CN109885418A - Site tranformer protection anti-interference method based on sampling disturbance filtering - Google Patents
Site tranformer protection anti-interference method based on sampling disturbance filtering Download PDFInfo
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- CN109885418A CN109885418A CN201910049125.6A CN201910049125A CN109885418A CN 109885418 A CN109885418 A CN 109885418A CN 201910049125 A CN201910049125 A CN 201910049125A CN 109885418 A CN109885418 A CN 109885418A
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- 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
- Y04—INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
- Y04S—SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
- Y04S40/00—Systems for electrical power generation, transmission, distribution or end-user application management characterised by the use of communication or information technologies, or communication or information technology specific aspects supporting them
- Y04S40/12—Systems for electrical power generation, transmission, distribution or end-user application management characterised by the use of communication or information technologies, or communication or information technology specific aspects supporting them characterised by data transport means between the monitoring, controlling or managing units and monitored, controlled or operated electrical equipment
- Y04S40/124—Systems for electrical power generation, transmission, distribution or end-user application management characterised by the use of communication or information technologies, or communication or information technology specific aspects supporting them characterised by data transport means between the monitoring, controlling or managing units and monitored, controlled or operated electrical equipment using wired telecommunication networks or data transmission busses
Abstract
The invention discloses a kind of site tranformer protection anti-interference methods based on sampling disturbance filtering; analog quantity information is obtained using four times of high-speed sampling for being at least protection actual samples rate; sampling disturbance filtering is carried out to the sampled value after analog-to-digital conversion; unusual waveforms identification is carried out using the variation of sampling slope; it is synchronous with HSR looped network reception data progress data after sampling disturbance filtering; data use after synchronizing to this handset protection algorism, while being sent to other handsets by HSR looped network.Fast response time of the present invention, adaptable, Anti-interference algorithm is not related with HSR looped network data and protection algorism directly in sampled value processing links, does not influence site Power Transformer Protection Algorithm.
Description
Technical field
The present invention relates to a kind of site tranformer protection anti-interference methods based on sampling disturbance filtering, belong to relay guarantor
Protect technical field.
Background technique
Site protection characterized by " sampling digitizing, protection site, element protection private network, information sharing "
New technology is the major technique direction of following State Grid Corporation of China's intelligent substation.Low-power chip integrated technology, fiber optic communication
The breakthrough of the key technologies such as the development of technology and device electromagnetic compatibility, high protection, thermal design, is site protection scheme
Implementation provides technical foundation.Site protection is arranged on the spot close to primary equipment, is directly tripped using cable sampling, cable,
Cable length and intermediate link are reduced, the quick-action and reliability of relay protection are promoted；It is designed based on nuclear interface standardizing, using mark
Quasi- connector realizes batch production debugging, the maintenance of modularization installation and replacement formula of protective device, reduces secondary device installation, adjusts
Examination and repair time promote work quality and efficiency, shorten power off time.
Referring to Fig. 1, tranformer protection is connected and composed by multiple protection handsets by independent Double-direction double-ring net, protects handset
It is configured by side.Tranformer protection handset acquires the analog quantity and switching value of this side, exports the sequential trip outlet of this side switch.Become
Depressor protects handset to receive the analog quantity and switching value information of other protection handset acquisitions by element protection HSR looped network, respectively protects
Protect all defencive functions of handset complete independently.Protection handset is arranged on the spot close to primary equipment, is easy to be operated by primary equipment
And the influence of earth mat interference, so that sampled data disturbs, sampled data will not only be used to the protection of this handset, also be wanted
It is used by communication mode to other handsets, if going out to manage without algorithm, sampled data is extremely extremely easy in an interference situation is led
Cause the more handset malfunctions of tranformer protection.
So site tranformer protection needs a kind of jamproof algorithm at present from the point of view of status, disturbed to solve sampling
The dynamic influence to protection algorism, to improve the reliability of site tranformer protection.
Summary of the invention
The technical problem to be solved by the present invention is to overcome the deficiencies of existing technologies, provide a kind of based on sampling disturbance filtering
Site tranformer protection anti-interference method, wanted with meeting site tranformer protection for reliability in terms of electromagnetic compatibility
It asks.
In order to solve the above technical problems, to provide a kind of site tranformer protection based on sampling disturbance filtering anti-by the present invention
Interference method, comprising the following steps:
1) site sample rate current voltage data；
2) abnormal disturbances differentiation is carried out to the sampled data of the step 1)；
3) interpolation processing is carried out to sampling abnormal data；
4) synchronism output site sampled data and external input HSR data.
In aforementioned step 1), using multiple AD modulus conversion chip sample rate current voltage datas, multiple AD analog-to-digital conversions
The chip conversion and control and data reading mode concurrent using multiple groups, conversion start while enabling the busy of AD modulus conversion chip
Indication signal obtains corresponding sampled data in real time after AD analog-to-digital conversion, and analog-to-digital conversion is as follows:
Wherein, SoTo export digital quantity, V after AD conversioniFor input voltage analog quantity, VmaxFor input voltage range.
In aforementioned step 1), site sampling rate is at least four times of protection actual samples rate, postpones 1~4
Sampled data window.
The real-time monitoring AD modulus conversion chip power supply above-mentioned in sampling process and sampling communication process, turn in AD modulus
When changing relatively low chip power or sampling communication abnormality, sample error mark is marked.
In aforementioned step 2), abnormal disturbances differentiation is carried out to sampled data, comprising the following steps:
21), judge whether present sample data are effective, and determination method is as follows:
Wherein, SnFor sampled instantaneous value, In is rated current；
22), in the case where sampled data has stream mode, sampling abnormality is differentiated, specific as follows:
22-1) calculate the slope of sampled point:
Kn=Sn-Sn-1
Wherein, KnFor the slope of sampled point n, SnFor the sampled instantaneous value of sampled point n, Sn-1For the sampling wink of sampled point n-1
Duration；
22-2) calculate the slope variation amount of sampled point:
ΔKn=| Kn-Kn-1|
Wherein, Δ KnFor the slope variation amount of sampled point n, KnFor the slope of sampled point n, Kn-1For the slope of sampled point n-1；
22-3) determine whether sampled point is abnormal, and criterion is as follows according to the slope variation amount of sampled point:
Meeting above formula then is sampling noise spot.
In aforementioned step 3), when the step 2) monitors sampling noise spot, whether judgement sampled value first can be inserted
Value restores sampling noise spot using cubic spline interpolation when sampling noise spot meets interpolation condition；When sampling is interfered
When point is unsatisfactory for interpolation condition, real-time set sample error mark.
Interpolation condition above-mentioned are as follows: if preceding several continuous sampling data bulks of current data sample point are less than or equal to 4
And preamble continuous effective sampled value quantity is more than or equal to 2, then this sampled point can interpolation.
In aforementioned step 4), after getting site sampled data and external input HSR data, each sampling output is corrected
The interruption pulse of delay starts to reset transmitting counter in each interruption pulse, and follows the crystal oscillator period from increasing, and works as transmission
When counter increases to consistent with practical sending instant, export corresponding sample point data, realize site sampled data with
The time domain uniformity of external input HSR data.
Advantageous effects of the invention:
(1), fast response time improves the sampling rate of system, and actual sample rate is four times of protection algorism sample rate, resists
Algorithm of interference is implemented in 4 points, will not influence the response speed of entire protection algorism.
(2), precision is high, and using cubic spline interpolation, the sampling precision of whole system will not be sacrificed in interference treatment process.
(3), adaptable, Anti-interference algorithm is directly in sampled value processing links, with HSR looped network data and protection algorism
It is not related, site Power Transformer Protection Algorithm is not influenced.
(4), synchronization accuracy is high, carries out sample interpolation using high sampling rate and synchronizes, and interpolation, which is not sacrificed, can survey frequency in range
Rate precision.
(5), high reliablity carries out sampling abnormal judgement using slope variation amount, not will lead to erroneous judgement in transient process and adopts
Sample is abnormal.
Detailed description of the invention
Fig. 1 is distributed local tranformer protection schematic diagram；
Fig. 2 is the flow chart of the method for the present invention；
Fig. 3 is the differentiation of sampling abnormal disturbances and process flow diagram in the method for the present invention.
Specific embodiment
The invention will be further described below.Following embodiment is only used for clearly illustrating technical side of the invention
Case, and not intended to limit the protection scope of the present invention.
The present invention provides a kind of site tranformer protection anti-interference method based on sampling disturbance filtering, using at least
Four times of high-speed sampling of actual samples rate is protected to obtain analog quantity information；Sampling is carried out to the sampled value after analog-to-digital conversion to disturb
Dynamic filtering carries out unusual waveforms identification using the variation of sampling slope；Data are received with HSR looped network after sampling disturbance filtering to carry out
Data are synchronous；Data use after synchronizing to this handset protection algorism, while being sent to other handsets by HSR looped network.
Referring to fig. 2, the specific steps are as follows:
Step 1: site high-speed sampling Current Voltage value
Using the AD modulus conversion chip of high speed, the AD sampling rate based on 800 points/cycle, has quick digitlization
Ability in sampling avoids original signal high fdrequency component caused by analog loopback sample rate deficiency and lacks, and sampling precision error is larger
Or the abnormal conditions such as sampled data is unstable, while the realization precision of back-end algorithm can be effectively improved.
To improve AD sample frequency, link sample mode without using daisy chain between multi-disc AD, and uses multiple groups concurrent fashion
Conversion and control and reading data, conversion starts the busy indication signal of enabled AD conversion simultaneously, real-time after AD conversion
Obtain corresponding sampled data.AD conversion formula is as follows:
Wherein: SoTo export digital quantity, V after AD conversioniFor input voltage analog quantity, VmaxFor input voltage range.
It is at least four times for protecting actual samples rate in the present invention to high-speed sampling input sample rate, postpones 1~4
Sampled data window protects actual samples rate generally in 24 points/cycle between 96 points/cycle.
Step 2: abnormal disturbances differentiation is carried out to sampled data
The sample sequence of step 1 translation cache is analyzed, fast-pulse interference is supervised by software mode
It surveys, preferably antithesis shows pulse feature interference and inhibited, protection algorism malfunction caused by preventing the abnormal big value of instantaneous sampling from disturbing
The problems such as.Sampling Disturbance Detection processing is carried out to sampled point, sampled point for noise spot, passes through subsequent algorithm interpolation if judging
Data substitute abnormal sample data.
Fig. 3 is participated in, this step carries out abnormal disturbances differentiation to sampled data and is divided into two parts:
21), judge whether present sample data are effective, and determination method is as follows:
Wherein: SnFor sampled instantaneous value, In is rated current.
22), when sampling has stream, sampling abnormality is differentiated, (without processing when no stream) specific as follows:
22-1) calculate the slope of sampled point:
Kn=Sn-Sn-1
Wherein: KnFor the slope of sampled point n, SnFor the sampled instantaneous value of sampled point n, Sn-1For the sampling wink of sampled point n-1
Duration.
22-2) calculate the slope variation amount of sampled point:
ΔKn=| Kn-Kn-1|
Wherein: Δ KnFor the slope variation amount of sampled point n, KnFor the slope of sampled point n, Kn-1For the slope of sampled point n-1.
22-3) judge sample error mark, if it is reset samples error flag, it is no longer necessary to be judged, directly
Carry out protection blocking；If it is not, then determining whether sampled point is abnormal according to the slope variation amount of sampled point, if slope variation amount
Big but variation is stablized, and is sampled for higher hamonic wave；If slope variation amount is greatly and the slope variation amount of former point is little, for sampling
Noise spot.Sample error mark is that then sampled data is insincere for the exception information that is provided according to the working condition of A/D chip, no longer
Judged, directly progress protection blocking.It is as follows to sample Anomaly criterion:
Meeting above formula then is sampling noise spot.
Real-time monitoring AD power supply and AD sample communication process to this step in sampling process simultaneously, relatively low in A/D module power supply
Or when with A/D module communication abnormality, sample error mark is marked.Increase protective device itself to the fault-tolerant ability of interference signal.
Step 3: abnormal sample processing
When step 2 monitor sampling noise spot when, first judgement sampled value whether can interpolation, sampling noise spot meet
When interpolation condition, sampling noise spot is restored by high-precision interpolation algorithm, is fitted crude sampling information to greatest extent
Data；When sampling noise spot is unsatisfactory for interpolation condition, real-time set sample error mark, it is invalid caused by sampling disturbance to avoid
Influence of the sampled data to Power Transformer Protection Algorithm.
Interpolation condition are as follows: if sampled value (preceding several continuous sampling numbers of current data sample point of the continuous interpolation of preamble
According to) quantity be less than or equal to 4 and preamble continuous effective sampled value quantity be more than or equal to 2, then this point sampling can interpolation, otherwise, effectively
Sample information is insufficient, unusable interpolation algorithm.
Interpolation algorithm is as follows:
Interpolation is carried out to original sampled signal using software interpolation algorithm, by the refresh rate of reality output data, to original
Sampling be fitted interpolation calculation, obtain final sampling output discrete series.
Cubic spline interpolation calculating is carried out to the sampled value of site tranformer protection, the length of input array X and Y are n,
x0<x1<…<xn-1, as shown in following equations:
f(xi)=yi
Interpolating function g (x) is piecewise function in following equations:
Function pi(x) it is three rank multinomials for meeting following condition:
g(xi)=yi=pi(xi)
In xiThe single order and second dervative continuously located are continuous, i=1 ..., n -2,
g′(xi)=p 'i(xi)=p 'i-1(xi)
g″(xi)=p "i(xi)=p "i-1(xi)
g″(xi) be Cubic Spline second dervative.In section [xi,xi+1], following equalities are output interpolation y:
Y=Ayi+Byi+1+Cy″i+Dy″i+1
Wherein:
B=1-A
Step 4: multi-source sampling data synchronization output
The analog quantity sampling of site tranformer protection is that time domain is continuous, there are the analog-digital conversion data sequences of error for codomain
Column, and externally input HSR sampling is time domain there are discretization error, the lesser digital quantity sampling of codomain error, the two when
There are essential distinction in the characteristic of domain, system frequency, sampling rate, in terms of there may be differences.Therefore, it needs
The time-domain transmission feature of physics sampling and digitized sampling is merged, realizes sampled data on the spot and external input HSR data
Synchronism output control.Specific implementation are as follows:
After getting sampled data on the spot and outside HSR sampled data, by the interruption arteries and veins for correcting each sampling output delay
Punching, realizes the synchronously control between different sampled datas.The minimum resolution of output interruption pulse is determined by onboard crystal oscillator, and by being
The unified adjusting of synchronization pulse per second (PPS) inside system, the first interruption pulse in each synchronizing cycle is by synchronizing pulse per second (PPS) rising edge hair
It rises, remaining interruption pulse is controlled by the interval counter in sampling period.Each interruption pulse start transmitting counter is clear
Zero, and follow the crystal oscillator period from increase, when transmitting counter increases to it is consistent with practical sending instant when, export corresponding sampled point
Data, it is ensured that the time domain uniformity of sampled data.
By step 1 to step 4, the sampling anti-interference process of site Power Transformer Protection Algorithm is realized, is improved
Relevant device reliability of operation and stability at the scene.
The above is only a preferred embodiment of the present invention, it is noted that for the ordinary skill people of the art
For member, without departing from the technical principles of the invention, several improvement and deformations can also be made, these improvement and deformations
Also it should be regarded as protection scope of the present invention.
Claims (8)
1. the site tranformer protection anti-interference method based on sampling disturbance filtering, which comprises the following steps:
1) site sample rate current voltage data；
2) abnormal disturbances differentiation is carried out to the sampled data of the step 1)；
3) interpolation processing is carried out to sampling abnormal data；
4) synchronism output site sampled data and external input HSR data.
2. the site tranformer protection anti-interference method according to claim 1 based on sampling disturbance filtering, feature
It is, in the step 1), using multiple AD modulus conversion chip sample rate current voltage datas, multiple AD modulus conversion chips are adopted
With the concurrent conversion and control of multiple groups and data reading mode, conversion starts while the busy instruction letter of enabled AD modulus conversion chip
Number, obtain corresponding sampled data in real time after AD analog-to-digital conversion, analog-to-digital conversion is as follows:
Wherein, SoTo export digital quantity, V after AD conversioniFor input voltage analog quantity, VmaxFor input voltage range.
3. the site tranformer protection anti-interference method according to claim 1 based on sampling disturbance filtering, feature
It is, in the step 1), site sampling rate is at least four times of protection actual samples rate, postpones 1~4 hits
According to window.
4. the site tranformer protection anti-interference method according to claim 1 based on sampling disturbance filtering, feature
It is, real-time monitoring AD modulus conversion chip power supply and sampling communication process in sampling process, in AD modulus conversion chip electricity
When source is relatively low or samples communication abnormality, sample error mark is marked.
5. the site tranformer protection anti-interference method according to claim 1 based on sampling disturbance filtering, feature
It is, in the step 2), abnormal disturbances differentiation is carried out to sampled data, comprising the following steps:
21), judge whether present sample data are effective, and determination method is as follows:
Wherein, SnFor sampled instantaneous value, In is rated current；
22), in the case where sampled data has stream mode, sampling abnormality is differentiated, specific as follows:
22-1) calculate the slope of sampled point:
Kn=Sn-Sn-1
Wherein, KnFor the slope of sampled point n, SnFor the sampled instantaneous value of sampled point n, Sn-1For the sampled instantaneous value of sampled point n-1；
22-2) calculate the slope variation amount of sampled point:
ΔKn=| Kn-Kn-1|
Wherein, Δ KnFor the slope variation amount of sampled point n, KnFor the slope of sampled point n, Kn-1For the slope of sampled point n-1；
22-3) determine whether sampled point is abnormal, and criterion is as follows according to the slope variation amount of sampled point:
Meeting above formula then is sampling noise spot.
6. the site tranformer protection anti-interference method according to claim 1 based on sampling disturbance filtering, feature
Be, in the step 3), when the step 2) monitor sampling noise spot when, first judgement sampled value whether can interpolation,
When sampling noise spot meets interpolation condition, sampling noise spot is restored using cubic spline interpolation；When sampling noise spot not
When meeting interpolation condition, real-time set sample error mark.
7. the site tranformer protection anti-interference method according to claim 6 based on sampling disturbance filtering, feature
It is, the interpolation condition are as follows: if preceding several continuous sampling data bulks of current data sample point are less than or equal to 4 and preamble
Continuous effective sampled value quantity is more than or equal to 2, then this sampled point can interpolation.
8. the site tranformer protection anti-interference method according to claim 1 based on sampling disturbance filtering, feature
It is, in the step 4), after getting site sampled data and external input HSR data, corrects each sampling output delay
Interruption pulse, start to reset transmitting counter in each interruption pulse, and follow the crystal oscillator period from increase, when send count
When device increases to consistent with practical sending instant, corresponding sample point data is exported, realizes site sampled data and outside
Input the time domain uniformity of HSR data.
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| CN104701806A (en) * | 2015-03-19 | 2015-06-10 | 西电通用电气自动化有限公司 | Processing method of abnormal sampling point in relay protection |
| CN106385029A (en) * | 2016-08-29 | 2017-02-08 | 西电通用电气自动化有限公司 | Filtering method of surge immunity sampling |
| CN106896338A (en) * | 2017-04-17 | 2017-06-27 | 南京国电南自电网自动化有限公司 | A kind of system that abnormal data is recognized based on combining unit |
| CN107782992A (en) * | 2017-09-01 | 2018-03-09 | 许昌许继软件技术有限公司 | A kind of Wave record method and device based on transformer station's antisurge interference |
| CN108183463A (en) * | 2017-12-29 | 2018-06-19 | 长园深瑞继保自动化有限公司 | The method of intelligent substation transformer ratio differential protection faulty action preventing |
-
2019
- 2019-01-18 CN CN201910049125.6A patent/CN109885418B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104701806A (en) * | 2015-03-19 | 2015-06-10 | 西电通用电气自动化有限公司 | Processing method of abnormal sampling point in relay protection |
| CN106385029A (en) * | 2016-08-29 | 2017-02-08 | 西电通用电气自动化有限公司 | Filtering method of surge immunity sampling |
| CN106896338A (en) * | 2017-04-17 | 2017-06-27 | 南京国电南自电网自动化有限公司 | A kind of system that abnormal data is recognized based on combining unit |
| CN107782992A (en) * | 2017-09-01 | 2018-03-09 | 许昌许继软件技术有限公司 | A kind of Wave record method and device based on transformer station's antisurge interference |
| CN108183463A (en) * | 2017-12-29 | 2018-06-19 | 长园深瑞继保自动化有限公司 | The method of intelligent substation transformer ratio differential protection faulty action preventing |
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