CN103513125A - Integrated intelligent diagnosis system and method of above-220KV transformers - Google Patents
Integrated intelligent diagnosis system and method of above-220KV transformers Download PDFInfo
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Abstract
The invention discloses an integrated intelligent diagnosis system and a method of above-220KV transformers. The system comprises an intelligent combined cabinet and an integrated intelligent diagnosis platform, wherein the intelligent combined cabinet comprises an oil gas analysis module, an iron core grounding current monitoring module, a capacitive sleeve pipe monitoring module, a partial discharging monitoring module, a temperature monitoring module and a fan monitoring module, and the intelligent combined cabinet provides relevant monitoring and analysis data of the transformers; the integrated intelligent diagnosis platform comprises a remote background, a station-end platform and a database, and the integrated intelligent diagnosis platform receives the monitoring and analysis data of the intelligent combined cabinet for diagnosis. By means of the system and the method, transformer state monitoring is achieved, a layered distribution type integrated system overcomes defects of an original independent system, and based on a uniform hardware platform, a uniform communication protocol and a uniform background analysis and diagnosis software system, the purpose that operation states and failures of the above-220KV transformers are analyzed and diagnosed through the uniform system platform is truly realized.
Description
Technical field
The present invention relates to a kind of transformer online intelligent diagnosis system and method thereof, especially relate to intelligent integral system and the method thereof of the above transformer inline diagnosis of 220KV level.
Background technology
Substation transformer, is the equipment of important core in whole transformer station, especially the above transformer of 220KV level whole power supply hinge core power-supply unit especially.The above transformer fault pattern of 220KV level is mainly machinery, heat and electric three types, and the internal fault of transformer was mainly divided into three kinds of superheating, discharging fault and humidified insulations.Analyze respectively this three kinds of faults below:
1) transformer is crossed superheating
Cross superheating and be due to thermal stress cause insulation accelerated deteriorated, there is the energy density of medium level.Transformer station's depressor overheating fault is modal internal fault, it is to the safe operation of transformer and caused serious threat serviceable life, during transformer operation, there are open circuit loss, load loss and stray loss etc., these losses are converted into heat, when the heat producing and shed heat balance time, temperature reaches steady state (SS).When thermal value is greater than desired value, and heat dissipation capacity is while being less than desired value, and superheating phenomenon has just occurred.The main cause of transformer overheating fault can be summed up as: what shunting switch loose contact caused is 50%; Multipoint earthing unshakable in one's determination and partial short-circuit or leakage field circulation account for 33%; Wire is overheated and joint is bad or securing member is loosening accounts for 14.4%; Because local stopping up of oil channel causes, local heat radiation is bad accounts for 2.6%.Especially transformer station's depressor impact of load that often withstands shocks, research shows that to compare life loss serious with the power transformer of ad eundem, comparative lifetime loss percentage can reach 1.245.
If thermal stress only causes thermal source place insulating oil, decompose, the characteristic gas producing is mainly CH4, and temperature rising C2H4 in C2H4 ，Qie Sui trouble spot accounts for the ratio average out to 62.5% of total hydrocarbon, is secondly C2H6 and H2, and C2H6 is generally lower than 20% of total hydrocarbon according to statistics.High, middle temperature H2 accounts for below 25% of hydrogen hydrocarbon (H2+C1+C2) total amount, while only having cryogenic overheating, is generally 30% left and right.This is because hydrocarbon gas is with due to temperature rising growth comparatively fast.Cross superheating and generally do not produce C2H2, only serious, just can produce trace when overheated, its maximum level also can not surpass 6% of total hydrocarbon.When relating to solid insulating material, also can produce a large amount of CO, CO2.
2) transformer discharge fault
Discharge fault is the major failure of the caused transformer of the insulation degradation inside of causing under high electric field action, by energy density difference, is divided into different discharge fault types.
The first, arc discharge:
Arc discharge is called again high-energy discharge.Take coil turn, interlayer punctures as common, is secondly wire breaking or the fault mode such as flashover and shunting switch arcing over the ground.Be characterized in aerogenesis sharply, amount is large, especially circle, layer insulation fault, because of absence of aura phenomenon, be generally difficult to prediction, finally with catastrophic discontinuityfailure, comes out.Fault characteristic gases is mainly C2H2 and H2, is secondly a large amount of CH4 and C2H4.Because the development of fault speed is very fast, often gas has little time to be dissolved in oil and is just discharged in gas relay, therefore gas content often has much relations with the position of trouble spot, oily Flow Velocity and trouble duration in oil.General C2H2 accounts for the 20-70% of total hydrocarbon amount.H2 accounts for the 30-90% of hydrogen hydrocarbon amount, and the content of C2H2 is higher than the content of CH4 in most cases.
The second, spark discharge:
Spark discharge is generally low-yield electric discharge.It is a kind of intermittence discharge fault.Often occur in following situation, lead-in wire or sleeve pipe oil conservater are to the loose sleeve pipe of current potential, contact tube electric discharge; Lead-in wire part or the loose contact of iron core grounding sheet, and the electric discharge causing; Shunting switch shift fork electric potential floating and the electric discharge that causes.Fault characteristic gases be take C2H2, H2 as main, and because fault energy is little, general total hydrocarbon content is not high, and proportion is up to 25-90% in total hydrocarbon for the C2H2 dissolving in oil, and the content of C2H4 is less than 20%, H2 and accounts for the more than 30% of hydrogen hydrocarbon total amount.
The 3rd, shelf depreciation:
While containing air gap in transformer oil paper insulation, all low than oil and paper of breakdown field strength because the dielectric coefficient of gas is little, therefore normal and generation shelf depreciation is in operation.During general firm electric discharge, discharge capacity is no more than hundreds of skin storehouse, but bubble-discharge develops into when also there is shelf depreciation in oil, and discharge capacity can reach several thousand to hundreds of thousands skin storehouse, often causes that insulating paper layer damages and develop into gradually major accident.
Shelf depreciation is given the transformer insulated great harm that brings.Damage effect because have: when the bombardment of thermal stress effect, charged corpuscle, shelf depreciation, produce the effect of chemically-reactive substance and the effect of shock wave and radiant rays etc.During transformer generation shelf depreciation, electric discharge place can produce high temperature, accelerates the aging of paper oil insulation material, affects its insulation life; Also chemical reaction can occur, produce the gases such as ozone and nitrogen oxide, these gases play the depressor insulation of corrosive attack ，Gei transformer station to insulating material and bring great harm.When the inner generation of transformer partial discharges fault, the gas composition content in oil is different with the difference of discharge energy density, and general total hydrocarbon amount is not high, principal ingredient is H2, next is C2H4, and H2 accounts for the more than 90% of hydrogen hydrocarbon amount conventionally, and CH4 accounts for the more than 90% of total hydrocarbon amount.When the energy density of shelf depreciation increases, also there will be C2H2, but proportion is generally less than 2% in total hydrocarbon, this is the outstanding feature of distinguishing with electric arc, Spark Discharges.
No matter which kind of electric discharge, as long as relate to the fault of solid material or aging, will produce CO, CO2.
3) the transformer insulated fault of making moist
Water is the formidable enemy of transformer insulated system, and operation power department all stipulates to prevent that moisture and air from entering transformer in all previous transformer accident prevention measure of formulating, to control the water cut in insulating material as far as possible.This is because an oily paper insulation system moisture absorption can make that insulating material degraded is aging, dielectric loss increases, insulation resistance reduces, partial discharge inception voltage also decreases, and finally causes the shortening of the operation life of transformer.In order to improve the electrical strength of insulating material, transformer manufacturer has also all stipulated very strict drying process standard, in insulating paper (plate) water cut of recommendation new product, be limited to 0.5%, generally all be controlled in the scope of 0.1%-0.3%, transformer oil water cut is controlled at below 15 μ L/L.
The 4th, the impact of moisture on transformer security of operation
Due to water be stronger polarity liquid (specific inductive capacity is 81, than oil, paper specific inductive capacity much higher, the moisture containing in transformer, is more easily attracted by forceful electric power place.The increase of water cut can cause the decline of dielectric strength.The disruptive strength of oil and dielectric surface is reduced greatly, the safe operation of transformer is caused to great harm.In DL/T596-1996 " high-tension apparatus preventive trial rules ", stipulated the critical value of oil and paper water cut, as shown in table 1.
The critical value of table 1 water cut
The 5th, the reason of humidified insulation
Transformer insulated making moist mainly caused by following several factors:
(1) poor sealing.The transformer sealing poorly sealed meeting in position causes rainwater to invade transformer.If moisture leaks on coil along certain path, cause coil turn-to-turn short circuit, thus accidents caused.(2) hydrocooler leaks.Hydrocooler pipeline ftractures or snaps, and large quantity of moisture enters in transformer oil, causes coil burnout.(3) there is ponding the inside of inflow pipeline and earthen-ware pipe voltage equalizing ball inside, during installation, do not clean out, and moisture pours with oil with it device, causes insulation fault.(4) condensate water flows into.Moisture in transformer oil is evaporated in oil conservater, meets condensation knot.(5), there is gas side seepage in band oil transportation transformer in transportation, during installation, do not find, causes coil burnout after input.(6) hang cover inspection, device body exposure air makes moist, and oiling initial vacuum is processed not thorough, causes moisture to concentrate in insulation, causes insulation fault.
The 6th, the determination methods of humidified insulation
DL/T596-1996 " high-tension apparatus preventive trial rules " points out, judges the transformer insulated main test that relies on winding insulation resistance, dielectric loss and insulating oil etc. of making moist.When transformer station's depressor internal wetted, water content in oil and dampish impurity, easily form " foot bridge " and cause shelf depreciation and produce H2; The electrolytic action He Shui of moisture under electric field action and the chemical reaction of iron, also can produce a large amount of H2.The fault H2 accounting example in hydrogen hydrocarbon total amount of making moist in equipment is higher, so can judge humidified insulation fault by the hydrogen content detecting in transformer oil.
Transformer station's depressor Oil Dissolved Gases Concentration is basic identical with power transformer with the relation of corresponding fault, and when the effect due to impact load, in oil, the relative concentration of CO is higher, should arouse attention.
The gas composition that table 2 different faults type produces
In above analysis, can see: transformer oil is under hot and electric effect, decomposite hydrogen, carbon monoxide and multiple hydrocarbon gas, the composition of the type of device interior fault and the order of severity and these gas molecules and gas production rate close relation, utilize this to be related to the operation conditions of judgment device internal fault and surveillance equipment, become the indispensable means of oil-filled electric equipment safe operation, at home and abroad generally use, International Electrotechnical Commission has formulated special dissolved gas analysis guide rule IEC567 and IEC599, domestic GB17623 and the DL722 relevant criterion also formulated.Transformer core requires one point earth, only flows through the stray capacitance currents of each very little winding to iron core while normally moving in ground wire, as iron core has or multipoint earthing at 2, between earth point, forms closed-loop path, because interlinkage flux forms larger circulation.This electric current can cause local overheating, causes oil decomposition, burns out iron core etc., threatens transformer normally to move.Therefore, monitor that iron core grounding current prevents that its multipoint earthing from being very significant.As can be seen here, bushing shell for transformer insulated on-line monitoring, iron core grounding current monitoring and oil dissolved gas on-line monitoring technique are the effective means that realizes transformer station's electrical equipment.
As can be seen here, transformer is the equipment of important core, and its safe operation is most important, due to all many-sided reasons such as transformer station's depressor design, manufacture, quality of materials and operations, the pernicious fault of equipment happens occasionally, and has had a strong impact on the safe and stable operation of electrical network.
In electric system, for guaranteeing the safe operation of high-power transformer, for design feature and fault type and the importance of transformer, a lot of different on-line monitoring methods have been developed.In the at present domestic stage that has arrived comparative maturity on bushing shell for transformer insulated on-line monitoring, iron core grounding current monitoring and oil dissolved gas on-line monitoring technique, in power system transformer operation maintenance, obtained application comparatively widely.These technology and equipments, after completing the adaptability reform of electrified substation, can be used as the effective means of transformer station's depressor on-line monitoring.
At present, the independent monitoring of each characteristic quantity of transformer cannot judge running status and the fault signature of whole transformer comprehensively.
| The above transformer fault type of 220KV level |
| Oil is overheated |
| Oil and paper are overheated |
| Shelf depreciation in paper oil insulation |
| Spark discharge in oil |
| Electric arc in oil |
| Electric arc in oil and paper |
| Watered and wetting or bubble in oil |
Table 3
At present, HV Equipment On-Line Monitoring System comprises the plurality of devices such as Gas in Oil of Transformer on-line monitoring, transformer iron core grounding current on-line monitoring, capacitive apparatus on-line monitoring, voltage on-line monitoring, lightning arrester, isolating switch on-line monitoring, environmental monitoring, partial discharge monitoring.With regard to the above transformer of 220KV level, existing online technique monitoring has the multiple monitoring means such as gas in oil, iron core grounding current, capacitive sleeve pipe, system voltage transformer operating mode.Each monitoring means of transformer is independently installed, gather separately some status information of corresponding monitored equipment, and by such as the different communication protocol such as RS-485 by the data upload collecting to backstage, cannot accomplish running status and the fault of integrated system Platform Analysis and the above transformer of diagnosis 220KV level.
At present, the state parameter on-line monitorings such as transformer insulated have only been realized, but there is no unified transformer fault diagnosis unified platform, can be compared to patient and only know own Index for examination, cannot diagnose the state of an illness the same, only having transformer monitoring data and not diagnosing integral intelligent platform is to diagnose in time latency fault in transformer, the generation of great pernicious fault cannot be effectively prevented, safety, the reliability service of transformer station cannot be ensured.
Transformer is the equipment of important core in whole transformer station, and its safe operation is most important, and research and development Transformer's Condition Monitoring reference quantity intelligent integral diagnostic platform is imperative.
Under prior art condition, transformer monitoring is independently installed to multiple monitoring means, can make to occur in installation process the trouble that some are unnecessary, as expend a large amount of wire rods, device layout is unreasonable, and floor area is excessive etc.When subsequent expansion monitoring means, also need rewiring, cause quantities to strengthen, in monitoring means use procedure, cannot unify to analyze and management to monitoring means.On the other hand, infosystem isomerism also causes monitoring system based on privately owned communication protocols such as RS-485 can only realize station internal information sharing.This isomery shows as the following aspects:
Application heterogeneity: have tens application programs in operation, these application are usually the exploitations of a plurality of third party producer, and data standard is inconsistent;
Heterogeneous data: the data of enterprise are stored in each database and file with various incompatible forms;
Structural isomerism: company's various information system acquisition multiple architecture;
Platform isomery: the different hardware and the system software that are provided by a plurality of producers form computer system platform;
Network isomery: adopt multiple different communication network technology product to build different network transmission platforms;
When needing remote monitoring and management transformer, can only transmit data by other telecommunication protocol, cannot realize the data sharing between station and station, also cannot realize the access of the information comprehensive management platform of respectively standing.
All kinds of monitoring means of prior art condition transformer are independently installed, and gather separately some status information of corresponding monitored equipment, and all kinds of monitoring equipments establish one's own system, and product quality, technical merit are uneven.When running on same transformer station simultaneously, these systems must bring problems.Roughly have following some: repeated construction, waste money; Mutually by such as the different communication protocol such as RS-485 by the data upload collecting to backstage, be difficult to communication, be difficult to integrated; Day-to-day operation maintenance workload increases; Equipment is installed difficulty.Every cover system all has independently backstage diagnostic analysis software separately, and run unit is if by its data easy thing by no means of uniting.Said system also just rests on local and isolated state and fails really to form systematization and networking, cannot accomplish integrated system Platform Analysis and diagnose running status and the fault of the above transformer of 220KV level.More there is no 220 grades of above intelligent transformer diagnosis integral systems.
Summary of the invention
The present invention is intended to solve monitoring means and disperses to install the problems such as the optical fiber wire rod consumption causing is large, layout is unreasonable, native system comprises smart group cabinet and integral intelligent monitoring platform, by the on-line monitoring module integration around each transformer in smart group cabinet, relative position between each monitoring modular of reasonable development, make only need be connected with a small amount of wire rod between monitoring modular, communication transfer interface module and industrial computer the workload of minimizing project installation.By the integral intelligent monitoring platform on backstage, can reduce the interference of external complex electromagnetic environment simultaneously, improve the accuracy of Monitoring Data.As the unified background system of pith in the present invention, for operation, data structure and the analytical approach of traditional on-line monitoring system differentiation, invented one and deeply excavated data general character and analysis and diagnosis system.
The invention discloses the above transformer integral intelligent of a kind of 220KV level diagnostic system, it is characterized in that, comprise: a smart group cabinet, described smart group cabinet comprises an oil gas analysis module, an iron core grounding current monitoring modular, a capacitive casing monitoring module, a partial discharge monitoring module, a temperature monitoring module and a fan monitor module, the monitoring that transformer is relevant is provided and analyzes data; Integral intelligent diagnostic platform, comprises in a backstage, a distant place, a station end platform and a database, receive described smart group cabinet monitoring and and analyze data, and diagnose.
Reasonablely be, described smart group cabinet further comprises: some intelligent electronic device IED, correspondence is connected with described fan monitor module with described oil gas analysis module, described iron core grounding current monitoring modular, described capacitive casing monitoring module, described partial discharge monitoring module, described temperature monitoring module respectively, receives the monitoring of described module and analyzes data; One main IED, is connected with described some intelligent electronic device IED respectively, and is received the monitoring of each IED and analyzed data by bus to meet IEC61850 standard.
The method that the invention also discloses the above transformer integral intelligent of a kind of 220KV of employing level diagnostic system, comprises, step 1, with gas H
2, C
2h
2, whether ∑ C content and total hydrocarbon gas production rate exceed standard as the entry condition of diagnostic routine, if four conditions have one to exceed standard above and start diagnosis; Step 2, carries out just minute fault type, determines it is overheated or discharge fault on earth; Step 3, segments fault type judgement, determines it is the type of overheated or discharge fault on earth.
Reasonable, a described just minute fault type comprises: step 1, and extract the current measured data of described gas and carry out three ratio in judgement, three ratios return; Step 2, utilizes a neural network to judge, first data with existing is normalized, then carries out normalization data to proofread and correct, and then exports second layer output quantity, and proofreaies and correct; Step 3, the reasoning and judging of citing a precedent, chooses in existing described database and carries out reasoning with the immediate data of current data, the result of the reasoning that obtains citing a precedent; Step 4, comprehensive three kinds of methods and resultses judge be as the criterion to determine it is overheated or discharge fault on earth with two or more results.
Reasonable, described segmentation fault type judgement comprises: step 1, according to preliminary result, determine that overheating fault is that overheat of conducting circuit or magnetic conductive loop are overheated; The electric discharge that described discharge fault relates to solid insulation does not still relate to the electric discharge of estimating insulation, and secondary carries out three ratio in judgement to current raw data, obtains three ratio results; Step 2, secondary is normalized current raw data, and proofreaies and correct, and then exports second layer output quantity and proofreaies and correct, and obtains neural network result; Step 3, carries out the later reasoning and judging of citing a precedent of corrected parameter again, the result of the reasoning that obtains citing a precedent; Step 4, comprehensive three kinds of methods and resultses judge, with two or more results, are as the criterion, and determine it is the type of overheated or discharge fault on earth.
The present invention also solves the skimble-scamble problem of communication protocol of respectively standing simultaneously, by inner IEC61850 communication transfer interface module, the privately owned stipulations of original RS-485 are converted to the Standards Code that meets intelligent substation communication protocol, enable to realize the transformer equipment between each station of long-range unified monitoring management, advance intelligent substation transformation to build.
Transformer is the equipment of important core in whole transformer station, and its safe operation is most important, and the diagnosis of research and development Transformer's Condition Monitoring reference quantity intelligent integral is imperative, and important technology of the present invention solves:
A, each characteristic quantity monitoring integration of transformer;
B, all Transformer's Condition Monitoring amounts are unified in intelligent integral diagnostic platform and carry out diagnostic analysis;
C, adopt unified IEC61850 intelligence IED assembly to realize.
D, by station, hold platform and backstage, a distant place to carry out unified management to equipment immediate status and historical data base, information in the excavation mass data of system, and by system access intelligent grid integrated data platform from multiple support channels obtain reflection transformer state characteristic information, on this basis its running status is carried out to comprehensive diagnos, can reflect more in time, accurately, delicately the general level of the health of high-tension apparatus, thereby instruct the maintenance of transformer, to overcome the deficiency of classic method.
Intelligent transformer is the transformer that has added intelligent assembly, and intelligent assembly, by state aware and instruction executive component, is realized visual, the function integration of state, and the networking of control and robotization are supported for intelligent grid provides most basic function.
Accompanying drawing explanation
Below, with reference to accompanying drawing, for those skilled in the art, to the detailed description of the inventive method, above and other object of the present invention, feature and advantage will be apparent.
Fig. 1 is the structured flowchart that system of the present invention forms.
Embodiment
Refer to Fig. 1, be depicted as the composition frame chart of transformer integral intelligent diagnostic system of the present invention, by this block diagram, can recognize, transformer integral intelligent diagnostic system is applied in and exists different functional departments intelligent grid on-line monitoring and repair based on condition of component to be needed to the occasion of different rights, and this system is by adopting process layer---this hierarchy of wall---substation level---enterprises level, authority in can system is reasonably distributed, safeguards system safety, stable operation.
Particularly, transformer integral intelligent diagnostic system of the present invention relates to substation level and wall, part in wall is arranged in smart group cabinet 10, this smart group cabinet 10 comprises main IED101, and several intelligent electronic devices IED102-107 of the lower floor by IEC61850 transition of communications ... and the oil gas analysis module 111 of the lower floor communicating to connect respectively with each intelligent electronic device IED, iron core grounding current monitoring modular 112, capacitive casing monitoring module 113, partial discharge monitoring module 114, the data of temperature monitoring module 115 and fan monitor module 116 etc., backstage, a power transformation Ceng Nei distant place 201, the data of standing in end platform 202 and database 203.
The application scenario of native system also comprises enterprises level and process layer, intelligent grid integrated data platform 9 in enterprises level, and the data of transformer 8 are all delivered in transformer integral intelligent diagnostic platform 20 in process layer, thereby realized the above Transformer's Condition Monitoring intellectual monitoring of 220KV level integrated.
It should be noted that, due to the singularity of transformer device structure, in distributed on-line monitoring system, on-line monitoring cell sensor is dispersed and is arranged on everywhere, and each sensor need to be equipped with a whole set of corresponding protection facility simultaneously.And in the present invention; sensor is integrated in a smart group cabinet 10; can share each sensor protection implements common part on the one hand; greatly reduced on the other hand the quantity of transformer periphery on-Line Monitor Device; simplify installation, debugging and the maintenance work of on-line monitoring equipment, fully demonstrated intensive idea in management.
10 1, every each phase configuration smart group cabinet of main transformer, console mode outdoor installation, meets the IP55 degree of protection requirement of GB/T 4208 regulations; Smart group cabinet 10 is arranged on transformer side conventionally.In smart group cabinet 10, for different modules, adopt corresponding intelligent electronic device IED120-107, and the data that those IED are collected are sent to the monitoring platform 20 of rear end by main IED101, thus, each reference quantity monitoring modular unification of Transformer's Condition Monitoring is integrated into based on IEC61850 intelligence IED assembly integral intelligent group cabinet.
Oil gas analysis module 111 adopts gas chromatographic technique to detect.Measure composition and comprise H2, CO, CO2, CH4, C2H4, C2H6, C2H2, H2O.Minimum monitoring periods should be not more than 2 hours, and monitoring periods is adjustable.Should be able to carry out fault diagnosis according to gas composition and content, ratio and rate of growth etc., within every 24 hours, to main IED, report and submit message.Adopt power down non-volatile memory technology at least to store 1 year above Monitoring Data, if desired, can via main IED, call Historical Monitoring data by station level networking.In oil, the sensing range of gas and precision are as follows.
| Sequence number | Gas | Minimum detectable concentration | Sensing range | Accuracy of detection |
| 1 | H2 | 1ppm | 1-5000ppm | ± 10% or 2ppm get large person |
| 2 | CO | 1ppm | 1-5000ppm | ±10％ |
| 3 | CH4 | 0.5ppm | 0.5-4000ppm | ± 10% or 2ppm get large person |
| 4 | C2H6 | 0.5ppm | 0.5-3000ppm | ± 10% or 2ppm get large person |
| 5 | C2H4 | 0.5ppm | 0.5-4000ppm | ± 10% or 2ppm get large person |
| 6 | C2H2 | 0.1ppm | 0.1-2000ppm | ± 10% or 1ppm get large person |
| 7 | Total hydrocarbon | 0.2ppm | 0.2-8000ppm | ± 10% or 2ppm get large person |
| 8 | Micro-water | 1ppm | 1-100ppm | ± 10% or 2ppm get large person |
Table 4
Iron core grounding current monitoring modular 112 adopts the electric current on circle punching CT monitoring iron core grounding lines, and I is measured and should be not more than 1mA, and maximum detection amount should be not less than 5A.Minimum monitoring periods should be not more than 1min, regularly to main IED101, reports and submits measurement result, and the cycle is adjustable.Sensing range and the precision of iron core and folder are as follows:
Table 5
In capacitive casing monitoring module 113, the major insulation of capacitive battery current transformer, coupling condenser, CVT, these capacitor type high-tension apparatuses of condenser-type terminal can be regarded as and consists of several capacitor's seriess.The voltage-to-ground of a high-pressure conductor is by these series capacitor shareds.For example, a high-voltage capacitance fuse for certain model 220kV capacitive battery current transformer (CT), has 6 " main screens ", (by aluminium foil or conductive paper, being made), the directly grounded one deck of outermost is called " end shield ", between every two " main screens " coiling the kraft capacitor paper of multilayer.During installation, under vacuum state, whole capacitor core is dipped in insulating oil, forms paper oil insulation, " end shield " guides to high voltage porcelain bushing external ground through a small casing.Like this phase voltage of 127kV by high-pressure conductor the capacitor shared to 6 series connection of end shield.Condenser-type terminal has similar structure with CT, and its " end shield " also drawn ground connection.The high-voltage capacitance inside of coupling condenser and CVT consists of a plurality of capacitances in series, and their head end connects high pressure, the direct ground connection of tail end or through communication carrier machine ground connection.
The major insulation of capacitance type equipment is born a sub-high pressure, to there is leakage current Ix to flow through, insulation dielectric can produce electricity and lead loss and polarization loss under alternating electric field, and they produce dielectric loss jointly, so just contain real component and idle component in leakage current.Major insulation can be equivalent to the parallel model of electric capacity and resistance.
tanδ＝Ic/Ir＝tan[90°－(ΦIx-ΦUx)] (2-1)
C＝Ix/ωU (2-2)
Dielectric dissipation factor tan δ is for finding that insulation integrity defect is very sensitive, if capacitance type equipment makes moist in operational process, deteriorated or certain layer capacitance occurs puncture, the main capacitance amount of equipment will change, so the electric capacity of monitoring capacitance type equipment, equally also can find insulation defect very effectively.
The resistive component of leakage current is very little, so the numerical value of dielectric dissipation factor is also very little.Generally, tan δ < 1.0% of 110kV and above capacitance type equipment, deals with improperly during measurement and will cause larger error, and Measurement accuracy dielectric loss difficulty is very large.
Partial discharge monitoring module 114 adopts internally-arranged type UHF-antenna receiving type monitoring technology scheme or ultrasonic technology scheme, the local discharge signal that 114 pairs of each sensors of monitoring modular are put in office is sampled, each sampling length is 50 power frequency periods, the shortest monitoring periods is not more than 1 hour, and monitoring periods is adjustable.Office puts 114 pairs of local discharge characteristic information of monitoring modular and analyzes, and comprises: electric discharge amplitude, discharge phase, unit interval discharge time.Possesses certain Fault Pattern Recognition function.Normal condition, reported an assessment result every 6 hours to main IED; Abnormal signal detected, active upload report, Real-Time Monitoring.Office puts and in monitoring modular 114, can preserve 1 year above characteristic information and the real time data of 24 hours, adopts power down non-volatile memory technology.When receiving request, can to the server of main IED101 or backstage monitoring integration platform 20, send by station level networking characteristic information and the real time data of storage.
The workflow of introducing native system below in conjunction with backstage monitoring integration platform 20.
Diagnosis basic procedure comprises:
1. diagnosis starts
With gas H
2, C
2h
2, whether ∑ C content and total hydrocarbon gas production rate exceed standard as the entry condition of diagnostic routine, if four conditions have one to exceed standard above and start diagnosis.
2. just divide fault type
A, extraction gas H
2, C
2h
2, CH
4, C
2h
6carry out three ratio in judgement with the current measured data of ∑ C, three ratios return to 1---overheating fault, and 2---discharge fault;
B, utilize existing neural network to judge, first data with existing is normalized, then carries out normalization data to proofread and correct, then export second layer output quantity, and proofread and correct.Obtain neural network result 1---overheating fault, 2---discharge fault;
C, the reasoning and judging of citing a precedent, choose in data with existing storehouse and carry out reasoning with the immediate data of current data through mathematical computations, result 1---the overheating fault of the reasoning that obtains citing a precedent, and 2---discharge fault;
D, comprehensive three kinds of methods and resultses judge be as the criterion to determine it is overheated or discharge fault on earth with two or more results.
3. segment fault type
A, according to preliminary result, determine that overheating fault is that overheat of conducting circuit or magnetic conductive loop are overheated; The electric discharge that discharge fault relates to solid insulation does not still relate to the electric discharge of estimating insulation.Secondary carries out three ratio in judgement to current raw data, and (the comparison Xiang Hechu office of judgement is also different, and according to being just divided into electric discharge or overheated three-ratio method different, obtain three ratio result 1---overheat of conducting circuits down together), 2---magnetic conductive loop is overheated or 1, and---relating to the electric discharge of solid insulation, 2---do not relate to the electric discharge of solid insulation;
B, secondary are normalized (normalized weights and first that divide and different) to current raw data, and proofread and correct, and then export second layer output quantity and proofread and correct.---magnetic conductive loop is overheated or 1, and---relating to the electric discharge of solid insulation, 2---do not relate to the electric discharge of solid insulation to obtain neural network result 1---overheat of conducting circuit, 2;
C, again carry out the later reasoning and judging of citing a precedent of corrected parameter, result 1---the overheat of conducting circuit of the reasoning that obtains citing a precedent, 2---magnetic conductive loop overheated or 1---relating to the electric discharge of solid insulation, 2---, does not relate to the electric discharge of solid insulation;
D, comprehensive three kinds of methods and resultses judge, with two or more results, are as the criterion, and determine it is the type of overheated or discharge fault on earth.
Transformer synthesis diagnostic method based on rough set
A lot of characteristic informations of oil-filled transformer often can reflect from different aspect the situation of transformer operation, the expression-form of every kind of characteristic information is different, and faults all has some limitations, the feature that just must extract multiple monitoring method is carried out overall treatment and Cooperative Analysis.In addition, some tests are difficult to carry out at any time (such as winding deformation, office, putting the power failure pilot projects such as monitoring), cause again the incomplete or monitoring information disappearance of failure message.We did deep research by expert system, fuzzy mathematics, neural network etc. to above problem in the past, but diagnostic result is still unsatisfactory sometimes.This project is incorporated into rough set in transformer fault diagnosis, segments diagnosis using rough set method to be combined the signs such as electrical test, tour, annex on the reasoning two-stage diagnostic result basis of citing a precedent based on artificial neural network again.
Fault diagnosis based on rough set
1) conditional attribute set and decision attribute set determines
According to the ultimate principle of rough set and fault diagnosis, first take failure symptom as conditional attribute, fault be decision attribute, the Power Transformer Faults data of collecting are carried out to statistical study, and with reference to more successful failure modes collection in experience before, obtain conditional attribute set and decision attribute set as shown in table 6 and table 7.
The set of table 6 conditional attribute
Table 7 decision kind set
2) formation of decision table
Some fault cases in research process, have successively been collected, begin to take shape thus corresponding relation, also by following three kinds of methods, make up the few shortcoming of fault case: first, by gathering information, obtain forefathers with some more ripe faults that obtain after the researchs such as other intelligent diagnosing methods and the corresponding relation between failure symptom, by selected fault and failure symptom, it is arranged; The second, by obtaining some simple corresponding relations about the principle of fault and failure symptom arranges in technical information; The 3rd, to the formed preliminary corresponding relation of above-mentioned two kinds of methods, after the suggestion in conjunction with experience personnel, then it is perfect to modify.Obtain thus the fundamental relation of transformer fault and failure symptom.
3) rule set forms and application
By above-mentioned definition, write the storing process of decimation rule.Formed after rule set, can carry out fault diagnosis by applying rules set pair follow-up transformer, its process is as follows:
1. first the information of follow-up transformer is processed, in system, by two kinds of methods, determined follow-up property value: on the one hand by the processing to online data and mini-test data, by what surpass early warning value, being 1, is 0 normally; Mode confirmed test item attribute by page man-machine interaction is 0 or 1 on the other hand, and on system runnable interface, 1 meaning is for making hook, and the fault that is about to occur is selected.
2. in yojan, concentrate conform to the follow-up conditional attribute numbering of yojan of search, as what do not conform to completely, just find out several (getting more than 3) the most close with it.
3. according to the yojan numbering search obtaining, obtain corresponding yojan decision table, the follow-up data that obtain are mated with yojan decision table, with the rule set that obtains conforming to most.
4. find after the rule set conforming to, can in rule set, find the rule identical with conditional attribute value, as there is no the identical the most close rule of just choosing, thereby obtain diagnosis.
The present invention is integrated around the monitoring modular integrated intelligent of the above transformer of same 220KV level, under Platform of hardware based on unified, realized Transformer's Condition Monitoring, the layered distribution type integrated system adopting has overcome the above-mentioned defect of autonomous system in the past, the hardware platform based on unified, unified communication protocol, unified backstage analyzing and diagnosing software systems: the running status and the fault that really realize integrated system Platform Analysis and the above transformer of diagnosis 220KV level; Real realization can reduce the impact of external electromagnetic interference on Monitoring Data; The real quantities that has also reduced installation when saving optical fiber wire rod that realizes; Smart group cabinet adopts real realization of the structure of drawer type to insert the i.e. effect of use; Really realize the authority reasonable distribution of the different functional departments of intelligent grid to detection system; Really realize Transformer's Condition Monitoring intelligent integral; Really realize intelligent transformer diagnosis and analyze integrated; The uniform data modeling of employing standard, according to the storage of master pattern, has truly realized the shared resources of status information of equipment by the data that gather; Standard interface is externally provided, makes application newly developed can get easily the data message of comprehensive platform, be conducive to better excavate integrated data platform information value; Platform provides abundant information to represent means, can make user find more easily the information that oneself is concerned about, better supports level of decision-making; Platform has reliable and stable operating mechanism, and simultaneously platform can be processed mass data, be suitable as very much transformer state information storage, serve and represent center.
Before the description to preferred embodiment is provided so that any technician in this area can use or utilize the present invention.Various modifications to these embodiment are evident for personnel skilled in the art, and total application of principle described here can not used to creativeness to other embodiment.Thereby the present invention is the embodiment shown in being not limited to here, and should be according to meeting the principle that disclosed and the wide region of new feature here.
Claims (5)
1. the above transformer integral intelligent of a 220KV level diagnostic system, is characterized in that, comprising:
One smart group cabinet, described smart group cabinet comprises an oil gas analysis module, an iron core grounding current monitoring modular, a capacitive casing monitoring module, a partial discharge monitoring module, a temperature monitoring module and a fan monitor module, the monitoring that transformer is relevant is provided and analyzes data;
Integral intelligent diagnostic platform, comprises in a backstage, a distant place, a station end platform and a database, receive described smart group cabinet monitoring and and analyze data, and diagnose.
2. the above transformer integral intelligent of 220KV level according to claim 1 diagnostic system, is characterized in that, described smart group cabinet further comprises:
Some intelligent electronic device IED, correspondence is connected with described fan monitor module with described oil gas analysis module, described iron core grounding current monitoring modular, described capacitive casing monitoring module, described partial discharge monitoring module, described temperature monitoring module respectively, receives the monitoring of described module and analyzes data;
One main IED, is connected with described some intelligent electronic device IED respectively, and is received the monitoring of each IED and analyzed data by bus to meet IEC61850 standard.
3. adopt a method for the above transformer integral intelligent of 220KV level claimed in claim 1 diagnostic system, it is characterized in that,
Step 1, with gas H
2, C
2h
2, whether ∑ C content and total hydrocarbon gas production rate exceed standard as the entry condition of diagnostic routine, if four conditions have one to exceed standard above and start diagnosis;
Step 2, carries out just minute fault type, determines it is overheated or discharge fault on earth;
Step 3, segments fault type judgement, determines it is the type of overheated or discharge fault on earth.
4. the method for the described above transformer integral intelligent of 220KV level diagnostic system according to claim 3, is characterized in that,
A described just minute fault type comprises:
Step 1, extracts the current measured data of described gas and carries out three ratio in judgement, and three ratios return;
Step 2, utilizes a neural network to judge, first data with existing is normalized, then carries out normalization data to proofread and correct, and then exports second layer output quantity, and proofreaies and correct;
Step 3, the reasoning and judging of citing a precedent, chooses in existing described database and carries out reasoning with the immediate data of current data, the result of the reasoning that obtains citing a precedent;
Step 4, comprehensive three kinds of methods and resultses judge be as the criterion to determine it is overheated or discharge fault on earth with two or more results.
5. according to the method for the described above transformer integral intelligent of the 220KV level diagnostic system described in claim 3 or 4, it is characterized in that,
Described segmentation fault type judgement comprises:
Step 1, determines that according to preliminary result overheating fault is that overheat of conducting circuit or magnetic conductive loop are overheated; The electric discharge that described discharge fault relates to solid insulation does not still relate to the electric discharge of estimating insulation, and secondary carries out three ratio in judgement to current raw data, obtains three ratio results;
Step 2, secondary is normalized current raw data, and proofreaies and correct, and then exports second layer output quantity and proofreaies and correct, and obtains neural network result;
Step 3, carries out the later reasoning and judging of citing a precedent of corrected parameter again, the result of the reasoning that obtains citing a precedent;
Step 4, comprehensive three kinds of methods and resultses judge, with two or more results, are as the criterion, and determine it is the type of overheated or discharge fault on earth.
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