CN102116824A - Distributed local discharge on-line monitoring method and device for high voltage cable system - Google Patents

Distributed local discharge on-line monitoring method and device for high voltage cable system Download PDF

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Publication number
CN102116824A
CN102116824A CN2010105664744A CN201010566474A CN102116824A CN 102116824 A CN102116824 A CN 102116824A CN 2010105664744 A CN2010105664744 A CN 2010105664744A CN 201010566474 A CN201010566474 A CN 201010566474A CN 102116824 A CN102116824 A CN 102116824A
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CN
China
Prior art keywords
signal
cable
sensor
discharge
local discharge
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CN2010105664744A
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Chinese (zh)
Inventor
罗俊华
李文杰
赵健康
蒙绍新
夏荣
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国网电力科学研究院
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Priority to CN2010105664744A priority Critical patent/CN102116824A/en
Publication of CN102116824A publication Critical patent/CN102116824A/en

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Abstract

The invention provides a distributed local discharge on-line monitoring method and a distributed local discharge on-line monitoring device for a high voltage cable system. A high-frequency broadband electromagnetic coupling sensor is arranged on each accessory of an entire cable line; the sensors are sleeved on grounding lines or crossed and interconnected lines of the cable accessories for coupling a local discharge signal; a 50Hz current sensor is sleeved on a cable body for coupling a power frequency current signal; a lower computer is used for conditioning a sensor signal, acquiring the sensor signal at a high speed and preprocessing the sensor signal; and a digital signal is transmitted to upper computer monitoring software through an optical fiber transmission network; thus on-line monitoring of distributed local discharge of high voltage cable equipment is realized. The method and the device have the advantage that: the on-line monitoring of the local discharge can be realized by performing distributed synchronous high-speed sampling on three-phase accessories of a high voltage cable according to field requirements.

Description

Distributed partial discharge monitoring method of HV CABLE SYSTEM and device

Technical field

The present invention relates to a kind of cable machinery pick-up unit, particularly relate to the distributed partial discharge monitoring method and apparatus of a kind of HV CABLE SYSTEM.

Background technology

Development and application along with high pressure and ultrahigh voltage power cable, crosslinked polyethylene (XLPE) power cable lays simple, few, the safe and reliable characteristics of operation maintenance work with its rational technology and structure, good electric property, installation, has obtained application more and more widely in electric system.The high-voltage and ultra-high cable system has occupied important status as the important step of urban electricity supply and main grid structure in China's urban distribution network.How realizing the state-detection of these cable machineries, guarantee the cable machinery safe and reliable operation, is the focus of studying both at home and abroad at present.Potential faults can be in time found in the online detection of cable system shelf depreciation, and insulation degradation is carried out forecast in early stage and assessment, actively effectively prevents cable system burst operation troubles, is to realize the vital technological means of cable machinery repair based on condition of component.

Cable accessory for example intermediate head all is artificial fabrication and installation under the condition at the scene, and its insulation quality often is lower than cable body insulation quality, be the weak link that insulate in the cable system.The various constructional deficiencies of the bad formation of intermediate head construction technology make joint internal electric field skewness, cause the generation of shelf depreciation.Under power-frequency voltage, shelf depreciation will cause generation and the expansion of electricity tree in the cable insulation, and quicken the deterioration of insulation, finally cause insulation breakdown.

Present many high-tension cable partial discharge monitoring system for field measurement effects are undesirable, its main cause has: (1) extraneous strong-electromagnetic field interference source is a lot, the simple hardware technology that relies on realizes rejecting and preventing that the outside electromagnetic interference difficulty is very big, and the anti-interference method of many software and hardware combining is provided with requirement to some extent to measurement; (2) local discharge signal of Cai Jiing is faint, and amplitude is very little, is very easily flooded by ground unrest; (3) the original waveform distortion of the feasible signal that collects of the amplifier of narrow band filter and high multiple causes erroneous judgement easily; (4) the cable local discharge blipology is not mature enough, lacks the identification judgment technology of partial discharge pulse's signal waveform, frequency and the amplitude of in-site measurement; (5) accumulation of practical operating experiences such as the research of the evaluation basic theory of shortage XLPE cable insulation degradation and running status criterion.

The existence of above-mentioned various factors greatly reduces sensitivity, accuracy, the confidence level of the online detection of high-tension cable shelf depreciation.Therefore, how to use existing advanced technology, suppress to disturb to greatest extent, accurate extraction office discharge signal, more reliable, more delicately for follow-up insulation diagnosis provides information, become the important directions in the online detection of high-tension cable apparatus local discharge.

Summary of the invention

Technical matters to be solved by this invention is: at the online detection the problems referred to above of present cable machinery, the present invention proposes distributed partial discharge monitoring method of a kind of HV CABLE SYSTEM and device thereof, each annex that can distributed monitoring whole piece cable line and the local discharge signal of the body in the annex certain limit.

The technical solution adopted in the present invention is: the distributed partial discharge monitoring method of a kind of HV CABLE SYSTEM, high-frequency wideband electromagnetic coupled sensor is installed at each annex place of whole piece cable line, sensor sleeve is connected on the local discharge signal that is coupled on cable accessory ground wire or the cross interconnected line, the 50Hz current sensor is socketed in the power current signal that is coupled on the cable body, slave computer is nursed one's health sensor signal and high speed acquisition and pre-service, and digital signal is sent to host computer monitoring software by optical fiber transmission network, realize the on-line monitoring of high-tension cable device distribution formula shelf depreciation, it is characterized in that, may further comprise the steps:

(1) socket high-frequency wideband electromagnetic coupled sensor on each cable accessory ground wire of whole piece cable line or cross interconnected line, by inserting behind the signal condition on the passage of high-speed data acquisition card, carry out three-phase synchronous triggering high-speed sampling, and after the FPGA processing of circuit, digital signal is stored among the slave computer ROM;

(2) socket 50Hz power current sensor on cable body by sampling on the passage that also inserts high-speed data acquisition card behind the signal condition, is used for the triggering of local discharge signal acquisition channel, to determine the power-frequency voltage phase place of local discharge signal;

(3) include signal condition module, high-speed data acquisition card, I/O card in the slave computer, be used for finishing preliminary interference inhibition, triggering collection, the data storage of local discharge signal;

(4) optical fiber transmission network is connected to the ipc monitor unit with each slave computer monitoring means;

(5) hardware controls to slave computer is finished in the ipc monitor unit, and the demonstration of the reception of image data, apparent discharge capacity, the discharge spectrogram of discharge capacity-discharge phase show;

(6), form the discharge trend database, thereby grasp whole piece cable line insulation operation conditions by continuous monitoring to each annex discharge capacity.

The present invention also provides a kind of HV CABLE SYSTEM distributed local discharge on-line monitoring device, comprise the high-frequency wideband electromagnetic sensor, optical fiber transmission network and host computer, the high-frequency wideband electromagnetic sensor is socketed on threephase cable annex ground wire or the cross interconnected line, it is characterized in that, also comprise slave computer data pre-service collecting unit, host computer links to each other with slave computer by optical fiber transmission network, slave computer data pre-service collecting unit further comprises the preposition conditioning of signal unit, the I/O control module, high-speed data acquisition card, the preposition conditioning of signal unit is nursed one's health the signal of high-frequency wideband electromagnetic sensor coupling, high-speed data acquisition card is gathered the signal after nursing one's health, the I/O control module is finished the control of collection, and by optical fiber transmission network image data is sent to host computer.

The invention has the beneficial effects as follows: the invention has the advantages that and by high-tension cable three-phase annex being carried out distributed synchronous high-speed sampling, to realize partial discharge monitoring according to on-the-spot needs.The mode of this device wideband high speed acquisition can be obtained complete local discharge signal waveform, can show apparent discharge capacity and various discharge spectrogram in real time.The continuous monitoring of discharge capacity can realize the monitoring to the cable system insulation status, for the state maintenance of cable machinery provides strong technical support.

Description of drawings

Fig. 1 is the principle flow chart of the distributed partial discharge monitoring method of the HV CABLE SYSTEM of the embodiment of the invention.

Fig. 2 is the functional block diagram of the distributed local discharge on-line monitoring device of HV CABLE SYSTEM of the embodiment of the invention.

Embodiment

The present invention is described in further detail below in conjunction with drawings and Examples.

Referring to Figure 1 and Figure 2, the distributed partial discharge monitoring method of HV CABLE SYSTEM that provides for the embodiment of the invention and the principle and the functional block diagram of device.

The distributed local discharge on-line monitoring device of HV CABLE SYSTEM of the present invention, comprise the high-frequency wideband electromagnetic sensor, optical fiber transmission network and host computer, the high-frequency wideband electromagnetic sensor is socketed on threephase cable annex ground wire or the cross interconnected line, it is characterized in that, also comprise slave computer data pre-service collecting unit, host computer links to each other with slave computer by optical fiber transmission network, slave computer data pre-service collecting unit further comprises the preposition conditioning of signal unit, the I/O control module, high-speed data acquisition card, the preposition conditioning of signal unit is nursed one's health the signal of high-frequency wideband electromagnetic sensor coupling, high-speed data acquisition card is gathered the signal after nursing one's health, the I/O control module is finished the control of collection, and by optical fiber transmission network image data is sent to host computer.

The high-frequency wideband electromagnetic sensor is installed on the local discharge signal that is coupled on cable accessory ground wire or the cross interconnected line, and 50Hz power-frequency voltage sensor is installed on the power current signal that is coupled near the body of annex; The pre-service of clutter on the ground wire is finished in the preposition conditioning of local discharge signal unit, and signal condition is carried out high-speed data acquisition to high speed data collecting card input range, and with acquired data storage in jumbo ROM; Optical fiber transmission network is used for slave computer image data high-speed transfer to host computer monitoring software; Host computer is controlled the signal condition collecting unit, receives to carry out Software Anti-interference after the image data and handle, and shows placing TV at discharge capacity, and discharge spectrogram such as q-φ.

Critical piece to described device illustrates one by one below:

(1) high-frequency wideband electromagnetic coupled sensor

The high-frequency wideband signal transducer adopts nickel-zinc ferrite, and frequency range is 20kHz-20MHz, is socketed in during measurement that to form sensor on three-phase annex ground wire or the cross interconnected line right, and the signal of coupling comprises local discharge signal, interference, ground unrest.

50Hz power frequency component sensor is used for the power current signal of coupling cable body, as triggering collection, and the operating frequency phase at definite discharge signal place.

(2) slave computer data pre-service collecting unit

The slave computer unit is installed near the sensor, the signal of sensor output is carried out the hardware filtering partly disturb, and makes follow-up amplifying unit amplify local discharge signal, to improve detection sensitivity.

The program control signal amplifying unit has 1,5,10,20,50,100 times enlargement factor, with the input range of signal condition to data collecting card the best.

The high sampling rate of the data collecting card that is adopted is 60MS/s, and analog bandwidth is 30MHz, and A/D resolution is 12, and the signal storage of high speed acquisition is in ROM.

The I/O control card is used for the transmission of control command between upper and lower computer and receives.

(3) optical fiber transmission network

Adopt the triumphant unjacketed optical fiber of band steel, wherein one as standby.Every optical fiber 16 cores block optical fiber welding and draw one road optical fiber being connected to a slave computer unit in the fibre concentrator of each node.

(4) host computer monitoring software

Upper computer software is used for controlling the slave computer data acquisition, program control signal conditioning unit is set and controls the image data that reception slave computer ROM stores.

After each phase synchronization signal carried out comprehensive anti-interference process, upper computer software extracted local discharge signal, showed shelf depreciation apparent discharge capacity, and discharge spectrogram such as q-φ.

The distributed partial discharge monitoring method of HV CABLE SYSTEM of the present invention, high-frequency wideband electromagnetic coupled sensor is installed at each annex place of whole piece cable line, sensor sleeve is connected on the local discharge signal that is coupled on cable accessory ground wire or the cross interconnected line, and the 50Hz current sensor is socketed in the power current signal that is coupled on the cable body; Slave computer is nursed one's health sensor signal and high speed acquisition and pre-service, and by optical fiber transmission network digital signal is sent to host computer monitoring software, realizes the on-line monitoring of high-tension cable device distribution formula shelf depreciation.May further comprise the steps:

(1) socket high-frequency wideband electromagnetic coupled sensor on each cable accessory ground wire of whole piece cable line or cross interconnected line, by inserting behind the signal condition on the passage of high-speed data acquisition card, carry out three-phase synchronous triggering high-speed sampling, and after FPGA (field programmable gate array) processing of circuit, digital signal is stored among the slave computer ROM (internal memory).

(2) socket 50Hz power current sensor on cable body by sampling on the passage that also inserts high-speed data acquisition card behind the signal condition, is used for the triggering of local discharge signal acquisition channel, to determine the power-frequency voltage phase place of local discharge signal.

(3) include signal condition module, high-speed data acquisition card, I/O card in the slave computer, be used for finishing preliminary interference inhibition, triggering collection, the data storage of local discharge signal.

(4) optical fiber transmission network is connected to the ipc monitor unit with each slave computer monitoring means.

(5) hardware controls to slave computer is finished in the ipc monitor unit, and discharge such as the demonstration of the reception of image data, apparent discharge capacity, q-φ (discharge capacity-discharge phase) spectrogram shows.

(6), form the discharge trend database, thereby grasp whole piece cable line insulation operation conditions by continuous monitoring to each annex discharge capacity.

The distributed partial discharge monitoring of whole piece cable line can carry out forecast in early stage and assessment to insulation degradation, actively effectively prevents cable system burst operation troubles.

Claims (2)

1. distributed partial discharge monitoring method of HV CABLE SYSTEM, high-frequency wideband electromagnetic coupled sensor is installed at each annex place of whole piece cable line, sensor sleeve is connected on the local discharge signal that is coupled on cable accessory ground wire or the cross interconnected line, the 50Hz current sensor is socketed in the power current signal that is coupled on the cable body, slave computer is nursed one's health sensor signal and high speed acquisition and pre-service, and digital signal is sent to host computer monitoring software by optical fiber transmission network, realize the on-line monitoring of high-tension cable device distribution formula shelf depreciation, it is characterized in that, may further comprise the steps:
(1) socket high-frequency wideband electromagnetic coupled sensor on each cable accessory ground wire of whole piece cable line or cross interconnected line, by inserting behind the signal condition on the passage of high-speed data acquisition card, carry out three-phase synchronous triggering high-speed sampling, and after the FPGA processing of circuit, digital signal is stored among the slave computer ROM;
(2) socket 50Hz power current sensor on cable body by sampling on the passage that also inserts high-speed data acquisition card behind the signal condition, is used for the triggering of local discharge signal acquisition channel, to determine the power-frequency voltage phase place of local discharge signal;
(3) include signal condition module, high-speed data acquisition card, I/O card in the slave computer, be used for finishing preliminary interference inhibition, triggering collection, the data storage of local discharge signal;
(4) optical fiber transmission network is connected to the ipc monitor unit with each slave computer monitoring means;
(5) hardware controls to slave computer is finished in the ipc monitor unit, and the demonstration of the reception of image data, apparent discharge capacity, the discharge spectrogram of discharge capacity-discharge phase show;
(6), form the discharge trend database, thereby grasp whole piece cable line insulation operation conditions by continuous monitoring to each annex discharge capacity.
2. distributed local discharge on-line monitoring device of HV CABLE SYSTEM, comprise the high-frequency wideband electromagnetic sensor, optical fiber transmission network and host computer, the high-frequency wideband electromagnetic sensor is socketed on threephase cable annex ground wire or the cross interconnected line, it is characterized in that, also comprise slave computer data pre-service collecting unit, host computer links to each other with slave computer by optical fiber transmission network, slave computer data pre-service collecting unit further comprises the preposition conditioning of signal unit, the I/O control module, high-speed data acquisition card, the preposition conditioning of signal unit is nursed one's health the signal of high-frequency wideband electromagnetic sensor coupling, high-speed data acquisition card is gathered the signal after nursing one's health, the I/O control module is finished the control of collection, and by optical fiber transmission network image data is sent to host computer.
CN2010105664744A 2010-11-30 2010-11-30 Distributed local discharge on-line monitoring method and device for high voltage cable system CN102116824A (en)

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Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102385026A (en) * 2011-11-14 2012-03-21 国网电力科学研究院 On-line positioning method and device for partial discharge of high-voltage cable line
CN102636736A (en) * 2012-05-10 2012-08-15 山东电力集团公司济南供电公司 Online monitoring system for partial discharge of middle-high voltage power cable
CN103048635A (en) * 2012-12-21 2013-04-17 中国电力科学研究院 Anti-interference performance evaluation method for high voltage cable partial discharge on-line monitoring device
CN103424676A (en) * 2013-08-21 2013-12-04 国家电网公司 Online partial discharge monitoring system for cable
CN103487734A (en) * 2013-09-24 2014-01-01 江苏新亚高电压测试设备有限公司 Full-digitalization multi-channel real-time synchronous partial discharge detector
WO2014075584A1 (en) * 2012-11-16 2014-05-22 国家电网公司 Method for in-situ detection of partial discharge of damped oscillation wave of large-length ultrahigh-voltage crosslinked cable
CN104655996A (en) * 2015-02-04 2015-05-27 国家电网公司 Live detection device for partial discharge of GIS cable terminal, and use method of device
CN104834765A (en) * 2014-12-31 2015-08-12 国网电力科学研究院武汉南瑞有限责任公司 Power cable accessory state evaluation method based on finite element electric field analysis
CN104865511A (en) * 2015-06-23 2015-08-26 国家电网公司 Partial discharge detection device
CN104951024A (en) * 2015-07-21 2015-09-30 山东鲁能软件技术有限公司 Big data integrated machine based on electric power application
CN105044579A (en) * 2015-06-05 2015-11-11 北京兴迪仪器有限责任公司 Measurement method for distributed partial discharge
CN106093717A (en) * 2016-05-27 2016-11-09 国网浙江宁海县供电公司 A kind of distribution network cable insulating properties detecting system
CN108872802A (en) * 2017-05-12 2018-11-23 中国石油化工股份有限公司 A kind of cable local discharge distributed monitoring system

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2718593Y (en) * 2004-05-17 2005-08-17 西安交通大学 Electric cable local discharge on-line monitoring apparatus
CN101650406A (en) * 2009-09-18 2010-02-17 国网电力科学研究院武汉南瑞有限责任公司 Local discharge on-line detection method and device of high-voltage cross-linking polythene cable system
CN101655538A (en) * 2009-09-27 2010-02-24 西安博源电气有限公司 Generator local discharge on-line monitoring device and monitoring method thereof
CN202003200U (en) * 2010-11-30 2011-10-05 国网电力科学研究院 Distributed partial discharge on-line monitoring device of high-pressure cable system

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2718593Y (en) * 2004-05-17 2005-08-17 西安交通大学 Electric cable local discharge on-line monitoring apparatus
CN101650406A (en) * 2009-09-18 2010-02-17 国网电力科学研究院武汉南瑞有限责任公司 Local discharge on-line detection method and device of high-voltage cross-linking polythene cable system
CN101655538A (en) * 2009-09-27 2010-02-24 西安博源电气有限公司 Generator local discharge on-line monitoring device and monitoring method thereof
CN202003200U (en) * 2010-11-30 2011-10-05 国网电力科学研究院 Distributed partial discharge on-line monitoring device of high-pressure cable system

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102385026A (en) * 2011-11-14 2012-03-21 国网电力科学研究院 On-line positioning method and device for partial discharge of high-voltage cable line
CN102636736A (en) * 2012-05-10 2012-08-15 山东电力集团公司济南供电公司 Online monitoring system for partial discharge of middle-high voltage power cable
WO2014075584A1 (en) * 2012-11-16 2014-05-22 国家电网公司 Method for in-situ detection of partial discharge of damped oscillation wave of large-length ultrahigh-voltage crosslinked cable
CN103048635B (en) * 2012-12-21 2015-03-18 中国电力科学研究院 Anti-interference performance evaluation method for high voltage cable partial discharge on-line monitoring device
CN103048635A (en) * 2012-12-21 2013-04-17 中国电力科学研究院 Anti-interference performance evaluation method for high voltage cable partial discharge on-line monitoring device
CN103424676A (en) * 2013-08-21 2013-12-04 国家电网公司 Online partial discharge monitoring system for cable
CN103487734A (en) * 2013-09-24 2014-01-01 江苏新亚高电压测试设备有限公司 Full-digitalization multi-channel real-time synchronous partial discharge detector
CN103487734B (en) * 2013-09-24 2016-05-11 江苏新亚高电压测试设备有限公司 The totally digitilized multichannel real-time synchronization of one Partial discharge detector
CN104834765A (en) * 2014-12-31 2015-08-12 国网电力科学研究院武汉南瑞有限责任公司 Power cable accessory state evaluation method based on finite element electric field analysis
CN104655996A (en) * 2015-02-04 2015-05-27 国家电网公司 Live detection device for partial discharge of GIS cable terminal, and use method of device
CN105044579A (en) * 2015-06-05 2015-11-11 北京兴迪仪器有限责任公司 Measurement method for distributed partial discharge
CN104865511A (en) * 2015-06-23 2015-08-26 国家电网公司 Partial discharge detection device
CN104951024A (en) * 2015-07-21 2015-09-30 山东鲁能软件技术有限公司 Big data integrated machine based on electric power application
CN106093717A (en) * 2016-05-27 2016-11-09 国网浙江宁海县供电公司 A kind of distribution network cable insulating properties detecting system
CN108872802A (en) * 2017-05-12 2018-11-23 中国石油化工股份有限公司 A kind of cable local discharge distributed monitoring system

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