CN101980416A - Method for realizing sampling value synchronization in intelligent substation system - Google Patents
Method for realizing sampling value synchronization in intelligent substation system Download PDFInfo
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- CN101980416A CN101980416A CN2010105103947A CN201010510394A CN101980416A CN 101980416 A CN101980416 A CN 101980416A CN 2010105103947 A CN2010105103947 A CN 2010105103947A CN 201010510394 A CN201010510394 A CN 201010510394A CN 101980416 A CN101980416 A CN 101980416A
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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
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
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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
- Y04S10/00—Systems supporting electrical power generation, transmission or distribution
- Y04S10/16—Electric power substations
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Abstract
The invention provides a method for realizing sampling value synchronization in an intelligent substation system, which comprises the following steps of: a, monitoring the receiving time of each datum by a protecting device in real time; b, deducing the sampling time of each merging unit with a phase locked loop algorithm; and c, obtaining the information of the sampling time corresponding to the protecting device clock by a linear interpolation algorithm, and realizing the synchronization of the protective device with each sampling value of the merging unit. The invention tracks the receiving time of each datum by using an FPGA (Field Programmable Gate Array) chip, and then deduces the sampling time of each sampling device with the PLL (Phase Locked Loop) algorithm, and further obtains the information of the sampling time corresponding to a receiving device clock by an interpolation or fitting algorithm, thereby realizing the synchronization of the data. The method is performed by hardware, has high precision and strong real-time property, saves the software workload of a secondary device and increases the work efficiency of the secondary device; moreover, the configuration is flexible, the output of data of different sampling rates can be realized, and the reliability of the system is improved.
Description
Technical field
The present invention relates to the intelligent substation technical field, relate in particular to and realize the synchronous method of sampled value in a kind of intelligent substation system.
Background technology
Along with semiconductor technology, computer technology, development of Communication Technique, comprise that electronic mutual inductor, fiber optic Ethernet network, 100 m switch technology have all obtained using widely in transformer station.Simultaneously, the proposition of intelligent grid notion also requires transformer station must realize intellectuality as early as possible, thereby improves reliability, the economic index of network system.Intelligent substation is compared with traditional transformer station, and electric parameters such as voltage, electric current samplings changes into distributedly from centralized, promptly samples and is finished by the different location that the is distributed to transformer station different device of (at interval) (merge cells, i.e. MU).Because the system clock difference of each device causes sampling instant there are differences, therefore need carry out Synchronous Processing and could satisfy the requirement of striding interval equipment.
Existing way is, sets up the sample-synchronous net in transformer station, insert this network except each sampling apparatus, also comprise a clock generator.Clock generator sends synchronizing signal at regular intervals, and each sampling apparatus receives behind this signal the system clock zero clearing with oneself, thereby realizes synchronously.But the shortcoming of this scheme is:
1) need set up independently Synchronization Network in transformer station, increase investment;
2) synchronous reliability is to be against each equipment and the communication link in the Synchronization Network, and arbitrary link is made mistakes and all can be caused equipment work unusual.
Summary of the invention
The object of the present invention is to provide and realize the synchronous method of sampled value in a kind of intelligent substation system.
The present invention is achieved by the following technical solutions:
Realize the synchronous method of sampled value in a kind of intelligent substation system, comprise step:
A: the time of reception of each data of protective device real time monitoring;
B: adopt phase-lock-loop algorithm to know the sampling instant of each merge cells by inference;
C: obtain the information of the sampling instant corresponding by linear interpolation algorithm, realize the synchronous of protective device and each sampled value of merge cells with the protective device clock.
Wherein, the field programmable gate array unit by protective device inside carries out data monitoring among the step a.
Wherein, phase-lock-loop algorithm specifically comprises step described in the step b:
S1: the field programmable gate array chip real time monitoring Ethernet message of protective device inside arrives constantly, protective device as required, the size of set algorithm data window;
S2: the time of reception of protective device tracking data, draw the deviation and the variation tendency thereof of MU system clock and protective device system clock, as the foundation of data interpolating algorithm;
S3: data are carried out interpolation obtain synchrodata.
Wherein, when adopting phase-lock-loop algorithm among the step b, protective device is put the synchronization loss sign, the correlation function of locking simultaneously.
Wherein, linear interpolation algorithm described in the step c is specially by the approximate actual waveform that replaces of the straight line of original sample point; The unit impact response of linear interpolation is seen following formula:
Wherein, described protective device is a data sink.
Wherein, described merge cells is the distributed sample device.
The embodiment of the invention compared with prior art, beneficial effect is: the present invention adopts field programmable gate array (FPGA) chip to follow the tracks of the time of reception of each data, adopt phase-locked loop (PLL) algorithm to know the sampling instant of each sampling apparatus by inference again, and then by interpolation or fit the information that algorithm obtains the sampling instant corresponding with the receiving system clock, thereby realize each data synchronization.The present invention adopts hardware to implement precision height, real-time; Save the software work amount of secondary device, improve the operating efficiency of secondary device; Simultaneously, can flexible configuration, realize the output of different sample rate data; Improved the reliability of system.
Description of drawings
Fig. 1 is the inventive method flow chart;
Fig. 2 is an embodiment of the invention schematic diagram;
Fig. 3 is a linear interpolation schematic diagram of the present invention.
Embodiment
In order to make purpose of the present invention, technical scheme and advantage clearer,, the present invention is further elaborated below in conjunction with drawings and Examples.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 shown in Figure 1ly, the inventive method flow chart comprises:
Step 101: the time of reception of each data of protective device real time monitoring;
Step 102: adopt phase-lock-loop algorithm to know the sampling instant of each merge cells by inference;
Step 103: obtain the information of the sampling instant corresponding by linear interpolation algorithm, realize the synchronous of protective device and each sampled value of merge cells with the protective device clock.
Linear interpolation algorithm as shown in Figure 3, among the figure, [x0, y0], [x1, y1] are the crude sampling value, the geometric meaning of linear interpolation is exactly with the approximate actual waveform that replaces of the straight line by original sample point.The unit impact response of linear interpolation is seen following formula.
Linear interpolation algorithm is simple and easy to realize, can satisfies the application of intelligent substation system fully.
Wherein, protective device is a data sink; Merge cells is the distributed sample device.
Be further elaborated below in conjunction with specific embodiment, see also shown in Figure 2:
Be example with a merge cells (MU) among the figure.The system clock scale of supposing MU is 250 microseconds, i.e. per second 4000 points.The system clock scale of protective device is 833 microseconds, i.e. ripple (20ms) 24 point samplings weekly, and the phase-lock-loop algorithm main contents are as follows:
It is consistent with local No. 0 moment of counter of protective device to suppose that merge cells is gathered No. 0 moment of counter, but then theoretical calculate goes out arrival such as merge cells message cn0, cn1, cn2 to protect the moment of CPU be Tcn0, Tcn1, Tcn2 ...But because crystal oscillator difference, merge cells system clock and protective device system clock can progressively depart from, and cause step-out.
The present invention adopts phase-lock-loop algorithm to realize the data sync of protective device system clock and merge cells system clock, and step is divided into following a few step.
S1: the fpga chip real time monitoring Ethernet message of protective device inside arrives constantly, although the arrival of each packet constantly and between the interval have shake, this shake can be passed through the algorithm filtering.Protective device is the size of set algorithm data window as required, is generally 1 second;
S2: protective device follow the tracks of 1 second data the time of reception, draw the deviation and the variation tendency thereof of MU system clock and protective device system clock, as after the foundation of 1s data interpolating algorithm;
S3: data are carried out interpolation obtain synchrodata.
Phase-lock-loop algorithm can not reach synchronous effect for progressively following very soon in the starting stage of communication foundation or recovery, that is to say that synchronous foundation needs certain hour.In this process, protective device must be put the synchronization loss sign, the function of latch-up protection simultaneously.This process could be opened this partial function after finishing, setting up synchronously.
The above only is preferred embodiment of the present invention, not in order to restriction the present invention, all any modifications of being done within the spirit and principles in the present invention, is equal to and replaces and improvement etc., all should be included within protection scope of the present invention.
Claims (7)
1. realize the synchronous method of sampled value in an intelligent substation system, it is characterized in that, comprise step:
A: the time of reception of each data of protective device real time monitoring;
B: adopt phase-lock-loop algorithm to know the sampling instant of each merge cells by inference;
C: obtain the information of the sampling instant corresponding by linear interpolation algorithm, realize the synchronous of protective device and each sampled value of merge cells with the protective device clock.
2. realize the synchronous method of sampled value in the intelligent substation as claimed in claim 1 system, it is characterized in that the field programmable gate array unit by protective device inside among the step a carries out data monitoring.
3. realize the synchronous method of sampled value in the intelligent substation as claimed in claim 1 system, it is characterized in that phase-lock-loop algorithm described in the step b specifically comprises step:
S1: the field programmable gate array chip real time monitoring Ethernet message of protective device inside arrives constantly, protective device as required, the size of set algorithm data window;
S2: the time of reception of protective device tracking data, draw the deviation and the variation tendency thereof of MU system clock and protective device system clock, as the foundation of data interpolating algorithm;
S3: data are carried out interpolation obtain synchrodata.
4. realize the synchronous method of sampled value in the intelligent substation as claimed in claim 3 system, it is characterized in that when adopting phase-lock-loop algorithm among the step b, protective device is put the synchronization loss sign, the correlation function of locking simultaneously.
5. realize the synchronous method of sampled value in the intelligent substation as claimed in claim 4 system, it is characterized in that linear interpolation algorithm described in the step c is specially by the approximate actual waveform that replaces of the straight line of original sample point; The unit impact response of linear interpolation is seen following formula:
6. realize the synchronous method of sampled value in the intelligent substation as claimed in claim 1 system, it is characterized in that described protective device is a data sink.
7. realize the synchronous method of sampled value in the intelligent substation as claimed in claim 1 system, it is characterized in that described merge cells is the distributed sample device.
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Cited By (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102539975A (en) * | 2012-01-12 | 2012-07-04 | 华南理工大学 | Method for carrying out synchronous on-line detection on data of 10kV merging units (MUs) based on voltage-phase comparison |
| CN102638323A (en) * | 2012-03-27 | 2012-08-15 | 许继集团有限公司 | Self-adaption data synchronizing method based on clock source |
| CN102761099A (en) * | 2011-04-29 | 2012-10-31 | 田立志 | Protection device with synchronization function in digital substation and synchronization method |
| CN103345543A (en) * | 2013-06-08 | 2013-10-09 | 广东电网公司电力科学研究院 | Intelligent substation merging unit simulation modeling method |
| CN103368681A (en) * | 2012-03-27 | 2013-10-23 | 湖南大学 | Substation SAV message estimation algorithm based on Lagrange interpolation |
| CN103487651A (en) * | 2013-09-24 | 2014-01-01 | 国家电网公司 | Sampled data processing method of APF controller based on FPGA and DSP |
| CN103763085A (en) * | 2014-01-17 | 2014-04-30 | 南京信息职业技术学院 | Method and device for high-speed collection and merging of multi-path data |
| CN103901292A (en) * | 2013-12-04 | 2014-07-02 | 国家电网公司 | Data sampling interpolation method |
| CN103969500A (en) * | 2014-04-11 | 2014-08-06 | 深圳市中电电力技术股份有限公司 | Device, method and system for collecting smart power grid analog quantity |
| CN104202139A (en) * | 2014-09-18 | 2014-12-10 | 国家电网公司 | System, device and method for realizing synchronization of sampling value serial numbers |
| CN104391674A (en) * | 2014-10-22 | 2015-03-04 | 积成电子股份有限公司 | Sampling value linear interpolation calculation device based on FPGA (Field Programmable Gate Array) and calculation method |
| CN104600678A (en) * | 2014-08-11 | 2015-05-06 | 长园深瑞继保自动化有限公司 | Bus protection current synchronization method |
| CN105376115A (en) * | 2015-12-01 | 2016-03-02 | 北京博维亚讯技术有限公司 | Hardware-based sampling value clock transparent transmission device and method for mutual inductor of transformer substation |
| CN106207989A (en) * | 2016-07-08 | 2016-12-07 | 山东鲁能智能技术有限公司 | Regional power grid based on alternating voltage zero-crossing point protection data interpolating synchronous method, system |
| CN107181583A (en) * | 2017-04-25 | 2017-09-19 | 国电南瑞科技股份有限公司 | The method that sampling value synchronization is realized based on Sampling interrupt event |
| CN107395306A (en) * | 2017-07-06 | 2017-11-24 | 中国南方电网有限责任公司 | A kind of network samples data syn-chronization method of discrimination based on temporal quality |
| CN109709422A (en) * | 2018-12-27 | 2019-05-03 | 中国南方电网有限责任公司 | A kind of removing method and its device of clock drift |
| CN109946513A (en) * | 2019-03-26 | 2019-06-28 | 江苏凌创电气自动化股份有限公司 | Based on across the gap digit change metering method of the absolute compensation of delay of network samples, apparatus and system |
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Cited By (27)
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| CN102761099B (en) * | 2011-04-29 | 2015-04-22 | 田立志 | Protection device with synchronization function in digital substation and synchronization method |
| CN102761099A (en) * | 2011-04-29 | 2012-10-31 | 田立志 | Protection device with synchronization function in digital substation and synchronization method |
| CN102539975A (en) * | 2012-01-12 | 2012-07-04 | 华南理工大学 | Method for carrying out synchronous on-line detection on data of 10kV merging units (MUs) based on voltage-phase comparison |
| CN102539975B (en) * | 2012-01-12 | 2014-07-02 | 华南理工大学 | Method for carrying out synchronous on-line detection on data of 10kV merging units (MUs) based on voltage-phase comparison |
| CN102638323A (en) * | 2012-03-27 | 2012-08-15 | 许继集团有限公司 | Self-adaption data synchronizing method based on clock source |
| CN103368681A (en) * | 2012-03-27 | 2013-10-23 | 湖南大学 | Substation SAV message estimation algorithm based on Lagrange interpolation |
| CN103345543A (en) * | 2013-06-08 | 2013-10-09 | 广东电网公司电力科学研究院 | Intelligent substation merging unit simulation modeling method |
| CN103487651A (en) * | 2013-09-24 | 2014-01-01 | 国家电网公司 | Sampled data processing method of APF controller based on FPGA and DSP |
| CN103901292A (en) * | 2013-12-04 | 2014-07-02 | 国家电网公司 | Data sampling interpolation method |
| CN103763085A (en) * | 2014-01-17 | 2014-04-30 | 南京信息职业技术学院 | Method and device for high-speed collection and merging of multi-path data |
| CN103763085B (en) * | 2014-01-17 | 2016-08-17 | 南京信息职业技术学院 | A kind of multichannel data high speed acquisition merges method and device |
| CN103969500B (en) * | 2014-04-11 | 2017-09-12 | 深圳市中电电力技术股份有限公司 | Intelligent grid analog acquisition device, method and system |
| CN103969500A (en) * | 2014-04-11 | 2014-08-06 | 深圳市中电电力技术股份有限公司 | Device, method and system for collecting smart power grid analog quantity |
| CN104600678A (en) * | 2014-08-11 | 2015-05-06 | 长园深瑞继保自动化有限公司 | Bus protection current synchronization method |
| CN104600678B (en) * | 2014-08-11 | 2018-03-13 | 长园深瑞继保自动化有限公司 | Bus protection current synchronization method |
| CN104202139A (en) * | 2014-09-18 | 2014-12-10 | 国家电网公司 | System, device and method for realizing synchronization of sampling value serial numbers |
| CN104391674A (en) * | 2014-10-22 | 2015-03-04 | 积成电子股份有限公司 | Sampling value linear interpolation calculation device based on FPGA (Field Programmable Gate Array) and calculation method |
| CN104391674B (en) * | 2014-10-22 | 2017-09-05 | 积成电子股份有限公司 | Sampled value linear interpolation arithmetic device and operation method based on FPGA |
| CN105376115A (en) * | 2015-12-01 | 2016-03-02 | 北京博维亚讯技术有限公司 | Hardware-based sampling value clock transparent transmission device and method for mutual inductor of transformer substation |
| CN106207989A (en) * | 2016-07-08 | 2016-12-07 | 山东鲁能智能技术有限公司 | Regional power grid based on alternating voltage zero-crossing point protection data interpolating synchronous method, system |
| CN106207989B (en) * | 2016-07-08 | 2018-07-24 | 山东鲁能智能技术有限公司 | Regional power grid protection data interpolating synchronous method based on alternating voltage zero-crossing point, system |
| CN107181583A (en) * | 2017-04-25 | 2017-09-19 | 国电南瑞科技股份有限公司 | The method that sampling value synchronization is realized based on Sampling interrupt event |
| CN107395306A (en) * | 2017-07-06 | 2017-11-24 | 中国南方电网有限责任公司 | A kind of network samples data syn-chronization method of discrimination based on temporal quality |
| CN107395306B (en) * | 2017-07-06 | 2019-06-21 | 中国南方电网有限责任公司 | A kind of network samples data synchronization method of discrimination based on temporal quality |
| CN109709422A (en) * | 2018-12-27 | 2019-05-03 | 中国南方电网有限责任公司 | A kind of removing method and its device of clock drift |
| CN109946513A (en) * | 2019-03-26 | 2019-06-28 | 江苏凌创电气自动化股份有限公司 | Based on across the gap digit change metering method of the absolute compensation of delay of network samples, apparatus and system |
| CN109946513B (en) * | 2019-03-26 | 2021-01-08 | 江苏凌创电气自动化股份有限公司 | Cross-interval digital metering method, device and system based on network sampling absolute delay compensation |
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Application publication date: 20110223 |