CN201845069U - On-line detection device of insulation stage of capacitive equipment of distributed transformer substation - Google Patents
On-line detection device of insulation stage of capacitive equipment of distributed transformer substation Download PDFInfo
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- CN201845069U CN201845069U CN2010205992759U CN201020599275U CN201845069U CN 201845069 U CN201845069 U CN 201845069U CN 2010205992759 U CN2010205992759 U CN 2010205992759U CN 201020599275 U CN201020599275 U CN 201020599275U CN 201845069 U CN201845069 U CN 201845069U
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Abstract
The utility model discloses an on-line detection device of the insulation stage of capacitive equipment of a distributed transformer substation. The on-line detection device comprises a data collector, a data processor and a system controller which are sequentially connected, and is characterized in that the data collector comprises a plurality of signal sensing units, the data processor comprises on-the-spot signal processing units correspondingly connected with the signal sensing units, and the system controller comprises an upper computer, a communication unit and the like. The on-line detection device integrates the on-line detection of a plurality of electrical equipment including a diverter, a transformer bushing, a current transformer, a voltage transformer and the like; the unified communication is adopted, the real-time performance is good, and the anti-jamming capability is strong, the insulation state of the capacitive equipment and that of the diverter can be reflected, and the insulation state is used for guiding the status maintenance of the equipment, so that the safe operation of equipment is ensured.
Description
Technical field
The utility model relates to the capacitive apparatus insulated state on-line detector of a kind of distributed transformer station, this device is used for the online detection of the state of insulation of transformer station's capacitive apparatus and lightning arrester, belongs to the especially online detection range of capacitive apparatus of converting station high voltage electrical apparatus.
Background technology
Capacitive apparatus is important power transmission and transforming equipment, mainly comprises bushing shell for transformer, current transformer (CT) and voltage transformer (VT) (PT).Capacitive apparatus and lightning arrester are the topmost operational outfits of transformer station, thereby have critical role in transformer station, and the insulation fault of these equipment not only influences the safe operation of whole transformer station, also jeopardize the safety of other equipment and the person simultaneously.So, be necessary to detect timely and effectively for the state of insulation of transformer station's capacitive apparatus and lightning arrester.
Because on-the-spot complex electromagnetic environments of transformer station and mains by harmonics, the big multistability of transformer station's insulation of electrical installation on-line measuring device is not high at present, anti-interference not strong, especially because the restriction of sensor technology makes the characteristic quantity data of being extracted have very big error, and in data transmission procedure, how to deliver to undistortedly that data processing unit goes then be the difficult problem how to select communication modes that will face to these faint electric signal that sensor is extracted.Have again, in the ordinary course of things, influencing the aging factor of transformer station's insulation of electrical installation not only has the factor of electricity, heat also to comprise the factor of physical environment, and big more such as the high more insulating material dielectric loss of temperature value under a stable condition, long-term humidity also can make dielectric loss increase significantly simultaneously.Detected equipment surrounding environment all has periodic variation every day in transformer station, the aging action of insulating material also will be subjected to the influence of environment, these factors all can influence the accuracy of apparatus insulated online detection, so transformer station's on-line measuring device is for the detection of ambient temperature and humidity also particularly important.And existing transformer station insulation of electrical installation on-line measuring device is mostly ignored the detection to environment temperature and humidity, thereby certain error will occur when doing fault analysis and diagnosis.
Summary of the invention
The purpose of this utility model is to overcome the deficiencies in the prior art, and a kind of reliable and stable, capacitive apparatus insulated state on-line detector of distributed transformer station that degree of accuracy is high, real-time is good has strong extendability is provided.
The technical scheme that realizes above-mentioned purpose is: this device constitutes (referring to Fig. 1) by the data acquisition unit (1) that connects successively, data processor (2) and system controller (3); Wherein, data acquisition unit (1) is made of the sensing unit, includes lightning arrester Leakage Current sensor (4), bushing shell for transformer Leakage Current sensor (5), CT Leakage Current sensor (6), PT Leakage Current sensor (7) and Temperature Humidity Sensor (8) (referring to Fig. 2); Data processor (2) comprises the on-site signal processing unit (9) that each sensing unit correspondence is connected, and is connected with the industrial computer (11) of system controller (3) by communications interface unit (10).Data acquisition unit is sent into data processor by the various signals of sensor acquisition and is carried out data processing, and data are sent into system controller at last as the foundation that realizes fault diagnosis and state estimation.
Lightning arrester Leakage Current sensor (4) in the technique scheme, bushing shell for transformer Leakage Current sensor (5), CT Leakage Current sensor (6), PT Leakage Current sensor (7) all adopt zero magnetic flux high precision low current sensor (12).What zero magnetic flux high precision low current sensor adopted is the punching structure, can not change the original mode of connection of equipment under test, directly be sleeved on the screen loop, end or ground wire of bushing shell for transformer, current transformer, voltage transformer (VT) and lightning arrester, and install and the corresponding on-site signal processing unit of each sensor nearby, be connected with industrial computer by communication interface again.Adopt this kind zero magnetic flux high precision low current sensor and connected mode is installed and have degree of accuracy height, advantage that antijamming capability is strong.
Above-mentioned on-site signal processing unit (9) set has signal amplification module (13), signal compensation module (14), signal filtering module (15), channel selecting module (16), A/D modular converter (17), slave computer control module (18) and communication module (19) (referring to Fig. 3).The various types of signal that the sensing unit collects must be through the processing of each module of on-site signal processing unit, these processing comprise amplification, compensation and the filtering of signal, again signal is carried out mould/number conversion, at last by communication module the data upload that collects to industrial computer.Through this a series of processing, the higher hamonic wave in can filtered signal suppresses on-the-spot electromagnetic interference (EMI), make collect data accurate and effective more.
Have, above-mentioned on-site signal processing unit (9) is integrated with switch power module (20) again.Switch power module is input as the 220V industrial-frequency alternating current, and exportable 12V and 5V DC level are for each module of on-site signal processing unit provides direct supply.This module and on-site signal processing unit are integrated, and have easy for installationly, save the space, the advantage of stability and high efficiency.
Above-mentioned industrial computer (11) disposes the host computer procedure module (21) that realizes detection and fault diagnosis.This program module can be monitored lightning arrester in real time, bushing shell for transformer, current transformer, the information of voltage transformer (VT) and ambient temperature and humidity, not only calculation medium loss value and electric capacity can also provide historical data pictures such as the curve map of each detection limit, excellent figure, and the data statistics form of equipment is provided.Simultaneously, this module also has insulation diagnosis and warning function, can provide the operation exception early warning according to online detection limit and historical data diagnosing insulation state thereof.
The utlity model has following technique effect.What zero magnetic flux high precision low current sensor adopted is the punching structure, can not change the original mode of connection of equipment under test, directly be sleeved on the screen loop, end or ground wire of bushing shell for transformer, current transformer, voltage transformer (VT) and lightning arrester, and install and the corresponding on-site signal processing unit of each sensor nearby, be connected with industrial computer by communication interface again; The quantity place that sensor is installed then will be decided according to the situation of the on-the-spot check point arrangement of transformer station, simultaneously according to field condition, thermometer screen in position is installed, at thermometer screen the inside erecting stage Temperature Humidity Sensor and on-site signal processing unit thereof, also be connected with industrial computer by communication interface.Industrial computer is then managed each on-site signal processing unit by communication interface, can realize the real time monitoring function, the relevant information of all detection limits is provided, and do data processing and diagnostic function, have apparatus insulated diagnosis and warning function, the information categorization that online detection data and analysis are drawn files simultaneously, user data query function and printing function are provided, also can be configured equipment by industrial computer, new equipment be can expand, and can remote detection, long-range setting and remote maintenance be realized by the excuse of the integrated automation of transformation stations.Particularly by detection to bushing shell for transformer, current transformer, voltage transformer (VT) and lightning arrester Leakage Current, the state of insulation that reflects capacitive apparatus and lightning arrester, for the diagnosis of transformer station electrical equipment malfunction with state estimation provides accurately, the foundation of science, and, guarantee its safe operation with this repair based on condition of component that instructs equipment.
This use is novel to have following technique effect: the data acquisition unit of (1) device adopts zero magnetic flux high precision low current sensor, easy for installation flexibly, have degree of accuracy height, advantage that antijamming capability is strong.What be somebody's turn to do zero magnetic flux high precision low current sensor employing is the punching structure, can arrange situation according to the on-the-spot check point of transformer station, under the situation that does not change the original mode of connection of equipment under test, directly be sleeved on the screen loop, end or ground wire of bushing shell for transformer, current transformer, voltage transformer (VT) and lightning arrester.(2) industrial computer is managed each site disposal unit by communication interface, can realize the real time monitoring function, the relevant information of all detection limits is provided, and do data processing and diagnostic function, have apparatus insulated diagnosis and warning function, the information categorization that online detection data and analysis are drawn files simultaneously, and user data query function and printing function are provided.(3) device can reflect the state of insulation of capacitive apparatus and lightning arrester, for transformer station's insulation of electrical installation fault diagnosis with state estimation provides effectively, the foundation of science, knows the repair based on condition of component of equipment successively, guarantees its safe operation.
Description of drawings
Fig. 1 is the utility model system architecture synoptic diagram
Fig. 2 is the utility model general principles synoptic diagram
Fig. 3 is the utility model capacitive apparatus and lightning arrester Leakage Current testing process principle schematic
Fig. 4 is the utility model calculation medium loss process flow diagram;
Embodiment
Below in conjunction with drawings and Examples the utility model is described in further detail.
As shown in Figure 1, 2, the distributed transformer station of the utility model capacitive apparatus on-line measuring device, by the data acquisition unit 1 that connects successively, data processor 2, system controller 3 is formed.Data acquisition unit 1 is made of the sensing unit, include lightning arrester Leakage Current sensor 4, bushing shell for transformer Leakage Current sensor 5, CT Leakage Current sensor 6, PT Leakage Current sensor 7, Temperature Humidity Sensor 8, data processor 2 comprises the corresponding on-site signal processing unit 9 that is connected with each sensing unit, and is connected with the industrial computer 11 of system controller 3 by communications interface unit 10.
As shown in Figure 3, in the distributed transformer station capacitive apparatus on-line detecting system on-site signal processing unit 9, signal amplification module 13, signal compensation module 14, signal filtering module 15, channel selecting module 16, A/D modular converter 17, slave computer control module 18 and communication module 19 have been gathered.On-site signal processing unit 9 has also been integrated switch power module 20 and has been each in addition
The module centrally connected power supply.The input end of signal amplification module 13 is inserted by the output terminal of zero magnetic flux high precision low current sensor 12, its output terminal then links to each other with the input end of signal compensation module 14, the output terminal of signal compensation module 14 links to each other with the input end of signal filtering module 15, the output terminal of signal filtering module 15 links to each other with the input end of channel selecting module 16, connect A/D modular converter 17 then the signals through rough handlings made analog to digital conversion, again by host computer procedure module 21 according to the data computation dielectric loss after handling.
As shown in Figure 4, calculation medium loss tan δ, start-up system software, check serial ports after the program initialization, do not open as serial ports and then to continue program initialization, normally open until serial ports, selector channel is promptly selected the A of each detected equipment then, B, the C three-phase, start A/D routine call function commencing signal and gather, promptly in one-period, choose some somes acquired signal data, again being uploaded to database after the signal process software algorithm Filtering Processing that collects, database has the function of storage classification, calculate phase differential by call function again, and the calculation medium loss value, result's storage also is presented on the display.
In above-mentioned sensing unit, the lightning arrester Leakage Current sensor 4 in the sensing unit, bushing shell for transformer Leakage Current sensor 5, CT Leakage Current sensor 6, PT Leakage Current sensor 7 all adopt zero magnetic flux high precision low current sensor 12.Sensor adopts the twin-stage Fundamentals of Sensors, and the permalloy of power frequency small-signal current is tested in initial permeability, higher being more suitable for of maximum permeability in relative other common used material of its iron core employing, and its size depends on the sectional area of the ground wire of institute's checkout equipment.Its coil adopts the enameled wire coiling to comprise former limit, secondary, magnetic test coil and compensating coil.Also have inside and outside two-layer shielding box to suppress on-the-spot in addition and disturb, and in shielding box casting epoxy resin and coagulating agent.
In above-mentioned on-site signal processing unit 9, signal amplification module 13, signal compensation module 14 and signal filtering module 15 amplifiers adopt OP27G, have at a high speed and low noise advantage.Because voltage harmonic can detect to dielectric loss and bring error, so the native system filtering circuit adopts low-pass filter circuit filtering higher hamonic wave, 3 subharmonic content can be limited in 1.0%.The signal of exporting from the sensing unit must pass through amplification, compensation and Filtering Processing and just can send into A/D modular converter 17.The chip of A/D modular converter 17 adopts AD8506, and this chip is a low-power consumption, at a high speed, driving voltage is 12 analog to digital converters of 5V, in-40 ℃ of-85 ℃ of scopes, its sample frequency can reach 40kHz.
The work of A/D modular converter 17 realizes by the configuration of slave computer control module 18, slave computer control module 18 single-chip microcomputers adopt the 8051 single-chip microcomputer STC12C5A16S2 of a new generation of macrocrystalline the 6th generation encryption technology, this chip has super low-power consumption, superpower anti-interference, fireballing advantage, the compatible fully tradition 8051 of its instruction code, but the fast 8-12 of speed is doubly.The special-purpose reset circuit of inner integrated MAX810,2 road PWM, 8 tunnel 10 A/D conversions at a high speed are at the on-the-spot strong jamming occasion of transformer station.This single-chip microcomputer frequency of operation can reach 35MHz, can control the A/D sampling very flexibly.
In above-mentioned industrial computer 11, industrial computer is equipped with TIMS transformer station electrical equipment on-line detecting system, RS485 communication interface by PC is patrolled and examined each on-site signal control module, monitor lightning arrester in real time, bushing shell for transformer, current transformer, the information of voltage transformer (VT) and ambient temperature and humidity.This system is calculation medium loss value and electric capacity not only, and historical data pictures such as the curve map of each detection limit, excellent figure can also be provided, and the data statistics form of equipment is provided.This system also has insulation diagnosis and warning function, can provide the operation exception early warning according to online detection limit and historical data diagnosing insulation state thereof.
Information and abnormal alarm information categorization that TIMS transformer station electrical equipment on-line detecting system can draw online detection data and analysis thereof file, and archive data can be preserved more than 5 years.The user can be to these archive data classification inquiries at times.Can give the industrial computer configure printer, support real time data to print and report capability.This system can also can determine when physical interface form and communication protocol design liaison by realizing remote monitoring, long-range setting and remote maintenance with the integrated substation automated interface again.
Illustrate:
Certain transformer station, the capacitive electrical equipment of installation has: 2 of three-phase main-transformers (being 6 of main transformer sleeve pipes), 6 of lightning arresters, each 6 in current transformer and voltage transformer (VT).Now adopt the utility model device that the capacitive apparatus insulated state of this transformer station is carried out online detection.
By punching zero magnetic flux high precision low current sensor, can not change under the situation of the original mode of connection of above equipment under test, directly be sleeved on screen loop, detected equipment end or the ground wire, and install and the corresponding on-site signal processing unit of each sensor nearby, be connected with industrial computer by communication interface again.According to the on-the-spot capacitive electrical equipment of this transformer station quantity is installed, and each capacitive electrical equipment there is a sensor to carry out online detection, 24 current sensors then will be installed altogether.Thermometer screen is installed near main-transformer again,, also is connected with industrial computer by communication interface at thermometer screen the inside erecting stage Temperature Humidity Sensor and on-site signal processing unit thereof.
Start detection, after system finishes initialization and self check, host computer issues communications command, respectively install a certain phase lightning arrester of checkout equipment Leakage Current, bushing shell for transformer Leakage Current, current transformer Leakage Current, voltage transformer (VT) Leakage Current and ambient temperature and humidity more than the utilization, testing result is as shown in table 1.
The online testing result of certain transformer station's capacitive apparatus of table 1
Data have reflected the state of insulation of transformer station's capacitive electrical equipment in the table 1, and the data that detection obtains have been reacted lightning arrester, bushing shell for transformer, current transformer and voltage transformer (VT) and all have been in normal state of insulation.
Claims (5)
1. capacitive apparatus insulated state on-line detector of distributed transformer station, by the data acquisition unit (1) that connects successively, data processor (2) and system controller (3) constitute, it is characterized in that data acquisition unit (1) is made of the sensing unit, include lightning arrester Leakage Current sensor (4), bushing shell for transformer Leakage Current sensor (5), CT Leakage Current sensor (6), PT Leakage Current sensor (7) and Temperature Humidity Sensor (8), data processor (3) comprises the on-site signal processing unit (9) that each sensing unit correspondence is connected, and is connected with the industrial computer (11) of system controller (3) by communications interface unit (10).
2. according to the capacitive apparatus insulated state on-line detector of claims 1 described distributed transformer station, it is characterized in that lightning arrester Leakage Current sensor (4), bushing shell for transformer Leakage Current sensor (5), CT Leakage Current sensor (6), PT Leakage Current sensor (7) all adopt zero magnetic flux high precision low current sensor (12).
3. according to the capacitive apparatus insulated state on-line detector of claims 1 described distributed transformer station, it is characterized in that on-site signal processing unit (9) set has signal amplification module (13), signal compensation module (14), signal filtering module (15), channel selecting module (16), A/D modular converter (17), slave computer control module (18) and communication module (19).
4. according to the capacitive apparatus insulated state on-line detector of claims 1 described distributed transformer station, it is characterized in that on-site signal processing unit (9) is integrated with switch power module (20).
5. according to the capacitive apparatus insulated state on-line detector of claims 1 described distributed transformer station, it is characterized in that industrial computer (11) disposes the host computer procedure module (21) that realizes detection and fault diagnosis.
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| Application Number | Priority Date | Filing Date | Title |
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| CN2010205992759U CN201845069U (en) | 2010-11-10 | 2010-11-10 | On-line detection device of insulation stage of capacitive equipment of distributed transformer substation |
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| CN2010205992759U CN201845069U (en) | 2010-11-10 | 2010-11-10 | On-line detection device of insulation stage of capacitive equipment of distributed transformer substation |
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102628919A (en) * | 2012-04-25 | 2012-08-08 | 上海交通大学 | Transformer bushing insulation state on-line monitoring system |
| CN102650669A (en) * | 2012-05-21 | 2012-08-29 | 安徽省电力公司池州供电公司 | Charged detection device of substation equipment |
| CN103197174A (en) * | 2013-03-12 | 2013-07-10 | 上海市电力公司 | All-in-one measuring device of energy-storage and grid-connected system |
| CN103234584A (en) * | 2013-04-27 | 2013-08-07 | 中国南方电网有限责任公司超高压输电公司检修试验中心 | SF6 insulation direct-current casing pipe fault diagnosis system and SF6 insulation direct-current casing pipe fault diagnosis method |
| CN103308836A (en) * | 2013-05-27 | 2013-09-18 | 河南省电力公司鹤壁供电公司 | Method, device and system for monitoring insulating property of electronic transformer |
| CN104977484A (en) * | 2015-05-21 | 2015-10-14 | 安徽凯民电力技术有限公司 | Split insulation monitoring equipment |
| CN105137308A (en) * | 2015-09-22 | 2015-12-09 | 国网山东东营市东营区供电公司 | Electric power equipment insulation integrated online monitoring system |
| CN111505451A (en) * | 2020-04-01 | 2020-08-07 | 云南电网有限责任公司红河供电局 | On-spot online evaluation device of capacitive equipment insulating properties of transformer substation |
| CN113237506A (en) * | 2021-03-31 | 2021-08-10 | 国网四川省电力公司电力科学研究院 | Early warning method and system for high-voltage bushing tap device and storage medium |
| CN114994395A (en) * | 2022-08-05 | 2022-09-02 | 成都国佳电气工程有限公司 | Passive railway high-voltage cable related current detection device |
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- 2010-11-10 CN CN2010205992759U patent/CN201845069U/en not_active Expired - Fee Related
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102628919A (en) * | 2012-04-25 | 2012-08-08 | 上海交通大学 | Transformer bushing insulation state on-line monitoring system |
| CN102650669A (en) * | 2012-05-21 | 2012-08-29 | 安徽省电力公司池州供电公司 | Charged detection device of substation equipment |
| CN103197174A (en) * | 2013-03-12 | 2013-07-10 | 上海市电力公司 | All-in-one measuring device of energy-storage and grid-connected system |
| CN103234584B (en) * | 2013-04-27 | 2015-09-16 | 中国南方电网有限责任公司超高压输电公司检修试验中心 | A kind of SF 6isolated dc sleeve pipe fault diagnosis system and diagnostic method |
| CN103234584A (en) * | 2013-04-27 | 2013-08-07 | 中国南方电网有限责任公司超高压输电公司检修试验中心 | SF6 insulation direct-current casing pipe fault diagnosis system and SF6 insulation direct-current casing pipe fault diagnosis method |
| CN103308836A (en) * | 2013-05-27 | 2013-09-18 | 河南省电力公司鹤壁供电公司 | Method, device and system for monitoring insulating property of electronic transformer |
| CN103308836B (en) * | 2013-05-27 | 2015-08-12 | 国家电网公司 | To the methods, devices and systems that the insulating property of electronic mutual inductor are monitored |
| CN104977484A (en) * | 2015-05-21 | 2015-10-14 | 安徽凯民电力技术有限公司 | Split insulation monitoring equipment |
| CN105137308A (en) * | 2015-09-22 | 2015-12-09 | 国网山东东营市东营区供电公司 | Electric power equipment insulation integrated online monitoring system |
| CN111505451A (en) * | 2020-04-01 | 2020-08-07 | 云南电网有限责任公司红河供电局 | On-spot online evaluation device of capacitive equipment insulating properties of transformer substation |
| CN113237506A (en) * | 2021-03-31 | 2021-08-10 | 国网四川省电力公司电力科学研究院 | Early warning method and system for high-voltage bushing tap device and storage medium |
| CN114994395A (en) * | 2022-08-05 | 2022-09-02 | 成都国佳电气工程有限公司 | Passive railway high-voltage cable related current detection device |
| CN114994395B (en) * | 2022-08-05 | 2022-12-06 | 成都国佳电气工程有限公司 | Passive railway high-voltage cable related current detection device |
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