CN104459578B - The remanent magnetism method of estimation of Yyn0 type three-phase group formula transformator non-faulting tripping operations - Google Patents
The remanent magnetism method of estimation of Yyn0 type three-phase group formula transformator non-faulting tripping operations Download PDFInfo
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Abstract
The invention discloses a kind of remanent magnetism method of estimation of Yyn0 types three-phase group formula transformator non-faulting tripping operation, first, signal pickup assembly carries out sampling to the voltage current waveform of Yyn0 type three-phase group formula transformators by transformer and obtains voltage x current instantaneous value, the plural form of each electric parameters is obtained by fourier algorithm, and then obtains power-factor angle and iron core stable state magnetic flux peak value；Then, the three-phase current waveform for being obtained according to sampling, it is determined that first disconnected phase and first disconnected phase drop-out voltage phase angle；Finally, the relation estimation tri-phase iron core remanent magnetism according to the situation of change of winding voltage during separating brake and its with iron core magnetic flux；The method need to only sample Yyn0 type three-phase group formula transformer station high-voltage side bus when three-phase voltage current waveform, the power-factor angle and iron core stable state magnetic flux peak value under steady-state operation is obtained by data processing, iron core remanent magnetism can be estimated accordingly, and relevant parameter is easily obtained, in that context it may be convenient in estimating for Practical Project.
Description
Technical field
The invention belongs to transformator remanent magnetism method of estimation technical field, and in particular to a kind of Yyn0 types three-phase group formula transformator
The remanent magnetism method of estimation of non-faulting tripping operation.
Background technology
Yyn0 type three-phase group formula transformators are made up of three single-phase transformers, and iron core is mainly by silicon steel sheet stack into former secondary
The star-like connection of winding and secondary neutral ground.As each phase magnetic flux is closed along respective magnetic circuit, thus its magnetic circuit system each other without
Close, in one timing of supply frequency and umber of turn, each phase iron core magnetic flux is determined (to ignore coil resistance and leakage by winding applied voltage
Magnetic flux).
As stalloy belongs to ferromagnetic material, there are hysteresis, after transformator separating brake, external magnetic field revocation, ferromagnetics
Remain to keep original part magnetic, make transformer fe in-core leave part magnetic flux, the magnetic flux is referred to as iron core remanent magnetism.Therefore can be approximate
After thinking transformator separating brake, over time not substantially, remanent magnetism is approximately equal to separating brake moment iron core magnetic flux to remanent magnetism.Yyn0 types
During normal operation, former limit three-phase current is equal in magnitude in three-phase symmetrical system for three-phase group formula transformator, 120 ° of phase place mutual deviation, by
Natural disjunction when each phase chopper is in current over-zero, therefore three-phase separating brake moment non-synchronous, the process will cause to power up outside winding
The change of pressure, and then affect iron core remanent magnetism.And in transformer during no-load closing, due to core material excitation property have it is non-linear
Characteristic, is affected by iron core remanent magnetism and breaker closing phase angle, is likely to result in the saturation of iron core, caused transformator in voltage jump
Side produces very big exciting current, and 6～8 times of the maximum reachable rated current of its numerical value, this electric current is known as transformator
Excitation surge current.As excitation surge current amplitude is very big and flows only through transformator side, Differential Protection of Transformer will be caused to produce very
Big difference stream, causes differential protection misoperation to trip, makes put into operation for transformator repeatedly fail；The very big excitation surge current of numerical value can also
Cause transformator and chopper because electric power is excessive and impaired；Excitation surge current is also possible to neighbouring other transformer stations of induction etc. and transports
Capable transformator produces " and echo surge current " and mistrip, causes large-area power-cuts；A large amount of harmonic waves therein are to the electrical network quality of power supply
Will also result in serious pollution.
Phase selection switch technology is that a kind of novel electric power apparatus for proposing with the development of switching technique close means, its
The principle for suppressing excitation surge current is to select suitable switching-on phase, control chopper sound to touch according to the remanent magnetism in separating brake back core
Head carries out switch at the designated phase angle moment of system voltage or current waveform and closes, and when alloing combined floodgate, remanent magnetism and magnetic bias are approximate
Cancel out each other, so as to avoid the supersaturation of transformer core magnetic flux, fundamentally reach weaken excitation surge current purpose.
Existing various traditional counting models with regard to remanent magnetism or magnetic field include Product models, Preisach model,
Stoner-Wohlfarth models, but model above computational methods are directed to the parameter that part not directly measures, and utilize
Software emulation transformator remanent magnetism requires to be compared system work behavior accurate simulation, and model buildings are complex, therefore
In the concrete estimation of transformer core remanent magnetism, practicality is little.
The content of the invention
In order to solve the problems, such as above-mentioned prior art, the present invention provides a kind of Yyn0 types three-phase group formula transformator non-event
Barrier tripping operation remanent magnetism method of estimation, the method need to only sample Yyn0 type three-phase group formula transformer station high-voltage side bus when three-phase voltage current ripple
Shape, obtains the power-factor angle and iron core stable state magnetic flux peak value under steady-state operation, you can estimate iron core accordingly by data processing
Remanent magnetism, relevant parameter are easily obtained, in that context it may be convenient in estimating for Practical Project.
In order to achieve the above object, the present invention is adopted the following technical scheme that：
The remanent magnetism method of estimation of Yyn0 type three-phase group formula transformator non-faulting tripping operations, comprises the steps：
Step 1：During Yyn0 type three-phase group formula transformer station high-voltage side bus, signal pickup assembly is by transformer to Yyn0 type three-phase groups
The voltage current waveform of formula transformator is sampled, and obtains voltage x current instantaneous value；
Step 2：Yyn0 type three-phase group formula transformator stable state three-phase voltages, electric current plural form are obtained by fourier algorithm,
Obtain power-factor angleAnd iron core stable state magnetic flux peak value φm, the iron core stable state magnetic flux peak valueWherein：UmRepresent
Phase voltage amplitude, N represent umber of turn, and ω is system angular frequency；
Step 3：According to the three-phase current waveform that step 1 sampling is obtained, it is determined that first disconnected phase and the disconnected phase voltage phase angles of head
OrFirst the breaking mutually refers to the phase for disconnecting first, i.e., when the electric current of certain phase is reduced to zero first and keeps constant, then
Disconnected phase headed by the phase；
Step 4：Estimation tri-phase iron core remanent magnetism
Assume that first breaking be mutually A phases, and first disconnected phase voltage phase angle is δ, according to knowable to formula (7), A phases cut-off moment tri-phase iron core
Magnetic flux φa、φb、φcAs shown in formula (8)；
A phases disconnect after three-phase windings voltage uA'X、uBY、uCZAs shown in formula (9), three-phase current iA、iB、iCSuch as formula (10) institute
Show, according to the law of electromagnetic induction, magnetic flux φ is sensed in advance by the three-phase that the voltage is produceday、φby、φcyFor formula (11)；
According to continuity of magnetic flux theorem, A phases disconnect moment magnetic flux and cannot be mutated, and will produce three skews as shown in formula (12)
Magnetic flux φap、φbp、φcpTo offset the pre- sensing magnetic flux at the moment；
Therefore after A phases disconnect, tri-phase iron core magnetic flux is (8), (11), (12) formula sum, shown in abbreviation such as formula (13)；
According to formula (10), B, C phase will the electric current zero passage nature disjunction simultaneously in delayed 90 ° of electrical angles of A phases；By ω t=δ+
90 ° are brought into formula (13), can obtain tri-phase iron core remanent magnetism φar、φbr、φcrFor formula (14)；
As three-phase system has a symmetry, thus break headed by B, C phase phase when, it is first it is disconnected mutually and another biphase flux change rule with
Above-mentioned situation is identical, can obtain first disconnected phase remanent magnetism expression formula accordingly, as shown in formula (15)；
φsd=φm sin(δ-90°) (15)
During normal operation, the phase remanent magnetism of advanced first disconnected 120 ° of the phase of voltage-phase is formula (16)；
During normal operation, the phase remanent magnetism of delayed first disconnected 120 ° of the phase of voltage-phase is formula (17)；
Compared to the prior art compared with the present invention possesses following advantage：
1st, relevant parameter is easily obtained.I.e. all parameters of remanent magnetism method of estimation can pass through direct measurement or calculate indirectly to obtain
.
2. the system model of complexity, compared to software emulation Yyn0 type three-phase group formula transformator remanent magnetism, need not be built, it is convenient
Estimate for engineering.
Description of the drawings
Fig. 1 is voltage-current relationship figure.
Fig. 2 is Yyn0 type three-phase group formula transformator connection group schematic diagrams.
Fig. 3 is phantom equivalent circuit diagram.
Fig. 4 is estimation magnetic flux and emulation flux waveformses comparison diagram.
Specific embodiment
The present invention is described in detail with reference to the accompanying drawings and detailed description：
During transformer station high-voltage side bus, signal pickup assembly passes through voltage x current ripple of the transformer to Yyn0 type three-phase group formula transformators
Shape carries out sampling and obtains voltage x current instantaneous value, obtains stable state three-phase voltage plural form by fourier algorithmAnd electric current plural formSuch as formula (1), (2).Wherein UmRepresent phase voltage amplitude, α
Represent A phase voltage phase angles, ImLine current amplitude is represented, β represents A phase current phase angles, and power-factor angle is each phase voltage with electricity
Stream phase angle difference, therefore
If A phase voltage phase angle α=0 °, stable state three-phase voltage time-domain expression u can be obtained by (1), (2)A(t)、uB(t)、uC
(t), and electric current time-domain expression iA(t)、iB(t)、iC(t), such as formula (3), (4).
Wherein ω is system angular frequency.
As transformer primary side is coupled for Y, therefore each phase winding voltage is phase voltage during normal operation, as shown in formula (5).
According to Faraday law of electromagnetic induction,
Wherein u represents winding voltage, and φ represents iron core magnetic flux, and N represents umber of turn.
Then tri-phase iron core magnetic flux φa、φb、φcIt is represented by
Wherein iron core stable state magnetic flux peak value is
In Fig. 1, u represents former limit phase voltage, and i represents phase current, as during separating brake, chopper will divide naturally in current over-zero
It is disconnected, therefore first disconnected phase voltage phase angle isOr
Assume that first breaking be mutually A phases, andWhen cut-off, according to formula (7) understand, A phases cut-off moment tri-phase iron core magnetic flux
As shown in formula (8).Cut-off rear electric parameters to be analyzed with symmetrical component method.For Yyn0 type group formula three-phase transformers, such as Fig. 2 institutes
Show, its former limit does not have zero-sequence current path, therefore positive sequence impedance is approximately equal to negative sequence impedance in being believed that sequence net, and zero sequence impedance is infinite
Greatly, A phases can be obtained accordingly and cut-off rear three-phase windings voltage, electric current, as shown in formula (9), (10).
According to the law of electromagnetic induction, the three-phase for cut-offfing rear three-phase windings voltage generation by A phases senses magnetic flux φ in advanceay、φby、
φcyFor formula (11)；
According to continuity of magnetic flux theorem, the moment magnetic flux cannot be mutated, will produce magnetic bias as shown in formula (12) pass to
Disappear the pre- sensing magnetic flux at the moment.
Therefore after A phases disconnect, tri-phase iron core magnetic flux is (8), (11), (12) formula sum, shown in abbreviation such as formula (13).
According to formula (10), B, C phase will the electric current zero passage nature disjunction simultaneously in delayed 90 ° of electrical angles of A phases.By ω t=δ+
90 ° are brought into formula (13), can be obtained tri-phase iron core remanent magnetism and are
As three-phase system has a symmetry, thus break headed by B, C phase phase when, it is first it is disconnected mutually and another biphase flux change rule with
Above-mentioned situation is identical, can obtain first disconnected phase remanent magnetism expression formula accordingly, as shown in formula (15).
φsd=φm sin(δ-90°) (15)
During normal operation, the phase remanent magnetism of advanced first disconnected 120 ° of the phase of voltage-phase is
During normal operation, the phase remanent magnetism of delayed first disconnected 120 ° of the phase of voltage-phase is
Embodiment
Phantom as shown in Figure 3 is built, in figure：XLLine impedance is represented, TV represents voltage transformer, and TA represents electricity
Current transformer, QK represent three-phase breaker.Sub-switching operation is carried out to three-phase breaker QK, signal pickup assembly is adopted by TA and TV
Collection three-phase voltage current waveform.In this emulation, power-factor angleIron core stable state magnetic flux peak value φm=47.83wb*
N, first breaking be mutually B phases, first disconnected phase angleEach phase separating brake moment is as shown in Figure 4.Using formula (15), (16) and (17) fitting point
Tri-phase iron core magnetic flux during lock, is compared with emulation magnetic flux, as can be seen from the figure：Estimate during separating brake that magnetic flux can be with
Preferably Curve fitting simulation magnetic flux, after three-phase equal separating brake, estimates error very little between magnetic flux and emulation magnetic flux, it is seen that the method can have
Effect estimates tri-phase iron core remanent magnetism.
The specific embodiment of the present invention is described above in association with accompanying drawing, but these explanations can not be understood to limit
The scope of the present invention, protection scope of the present invention is limited by appended claims, any in the claims in the present invention base
Change on plinth is all protection scope of the present invention.
Claims (1)
- The remanent magnetism method of estimation of 1.Yyn0 type three-phase group formula transformator non-faulting tripping operations, it is characterised in that：Comprise the steps：Step 1：During Yyn0 type three-phase group formula transformer station high-voltage side bus, signal pickup assembly is become to Yyn0 type three-phase groups formula by transformer The voltage current waveform of depressor is sampled, and obtains voltage x current instantaneous value；Step 2：Yyn0 type three-phase group formula transformator stable state three-phase voltages, electric current plural form are obtained by fourier algorithm, is obtained Power-factor angleAnd iron core stable state magnetic flux peak value φm, the iron core stable state magnetic flux peak valueWherein：UmRepresent mutually electricity Pressure amplitude value, N represent umber of turn, and ω is system angular frequency；Step 3：According to the three-phase current waveform that step 1 sampling is obtained, it is determined that first disconnected phase and the disconnected phase voltage phase angles of headOrFirst the breaking mutually refers to the phase for disconnecting first, i.e., when the electric current of certain phase is reduced to zero first and keeps constant, then should Disconnected phase headed by phase；Step 4：Estimation tri-phase iron core remanent magnetismAssume that first breaking be mutually A phases, and first disconnected phase voltage phase angle is δ, according to knowable to formula (7), A phases cut-off moment tri-phase iron core magnetic flux φa、φb、φcAs shown in formula (8)；A phases disconnect after three-phase windings voltage uA'X、uBY、uCZAs shown in formula (9), three-phase current iA、iB、iCAs shown in formula (10), root According to the law of electromagnetic induction, magnetic flux φ is sensed in advance by the three-phase that the voltage is produceday、φby、φcyFor formula (11)；According to continuity of magnetic flux theorem, A phases disconnect moment magnetic flux and cannot be mutated, and will produce the three-phase magnetic bias as shown in formula (12) and lead to φap、φbp、φcpTo offset the pre- sensing magnetic flux at the moment；Therefore after A phases disconnect, tri-phase iron core magnetic flux is (8), (11), (12) formula sum, shown in abbreviation such as formula (13)；According to formula (10), B, C phase will the electric current zero passage nature disjunction simultaneously in delayed 90 ° of electrical angles of A phases；By ω t=+90 ° of bands of δ Enter formula (13), tri-phase iron core remanent magnetism φ can be obtainedar、φbr、φcrFor formula (14)；As three-phase system has a symmetry, thus break headed by B, C phase phase when, it is first it is disconnected mutually and another biphase flux change rule with it is above-mentioned Situation is identical, can obtain first disconnected phase remanent magnetism expression formula accordingly, as shown in formula (15)；φsd=φm sin(δ-90°) (15)During normal operation, the phase remanent magnetism of advanced first disconnected 120 ° of the phase of voltage-phase is formula (16)；During normal operation, the phase remanent magnetism of delayed first disconnected 120 ° of the phase of voltage-phase is formula (17)；
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| CN107482600B (en) * | 2017-07-18 | 2019-01-08 | 西安交通大学 | Yyn0 type three-phase group formula transformer drops excitation surge current suppressing method |
| CN109038491B (en) * | 2018-07-05 | 2020-04-17 | 内蒙古电力(集团)有限责任公司内蒙古电力科学研究院分公司 | Large power transformer magnetizing inrush current suppression method |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19641116A1 (en) * | 1996-10-05 | 1998-04-09 | Christoph Ploetner | Detection process for transformer core remanence flux |
| CN101561480A (en) * | 2009-05-22 | 2009-10-21 | 哈尔滨工业大学 | Method for measuring parameter of magnetic characteristic of permanent magnet |
| CN103105594A (en) * | 2013-01-24 | 2013-05-15 | 江苏省电力公司电力科学研究院 | Current mutual inductor residual magnetism detection method based on small-signal gradient mapping |
| CN103176147A (en) * | 2013-03-13 | 2013-06-26 | 江苏省电力公司电力科学研究院 | Current transformer remanence measurement system and method |
| JP5299109B2 (en) * | 2009-06-17 | 2013-09-25 | 三菱電機株式会社 | Residual magnetic flux measuring device, residual magnetic flux measuring method, and circuit breaker synchronous switching control device |
| CN103675728A (en) * | 2013-11-22 | 2014-03-26 | 河北工业大学 | Closed magnetic circuit magnetic core residual magnetism measuring method |
| CN103913710A (en) * | 2014-03-28 | 2014-07-09 | 云南电力试验研究院（集团）有限公司电力研究院 | Method for measuring residual magnetic flux density of iron core of transformer |
| CN103986385A (en) * | 2014-05-21 | 2014-08-13 | 西安交通大学 | Method for restraining no-load closing magnetizing inrush current of transformer |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5646237B2 (en) * | 2010-07-26 | 2014-12-24 | 株式会社東芝 | Residual magnetic flux estimation method and residual magnetic flux estimation device for transformer |
| US9008982B2 (en) * | 2012-03-09 | 2015-04-14 | Schweitzer Engineering Laboratories, Inc. | Systems and methods for determining residual flux in a power transformer |
-
2014
- 2014-12-02 CN CN201410722789.1A patent/CN104459578B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19641116A1 (en) * | 1996-10-05 | 1998-04-09 | Christoph Ploetner | Detection process for transformer core remanence flux |
| CN101561480A (en) * | 2009-05-22 | 2009-10-21 | 哈尔滨工业大学 | Method for measuring parameter of magnetic characteristic of permanent magnet |
| JP5299109B2 (en) * | 2009-06-17 | 2013-09-25 | 三菱電機株式会社 | Residual magnetic flux measuring device, residual magnetic flux measuring method, and circuit breaker synchronous switching control device |
| CN103105594A (en) * | 2013-01-24 | 2013-05-15 | 江苏省电力公司电力科学研究院 | Current mutual inductor residual magnetism detection method based on small-signal gradient mapping |
| CN103176147A (en) * | 2013-03-13 | 2013-06-26 | 江苏省电力公司电力科学研究院 | Current transformer remanence measurement system and method |
| CN103675728A (en) * | 2013-11-22 | 2014-03-26 | 河北工业大学 | Closed magnetic circuit magnetic core residual magnetism measuring method |
| CN103913710A (en) * | 2014-03-28 | 2014-07-09 | 云南电力试验研究院（集团）有限公司电力研究院 | Method for measuring residual magnetic flux density of iron core of transformer |
| CN103986385A (en) * | 2014-05-21 | 2014-08-13 | 西安交通大学 | Method for restraining no-load closing magnetizing inrush current of transformer |
Non-Patent Citations (2)
| Title |
|---|
| 变压器铁心剩磁估量;邢运民 等;《电网技术》;20110228;第35卷(第2期);第169-172页 * |
| 计及剩磁的变压器励磁涌流的仿真研究;黄金 等;《变压器》;20091130;第46卷(第11期);第40-43页 * |
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