CN104280644B - Direct-current transmission project typical transient fault recognizing method - Google Patents
Direct-current transmission project typical transient fault recognizing method Download PDFInfo
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- CN104280644B CN104280644B CN201410575160.9A CN201410575160A CN104280644B CN 104280644 B CN104280644 B CN 104280644B CN 201410575160 A CN201410575160 A CN 201410575160A CN 104280644 B CN104280644 B CN 104280644B
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- 238000000034 method Methods 0.000 title claims abstract description 25
- 230000005540 biological transmission Effects 0.000 title claims abstract description 24
- 230000001052 transient effect Effects 0.000 title claims abstract description 20
- 238000005070 sampling Methods 0.000 claims abstract description 6
- 238000000605 extraction Methods 0.000 claims abstract description 3
- 238000004458 analytical method Methods 0.000 claims description 14
- 239000012530 fluid Substances 0.000 claims description 14
- 239000000284 extract Substances 0.000 claims description 9
- 230000007935 neutral effect Effects 0.000 claims description 9
- 230000004907 flux Effects 0.000 claims description 6
- 238000012935 Averaging Methods 0.000 claims description 3
- 230000009471 action Effects 0.000 claims description 3
- 230000004069 differentiation Effects 0.000 claims description 3
- 238000004088 simulation Methods 0.000 claims description 3
- 230000004888 barrier function Effects 0.000 claims description 2
- 230000010363 phase shift Effects 0.000 claims description 2
- 239000004020 conductor Substances 0.000 claims 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 claims 1
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- 238000011835 investigation Methods 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 3
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- 230000008901 benefit Effects 0.000 description 2
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- 238000003379 elimination reaction Methods 0.000 description 2
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- 230000008569 process Effects 0.000 description 2
- 238000012216 screening Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
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Abstract
The invention discloses a direct-current transmission project typical transient fault recognizing method. The method is characterized by comprising the following steps that (1) data signals of a fault recorder are extracted and a fault electrode is judged; (2) direct-current-side voltage and current signals of the fault electrode are extracted, characteristic quantity extraction is conducted on waveforms, and at least one primary fault type is obtained after characteristic quantity matching is conducted according to a fault characteristic quantity library established in advance; (3) according to the waveform data time interval stored in a fault waveform sample library established in advance, sampling is conducted on the recorded waveforms of the fault electrode from the fault starting moment, sampling values are matched with waveform data corresponding to the primary fault types and located in the fault waveform sample library to obtain waveform similarity coefficients, and the fault type with the highest similarity is used as the final recognizing result. The direct-current transmission project typical transient fault recognizing method improves the fault checking efficiency and guarantees safe and stable operation of a direct-current transmission system.
Description
Technical field
The present invention relates to a kind of DC transmission engineering typical case's transient fault recognition methods.
Background technology
D.C. high voltage transmission (HVDC), is to have no induction reactance using galvanic current, capacitive reactance is also inoperative, no synchronously
The advantages of problem and the high-power remote direct current transportation that adopts.D.C. high voltage transmission is excellent in terms of long-distance and large-capacity power transmission
Gesture makes it be widely applied in China.Because HVDC Converters device category is various, major loop and
Control protection system complex structure, easily leads to DC system fault or stoppage in transit because of the apparatus insulated threat bearing overvoltage, sternly
The safe operation of weight threatening area electrical network.
The reason cause change of current station equipment overvoltage can be divided into three kinds, i.e. current conversion station AC fault, valve area fault and change
Stream station DC side fault, wherein, due to AC fault signature substantially, the change easily by AC voltage carries out failure classes
The identification of type.And for full voltage starting, ground connection polar curve open circuit, metallic return open circuit, inverter side locking and bypass to not unlocking, high
Current potential YY converter transformer valve side single-line to ground fault etc. is stood erectly due to controlling protection failure or the valve area that causes of short circuit, open circuit and the change of current
Stream side fault, its fault characteristic complexity is it is difficult to directly be differentiated to it.
High voltage direct current transmission project typically adopts polar curve (both positive and negative polarity of the direct current) voltage x current of fault fluid parameter to enter at present
The identification of row fault, and fault fluid parameter have recorded the analog quantity of primary side and secondary side many places and digital quantity waveform after fault,
Carry out needing during malfunction elimination to do substantial amounts of analysis work, operand is big, the investigation inefficiency of causing trouble.
Content of the invention
For the problems referred to above, the present invention provides a kind of DC transmission engineering typical case's transient fault recognition methods, makes full use of
The data of fault fluid parameter record, in conjunction with the feature of typical transient fault, forms Fault Identification algorithm, improves the investigation effect of fault
Rate is it is ensured that the safe and stable operation of DC transmission system.
For realizing above-mentioned technical purpose, reach above-mentioned technique effect, the present invention is achieved through the following technical solutions：
A kind of DC transmission engineering typical case's transient fault recognition methods is it is characterised in that comprise the steps：
(1) extract the data-signal of fault fluid parameter, carry out the differentiation of fault pole；
(2) extract the DC voltage of fault pole, current signal, Characteristic Extraction is carried out to waveform, according to setting up in advance
To carry out feature flux matched in fault characteristic value storehouse, obtain at least one preliminary fault type；
(3) according to the Wave data time interval of storage in the fault waveform Sample Storehouse set up in advance, the record to fault pole
Waveform is sampled at fault initial time, successively by sample value and fault waveform Sample Storehouse with preliminary fault type pair
The Wave data answered is mated, and asks for waveform similarity coefficient, using similarity highest fault type as the final knot identifying
Really.
Preferably, each step is specific as follows：
Step (1) specifically includes following steps：
Step 101：Extract the electrode line of fault fluid parameter output and the data-signal of negative line；
Step 102：Differentiate and there occurs phase shift locking or the extremely fault pole restarting action.
Step (2) specifically includes following steps：
Step 201：The slope variation of fault pole DC voltage and DC current is judged, obtains fault moment；
Step 202：Process the voltage data of polar curve using FFT；
Step 203：The analysis each DC voltage of instant of failure and the variation tendency of DC current；
Step 204：The overall variation trend of DC voltage and DC current after analysis fault；
Step 205：According to the result of step 202 to step 204, to carry out feature flux matched with fault characteristic value storehouse,
Obtain at least one preliminary fault type.
In step (3), ask for waveform similarity coefficient ρxyFormula as follows：
In formula, X (n) is sample waveform data, and Y (n) is wave-recording sampling data；
The coefficient correlation of each waveform is averaging, the maximum fault type of average correlation coefficient is the knot of final identification
Really.
This method makes full use of the data of fault fluid parameter record, using feature and and the fault wave of typical transient fault
The Waveform Matching of the sample waveform of shape Sample Storehouse quickly identifies fault, greatly improves the malfunction elimination efficiency of DC transmission engineering,
Algorithm is realized simple.
The invention has the beneficial effects as follows：Make full use of the data of fault fluid parameter record, in conjunction with the spy of typical transient fault
Levy, form Fault Identification algorithm, the investigation efficiency improving fault is it is ensured that the safe and stable operation of DC transmission system.
Brief description
Fig. 1 is a kind of schematic diagram of DC transmission engineering of present invention typical case's transient fault recognition methods.
Specific embodiment
With specific embodiment, technical solution of the present invention is described in further detail below in conjunction with the accompanying drawings, so that ability
The technical staff in domain can be better understood from the present invention and can be practiced, but illustrated embodiment is not as the limit to the present invention
Fixed.
Below, in detail taking the fault recorder data of the fault fluid parameter of ABB AB that Domestic Direct Current Transmission engineering is commonly used as a example
Carefully introduce DC transmission engineering Typical over-voltage transient fault (to specifically include：Under full voltage starting, the monopolar ground return method of operation
Inversion side joint ground polar curve open circuit, metallic return open circuit, rectification under rectification side ground connection polar curve open circuit, the monopolar ground return method of operation
Side high-end YY converter transformer valve side single-phase grounding fault, inverter side high-end YY converter transformer valve side single-phase grounding fault, inverse
Become side locking and bypass to not unlocking, line-to-ground short circuit) recognition methods, specifically include following steps, as shown in Figure 1：
(1) extract the data-signal of fault fluid parameter, carry out the differentiation of fault pole：
The output of fault fluid parameter comprises the data-signal of positive pole and negative pole, extracts the polar curve DC voltage of fault fluid parameter
With DC current signal.
For the typical transient fault causing current conversion station overvoltage, D.C. high voltage transmission break down after protection act in shifting
Phase locking or restart fault pole, differentiates, with DC current, the extremely fault pole that there occurs above action by DC voltage.
(2) typical transient fault tentatively identifies：
Extract the polar curve DC voltage (UDL) of fault pole, polar curve DC current (IDL), neutral bus voltage (UDN), in
Sexupara line current (IDNC), earth current (IDNE) signal, carry out slope variation analysis to polar curve DC voltage waveform, FFT divides
Analysis, the above variation tendency after instant of failure and fault for each parameter of analysis, form the characteristic quantity list of recorder data, according to
It is flux matched that the fault characteristic value storehouse set up in advance carries out feature, obtains at least one preliminary fault type, realizes to fault type
Screening, this time recognition result may not be unique.
Wherein, this method needs to set up a big Mishap Database in advance, specifically includes and comprises each typical fault
The fault characteristic value storehouse of feature and comprise each typical fault waveform fault waveform Sample Storehouse, fault characteristic value storehouse can be passed through
Mechanism and simulation study are set up, and fault waveform Sample Storehouse then can pass through RTDS (Real Time Digital
Simulator, real-time digital simulator) emulate, consider the actual electromagnetic transient simulation controlling protection feature or physical fault
Recorder data is set up.
Preferably, step (2) specifically includes following steps：
Step 201：The slope variation of fault pole DC voltage and DC current is judged, obtains fault moment；
Step 202：Process the voltage data of polar curve, i.e. UDL data using FFT；
Step 203：The variation tendency of the analysis each DC voltage of instant of failure and DC current, that is, analysis instant of failure UDL,
The variation tendency of IDL, UDN, IDNC, IDNE；
Step 204：After analysis fault, DC voltage and the overall variation trend of DC current, that is, analyze the whole record ripple time
The overall variation trend of UDL, IDL, UDN, IDNC, IDNE in section；
Step 205：According to the result of step 202 to step 204, to carry out feature flux matched with fault characteristic value storehouse,
Obtain at least one preliminary fault type.
Judge that the algorithm of preliminary fault type is as follows：
1) if the neutral bus electric current in recorder data is less than 0.1p.u., i.e. IDNC within the whole analysis period<
0.1p.u., then for full voltage starting fault；
2) if containing 50HZ component in polar curve DC voltage, that is, the frequency spectrum of UDL has 50HZ component, and instant of failure inversion
Side pole line voltage rises, polar curve electric current and neutral bus electric current all decline, then bypass former to not unlocking for inverter side locking
Barrier；
3) if instant of failure inverter side line voltage, polar curve electric current and neutral bus electric current all decline, i.e. inverter side
UDL, IDL, IDNC decline, then high-end for rectification side ground connection polar curve open fault, rectification side under the monopolar ground return method of operation
YY converter transformer valve side single-phase grounding fault or metallic return open fault；
4) if inverter side earthing pole line current drops to 0 within 1ms, i.e. IDNE=0, then run for monopolar ground return
Inverter side ground connection polar curve open fault under mode；
5) if neutral bus electric current drops to 0 within 1ms, i.e. IDNC=0, then for inverter side high potential YY converter transformer valve
Side single-phase grounding fault；
6) if direct-current polar voltage, electric current deteriorate to less than 0.1p.u., that is, UDL and IDL drops to less than 0.1p.u., and
Rise again after a period of time or restart, then for line-to-ground short trouble.
(3) final identification types are obtained by Waveform Matching：
According to the Wave data time interval of storage in the fault waveform Sample Storehouse set up in advance, the record ripple ripple to fault pole
Shape is sampled at fault initial time, total time length be consistent with the time duration of sample waveform of storage,
Successively sample value is mated with Wave data corresponding with preliminary fault type in fault waveform Sample Storehouse, can be according to following
Formula carries out waveform similarity coefficient ρxyAsk for,
In formula, X (n) is sample waveform data, and Y (n) is wave-recording sampling data.
The coefficient correlation of each waveform is averaging, the maximum fault type of average correlation coefficient is the knot of final identification
Really, will similarity highest fault type as final identification fault type.
Compared to voltage, the electric current of direct-current polar of only sampling in the past, carry out Fault Identification side by complicated time frequency analysis
Method, this recognition methods takes full advantage of the feature of fault itself, by the fault signature of faults topology information, fault is entered
Row Primary Location.Make full use of the existing data of fault fluid parameter, fault waveform carried out with Waveform Matching, algorithm is realized simply,
Improve the Fault Identification degree of accuracy, and in the case that fault type preliminary screening has been carried out by fault signature, recognition effect
Significantly, improve the investigation efficiency of fault it is ensured that the safe and stable operation of DC transmission system.
These are only the preferred embodiments of the present invention, not thereby limit the present invention the scope of the claims, every using this
Equivalent structure or equivalent flow conversion that bright specification and accompanying drawing content are made, or it is related to be directly or indirectly used in other
Technical field, be included within the scope of the present invention.
Claims (4)
1. a kind of DC transmission engineering typical case's transient fault recognition methods is it is characterised in that comprise the steps：
(1) extract the data-signal of fault fluid parameter, carry out the differentiation of fault pole；
(2) extract DC voltage, the current signal of fault pole, Characteristic Extraction is carried out to waveform, according to the event set up in advance
It is flux matched that barrier characteristic quantity storehouse carries out feature, obtains at least one preliminary fault type；
(3) according to the Wave data time interval of storage in the fault waveform Sample Storehouse set up in advance, the record ripple ripple to fault pole
Shape is sampled at fault initial time, successively that sample value is corresponding with preliminary fault type with fault waveform Sample Storehouse
Wave data is mated, and asks for waveform similarity coefficient, using similarity highest fault type as the final result identifying；
Step (2) specifically includes following steps：
Step 201：The slope variation of fault pole DC voltage and DC current is judged, obtains fault moment；
Step 202：Using FFT handling failure pole DC voltage data；
Step 203：The analysis each DC voltage of instant of failure and the variation tendency of DC current；
Step 204：The overall variation trend of DC voltage and DC current after analysis fault；
Step 205：According to the result of step 202 to step 204, to carry out feature flux matched with fault characteristic value storehouse, obtains
At least one preliminary fault type；
Judge that the algorithm of preliminary fault type is as follows：
1) if the neutral bus electric current in recorder data is less than 0.1p.u. within the whole analysis period, for full voltage starting fault；
2) if in polar curve DC voltage contain 50HZ component, and instant of failure inverter side line voltage rise, polar curve electric current with
And neutral bus electric current all declines, then bypass to not unlocking fault for inverter side locking；
3) if inverter side polar curve is all declined with the electric current of the voltage, electric current and ground connection polar curve of the neutral conductor, return for one pole the earth
Rectification side ground connection polar curve open fault, rectification side high-end YY converter transformer valve side single-phase grounding fault or gold under the line method of operation
Belong to loop line open fault；
4) if inverter side earthing pole line current drops to 0, for inversion under the monopolar ground return method of operation in 1ms after a failure
Side joint ground polar curve open fault；
5) if neutral bus electric current drops to 0 within 1ms after a failure, connect for inverter side high potential YY converter transformer valve side is single-phase
Ground short circuit fault；
6) if direct-current polar voltage x current deteriorates to less than 0.1p.u., and rise again or restart after a period of time, then for
Line-to-ground short trouble；
2. a kind of DC transmission engineering typical case's transient fault recognition methods according to claim 1 is it is characterised in that step
(3), in, ask for waveform similarity coefficient ρxyFormula as follows：
In formula, X (n) is sample waveform data, and Y (n) is wave-recording sampling data；
The similarity factor of each waveform is averaging, the maximum fault type of average similarity coefficient is the result of final identification.
3. a kind of DC transmission engineering typical case's transient fault recognition methods according to claim 1 is it is characterised in that step
(1) following steps are specifically included：
Step 101：Extract the electrode line of fault fluid parameter output and the data-signal of negative line；
Step 102：Differentiate and there occurs phase shift locking or the extremely fault pole restarting action.
4. a kind of DC transmission engineering typical case's transient fault recognition methods according to claim 13 any one, it is special
Levy and be, emulated by RTDS, consider that the electromagnetic transient simulation of actual control protection feature or physical fault recorder data are built
Vertical fault waveform Sample Storehouse.
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| US9787081B2 (en) * | 2015-02-27 | 2017-10-10 | Electronic Systems Protection, Inc. | Overvoltage notching of electrical swells |
| CN106441843B (en) * | 2016-09-19 | 2019-09-20 | 南京科远自动化集团股份有限公司 | A kind of rotating machinery fault method for waveform identification |
| CN108344904A (en) * | 2017-03-23 | 2018-07-31 | 长沙理工大学 | A kind of direct current cables malfunction monitoring and new method for identifying |
| CN107526007B (en) * | 2017-08-14 | 2019-09-13 | 深圳市中业智能系统控制有限公司 | The recognition methods of fault type and device |
| CN107727963B (en) * | 2017-10-10 | 2019-08-09 | 中国南方电网有限责任公司超高压输电公司昆明局 | The electrical quantities measurement fault distinguishing method verified based on historical data sample and algorithm |
| CN111157812A (en) * | 2019-12-28 | 2020-05-15 | 杭州拓深科技有限公司 | Power equipment fault monitoring method based on electromagnetic induction |
| CN113379193B (en) * | 2021-05-11 | 2023-04-18 | 国网河北省电力有限公司邢台供电分公司 | Power grid operation inspection control method and device and terminal equipment |
| CN113466550A (en) * | 2021-08-11 | 2021-10-01 | 国网山西省电力公司 | Electric energy meter |
| CN113884821A (en) * | 2021-08-23 | 2022-01-04 | 华能国际电力江苏能源开发有限公司南通电厂 | Line fault distance determination method and equipment based on traveling wave method |
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| US20130193766A1 (en) * | 2012-01-31 | 2013-08-01 | Atlantic Grid Operations A., Llc | Control and protection of a dc power grid |
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