CN102435973A - Calibration apparatus of capacitive equipment insulation on-line monitoring system and method thereof - Google Patents

Calibration apparatus of capacitive equipment insulation on-line monitoring system and method thereof Download PDF

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Publication number
CN102435973A
CN102435973A CN2011103859009A CN201110385900A CN102435973A CN 102435973 A CN102435973 A CN 102435973A CN 2011103859009 A CN2011103859009 A CN 2011103859009A CN 201110385900 A CN201110385900 A CN 201110385900A CN 102435973 A CN102435973 A CN 102435973A
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CN
China
Prior art keywords
signal
source module
line monitoring
capacitive
output
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CN2011103859009A
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Chinese (zh)
Inventor
朱凯
雷民
张军
王斯琪
徐子立
郭子娟
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国网电力科学研究院
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Priority to CN2011103859009A priority Critical patent/CN102435973A/en
Publication of CN102435973A publication Critical patent/CN102435973A/en

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Abstract

The invention provides a calibration apparatus of a capacitive equipment insulation on-line monitoring system. The apparatus comprises a controller, three signal generation modules, two precision current source modules, a reference precision voltage source module and a precision voltage transformer. An output control signal of the controller is respectively connected with control terminals of the three signal generation modules; outputs of the two signal generation modules are respectively connected with inputs of the two corresponded precision current source modules; and the two precision current source modules respectively output corresponded current components. Besides, an output of another signal generation module is connected with an input of the reference precision voltage source module; an output of the precision voltage source module is connected with a primary side of the precision voltage transformer; and a secondary of the precision voltage source module outputs a corresponded standard voltage signal. According to the calibration apparatus provided in the invention, high accuracy calibration can be carried out on main measuring functions of a capacitive equipment insulation on-line monitoring system, wherein the measuring functions include capacitance and dielectric loss factor measuring functions; and moreover, magnitude traceablility can be conveniently and effectively carried out on the generated standard signal.

Description

Capacitive apparatus insulated on-line monitoring system calibration equipment and method

 

Technical field

The present invention relates to capacitive apparatus insulated on-line monitoring technique, belong to calibration, calibrating and the detection range of power test instrument, relate in particular to a kind of capacitive apparatus insulated on-line monitoring system calibration equipment and method.

 

Background technology

Capacitive apparatus insulated on-line monitoring system is the equipment that is used to monitor electric capacity and dielectric dissipation factor; To judging that condenser-type terminal, condenser type current transformer and other capacitive apparatus insulated state have important effect in the electric system; The status monitoring means that can be used as crucial power equipment are found the latency fault, the generation of prevention sudden accident.Lacking corresponding calibration equipment at present effectively calibrates or examines and determine capacitive apparatus insulated on-line monitoring system; Can't judge the quality of capacitive apparatus insulated on-line monitoring system measurement data; But therefore be badly in need of the capacitive apparatus insulated on-line monitoring system calibration equipment that design has good traceability; High and the capacitive apparatus insulated on-line monitoring system calibration equipment that can effectively be traced to the source of accuracy just satisfies the urgent needs of present verification work.

The bibliographical information of relevant this respect for example application number is the utility model patent of 201020599275.9 the capacitive apparatus insulated state on-line detector of by name distributed transformer station; The capacitive apparatus insulated state on-line detector of a kind of distributed transformer station is disclosed; Data acquisition unit, data processor and system controller by connecting successively constitute; It is characterized in that data acquisition unit comprises some sensings unit; Data processor comprises the on-site signal processing unit that each sensing unit correspondence is connected, and system controller then comprises host computer, communication unit etc.Adopt the online one that is detected on of the multiple electrical equipment of the utility model collection; Comprise lightning arrester, bushing shell for transformer, current transformer and voltage transformer (VT) etc., adopt unified communication, real-time is good; Antijamming capability is strong; The state of insulation that can reflect capacitive apparatus and lightning arrester, and, guarantee its safe operation with this repair based on condition of component that instructs equipment.Yet; Above-mentioned patent does not relate to a kind of calibration equipment capacitive apparatus insulated on-line monitoring system is effectively calibrated or examined and determine; And can't judge the quality of capacitive apparatus insulated on-line monitoring system measurement data, and capacitive apparatus insulated on-line monitoring system calibration equipment is not still seen relevant report.

In view of this; Be necessary to provide a kind of capacitive apparatus insulated on-line monitoring system calibration equipment and method; Utilizing this calibration equipment can be the verification that electric capacity and dielectric dissipation factor measurement function carry out pin-point accuracy to the main measurement function of capacitive apparatus insulated on-line monitoring system, and can carry out conveniently, effectively carrying out magnitude tracing to electric capacity and dielectric dissipation factor.

 

Summary of the invention

Technical matters to be solved by this invention is: to the principle of work of existing capacitive apparatus insulated on-line monitoring system; But take into account the traceability of calibration equipment; A kind of capacitive apparatus insulated on-line monitoring system calibration equipment and method are provided; The demand of the capacitive apparatus insulated on-line monitoring system of verification is satisfied in accuracy, but and have a good traceability; The core thinking is: calibrating installation output amplitude ratio and phase differential be controlled 50Hz voltage and current signal accurately; Thereby effective verification work is carried out in the measurement that utilizes calibration equipment that the present invention designs and method can be electric capacity and dielectric dissipation factor to the main measurement function of capacitive apparatus insulated on-line monitoring system.

The technical scheme that the present invention adopted is: a kind of capacitive apparatus insulated on-line monitoring system calibration equipment; By controller, three signal generator modules, two precision current source modules, form with reference to accurate voltage source module and accurate voltage mutual inductor; It is characterized in that: the output control signal of controller connects the control end of said three signal generator modules respectively; Wherein there is the output of two signal generator modules to connect the input of corresponding two precision current source modules respectively; Said two precision current source modules are exported corresponding current component I1 and I2 respectively, and the output of normalized current signal is provided; The output of another one signal generator module connects said input with reference to the accurate voltage source module, and the output of said accurate voltage source module is connected with the former limit of said accurate voltage mutual inductor, the secondary output corresponding standard voltage signal U of accurate voltage mutual inductor.

Aforesaid capacitive apparatus insulated on-line monitoring system calibration equipment; It is characterized in that: said three signal generator modules adopt based on Direct Digital Synthesizer DDS chip AD9951 circuit and realize, can produce amplitude independently, the level and smooth sinusoidal signal unit of height that phase angle is adjustable.

Aforesaid capacitive apparatus insulated on-line monitoring system calibration equipment is characterized in that: said two precision current source modules and said the employing based on accurate amplifier OPA228 chip with reference to the accurate voltage source module constitute.

The present invention also provides a kind of capacitive apparatus insulated on-line monitoring system method of calibration, adopts aforesaid capacitive apparatus insulated on-line monitoring system calibration equipment, it is characterized in that, comprises the steps:

1) under the effect of controller; Each signal generator module produces amplitude independently, the level and smooth sinusoidal signal of height that phase place is adjustable; These sinusoidal signals to back level respectively independently the precision current source module, encourage with reference to accurate voltage source module, accurate voltage mutual inductor; Thereby form separate electric current and voltage drive signals; Current drive signal is through precision current source module outputting standard current signal I1 and I2, and voltage drive signals is then through driving accurate voltage mutual inductor, its secondary output reference voltage signal U;

2) through adjustment 1 road current signal and 1 road voltage signal; Perhaps the amplitude between 2 road current signals compares and phase differential; Simulate different electric capacitys and dielectric dissipation factor, thereby reach the purpose of capacitive apparatus insulated on-line monitoring system electric capacity of verification and dielectric dissipation factor measurement function.

The invention has the beneficial effects as follows: use this capacitive apparatus insulated on-line monitoring system calibration equipment; Can be the verification that electric capacity and dielectric dissipation factor measurement function carry out pin-point accuracy to the main measurement function of capacitive apparatus insulated on-line monitoring system, and the standard signal that is produced can make things convenient for, effectively carry out magnitude tracing.

 

Description of drawings

Fig. 1 is the capacitive apparatus insulated on-line monitoring system calibration equipment schematic diagram of the embodiment of the invention.

 

Embodiment

In order to understand the present invention better, further illustrate content of the present invention below in conjunction with embodiment, but content of the present invention not only is confined to following embodiment.Those skilled in the art can do various changes or modification to the present invention, and these equivalent form of values are equally within the listed claims limited range of the application.

Mark among Fig. 1: 1-controller, 2,3,4-signal generator module, 5,6-precision current source module, 7-with reference to the accurate voltage source module, 8-accurate voltage mutual inductor, I1-electric current 1, I2-electric current 2, U-reference voltage.

Referring to shown in Figure 1, the capacitive apparatus insulated on-line monitoring system calibration equipment schematic diagram of the embodiment of the invention.Connect the control end of signal generator module 2,3,4 by the output control signal of controller 1, the output of signal generator module 2,3 connects the input of corresponding precision current source module 5,6 respectively, and precision current source module 5,6 is output as electric current 1 and electric current 2.The output of signal generator module 4 connects the input with reference to accurate voltage source module 7, is connected accurate voltage mutual inductor 8 secondary generation voltage output reference voltage U with accurate voltage mutual inductor 8 former limits with reference to the output terminal of accurate voltage source module 7.

Its principle of work is: under the control action of controller 1 (being specially TMS320F2812); Each signal generator module 2,3,4 (realizing based on DDS chip AD9951) can produce amplitude independently, the level and smooth sinusoidal signal unit of height that phase angle is adjustable; These sinusoidal signal unit can to back level separately independently precision current source module 5,6 (constituting) based on accurate amplifier OPA228 chip, encourage with reference to accurate voltage source module 7 (constituting), accurate voltage mutual inductor 8 based on accurate amplifier OPA228 chip; Thereby form separate current signal I1, I2 and voltage signal U; Amplitude and phase angle through adjustment current signal and voltage signal can simulate different electric capacitys and dielectric dissipation factor.

In the present embodiment, signal generator module 2,3,4 has taked to produce easily based on the Direct Digital synthetic technology of DDS chip that frequency stabilization is adjustable, amplitude stability is adjustable, phase stabilization is adjustable and the level and smooth stable sinusoidal signal of height of curve.

In the present embodiment, in design, taked the mode of " virtual medium loss factor standard ", designed precision current source module 5,6 and with reference to accurate voltage source module 7.

Calibration equipment principle of work: under the effect of control module; Each signal generator module can produce amplitude independently, the level and smooth sinusoidal signal of height that phase place is adjustable; These sinusoidal signals can to back level respectively independently the precision current source module, encourage with reference to accurate voltage source module, accurate voltage mutual inductor; Thereby form separate electric current and voltage drive signals; Current drive signal is through precision current source module outputting standard current signal, and voltage drive signals is then through driving accurate voltage mutual inductor, its secondary output reference voltage signal.Through regulating the amplitude ratio and the phase differential of 2 road current signals or 1 road current signal and 1 road voltage signal, finally reach the purpose of capacitive apparatus insulated on-line monitoring system electric capacity of verification and dielectric dissipation factor measurement function.

Signal generator module is taked the circuit based on Direct Digital Synthesizer DDS chip AD9951, comes to produce easily the sinusoidal signal that amplitude stability is adjustable, phase stabilization is adjustable and height of curve is level and smooth with the Direct Digital synthetic technology of DDS chip.Said two precision current source modules and said the employing based on accurate amplifier OPA228 chip with reference to the accurate voltage source module constitute.

Secondly, the present invention has also adopted following core technology in design:

1, the sinusoidal signal generation module of the adjustable and curve smoothing of frequency 50Hz, amplitude and phase stabilization

In order to reach the purpose of verification, at first need generate 3 basic sinusoidal signals, these sinusoidal signals will be used for encouraging rearmounted precision current source module and accurate voltage source module and producing corresponding standard current signal and reference voltage signal.In order at first to obtain the sinusoidal signal unit of the adjustable and curve smoothing of amplitude and frequency stabilization, having taked the Direct Digital synthetic technology is that the DDS chip produces sinusoidal signal.The Direct Digital synthetic technology can produce easily in the present invention that amplitude stability is adjustable, phase stabilization is adjustable and the level and smooth stable sinusoidal signal of height of curve.Wherein: the frequency of sinusoidal signal is highly stable 50Hz power frequency component; The accuracy of sinusoidal signal phase place can reach 0.0002rad; The sinusoidal signal curve is very level and smooth, can't see " ladder " through ordinary oscilloscope, the effect that this height is level and smooth can not used follow-up filtering circuit fully, thereby has significantly reduced the amplitude that filtering circuit brings and the negative effect of phase place.

2, realize " virtual medium loss factor standard " through design precision current source module and reference voltage source module.

The mode that the present invention has taked " module " to change in design to the precision current source circuit and the reference voltage source modular circuit of core.The input signal of each precision current source module and reference voltage source module is an independently sinusoidal signal; This signal is from the DDS chip; Under the excitation of the adjustable sinusoidal signal of amplitude-frequency independently; Precision current source module and reference voltage source module can be exported electric current, the voltage signal of different amplitudes, phase place respectively, and the precision current source module chosen high performance device, near the infinitely-great ideal current source requirement of output impedance.Between 2 road precision current source modules and precision current source module and adjustable, reach the purpose of simulation medium loss factor with reference to phase place precision between the accurate voltage source module.The present invention has formed following characteristics: output current signal and reference voltage signal amplitude and phase adjustment range are big.Can the analog electrical capacity through regulating the amplitude ratio, the control phase difference can the simulation medium loss factor, therefore can realize " virtual medium loss factor standard ".Amplitude and phase place through to voltage signal and electric current are traced to the source respectively, can guarantee trace to the source result's validity of this calibration equipment, have guaranteed the electric capacity that this calibration equipment produces and the accuracy of dielectric dissipation factor.

Adopt a kind of capacitive apparatus insulated on-line monitoring system method of calibration of capacitive apparatus insulated on-line monitoring system calibration equipment of the present invention, comprise the steps:

1) under the effect of controller; Each signal generator module produces amplitude independently, the level and smooth sinusoidal signal of height that phase place is adjustable; These sinusoidal signals to back level respectively independently the precision current source module, encourage with reference to accurate voltage source module, accurate voltage mutual inductor; Thereby form separate electric current and voltage drive signals; Current drive signal is through precision current source module outputting standard current signal I1 and I2, and voltage drive signals is then through driving accurate voltage mutual inductor, its secondary output reference voltage signal U;

2) through adjustment 1 road current signal and 1 road voltage signal; Perhaps the amplitude between 2 road current signals compares and phase differential; Simulate different electric capacitys and dielectric dissipation factor, thereby reach the purpose of capacitive apparatus insulated on-line monitoring system electric capacity of verification and dielectric dissipation factor measurement function.

The content of not doing in this instructions to describe in detail belongs to this area professional and technical personnel's known prior art.

Claims (4)

1. capacitive apparatus insulated on-line monitoring system calibration equipment; By controller, three signal generator modules, two precision current source modules, form with reference to accurate voltage source module and accurate voltage mutual inductor; It is characterized in that: the output control signal of controller connects the control end of said three signal generator modules respectively; Wherein there is the output of two signal generator modules to connect the input of corresponding two precision current source modules respectively; Said two precision current source modules are exported corresponding current component I1 and I2 respectively, and the output of normalized current signal is provided; The output of another one signal generator module connects said input with reference to the accurate voltage source module, and the output of said accurate voltage source module is connected with the former limit of said accurate voltage mutual inductor, the secondary output corresponding standard voltage signal U of accurate voltage mutual inductor.
2. capacitive apparatus insulated on-line monitoring system calibration equipment according to claim 1; It is characterized in that: said three signal generator modules adopt based on Direct Digital Synthesizer DDS chip AD9951 circuit and realize, can produce amplitude independently, the level and smooth sinusoidal signal unit of height that phase angle is adjustable.
3. capacitive apparatus insulated on-line monitoring system calibration equipment according to claim 1 is characterized in that: said two precision current source modules and said the employing based on accurate amplifier OPA228 chip with reference to the accurate voltage source module constitute.
4. a capacitive apparatus insulated on-line monitoring system method of calibration adopts capacitive apparatus insulated on-line monitoring system calibration equipment as claimed in claim 1, it is characterized in that, comprises the steps:
1) under the effect of controller; Each signal generator module produces amplitude independently, the level and smooth sinusoidal signal of height that phase place is adjustable; These sinusoidal signals to back level respectively independently the precision current source module, encourage with reference to accurate voltage source module, accurate voltage mutual inductor; Thereby form separate electric current and voltage drive signals; Current drive signal is through precision current source module outputting standard current signal I1 and I2, and voltage drive signals is then through driving accurate voltage mutual inductor, its secondary output reference voltage signal U;
2) through adjustment 1 road current signal and 1 road voltage signal; Perhaps the amplitude between 2 road current signals compares and phase differential; Simulate different electric capacitys and dielectric dissipation factor, thereby reach the purpose of capacitive apparatus insulated on-line monitoring system electric capacity of verification and dielectric dissipation factor measurement function.
CN2011103859009A 2011-11-29 2011-11-29 Calibration apparatus of capacitive equipment insulation on-line monitoring system and method thereof CN102435973A (en)

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Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103116150A (en) * 2013-01-30 2013-05-22 中国电力科学研究院 Verifying device of insulated online monitoring equipment of oxide arrester
CN103454609A (en) * 2013-09-11 2013-12-18 国家电网公司 Debugging platform of on-line monitoring device of capacitive equipment
CN103760508A (en) * 2013-11-28 2014-04-30 国家电网公司 Virtual dielectric loss device and detecting method thereof
CN104360299A (en) * 2014-11-19 2015-02-18 云南电网公司电力科学研究院 On-site wireless inspection device and method for capacitive type device on-line monitoring system
CN104793170A (en) * 2015-05-13 2015-07-22 国网重庆市电力公司电力科学研究院 Field measurement standard device and verification mode of insulated online monitoring device
CN104849568A (en) * 2015-05-14 2015-08-19 广东电网有限责任公司电力科学研究院 Signal-adjustment-based monitoring apparatus detection platform of transformer casing tube
CN105974344A (en) * 2016-04-19 2016-09-28 中国电力科学研究院 Calibration system and method for relative dielectric loss and electric capacity detector
CN106443537A (en) * 2016-04-26 2017-02-22 中国电力科学研究院 Calibration method for online capacitive equipment insulation parameter monitoring device and calibration equipment
CN107884737A (en) * 2017-11-13 2018-04-06 国网福建省电力有限公司 The live capacitive apparatus on-line monitoring check system and method for wireless high-precise synchronization

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Publication number Priority date Publication date Assignee Title
CN101271152A (en) * 2008-05-06 2008-09-24 山东电力研究院 Capacitance type equipment insulation on-line monitoring system calibration method and device
CN101526562A (en) * 2009-04-22 2009-09-09 中国电力科学研究院 Distributed wireless high-voltage equipment insulating live testing system and testing method
CN102062846A (en) * 2009-11-14 2011-05-18 甘肃电力科学研究院 Method and device for correcting online tester of MOA leakage current
CN202433515U (en) * 2011-11-29 2012-09-12 国网电力科学研究院 Insulated on-line monitoring system verifying device for capacitive device

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101271152A (en) * 2008-05-06 2008-09-24 山东电力研究院 Capacitance type equipment insulation on-line monitoring system calibration method and device
CN101526562A (en) * 2009-04-22 2009-09-09 中国电力科学研究院 Distributed wireless high-voltage equipment insulating live testing system and testing method
CN102062846A (en) * 2009-11-14 2011-05-18 甘肃电力科学研究院 Method and device for correcting online tester of MOA leakage current
CN202433515U (en) * 2011-11-29 2012-09-12 国网电力科学研究院 Insulated on-line monitoring system verifying device for capacitive device

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103116150A (en) * 2013-01-30 2013-05-22 中国电力科学研究院 Verifying device of insulated online monitoring equipment of oxide arrester
CN103454609A (en) * 2013-09-11 2013-12-18 国家电网公司 Debugging platform of on-line monitoring device of capacitive equipment
CN103454609B (en) * 2013-09-11 2015-10-07 国家电网公司 A kind of capacitive apparatus on-Line Monitor Device debug platform
CN103760508A (en) * 2013-11-28 2014-04-30 国家电网公司 Virtual dielectric loss device and detecting method thereof
CN104360299A (en) * 2014-11-19 2015-02-18 云南电网公司电力科学研究院 On-site wireless inspection device and method for capacitive type device on-line monitoring system
CN104793170A (en) * 2015-05-13 2015-07-22 国网重庆市电力公司电力科学研究院 Field measurement standard device and verification mode of insulated online monitoring device
CN104849568A (en) * 2015-05-14 2015-08-19 广东电网有限责任公司电力科学研究院 Signal-adjustment-based monitoring apparatus detection platform of transformer casing tube
CN104849568B (en) * 2015-05-14 2016-06-01 广东电网有限责任公司电力科学研究院 Based on the transformer bushing monitoring device detection platform of Signal Regulation
CN105974344A (en) * 2016-04-19 2016-09-28 中国电力科学研究院 Calibration system and method for relative dielectric loss and electric capacity detector
CN106443537A (en) * 2016-04-26 2017-02-22 中国电力科学研究院 Calibration method for online capacitive equipment insulation parameter monitoring device and calibration equipment
CN107884737A (en) * 2017-11-13 2018-04-06 国网福建省电力有限公司 The live capacitive apparatus on-line monitoring check system and method for wireless high-precise synchronization
CN107884737B (en) * 2017-11-13 2020-02-14 国网福建省电力有限公司 Wireless high-precision synchronous on-site capacitive equipment on-line monitoring and checking system and method

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Application publication date: 20120502