CN1725590A - Step down transformer and relay protection method of middle low voltage side bus - Google Patents
Step down transformer and relay protection method of middle low voltage side bus Download PDFInfo
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- CN1725590A CN1725590A CN 200510043957 CN200510043957A CN1725590A CN 1725590 A CN1725590 A CN 1725590A CN 200510043957 CN200510043957 CN 200510043957 CN 200510043957 A CN200510043957 A CN 200510043957A CN 1725590 A CN1725590 A CN 1725590A
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Abstract
This invention relates to a step-down transformer and its relay protection method for its lower-middle voltage side bus bar characterizing in quickly determining positions of fault spots by logically comparing the operation states of measured elements at each side of a transformer and at each exit position of the lower-middle bus bar and removes the fault device in a small action time limit to realize the quick backup protection of transformer in a step-down substation and a master protection to the lower-middle voltage side bus bar.
Description
Affiliated technical field
The invention belongs to field of relay protection in power, relate generally to a kind of based on the step-down transformer of vertical connection comparison principle and the relay protecting method of mesolow side bus thereof.
Background technology
In electric power system, account for the transformer station of sum more than 2/3rds and be step-down substation, the bus of step-down transformer and mesolow side thereof is the visual plant in the step-down substation.At present; transformer is all with differential protection and the protection main protection as internal fault; and the general overcurrent protection of dividing side independently to install that adopts comprises that general time-delay overcurrent protection, low-voltage lockout overcurrent protection, composite voltage locking overcurrent protection etc. protect in support.The bus of step-down transformer mesolow side is not generally installed special protective relaying device, and the fault of bus mainly relies on the backup protection of transformer mesolow side to move and excises, and general operate time is all long.The dual role of middle voltage bus bar main protection and outlet backup protection thereof is being born in the backup protection of transformer mesolow side; and the transformer high-voltage rear flank is equipped with protection except that the backup protection as power transformer interior fault, also will be as the backup protection of mesolow side bus and outlet thereof.For guaranteeing the selectivity of protection action, require three rear flank to be equipped with protection and on sensitivity and operation time limit, must cooperatively interact, generally require the sensitivity of high-pressure side backup protection should be lower than the mesolow side, and operate time, the aspect required t
The high-pressure side＞t
Medium voltage side＞t
Low-pressure sideBecause will match with the II section or the III section of low-voltage side outlet the operate time of low-pressure side usually, its value generally will be more than 1 second, so medium voltage side and on high-tension side operate time will be longer, under the situation of some, on high-tension side time-delay may reach more than 3 seconds.As seen, according to present protection configuration mode, during the fault of transformer mesolow side bus, or when power transformer interior fault but its main protection tripping, need through the long time could be with failure removal.In addition, in some cases, the protection range of high-pressure side backup protection may not reach low-pressure side bus, makes low-pressure side bus simple time-delay overcurrent protection only be arranged as unique protection, in case should protect tripping, fault can't be excised automatically, will cause that accident enlarges.
Summary of the invention
The objective of the invention is to overcome the deficiencies in the prior art, provide a kind of simple and reliable, be swift in motion, sensitivity is higher, based on the step-down transformer of vertical connection comparison principle and the relay protecting method of mesolow side bus thereof.
The present invention realizes in the following manner:
Proposed the relay protecting method of a kind of step-down transformer and mesolow side bus thereof, it is characterized in that:
(1) measuring component that can reflect fault direction in the outlet and the installing of bar coupler place of each side of transformer, middle voltage bus bar: the mesolow side at transformer does not all have under the situation of power supply, with by escaping overcurrent element that maximum load current adjusts as measuring component; There are power supply or mesolow side all to have under the situation of power supply at medium voltage side or low-pressure side, use direction component as measuring component in the outlet of side that power supply is arranged and connection power supply;
(2) positive direction of regulation transformer high-voltage side direction element is for to point to protected transformer by high voltage bus, the positive direction of mesolow side direction element is pointed to middle voltage bus bar by protected transformer, the positive direction of outlet direction component is pointed to circuit by bus, and the bus prescription points to another bus to the positive direction of element by protected bus;
(3) when high-pressure side measuring component action and the measuring component of mesolow side when all being failure to actuate is judged as power transformer interior fault;
When (4) measuring component central, the low-pressure side either side moves, just be judged as this side fault: if the measuring component at each outlet of this side bus and network interconnecting circuit place all is failure to actuate, be judged as this side bus fault, all electric power incoming lines that the quick tripping of protection action links to each other with this bus; When the measuring component at arbitrary outlet or network interconnecting circuit place moves; be judged as this outlet or another busbar fault (being the external area error of protected transformer and bus); starting backup protection logic; under the situation of outlet, female connection protection or circuit breaker tripping, the time-delay tripping is connected all electric power incoming lines on this side bus.
The relay protecting method of above-mentioned step-down transformer and mesolow side bus thereof is characterized in that the action message of measuring component, i.e. the quantity of state of each measuring component, by transformer station's inner high speed communication network (Ethernet, optical fiber etc.) or directly physical connection transmit.
Compared with prior art, the present invention is based on the step-down transformer of vertical connection comparison principle and the relay protecting method of middle voltage bus bar thereof following advantage is arranged: it relatively is installed in the action message of the measuring component of each side by logic, can judge location of fault accurately, for in, low-pressure side bus provides quick main protection, and shortens the operation time limit of power transformer interior fault backup protection greatly; It does not need each rear flank of transformer to protect operation time limit to cooperate fully, and when power transformer interior fault and differential main protection tripping, only need escape magnetizing inrush current just can directly jump three side switches; In, when breaking down on the low-voltage bus bar, need not delay time and wait for and just can apace fault bus be excised; When the outlet beyond the bus or another bus beyond the network interconnecting circuit break down (concerning this protection system, being equivalent to external fault), only need also can play the effect of backup protection according to traditional configuration mode.After promptly adopting scheme proposed by the invention, can accelerate the excision speed of transformer fault and middle voltage bus bar fault, and can not influence the backup protection function of centering low-voltage side outlet.
Description of drawings
Fig. 1 is a principle schematic of the present invention;
Fig. 2 is the schematic diagram of the present invention by transformer station's intercommunication network delivery status amount;
Fig. 3 is the schematic diagram of the present invention by direct physical line delivery status amount;
Fig. 4 is the theory diagram of logical block one among Fig. 3;
Fig. 5 is the theory diagram of logical block two among Fig. 3;
Fig. 6 is the theory diagram of logical block three among Fig. 3.
Among the figure:
111 is the measuring component of transformer high-voltage side, 351 is the measuring component of transformer medium voltage side, 101 is the measuring component of step down side, 353,354 (only show the situation of two outlets for the measuring component of each outlet of medium voltage side bus, during specific implementation, go out number of lines allocating and measuring element by reality), 352 is the measuring component at medium voltage side network interconnecting circuit place, 103,104 (only show the situation of two outlets for the measuring component of each outlet of low-pressure side bus, during specific implementation, go out number of lines allocating and measuring element by reality), 102 is the measuring component at low-pressure side network interconnecting circuit place;
QF1, QF2, QF3 are respectively the circuit breaker of each side of transformer, during QF4, QF5 are respectively, the bus-tie circuit breaker of low-pressure side;
1 is the logic comparing unit, and 2 is transformer station's inner high speed communication network, and 3 is physical connection; 4 is that logical block one, 5 is that logical block two, 6 is a logical block three;
t
1Be the outlet time-delay of bus main protection, t
2Be the operation time limit of low-pressure side backup protection, t
3Be the operation time limit of medium voltage side backup protection, t
4The operation time limit of backup protection during for power transformer interior fault.
Embodiment
Provide a most preferred embodiment of the present invention below in conjunction with accompanying drawing.
All not having the 110kV step-down substation of power supply with the mesolow side shown in the accompanying drawing 1 is example; this example only considers that transformer station has only the situation of a transformer; for the common situation that two or three transformers are arranged, as long as outfit two covers or the same protection system of three covers promptly can realize.Transformer in this example is a three-winding transformer; the situation that no-load voltage ratio is among the 110/35/10kV, low-pressure side bus all only considers to have only two outlets and a network interconnecting circuit; for going out the situation of number of lines more than two; only need go out the quantity that number of lines is equipped with measuring component by actual, this example of formation logical AND of protection is just the same.
At three sides of protected transformer, each outlet and the bus-tie circuit breaker place of middle voltage bus bar; each installs one by escaping overcurrent element that maximum load current adjusts as measuring component, and wherein the measuring component at each outlet and bus place also can be multiplexing with the III section in outlet and the female connection protection.This overcurrent element both can be a microcomputer type, also can be electromagnetic type, and this example considers to use microcomputer type.When electric power system was broken down, each measuring component was all made reflection, the state information that provides action respectively or be failure to actuate according to the position of fault point.The state information of these measuring component actions, form output with digital signal or relay dry contact, when with the output of the form of digital signal, need the output of each measuring component to be pooled to the vertical logic comparing unit (module 1 of accompanying drawing 2) that joins by station communication network (as Ethernet); And when exporting with the form of relay dry contact, then need with physical connection the output of all measuring components to be pooled to vertical connection logic comparing unit (module 1 of accompanying drawing 3).
The logic comparing unit is realized with a programmable logic controller (PLC) (PLC), also can realize with other microcomputer systems (single-chip microcomputer, industrial computer etc.).It logically comprises three unit, i.e. logical block one, logical block two and logical block three are shown in the module among Fig. 34,5,6.The theory diagram of logical block one as shown in Figure 4, it is used for judging the internal fault of transformer; The theory diagram of logical block two as shown in Figure 5, it is used for judging the busbar fault and the external fault of transformer medium voltage side; The theory diagram of logical block three as shown in Figure 6, it is used for judging the busbar fault and the external fault of step down side.
Under the single supply operational mode, the overcurrent element action illustrates that fault occurs in power supply and protects outside the mounting points, otherwise, illustrate that fault occurs between power supply and the protection mounting points or on other branch roads.By comparison, just can judge out of order section fast, and faulty equipment be excised according to predetermined logic to each overcurrent measuring component operate condition.
When measuring component 111 action, and 351 and 101 when all being failure to actuate, and the generation power transformer interior fault be described.If the differential protection of transformer or protection action, then after each side circuit breaker disconnected, 111 returned, and this protection system also will be returned; If differential protection tripping, then t
4The circuit breaker of time-delay back tripping mains side, as shown in Figure 4.t
4Adjust according to the duration of avoiding magnetizing inrush current, for the step-down transformer of middle low capacity, because the magnetizing inrush current decay is very fast, t
4Generally be no more than 0.5～1s.
When measuring component 351 actions, illustrate that medium voltage side has fault.If 352,353,354 when all being failure to actuate, illustrate that fault point one fixes on the medium voltage side bus, protect this moment with than short time delay t
1Tripping QF2, QF4; When any moves in 352,353,354, illustrate that the fault point is not on protected bus, but in bus-tie circuit breaker opposite side or outlet, if the protection of bus or the protection correct operation of outlet, then behind failure removal 351 and another measuring component (any in 352,353,354) that has moved return; If the protection of bus or the protection tripping of outlet, then this protection is with the time limit t that matches with mother's connection or outlet backup protection time-delay
3Tripping QF2, QF4, as shown in Figure 5.t
1Be the delay time that is provided with for the reliability that improves action, its value is no more than 50ms, t
3Value consistent with the backup protection of adopting at present, on the basis of outlet protection action delay, increase a differential Δ t of time.Logic shown in Figure 5 can either be finished the quick main protection function of medium voltage side bus, also has both the defencive function that is equipped with of outlet.
The situation of low-pressure side fault as shown in Figure 6, the situation of it and medium voltage side fault shown in Figure 5 is in full accord.
For in, low-pressure side has the situation of power supply, at transformer the branch road that power supply is arranged in the side of power supply and the outlet is arranged, employing based on the direction component of fault component as its measuring component, the reference direction of all directions element has following provisions: the direction component of transformer high-voltage side is for pointing to transformer from high-voltage side bus, in, the direction component of low-pressure side is for to point to this side bus from transformer; In, the direction component of each outlet of low-voltage bus bar is to point to outlet from bus; The direction component at bus place is to point to bus connection switch from protected bus.Under this regulation; in the system during fault of any one position; the operate condition of orientation measurement element all with the single-side power situation under the operate condition of overcurrent element in full accord; thereby by the Compare Logic shown in Fig. 4,5,6; can judge location of fault apace equally, finish relaying protection function fast.
Claims (2)
1, the relay protecting method of a kind of step-down transformer and mesolow side bus thereof is characterized in that:
(1) measuring component that can reflect fault direction in the outlet and the installing of bar coupler place of each side of transformer, middle voltage bus bar: the mesolow side at transformer does not all have under the situation of power supply, with by escaping overcurrent element that maximum load current adjusts as measuring component; There are power supply or mesolow side all to have under the situation of power supply at medium voltage side or low-pressure side, use direction component as measuring component in the outlet of side that power supply is arranged and connection power supply;
(2) positive direction of regulation transformer high-voltage side direction element is for to point to protected transformer by high voltage bus, the positive direction of mesolow side direction element is pointed to middle voltage bus bar by protected transformer, the positive direction of outlet direction component is pointed to circuit by bus, and the bus prescription points to another bus to the positive direction of element by protected bus;
(3) when high-pressure side measuring component action and the measuring component of mesolow side when all being failure to actuate is judged as power transformer interior fault;
When (4) measuring component central, the low-pressure side either side moves, just be judged as this side fault: if the measuring component at each outlet of this side bus and network interconnecting circuit place all is failure to actuate, be judged as this side bus fault, all electric power incoming lines that the quick tripping of protection action links to each other with this bus; When the measuring component at arbitrary outlet or network interconnecting circuit place moves; be judged as this outlet or another busbar fault; starting backup protection logic, under the situation of outlet, female connection protection or circuit breaker tripping, the time-delay tripping is connected all electric power incoming lines on this side bus.
2, the relay protecting method of a kind of step-down transformer according to claim 1 and mesolow side bus thereof is characterized in that: the action status information of each side measuring component transmits by high-speed communication network in the transformer station or direct physical line.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2005100439575A CN100359775C (en) | 2005-06-28 | 2005-06-28 | Step down transformer and relay protection method of middle low voltage side bus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2005100439575A CN100359775C (en) | 2005-06-28 | 2005-06-28 | Step down transformer and relay protection method of middle low voltage side bus |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1725590A true CN1725590A (en) | 2006-01-25 |
| CN100359775C CN100359775C (en) | 2008-01-02 |
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| Application Number | Title | Priority Date | Filing Date |
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| CNB2005100439575A Expired - Fee Related CN100359775C (en) | 2005-06-28 | 2005-06-28 | Step down transformer and relay protection method of middle low voltage side bus |
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| CN100440671C (en) * | 2006-10-16 | 2008-12-03 | 北京交通大学 | Integrated protection system based on multiple traditional protection technologies |
| CN100448132C (en) * | 2006-06-13 | 2008-12-31 | 北京交通大学 | Integrated protection system based on electric current principle |
| CN101917064A (en) * | 2010-08-05 | 2010-12-15 | 河南省电力公司许昌供电公司 | Back-up protection processing method of digital substation transformer based on GOOSE mode |
| CN101534004B (en) * | 2008-03-10 | 2011-06-22 | 王锐 | Method for distinguishing failure and tripping of high-voltage short-distance double-circuit chain-type power network |
| CN102946086A (en) * | 2012-10-29 | 2013-02-27 | 中国电力科学研究院 | Transformer protection realizing method based on multi-dimensional information |
| CN103633619A (en) * | 2013-12-19 | 2014-03-12 | 国家电网公司 | Cross-interval shared information-based method for main-transformer backup protection accelerated tripping operation based on |
| CN104078934A (en) * | 2014-07-15 | 2014-10-01 | 国家电网公司 | Transformer differential current protection mis-operation preventing relay protection method |
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| CN104614616A (en) * | 2015-02-05 | 2015-05-13 | 华北电力科学研究院有限责任公司 | Match detection method and device of generator-transformer unit protection setting value and excitation limiter setting value |
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| JP3184459B2 (en) * | 1996-08-01 | 2001-07-09 | 株式会社日立製作所 | Power receiving protection device |
| JP3169849B2 (en) * | 1997-02-19 | 2001-05-28 | 株式会社日立製作所 | Spot network substation protection equipment |
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| CN2458799Y (en) * | 2000-12-18 | 2001-11-07 | 王英男 | Current locking type bus protector |
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| CN100448132C (en) * | 2006-06-13 | 2008-12-31 | 北京交通大学 | Integrated protection system based on electric current principle |
| CN100440671C (en) * | 2006-10-16 | 2008-12-03 | 北京交通大学 | Integrated protection system based on multiple traditional protection technologies |
| CN101534004B (en) * | 2008-03-10 | 2011-06-22 | 王锐 | Method for distinguishing failure and tripping of high-voltage short-distance double-circuit chain-type power network |
| CN101917064A (en) * | 2010-08-05 | 2010-12-15 | 河南省电力公司许昌供电公司 | Back-up protection processing method of digital substation transformer based on GOOSE mode |
| CN103208753B (en) * | 2012-01-13 | 2015-09-16 | 包红旗 | A kind of vehicle-mounted removable transformer station |
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| CN104395767A (en) * | 2012-07-03 | 2015-03-04 | 西门子公司 | Detection of a fault direction in medium voltage power supply networks |
| CN102946086A (en) * | 2012-10-29 | 2013-02-27 | 中国电力科学研究院 | Transformer protection realizing method based on multi-dimensional information |
| CN102946086B (en) * | 2012-10-29 | 2015-04-29 | 中国电力科学研究院 | Transformer protection realizing method based on multi-dimensional information |
| CN103633619A (en) * | 2013-12-19 | 2014-03-12 | 国家电网公司 | Cross-interval shared information-based method for main-transformer backup protection accelerated tripping operation based on |
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| CN104092186B (en) * | 2014-07-15 | 2017-02-15 | 国家电网公司 | Thee-phase three-winding transformer fault relay protection method based on sudden changes of positive sequence currents |
| CN104078934B (en) * | 2014-07-15 | 2017-01-18 | 国家电网公司 | Transformer differential current protection device mis-operation preventing relay protection method |
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| CN105137282B (en) * | 2015-08-19 | 2018-01-12 | 国网山东省电力公司检修公司 | Line bus integration back-up protection method based on fault direction longitudinal comparison |
| CN105137282A (en) * | 2015-08-19 | 2015-12-09 | 国网山东省电力公司检修公司 | Line bus integrated backup protection method using pilot comparison principle based on the fault direction |
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| CN105510731B (en) * | 2015-11-26 | 2018-04-20 | 国网辽宁省电力有限公司大连供电公司 | Power transformer medium voltage side power grid parallel resonance detects alarm method and system |
| CN105548810A (en) * | 2015-12-21 | 2016-05-04 | 国家电网公司 | Fault air chamber positioning method and device of buses |
| CN105548810B (en) * | 2015-12-21 | 2018-06-12 | 国家电网公司 | A kind of bus-bar fault gas chamber localization method and device |
| CN105790218A (en) * | 2016-04-25 | 2016-07-20 | 国网江苏省电力公司无锡供电公司 | Main transformer backup protection combined voltage blocking system and method for preventing miss operation |
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