn-to-turn fault.
Define the negative sequence voltage U of negative sequence power direction protection for this reason
﹠amp; 2Take from the negative sequence voltage on the reactor exit circuit; Negative-sequence current I
﹠amp; 2Take from the high-pressure side of reactor, positive direction is that line flows is to reactor.
Claims (5)
1. the interturn short circuit protection method of a ultra high-tension transmission line shunt reactor; calculate negative sequence voltage, electric current by phase voltage, the phase current of taking from reactor high-pressure side exit; and carry out the judgement of turn-to-turn short circuit according to this negative sequence voltage, current value, this deterministic process may further comprise the steps:
Carrying out fault preface component calculates;
Judge the phase relation between negative sequence voltage and the negative-sequence current;
Direction according to the negative sequence power that calculates judges whether to have taken place turn-to-turn fault or other types fault.
2. the interturn short circuit protection method of ultra high-tension transmission line shunt reactor as claimed in claim 1 is characterized in that the operating criterion of described negative sequence power direction protection is
When negative sequence power telegoniometer formula
Satisfy operating criterion, judge that then the shorted-turn fault that is taken place is a troubles inside the sample space; When negative sequence power telegoniometer formula
Do not satisfy operating criterion, judge that then the shorted-turn fault that is taken place is an external area error.
3. the sensitive angle in the negative sequence power direction protection operating criterion as claimed in claim 1
LmCan realize selecting flexibly by fixed value adjusting according to the real system situation.
4. the interturn short circuit protection method of ultra high-tension transmission line shunt reactor as claimed in claim 1 is characterized in that, when transmission line enters non-full-operating state, and its negative sequence voltage U
2 ﹠amp;Take from the line side, at this moment negative sequence voltage U
2 ﹠amp;With negative-sequence current I
2 ﹠amp;Between the pass be
5. the interturn short circuit protection method of ultra high-tension transmission line shunt reactor as claimed in claim 1 is characterized in that, described fault preface component is realized by the microcomputer relaying protection.
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| CN101651328B (en) * | 2009-08-20 | 2011-10-05 | 深圳南瑞科技有限公司 | Method and device for shunt reactor turn-to-turn protection |
| CN101562331B (en) * | 2009-05-21 | 2012-04-18 | 烟台东方电子信息产业股份有限公司 | Negative sequence reactance direction judging method |
| CN101630832B (en) * | 2008-07-15 | 2012-07-04 | 许继集团有限公司 | Method for judging single-phase earth fault of controllable high-voltage shunt reactor |
| CN101432941B (en) * | 2006-10-18 | 2014-06-04 | Abb技术有限公司 | Load compensation in distance protection of three-phase electric power line |
| CN104330705A (en) * | 2014-11-14 | 2015-02-04 | 国家电网公司 | Line interphase fault single-ended distance measurement method based on interphase fault location factor |
| CN105006802A (en) * | 2015-07-15 | 2015-10-28 | 南京国电南自电网自动化有限公司 | Reactor protecting method based on current amplitude comparison sequence component |
| CN105203903A (en) * | 2015-09-14 | 2015-12-30 | 国网福建省电力有限公司 | Electric transmission line phase-to-phase fault direction recognizing method based on dynamic data window |
| CN106505520A (en) * | 2016-12-01 | 2017-03-15 | 特变电工南京智能电气有限公司 | One kind is taken out can reactor inter-turn protection method and device |
| CN106786368A (en) * | 2016-12-26 | 2017-05-31 | 云南电网有限责任公司电力科学研究院 | The guard method of the dry type hollow shunt reactor based on voltage-phase variable quantity |
| CN109738739A (en) * | 2018-12-20 | 2019-05-10 | 国网北京市电力公司 | Fault detection method and device |
| CN113300341A (en) * | 2021-06-11 | 2021-08-24 | 国网山东省电力公司莱芜供电公司 | Distance protection method based on static synchronous compensator |
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| CN117148214A (en) * | 2023-09-07 | 2023-12-01 | 哈尔滨理工大学 | Online monitoring method for turn-to-turn short circuit fault of dry hollow parallel reactor group of neutral point ungrounded system |
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| RU2224342C2 (en) * | 2000-09-19 | 2004-02-20 | ОАО "Институт "Энергосетьпроект" | Short-circuit protective device for parallel ac power transmission lines |
| CN100369342C (en) * | 2003-11-27 | 2008-02-13 | 南京南瑞继保电气有限公司 | High-voltage shunt reactor protecting method between turns |
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- 2005-01-13 CN CNB2005100130913A patent/CN100442623C/en not_active Expired - Fee Related
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| CN101432941B (en) * | 2006-10-18 | 2014-06-04 | Abb技术有限公司 | Load compensation in distance protection of three-phase electric power line |
| CN101630832B (en) * | 2008-07-15 | 2012-07-04 | 许继集团有限公司 | Method for judging single-phase earth fault of controllable high-voltage shunt reactor |
| CN101562331B (en) * | 2009-05-21 | 2012-04-18 | 烟台东方电子信息产业股份有限公司 | Negative sequence reactance direction judging method |
| CN101651328B (en) * | 2009-08-20 | 2011-10-05 | 深圳南瑞科技有限公司 | Method and device for shunt reactor turn-to-turn protection |
| CN104330705B (en) * | 2014-11-14 | 2017-07-28 | 国家电网公司 | Circuit inter-phase fault single-end ranging based on phase-to phase fault location factor |
| CN104330705A (en) * | 2014-11-14 | 2015-02-04 | 国家电网公司 | Line interphase fault single-ended distance measurement method based on interphase fault location factor |
| CN105006802B (en) * | 2015-07-15 | 2017-10-31 | 南京国电南自电网自动化有限公司 | Reactor protection method based on electric current than width formula order components |
| CN105006802A (en) * | 2015-07-15 | 2015-10-28 | 南京国电南自电网自动化有限公司 | Reactor protecting method based on current amplitude comparison sequence component |
| CN105203903A (en) * | 2015-09-14 | 2015-12-30 | 国网福建省电力有限公司 | Electric transmission line phase-to-phase fault direction recognizing method based on dynamic data window |
| CN105203903B (en) * | 2015-09-14 | 2018-11-06 | 国网福建省电力有限公司 | Based on dynamic data window electric transmission line phase fault discriminating direction method |
| CN106505520B (en) * | 2016-12-01 | 2019-05-24 | 特变电工南京智能电气有限公司 | A kind of pumping energy reactor inter-turn protection method and device |
| CN106505520A (en) * | 2016-12-01 | 2017-03-15 | 特变电工南京智能电气有限公司 | One kind is taken out can reactor inter-turn protection method and device |
| CN106786368A (en) * | 2016-12-26 | 2017-05-31 | 云南电网有限责任公司电力科学研究院 | The guard method of the dry type hollow shunt reactor based on voltage-phase variable quantity |
| CN106786368B (en) * | 2016-12-26 | 2018-12-18 | 云南电网有限责任公司电力科学研究院 | The guard method of dry type hollow shunt reactor based on voltage-phase variable quantity |
| CN109738739A (en) * | 2018-12-20 | 2019-05-10 | 国网北京市电力公司 | Fault detection method and device |
| CN113300341A (en) * | 2021-06-11 | 2021-08-24 | 国网山东省电力公司莱芜供电公司 | Distance protection method based on static synchronous compensator |
| CN114050552A (en) * | 2021-11-17 | 2022-02-15 | 许继集团有限公司 | Shunt reactor turn-to-turn protection method and device |
| CN114050552B (en) * | 2021-11-17 | 2023-09-15 | 许继集团有限公司 | Inter-turn protection method and device for shunt reactor |
| CN117148214A (en) * | 2023-09-07 | 2023-12-01 | 哈尔滨理工大学 | Online monitoring method for turn-to-turn short circuit fault of dry hollow parallel reactor group of neutral point ungrounded system |
| CN117148214B (en) * | 2023-09-07 | 2024-03-19 | 哈尔滨理工大学 | Online monitoring method for turn-to-turn short circuit fault of dry hollow parallel reactor group of neutral point ungrounded system |
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Assignee: Deweite Electric Power System Automatic Co., Ltd., Beijing Assignor: Tianjin University Contract fulfillment period: 2008.12.10 to 2013.12.10 contract change Contract record no.: 2009120000004 Denomination of invention: Protecting method for short-circuit between wire coils of parallel reactor of ultrahigh voltage transmission line Granted publication date: 20081210 License type: Exclusive license Record date: 2009.3.17 |
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