CN108767826A - Do not demagnetize converter power transformer air-drop excitation surge current suppressing method after straight resistance experiment - Google Patents
Do not demagnetize converter power transformer air-drop excitation surge current suppressing method after straight resistance experiment Download PDFInfo
- Publication number
- CN108767826A CN108767826A CN201810615879.9A CN201810615879A CN108767826A CN 108767826 A CN108767826 A CN 108767826A CN 201810615879 A CN201810615879 A CN 201810615879A CN 108767826 A CN108767826 A CN 108767826A
- Authority
- CN
- China
- Prior art keywords
- straight resistance
- phase
- converter power
- transformer
- power transformer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H9/00—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection
- H02H9/001—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection limiting speed of change of electric quantities, e.g. soft switching on or off
- H02H9/002—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection limiting speed of change of electric quantities, e.g. soft switching on or off limiting inrush current on switching on of inductive loads subjected to remanence, e.g. transformers
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
- H02H7/04—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for transformers
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H9/00—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection
- H02H9/02—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess current
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/36—Arrangements for transfer of electric power between ac networks via a high-tension dc link
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/60—Arrangements for transfer of electric power between AC networks or generators via a high voltage DC link [HVCD]
Abstract
The invention discloses not demagnetizing after a kind of straight resistance experiment, converter power transformer drops excitation surge current suppressing method, this method is adjusted to the straight resistance test connection of converter power transformer tradition, on the basis of becoming the reversed straight resistance experiment of the separate progress in part to star, direction is tested according to directly resistance and sequence determines converter power transformer switching order and each phase combined floodgate voltage phase angle；This method is not when Overhaul site has iron core demagnetization condition, it only needs to adjust straight resistance experiment direction and carries out phase selection position combined floodgate accordingly, do not demagnetize converter power transformer air-drop excitation surge current after can effectively inhibiting straight resistance to test, and relevant parameter easily obtains, it may be convenient in Practical Project.
Description
Technical field
The invention belongs to power system main equipment technical field of relay protection, and in particular to a kind of based on the straight of phase selection
The converter power transformer that do not demagnetize after resistance experiment encourages air-drop magnetic surge suppression method.
Background technology
Converter power transformer is one of the core equipment in DC transmission engineering, is broken down after damaging since maintenance is difficult
Degree is big, the time between overhauls(TBO) is long, can not only influence the normal operation of electric system, or even can cause immeasurable economic loss and society
It can influence.Converter power transformer iron core magnetic flux when zero load is put into cannot be mutated, and the transient state magnetic flux generated due to voltage jump can
Iron core can be caused to be saturated, it will to generate the prodigious electric current of numerical value in the side of transformer voltage mutation, which is referred to as
Excitation surge current.Since iron core flux density is higher, saturation point is relatively low while winding resistance is smaller, and converter power transformer excitation surge current shows
The highly attenuating slow feature of amplitude influences to be much larger than conventional electric power transformer caused by system normal operation, it is therefore necessary to adopt
Measure is taken to inhibit it.
The major influence factors of excitation surge current are iron core magnetization characteristic, iron core remanent magnetism and switching voltage phase angle.Change of current transformation
Device often carries out straight resistance experimental test during maintenance, and there are very by magnetizing each phase iron core to saturation for the test
Big remanent magnetism directly carries out its iron core magnetic flux when zero load puts into operation and is likely to be breached three times if being handled later without iron core demagnetization
Rated flux causes the great excitation surge current of amplitude, the serious safe and stable operation for destroying high voltage ac/dc system.If therefore existing
When field does not have iron core demagnetization condition, using the generation of transient state magnetic flux during phase selection position combined floodgate means control idle-loaded switching-on, mitigate
The degree of saturation of iron core magnetic flux exchanges the successful air-drop of rheology and the normal operation of system with important to inhibit excitation surge current
Meaning.
The key that phase selection switch technology drops excitation surge current applied to the converter power transformer that do not demagnetize after the straight resistance experiment of inhibition exists
In selecting best switching-on phase angle, that is, include the analysis and alternate conjunction to directly hindering converter power transformer iron core remanent magnetism information after experiment
The cooperation of lock sequence.Unlike conventional transformer, 12 pulse conversion transformer of monopole is by organizing Circuit Breaker Switching together
It is coupled two groups of converter power transformer group paired runnings that pattern is respectively YNyn0 and YNd11 to constitute.To each single-phase change of current become successively into
After the straight resistance experiment of row, iron core remanent magnetism difference causes two best closing phase angles of changes of current change of same phase different, mutual when inphase angle closes
It is affected.Therefore the present invention has fully considered after straight resistance experiment between remanent magnetism polarity and change of current change group and inter-phase electromagnetic couples shadow
It rings, gives one kind for converter power transformer phase selection method of not demagnetizing after straight resistance experiment, this method can be very good to inhibit
The excitation surge current that transformer during no-load closing generates.
Invention content
In order to solve the above-mentioned problems of the prior art, the present invention provides change of current transformation of not demagnetizing after the straight resistance of one kind is tested
Device drops excitation surge current suppressing method, and this method is not when Overhaul site has iron core demagnetization condition, it is only necessary to become part phase to star
On the basis of reversed directly Jin Hang not hindering experiment, converter power transformer switching order and each phase are determined according to straight resistance experiment direction and sequentially
Switching voltage phase angle, you can not demagnetize converter power transformer air-drop excitation surge current after effectively inhibiting straight resistance to test, and relevant parameter easily obtains
It takes, it may be convenient in Practical Project.
In order to achieve the above object, the present invention adopts the following technical scheme that：
1, do not demagnetize converter power transformer air-drop excitation surge current suppressing method after straight resistance experiment, includes the following steps：
Step 1：Each single-phase transformer is become to the angle in 12 pulse conversion transformer of monopole and carries out forward direction successively in net side
Straight resistance experiment, the separate M that record is finally tested；Direct resistance metering instrument positive terminal is connect net by the positive straight resistance experiment
Side winding end of incoming cables, negative terminal connect source side winding ground terminal；
Step 2：Become each single-phase transformer to the star in 12 pulse conversion transformer of monopole directly to be hindered successively in net side
Experiment, wherein M phases carry out positive straight resistance experiment, remaining two-phase carries out reversed straight resistance experiment；The reversed straight resistance experiment will be straight
It hinders the positive and negative end of tester and exchanges wiring, the DC current for enabling net winding inflow direction opposite；
Step 3：It closes a floodgate first to M phases after receiving switching signal, switching voltage angle is α1=180 °；Be delayed 2~3 cycles
It closes a floodgate simultaneously to remaining two-phase afterwards, switching voltage angle is α2=0 ° or α2=180 °, the combined floodgate angle with M phase voltages just
It is reference point to zero crossing.
The 12 pulse conversion transformer of monopole of the step 1 is by same group of Circuit Breaker Switching, and the mode of connection is respectively
The converter power transformer group that two groups of parallel operation of transformers of YNyn0 and YNd11 are constituted, primary side is connect with AC system, for step
Rapid 1 net side, secondary side are connect with converter valve, referred to as valve side.
Step 1 angle becomes the transformer group that the mode of connection in 12 pulse conversion transformer of monopole is YNd11.
Step 2 star becomes the transformer group that the mode of connection in 12 pulse conversion transformer of monopole is YNyn0.
Compared to the prior art compared with the present invention has following advantage：
1, relevant parameter easily obtains.I.e. all parameters of excitation surge current suppressing method can be by directly measuring acquisition.
2. compared to traditional converter power transformer excitation surge current Restrain measurement, this method fully considers and has adjusted straight resistance experiment
Iron core remanent magnetism size and polarity afterwards when not having iron core demagnetization condition at the scene, directly carry out phase selection position idle-loaded switching-on, operation letter
Single excitation surge current inhibition simultaneously is more preferable.
Description of the drawings
Fig. 1 is that transformer directly hinders experiment equivalent circuit diagram.
Fig. 2 is 12 pulse conversion transformer connection figure of monopole.
Iron core magnetic flux variation diagram during Fig. 3 is phase selection.
Fig. 4 is overall plan figure.
Fig. 5 is simulation model figure.
Fig. 6 is the switching current oscillogram that emulation obtains.
Fig. 7 is the switching voltage oscillogram that emulation obtains.
Specific implementation mode
The present invention is described in detail with reference to the accompanying drawings and detailed description：
Single-phase transformer as shown in Figure 1 directly hinders experiment equivalent circuit, and L and R are respectively transformer winding equivalent inductance and electricity
Resistance, i is loop current, and E is direct voltage source, can row loop-voltage equation have：
It solves
In formula：T=L/R indicates down slope time constant.
It can be seen that k combined floodgates primary iron core is unsaturated, winding equivalent inductance is larger to cause its partial pressure larger, and test loop is equivalent to
Winding charge circuit, iron core magnetic flux constantly rise, and electric current gradually increases.Until iron core magnetic flux is saturated, winding equivalent inductance is almost
0 is sported, loop current increases to i=E/R suddenly, has di/dt=0 according to formula (1) at this time, therefore loop current reaches stable state not
Increase again, D.C. resistance R can be sought using DC voltage E and steady-state current i.As the above analysis, straight resistance, which is tested, is
Magnetize iron core to the process of saturation, thus after testing remanent magnetism close to saturation flux Φs, according to the straight resistance of field experience generally estimation
Remanent magnetism is 0.85p.u. after experiment.
12 pulse conversion transformer device structure of monopole and the method for operation are as shown in Fig. 2, comprising by organizing together Circuit Breaker Switching
It is coupled two groups of changes of current that pattern is respectively YNyn0 (hereinafter referred to as star change) and YNd11 (hereinafter referred to as angle change) and becomes paired running, often
The group change of current becomes tri-phase iron core independence, and independent operation is carried out to every phase iron core during straight resistance experiment.For angle becomes, due to valve
Side (secondary side and converter valve connecting side) Δ winding can not be unlocked, and be sent out when remaining two-phase iron core magnetic is colluded when certain mutually carries out directly hindering experiment
Changing can obtain tri-phase iron core magnetic flux by voltage integrating meter and be constantly equal to 0 in view of Δ winding is by three-phase windings voltage and to clamp down on be 0,
That is iron core balance of flux.Assuming that A phases iron core finally carries out straight resistance experiment, then angle becomes remanent magnetism as [0.85-0.425-0.425]
p.u..And for star change, tri-phase iron core magnetic flux is independent of each other, if carrying out positive straight resistance experiment, three-phase remanent magnetism is equal
And polarity is identical, and zero sequence fluxes in hereafter making process is caused greatly to influence transient state flux decay.Become three-phase to reduce star
The unbalanced influence of remanent magnetism is taken and is tested above-mentioned A phases (i.e. angle becomes most end experiment phase) positive straight resistance of progress, B with C phases carry out instead
To the test method of straight resistance experiment (reversal connection of direct resistance metering instrument positive and negative electrode), then remanent magnetism is [0.85-0.85-0.85] after testing
p.u.。
Two changes of current of same phase in view of paired running when putting into operation become by same breaker control combined floodgate, then above-mentioned straight resistance examination
It selects star to become the identical A phases with angle change remanent magnetism after testing first to close a floodgate.If A phase supply voltages are uA(t)=Umsin(ωt+
α), UmIt is primary side winding voltage peak, ω is voltage angular frequency, and α is supply voltage initial phase angle, to A phase transformer source side windings
Row loop-voltage equation is：
Wherein：R is transformer primary circuit equivalent resistance, and i is transformer primary circuit electric current, N1It is net umber of turn,
φAIt is A phase iron core magnetic fluxs；It is often negligible due to transformer primary circuit equivalent resistance R very littles, then have
Enable A phase closing moments be t=0 then has since iron core magnetic flux can not be mutated
φA(0)=ΦrA (5)
Iron core magnetic flux is after convolution (4) closes a floodgate with A phases known to formula (5)
In formula,For stable state magnetic flux peak value, L is equivalent magnetizing inductance.
Enable ΦrA+φmα=0 cos, in conjunction with Analysis ofremanence after straight resistance experiment as a result, the best closing phase angle of A phases known to then is optional
It is selected as
α=arccos (- ΦrA/Φm)=arccos (- 0.85)=150 ° (7)
Then A phases iron core magnetic flux after phase angle combined floodgate is directly entered steady-state operation without being saturated, and excitation surge current obtains
To eliminate.A phases close a floodgate after due to delta windings effect, angle becomes B, C phase valve side winding and generates induced voltage, iron core magnetic flux
It is no longer held at that remanent magnetism is constant, but with the dynamic magnetic flux of A phase flux changes, such as t in Fig. 31~t2It is shown.Since angle becomes three-phase
Magnetic flux balances always, therefore it is the 1/2 of A phases, 180 ° of delayed phase to have B, C phase magnetic flux.
In addition, angle become B, C phase iron core flux change cause its net winding equally to have induced voltage generation, respectively with corresponding phase
Other star becomes net winding and constitutes current loop (shown in Fig. 2 dotted lines) so that star, which becomes B, C phase net winding, exciting current circulation, iron
Core flux synchronous changes.Since two single-phase converter power transformers of every phase paired running are by same Circuit Breaker Switching, net winding
It is connected directly and neutral ground, therefore the source side winding pressure drop of two transformers is identical, that is, has
uyv=udv (8)
Wherein, v=A, B, C；
Both sides integral can obtain iron core flux change and be
Δφyv=Δ φdv (9)
Become stable state iron core magnetic flux with two changes of current of phase to be consistent, it follows that star becomes B, C phase iron core after A phases are closed a floodgate
Flux synchronous changes, such as t in Fig. 31~t2It is shown.At this time since star becomes three-phase initial magnetic flux and not into 0, B, C phase iron core magnetic flux
Consistently greater than angle becomes, and can not determine that exact time so that star becomes and angle becomes iron core magnetic flux (Fig. 3 identical as pre- inducting flux at this time
Shown in middle dotted line), therefore for practical implementation, using approximately equal moment-A phases magnetic flux peak value, that is, voltage over zero to B, C
It mutually closes a floodgate, that is, determines that the best closing phase angle of B, C phase is α '=0 ° or α '=180 °, t in magnetic flux such as Fig. 3 after combined floodgate2Institute after moment
Show.
Fig. 4 is the overall plan figure of the method for the present invention, in figure：XLIndicate that line impedance, TV indicate voltage transformer, TA tables
Show that current transformer, QK indicate three-phase breaker.
Embodiment
Fig. 5 is the simulation model built, and two groups of transformers are three-phase two-simulation transformer group in this simulation model, specified
Voltage is 345/289kV, and rated capacity 1209MVA, rated no-load current is about 2A.Transformer primary is acquired by I, V in Fig. 5
Side winding current and voltage waveform, control switch close at the not inphase angle of voltage waveform, observe primary side winding current waveform.
To simulate remanent magnetism distribution situation after straight resistance is tested, emulation setting angle becomes and star change remanent magnetism is respectively [0.85-0.425-0.425]
And [0.85-0.85-0.85] p.u. p.u..
It closes a floodgate at α=150 ° to A phases first after straight resistance experiment as the above analysis, later in α '=0 ° to B, C phase
It closes a floodgate simultaneously, the voltage current waveform difference emulated is as shown in Figure 6 and Figure 7, it is seen that it is straight that combined floodgate relief angle becomes three-phase current
It taps into and is generated without excitation surge current into stable state, and star change has smaller magnetic bias to generate due to closing moment approximation, iron core goes out after combined floodgate
There is the smaller excitation surge current of amplitude in existing a degree of saturation, B, C phase.
Above-described specific implementation mode has carried out further the purpose of the present invention, technical solution and advantageous effect
It is described in detail, it should be understood that the foregoing is merely the specific implementation mode of the present invention, is not intended to limit the present invention
Protection domain, all within the spirits and principles of the present invention, any modification, equivalent substitution, improvement and etc. done should all include
Within protection scope of the present invention.
Claims (4)
1. do not demagnetize converter power transformer air-drop excitation surge current suppressing method after straight resistance experiment, which is characterized in that include the following steps：
Step 1：Each single-phase transformer is become to the angle in 12 pulse conversion transformer of monopole and carries out positive straight resistance successively in net side
Experiment, the separate M that record is finally tested；The positive straight resistance experiment i.e. by direct resistance metering instrument positive terminal connect net side around
Group end of incoming cables, negative terminal connect source side winding ground terminal；
Step 2：Each single-phase transformer is become to the star in 12 pulse conversion transformer of monopole and carries out directly resistance experiment successively in net side,
Wherein M phases carry out positive straight resistance experiment, remaining two-phase carries out reversed straight resistance experiment；The reversed straight resistance experiment is i.e. by direct resistance metering
The positive and negative end of instrument exchanges wiring, the DC current for enabling net winding inflow direction opposite；
Step 3：It closes a floodgate first to M phases after receiving switching signal, switching voltage angle is α1=150 °；It is right after 2~3 cycles of delay
Remaining two-phase is closed a floodgate simultaneously, and switching voltage angle is α2=0 ° or α2=180 °, the combined floodgate angle is with M phase voltage forward direction mistakes
Zero is reference point.
2. do not demagnetize converter power transformer air-drop excitation surge current suppressing method after straight resistance experiment according to claim 1, special
Sign is that the 12 pulse conversion transformer of monopole described in step 1 is by same group of Circuit Breaker Switching, and the mode of connection is respectively
The converter power transformer group that two groups of parallel operation of transformers of YNyn0 and YNd11 are constituted, primary side is connect with AC system, for step
Rapid 1 net side, secondary side are connect with converter valve, referred to as valve side.
3. do not demagnetize converter power transformer air-drop excitation surge current suppressing method after straight resistance experiment according to claim 1, special
Sign is that angle described in step 1 becomes the transformer group that the mode of connection in 12 pulse conversion transformer of monopole is YNd11.
4. do not demagnetize converter power transformer air-drop excitation surge current suppressing method after straight resistance experiment according to claim 1, special
Sign is that star described in step 2 becomes the transformer group that the mode of connection in 12 pulse conversion transformer of monopole is YNyn0.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810615879.9A CN108767826B (en) | 2018-06-14 | 2018-06-14 | Do not demagnetize converter power transformer air-drop excitation surge current suppressing method after straight resistance test |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810615879.9A CN108767826B (en) | 2018-06-14 | 2018-06-14 | Do not demagnetize converter power transformer air-drop excitation surge current suppressing method after straight resistance test |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108767826A true CN108767826A (en) | 2018-11-06 |
| CN108767826B CN108767826B (en) | 2019-07-12 |
Family
ID=64022156
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810615879.9A Active CN108767826B (en) | 2018-06-14 | 2018-06-14 | Do not demagnetize converter power transformer air-drop excitation surge current suppressing method after straight resistance test |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108767826B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111398881A (en) * | 2020-03-21 | 2020-07-10 | 重庆大学 | One-time solving method for reversible pi model excitation characteristics of transformer based on excitation inrush current |
| CN115347533A (en) * | 2022-10-18 | 2022-11-15 | 保定市英电电力科技有限公司 | Method for reducing excitation inrush current of large transformer |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5172067A (en) * | 1991-05-20 | 1992-12-15 | Commonwealth Edison Company | Apparatus for determining DC resistance in high voltage winding with nonlinear resistance energy dissipation circuit |
| CN101951221A (en) * | 2010-09-25 | 2011-01-19 | 中国南方电网有限责任公司超高压输电公司检修试验中心 | Twelve pulsating commutation transformer and method and circuit for removing residual magnetism thereof |
| CN202142476U (en) * | 2011-07-08 | 2012-02-08 | 保定市金源科技有限公司 | Change-over switch of transformer DC resistor tester |
| CN102759662A (en) * | 2012-07-09 | 2012-10-31 | 中国长江三峡集团公司 | Method for measuring DC (Direct Current) resistances of transformer windings |
| CN105158565A (en) * | 2015-07-22 | 2015-12-16 | 国网山东省电力公司日照供电公司 | Auxiliary apparatus and method for fast testing DC resistance of large power transformer |
| CN107302216A (en) * | 2017-07-18 | 2017-10-27 | 西安交通大学 | YNd11 types three-phase transformer drops excitation surge current suppressing method |
| CN107482600A (en) * | 2017-07-18 | 2017-12-15 | 西安交通大学 | Yyn0 type three-phase group formulas transformer drops excitation surge current suppressing method |
| CN108107384A (en) * | 2017-12-18 | 2018-06-01 | 国网新疆电力公司检修公司 | 750kV auto-transformers directly hinder remanent magnetism amount computational methods after experiment |
-
2018
- 2018-06-14 CN CN201810615879.9A patent/CN108767826B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5172067A (en) * | 1991-05-20 | 1992-12-15 | Commonwealth Edison Company | Apparatus for determining DC resistance in high voltage winding with nonlinear resistance energy dissipation circuit |
| CN101951221A (en) * | 2010-09-25 | 2011-01-19 | 中国南方电网有限责任公司超高压输电公司检修试验中心 | Twelve pulsating commutation transformer and method and circuit for removing residual magnetism thereof |
| CN202142476U (en) * | 2011-07-08 | 2012-02-08 | 保定市金源科技有限公司 | Change-over switch of transformer DC resistor tester |
| CN102759662A (en) * | 2012-07-09 | 2012-10-31 | 中国长江三峡集团公司 | Method for measuring DC (Direct Current) resistances of transformer windings |
| CN105158565A (en) * | 2015-07-22 | 2015-12-16 | 国网山东省电力公司日照供电公司 | Auxiliary apparatus and method for fast testing DC resistance of large power transformer |
| CN107302216A (en) * | 2017-07-18 | 2017-10-27 | 西安交通大学 | YNd11 types three-phase transformer drops excitation surge current suppressing method |
| CN107482600A (en) * | 2017-07-18 | 2017-12-15 | 西安交通大学 | Yyn0 type three-phase group formulas transformer drops excitation surge current suppressing method |
| CN108107384A (en) * | 2017-12-18 | 2018-06-01 | 国网新疆电力公司检修公司 | 750kV auto-transformers directly hinder remanent magnetism amount computational methods after experiment |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111398881A (en) * | 2020-03-21 | 2020-07-10 | 重庆大学 | One-time solving method for reversible pi model excitation characteristics of transformer based on excitation inrush current |
| CN111398881B (en) * | 2020-03-21 | 2023-07-18 | 重庆大学 | One-time solving method for excitation characteristics of reversible pi model of transformer based on excitation surge |
| CN115347533A (en) * | 2022-10-18 | 2022-11-15 | 保定市英电电力科技有限公司 | Method for reducing excitation inrush current of large transformer |
Also Published As
| Publication number | Publication date |
|---|---|
| CN108767826B (en) | 2019-07-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107302216B (en) | YNd11 type three-phase transformers drop excitation surge current suppressing method | |
| Moriconi et al. | An innovative compact saturable-core HTS Fault Current Limiter-development, testing and application to transmission class networks | |
| CN108767826B (en) | Do not demagnetize converter power transformer air-drop excitation surge current suppressing method after straight resistance test | |
| Ko et al. | Analysis on magnetizing characteristics due to peak fault current limiting operation of a modified flux-lock-type SFCL with two magnetic paths | |
| Marx et al. | An introduction to symmetrical components, system modeling and fault calculation | |
| Kumbhar et al. | Analysis of sympathetic inrush phenomena in transformers using coupled field-circuit approach | |
| CN109103860B (en) | Pre-magnetizing method for marine transformer based on series connection of small-capacity transformers | |
| Hu et al. | Characteristic tests and electromagnetic analysis of an HTS partial core transformer | |
| CN107482600B (en) | Yyn0 type three-phase group formula transformer drops excitation surge current suppressing method | |
| CN104483639B (en) | Residual magnetism estimation method for non-fault tripping of YNd11 type three-phase combined transformer | |
| Yamaguchi et al. | Effect of magnetic saturation on the current limiting characteristics of transformer type superconducting fault current limiter | |
| Ahfock et al. | DC magnetisation of transformers | |
| Tishuai et al. | Influence of system transients on the residual flux of three-phase transformers | |
| Yao et al. | Harmonics and reactive power of power transformers with DC bias | |
| Reis et al. | A controlled switching methodology for transformer inrush current elimination: Theory and experimental validation | |
| CN107332212B (en) | The three-phase group formula transformer excitation flow suppressing method to close a floodgate from delta windings side | |
| CN107102229B (en) | Method for realizing transformer model for no-load switching transient calculation | |
| de Castro Cezar et al. | Elimination of inrush current using a new prefluxing method. Application to a single-phase transformer | |
| Li et al. | Research on effects of transformer DC bias on negative sequence protection | |
| CN104459578B (en) | The remanent magnetism method of estimation of Yyn0 type three-phase group formula transformator non-faulting tripping operations | |
| Sekaran | Magnetic circuits and power transformers | |
| Chiesa et al. | Systematic switching study of transformer inrush current: simulations and measurements | |
| Gusev et al. | Evaluating the effect of geoinduced currents on the startup modes of power transformers | |
| Hawley et al. | Performance of a 1 mv a high temperature superconductors-enabled saturable magnetic core-type fault current limiter | |
| Lin et al. | Transient model and simulation in three-phase three-limb transformers |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |