CN101577175A - Electronic current transformer signal reduction method based on Rogowski coil - Google Patents
Electronic current transformer signal reduction method based on Rogowski coil Download PDFInfo
- Publication number
- CN101577175A CN101577175A CNA2009100262450A CN200910026245A CN101577175A CN 101577175 A CN101577175 A CN 101577175A CN A2009100262450 A CNA2009100262450 A CN A2009100262450A CN 200910026245 A CN200910026245 A CN 200910026245A CN 101577175 A CN101577175 A CN 101577175A
- Authority
- CN
- China
- Prior art keywords
- integration
- component
- electronic current
- formula
- data
- 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
Images
Abstract
The invention discloses an electronic current transformer signal reduction method based on a Rogowski coil, which is characterized in that: the method comprises the following steps: 1) performing digital integration on signals on the secondary side of an electronic current transformer to obtain an integral output value; 2) calculating a system frequency f according to data y after integration by a zero crossing algorithm; 3) calculating a direct current component z1 of data y(i) after the integration according to the calculated system frequency f by a summation algorithm; 4) obtaining a direct current component z2 of data x(i) before the integration according to the change rate of the direct current component z1 before the integration; and 5) filtering a direct current component z2 in an integration algorithm, and filtering the direct current z1 after the integration by a point-wise attenuation method in the process of digital integration to obtain a final integral output value. The electronic current transformer signal reduction method can filter the direct current components before and after the integration so as to improve the integral accuracy, avoid the angular deviation problem in a lossy integration algorithm, and improve the steady state and transient state indexes of devices.
Description
Technical field
The present invention relates to a kind of method that the current differential signal of sieve Koffsky coil output in the electronic mutual inductor system is reduced, belong to technical field of power systems.
Background technology
Along with the expansion of scale of power, phenomenons such as the intrinsic CT of regional traditional electromagnetic transformer is saturated, ferro resonance are serious all the more, need to adopt novel instrument transformer solve these problems.Meanwhile, along with semiconductor technology, computer technology, development of Communication Technique, the research and the application of active formula electronic mutual inductor make great progress, and have been in pilot in the China Power system and have used to the stage of popularizing transition in an all-round way.In the active formula electronic current mutual inductor system, adopt sieve Koffsky coil, have no magnetic saturation, transient characterisitics are good, precision is high characteristics as current sense device.But the output of sieve Koffsky coil secondary side is the differential signal of electric current, need by integrator it be reduced in follow-up link.Adopt the hardware Integral Technology, can be because the discreteness problem of device be brought very big error to integral result.The software integration method of existing analog hardware scheme also can will be exported bigger DC component even integral process is not restrained owing to the continuous number integration.
Summary of the invention
Technical problem to be solved by this invention provides a kind of precision height, dispersion is little, hardware investment the is few electronic current mutual inductor signal reduction method based on sieve Koffsky coil.
In electronic current mutual inductor signal reduction process based on sieve Koffsky coil, the difficult problem of integral algorithm maximum is exactly how to eliminate the influence of DC component, conventional method adopts the mode that diminishes integration to eliminate the influence of DC component, detect data frequency behind the integration among the present invention at first in real time, then according to the frequency that records, calculate the DC component z behind the integration
1, and then pass through z
1Rate of change extrapolate DC component z before the integral element
2, give filtering at integral algorithm; For z
1, in the digital integration process, adopt the in addition filtering of method of pointwise decay.
For solving the problems of the technologies described above, the invention provides a kind of electronic current mutual inductor signal reduction method based on sieve Koffsky coil, it is characterized in that: may further comprise the steps:
1) utilizes formula (1) that electronic current mutual inductor secondary side current signal is carried out digital integration, draw the integration output valve;
Y (i)=y (i-1)+x (i)-z
2-α * z
1Formula (1)
X in the formula (i) is the input of integral algorithm, and y (i) is output, and f is a system frequency, f
sBe sample frequency, z
1Be DC component behind the integration, z
2Be DC component before the integration, α is an attenuation coefficient.
In the formula, z
1, z
2Initial value be made as 0.α decides according to the actual conditions of voltage class of electric power system or capacity, generally is made as 0.5 second to 2 seconds damped cycle, is assumed to be t (unit is second), and then attenuation coefficient is
α=1/ (t*f
s) formula (2)
2) adopted mean algorithm, calculated system frequency f according to data y behind the integration;
Adopt behind the integration data computation frequency to be because: the primary current signal is through after sieve Koffsky coil, and high fdrequency component is exaggerated, and can the precision of frequency computation part be exerted an influence.
3) computational process adopts the summation algorithm that adds up, according to the system frequency f that calculates, and the DC component z of data (y (i)) behind the calculating integration
1
4) according to the z that calculates
1With original z
1Backup z '
1Between rate of change, obtain data (x before the integration
(i)) DC component z
2
5) filtering DC component z in integral algorithm
2, DC component z behind the method filtering integration of employing pointwise decay in the digital integration process
1, draw final integration output valve.
Among the present invention, the software integral Calculation cycle is identical with the sampling period, i.e. f
sInverse.
The beneficial effect that the present invention reached:
Of the present invention based on sieve Koffsky coil electronic current mutual inductor signal reduction method, before can the filtering integration and the DC component behind the integration, thereby improved integral accuracy, avoided diminishing the angular deflection problem in the integral algorithm, realize harmless completely integration, promoted the stable state index and the transient state index of device.
In addition, this method does not need additionally to increase electronic loop, directly finishes in the data processing module of the merge cells of electronic mutual inductor, thereby has reduced the cost of system.The hardware integral algorithm comprises resistance, electric capacity, and the precision of integration is subjected to the influence of device dispersion, and this method is realized by software fully, avoided the influence of device dispersion.
Description of drawings
Fig. 1 is the flow chart that calculates the DC component process in this method.
Embodiment
The invention provides a kind of electronic current mutual inductor signal reduction method, it is characterized in that: may further comprise the steps based on sieve Koffsky coil:
1) utilizes formula (1) that electronic current mutual inductor secondary side signal is carried out digital integration, draw the integration output valve;
Y (i)=y (i-1)+x (i)-z
2-α * z
1Formula (1)
In the formula, z
1, z
2Initial value be made as 0.α decides according to the actual conditions of voltage class of electric power system or capacity, generally is made as 0.5 second to 2 seconds damped cycle, is assumed to be t (unit is second), and then attenuation coefficient is
α=1/ (t*f
s) formula (2)
2) adopt zero crossing algorithm, calculate system frequency f according to data y behind the integration.Suppose that first positive zero crossing occurs in M and M+1 constantly, i.e. y (M)＜0, y (M+1)＞0, next positive zero crossing occur in N and N+1 constantly, i.e. y (N)＜0, and y (N+1)＞0, then the frequency computation part formula is:
f＝1/(N-M+|y(N)|/(y(N+1)+|y(N)|)-|y(M)|/(y(M+1)+|y(M)|))
Formula (3)
The data computation frequency is because after primary current signal process sieve Koffsky coil, high fdrequency component is exaggerated, and can the precision of frequency computation part be exerted an influence behind the employing integration.
3) computational process adopts the summation algorithm that adds up, according to the system frequency f that calculates, and the DC component z of data (y (i)) behind the calculating integration
1:
Formula (4)
z
1Upgrade z originally
1Backup is z '
1
4) according to z
1Rate of change, obtain data (x before the integration
(i)) DC component z
2:
z
2=f* (z
1-z '
1) formula (5)
5) filtering DC component z in integral algorithm
2, DC component z behind the method filtering integration of employing pointwise decay in the digital integration process
1, be presented as " the α * z in the formula (1)
1", draw final integration output valve.
More than various in x (i) be the input of integral algorithm, y (i) is for exporting, f is a system frequency, f
sBe sample frequency, z
1Be DC component behind the integration, z
2Be DC component before the integration, α is an attenuation coefficient.
In this programme, the software integral Calculation cycle is the same with the sampling period, i.e. f
sInverse.
In addition, this method can be carried out switching flexibly by configuration words.The configuration menu of merge cells has " whether adopting the software integration " configuration, if be set to drop into, output be integration data, if be set to withdraw from, output be initial data.
The present invention is illustrated according to the preferred embodiment, should be appreciated that the foregoing description does not limit the present invention in any form, and all employings are equal to the technical scheme that form obtained of replacement or equivalent transformation, all drop within protection scope of the present invention.
Claims (5)
1. electronic current mutual inductor signal reduction method based on sieve Koffsky coil is characterized in that may further comprise the steps:
1) utilizes formula (1) that electronic current mutual inductor secondary side signal is carried out digital integration, draw the integration output valve;
y(i)＝y(i-1)+x(i)-z
2-α*z
1 (1)
2) adopt zero crossing algorithm, calculate system frequency f according to data y behind the integration;
3) adopt the summation algorithm that adds up, according to the DC component z of data (y (i)) behind the system frequency f calculating integration that calculates
1
4) according to the z that calculates
1With original z
1Backup z '
1Between rate of change, obtain data (x before the integration
(i)) DC component z
2
5) filtering DC component z in integral algorithm
2, DC component z behind the method filtering integration of employing pointwise decay in the digital integration process
1, draw final integration output valve.
2. the electronic current mutual inductor signal reduction method based on sieve Koffsky coil according to claim 1, it is characterized in that: in described step 2) in, utilize formula (3) computing system frequency f, f=1/ (N-M+|y (N) |/(y (N+1)+| y (N) |)-| y (M) |/(y (M+1)+| y (M) |)) formula (3).
3. the electronic current mutual inductor signal reduction method based on sieve Koffsky coil according to claim 1 and 2 is characterized in that: in described step 3), utilize formula (4) to calculate data (y (i)) DC component z behind the integration
1,
Formula (4).
4. the electronic current mutual inductor signal reduction method based on sieve Koffsky coil according to claim 1 and 2 is characterized in that: in described step 4), utilize formula (5) to calculate the DC component z of the preceding data (y (i)) of integration
2,
z
2=f* (z
1-z '
1) formula (5).
5. the electronic current mutual inductor signal reduction method based on sieve Koffsky coil according to claim 3 is characterized in that: in described step 4), utilize formula (5) to calculate preceding data (y (i)) the DC component z of integration
2,
z
2=f* (z
1-z '
1) formula (5).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200910026245A CN101577175B (en) | 2009-03-26 | 2009-03-26 | Electronic current transformer signal reduction method based on Rogowski coil |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200910026245A CN101577175B (en) | 2009-03-26 | 2009-03-26 | Electronic current transformer signal reduction method based on Rogowski coil |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101577175A true CN101577175A (en) | 2009-11-11 |
| CN101577175B CN101577175B (en) | 2012-09-26 |
Family
ID=41272072
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN200910026245A Active CN101577175B (en) | 2009-03-26 | 2009-03-26 | Electronic current transformer signal reduction method based on Rogowski coil |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101577175B (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104483542A (en) * | 2014-12-29 | 2015-04-01 | 威胜集团有限公司 | Rogowski-coil-based electric energy metering method |
| CN110619175A (en) * | 2019-09-17 | 2019-12-27 | 贵州电网有限责任公司 | Dynamic attenuation integral reduction method for acquisition unit of electronic transformer |
| CN111426881A (en) * | 2020-05-13 | 2020-07-17 | 常熟瑞特电气股份有限公司 | RIM type insulation monitoring method and device |
| CN115078820A (en) * | 2022-08-19 | 2022-09-20 | 石家庄科林电气股份有限公司 | Saturation processing method for protection current transformer of low-voltage intelligent circuit breaker |
-
2009
- 2009-03-26 CN CN200910026245A patent/CN101577175B/en active Active
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104483542A (en) * | 2014-12-29 | 2015-04-01 | 威胜集团有限公司 | Rogowski-coil-based electric energy metering method |
| CN110619175A (en) * | 2019-09-17 | 2019-12-27 | 贵州电网有限责任公司 | Dynamic attenuation integral reduction method for acquisition unit of electronic transformer |
| CN111426881A (en) * | 2020-05-13 | 2020-07-17 | 常熟瑞特电气股份有限公司 | RIM type insulation monitoring method and device |
| CN115078820A (en) * | 2022-08-19 | 2022-09-20 | 石家庄科林电气股份有限公司 | Saturation processing method for protection current transformer of low-voltage intelligent circuit breaker |
| CN115078820B (en) * | 2022-08-19 | 2022-11-18 | 石家庄科林电气股份有限公司 | Saturation processing method for protection current transformer of low-voltage intelligent circuit breaker |
Also Published As
| Publication number | Publication date |
|---|---|
| CN101577175B (en) | 2012-09-26 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US20140118003A1 (en) | Fault diagnosis and preliminary location system and method for transformer core looseness | |
| CN101577175B (en) | Electronic current transformer signal reduction method based on Rogowski coil | |
| CN108037475B (en) | Harmonic transfer characteristic test system for capacitor voltage transformer | |
| CN103078640B (en) | A kind of RLS adaptive-filtering calibration steps for ADC | |
| CN105137757A (en) | Repeated controller with frequency adaptive capability, and control method | |
| CN106093547A (en) | Rogowski coil current transformer measuring device and method based on auxiliary coil correction | |
| CN102435849A (en) | Method for improving frequency measurement precision by using digital filter | |
| CN106484962B (en) | A kind of symbolic analysis method of resonance type wireless transmission system steady-state characteristic | |
| CN112068064A (en) | Running three-phase voltage transformer error calculation method with background influence quantity deducted | |
| CN103884931A (en) | Testing and recording device for load characteristics of transformer substation bus | |
| CN110300932A (en) | The design method of the filter of delay compensator and feedback, the control device of electric motor for using it | |
| CN204439713U (en) | Based on the hollow coil current transformer of Novel DC isolation integrator | |
| CN113162002A (en) | Direct current traveling wave protection method and system considering broadband measurement link | |
| CN111679239B (en) | Voltage transformer verification system and method for flexible direct current power grid | |
| CN111505375A (en) | Frequency measurement method and device | |
| CN108627793B (en) | Electronic current transformer fault identification method based on waveform inversion | |
| Aleixo et al. | Micro‐PMU based on Savitzky–Golay filter | |
| CN101477143A (en) | Electronic current mutual inductor data processing method based on multi-sensor data amalgamation technology | |
| Wang et al. | Effects of control voltage saturation and sensor noise on the resistive wall mode feedback in ITER | |
| CN104267230A (en) | Signal recovery method for passive electronic type voltage transformer | |
| CN105957703B (en) | The digital integration method and digital integrator of electronic mutual inductor | |
| CN203368437U (en) | Real-time integrator drifting compensation alternation-type integrator | |
| Qiu et al. | Design of A Hybrid Compression Algorithm for High-fidelity Synchro-waveform Measurements | |
| CN108919163A (en) | Electronic current mutual inductor harmonic wave and frequency aliasing characteristic test system and its model | |
| CN110780099B (en) | Method for improving influence of self-heating of electric energy meter on performance of mutual inductor and electric energy meter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |