CN102809679A - Method and device for sampling electric monitoring signal - Google Patents
Method and device for sampling electric monitoring signal Download PDFInfo
- Publication number
- CN102809679A CN102809679A CN2012102792190A CN201210279219A CN102809679A CN 102809679 A CN102809679 A CN 102809679A CN 2012102792190 A CN2012102792190 A CN 2012102792190A CN 201210279219 A CN201210279219 A CN 201210279219A CN 102809679 A CN102809679 A CN 102809679A
- Authority
- CN
- China
- Prior art keywords
- sampling
- electric power
- monitoring signal
- power monitoring
- frequency
- 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.)
- Pending
Links
Images
Abstract
The invention discloses a method and a device for sampling an electric monitoring signal. The method comprises the following steps: S1, receiving an electric monitoring signal, and sampling the electric monitoring signal at a fixed sampling rate; S2, calculating the frequency f of the sampled electric monitoring signal, and determining the position of a fitting point, if the number of actual sampling points of each circle of waves of the frequency is supposed to be N, then determining positions of N fitting points are determined, wherein N is a natural number; and S3, calculating numerical values of N fitting points. At the fixed sampling rate, sampling data which can be continued periodically are generated in a mode that sampling points are fitted, and the sampling data are used in a DFT (discrete fourier transform) algorithm; and compared with a variable sampling rate DFT algorithm with fixed calculation points, the technical scheme is more universal and applicable.
Description
Technical field
The present invention relates to data processing field, relate in particular to a kind of electric power monitoring signals sampling method and apparatus.
Background technology
Existing power monitoring terminal equipment generally includes the sample circuit of analog voltage signal, analog current signal and the Treatment Analysis of correlated sampling data.In these Treatment Analysis algorithms; DFT (Discrete Fourier Transform; DFT) is rudimentary algorithm; The real part and the imaginary part of analog voltage signal and analog current signal can be obtained through the DFT algorithm, on this basis, its amplitude and phase value or the like can be further calculated.As everyone knows, the DFT algorithm has a pacing items, and the data that are used to calculate exactly must satisfy the characteristic of periodic extension, otherwise its result of calculation is inaccurate; In addition, the electric power monitoring terminal device also universal demand can in the certain frequency scope, satisfy certain computational accuracy.In order to satisfy above 2 points, existing power monitoring terminal equipment all adopts the variable sampling rate DFT algorithm of fixedly computing under counting usually, just passes through the change sampling rate, makes the sampled data that is used for calculating satisfy the characteristic of periodic extension.
Variable sampling rate DFT algorithm under fixedly computing is counted; It generally is the actual operating frequency of obtaining one tunnel analog quantity (a for example phase voltage) through hardware approach or software approach earlier; Adjust sampling rate according to this frequency; Like this, under different analog quantity frequencies, it is changeless that the sampled data of guaranteeing each cycle is counted.Adopt this method, can satisfy the requirement of electric power monitoring terminal device to a certain extent, but some is not enough below existing: the signal-processing board that (1) is present; For example DSP, ARM chip or the like; Generally need to gather the multichannel processing signals, and if have two with Up Highway UHW, its frequency is different; At this moment, said method just is difficult to meet design requirement; (2) if a plurality of signal-processing boards are arranged, also there is above-mentioned similar problem, also can causes the problem of power calculation synchronous processing simultaneously; (3) said method requires sampled signal controlled by CPU, if this CPU breaks down, can cause operation of entire equipment unusual; In addition, it is also more to influence the factor of sampling precision; Sometimes, variable sampling rate itself is also influential to other algorithm, so should not adopt variable sampling rate under some situation.
Summary of the invention
The technical matters that the present invention will solve is, should not adopt the defective of variable sampling rate to some situation in the prior art, and a kind of electric power monitoring signals sampling method and apparatus with ubiquity and applicability is provided.
The technical solution adopted for the present invention to solve the technical problems is: a kind of electric power monitoring signals sampling method is provided, said method comprising the steps of:
S1. receive the electric power monitoring signal, and adopt fixed sample rate that said electric power monitoring signal is sampled;
S2. the frequency f of the electric power monitoring signal behind the calculating sampling, and the position of definite match point, suppose this frequency f weekly the actual samples of ripple count and be N, then confirm the position of N match point, wherein, N is a natural number;
S3. calculate the numerical value of N match point.
Preferably, further comprising the steps of after the said step S3:
S4. the numerical applications of a said N match point is carried out various fundamental operations in the DFT algorithm.
Preferably, said various fundamental operation comprises real part, imaginary part, amplitude and the phase place of calculating electric parameter; Wherein, said electric parameter comprises analog voltage signal and analog current signal.
Preferably, the method for the frequency of the electric power monitoring signal behind the calculating sampling comprises hardware approach and software approach among the said step S2.
Preferably, said hardware approach is specially: through the electric power monitoring signal after the sampling is carried out the shaping conversion, CPU detects the frequency that shaped pulse comes the electric power monitoring signal behind the calculating sampling at interval through timer.
Preferably, said software approach is specially: through the frequency of the electric power monitoring signal behind the time interval at the zero point calculating sampling of the electric power monitoring signal after the sampling.
Preferably, the position of definite match point specifically may further comprise the steps among the said step S2:
S21. confirm the position of actual samples point, suppose that the SI corresponding to said fixed sample rate is 1/ (f0*N), then the position of actual samples point is Y [n0]=n0/ (f0*N), n0=0; 1,2 ... N, N+1 ... Wherein, N is a standard ripple sampling number weekly, and f0 is a standard power monitor signal frequency;
S22. confirm the position of match point according to frequency f, suppose that the SI corresponding to said frequency f is 1/ (f*N), then the position of match point is X [n]=n/ (f*N), wherein, n=0,1,2 ..., N.
Preferably, said step S3 specifically may further comprise the steps:
S31. calculate the linear scaling constant k according to the position X [n] of said match point and two adjacent points of position Y [n0] of being in actual samples point;
S32. according to the numerical value of linear scaling constant k with N the match point of neighbouring sample value The Fitting Calculation of reality.
The present invention also provides a kind of sampling apparatus of electric power signal, and said device comprises successively the sampling unit that connects, confirms unit and computing unit; Wherein:
Sampling unit is used to receive the electric power monitoring signal, and adopts fixed sample rate that said electric power monitoring signal is sampled;
Confirm the unit, be used for the frequency f of the electric power monitoring signal behind the calculating sampling, and the position of definite match point, suppose this frequency f weekly the actual samples of ripple count and be N, then confirm the position of N match point, wherein, N is a natural number;
Computing unit is used to calculate the numerical value of N match point.
Preferably, said device also comprises the DFT algorithm unit that is used for the numerical applications of a said N match point is carried out in the DFT algorithm various fundamental operations that is connected with said computing unit.
The technical scheme of embodiment of the present invention; Has following beneficial effect: under the condition of fixed sample rate; But produce the sampled data of periodic extension through the mode of match sampled point; And this sampled data is used for the DFT algorithm, this technical scheme is compared with the variable sampling rate DFT algorithm under fixedly computing is counted, and has more ubiquity and applicability.
Description of drawings
To combine accompanying drawing and embodiment that the present invention is described further below, in the accompanying drawing:
Fig. 1 is the process flow diagram of electric power monitoring signals sampling method of the present invention;
Fig. 2 is a particular flow sheet of confirming the position of match point among the step S2 according to the invention;
Fig. 3 is the particular flow sheet of step S3 of the present invention;
Fig. 4 is the structural representation of electric power monitoring signals sampling device of the present invention.
Embodiment
In order to make the object of the invention, technical scheme and advantage clearer,, the present invention is further elaborated below in conjunction with accompanying drawing and embodiment.Should be appreciated that specific embodiment described herein only in order to explanation the present invention, and be not used in qualification the present invention.
See also Fig. 1, Fig. 1 is the process flow diagram of electric power monitoring signals sampling method of the present invention, and is as shown in Figure 1, said method comprising the steps of:
In step S1, receive the electric power monitoring signal, and adopt fixed sample rate that said electric power monitoring signal is sampled, sampling rate is the implication of SF, and the implication of this fixed sample rate is and does not change SF.
In step S2, the frequency f of the electric power monitoring signal behind the calculating sampling, and the position of definite match point, suppose this frequency f weekly the actual samples of ripple count and be N; Then confirm the position of N match point, wherein, N is a natural number, should be noted that; If fixed sample rate is 1kHz, expression is corresponding to the electric power monitoring signal of 50Hz, and to count be 20 points to the actual samples of ripple weekly; The implication of ripple is each cycle wave band weekly, and those skilled in the art should understand, and repeats no more at this.
Need to prove that the method for the frequency of the electric power monitoring signal among the said step S2 behind the calculating sampling comprises hardware approach and software approach.
Wherein, Said hardware approach is specially: through the electric power monitoring signal after the sampling is carried out the shaping conversion; CPU detects the frequency that shaped pulse comes the electric power monitoring signal behind the calculating sampling at interval through timer; This hardware approach is subject to hardware resource to a certain extent, and those skilled in the art should understand, and repeats no more at this.
Said software approach is specially: through the frequency of the electric power monitoring signal behind the time interval at the zero point calculating sampling of the electric power monitoring signal after the sampling; It is to be noted; This software approach has agile and all-purpose characteristics, but the arithmetic capability of CPU is required to repeat no more at this than higher.
Please combine to consult Fig. 2, Fig. 2 is a particular flow sheet of confirming the position of match point among the step S2 according to the invention, and as shown in Figure 2, this method specifically may further comprise the steps:
In step S21, confirm the position of actual samples point, suppose that the SI corresponding to said fixed sample rate is 1/ (f0*N), then the position of actual samples point is Y [n0]=n0/ (f0*N), n0=0; 1,2 ..., N, N+1;, wherein, N is a standard ripple sampling number weekly, in this scheme; Standard weekly ripple sampling number and said frequencies f weekly the actual samples of ripple count and should be consistent, in the present embodiment, N is 128, f0 is a standard power monitor signal frequency; Generally speaking, f0 is 50Hz.
In step S22, confirm the position of match point to suppose that the SI corresponding to said frequency f is 1/ (f*N) that then the position of match point is X [n]=n/ (f*N) according to frequency f, wherein, and n=0,1,2 ..., N.
In step S3, calculate the numerical value of N match point.
Please combine to consult Fig. 3, Fig. 3 is the particular flow sheet of step S3 of the present invention, and is as shown in Figure 3, and said step S3 specifically may further comprise the steps:
In step S31, be in two adjacent somes calculating linear scaling constant k of position Y [n0] of actual samples point according to the position X [n] of said match point;
In step S32, according to the numerical value of linear scaling constant k with N the match point of neighbouring sample value The Fitting Calculation of reality.
For example, during n=3, at first, calculate X [3] value; The size of supposing X [3] value is between the value of position Y [3] and Y [4] of actual samples point, wherein, and n0=3; The position of the actual samples point that it is corresponding is Y [3], likewise, and n0=4; The position of the actual samples point that it is corresponding is Y [4], i.e. Y [3] ≤X [3] ≤Y [4], then linear scaling constant k=(X [3]-Y [3])/(Y [4]-Y [3]).
Then; Utilize YA [3]+(YA [4]-YA [3]) * k to be used as the match value XA [3] of DFT computing; Wherein, YA [3] and YA [4] are two actual adjacent sampled point numerical value, should be noted that; YA [3] and YA [4] they are the values that obtains through the A/D converter sampling. those skilled in the art should understand, and repeats no more at this.
What deserves to be mentioned is,, under the situation that computational accuracy meets the demands, also availablely be used as match value near the actual samples point value of match point if fixed sample rate is enough high.For example, use as XA [3] with YA [3], at this moment, XA [3] difference of YA [3] and The Fitting Calculation is very little on the one hand, and on the other hand, last result of calculation must meet design requirement, and repeats no more at this.
In step S4, the numerical applications of a said N match point is carried out various fundamental operations in the DFT algorithm.Said various fundamental operation comprises real part, imaginary part, amplitude and the phase place of calculating electric parameter; Wherein, said electric parameter comprises analog voltage signal and analog current signal.
See also Fig. 4, Fig. 4 is the structural representation of electric power monitoring signals sampling device of the present invention, and is as shown in Figure 4, and said device comprises successively the sampling unit 100 that connects, confirms unit 200, computing unit 300 and DFT algorithm unit 400; Wherein:
Sampling unit 100 is used to receive the electric power monitoring signal, and adopts fixed sample rate that said electric power monitoring signal is sampled;
Confirm unit 200, be used for the frequency f of the electric power monitoring signal behind the calculating sampling, and the position of definite match point, suppose this frequency f weekly the actual samples of ripple count and be N, then confirm the position of N match point, wherein, N is a natural number;
DFT algorithm unit 400 is used for the numerical applications of a said N match point is carried out various fundamental operations in the DFT algorithm.
Compared to prior art; Under the condition of fixed sample rate; But produce the sampled data of periodic extension through the mode of match sampled point; And this sampled data is used for the DFT algorithm, this technical scheme is compared with the variable sampling rate DFT algorithm under fixedly computing is counted, and has more ubiquity and applicability.
The above is merely the preferred embodiments of the present invention, is not limited to the present invention, and for a person skilled in the art, the present invention can have various changes and variation.All within spirit of the present invention and principle, any modification of being done, be equal to replacement, improvement etc., all should be included within the claim scope of the present invention.
Claims (10)
1. an electric power monitoring signals sampling method is characterized in that, said method comprising the steps of:
S1. receive the electric power monitoring signal, and adopt fixed sample rate that said electric power monitoring signal is sampled;
S2. the frequency f of the electric power monitoring signal behind the calculating sampling, and the position of definite match point, suppose this frequency f weekly the actual samples of ripple count and be N, then confirm the position of N match point, wherein, N is a natural number;
S3. calculate the numerical value of N match point.
2. method according to claim 1 is characterized in that, and is further comprising the steps of after the said step S3:
S4. the numerical applications of a said N match point is carried out various fundamental operations in the DFT algorithm.
3. method according to claim 2 is characterized in that, said various fundamental operations comprise real part, imaginary part, amplitude and the phase place of calculating electric parameter; Wherein, said electric parameter comprises analog voltage signal and analog current signal.
4. method according to claim 1 is characterized in that, the method for the frequency of the electric power monitoring signal among the said step S2 behind the calculating sampling comprises hardware approach and software approach.
5. method according to claim 4; It is characterized in that; Said hardware approach is specially: through the electric power monitoring signal after the sampling is carried out the shaping conversion, CPU detects the frequency that shaped pulse comes the electric power monitoring signal behind the calculating sampling at interval through timer.
6. method according to claim 4 is characterized in that, said software approach is specially: through the frequency of the electric power monitoring signal behind the time interval at the zero point calculating sampling of the electric power monitoring signal after the sampling.
7. method according to claim 1 is characterized in that, confirms among the said step S2 that the position of match point specifically may further comprise the steps:
S21. confirm the position of actual samples point, suppose that the SI corresponding to said fixed sample rate is 1/ (f0*N), then the position of actual samples point is Y [n0]=n0/ (f0*N), n0=0; 1,2 ... N, N+1 ... Wherein, N is a standard ripple sampling number weekly, and f0 is a standard power monitor signal frequency;
S22. confirm the position of match point according to frequency f, suppose that the SI corresponding to said frequency f is 1/ (f*N), then the position of match point is X [n]=n/ (f*N), wherein, n=0,1,2 ..., N.
8. method according to claim 7 is characterized in that, said step S3 specifically may further comprise the steps:
S31. calculate the linear scaling constant k according to the position X [n] of said match point and two adjacent points of position Y [n0] of being in actual samples point;
S32. according to the numerical value of linear scaling constant k with N the match point of neighbouring sample value The Fitting Calculation of reality.
9. the sampling apparatus of an electric power signal is characterized in that, said device comprises successively the sampling unit that connects, confirms unit and computing unit; Wherein:
Sampling unit is used to receive the electric power monitoring signal, and adopts fixed sample rate that said electric power monitoring signal is sampled;
Confirm the unit, be used for the frequency f of the electric power monitoring signal behind the calculating sampling, and the position of definite match point, suppose this frequency f weekly the actual samples of ripple count and be N, then confirm the position of N match point, wherein, N is a natural number;
Computing unit is used to calculate the numerical value of N match point.
10. device according to claim 9 is characterized in that, said device also comprises the DFT algorithm unit that is used for the numerical applications of a said N match point is carried out in the DFT algorithm various fundamental operations that is connected with said computing unit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012102792190A CN102809679A (en) | 2012-08-08 | 2012-08-08 | Method and device for sampling electric monitoring signal |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012102792190A CN102809679A (en) | 2012-08-08 | 2012-08-08 | Method and device for sampling electric monitoring signal |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN102809679A true CN102809679A (en) | 2012-12-05 |
Family
ID=47233437
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2012102792190A Pending CN102809679A (en) | 2012-08-08 | 2012-08-08 | Method and device for sampling electric monitoring signal |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102809679A (en) |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0456132A2 (en) * | 1990-05-08 | 1991-11-13 | Kabushiki Kaisha Toshiba | System for determining an alternating voltage and/or current |
| JPH10170558A (en) * | 1996-12-16 | 1998-06-26 | Matsushita Electric Ind Co Ltd | Ac signal measuring device |
| CN101216511A (en) * | 2008-01-18 | 2008-07-09 | 杭州万工科技有限公司 | Digital synchronous sampling method |
| CN101299657A (en) * | 2008-06-26 | 2008-11-05 | 上海交通大学 | Symbol timing synchronizing apparatus for complete digital receiver |
| CN201191306Y (en) * | 2008-04-25 | 2009-02-04 | 四川启明星蜀达电气有限公司 | High precision electrical energy meter adopting frequency tracking sampling circuit |
| CN101655519A (en) * | 2009-09-14 | 2010-02-24 | 国电南京自动化股份有限公司 | Data processing method for alternating current sampling of digital transformer station measurement and control device |
| CN101806832A (en) * | 2010-04-15 | 2010-08-18 | 南京邮电大学 | Measuring method for frequencies of low-frequency signals |
| CN102435844A (en) * | 2011-11-01 | 2012-05-02 | 南京磐能电力科技股份有限公司 | Sinusoidal signal phasor calculating method being independent of frequency |
| CN102520245A (en) * | 2011-09-28 | 2012-06-27 | 天津大学 | Micro-grid harmonic and inter-harmonic analysis method based on cubic spline interpolation waveform reconstruction |
-
2012
- 2012-08-08 CN CN2012102792190A patent/CN102809679A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0456132A2 (en) * | 1990-05-08 | 1991-11-13 | Kabushiki Kaisha Toshiba | System for determining an alternating voltage and/or current |
| JPH10170558A (en) * | 1996-12-16 | 1998-06-26 | Matsushita Electric Ind Co Ltd | Ac signal measuring device |
| CN101216511A (en) * | 2008-01-18 | 2008-07-09 | 杭州万工科技有限公司 | Digital synchronous sampling method |
| CN201191306Y (en) * | 2008-04-25 | 2009-02-04 | 四川启明星蜀达电气有限公司 | High precision electrical energy meter adopting frequency tracking sampling circuit |
| CN101299657A (en) * | 2008-06-26 | 2008-11-05 | 上海交通大学 | Symbol timing synchronizing apparatus for complete digital receiver |
| CN101655519A (en) * | 2009-09-14 | 2010-02-24 | 国电南京自动化股份有限公司 | Data processing method for alternating current sampling of digital transformer station measurement and control device |
| CN101806832A (en) * | 2010-04-15 | 2010-08-18 | 南京邮电大学 | Measuring method for frequencies of low-frequency signals |
| CN102520245A (en) * | 2011-09-28 | 2012-06-27 | 天津大学 | Micro-grid harmonic and inter-harmonic analysis method based on cubic spline interpolation waveform reconstruction |
| CN102435844A (en) * | 2011-11-01 | 2012-05-02 | 南京磐能电力科技股份有限公司 | Sinusoidal signal phasor calculating method being independent of frequency |
Non-Patent Citations (2)
| Title |
|---|
| 蒋雷海等: "数字化保护采样数据处理方案", 《电力系统自动化》, vol. 34, no. 17, 10 September 2010 (2010-09-10), pages 42 - 44 * |
| 郭乐等: "插值算法在智能变电站中的应用", 《电力自动化设备》, vol. 30, no. 10, 31 October 2010 (2010-10-31) * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR20100007445A (en) | Apparatus for noise gating from partial discharge and detecting partial discharge area of powr equipment | |
| CN102128982A (en) | Harmonic analysis method based on windowed interpolation FFT (Fast Fourier Transform) base frequency tracking technology | |
| CN114252837B (en) | High-precision equal sampling system and method for harmonic measurement of digital power meter | |
| CN102809687B (en) | Digital measurement method for alternating-current frequency | |
| CN103969508A (en) | Real-time high-precision power harmonic analysis method and device | |
| CN103913633A (en) | High-spectrum-resolution phase spectrum measuring device and method based on multi-frequency sinusoidal signals | |
| CN103926462A (en) | Rapid harmonic wave analyzing method and device of power system | |
| CN103995183A (en) | Method for detecting continuity of wiring impedance of PCB based on rapid pulse response | |
| US8680842B2 (en) | Method for measurement of total harmonic distortion | |
| CN106154034B (en) | A kind of harmonic measuring device and method of power module | |
| CN113064021A (en) | Measurement and control device and method for realizing high-order harmonic suppression of power electronic grid | |
| CN101937017A (en) | Dynamic direct-current removing method for intelligent electric meter during alternating-current sampling | |
| RU2435168C1 (en) | Method for harmonic analysis of periodic multifrequency signal | |
| KR101524204B1 (en) | High throughput semiconductor device testing | |
| CN103575979A (en) | Method for digital measuring of alternating current frequency | |
| KR102193912B1 (en) | Partial discharging signal detector of power equipments and method thereof | |
| CN106612084A (en) | Current sampling processing circuit and current sampling processing method | |
| CN102809679A (en) | Method and device for sampling electric monitoring signal | |
| CN104483563B (en) | The synchronous sampling method of electric power signal and system | |
| CN104483545B (en) | The harmonic measuring method and system of power system | |
| CN102103163B (en) | Method for measuring arbitrary waveform estimated based on synchronous lock phase and half-wave | |
| CN104849551B (en) | A kind of humorous phase angle analysis method | |
| CN113608023A (en) | Sampling frequency self-adaptive harmonic detection method and system | |
| CN115825941A (en) | Frequency modulation continuous wave radar device and signal processing method thereof | |
| CN103744063B (en) | A kind of portable aiming formula radar interference simulator |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C12 | Rejection of a patent application after its publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20121205 |