CN109283385A - A kind of arrester monitoring data on-line processing method and system - Google Patents

A kind of arrester monitoring data on-line processing method and system Download PDF

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Publication number
CN109283385A
CN109283385A CN201811210554.9A CN201811210554A CN109283385A CN 109283385 A CN109283385 A CN 109283385A CN 201811210554 A CN201811210554 A CN 201811210554A CN 109283385 A CN109283385 A CN 109283385A
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China
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current
signal
phase angle
phase
voltage
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CN201811210554.9A
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CN109283385B (en
Inventor
曾国辉
梁武民
兰五胜
和红伟
毛丽娜
路光辉
雍明超
周水斌
王伟杰
王青山
郭宏燕
陈磊
杨芳
李超
云亚文
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State Grid Corp of China SGCC
Xuji Group Co Ltd
XJ Electric Co Ltd
Xuchang XJ Software Technology Co Ltd
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State Grid Corp of China SGCC
Xuji Group Co Ltd
XJ Electric Co Ltd
Xuchang XJ Software Technology Co Ltd
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R19/00Arrangements for measuring currents or voltages or for indicating presence or sign thereof
    • G01R19/25Arrangements for measuring currents or voltages or for indicating presence or sign thereof using digital measurement techniques
    • G01R19/2506Arrangements for conditioning or analysing measured signals, e.g. for indicating peak values ; Details concerning sampling, digitizing or waveform capturing
    • G01R19/2509Details concerning sampling, digitizing or waveform capturing
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R23/00Arrangements for measuring frequencies; Arrangements for analysing frequency spectra
    • G01R23/02Arrangements for measuring frequency, e.g. pulse repetition rate; Arrangements for measuring period of current or voltage
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R23/00Arrangements for measuring frequencies; Arrangements for analysing frequency spectra
    • G01R23/16Spectrum analysis; Fourier analysis
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R25/00Arrangements for measuring phase angle between a voltage and a current or between voltages or currents
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R27/00Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
    • G01R27/02Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
    • G01R27/26Measuring inductance or capacitance; Measuring quality factor, e.g. by using the resonance method; Measuring loss factor; Measuring dielectric constants ; Measuring impedance or related variables
    • G01R27/2688Measuring quality factor or dielectric loss, e.g. loss angle, or power factor
    • G01R27/2694Measuring dielectric loss, e.g. loss angle, loss factor or power factor

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Mathematical Physics (AREA)
  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Testing Electric Properties And Detecting Electric Faults (AREA)

Abstract

The present invention relates to a kind of arrester monitoring data on-line processing method and systems, initial phase angle is found out by carrying out whole wave Fourier transformation to current acquisition unit and the collected signal of voltage acquisition unit, initial phase angle is modified according to the variation of power frequency, then least square method fitting a straight line is utilized, acquire the final initial phase angle and frequency of each phase current signal and each associated bus voltage signal, eliminate the cyclically-varying of the phase angle generation of electric current and voltage, it is poor to solve interference existing for existing arrester online monitoring data processing method, as a result inaccurate problem.

Description

A kind of arrester monitoring data on-line processing method and system
Technical field
The invention belongs to arrester on-line monitoring technique fields, and in particular to a kind of arrester monitoring data online processing side Method and system.
Background technique
Arrester is the important electrical that power equipment is protected in power grid from overvoltage injury, reliability of operation The safety of electric system will be directly affected.In recent years, the AC gapless Oxide Arrester in substation operation is due to valve block Aging so that electric property is degenerated so as to cause explosion accident happen occasionally, bring massive losses to national economy, give power grid Safe operation brings serious threat.Arrester is implemented to monitor on-line, can effectively monitor arrester internal flaw in time, It finds and debugs early, avoid that Explosion of on Arrester occurs, ensure safe operation of power system.
In order to monitor AC gapless Oxide Arrester valve block nonlinear resistance property, the best way be monitoring Current in resistance property.Accurate current in resistance property is obtained, the total current and busbar voltage of synchronous acquisition arrester are needed.It is existing usually to adopt It is calculated with the mode of Fourier transformation, least square method fitting, frequency, phase angle.But due to arrester electric current and reality It bears electric voltage frequency to be different, causes the continuous wave of the variation of the phase angle generating period of electric current and voltage and frequency It is dynamic, cause calculated result not accurate enough.
Summary of the invention
The purpose of the present invention is to provide a kind of arrester monitoring data on-line processing method and systems, to solve existing keep away The problem of thunder device monitoring data on-line processing method calculated result inaccuracy.
In order to solve the above technical problems, the technical solution of the present invention is as follows:
The present invention provides a kind of arrester monitoring data on-line processing methods, comprising the following steps:
1) each phase current signal of synchronous acquisition arrester and each associated bus voltage signal, to collected at least two weeks The signal of wave carries out whole wave Fourier's operation every N number of sampled point;
2) amplitude and initial phase angle of each phase current and each associated bus voltage are calculated according to step 1) operation result;
3) initial phase angle of each phase current signal and each associated bus voltage signal obtained to step 2) operation is modified, The initial phase angle α [k+1] being calculated with latter k+1 times subtracts k initial phase angle α [k],
If α [k+1]-α [k] > β, α [k+1]=- 360 ° of α [k+1],
α if [k+1]-α [k] <-β, α [k+1]=+ 360 ° of α [k+1];
Wherein k=1,2,3..., β are related with the highest frequency that power frequency and power frequency change;
4) coefficient a, b are acquired using least square method fitting a straight line y=ax+b for the data of each group k and α [k], b is The final initial phase angle of each phase current and each associated bus voltage, signal frequency are acquired by a.
The present invention also provides a kind of arrester monitoring data Online Processing Systems, including current acquisition unit, voltage to adopt Collection unit, processor and memory, the processor receive the signal of the current acquisition unit and voltage acquisition unit;It is described Processor, which executes, stores the instruction to realize following method and step in memory:
1) each phase current signal of synchronous acquisition arrester and each associated bus voltage signal, to collected at least two weeks The signal of wave carries out whole wave Fourier's operation every N number of sampled point;
2) amplitude and initial phase angle of each phase current and each associated bus voltage are calculated according to step 1) operation result;
3) initial phase angle of each phase current signal and each associated bus voltage signal obtained to step 2) operation is modified, The initial phase angle α [k+1] being calculated with latter k+1 times subtracts k initial phase angle α [k],
If α [k+1]-α [k] > β, α [k+1]=- 360 ° of α [k+1],
α if [k+1]-α [k] <-β, α [k+1]=+ 360 ° of α [k+1];
Wherein k=1,2,3..., β are related with the highest frequency that power frequency and power frequency change;
4) coefficient a, b are acquired using least square method fitting a straight line y=ax+b for the data of each group k and α [k], b is The final initial phase angle of each phase current and each associated bus voltage, signal frequency are acquired by a.
Beneficial effects of the present invention:
It is found out by carrying out whole wave Fourier transformation to current acquisition unit and the collected signal of voltage acquisition unit Initial phase angle is modified initial phase angle according to the variation of power frequency, then utilizes least square method fitting a straight line, acquires each phase current The final initial phase angle and frequency of signal and each associated bus voltage signal eliminate the week of the phase angle generation of electric current and voltage The variation of phase property solves the problems, such as existing arrester online monitoring data processing method calculated result inaccuracy.
Further, further include step 5), judge that Current Voltage effectively runs definite value, according to pass through frequency, phase relation After the stability of calculation medium loss value, according to each phase phase difference for calculating arrester electric current and the busbar voltage, then basis Phase difference calculating current in resistance property, the size of the current in resistance property are equal to total current multiplied by the cosine of Current Voltage phase difference.
Further, system further includes the communication integrated management unit for signal synchronous collection.
Detailed description of the invention
Fig. 1 is two cycle schematic diagrames of the method for the present invention signal;
Fig. 2 is two cycle initial phase angle schematic diagrames of the method for the present invention;
Fig. 3 is schematic diagram after the method for the present invention initial phase angle least square method fitting a straight line;
Fig. 4 is of the invention based on serial bus arrester on-Line Monitor Device system schematic.
Specific embodiment
To keep the objectives, technical solutions, and advantages of the present invention clearer, with reference to the accompanying drawings and embodiments, to the present invention It is described in further detail.
The specific implementation step of method provided by the invention are as follows:
As shown in Figure 1, current acquisition unit and the synchronous acquisition 2 of voltage acquisition unit one time cycle totally 512 sampled points, All-wave Fourier's operation is carried out every 16 sampled points to two cycles, 16 calculating knots can be obtained in 512 sampled points altogether Fruit.The amplitude of whole wave Fourier transformation, calculating current and voltage, and then the initial phase angle of calculating current and voltage, obtain electric current Initial phase angle as shown in Fig. 2, altogether can be obtained 16 calculated results.
The initial phase angle of each phase current signal and each associated bus voltage signal that obtain to operation is modified, with rear k+1 The secondary initial phase angle α [k+1] being calculated subtracts k initial phase angle α [k],
If α [k+1]-α [k] > β, α [k+1]=- 360 ° of α [k+1],
α if [k+1]-α [k] <-β, α [k+1]=+ 360 ° of α [k+1];
Wherein k=1,2,3..., β are related with the highest frequency of power frequency and power frequency measure of the change;Power frequency is 50Hz, i.e., one Period is 0.02s, in one cycle 360 ° of angle change, and when frequency is 65Hz, a cycle time is 0.01538s pairs Answer 360 ° of angle change, in 65Hz the corresponding angle of 0.02/16s be β be equal to 0.02s/16 and 360 products again divided by 0.01538 obtains 29.25 °, is approximately 30 °.
As shown in figure 3, the data using least square method about each group k and α [k], fitting a straight line y=ax+b, are acquired each The final initial phase angle b and signal frequency of phase current and each associated bus voltage,
Wherein signal frequency acquires the ÷ of f=a × 50 22.5 by straight slope a, and signal frequency includes electric voltage frequency and electric current Frequency.
Communication synthesis administrative unit poll acquisition unit receives message, and processor parses message to obtain respective counts According to, by the practical 1 interval ABC three-phase current acquisition unit of arrester respectively with the consistent item of voltage cell sample-synchronous serial number Under part, judge that Current Voltage effectively runs definite value, after through frequency, the stability of phase relation calculation medium loss value, According to each phase phase difference for calculating arrester electric current and the busbar voltage, current in resistance property size is equal to total current multiplied by Current Voltage Thus the cosine of phase difference judges the degradation of arrester.
The present invention also provides a kind of arrester monitoring data Online Processing System, system includes current acquisition unit, electricity Press acquisition unit, processor, memory and communication management unit.As shown in figure 4, the communication management unit of system passes through RS485 Bus issues synchronous acquisition order to voltage acquisition unit and each arrester current acquisition unit, and acquisition unit FPGA receives order Trigger AD7606 sampling.Then serial number byte, the report sent on acquisition unit are synchronized to addition in above-mentioned acquisition unit polling message Literary also band synchronizes serial number byte, and it is that synchronous serial number is used to distinguish for which secondary synchronous acquisition order issued.
Communication synthesis administrative unit poll acquisition unit receives message, and processor parses message to obtain respective counts According to, by the practical 1 interval ABC three-phase current acquisition unit of arrester respectively with the consistent item of voltage cell sample-synchronous serial number Under part, according to voltage ABC three-phase initial phase angle, the initial phase angle of current three-phase, calculate with the phase difference of corresponding busbar voltage, thus most Current in resistance property is calculated eventually.
Integrated management unit is communicated by MMS and station end monitor supervision platform communication, administrative staff can real time inspection arrester prison The parameter state of measured data Online Processing System.

Claims (5)

1. a kind of arrester monitoring data on-line processing method, which comprises the following steps:
1) each phase current signal of synchronous acquisition arrester and each associated bus voltage signal, to collected at least two cycle Signal carries out whole wave Fourier's operation every N number of sampled point;
2) amplitude and initial phase angle of each phase current and each associated bus voltage are calculated according to step 1) operation result;
3) initial phase angle of each phase current signal and each associated bus voltage signal obtained to step 2) operation is modified, after K+1 times the initial phase angle α [k+1] being calculated subtracts k initial phase angle α [k],
If α [k+1]-α [k] > β, α [k+1]=- 360 ° of α [k+1],
α if [k+1]-α [k] <-β, α [k+1]=+ 360 ° of α [k+1];
Wherein k=1,2,3..., β are related with the highest frequency that power frequency and power frequency change;
4) coefficient a, b are acquired using least square method fitting a straight line y=ax+b for the data of each group k and α [k], b is each phase The final initial phase angle of electric current and each associated bus voltage, signal frequency are acquired by a.
2. arrester monitoring data on-line processing method according to claim 1, which is characterized in that it further include step 5), Judge that Current Voltage effectively runs definite value, after through frequency, the stability of phase relation calculation medium loss value, according to meter Each phase phase difference for calculating arrester electric current and the busbar voltage, then according to phase difference calculating current in resistance property, the current in resistance property Size be equal to total current multiplied by Current Voltage phase difference cosine.
3. a kind of arrester monitoring data Online Processing System, including current acquisition unit, voltage acquisition unit, processor and deposit Reservoir, the processor receive the signal of the current acquisition unit and voltage acquisition unit;It is characterized in that, the processor It executes and stores the instruction to realize following method and step in memory:
1) each phase current signal of synchronous acquisition arrester and each associated bus voltage signal, to collected at least two cycle Signal carries out whole wave Fourier's operation every N number of sampled point;
2) amplitude and initial phase angle of each phase current and each associated bus voltage are calculated according to step 1) operation result;
3) initial phase angle of each phase current signal and each associated bus voltage signal obtained to step 2) operation is modified, after K+1 times the initial phase angle α [k+1] being calculated subtracts k initial phase angle α [k],
If α [k+1]-α [k] > β, α [k+1]=- 360 ° of α [k+1],
α if [k+1]-α [k] <-β, α [k+1]=+ 360 ° of α [k+1];
Wherein k=1,2,3..., β are related with the highest frequency that power frequency and power frequency change;
4) coefficient a, b are acquired using least square method fitting a straight line y=ax+b for the data of each group k and α [k], b is each phase The final initial phase angle of electric current and each associated bus voltage, signal frequency are acquired by a.
4. arrester monitoring data Online Processing System according to claim 3, which is characterized in that it further include step 5), Judge that Current Voltage effectively runs definite value, after through frequency, the stability of phase relation calculation medium loss value, according to meter Each phase phase difference for calculating arrester electric current and the busbar voltage, then according to phase difference calculating current in resistance property, the current in resistance property Size be equal to total current multiplied by Current Voltage phase difference cosine.
5. arrester monitoring data Online Processing System according to claim 3 or 4, which is characterized in that further include being used for The communication integrated management unit of signal synchronous collection.
CN201811210554.9A 2018-10-17 2018-10-17 Lightning arrester monitoring data online processing method and system Active CN109283385B (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110244144A (en) * 2019-05-28 2019-09-17 许昌许继软件技术有限公司 A kind of arrester state monitoring method and AC Data Acquisition method
CN111323665A (en) * 2020-03-18 2020-06-23 合肥瀚度电力科技有限公司 Lightning arrester monitoring device, method and system based on GPS time service ratio correction

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH02193528A (en) * 1989-01-21 1990-07-31 Giichiro Kato Lightning arrestor for high-sensitivity, large-capacity and low-pressure circuit
CN101587147A (en) * 2009-06-25 2009-11-25 中国电力科学研究院 A kind of synchronous phasor measuring device carries out the method for phasor correction
CN102269803A (en) * 2010-06-04 2011-12-07 北京化工大学 Method for correcting low-frequency components in discrete spectrum based on time delay
CN103091545A (en) * 2013-02-21 2013-05-08 南京磐能电力科技股份有限公司 Sinusoidal signal phasor half-wave computing method irrelevant to frequency
CN104020350A (en) * 2014-06-23 2014-09-03 哈尔滨同为电气股份有限公司 Voltage fundamental component detection method for overcoming frequency perturbation
CN104142421A (en) * 2013-05-07 2014-11-12 常州顺创电气科技有限公司 Substation equipment insulation online monitoring system and working method thereof
CN104865438A (en) * 2015-06-15 2015-08-26 江苏理工学院 Method for measuring resistive current fundamental wave of zinc oxide arrester
CN105182160A (en) * 2015-09-21 2015-12-23 厦门大恒科技有限公司 On-line SPD microampere current leakage detecting device
US20170045567A1 (en) * 2015-08-10 2017-02-16 Xj Group Corporation Monitoring method and system of arrester applied to smart substation
CN106597199A (en) * 2016-12-16 2017-04-26 国家电网公司 Judgment method of GIS device built-in lightning arrester lead wire phase marking error
CN106970264A (en) * 2017-03-02 2017-07-21 浙江大学 A kind of improvement phase difference correction method for considering mains frequency rate of change

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH02193528A (en) * 1989-01-21 1990-07-31 Giichiro Kato Lightning arrestor for high-sensitivity, large-capacity and low-pressure circuit
CN101587147A (en) * 2009-06-25 2009-11-25 中国电力科学研究院 A kind of synchronous phasor measuring device carries out the method for phasor correction
CN102269803A (en) * 2010-06-04 2011-12-07 北京化工大学 Method for correcting low-frequency components in discrete spectrum based on time delay
CN103091545A (en) * 2013-02-21 2013-05-08 南京磐能电力科技股份有限公司 Sinusoidal signal phasor half-wave computing method irrelevant to frequency
CN104142421A (en) * 2013-05-07 2014-11-12 常州顺创电气科技有限公司 Substation equipment insulation online monitoring system and working method thereof
CN104020350A (en) * 2014-06-23 2014-09-03 哈尔滨同为电气股份有限公司 Voltage fundamental component detection method for overcoming frequency perturbation
CN104865438A (en) * 2015-06-15 2015-08-26 江苏理工学院 Method for measuring resistive current fundamental wave of zinc oxide arrester
US20170045567A1 (en) * 2015-08-10 2017-02-16 Xj Group Corporation Monitoring method and system of arrester applied to smart substation
CN105182160A (en) * 2015-09-21 2015-12-23 厦门大恒科技有限公司 On-line SPD microampere current leakage detecting device
CN106597199A (en) * 2016-12-16 2017-04-26 国家电网公司 Judgment method of GIS device built-in lightning arrester lead wire phase marking error
CN106970264A (en) * 2017-03-02 2017-07-21 浙江大学 A kind of improvement phase difference correction method for considering mains frequency rate of change

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110244144A (en) * 2019-05-28 2019-09-17 许昌许继软件技术有限公司 A kind of arrester state monitoring method and AC Data Acquisition method
CN110244144B (en) * 2019-05-28 2021-11-16 许昌许继软件技术有限公司 Lightning arrester state monitoring method and alternating current data acquisition method
CN111323665A (en) * 2020-03-18 2020-06-23 合肥瀚度电力科技有限公司 Lightning arrester monitoring device, method and system based on GPS time service ratio correction
CN111323665B (en) * 2020-03-18 2022-06-28 合肥瀚度电力科技有限公司 Lightning arrester monitoring device, method and system based on GPS time service ratio correction

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