CN107728000A - A kind of anti-error selection method of small current neutral grounding based on five tenses phase ground increment current - Google Patents
A kind of anti-error selection method of small current neutral grounding based on five tenses phase ground increment current Download PDFInfo
- Publication number
- CN107728000A CN107728000A CN201710405146.8A CN201710405146A CN107728000A CN 107728000 A CN107728000 A CN 107728000A CN 201710405146 A CN201710405146 A CN 201710405146A CN 107728000 A CN107728000 A CN 107728000A
- Authority
- CN
- China
- Prior art keywords
- phase
- current
- value
- increment
- ground
- 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
- 230000007935 neutral effect Effects 0.000 title claims abstract description 28
- 238000010187 selection method Methods 0.000 title claims abstract description 12
- 230000001052 transient effect Effects 0.000 claims abstract description 52
- 238000012544 monitoring process Methods 0.000 claims abstract description 40
- 230000004069 differentiation Effects 0.000 claims abstract description 10
- 230000001186 cumulative effect Effects 0.000 claims abstract description 9
- 238000001514 detection method Methods 0.000 claims abstract description 9
- 230000007257 malfunction Effects 0.000 claims abstract description 7
- 230000009977 dual effect Effects 0.000 claims abstract description 6
- 238000000034 method Methods 0.000 claims description 31
- 238000005070 sampling Methods 0.000 claims description 20
- 230000005611 electricity Effects 0.000 claims description 9
- 230000008676 import Effects 0.000 claims description 8
- 241001269238 Data Species 0.000 claims description 4
- 238000004458 analytical method Methods 0.000 claims description 3
- 238000004422 calculation algorithm Methods 0.000 claims description 2
- 238000012790 confirmation Methods 0.000 claims 1
- 238000009826 distribution Methods 0.000 description 29
- 238000007363 ring formation reaction Methods 0.000 description 18
- 230000007704 transition Effects 0.000 description 12
- 238000005516 engineering process Methods 0.000 description 8
- 230000001629 suppression Effects 0.000 description 8
- 238000004088 simulation Methods 0.000 description 5
- 230000006698 induction Effects 0.000 description 4
- 238000009413 insulation Methods 0.000 description 3
- 230000008569 process Effects 0.000 description 3
- 238000004364 calculation method Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000002347 injection Methods 0.000 description 2
- 239000007924 injection Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000000737 periodic effect Effects 0.000 description 2
- 240000002853 Nelumbo nucifera Species 0.000 description 1
- 235000006508 Nelumbo nucifera Nutrition 0.000 description 1
- 235000006510 Nelumbo pentapetala Nutrition 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 230000019771 cognition Effects 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000009795 derivation Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- IXSZQYVWNJNRAL-UHFFFAOYSA-N etoxazole Chemical compound CCOC1=CC(C(C)(C)C)=CC=C1C1N=C(C=2C(=CC=CC=2F)F)OC1 IXSZQYVWNJNRAL-UHFFFAOYSA-N 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 230000006870 function Effects 0.000 description 1
- 230000005283 ground state Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000005191 phase separation Methods 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 238000010615 ring circuit Methods 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/08—Locating faults in cables, transmission lines, or networks
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
- Emergency Protection Circuit Devices (AREA)
Abstract
The present invention based on five tenses mutually ground increment current the anti-error selection method of small current neutral grounding, including (1) calculate compare zero-sequence current Sudden Changing Rate more than setting value it is no or ground connection difference of phase currents be more than the ungrounded phase amount k1SNo again, whether the doubtful ground connection of qualitative discrimination or electric leakage occur；(2) measuring and calculating compares certain phase time transient state phase ground increment current and is more than corresponding setting value and more than other two-phase K1SIt is no again, decide whether cumulative suspected malfunctions number；(3) mutually incremental current value is respectively greater than other two-phases value K to the transient state phase after calculating relatively2SIt is no again, just sentence whether ground path Earth Phase, or discriminate whether intermittent electric leakage line electrical leakage phase by the secondary transient fault number in 3 seconds；(4) with calculating after failure half phase of the 8th week two non-faulting phases increment current phase difference or the three-phase electric current, as dual anti-error differentiation；(5) detection compares Earth Phase phase ground incremental current value of the failure after 5 seconds and is more than ungrounded phase value KHSNo again, whether monitoring failure continues.
Description
Technical field
The present invention relates to power distribution network small current earthing wire-selecting method, and more particularly to one kind, based on five tenses, mutually increment is electric
The anti-error selection method of small current neutral grounding of stream.
Background technology
Among existing distribution low current single-phase earthing typical case's monitoring technology method, it there are problems that as follows：
1st, traditional monitoring technology is the stable state zero sequence electricity after earth fault by same power source bus difference branched line
Flow valuve and power direction are compared, and zero-sequence current amplitude maximum and zero sequence power direction are pointed to the circuit of bus by circuit
It is judged to faulty line.This technology can be used in principle in the past without the distribution line for equipping arc suppression coil, but with
Equipped in net after arc suppression coil, rear stable status zero-sequence current amplitude of the same power source bus difference branched line in earth fault
It is close, zero sequence power direction is identical, this traditional monitoring technology is just difficult to differentiate between faulty line and non-fault line.
2nd, zero-sequence current Sudden Changing Rate comparison method solves multichannel radiation of the distribution in same bus of equipment arc suppression coil
Occur the route selection problem of single-phase earthing between road, but cyclization net adjacent lines ground connection or there is behaviour shown in Fig. 3 (a)
The property made disturbance vibration zero-sequence current and Fig. 4 (a) shown in induction disturbance vibration zero-sequence current when, there is to ungrounded line
The erroneous judgement wrong report problem on road.
3rd, the distribution singlephase earth fault Section Location based on difference of phase currents is to consider radial line without electricity
Signal source is pressed, utilizes monitoring point label method Judging fault area along three-phase current Sudden Changing Rate similarity factor comparison method+faulty line
Section.This method goes for the multiple-limb radial line under same bus in theory, but is wherein mutated only with to phase current
The method for measuring mathematics derivation distinguishes load variations and single-phase earthing, it is difficult to distinguishes that such as transformer excitation flow is non-with containing
The difference of periodic component single-phase-to-ground current；Set using according to live different situations and ask for three-phase current Sudden Changing Rate harmonic wave
Ratio and the method for similarity factor are unsuitable for voltage and become zero phase single-phase earthing, and application is also more complicated；And for going out
Induction disturbance vibration phase current shown in operability disturbance vibration difference of phase currents and Fig. 4 (b) shown in existing Fig. 3 (b) is dashed forward
During variable, the erroneous judgement wrong report problem to ungrounded circuit is equally existed.
4th, the smart grounding distribution system of mains neutral point low resistance combination bus three-phase metallic earthing Sofe Switch can be with
Resonance overvoltage caused by effective suppression continuation low-resistance single-phase earthing is possible, but the system uses traditional stage zero sequence
Current protection carries out earthing wire-selecting and is not suitable for senior middle school's resistance single-phase earthing, and the program must be by numerous distribution power transformers
Delta connection transform star-star connection as, its scheme implement it is with high costs.
5th, other Low frequency signal injection method low current single phase earth fault detection technologies for low-impedance earthed system Detection results also compared with
It is good, but it is not suitable for senior middle school's resistance single-phase earthing yet, and signal injection device is pressed in need to increasing, on the one hand there is to netting twine
The a certain degree of low-frequency current impact in road, on the other hand also brings newly-increased medium-voltage equipment safety management risk to distribution scene
With the trouble of engineering construction.
6th, wrong report is judged by accident easily in the fluctuation of load using the earthing detection technology of wavelet analysis；Travelling Wave Fault Location technology exists
It is preferable to detect the theoretical effect of uniline single-phase earthing, but is still not suitable for baroque power distribution network.
The problems of comprehensive analogous technical method for concluding existing grounding monitor, to be missed wherein important is erroneous judgement the most
Report probability high；According to researching and analysing, basic reason is that the tense signal of all these method of discrimination ground connection feature used is single,
It is difficult to check of genuineness single-phase earthing.
The content of the invention
Goal of the invention：For above-mentioned prior art, there is provided a kind of Modern power distribution net being applied to including cyclization circuit
Small current neutral grounding automatic route selection method, while effectively solving the problems, such as to be grounded automatic route selection, take into account and connect for true and false low current
The anti-error differentiation on ground, realize accuracy and reliability requirement for small current earthing wire-selecting.
Technical scheme：A kind of anti-error selection method of small current neutral grounding based on five tenses phase ground increment current, including it is as follows
Step：
(1) each monitoring point Current Transformer Secondary outlet is connected with the current sampling circuit of corresponding ground monitor；⑵
Measuring and calculating compare zero-sequence current Sudden Changing Rate more than setting value it is no or ground connection difference of phase currents be more than the ungrounded phase amount k1STimes
No, whether the doubtful ground connection of qualitative discrimination or electric leakage occur；(3) measuring and calculating compares certain phase time transient state phase ground increment current and is more than corresponding set
Definite value and more than other two-phase K1SIt is no again, decide whether cumulative suspected malfunctions number；(4) increase to the transient state phase phase after calculating relatively
Amount current value is respectively greater than other two-phases value K2SIt is no again, just sentence whether ground path Earth Phase, or by 3 seconds time temporarily
The state number of stoppages discriminates whether intermittent electric leakage line electrical leakage phase；Calculate failure after the 8th week two non-faulting phases half phase
Ground increment current phase difference or the three-phase electric current, as dual anti-error differentiation；(6) Earth Phase phase of the failure after 5 seconds is compared in detection
Ground incremental current value is more than ungrounded phase value KHSNo again, whether monitoring failure continues.
Further, (2) the step comprises the following steps：
(2.1) in real time measuring and calculating current time before the 2nd cycle the all-round current sample absolute value of three-phase accumulated value：When the value is more than zero, direct measuring zero-sequence current is dashed forward
Variable and three-phase current Sudden Changing Rate：i0k-i0k-2N=Δ i0k、iAk-iAk-2N=Δ iAk、iBk-iBk-2N=Δ iBk、iCk-iCk-2N=
ΔiCk；When the value is not more than zero, symmetrical components i is first obtained using vector analytic methodASk、iBSk、iCSk, then calculate three-phase current
Sudden Changing Rate and zero-sequence current Sudden Changing Rate：iAk-iASk=Δ iAk、iBk-iBSk=Δ iBk、iCk-iCSk=Δ iCk、ΔiAk+ΔiBk+Δ
iCk=Δ i0k；(2.2) first by zero-sequence current Sudden Changing Rate and the setting value i of the amount0SCompare, work as appearance | Δ i0k|>i0SWhen, just
It is qualitative to be judged to failure, remember this moment k=0, t=0 and start the cumulative of sampling number and time, and store k=-2N to k
=1 and later all sampled datas；Then go to the step (3)；When | Δ i0k|<Δi0SWhen, then respectively by three-phase electricity
Flow Sudden Changing Rate Δ iAk、ΔiBk、ΔiCkWith the setting value i of the amount1SCompare, when certain, mutually the value is more than the setting value and the phase
Jump-value of current is more than the k of other two-phase amounts1STimes when, just it is qualitative be judged to failure, remember this moment k=0, t=0 and open
Beginning sampling number and time it is cumulative, and store k=-2N to k=1 and later all sampled datas；Then go to the step
Suddenly (3)；
Wherein, N is the sampling number per power frequency period, and since k be the sampling sequence number breaking down, and t is from generation event
Hinder the timing started, iAk、iBk、iCkRespectively k-th of A, B, C phase current sampling value, IAQ、IBQ、ICQRespectively current time it
The accumulated value of the all-round current sample absolute value of preceding 2nd cycle A, B, C phase, i0kFor k-th of zero-sequence current sampled value, i0k-2NFor
The zero-sequence current sampled value of the first two power frequency period of k-th of sequence number, iAk-2N、iBk-2N、 iCk-2NBefore respectively k-th of sequence number
A, B, C phase current sampling value of two power frequency periods.
Further, (3) the step comprises the following steps：
(3.1) with calculating the phase in the three-phase time transient state period accumulated value of increment current absolute value (3.2) if IAG1Or IBG1Or ICG1More than setting value I1S, just compare three-phase
The accumulated value, when certain, mutually the value is more than other two-phases value K1STimes when, put L with regard to correspondingA=1 or LB=1 or LC=1, from T=0
Start gradually to add up；If not meeting accumulated value is more than setting value I1setOr certain mutually the value is not more than other two-phases value K1STimes
Condition, then program return；
Wherein, LA、LB、LCRespectively A, B, C phase is leaked electricity flag bit, and T is electric leakage accumulative frequency.
Further, (4) the step comprises the following steps：
(4.1) with transient state three-phase current sampling phase ground increment current after the measuring and calculating of fault component algorithm；(4.2) increment is calculated
The accumulated value of absolute value(4.3) comparing three-phase should
Accumulated value, when certain, mutually the value is respectively greater than the K of the another two-phase value2STimes when, just by the fault flag set of this, primary election should
It is mutually faulty line failure phase；When certain mutually the value be respectively greater than the another two-phase value K2STimes when, if meeting t=3 seconds and T >=3
Condition, then sentence corresponding to LA=1 or LB=1 or LC=1 separate faulty line failure phase for the intermittent electric leakage of generation, if
The condition of t=3 seconds and T >=3 is not met, then program returns.
Further, (5) the step comprises the following steps：
(5.1) when being judged to earth fault, calculating and by half phase of the non-faulting phase of the 8th power frequency period after failure increment
Electric current and corresponding setting value I8SCompare；(5.2) when the increment is more than the setting value, with calculating the phase of two non-faulting phases
Increment current initial phase and both phase difference θ8, program import phase difference compare section；Otherwise import the increment three compare
Compared with section；(5.3) when program, which imports phase difference, to be compared section, by Δ θ8With set angle angle value θ8SCompare, when | Δ θ8| less than θ8S
When, it is confirmed that selected phase is faulty line failure phase；When | Δ θ8| not less than θ8SWhen, then confirm as ungrounded or non-electric leakage event
Barrier, program return；(5.4) when program, which imports the three of the increment, to compare section, the failure phase of the 8th week after failure is calculated respectively
With half phase of non-faulting phase increment current and by both compared with；When failure, mutually the electric current is more than the non-faulting electric current
K8SWhen, it is confirmed that being ground connection or leak current fault；Otherwise program returns.
Further, (6) the step comprises the following steps：
Consequent malfunction status monitoring is carried out by the ground monitor for respectively sending Trouble Report：(6.1) failure calculates three after 5 seconds
Phase current sampling accumulated valueWherein subscript j is that failure starts to tire out after 5 seconds
The sampling number added；(6.2) with calculating phase of the failure after 5 seconds incremental current value IAH-IAQ=IAGH、IBH-IBQ=IBGH、 ICH-ICQ
=ICGH；(6.3) three-phase mutually incremental current value is compared, when detecting that mutually the value is respectively greater than the K of the another two-phase value to failureHSTimes
When, just report ground connection or leak current fault continue；Otherwise it is big to treat that continuous detection all occurs without Earth Phase phase ground incremental current value for 3 seconds
In other two-phase value KHSTimes situation when, just report ground connection or leak current fault disappear.
Further, the phase increment current calculated value be increment of sample absolute value accumulated value, including counted
Calculate as half cycle average, all-round average, amplitude or virtual value.
Beneficial effect：It is of the invention compared with existing small current neutral grounding monitoring method, there is following basic effect：
One, so that in the relatively large secondary transient state of signal intensity and rear transient state, mutually increment current is used as Basic Criteria signal
Source so that the present invention is suitable for the not same district that voltage electrical connects same of the various structure distributions including cyclization circuit
Between all voltage-phases under the high, medium and low resistance single-phase earthing that is occurred；
Secondly, criterion information comprehensive and abundant used, and mutually increment current is typically big because of ground path Earth Phase time transient state
In zero sequence increment current so that the single-phase earthing Standard resistance range that the present invention is suitable for accordingly improves；
Thirdly, the present invention be applicable not only to the single-phase earthing of continuity and noncontinuity power frequency ripple, can also be applied to shape
The single-phase earthing of the non-all-round power frequency ripple of periodicity or aperiodicity as shown in Figure 5 so that by environment, weather and be heated old
The reason such as changing causes electric leakage caused by insulation damages and ground connection being capable of early detection.In Fig. 5, reaping hook ripple is non-all-round power frequency
Ripple, in insulation damages aperiodicity sickle shaped interrupted wae is presented initial stage in it, is developing progressively afterwards as periodicity sickle shaped interval
Ripple, periodicity reaping hook ripple are alternate with full power frequency ripple, and being further continued for development just turns into the full power frequency continuous wave of complete period property.
Four, the present invention has the multiple anti-error discrimination function for true and doubtful small current neutral grounding concurrently so that low current
The reliability and accuracy of earthing wire-selecting have the raising of essence.
Brief description of the drawings
Fig. 1 is the implementation procedure block diagram of the present invention, in figure：Δi0、Δi0SFor zero-sequence current Sudden Changing Rate and its cross limit value；
ΔiA1、ΔiB1、ΔiC1And i1SRespectively phase earth-current Sudden Changing Rate and its excessively limit setting value；IAG1、IBG1、ICG1、I1SRespectively
Secondary transient state three-phase phase ground increment current and its excessively limit setting value；IAG2、IBG2、ICG2Transient state three-phase phase ground increment current after respectively
Value；IAG8、IBG8、ICG8、I8SRespectively after failure the phase of non-faulting phase half of the 8th power frequency period increment current and its cross limit set
Definite value；Δθ8、θ8SWith respectively corresponding to half phase of two ungrounded phases phase difference of increment current and its corresponding setting value；
k1S、K1S、K2S、K8S、KHSRespectively failure is mutually relative to non-faulting mutually in transient state, secondary transient state, rear transient state, transition state, rear stable state
Phase ground increment current multiplying power setting value.
Fig. 2 is time for simplifying distribution network model and its being grounded when the G points of cyclization circuit are in C phase voltage amplitude phases
Transient state three-phase phase ground increment current and zero sequence increment current amplitude and polarity distribution figure；In fig. 2, power transformer 10kV sides
For widely used delta connection in actual distribution, P00 is that the side is switched and its monitoring point is numbered；R11, R21 are respectively ring
Net outlet switch and its monitoring point numbering；R12 and disengaging wiretap and its monitoring point that R13, R14 and R15 are respectively ring main unit
Numbering；B31, B32 are respectively the outlet switch and branch switch and its monitoring point numbering of radial line；EPLG is except in figure
All equivalent parallel line mutual-ground capacitor sums beyond marked cyclization circuit and radial line；XHQ becomes to be connected to Z wiring ground connection
Arc suppression coil under depressor, the overcompensation degree of arc suppression coil is 10%.
Fig. 3 (a), Fig. 3 (b) are respectively that Fig. 2 simplifies distribution network model in divided ring circuit power transmission due to the non-concurrent conjunction of three-phase
The zero sequence increment current and three-phase mutually increment current emulation that operability disturbance vibration caused by lock is monitored in B31 points
Waveform.
Fig. 4 (a), Fig. 4 (b) are respectively that Fig. 2 simplifies distribution network model and released thunder and lightning lotus because arrester occurs in radial line
Caused by the induction property disturbance zero sequence increment current that is monitored in P00 points of vibration and three-phase mutually increment current emulation ripple
Shape.
Fig. 5 with simplifying the phase of 10kV distribution network models for Fig. 2 large, medium and small type power distribution networks of the electric capacity within 150 μ F occurs
The zero sequence increment current of insulation damages starting stage single-phase earthing and the phase of Earth Phase ground increment current simulation waveform.
Fig. 6 is to simplify 10kV distribution network models 10k Ω transition occurs when the G points of cyclization circuit C phases are in voltage magnitude phase
Five tense three-phase phases of the resistance single-phase earthing in power supply and Ge Lu bus outlet switch P00, R11, R12, R21, R31 monitoring points
Ground increment current simulation waveform.
Fig. 7 is that 10k Ω occur when the G points of cyclization circuit C phases are in voltage null value phase for Fig. 2 simplification 10kV distribution network models
The three-phase phase ground increment current simulation waveform of R11, R12 point of transition resistance single-phase earthing.
The R of divided oscillator most serious when Fig. 8 is cyclization circuit A phases G point 10k Ω transition resistance small current neutral groundings12Monitoring point
Three-phase phase ground increment current oscillogram in 3 seconds.
Embodiment
Further explanation is done to the present invention below in conjunction with the accompanying drawings.
1. build the small current neutral grounding monitoring system of the present invention：
As shown in Fig. 2 each power switch, outlet switch, loop grid respectively switch in distribution, radial line respectively switchs
Etc. the supporting ground monitor of monitoring point installation present invention institute, by the threephase current transformer of each way switch, zero sequence current mutual inductance
Device is connected with the ground monitor at this respectively；The ground monitor of each monitoring point with this share communicator be connected,
Each communicator is connected with center to center communications device, center to center communications device is connected with center monitor, forms distribution shown in Fig. 2
Small current neutral grounding monitoring system.
2. set five tense correlation definite values involved by the failure line selection of ground monitor：
According to high, medium and low resistance small current neutral grounding or the leak current fault of covering and take into account determining for cyclization circuit minimum split ratio
It is worth setting principle, five tense correlation definite values of the small current neutral grounding in Fig. 2 distribution network models or leak current fault route selection is set
For： i0S=0.1A, i1S=0.15A, k1S=1.5, I1S=5A, K1S=1.5, K2S=1.3, I8S=4A, θ8S=60 °, K8S=
1.2、 KHS=1.2.
3. the course of work of the present invention when 10k Ω transition resistances ground connection occurs for the C phases G of cyclization circuit shown in Fig. 2 points：
When C phase 10k Ω transition resistance single-phase earthings occur for G points, the three-phase time transient state at online each monitoring point mutually increases
The magnitude relationship and direction of amount electric current and zero sequence increment current are as shown in the arrow in Fig. 2 at each corresponding monitoring point；Wherein power supply
The phase of monitoring point, P00, R11, R12, R21 monitoring point of cyclization circuit and radial line outlet B31 monitoring points in five tenses
Increment current simulation waveform is as shown in Figure 6.The monitor course of work of each monitoring point is：
The phase for the ungrounded phase of full distribution that G points are collected increment current from grounding resistance flow into C phase lines after, from two
Individual direction flows to bus respectively：Bus and power supply are flowed to by R11 monitoring points all the way, another way passes through R12, R13, R14, R15
Bus and power supply are flowed to monitoring points such as R21, two loops time transient state phase earth-current is within looped network with grounding resistance and cyclization line
The contact point of road C phase conductors is boundary, and flow direction is opposite.
R11 monitoring points to bus path is short, line impedance is small, flow to the failure of reference power source side mutually increment current
It is relatively large, therefore 1. transient state qualitative discrimination：The monitor Earth Phase monitor it is current before the 2nd periodic current be more than 0,
The absolute value of transient state zero-sequence current Sudden Changing Rate | Δ i0|>i0S=0.1A setting value or Earth Phase transient state phase ground increment current
Absolute value | Δ iC1|>i1S=0.15A mistake limit setting value, and meet | Δ iC1|>k1S|ΔiA1|=1.5 | Δ iA1|、|ΔiC1
|>k1S|ΔiB1|=1.5 | Δ iB1|, this feature meets transient state earth fault criterion, therefore qualitative be judged to be grounded or leak electricity
Failure occurs, k=k+1 failure sampling number is accumulative since k=0 and t=k/fcFailure timing, program imports quantitative
Differentiate；2. the quantitative anti-error differentiation of secondary transient state：Monitor detect failure phase time transient state mutually increment current half cycle absolute value it
With for ICG1=14.25A, more than I1S=5A corresponding setting value；The ungrounded phase value sum is IAG1=IBG1=1.527A, symbol
Close ICG1(=14.25A)>K1SIAG2(=1.5 × 1.527=2.29A), ICG1(=14.25A)>K1SIBG2(=1.5 × 1.527
=2.29A) secondary transient state earth fault criterion；3. the quantitative anti-error differentiation of rear transient state：The three-phase phase earth-current value of transient state afterwards
All increase in the case where arc suppression coil resonant tank gradually works, wherein the phase of failure phase ground increment current half cycle
Absolute value sum is ICG2=9.39A, the value sum of non-faulting phase is IAG2=2.17A, meets ICG2(=9.39A)>K2SIAG2
(=1.3 × 2.17=3.255A), ICG2(=9.39A)>K2SIBG2The rear transient state ground connection of (=1.3 × 2.17=3.255A) is sentenced
According to condition, the possibility that the induction disturbance of the close feature of rear transient state three-phase phase ground incremental current value is vibrated is eliminated；Accordingly,
It is ground path Earth Phase that R110 points monitor, which just sentences cyclization circuit C phases,；4. the dual anti-error differentiation of transition state：R11 takes failure again
Afterwards the first half phase of the 8th power frequency period increment current carry out dual anti-error differentiation：With calculating half phase of ungrounded phase A phases
Increment current absolute value sum is IAG8=9.537A, the value sum are more than corresponding setting value I8S=4A, illustrate not influence non-connect
The accuracy of ground phase ground increment current phase calculation；With calculating the phase of two ungrounded phases again increment current phase difference θAG8-
θBG8=Δ θ8, the phase difference calculating value is about 0 °, is met | Δ θ8|<θ8SThe faulty line non-faulting of (=60 °) is mutually in transition
The ground connection phase difference criterion at state end, eliminate the non-concurrent combined floodgate disturbance of 120 ° of three-phase phase ground increment current phase mutual deviation
The possibility of vibration, then it is faulty line failure phase to confirm this circuit C phases.
R12, R13, R14, R15 and R21 etc. put monitored part of path tandem paths length, although its phase ground increment current
The impedance in loop is relatively large, flowing to the C phases of power supply, mutually increment current is relatively weak, but these monitoring points can also repeat R11
The anti-error route selection of whole differentiate process, it is ground path Earth Phase to confirm this circuit C phases.
The anti-error route selection of whole that power supply P00 monitoring points also repeat R11 differentiates process, confirms in its following circuit C phase to be to connect
Ground phase.
The presence when G points are grounded of radial line B31 monitoring points may cross the secondary transient zero-sequence or phase earth-current Sudden Changing Rate of limit,
Qualitative discrimination of ground monitor may start at this, but because mutually incremental current value is identical for transient state three-phase thereafter, therefore quantitatively sentence
Do not pass through.
After earth fault 5 seconds, each ground monitor for sending Trouble Report with detecting the phase of Earth Phase increment current
All-round absolute value accumulated value is 71.26A, the value of ungrounded phase is 40.72A, meets ICGH(71.26A)>KHSIAGH(=1.2
× 40.72=48.86A), ICGH(71.26A)>KHSIBGHThe ground connection protensive features criterion bar of (=1.2 × 40.72=48.86A)
Part, therefore confirm that ground state continues.
By the ground monitor minute for P00, R11, R12, R13, R14, R15, R21 point for detecting faulty line failure phase
By this point failure information and Earth Phase time transient state, mutually incremental current value is not reported to Surveillance center.
4. Surveillance center's artificial cognition fault section
The ground monitor earth fault letter of P00, R11, R12, R13, R14, R15, R21 point is received in Surveillance center
After breath and the ground incremental current value report of Earth Phase time transient state phase, by the center operator Judging fault section, differentiate
Method is as follows：
1. because power supply monitoring point and cyclization circuit send ground connection or electric leakage report, therefore it is faulty line to sentence the cyclization circuit,
Then the further Judging fault section between the cyclization circuit respectively sends the monitoring point of report.
2. the failure phase time transient state phase ground increment current difference between comprehensive more each two adjacent monitoring point, because of R11 and R12
The difference between two monitoring points is maximum, therefore will be judged to fault section between R11 and the adjacent monitoring points of R12 two.(referring to Fig. 6)
It is fixed because starting if single-phase earthing or leak current fault occurs in distribution other positions such as bus and radial line
The startup number of the failure occurs less than cyclization circuit for the ground monitor number that amount differentiates, the description of its course of work is no longer superfluous
State.
The composite can be widely applied to Modern power distribution net of the power system including more power supply cyclization circuits and other
The low current single-phase earthing of every profession and trade enterprises and institutions power distribution network or the anti-error route selection of electric leakage.
The inventive method is in forming process, to the various structures distribution including Fig. 2 institutes representation model in different circuits
Diverse location section, different voltage-phases and different resistances transition resistance under small current neutral grounding carried out respectively repeatedly
Emulation and simulation, in record small current neutral grounding mutually increment current and zero sequence increment current waveform and doubtful small current neutral grounding
Disturbance vibration is used videotape to record on the basis of ground and zero-sequence current waveform, has been summarized and has been worked as in the distribution for being configured with arc suppression coil in parallel
In faulty line when small current neutral grounding occurs and non-fault line three-phase mutually the pass of increment current and zero sequence increment current
It is feature, three-phase mutually the relationship characteristic of increment current and zero sequence increment current, and will of doubtful small current neutral grounding disturbance vibration
It is collected among table 1；These current relationship features just turn into the regular foundation of the inventive method.
In the subscript of each tense current phasor listed by table 1：FG represents faulty line failure phase and suspected malfunctions circuit
Suspected malfunctions relatively, SG represent the non-faulting of faulty line relatively, F0 represent that faulty line zero-sequence component, S0 represent non-
Stable state after faulty line zero-sequence component, AG, BG, CG represent the three of non-fault line relatively component, H represented respectively；Transient state is dashed forward
First Sudden Changing Rate, other tense current phasor subscripts 1,2,8 after the expression earth fault of variable subscript 1 represent failure respectively
Afterwards the 1st, 2, the half cycle vector in 8 cycles；k1、K1、K2、K8、KHFor faulty line failure phase and non-faulting mutually respectively transient state,
Secondary transient state, rear transient state, the increment current multiplying power of transition state and rear stable state；It is respectively k that it, which surveys scope,1>=2~3；K1>=2~3；
K2>=1.6~2；K8>=1.4~2；KH=1.4~2.
The five tenses phase ground increment current relationship characteristic comparison sheet of the small current neutral grounding of table 1 and disturbance vibration
Related definition and conceptual illustration involved by the inventive method：
1st, the mutually definition of ground increment current
In small current neutral grounding system, increase respectively in three-phase line because single-phase earthing or doubtful single-phase earthing occurs
The magnitude of current added；Because the increment current is using three-phase conducting wire and its impedance between the earth as loop, therefore increase with being referred to as phase
Measure electric current.
2nd, the definition of five tenses phase ground increment current
Transient state phase ground increment current --- occur in first current sample after single-phase earthing or doubtful single-phase earthing
Reflect the increment current of relatively characteristic relation, this method includes zero-sequence current Sudden Changing Rate and difference of phase currents, and symbol is
Δi01、ΔiA1、ΔiB1、ΔiC1。
Secondary transient state phase ground increment current --- after generation single-phase earthing or doubtful single-phase earthing in half of power frequency period
Mutually increment current；Symbol isIts calculating value in the method is designated as IAG1、IBG1、ICG1。
Transient state phase ground increment current --- the phase after generation single-phase earthing or doubtful single-phase earthing in the 1st power frequency period
Ground increment current；Symbol isIt is in the method as definition time transient state and rear transient state phase ground increment current
Tense with reference to amount (not actually used in this method program).
Transient state mutually increment current afterwards --- occur after single-phase earthing or doubtful single-phase earthing in the 2nd power frequency period
Mutually increment current；Symbol isIts calculating value in the method is designated as IAG2、IBG2、ICG2。
Equilibrium transport ground increment current afterwards --- the work for entering stable state after single-phase earthing or doubtful single-phase earthing occurs
Frequency phase ground increment current；Symbol isIts calculating value in the method is designated as IAGH、IBGH、ICGH。
Transition state phase ground increment current --- the power frequency phase ground increment current at the beginning of from secondary transient state end to rear stable state.
It is used as primary route selection in this method with the 2nd power frequency period after the failure of anti-misrecognition and as dual anti-error differentiation
After failure the phase of the 8th power frequency period increment current it is middle and high resistance ground connection when belong to transition state electric current, belong in low-impedance earthed system
In rear steady-state current；The current symbol of the preceding half cycle of wherein the 8th week isIts amount of calculation in the method
Value is designated as IAG8、IBG8、ICG8。
Mutually increment current is using continuity power frequency sine wave as the current waveform sample after the single-phase earthing of keynote to five tenses
This given a definition that, although and periodically the single-phase earthing of non-all-round phase earth-current power frequency ripple is in only a kind of width of five tenses
Value and the relatively uniform phase earth-current waveform of shape, but this method is not influenceed to its effective differentiation.
3rd, the acquisition modes of five tenses phase ground increment current
All three-phases or biphase current and directly subtracted each other by fault component method before and after failure needed for can directly detecting
The phase arrived increment current be referred to as holographic mutually increment current, referred to as mutually ground increment current in the present invention；It is only capable of directly detecting
During after to failure and electric current before miss fault, mutually increment current needs to use the current phasor after failure to pass through parsing
Computing can just obtain, therefore with being called solution phase separation increment current；The latter refers to but does not declare model in this patent in the present invention
Within enclosing.
4th, the zero-sequence current of non-fault line and faulty line --- during low current single-phase earthing, the failure of non-fault line
It is mutually essentially identical with each tense phase ground incremental current value of non-faulting phase and direction, therefore secondly transient zero-sequence current symbol is
3I″0；The failure of faulty line has mutually converged the ungrounded phase phase ground increment current of the whole network in secondary transient state at grounding resistance, and
This converges electric current, and with the phase of the ungrounded phase of faulty line increment current is in opposite direction, so, the secondary transient zero-sequence of faulty line
Electric current belongs to the vector sum of Earth Phase and the three-phase non-equivalence phase ground increment current of ungrounded phase, and symbol is expressed as。
5th, the definition of high, medium and low resistance --- this method is designing according to grounding resistance and the proportionate relationship of line voltage
Precision defines high resistant, middle resistance, low-resistance and metallic earthing in the range of can monitoring, 1 Ω/V~0.1 Ω/V is defined in it
High resistance ground, 0.1 Ω/V~0.01 Ω/V are middle resistance is grounded, 0.01~0.001 Ω/V is low-impedance earthed system, 0.001 Ω of ＜/V is
Metallic earthing.
Described above is only the preferred embodiment of the present invention, it is noted that for the ordinary skill people of the art
For member, under the premise without departing from the principles of the invention, some improvements and modifications can also be made, these improvements and modifications
It should be regarded as protection scope of the present invention.
Claims (7)
1. a kind of anti-error selection method of small current neutral grounding based on five tenses phase ground increment current, it is characterised in that including as follows
Step：
(1) each monitoring point Current Transformer Secondary outlet is connected with the current sampling circuit of corresponding ground monitor；(2) calculate
Compare zero-sequence current Sudden Changing Rate more than setting value it is no or ground connection difference of phase currents be more than the ungrounded phase amount k1SIt is no again, it is fixed
Property differentiate it is doubtful ground connection or electric leakage whether occur；Measuring and calculating compare certain phase time transient state mutually increment current be more than corresponding setting value and
More than other two-phase K1SIt is no again, decide whether cumulative suspected malfunctions number；(4) transient state phase phase ground increment current after calculating relatively
Value is respectively greater than other two-phases value K2SIt is no again, just sentence whether ground path Earth Phase, or by the secondary transient fault time in 3 seconds
Number discriminates whether intermittent electric leakage line electrical leakage phase；(5) increment is electric with calculating after failure half phase of the 8th week two non-faulting phases
Phase difference or the three-phase electric current are flowed, as dual anti-error differentiation；(6) Earth Phase of the failure after 5 seconds mutually increment current is compared in detection
Value is more than ungrounded phase value KHSNo again, whether monitoring failure continues.
2. the small current neutral grounding anti-error selection method according to claim 1 based on five tenses phase ground increment current, it is special
Sign is (2) the step comprises the following steps：
(2.1) in real time measuring and calculating current time before the 2nd cycle the all-round current sample absolute value of three-phase accumulated value：When the value is more than zero, direct measuring zero-sequence current is dashed forward
Variable and three-phase current Sudden Changing Rate：i0k-i0k-2N=Δ i0k、iAk-iAk-2N=Δ iAk、iBk-iBk-2N=Δ iBk、iCk-iCk-2N=
ΔiCk；When the value is not more than zero, symmetrical components i is first obtained using vector analytic methodASk、iBSk、iCSk, then calculate three-phase current
Sudden Changing Rate and zero-sequence current Sudden Changing Rate：iAk-iASk=Δ iAk、iBk-iBSk=Δ iBk、iCk-iCSk=Δ iCk、ΔiAk+ΔiBk+Δ
iCk=Δ i0k；(2.2) first by zero-sequence current Sudden Changing Rate and the setting value i of the amount0SCompare, work as appearance | Δ i0k|>i0SWhen, just
It is qualitative to be judged to failure, remember this moment k=0, t=0 and start the cumulative of sampling number and time, and store k=-2N to k
=1 and later all sampled datas；Then go to the step (3)；When | Δ i0k|<Δi0SWhen, then respectively by three-phase electricity
Flow Sudden Changing Rate Δ iAk、ΔiBk、ΔiCkWith the setting value i of the amount1SCompare, when certain, mutually the value is more than the setting value and the phase
Jump-value of current is more than the k of other two-phase amounts1STimes when, just it is qualitative be judged to failure, remember this moment k=0, t=0 and start
Sampling number and time it is cumulative, and store k=-2N to k=1 and later all sampled datas；Then go to the step
⑶；
Wherein, N is the sampling number per power frequency period, and since k be sampling sequence number breaking down, and t is from breaking down out
The timing of beginning, iAk、iBk、iCkRespectively k-th of A, B, C phase current sampling value, IAQ、IBQ、ICQRespectively the 2nd before current time
The accumulated value of the all-round current sample absolute value of cycle A, B, C phase, i0kFor k-th of zero-sequence current sampled value, i0k-2NFor k-th
The zero-sequence current sampled value of the first two power frequency period of sequence number, iAk-2N、iBk-2N、iCk-2NThe first two work of respectively k-th sequence number
A, B, C phase current sampling value in frequency cycle.
3. the small current neutral grounding anti-error selection method according to claim 1 based on five tenses phase ground increment current, it is special
Sign is (3) the step comprises the following steps：
(3.1) with calculating the phase in the three-phase time transient state period accumulated value of increment current absolute value (3.2) if IAG1Or IBG1Or ICG1More than setting value I1S, just compare three-phase
The accumulated value, when certain, mutually the value is more than other two-phases value K1STimes when, put L with regard to correspondingA=1 or LB=1 or LC=1, opened from T=0
Beginning gradually adds up；If not meeting accumulated value is more than setting value I1setOr certain mutually the value is not more than other two-phases value K1SBar again
Part, then program return；
Wherein, LA、LB、LCRespectively A, B, C phase is leaked electricity flag bit, and T is electric leakage accumulative frequency.
4. the small current neutral grounding anti-error selection method according to claim 1 based on five tenses phase ground increment current, it is special
Sign is (4) the step comprises the following steps：
(4.1) with transient state three-phase current sampling phase ground increment current after the measuring and calculating of fault component algorithm；(4.2) it is absolute to calculate the increment
The accumulated value of value(4.3) comparing three-phase, this is cumulative
Value, when certain, mutually the value is respectively greater than the K of the another two-phase value2STimes when, just by the fault flag set of this, primary election this mutually for therefore
Hinder line fault phase；When certain mutually the value be respectively greater than the another two-phase value K2STimes when, if meeting the condition of t=3 seconds and T >=3,
Then sentence corresponding to LA=1 or LB=1 or LC=1 separate faulty line failure phase for the intermittent electric leakage of generation, if not meeting t
=3 seconds and the condition of T >=3, then program return.
5. the small current neutral grounding anti-error selection method according to claim 1 based on five tenses phase ground increment current, it is special
Sign is (5) the step comprises the following steps：
(5.1) when being judged to earth fault, calculating and by half phase of the non-faulting phase of the 8th power frequency period after failure increment current
With corresponding setting value I8SCompare；(5.2) when the increment is more than the setting value, calculate two non-faulting phases phase increment electricity
Flow initial phase and both phase difference θ8, program import phase difference compare section；Otherwise the three of the increment is imported to compare section；
(5.3) when program, which imports phase difference, to be compared section, by Δ θ8With set angle angle value θ8SCompare, when | Δ θ8| less than θ8SWhen, just
Confirmation selected phase is faulty line failure phase；When | Δ θ8| not less than θ8SWhen, then confirm as ungrounded or non-leak current fault, program
Return；(5.4) when program, which imports the three of the increment, to compare section, the failure phase and non-faulting of the 8th week after failure are calculated respectively
Increment current and both are compared to half phase of phase；When failure, mutually the electric current is more than non-faulting mutually electric current K8STimes when,
It is confirmed that it is ground connection or leak current fault；Otherwise program returns.
6. the small current neutral grounding anti-error selection method according to claim 1 based on five tenses phase ground increment current, it is special
Sign is (6) the step comprises the following steps：
Consequent malfunction status monitoring is carried out by the ground monitor for respectively sending Trouble Report：(6.1) failure calculates three-phase electricity after 5 seconds
Stream sampling accumulated valueWherein subscript j is that failure starts cumulative adopt after 5 seconds
Sample number；(6.2) with calculating phase of the failure after 5 seconds incremental current value IAH-IAQ=IAGH、IBH-IBQ=IBGH、ICH-ICQ=ICGH；
(6.3) three-phase mutually incremental current value is compared, when detecting that mutually the value is respectively greater than the K of the another two-phase value to failureHSTimes when, just report
Accuse ground connection or leak current fault continues；Otherwise treat that continuous detection all occurs without Earth Phase phase ground incremental current value for 3 seconds and is more than other two
Mutually value KHSTimes situation when, just report ground connection or leak current fault disappear.
7. the small current neutral grounding anti-error route selection side according to any one of claims 1 to 6 based on five tenses phase ground increment current
Method, it is characterised in that the phase increment current calculated value be increment of sample absolute value accumulated value, including be calculated as
Half cycle average, all-round average, amplitude or virtual value.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710405146.8A CN107728000B (en) | 2017-05-31 | 2017-05-31 | Small-current grounding anti-error line selection method based on five-time phase-to-ground incremental current |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710405146.8A CN107728000B (en) | 2017-05-31 | 2017-05-31 | Small-current grounding anti-error line selection method based on five-time phase-to-ground incremental current |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107728000A true CN107728000A (en) | 2018-02-23 |
| CN107728000B CN107728000B (en) | 2021-05-18 |
Family
ID=61201281
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710405146.8A Active CN107728000B (en) | 2017-05-31 | 2017-05-31 | Small-current grounding anti-error line selection method based on five-time phase-to-ground incremental current |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107728000B (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109884466A (en) * | 2019-03-04 | 2019-06-14 | 中国矿业大学 | A kind of distribution earthing wire-selecting method recognizing double negative-sequence current vector correlation features |
| CN112462201A (en) * | 2020-12-16 | 2021-03-09 | 国网江苏省电力有限公司沛县供电分公司 | Annular power distribution network single-phase earth fault line selection method based on classification and identification |
| CN113552441A (en) * | 2020-04-24 | 2021-10-26 | 南京南瑞继保电气有限公司 | Single-phase earth fault detection method and device |
| CN115792504A (en) * | 2023-01-31 | 2023-03-14 | 国网山西省电力公司电力科学研究院 | Phase current abrupt change based power distribution network single-phase earth fault positioning method and system |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20120069638A1 (en) * | 2010-09-21 | 2012-03-22 | Renesas Electronics Corporation | Semiconductor device |
| CN103809070A (en) * | 2012-11-15 | 2014-05-21 | 施耐德电器工业公司 | Method and device for direction grounding fault detection on basis of three-phase current changes |
| CN103852693A (en) * | 2014-03-26 | 2014-06-11 | 马善娟 | Judging method of small current grounding line selection system |
| CN104614642A (en) * | 2015-01-27 | 2015-05-13 | 国家电网公司 | Small current grounding line selection method |
| CN104808114A (en) * | 2015-05-04 | 2015-07-29 | 中国矿业大学 | Low-current grounding fault line selection method based on wide-area zero-sequence voltage distribution characteristics |
| US20150364194A1 (en) * | 2014-01-17 | 2015-12-17 | International Business Machines Corporation | Writing multiple levels in a phase change memory |
| CN107179481A (en) * | 2017-07-06 | 2017-09-19 | 中国矿业大学 | The fault line selection method for single-phase-to-ground fault of annular isolated neutral power distribution network |
-
2017
- 2017-05-31 CN CN201710405146.8A patent/CN107728000B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20120069638A1 (en) * | 2010-09-21 | 2012-03-22 | Renesas Electronics Corporation | Semiconductor device |
| CN103809070A (en) * | 2012-11-15 | 2014-05-21 | 施耐德电器工业公司 | Method and device for direction grounding fault detection on basis of three-phase current changes |
| EP2733498A2 (en) * | 2012-11-15 | 2014-05-21 | Schneider Electric Industries SAS | Method and device for detecting directional grounding fault based on three phase current variation |
| US20150364194A1 (en) * | 2014-01-17 | 2015-12-17 | International Business Machines Corporation | Writing multiple levels in a phase change memory |
| CN103852693A (en) * | 2014-03-26 | 2014-06-11 | 马善娟 | Judging method of small current grounding line selection system |
| CN104614642A (en) * | 2015-01-27 | 2015-05-13 | 国家电网公司 | Small current grounding line selection method |
| CN104808114A (en) * | 2015-05-04 | 2015-07-29 | 中国矿业大学 | Low-current grounding fault line selection method based on wide-area zero-sequence voltage distribution characteristics |
| CN107179481A (en) * | 2017-07-06 | 2017-09-19 | 中国矿业大学 | The fault line selection method for single-phase-to-ground fault of annular isolated neutral power distribution network |
Non-Patent Citations (3)
| Title |
|---|
| HONGCHUN SHU.ET AL: "A fault line selection algorithm using neural network based on S-transform energy", 《2010 SIXTH INTERNATIONAL CONFERENCE ON NATURAL COMPUTATION》 * |
| 宗伟林 等: "矿井配电网单相接地故障选线与定位新方法", 《工矿自动化》 * |
| 王玮 等: "偏磁式消弧线圈自动跟踪补偿装置及配套选线装置在电网中的应用", 《冶金电流》 * |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109884466A (en) * | 2019-03-04 | 2019-06-14 | 中国矿业大学 | A kind of distribution earthing wire-selecting method recognizing double negative-sequence current vector correlation features |
| CN109884466B (en) * | 2019-03-04 | 2020-06-26 | 中国矿业大学 | Distribution network grounding line selection method for identifying double negative sequence current vector relation characteristics |
| CN113552441A (en) * | 2020-04-24 | 2021-10-26 | 南京南瑞继保电气有限公司 | Single-phase earth fault detection method and device |
| CN113552441B (en) * | 2020-04-24 | 2024-04-30 | 南京南瑞继保电气有限公司 | Single-phase earth fault detection method and device |
| CN112462201A (en) * | 2020-12-16 | 2021-03-09 | 国网江苏省电力有限公司沛县供电分公司 | Annular power distribution network single-phase earth fault line selection method based on classification and identification |
| CN115792504A (en) * | 2023-01-31 | 2023-03-14 | 国网山西省电力公司电力科学研究院 | Phase current abrupt change based power distribution network single-phase earth fault positioning method and system |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107728000B (en) | 2021-05-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106872852B (en) | Power distribution network single-phase disconnection based on residual voltage is grounded multiple fault type diagnostic method | |
| Kong et al. | A Novel Traveling-Wave-Based Main Protection Scheme for $\pm $800 kV UHVDC Bipolar Transmission Lines | |
| CN107728000A (en) | A kind of anti-error selection method of small current neutral grounding based on five tenses phase ground increment current | |
| CN100348990C (en) | Adaptive approach for route selection of grounded system connected to arc suppression coil | |
| CN111208387B (en) | Distribution network single-phase grounding line selection method based on synchronous phase current fault component comparison | |
| CN101291054B (en) | Diagnosis and protection method for residue current of ground fault in electrical power system | |
| CN103632029B (en) | Method for selecting neutral point grounding mode of medium voltage distribution network | |
| CN106324432A (en) | Single-phase grounding line selection method for small-current grounding system | |
| CN106353640A (en) | Fault location method, device and system for distribution lines | |
| CN108054764A (en) | A kind of multifunctional ligand power grid flexible ground device and control method | |
| Tan et al. | Sequential tripping strategy for a transmission network back-up protection expert system | |
| CN201234124Y (en) | Single-phase grounding failure wire selection automatic processing equipment for low current grounding system | |
| CN106646130B (en) | A kind of active distribution network Fault Locating Method compared based on current polarity and system | |
| CN110118913A (en) | A kind of arc suppression coil dispersion compensation distribution net work earthing fault selection method | |
| CN112255499A (en) | Phase current amplitude based power distribution network disconnection fault positioning and identifying method and system | |
| CN109633364A (en) | A kind of mutual inductor winding and fuse failure appraisal procedure, device and equipment | |
| CN109659917B (en) | Transient voltage-based multi-terminal flexible direct current line protection method and device | |
| CN106997016A (en) | A kind of low-voltage distributing line disconnection fault recognition methods and device | |
| CN109782122A (en) | A kind of detection method of S Injection Signal | |
| CN109709448A (en) | A kind of power distribution network single-phase high-impedance selection method based on synchronous extruding wavelet transformation | |
| CN207705796U (en) | A kind of multifunctional ligand power grid flexible ground device | |
| CN112485588A (en) | Permanent high-resistance fault section positioning method based on cascade H-bridge control | |
| Zhang et al. | Fault line selection using multiple disturbance characteristics of fault phase active grounding in resonant grounded distribution networks | |
| CN106569096B (en) | A kind of tuning on-line method of power distribution network single-phase fault | |
| CN205670180U (en) | Based on zero sequence transient analysis low current neutral grounding system fault alignment system |
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 | ||
| TR01 | Transfer of patent right | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20231023 Address after: 221116 Research Institute of China University of Mining and Technology, Tongshan University Road, Xuzhou City, Jiangsu Province Patentee after: CHINA University OF MINING AND TECHNOLOGY Address before: 221116 Research Institute of China University of Mining and Technology, Tongshan University Road, Xuzhou City, Jiangsu Province Patentee before: CHINA University OF MINING AND TECHNOLOGY Patentee before: SHENZHEN JINPA ELECTRIC POWER TECHNOLOGY CO.,LTD. |