CN1414396A - Method and device for real time on line detection of metering current mulual inductor malfunction - Google Patents
Method and device for real time on line detection of metering current mulual inductor malfunction Download PDFInfo
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- CN1414396A CN1414396A CN 02119440 CN02119440A CN1414396A CN 1414396 A CN1414396 A CN 1414396A CN 02119440 CN02119440 CN 02119440 CN 02119440 A CN02119440 A CN 02119440A CN 1414396 A CN1414396 A CN 1414396A
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Abstract
The invented device is composed of a high-frequency excitation module, a signal coupling module, a signal sampling module, a signal processing module, a fault diagnostic module, a fault state output module, a power source module, a timing module, a fault state recording module, a fault state display module and a network communication module. Comparing with the prior art, the invented method provides the advantages of high accuracy, the good performance in real-time and strong capability on-line for detecting the fault of the metric current transformer.
Description
Affiliated technical field
The current transformer failure metering that the invention belongs in the electric energy metrical detects, and particularly relates to a kind of current transformer failure metering real-time on-line detecting method and device.
Background technology
In the prior art, current transformer failure metering detects, and normally detects at faults such as the artificial open circuit of the reduction of secondary coil insulating property, turn-to-turn short circuit, input and output terminal loose contact, transformer ratio, secondary output loop of metering current mulual inductor and short circuits.Its detection method by the artificial visually examine, is carried out casual inspection to the watt-hour meter in outward appearance, external cabling terminal and the electric power meter of metering current mulual inductor normally in the erecting stage of metering current mulual inductor.Its testing result is judged by following several modes usually: 1) whether improper metering determines whether metering current mulual inductor exists a small amount of faults that characterize such as input and output terminal loose contact, secondary output loop open circuit and short circuit according to the connection situation of the appearance change of metering current mulual inductor, external cabling terminal and the watt-hour meter in the electric power meter; 2) adopt common voltage table and reometer, the voltage and current of monitoring using electricity system, according to using electricity system voltage have or not and the variable quantity and the variation tendency of system power estimate whether metering current mulual inductor exists fault; 3) input end at electric network source installs prime dedicated test current transformer additional, judges according to the quantity of dedicated test current transformer and metering current mulual inductor secondary output current value quantity poor, performance number quantity difference poor, the electric degree number whether metering current mulual inductor exists fault.More than several detection modes in utilization, have defectives such as real-time, accuracy, poor reliability, the line detectability is subjected to restriction greatly and influence, very easily cause the untrue property and the uncertainty that detect with judged result, can not satisfy the request for utilization that current transformer failure metering is accurate, reliable, real-time online detects.
Summary of the invention
Current transformer failure metering real-time on-line detecting method and device in a kind of electric energy metrical that the objective of the invention is to provide at the deficiencies in the prior art, the accuracy that this detection method and device can effectively solve in the current transformer failure metering detection that has now in the electric energy metrical is low, real-time and poor reliability, can not realize key issues such as online detection, can realize that real-time online detects the various faults of metering current mulual inductor in the electric power meter, accurately judge all kinds of nature of troubles of current transformer, various accurate characterization information when in time output current transformer breaks down, the beginning and ending time of record and demonstration fault, separate etc., and failure message that can be by communication network real-time Transmission metering current mulual inductor, in time judging and handling detection method and the device that current mulual inductor malfunction provides a kind of novelty.
The technical solution adopted for the present invention to solve the technical problems is:
Current transformer failure metering real-time on-line detecting method and device, it by high frequency pumping module (1), signal coupling module (2), signal sampling module (3), signal processing module (4), fault judgement module (5), malfunction output module (6), power module (7), clock module (8), malfunction logging modle (9), malfunction display module (10), network communication module (11), etc. module form.Wherein: high frequency pumping module (1) is used to take place high-frequency excitation signal, and provides high-frequency excitation signal to signal coupling module (2), provides reference signal to signal processing module (4) simultaneously.Signal coupling module (2) links to each other with high frequency pumping module (1), signal sampling module (3), is used to isolate forceful electric power loop and the weak electrical loop of high frequency pumping module (1) and the weak electrical loop of signal sampling module (3) of metering current mulual inductor; The forceful electric power loop that signal coupling module (2) is also exported to metering current mulual inductor with the coupling of the high-frequency excitation signal of high frequency pumping module (1), and the high frequency feedback signal in metering current mulual inductor forceful electric power loop is coupled to signal sampling module (3).The high frequency feedback signal that signal sampling module (3) is used for metering current mulual inductor forceful electric power loop that signal coupling module (2) is provided carries out processing backward signal processing modules (4) such as real-time online signal sampling, amplification, filtering, shaping provides feedback signal.Signal processing module (4) links to each other with high frequency pumping module (1), signal sampling module (3), the reference signal that high frequency pumping module (1) provides is carried out processing such as analog to digital conversion, and the feedback signal that signal sampling module (3) provides carried out reference signal and feedback signal after handling being delivered to fault judgement module (5) after analog to digital conversion, digital filtering, fourier transform etc. handle.Fault judgement module (5) links to each other with signal processing module (4), signal to signal processing module (4) output carries out analysis and judgement, when metering current mulual inductor breaks down, deliver to malfunction output module (6) automatically to fault type and the separate judgement of classifying, and with judged result.Malfunction output module (6) links to each other with fault judgement module (5), and when metering current mulual inductor broke down, malfunction output module (6) was exported the current transformer failure metering type and taken place separate according to standard data format.
Power module (7) provides working power for the current transformer failure metering real time on-line detection device, include supply convertor, voltage stabilizer and backup battery group in the associated components of working power, when current transformer failure metering real time on-line detection device externally fed power supply dead electricity, power module (7) starts all kinds of faults that the backup battery group detects metering current mulual inductor.
Malfunction logging modle (9) links to each other with fault judgement module (5), clock module (8), and clock module (8) is used to provide the current time.When metering current mulual inductor broke down, the beginning and ending time of record trouble, fault type, generation were separate.Malfunction display module (10), it is made up of Chinese character base and Chinese character LCD two parts.Malfunction display module (10) links to each other with malfunction logging modle (9), when fault takes place maybe need consult dependent failure, and can Chinese character and digital dual mode demonstration dependent failure.Network communication module (11) links to each other with clock module (8), malfunction logging modle (9), by network communication module (11), communication protocol according to correlation standard, when metering current mulual inductor breaks down, in time send failure message to intra-office Surveillance center computing machine, to current transformer failure metering carry out in real time, Rapid Alarm, the various data recording information in the malfunction logging modle (9) can be provided simultaneously.
Current transformer failure metering real-time on-line detecting method provided by the invention and device, can realize that electric power meter real-time online to current transformer failure metering under various running environment detects, according to detection method provided by the invention and device, can judge accurately whether secondary coil insulating property reduction of metering current mulual inductor, turn-to-turn short circuit, input and output terminal loose contact, transformer ratio change and whether the secondary output loop opens a way and all kinds of faults such as short circuit, record shows that also beginning and ending time, fault type, the fault of fault is separate.The present invention has network communicating function, can report to the police to various faults in the electric power meter real-time.
Description of drawings
Accompanying drawing 1 is a modular structure block diagram of the present invention.
Accompanying drawing 2 is another modular structure block diagram of the present invention.
Embodiment
Be described as follows below in conjunction with accompanying drawing 1,2 pairs of current transformer failure metering real-time on-line detecting methods of the present invention of accompanying drawing and device:
In accompanying drawing 1, high frequency pumping module (1) is used to produce the high-frequency signal of certain frequency and amplitude, and high-frequency signal is exported to signal coupling module (2) as pumping signal, simultaneously high-frequency signal is exported to signal processing module (4) as reference signal.
Signal coupling module (2) is used to isolate high frequency pumping module (1) and metering current mulual inductor forceful electric power loop, and to metering current mulual inductor forceful electric power loop coupling output high-frequency excitation signal, signal coupling module (2) also is used for isolation signals sampling module (3) and metering current mulual inductor forceful electric power loop, and the high frequency feedback signal in metering current mulual inductor forceful electric power loop is coupled to signal sampling module (3), signal coupling module (2) is by the isolation coupling mode, effectively avoids the heavy current in metering current mulual inductor forceful electric power loop or high voltage influence and the destruction to current transformer failure metering real-time online measuring ability.
Signal sampling module (3) is used for the high frequency feedback signal in metering current mulual inductor forceful electric power loop that signal coupling module (2) is provided, carry out processing such as real-time online signal sampling, amplification, filtering, shaping, and the feedback signal after will handling is exported to signal processing module (4).
Signal processing module (4) is used for the feedback signal that signal sampling module (3) provides is carried out processing such as analog to digital conversion, digital filtering, fourier transform, remove electrical network fundamental signal and harmonic signal in the feedback signal, feedback signal is transformed into exports to fault judgement module (5) after not being subjected to the feedback phase digital signal that line voltage height and load current size influence and feeding back the amplitude digital signal.
Signal processing module (4) also is used for the reference signal that high frequency pumping module (1) provides is carried out analog-to-digital conversion process, and reference signal is transformed into reference phase digital signal and reference amplitude digital signal, exports to fault judgement module (5).
Fault judgement module (5) is used for reference phase digital signal that signal processing module (4) is provided, the reference amplitude digital signal, feedback phase digital signal and feedback amplitude digital signal are carried out the current transformer failure metering analysis and judgement, its fault judgement principle is: adopt phase-comparison method, the amplitude relative method, adaptive algorithm etc., in feedback signal complicated and changeable, extract the various characteristic signals of current transformer failure metering, and according to the characteristic signal of current transformer failure metering, whether metering Current Transformer Secondary coil insulation performance reduces in the analysis and judgement electric energy metrical, whether short circuit of turn-to-turn, whether loose contact of input and output terminal, whether transformer ratio changes, and whether the secondary output loop opens a way and fault such as short circuit, and to exporting to malfunction output module (6) after the failure modes identification.
Malfunction output module (6) is used to export the separate and fault type signal of fault that fault judgement module (5) provides.Malfunction output module (6) has multiple mode signal output, signal output can be modes such as coding output, data bus output, the output of I2C bus, level output at least, and malfunction output module (6) also can carry out the real-time online sound and light alarm to current transformer failure metering.
Power module (7) provides working power for the current transformer failure metering real time on-line detection device, wherein includes supply convertor, voltage stabilizer and backup battery group in the associated components of working power.Power module (7) has power-down protection, in real time the working power of monitoring and metering current mulual inductor malfunction real time on-line detection device.When current transformer failure metering real time on-line detection device externally fed power supply dead electricity, power module (7) starts the backup battery group provides working power for current transformer failure metering detects.
In accompanying drawing 2, provided another modular structure block diagram of the present invention.On the basis of the accompanying drawing 1 that the present invention provides, increase clock module (8), malfunction logging modle (9), malfunction display module (10), network communication module (11), be used for another enforcement purpose of technical solution of the present invention.
Clock module (8) is used for providing current time and timing signal to the various modules of time data that need of current transformer failure metering real-time on-line detecting method and device, and clock module (8) has clock check and correction function.
The separate accurate recording that carries out takes place to the zero-time of current transformer failure metering and concluding time, failure mode, fault in malfunction logging modle (9) under the common control of fault judgement module (5), clock module (8); All data of malfunction logging modle (9) all have password and power-down protection, include fault zero-time and concluding time, failure mode in every record data content at least, data messages such as separate take place fault.Malfunction logging modle (9) also can write down the operational factor of metering current mulual inductor; as master datas such as set-up time, calibration interval, current transformer device numbering, metering method, transformer ratios, the operational factor record has password and power-down protection equally.The data recording of malfunction logging modle (9) can be exported to malfunction display module (10) as required, or exports to network communication module (11).
Malfunction display module (10) comprises Chinese character base and Chinese character LCD, malfunction display module (10) is subjected to the common control of clock module (8) and malfunction logging modle (9), but the current dynamic time data that read clock module (8) provides, and show data such as fault data in the malfunction logging modle (9), operational factor.
The output interface of network communication module (11) includes RS232 interface and RS485 interface, with Surveillance center of management of power use department computing machine, be that host computer carries out connected network communication, its connected network communication mode can be the direct and host computer networkings of modes such as power carrier, cable transmission, optical cable transmission, far infrared transmission, wireless transmission, forms the connected network communication network.The connected network communication mode can also be passed through other communication systems, networks with host computer indirectly as power load supervisory system, Automatic meter reading system etc., forms the connected network communication network.
The fault record data that network communication module (11) provides malfunction logging modle (9), by the connected network communication network, communication protocol according to the rules, when metering current mulual inductor breaks down, in time send failure message to intra-office Surveillance center computing machine, current transformer failure metering is realized real-time, Rapid Alarm, the various data recording of while in host computer transmission malfunction logging modle (9), and can receive the host computer instruction, revise the operational factor in the malfunction logging modle (9), and clock module (8) is carried out the clock check and correction.
Current transformer failure metering real-time on-line detecting method provided by the invention and device, compare with existing metering current mulual inductor detection method and device, can solve effectively that other relevant measurement instrument breaks down in electric energy metrical, and line voltage have or not size variation with load current the time to the authenticity and the deterministic influence of current transformer failure metering real-time online testing result.In addition, detection method provided by the invention and device can realize that to current transformer failure metering real-time online detects under the various methods of operation of high and low voltage electric distribution electrical network, both can be used as the function expanding module of other relevant measurement instrument in the electric energy metrical, also can constitute the current transformer failure metering pick-up unit separately.
Claims (8)
1. current transformer failure metering real-time on-line detecting method and device, it is by high frequency pumping module (1), signal coupling module (2), signal sampling module (3), signal processing module (4), fault judgement module (5), malfunction output module (6), power module (7), clock module (8), malfunction logging modle (9), malfunction display module (10), network communication module modules such as (11) is formed, it is characterized in that, high frequency pumping module (1) is used to take place high-frequency excitation signal, and provide high-frequency excitation signal to signal coupling module (2), provide reference signal to signal processing module (4) simultaneously.Signal coupling module (2) links to each other with high frequency pumping module (1), signal sampling module (3), is used to isolate forceful electric power loop and the weak electrical loop of high frequency pumping module (1) and the weak electrical loop of signal sampling module (3) of metering current mulual inductor; The forceful electric power loop that signal coupling module (2) is also exported to metering current mulual inductor with the coupling of the high-frequency excitation signal of high frequency pumping module (1), and the high frequency feedback signal in metering current mulual inductor forceful electric power loop is coupled to signal sampling module (3).The high frequency feedback signal that signal sampling module (3) is used for metering current mulual inductor forceful electric power loop that signal coupling module (2) is provided carries out processing backward signal processing modules (4) such as real-time online signal sampling, amplification, filtering, shaping provides feedback signal.
2. according to described current transformer failure metering real-time on-line detecting method of claim 1 and device, it is characterized in that, signal processing module (4) links to each other with high frequency pumping module (1), signal sampling module (3), the reference signal that high frequency pumping module (1) provides is carried out processing such as analog to digital conversion, and the feedback signal that signal sampling module (3) provides carried out reference signal and feedback signal after handling being delivered to fault judgement module (5) after analog to digital conversion, digital filtering, fourier transform etc. handle.Fault judgement module (5) links to each other with signal processing module (4), signal to signal processing module (4) output carries out analysis and judgement, when metering current mulual inductor breaks down, deliver to malfunction output module (6) automatically to fault type and the separate judgement of classifying, and with judged result.
3. according to described current transformer failure metering real-time on-line detecting method of claim 1 and device, it is characterized in that, malfunction output module (6) links to each other with fault judgement module (5), when metering current mulual inductor breaks down, malfunction output module (6) is exported the current transformer failure metering type and is taken place separate according to standard data format.
4. according to described current transformer failure metering real-time on-line detecting method of claim 1 and device, it is characterized in that, malfunction logging modle (9) links to each other with fault judgement module (5), clock module (8), and clock module (8) is used to provide the current time.When metering current mulual inductor broke down, the beginning and ending time of record trouble, fault type, generation were separate.
5. according to described current transformer failure metering real-time on-line detecting method of claim 1 and device, it is characterized in that, malfunction display module (10), it is made up of Chinese character base and Chinese character LCD two parts, malfunction display module (10) links to each other with malfunction logging modle (9), when fault takes place maybe need consult dependent failure, can Chinese character and digital dual mode demonstration dependent failure.
6. according to described current transformer failure metering real-time on-line detecting method of claim 1 and device, it is characterized in that, network communication module (11) links to each other with clock module (8), malfunction logging modle (9), by network communication module (11), communication protocol according to correlation standard, when metering current mulual inductor breaks down, in time send failure message to intra-office Surveillance center computing machine.
7. according to described current transformer failure metering real-time on-line detecting method of claim 1 and device, it is characterized in that, power module (7) provides working power for the current transformer failure metering real time on-line detection device, include supply convertor, voltage stabilizer and backup battery group in the associated components of working power, when current transformer failure metering real time on-line detection device externally fed power supply dead electricity, power module (7) starts all kinds of faults that the backup battery group detects metering current mulual inductor.
8. according to described current transformer failure metering real-time on-line detecting method of claim 1 and device, it is characterized in that, detection method and device can be realized the real-time online of current transformer failure metering is detected in the high and low voltage electric distribution electrical network, both can be used as the function expanding module of other relevant measurement instrument in the electric energy metrical, also can constitute the current transformer failure metering pick-up unit separately.
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| CN 02119440 CN1414396A (en) | 2002-05-21 | 2002-05-21 | Method and device for real time on line detection of metering current mulual inductor malfunction |
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| CN 02119440 CN1414396A (en) | 2002-05-21 | 2002-05-21 | Method and device for real time on line detection of metering current mulual inductor malfunction |
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN1314972C (en) * | 2004-12-29 | 2007-05-09 | 重庆龙源科技产业发展有限公司 | Current transformer failure metering and electric larceny proof real-time on-line detection method and apparatus |
| CN102608414A (en) * | 2012-03-28 | 2012-07-25 | 山东计保电气有限公司 | Embedded electric energy measuring method and application extension method of high voltage electrical switchgear |
| CN102879630A (en) * | 2012-09-17 | 2013-01-16 | 浙江省电力公司电力科学研究院 | Capacitive voltage transformer failure monitoring instrument |
| CN104635194A (en) * | 2013-11-08 | 2015-05-20 | 中国石油天然气股份有限公司 | Three-phase metering loop online fault monitoring timing device |
| CN104777446A (en) * | 2015-04-09 | 2015-07-15 | 国家电网公司 | On-line fault diagnosis device and method for capacitive current transformer |
| CN106338704A (en) * | 2015-07-14 | 2017-01-18 | 重庆龙源科技产业发展有限公司 | Real-time detection device suitable for failure and electricity larceny prevention of metering current transformer |
| CN106646320A (en) * | 2016-10-09 | 2017-05-10 | 国网江苏省电力公司电力科学研究院 | Electronic current transformer abnormality identification method based on in-station joint measurement |
| CN107861086A (en) * | 2017-12-27 | 2018-03-30 | 北京东方计量测试研究所 | A kind of in-orbit calibration method of current sensor applied to space and device |
| CN108196157A (en) * | 2018-01-29 | 2018-06-22 | 昆明理工大学 | The parameter and failure detector and method of a kind of current sensor module |
| CN110221239A (en) * | 2019-06-28 | 2019-09-10 | 深圳市锐能微科技有限公司 | Three-phase current detection circuit, method and electric energy computation chip |
| CN112327235A (en) * | 2020-09-23 | 2021-02-05 | 广州智光电气技术有限公司 | Current transformer fault detection method and device, electronic equipment and storage medium |
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2002
- 2002-05-21 CN CN 02119440 patent/CN1414396A/en active Pending
Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN1314972C (en) * | 2004-12-29 | 2007-05-09 | 重庆龙源科技产业发展有限公司 | Current transformer failure metering and electric larceny proof real-time on-line detection method and apparatus |
| CN102608414A (en) * | 2012-03-28 | 2012-07-25 | 山东计保电气有限公司 | Embedded electric energy measuring method and application extension method of high voltage electrical switchgear |
| CN102608414B (en) * | 2012-03-28 | 2014-05-07 | 山东计保电气有限公司 | Embedded electric energy measuring method and application extension method of high voltage electrical switchgear |
| CN102879630A (en) * | 2012-09-17 | 2013-01-16 | 浙江省电力公司电力科学研究院 | Capacitive voltage transformer failure monitoring instrument |
| CN104635194B (en) * | 2013-11-08 | 2017-12-05 | 中国石油天然气股份有限公司 | Three-phase metering loop online fault monitoring timing device |
| CN104635194A (en) * | 2013-11-08 | 2015-05-20 | 中国石油天然气股份有限公司 | Three-phase metering loop online fault monitoring timing device |
| CN104777446A (en) * | 2015-04-09 | 2015-07-15 | 国家电网公司 | On-line fault diagnosis device and method for capacitive current transformer |
| CN104777446B (en) * | 2015-04-09 | 2018-06-01 | 国家电网公司 | A kind of capacitive current transformer on-line fault diagnosis device and method |
| CN106338704A (en) * | 2015-07-14 | 2017-01-18 | 重庆龙源科技产业发展有限公司 | Real-time detection device suitable for failure and electricity larceny prevention of metering current transformer |
| CN106646320A (en) * | 2016-10-09 | 2017-05-10 | 国网江苏省电力公司电力科学研究院 | Electronic current transformer abnormality identification method based on in-station joint measurement |
| CN106646320B (en) * | 2016-10-09 | 2019-06-11 | 国网江苏省电力公司电力科学研究院 | Electronic current mutual inductor exception discrimination method based on combined measurement in standing |
| CN107861086A (en) * | 2017-12-27 | 2018-03-30 | 北京东方计量测试研究所 | A kind of in-orbit calibration method of current sensor applied to space and device |
| CN108196157A (en) * | 2018-01-29 | 2018-06-22 | 昆明理工大学 | The parameter and failure detector and method of a kind of current sensor module |
| CN110221239A (en) * | 2019-06-28 | 2019-09-10 | 深圳市锐能微科技有限公司 | Three-phase current detection circuit, method and electric energy computation chip |
| CN112327235A (en) * | 2020-09-23 | 2021-02-05 | 广州智光电气技术有限公司 | Current transformer fault detection method and device, electronic equipment and storage medium |
| CN112327235B (en) * | 2020-09-23 | 2024-08-13 | 广州智光电气技术有限公司 | Current transformer fault detection method and device, electronic equipment and storage medium |
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