CN2718593Y - Electric cable local discharge on-line monitoring apparatus - Google Patents
Electric cable local discharge on-line monitoring apparatus Download PDFInfo
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- CN2718593Y CN2718593Y CN 200420041922 CN200420041922U CN2718593Y CN 2718593 Y CN2718593 Y CN 2718593Y CN 200420041922 CN200420041922 CN 200420041922 CN 200420041922 U CN200420041922 U CN 200420041922U CN 2718593 Y CN2718593 Y CN 2718593Y
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Abstract
The utility model discloses an electric cable local discharge on-line monitoring device, comprising a Rocchelle's coil local discharge sensor, a front end amplifier, a signal cable, a rear end signal conditioner, a resistance-type potential divider, a data collecting card, a digital IO card and a computer. The electric cable local discharge on-line monitoring device can analyze the discharge parameter of maximal discharging quantity, average discharging quantity, discharging frequency, discharging phase, degree of skewness and kurtosis. The electric cable local discharge on-line monitoring device is provided with the function of abundant spectrogram display, and can display the spectrogram of discharging quantity(containing the maximal discharging quantity and the average discharging quantity) and discharging phase, the spectrogram of discharging frequency and discharging phase, the discharging ellipse spectrogram and the three-dimensional spectrogram of discharging quantity, discharging frequency and discharging phase. The utility model realizes the administration of data by ORACLE, and is provided with the functions of history querying, report printing, thresholding alarming and remote querying.
Description
Technical field
The utility model belongs to power equipment on-line monitoring technique field, relates to a kind of power cable local discharge on-line monitoring device.
Background technology
High-tension cable is the important component part of electric system.Along with the development of high pressure and extra high voltage network, power cable is because its distinctive technological merit has obtained application more and more widely.Cable is in operational process, and internal field's stress that can cause owing to the factors such as accumulation of space charge under inner impurity, semiconductor layer projection, the voltage effect is concentrated, and produces shelf depreciation, and the safe operation of cable is affected.Therefore, by the shelf depreciation of detection streamer insulation, can judge the aging conditions of cable insulation effectively, this is significant for power cable line operation steady in a long-term.
The power equipment local discharge detection device of development is a lot of both at home and abroad, mainly contain pick-up unit, the local discharge detection device that is applied to generator that is applied to the GIS high-frequency local discharging, the high-frequency local discharging pick-up unit that is applied to transformer, but the device that can be applied to online detection power cable shelf depreciation is not seen relevant report.The mancarried device of the detection streamer discharge that Chinese patent publication number 1046045 is introduced, this device adopts the probe coupling technique, in testing process, need artificial mobile probe, be difficult to detect buried in underground cable and the inaccessiable cable of personnel operational site.
Along with the raising of power automation level, operation power partly requires the power equipment monitoring device to have rich data analytic function, powerful data managing capacity and automatization level.The analytical parameters of the partial discharge monitoring device of existing power equipment is few, often can only analyze discharge capacity, discharge time, and the relation between they and the discharge phase waits some basic shelf depreciation parameters, do not have to analyze measure of skewness and kurtosis with the very big shelf depreciation of power equipment insulation ag(e)ing correlativity.And existing discharge monitoring device function is simpler, and relatively poor to a large amount of Monitoring Data managerial abilities, automatization level is not high, is difficult to satisfy the requirement of the growing power department of automatization level.
Summary of the invention
At an urgent demand of on-line monitoring power cable insulation situation, the purpose of this utility model is, a kind of device of on-line monitoring power cable shelf depreciation is provided, and can monitor the shelf depreciation of cable insulation and cable connecting box.
Along with the develop rapidly of computer technology and electronic technology, advanced the fast development of virtual instrument technique.This technology adopts software directly to control bottom hardware, and the collection, analyzing and processing and the result that are finished signal by software show, have realized the theory of " software is exactly instrument ", have advantages such as efficient, easy-to-use, flexible, powerful.
The utility model adopts design of Virtual Instrument thought, developed a kind of device of on-line monitoring power cable shelf depreciation, this device can be analyzed maximum pd quantity, average discharge capacity, discharge time, discharge phase, measure of skewness, discharge parameters such as kurtosis, has abundant spectrogram Presentation Function, can show discharge capacity (comprising maximum pd quantity and average discharge capacity) and discharge phase spectrogram, discharge time and discharge phase spectrogram, oval spectrogram discharges, discharge capacity-discharge time-discharge phase three-dimensional spectrum, realize the management of data by ORACLE, have the historical query function, also have report printing, Threshold Alerts, functions such as remote inquiry.
The technical solution that realizes above-mentioned purpose is that a kind of coaxial shielding cable that adopts carries out the effectively power cable local discharge on-line monitoring device of transmission of signal, is characterized in that this device comprises:
The Luo-coil local discharge sensor of socket three-phase on the cable grounding line is used to gather the power cable local discharge signal;
One data acquisition circuit, data acquisition circuit is provided with front-end amplifier, back end signal conditioner, resitstance voltage divider;
Front-end amplifier is used for the signal of Luo-coil local discharge sensor is amplified, and has enough amplitudes when making signal arrive the back end signal conditioner through long-distance transmissions;
The back end signal conditioner is installed in Control Room, is used for local discharge signal is carried out program control amplification, filtering, multichannel selection, Signal Spacing, also can carry out Signal Spacing to the output signal of resitstance voltage divider;
Resitstance voltage divider is installed in transformer substation voltage mutual inductor low-voltage output, gathers simultaneously with local discharge signal, is used for dividing potential drop from the voltage transformer (VT), obtains on-the-spot voltage signal, as the phase reference information of analyzing discharge signal;
One computing machine is used to analyze the maximum pd quantity of discharge signal, average discharge capacity, discharge time, measure of skewness and kurtosis; Data collecting card, I/O card, pretreatment module, discharge signal characteristics analysis module, insulation trend prediction module, threshold values judge module and alarm module are arranged in the computing machine;
Data collecting card is used to receive the signal of resitstance voltage divider and back end signal conditioner, send in the pretreatment module, through pretreated data transmission in the discharge signal characteristics analysis module, the discharge signal characteristics analysis module one the tunnel is sent into insulation trend prediction module after treatment, insulation trend prediction module also realizes remote monitoring by web server software, another road is sent in the threshold values judge module, and the threshold values judge module is reported to the police according to signal; The I/O card is used for and front-end amplifier, the communication of back end signal conditioner.
Some other characteristics of the present utility model are, the frequency range of described Luo-coil local discharge sensor is 50kHz～20MHz, and it is made of external shield box, magnetic core, coil, integrating resistor, output coaxial cable plug; Wherein magnetic core is annular nickel zinc magnetic core, and concrete size depends on the ground wire sectional area of the cable of monitoring.
Described annular nickel zinc magnetic core is for the cable of 35kV～500kV, and internal diameter is 30mm～45mm; Described coil adopts the enameled wire coiling, and the number of turn is 17 circles; The impedance phase of described integrating resistor and output coaxial cable plug is 50 Ω together, launches in transmission course to prevent local discharge signal.
The frequency band range of described front-end amplifier is 50kHz～20MHz, coincide with Luo-coil local discharge sensor working band.
Described resitstance voltage divider is selected powerful resistance polyphone dividing potential drop for use, and resistance is respectively 500k Ω and 2.5k Ω, and power is 4W.
Described back end signal conditioner has the bandpass filtering modules block of 50kHz～20MHz, to reduce the undesired signal that discharge signal may be introduced through long Distance Transmission the time.
The highest real-time sampling speed of described data collecting card is 100MS/s, and analog bandwidth is 20MHz, 8 of A/D resolution, and input voltage range-25V～+ 25V.
Described digital collection jig has three ports, and 8 of each ports are formed a control word, can write control word on each port and realize control function; By this digital collection card control passage gating, gain-adjusted and filtration module.
Power cable local discharge on-line monitoring device of the present utility model, adopt design of Virtual Instrument thought, by computing machine discharge signal is adopted statistical analysis technique, analyze the maximum pd quantity of discharge signal, average discharge capacity, discharge time, measure of skewness, kurtosis, can show discharge capacity (comprising maximum pd quantity and average discharge capacity) and discharge phase spectrogram, discharge time and discharge phase spectrogram, oval spectrogram discharges, discharge capacity-discharge time-discharge phase three-dimensional spectrum, realize the management of data by the ORACLE database, have the inquiry of historical data function, also have report printing simultaneously, functions such as Threshold Alerts.Web server software has been installed on computers, and the long-distance user can utilize Internet Explorer, by in the set IP address access means of the utility model, to check current monitoring result and enquiry of historical data.
Description of drawings
Fig. 1 is a composition structural representation of the present invention;
Fig. 2 is the cell winding synoptic diagram;
Fig. 3 is resitstance voltage divider structural representation (wherein R1 is 500k Ω, and R2 is 2.5k Ω);
Fig. 4 is the amplifying circuit schematic diagram of front-end amplifier;
Fig. 5 is the filtering circuit schematic diagram (wherein u1 is a signal input part, and u2 is a signal output part) of back end signal conditioner;
Fig. 6 is the structured flowchart of data collecting card.
Embodiment
Below in conjunction with accompanying drawing the utility model is described in further detail.
According to technique scheme, power cable local discharge on-line monitoring device of the present utility model adopts the coaxial shielding cable to carry out signal and effectively transmits, and this device comprises:
The Luo-coil local discharge sensor 1 of socket three-phase on the cable grounding line is used to gather the power cable local discharge signal;
One data acquisition circuit 2, data acquisition circuit 2 is provided with front-end amplifier 21, back end signal conditioner 22, resitstance voltage divider 23;
Front-end amplifier 21 amplifies in the signal with Luo-coil local discharge sensor 1, has enough amplitudes when making signal arrive back end signal conditioner 22 through long-distance transmissions;
Back end signal conditioner 22 is installed in Control Room, is used for local discharge signal is carried out program control amplification, filtering, multichannel selection, Signal Spacing, also can carry out Signal Spacing to the output signal of resitstance voltage divider;
One computing machine 3 is used to analyze the maximum pd quantity of discharge signal, average discharge capacity, discharge time, measure of skewness and kurtosis; Data collecting card 31, I/O card 32, pretreatment module 33, discharge signal characteristics analysis module 34, insulation trend prediction module 35, threshold values judge module 36 and alarm module 37 are arranged in the computing machine 3;
Data collecting card 31 is used to receive the signal of resitstance voltage divider 23 and back end signal conditioner 22, send in the pretreatment module 33, through pretreated data transmission in discharge signal characteristics analysis module 34, discharge signal characteristics analysis module 34 one the tunnel is sent into insulation trend prediction module 35 after treatment, insulation trend prediction module 35 also realizes remote monitoring by web server software, another road is sent in the threshold values judge module 36, and threshold values judge module 36 is reported to the police according to signal; I/O card 32 is used for and front-end amplifier 21,22 communications of back end signal conditioner.
The discharge signal that is socketed in local discharge sensor 1 coupling on the cable grounding line is through after 21 amplifications of the front-end amplifier on the circuit board 2, be transferred to through signal cable after the processing such as the back end signal conditioner 22 that is positioned at Control Room amplifies, filtering, Signal Spacing, multichannel selection, be sent to the data collecting cards that are installed in the computing machine 3 and carry out data acquisition, processing and result's demonstration.Resitstance voltage divider is installed in transformer substation voltage mutual inductor low-voltage output, its output signal is sent into the back end signal conditioner after through signal cable transmission and processing such as is isolated, gather simultaneously with local discharge signal, be used to obtain the phase reference information of cable local discharge.
Luo-coil local discharge sensor 1 is made of external shield box, magnetic core, coil, integrating resistor, output coaxial cable plug.Wherein magnetic core is annular nickel zinc magnetic core, and concrete size depends on the ground wire sectional area of the cable of monitoring, and the general magnetic core internal diameter that uses for the cable of 35kV～500kV is 30～45mm.Coil adopts the enameled wire coiling, and the number of turn is 17 circles.Integrating resistor is 50 Ω, and the characteristic impedance of output BNC connector also is 50 Ω, and the characteristic impedance of their resistance and signal cable equates, prevents that local discharge signal from launching in transmission course.The frequency range of the sensor that the utility model uses is 50kHz～20MHz.The Luo-coil local discharge sensor is an annular, is socketed in cable grounding line coupling cable discharge signal, does not influence the normal operation of cable.
Front-end amplifier 21 is installed near the Luo-coil local discharge sensor 1, local discharge signal to the output of Luo-coil local discharge sensor amplifies, has big amplitude when making signal arrive back end signal conditioning unit, to improve anti-interference level through long-distance transmissions.The frequency band range of the amplifier that the utility model adopted is 50kHz～20MHz, coincide with the working sensor frequency band.
Because the distance of cable grounding linear distance Control Room is generally distant, in order to guarantee effectively transmission and anti-interference in transmission course of discharge signal, native system has selected for use the coaxial shielding cable to carry out the distant signal transmission.
Resitstance voltage divider is used for dividing potential drop from the voltage transformer (VT), obtains voltage signal, as the phase reference information of analyzing discharge signal.Resitstance voltage divider has A, B, C three-phase, respectively corresponding the A of cable, B, C three-phase.Resitstance voltage divider select powerful resistance polyphone dividing potential drop for use, resistance is respectively 500k Ω and 2.5k Ω, power all is 4W.
The back end signal conditioner is installed in Control Room, can carry out program control amplification, filtering, multichannel selection, Signal Spacing to local discharge signal, also can carry out Signal Spacing to the output signal of resitstance voltage divider.Program control amplification that this device has or attenuation multiple have 1,2,5,10,20,50,100 times, select suitable enlargement factor, and discharge signal is nursed one's health analog input card optimum signal input range, the quantization error when changing to reduce capture card A/D.This device has the bandpass filtering modules block of 50kHz～20MHz, to reduce the undesired signal that discharge signal may be introduced through long Distance Transmission the time.This device has the multichannel selection function, because it has a plurality of signal input parts, comprise the discharge signal of many cables and the phase reference voltage signal of resitstance voltage divider output, when each the detection, need select one road discharge signal and one road phase reference voltage signal to handle, need carry out multichannel and select.
The highest real-time sampling speed of the data collecting card that is adopted is 100MS/s, and analog bandwidth is 20MHz, 8 of A/D resolution, and input voltage range-25V～+ 25V.The sample frequency of this card is 5 times of discharge signal highest frequency, can gather the discharge signal of input without distortion.This jig has the two-way input end of analog signal, can gather discharge signal and voltage reference signal simultaneously.
The digital collection jig that is adopted has three ports, and 8 of each ports are formed a control word, can write control word on each port and realize control function.By this digital collection card control passage gating, gain-adjusted and filtration module.
Analog input card and and computing machine make up the collection and the analysis platform of device, have characteristics such as friendly interface, analytic function are strong.Can be used in the local discharge signal of on-line monitoring power cable, frequency range is 50kHz～20MHz, adopt statistical analysis technique, can analyze maximum pd quantity, average discharge capacity, discharge time, measure of skewness, the statistical parameter of shelf depreciations such as kurtosis, the spectrogram that can show maximum pd quantity and average discharge capacity and discharge phase, discharge time and discharge phase spectrogram, oval spectrogram discharges, discharge capacity-discharge time-discharge phase three-dimensional spectrum, realize the management of data by the ORACLE database, have the inquiry of historical data function, also have report printing simultaneously, Threshold Alerts, functions such as remote inquiry.Finished a model machine according to the technique scheme applicant, reached the purpose of this utility model through evidence.
Claims (8)
1. one kind is adopted the coaxial shielding cable to carry out the effectively power cable local discharge on-line monitoring device of transmission of signal, it is characterized in that this device comprises:
One Luo-coil local discharge sensor (1), this Luo-coil local discharge sensor (1) socket three-phase is on the cable grounding line;
One data acquisition circuit (2), data acquisition circuit (2) is provided with front-end amplifier (21), back end signal conditioner (22), resitstance voltage divider (23); Resitstance voltage divider (23) is installed in transformer substation voltage mutual inductor low-voltage output, and back end signal conditioner (22) is installed in Control Room;
Front-end amplifier (21) amplifies the signal of Luo-coil local discharge sensor (1), is transferred in the back end signal conditioner (22);
One computing machine (3); Data collecting card (31), I/O card (32), pretreatment module (33), discharge signal characteristics analysis module (34), insulation trend prediction module (35), threshold values judge module (36) and alarm module (37) are arranged in this computing machine (3);
Data collecting card (31) is with the resitstance voltage divider (23) of reception and the signal of back end signal conditioner (22), send in the pretreatment module (33), arrive in the discharge signal characteristics analysis module (34) through pretreated data transmission, discharge signal characteristics analysis module (34) the one tunnel is sent into insulation trend prediction module (35) after treatment, insulation trend prediction module (35) also realizes remote monitoring by web server software, another road is sent in the threshold values judge module (36), and threshold values judge module (36) is reported to the police according to signal; I/O card (32) and front-end amplifier (21), back end signal conditioner (22) communication.
2. power cable local discharge on-line monitoring device as claimed in claim 1, it is characterized in that, the frequency range of described Luo-coil local discharge sensor (1) is 50kHz～20MHz, and it is made of external shield box, magnetic core, coil, integrating resistor, output coaxial cable plug; Wherein magnetic core is annular nickel zinc magnetic core, and concrete size depends on the ground wire sectional area of the cable of monitoring.
3. power cable local discharge on-line monitoring device as claimed in claim 2 is characterized in that, described annular nickel zinc magnetic core is for the cable of 35kV～500kV, and internal diameter is 30mm～45mm; Described coil adopts the enameled wire coiling, and the number of turn is 17 circles; The impedance of described integrating resistor and output coaxial cable plug is 50 Ω.
4. power cable local discharge on-line monitoring device as claimed in claim 1 is characterized in that, the frequency band range of described front-end amplifier (21) is 50kHz～20MHz, coincide with Luo-coil local discharge sensor (1) working band.
5. power cable local discharge on-line monitoring device as claimed in claim 1 is characterized in that, described resitstance voltage divider (23) is selected powerful resistance polyphone dividing potential drop for use, and resistance is respectively 500k Ω and 2.5k Ω, and power is 4W.
6. power cable local discharge on-line monitoring device as claimed in claim 1 is characterized in that, described back end signal conditioner (22) has the bandpass filtering modules block of 50kHz～20MHz.
7. power cable local discharge on-line monitoring device as claimed in claim 1 is characterized in that, the highest real-time sampling speed of described data collecting card (31) is 100MS/s, and analog bandwidth is 20MHz, 8 of A/D resolution, and input voltage range-25V～+ 25V.
8. as claim 1 or 7 described power cable local discharge on-line monitoring devices, it is characterized in that described digital collection card (31) has three ports, 8 of each ports are formed a control word.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200420041922 CN2718593Y (en) | 2004-05-17 | 2004-05-17 | Electric cable local discharge on-line monitoring apparatus |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200420041922 CN2718593Y (en) | 2004-05-17 | 2004-05-17 | Electric cable local discharge on-line monitoring apparatus |
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| CN2718593Y true CN2718593Y (en) | 2005-08-17 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN 200420041922 Expired - Fee Related CN2718593Y (en) | 2004-05-17 | 2004-05-17 | Electric cable local discharge on-line monitoring apparatus |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102116824A (en) * | 2010-11-30 | 2011-07-06 | 国网电力科学研究院 | Distributed local discharge on-line monitoring method and device for high voltage cable system |
| 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 |
| CN101606074B (en) * | 2007-02-08 | 2012-11-14 | 特英普科技股份责任有限公司 | A method for processing data pertaining to an activity of partial electrical discharges |
| CN103513169A (en) * | 2013-10-18 | 2014-01-15 | 国网上海市电力公司 | High voltage cable partial discharge detection method |
| CN104459483A (en) * | 2014-11-10 | 2015-03-25 | 国网甘肃省电力公司刘家峡水电厂 | 330 kV power cable line partial discharge monitoring method and device |
| CN105676077A (en) * | 2014-11-18 | 2016-06-15 | 北京兴迪仪器有限责任公司 | High-voltage cable partial discharge on-line monitoring alarm method, device and system |
| CN103558810B (en) * | 2006-03-16 | 2016-08-10 | 功率监视器公司 | Underground monitoring system and method |
| CN112014627A (en) * | 2020-08-28 | 2020-12-01 | 陕西斯达防爆安全科技股份有限公司 | Feed detection device with strength feedback and working method |
| CN112684311A (en) * | 2021-01-30 | 2021-04-20 | 国网上海市电力公司 | Characteristic quantity extraction method for identifying oil paper insulation partial discharge type of transformer |
-
2004
- 2004-05-17 CN CN 200420041922 patent/CN2718593Y/en not_active Expired - Fee Related
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103558810B (en) * | 2006-03-16 | 2016-08-10 | 功率监视器公司 | Underground monitoring system and method |
| CN101606074B (en) * | 2007-02-08 | 2012-11-14 | 特英普科技股份责任有限公司 | A method for processing data pertaining to an activity of partial electrical discharges |
| CN102116824A (en) * | 2010-11-30 | 2011-07-06 | 国网电力科学研究院 | Distributed local discharge on-line monitoring method and device for high voltage cable system |
| 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 |
| CN103513169A (en) * | 2013-10-18 | 2014-01-15 | 国网上海市电力公司 | High voltage cable partial discharge detection method |
| CN104459483A (en) * | 2014-11-10 | 2015-03-25 | 国网甘肃省电力公司刘家峡水电厂 | 330 kV power cable line partial discharge monitoring method and device |
| CN105676077A (en) * | 2014-11-18 | 2016-06-15 | 北京兴迪仪器有限责任公司 | High-voltage cable partial discharge on-line monitoring alarm method, device and system |
| CN112014627A (en) * | 2020-08-28 | 2020-12-01 | 陕西斯达防爆安全科技股份有限公司 | Feed detection device with strength feedback and working method |
| CN112684311A (en) * | 2021-01-30 | 2021-04-20 | 国网上海市电力公司 | Characteristic quantity extraction method for identifying oil paper insulation partial discharge type of transformer |
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| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20050817 Termination date: 20130517 |