CN1811474A - Transformer dynamic stability state parameter tester and diagnostic software - Google Patents

Abstract

The present invention relates to a transformer dynamic stability condition parameter testing apparatus and its diagnosis software. Said product is composed of testing apparatus and diagnosis software, and said invention is characterized by that it adopts a low-voltage reactance method to diagnose the winding deformation of power transformer and changed condition of iron-core looseness in the place so as to create a set of complete high-effective detection and diagnosis method, its detection accuracy is high, can be up to 0.2 grade.

Description

Moving steady state parameters tester of transformer and diagnostic software

1 technical field

This project belongs to electric power information and robotization, digitizing state-detection instrument and the status of electric power maintenance software in light mechanical and electrical integration field.

Appraisal of scientific and technological achievements by Gansu Province science and technology bureau tissue in 2003.

Won the technological innovation fund project verification certificate of the Ministry of Science and Technology, Ministry of Finance's approval in 2003.

State Grid Corporation of China is organizing drafting of low-voltage short circuit impedance method standard, and detection that this project works out and diagnostic method will be put into industry standard.

This project is made up of detecting instrument and diagnostic software two parts.Detecting instrument is born the basic test of transformer, is used for accurately measuring the moving steady state (SS) parameters of transformer.Diagnostic software is for detected various parameters, initial conditions and running environment with reference to transformer, according to relevant criterion,, carry out analysis-by-synthesis in conjunction with expertise, automatic diagnosis goes out power transformer bear short-circuit current rush after, moving steady state (SS) has or not deterioration (winding deformation, displacement and iron core looseness) trend and degradation, and assesses the transformer operational reliability according to this, and then make a decision transformer and whether need the core body maintenance or upgrade, guarantee safe operation of power system.

The major technique content of this project, characteristics are as follows:

1.1 low-voltage method: directly use on-the-spot civil power (220V) or lower voltage as experiment power supply, the testing and diagnosing power transformer moves steady state (SS) (winding deformation, iron core displacement) degree.

1.2 the accuracy of measurement data and reproducibility reach that GB requires ± and 0.2 grade.

1.3 surveying instrument main performance index

Voltage (real effective): 0.2 grade of electric current (real effective): 0.2 grade of frequency: 0.1 grade of impedance voltage: 0.2 grade of short-circuit impedance: 0.2 grade of short-circuit reactance: 0.2 grade of leakage inductance: 0.2 grade

Loss: COS Φ 〉=0.5 o'clock, 0.2 grade

0.5＞COS Φ 〉=0.1 o'clock, 0.5 grade

0.1＞COS Φ 〉=0.02 o'clock, 1.0 grades

1.4 diagnostic software has automatic diagnostic function

Succeeding in developing of this project do not have instrumentation to use the test problem that the low-voltage impedance method detects the moving steady state parameters of transformer at the scene with solving for many years, makes power transformer detect diagnostic techniques simultaneously and realizes that robotization with intelligent, fills the domestic gaps.

This project is applied at home, now uses (annex: user list) createed considerable economic and social benefit at more than 50 power supply department of more than 20 provinces and cities and transformer manufacturing plant.

2 background technologies

Electrical network is one of economic lifeline of country, the most valuable most important equipment is large-scale power transformer in the electrical network, guarantee that the power transformer safe operation is the most important thing of power equipment management work, cause economic loss in order to reduce the short-circuit of power transformer fault, avoid the great power outage of power supply grid, State Power Corporation repeatedly holds " whole nation prevention transformer short-circuit damage accident special topic work meeting ", hereinafter require each transformer manufacturing plant and applying unit to actively develop the repair based on condition of component work of transformer, explicitly call for 110kV and above electric pressure transformer are done the short-circuit impedance detection, trying one's best drops to bottom line with transformer damage accident rate.

Before this product development, the domestic and international market does not still have the special inspecting equipment that detects the moving steady state parameters (containing short-circuit impedance, short-circuit reactance, leakage inductance) of transformer.And traditional detection method is loaded down with trivial details, measuring error is big, precision is low, the reproducibility difference does not reach shortcomings such as 0.2% GB requirement.Market in urgent need to develop a cover according to have advanced technology, automaticity height, measuring accuracy height, function complete, use moving steady state detection detector of light transformer and diagnostic software.Calendar year 2001 Gansu Province science and technology bureau approval project verification.

This product is in R﹠D process, State Power Corporation, national DianKeYuan, Gansu Power Company, Gansu Province science and technology bureau have been obtained, leaders of unit such as Tianshui Office of Science and Technology and expert's support energetically, succeeded in developing in 2003, in June, 2003 is by being organized appraisal of scientific and technological achievements (assay certificate number: No. the 116th, sweet section mirror word [2003]) by Gansu Province science and technology bureau.Won the Ministry of Science and Technology, Ministry of Finance's technological innovation fund (No. [2003] 375, meter word are sent out by state section) in 2003." 2004 annual state key new product plannings (No. [2004] 140, meter word are sent out by state section) have been applied for listing in.

Succeeding in developing of this product, filled up domestic blank, having solved does not have instrumentation to use the problem that the low-voltage reactance method detects the moving steady state parameters of transformer at the scene for many years, for prevention transformer short-circuit damage accident provides reliably, analyzing and diagnosing foundation accurately, reach reduction transformer major accident rate, reduce the bad social influence and the economic loss that cause because of electric power accident, thereby guarantee the power equipment safety operation.

3 summary of the invention

3.1 the electronic measurement technique and the micro computer digital processing technology of abundant uses advanced, realization accurate detection and data are handled automatically, and testing result accuracy and reproducibility reach GB fully and require ± 0.2%.Overcome the technical barrier that the traditional measurement instrument can't be up to standard.

3.2 realize that application low-voltage method accurately detects the technical merit of diagnosing transformer to move steady state parameters at the scene and belongs to advanced international level.

3.3 create advanced, complete a, reliable detection of cover and a diagnostic method, diagnose deformation of transformer winding and iron core displacement that an effective means of testing is provided for detecting, filled up domestic blank.

3.4 integrated computer hardware and software technology, the utilization single chip control module, exploitation higher synthesis diagnostic software, realize power transformer digitizing state-detection and intelligent diagnosis, this technology is penetration and promotion at home, to effectively promote the development of China's status of electric power maintenance, promote detection, fault diagnosis and the maintenance level of China's power high voltage equipment.

3.5 this product design is designed to portable construction, supporting have a diagnostic software, is used for the on-the-spot diagnosis that detects.

4 description of drawings

Figure below further specifies this project in conjunction with the accompanying drawings and embodiments

Fig. 1 is the circuit theory diagrams of this project

Fig. 2 is the diagnostic software main program flow chart of this project

The higher synthesis of this project of Fig. 3 is diagnosed soft program flow diagram

Three Single Phase Transformer Set wiring diagrams of this project of Fig. 4

Three Single Phase Transformer Set bands of this project of Fig. 5 mutual inductor wiring diagram

The pressurized winding of the detection of this project of Fig. 6 is the winding parameter of the three-phase transformer of Y0 wiring, three-phase and four-line method wiring diagram;

The pressurized winding of the detection of this project of Fig. 7 is the winding parameter of the three-phase transformer of Y0 wiring, three-phase and four-line method belt current mutual inductor wiring diagram;

The pressurized winding of the detection of this project of Fig. 8 is that the winding of the three-phase transformer of Y0 wiring divides phase parameter.Single phase poaer supply method (this figure is only corresponding to surveying B phase winding parameter) wiring diagram;

The pressurized winding of the detection of this project of Fig. 9 is that the winding of the three-phase transformer of Y0 wiring divides phase parameter.The single phase poaer supply method of belt current mutual inductor (this figure is only corresponding to surveying B phase winding parameter) wiring diagram;

Figure 10 is that the pressurized winding of the detection of this project is the winding parameter of the three-phase transformer of Y (or Δ) wiring.Phase three-wire three method wiring diagram;

Figure 11 is that the pressurized winding of the detection of this project is that the winding of the three-phase transformer of Y wiring divides phase parameter.Single phase poaer supply method (this figure is only corresponding to the complex parameter of surveying BC two phase windings) wiring diagram;

Figure 12 is this project panel front elevation.

4.1 general introduction

The transformer that moves in the electrical network often is subjected to the short-circuit impact under the various service conditions. At present, some is domestic large-scale Transformer does not also reach the requirement that adapts to the grid short circuit accident fully, so, during the transformer fault that caused by short-circuit impact Generation is arranged.

Be prevention transformer short-circuit damage accident, [2000] No. 589 files that State Power Corporation issues " prevent electrical production 25 important requirements of major accident " 15.2.5 bar regulation in (hereinafter to be referred as " 25 counter arranging "): " right 110KV and above transformer should be done the test of low-voltage short-circuit impedance before dispatching from the factory and going into operation ... to stay original note Record ". Article 15.6, stipulate again: " ... transformer should be made the low-voltage short-circuit impedance and survey after suffering the near region sudden short circuit Examination ..., and with original record relatively, judge that transformer does not have fault after, can put into operation. " GB GB1094.5? 985 " electricity The power transformer " in, not only stipulated the short-circuit test method, but also stipulated that transformer stands declaring of short-circuit current rush According to, whether the variation of the transformer of regulation circular shape concentric formula winding reactance value before and after short-circuit current rush is declared greater than 2% conduct The foundation that whether requires to carry out strip inspection of disconnected transformer. Is International Electrotechnical Commission in new standard IEC 60076?: 2000 In to using reactance method to judge that Transformer Winding displacement, distortion made recommendation and standard. This shows, use the low-voltage short circuit Reactance method judges that it is in Operation of Electric Systems with in safeguarding for a long time that transformer is subjected to whether to break down after the short-circuit current rush Approved, and listed in the reliable method of relevant regulation by electric administrative department at different levels.

4.2 low-voltage short-circuit reactance method principle

Transformer Short Circuit Impedance is the equiva lent impedance of transformer inside when load impedance is zero. The reactive component of short-circuit impedance,

Generally can think it namely is the leakage reactance of Transformer Winding. The leakage reactance of winding comprises horizontal leakage reactance and vertical leakage reactance Two parts, but no matter be horizontal leakage reactance or vertical leakage reactance, its reactance value all are that the physical dimension by winding is determined .

For a transformer, when winding deformation, when physical dimension changes, its short-circuit reactance value also changes.If operating transformer is subjected to the impact of short-circuit current, in order to check whether its winding is out of shape, short-circuit reactance value in the time of dispatched from the factory by short-circuit reactance value behind the short-circuit impact and transformer compares, and judges according to its intensity of variation whether transformer winding, distortion unshakable in one's determination, displacement and fault degree thereof take place.Because the short-circuit impedance value is similar to the short-circuit reactance value, also available short circuit impedance method is judged.

4.3 transformer moves steady state parameters tester basic functional principle (Fig. 1)

After tested voltage U and electric current I parameter are isolated through sensor (voltage, current transformer), be input to back level metering circuit (voltage, electric current and performance number test), 9 road signals of metering circuit output are input to the data sampling holding circuit simultaneously, the Single-chip Controlling holding circuit locks 9 road signals simultaneously, reading of data, carry out computing, demonstration, printout, and data transmission is carried out diagnostic process to PC by the RS232 interface.The each several part circuit function is as follows:

Voltage input circuit and electric current input circuit have adopted high precision zero magnetic flux mutual inductor, and its advantage is that precision height, good linearity, volume are little, the voltage measurement scope reaches 30～500V, and current measuring range has reached 0.03～60A.The true root-mean-square valve metering circuit of voltage and current can take place accurately to measure under the serious distortion situation at waveform, can guarantee the high-acruracy survey of voltage, current reference amount.0.02 grade of low-power meter (import instrument) measuring principle has been used for reference in the design of low power factor power-measuring circuit, and the accuracy of its measured value and stability belong to leading domestic level.The data sampling holding circuit can make voltage, electric current, power signal gather simultaneously and preserve, and can improve the discreteness of measurement data greatly.The digital circuit test that combines with mimic channel has improved measuring accuracy, reaches intelligent test.

5 traditional measurement method technological deficiencies are analyzed:

Traditional method detects Transformer Winding and has or not when being out of shape, and need use many instrument combines at the scene.Even adopt the low-voltage method still to need more than ten instrument such as voltage table, reometer, frequency meter, low power-factor wattmeter, pressure regulator and equipment are combined into a test macro.Shortcoming is:

5.1 field wiring is cumbersome, workload is big;

5.2 detect high voltage, the actual power factor value very low (cos φ 〉=0.02) when the high-power transformer winding moves steady state parameters, the domestic production low power-factor wattmeter can only be accomplished cos φ 〉=0.1 at present, existing instrument is difficult to competent this test;

5.3 the on-the-spot interference of electromagnetic field that exists causes the Ferraris instrument measuring error big;

5.4 the serious distortion of current waveform during test, the change of adding network load causes the variation of the voltage of experiment power supply, and also change in ± 1% scope of supply frequency makes that the reading of instrument is inaccurate;

5.5 require when measuring to convert again, be difficult to accomplish by accomplishing that manually moment accurately reads ten platform instrumented datas simultaneously;

5.6 more difficult accomplish be the dispersiveness that requirement repeats repeatedly measurement data reach ± 0.2%;

Above-mentioned factor is to cause the accuracy of final testing result and reproducibility not to reach the main cause of GB regulation ± 0.2% technical requirement, and this is the deficiency of traditional measurement instrument, is the main difficult technical that this project will solve.

6 projects have solved several critical technical barriers in development process:

6.1 because this project is to be applied to on-the-spot the detection, how the very strong electromagnetic interference (EMI) of on-the-spot existence guarantees the accuracy of measurement data and the technical barrier that reliability is this project;

6.2 because this project demand is tested under low-voltage, and magnitude of voltage is low can also to guarantee the accuracy of measurement data to how many volts, and not having ripe experience in the past can be for reference, and the suggestion of brainstrust is also inconsistent, this is again an individual technical barrier again;

6.3 will analyze detected data, relatively, judge, need a cover theoretical foundation and do the basis, there is the strict detection method of a cover to guarantee that these all need us to go research, exploitation, summing up experience, makes complete detection and the diagnostic method of a cover.

For overcoming the deficiency of traditional measurement instrument, this project is developed the electronic measurement technique and the micro computer digital processing technology of application of advanced in design, at the above-mentioned various unfavorable factors that the scene exists, after the process serious analysis, understand fully reason, make corresponding solution.Adopt integrated design, be suitable for on-the-spot test, wiring is simple, easy to operate, increases work efficiency; When adopting high precision, power-measuring circuit cuts apart multiplication, voltage, current measurement circuit adopt true rms measurement, study for a second time courses one has flunked correction with software simultaneously, measurement accuracy has been reached require index ± 0.2% in the GB, the test specification of power factor has reached cos Φ 〉=0.02; The structure division of surveying instrument adopts bilayer screen worn-out, and metering circuit partly adopts the worn-out screen of hardware screen to shield worn-out the combination with software, has improved anti-interference greatly; Measurement data be by system controlled by computer with three magnitudes of voltage, three current values, three performance numbers lock simultaneously, reading, carry out data processing again, make the reproducibility of measurement data reach GB fully and require 0.2 grade of index.Pass through test of many times again, improve repeatedly, finally solved these critical technical matterss.

The design proposal of 7 diagnostic softwares (Fig. 2)

The design proposal of diagnostic software is divided into elementary diagnosis and high level diagnostics, the fundamental purpose of elementary diagnosis is the moving steady state (SS) correlation parameter of transformer that detecting instrument can be measured, pass through software initial analysis, comparison, calculate error amount, compare with the relevant criterion value again, diagnose out the PRELIMINARY RESULTS value; The fundamental purpose of high level diagnostics is on the tentative diagnosis basis, diagnosis experience in conjunction with expert's proposition, sum up the diagnosis experience of actual measurement example, behind the analysis-by-synthesis various factors, the moving steady state (SS) of definite diagnosis transformer has or not deterioration and degradation, and assessment transformer operational reliability, feasible maintenance suggestion is proposed.

7.1 elementary diagnostic software design proposal:

7.1.1 can set up the moving steady state parameters database of every tested transformer;

7.1.2 can tentatively judge winding deformation and degree of displacement unshakable in one's determination;

7.1.3 have the examining report of printing function;

7.1.4 have query function;

7.1.5 it is compatible: as to run on Windows98 operating system;

Has remote communicating function.

7.2 the design proposal of high level diagnostics software:

7.2.1 it is compatible: as to run on Windows98/Windows Me/Windows2000 operating system;

7.2.2 set up databases such as transformer primary data, test data, running environment data, incident data, auxiliary data, normal data comprehensively;

7.2.3 perfect Various types of data storage, calculating, comparison, analysis, query function;

7.2.4 Xian Jin expert intelligence diagnostic function comparatively, comprehensive diagnos goes out deformation of transformer winding, iron core degree of displacement;

7.2.5 transformer fault warning function;

7.2.6 telecommunication, resource sharing function.

7.3 the design of elementary diagnostic software:

7.3.1 the detection of winding parameter and diagnosis

7.3.2 trichotomy: the mean value of the three-phase impedance voltage value of detection Transformer Winding and the short-circuit impedance value of phase-splitting.Impedance voltage value (rated condition) compares when dispatching from the factory with transformer, the three-phase shortcircuit impedance mutually than;

7.3.3 single plane method: detect impedance voltage, short-circuit reactance, the leakage inductance value of each phase winding of transformer respectively, three single-phase data are contrasted mutually, compare with original value.

7.3.4 the diagnosis main method of winding parameter is exactly: vertical ratio and horizontal than (data of being indulged ratio and horizontal ratio should be same transformer, same to same parameter winding, on same tap gear); Vertical ratio: this measured data of same parameter and raw data with last time measured data compare.To judge that not only whether its relative variation has surpassed regulation, also should analyze the trend of its variation.First after the test, vertical than the time, U _kWith relatively should being absolutely necessary of name plate rating; Horizontal ratio: same parameter compares mutually between same (group) transformer three-phase; The result of vertical ratio and horizontal ratio tackles according to analysis, comprehensive diagnos, and than being benchmark, horizontal ratio is for assisting with vertical.

For realizing above-mentioned diagnostic function, must set up the source data bases that comprises the delivery test value.

7.3.5 criterion (demand value): bear the scope of short-circuit current rush test reactance value permission afterwards variation at IEC IEC60076 for transformer?: 2000 with China GB GB1094.5 (declaration original text) in all have clear and definite and consistent regulation.The all existing both at home and abroad suitable experience of the moving steady state (SS) of field measurement winding four parameter diagnosis Transformer Winding.Before moving steady state detection is diagnosed guiding rules appearance to transformer in service, relevant regulations and the relevant introduction that is seen in various documents according to GB, in conjunction with the practice results following informative criterion is proposed, help on-the-spot detection and diagnosis, be of value to further simultaneously and accumulate experience.Followingly carry the power transformer that criterion is only applicable to capacity 2500kVA above (being indication II in the GB 1094.5, III class).2500kVA and following substation transformer can be with reference to tentative.The transformer of other kind as: rectifier transformer, furnace transformer, impedance voltage less than 3% transformer ... determine separately Deng the reply concrete condition.

Vertical ratio: as long as one group of data is arranged, should draw attention to,, should not continue operation as long as suggestion takes technical measures to have one group greater than 5% o'clock greater than 2% o'clock.

Horizontal ratio: as long as one group of data is arranged greater than 2% o'clock, should draw attention to, suggestion takes technical measures greater than 5% o'clock, should not continue operation.

7.4 the detection of iron core parameter and diagnosis

7.4.1 detect

Single plane method: detect the low no-load current I that decides transformer core under the voltage (231V) _ODWith open circuit loss P _OD, unloaded equivalent impedance Z _OD

The diagnosis of iron core parameter: the fundamental purpose of this detection is to diagnose transformer core that the moving deteriorations of stablizing such as non-loosening, displacement, (short circuit between possible secondary multipoint earthing unshakable in one's determination, sheet) are arranged.

Test no-load current and open circuit loss can diagnose out the depressor winding to have or not circle interlayer fault.But in a single day the circle layer short circuit takes place, the differential and heavily instantaneous tripping operation of protection meeting of power transformer, main transformer is out of service.Then this detection is actually in the character of determining fault.

7.4.2 diagnosis

Vertical ratio, its intension is vertical than similar with the moving steady state (SS) diagnosis of method and winding.But name plate rating is unavailable.

Horizontal ratio, three mutually than.Be actually by the measured data of traditional wired method (on this instrument service manual standard being arranged) mutually than, for easy.

Order: $K_1=\frac{2|\mathrm{Pab}-\mathrm{Pbc}|}{\mathrm{Pab}+\mathrm{Pbc}};$ $K_2=\frac{\mathrm{Pca}}{\mathrm{Pab}};$ $K_3=\frac{\mathrm{Pca}}{\mathrm{Pbc}}.$

7.5 the design of high level diagnostics software (Fig. 3)

High level diagnostics software will be promoted on elementary diagnostic software function basis comprehensively, the experience that embodies a concentrated reflection of out the transformer manufacturing and use the art brainstrust to accumulate for many years, according to IEC standard and national standard is main criterion, at the moving steady state parameters of transformer, the initial conditions of comprehensive transformer, running environment, automatically compare, analyze, automatic diagnosis goes out power transformer and bears that moving steady state (SS) has or not deterioration (winding deformation after the short-circuit current rush, displacement and iron core looseness) trend and degradation, and assess the transformer operational reliability according to this, disclose failure cause and judge whether transformer needs whole maintenance or renewal and propose operation, safeguard or the maintenance suggestion, guarantee safe operation of power system with this.

High level diagnostics software will possess comprehensively database management function such as the storage, renewal, inquiry of data, to take into full account the design of telecommunication, resource sharing function simultaneously, integrated for next step online detection, monitoring device of realizing power transformer, advance specifically and realize that electric power information provides technical support.

8 embodiments

8.1 general introduction

Transformer be fail, most important, the most valuable equipment in the change, distribution system, the safe operation of transformer is the safe operation most important thing especially of electric power system the leaders at different levels cardinal task, particularly extra-high-voltage large-capacity transf paid close attention to the most.Owing to the accident rate that transformer is damaged by the impact of short-circuit current is crouched height not down so far, the tracking that peace fortune portion of State Power Corporation requires each province and city Utilities Electric Co. (office) to carry out the moving steady state (SS) of Large and Medium-sized Power Transformer detects, and does one's utmost to reduce the short circuit accident of transformer." CD9882 type transformer moves the steady state parameters tester " that our factory is succeeded in developing under the level science and technology expert of National Electricity Co. instructs arises at the historic moment, and is the strong instrument that power department is implemented the moving steady state (SS) diagnosis of transformer.

This instrument can be surveyed parameters such as transformer impedance drop, short-circuit impedance, short-circuit reactance, leakage inductance, short circuit loss, open circuit loss, no-load current, unloaded equivalent impedance according to the relevant regulations of GB GB1094.5-" power transformer bears the ability of short circuit " (declaration original text) and International Electrotechnical Commission (IEC60076-5:2000) standard under low-voltage.The user can be by all previous measured value longitudinal comparison and each lateral comparison between single-phase, the moving steady state (SS) that the diagnosis transformer bears after the short-circuit current rush has or not deterioration (winding deformation, displacement and core slackness, displacement) trend and degradation, and assess the transformer operational reliability according to this, and then make a decision transformer and whether need the core body maintenance or upgrade, guarantee safe operation of power system.

More than 4 years, this instrument in Xi'an, Shenyang, Baoding, the isallobaric device in Changsha manufacturing plant, study ground such as Gansu, Xinjiang, Shaanxi, Ningxia, Jiangsu, Hunan, Hebei, Henan, Shandong, Liaoning, Jilin, Shanxi, Jiangsu, Guangdong, Guangxi in one's power electric system extensively on probation, surveyed the transformer hundreds of times of 10kV, 35kV, 110kV, 220kV, 330kV, 500kV.All obtain satisfied effect, reach the regulation of " reproducibility that all reactance measurements reach should in ± 0.2% " of GB GB1094.5 regulation fully.And detect the transformer that moves the steady state (SS) deterioration repeatedly, and obtained checking and processing by the core body inspection, avoided the generation of the great burst accident of a lot of harm.

8.2 test event and the key technical indexes

8.2.1 useful trichotomy measures simultaneously, and show automatically and write down following ten values

(1) three-phase voltage: Ua, Ub, Uc

(2) three-phase current: Ia, Ib, Ic

(3) three phase power: Pa, Pb, Pc

(4) supply frequency: F

The back shows and the following value of record 8.2.2 can calculate automatically

(1) three-phase average voltage: Un

(2) three-phase average current: In

(3) the phase-splitting power factor of three-phase: COS Φ a, COS Φ b, COS Φ c

(4) three-phase general power: ∑ P

8.2.3 useful trichotomy measures, also can be converted to each single-phase value and three-phase mean value or the three-phase total value that shows under specified or the agreed terms and write down the following moving steady state parameters of transformer automatically.

(1) impedance voltage (being equal under the rated condition): Uk (%)

(2) short-circuit impedance (being equal under the rated condition): Zk (Ω)

(3) short-circuit reactance (being equal under the rated condition): Xk (Ω)

(4) leakage inductance (being equal under the rated condition): Lk (mH)

(5) load loss (being equal under the rated condition): Pk (kW)

(6) no-load current (under the agreed terms): Ios (mA)

(7) open circuit loss (under the agreed terms): Pos (W)

(8) unloaded equivalent impedance (under the agreed terms): Zos (Ω)

8.2.4 useful single plane method measures, converts, shows, writes down each single-phase moving steady state parameters value of transformer respectively, test event is identical with 8.2.3.

8.3 range ability

8.3.1 basic range

Voltage: 50～500 (V)

Frequency: 45～65 (Hz)

Electric current: 0.006～60 (A)

Power factor: 0.02～1.0

8.3.2 expansion range

Voltage, electric current can extend to required arbitrary value by voltage transformer (VT) (PT) summation current transformer (CT), and other respectively measures this instrument can the automatically corresponding expansion by the multiplying power of mutual inductor.

8.3.3 accuracy of measurement (under standard conditions in the range ability)

Voltage (real effective): 0.2 grade

Electric current (real effective): 0.2 grade

Frequency: 0.1 grade

Impedance voltage: 0.2 grade

Short-circuit impedance: 0.2 grade

Short-circuit reactance: 0.2 grade

Leakage inductance: 0.2 grade

Loss: COS Φ 〉=0.5 o'clock, 0.2 grade

0.5＞COS Φ 〉=0.1 o'clock, 0.5 grade

0.1＞COS Φ 〉=0.02 o'clock, 1.0 grades

Power factor: same loss

8.3.4 service condition environment temperature: 0～40 ℃.There is not macro-corrosion gas on every side.

8.3.5 physical dimension 480 * 380 * 220 (mm).

8.3.6 the heavily about 12kg of weight instrument (comprising annex).

8.4 test function and principal feature

8.4.1 can measuring parameter, the while of the moving steady state (SS) of the sensitive reaction of energy such as transformer impedance drop Uk, short-circuit impedance Zk, short-circuit reactance Xk, leakage inductance Lk winding at the scene with low-voltage (220V/380V) method, this instrument can also measure the parameter that the sensitive reaction iron core of energy such as no-load current Ios, open circuit loss Pos, unloaded equivalent impedance Zos moves steady state (SS).

The requirement to the test instrumentation precision of national standard (GB) and IEC (IEC) is satisfied in the accuracy of this instrument test above-mentioned parameter fully.

8.4.2 this instrument has concurrently single-phase and the three-phase test function, is furnished with the special test line, test connection is very simple and convenient.

8.4.3 this instrument test amount limit for width, the direct test of electric current can be greatly to 60 peaces under the prerequisite of the accuracy that guarantees the 8.3.3 regulation, little of 6 milliamperes, the basic satisfied needs that directly measure the moving steady state parameters of power transformer of each electric pressure, various capacity and the mode of connection with civil power (220V/380V).

8.4.4 this instrument is measuring voltage, electric current, power, power factor, frequency values accurately.And can actual measurement voltage and current real effective under the serious condition that distorts take place at the experiment power supply waveform, can be at the scene as high-grade multi-functional indicating instrument use or as the on-the-spot indicating instrument of standard scale verification.

8.4.5 this instrument can be used for carrying out the no-load test and the load test of various power transformers under rated condition behind voltage transformer (VT) summation current transformer range extension.

8.4.6 this instrument adopts electronic technology, Chinese function menu, and keyboard operation, a plurality of electric weight are sampled simultaneously, carry out data processing automatically, and can carry out tentative diagnosis, and test and diagnostic result directly show on LCD screen, but also real time print.Whole test process is simple and direct lucid and lively.

8.4.7 this instrument is furnished with RS232 interface and bitcom, test result can be defeated by host computer.Set up that database is inquired about, the test report of analysis-by-synthesis, diagnosis and generation standard.

8.4.8 this instrument adopts all aluminium alloy cabinet, integrated design, and volume is little, in light weight, is easy to carry.

8.5 panel each several part function

8.5.1 have 14 membrane keyboards on the panel.Wherein 10 is multiplexing key.

Comprise: 11 of numerical keys: 0～9; (radix point).

13 of function keys:

Print, latch, return, ↑ (moving on the cursor), ↓ (cursor moves down), confirm, be provided with real-time measurement, iron core, three phase windings, single-phase winding, date, reset

8.5.2 input, outlet terminal

11 of current terminals: the 6A and 60A range input terminal, each one of 0.6A single-phase with 0.06A (A mutually) input terminal and three-phase current outlet terminal that are provided with three-phase.

4 of voltage terminals: be provided with three-phase voltage terminals and a zero line (N) terminals.

8.5.3 one of printer.

8.5.4 one of communication interface.

8.5.5 display screen one side.8.5.6 one of brightness of display screen adjustable side.

8.5.7 one of power switch.

8.5.8 one of power supply socket.

9 parameter setting and selections

9.1 initialization

Power switch pushes the ON position, power connection, and tester enters init state, and screen display goes out instrument model, title, manufacturer and telephone number.

9.2 function selecting

In init state, by any key, screen display Chinese master menu.

Have four measurement functions optional:

Measure and on the A screen, show 10 values among the 8.2.1, the value after 6 calculating on B screen among the demonstration 8.2.2.

Iron core measures and demonstrates 4 values that characterize the moving steady state parameters of transformer core.

Three phase windings measure and demonstrate 9 values that detect the moving steady state parameters of three-phase transformer winding with trichotomy.

Single-phase winding is achieved as follows one of corresponding function of two objects according to the selection of B parameter Y:

9.2.1 measure and demonstrate 5 values checking the moving steady state parameters of each single-phase winding of three-phase transformer with single plane method.

9.2.2 measure and demonstrate 8 values of the moving steady state parameters of single transformer winding.

System of selection has two kinds.A kind of is direct by the function key on the instrument panel, and instrument enters corresponding this functional status; Another kind is to use and moves " ↑ " on the cursor or move down " ↓ " key, the cursor on the moving screen, and behind the selected function items, by " affirmation " key, instrument enters the function corresponding state again.

After entering the measurement state, if the screen upper right corner shows locking character " HOLD ", by once " latching " key, character " HOLD " disappears, and instrument begins to measure.

Carry out transformer moving steady state (SS) test need carrying out 9.3 and 9.4 parameter settings that require and parameter selection.

Every measurement of this handbook 8.4.4 regulation and verification all can directly be carried out under " measuring in real time " function.

9.3 parameter setting

Directly parameter setting (SETUP) interface occurs, can carry out following nine parameter settings by " setting " key, screen;

Be powered the tap gear K that presses winding _G

By the tap gear K of short circuit winding _D

Tested winding is at the impedance voltage name plate rating Uke of this tap gear %

Be powered and press winding at the nominal voltage value Uel of this tap gear kV

Transformer capacity Sn kVA

Warm Tm ℃ of transformer upper strata oil during test

The about definite value Uset V of test voltage

Voltage transformer (VT) (PT) no-load voltage ratio

Current transformer (CT) no-load voltage ratio

Method of operating is: moving " ↑ " or moving down " ↓ " on cursor key on the screen, behind selected certain parameter item that will be provided with, by " affirmation " key, this original parameter disappears, press numerical key (0～9) again, re-enter parameter, after the defeated parameter of affirmation institute is accurate, by " affirmation " key, defeated parameter preserves.If data are inputed by mistake, need change, press once " affirmation " key again, original parameter disappears automatically, imports new data again, by " affirmation " key, preserves new data.After this parameter input finishes, if also need to change other parameter, use the selected parameter item that will change of cursor key, operating process is identical with said process.After the parameter input finished, by " returning " key, program turned back to original functional status.

9.4 parameter is selected

After the parameter setting, press once " setting " key again, screen parameter occurs and selects (SELECT) interface, just can carry out parameter and select.

Under other state, continuously by twice " setting " key, screen parameter also can occur and select (SELECT) interface, can carry out following seven parameters and select:

Transformer pattern BY:1 (single-phase)/3 (three-phase)

The tested winding of transformer is to HML: high centering (H-M) or high to low (H-L) or in to low (M-L)

Winding is tested separate Nr: three-phase (OABC/ABC) or single-phase (A0/B0/C0) or alternate (AB/BC/CA)

Iron core is tested separate Nt:a-bc/b-ca/c-ab, a-b/b-c/c-a, a-x/b-y/c-z

Transformer coil material coefficients R s: the copper material coefficient is 235; The aluminium coefficient is 225

Cn:75 ℃ or 80 ℃ or 95 ℃ or 100 ℃ or 120 ℃ or 145 ℃ or 170 ℃ of reduction temperature

The electric current gear Icw:60A shelves of this testing tool or 6A shelves or 0.6A shelves or 0.06A shelves 60A/6A/0.6A/0.06A)

Method of operating is: moving " ↑ " or moving down " ↓ " on the use cursor key on the screen, behind selected certain parameter item that will change, continuously by " affirmation " key, the optional amount circulation of this parameter item shows, after the selected required amount, stop by " affirmation " key, parameter is selected to finish.If also need to reelect other a certain parameter, continue to make an accurate selection of a certain parameter item that will rewrite with cursor key, operating process is identical with said process.After parameter was selected to finish, by " returning " key, program turned back to original functional status.

9.5 date time setting method

Press " date " key, year, month, day, hour, min, second that screen display is current earlier.

If need change date, time parameter,, can carry out resetting of year, month, day, hour, min, second again by " setting " key.Method to set up is identical with 9.3 parameter setting methods.Setting completed, and by " returning " key, program turns back to former function.

Attention: selection or all parameters that are provided with must be corresponding one by one with actual conditions.

10 test operations

10.1 operating instruction

Before 10.1.1 instrument is charged, require this tool housing must ground connection good (this instrument trailing flank is provided with earth terminal).

10.1.2 operation steps: after confirming that on inspection all wiring are errorless, connect earlier the working power AC220V of instrument, start preheating 15 minutes can the call through test power supply, begins to test; Behind to be tested the finishing, must cut off experiment power supply earlier, and then close the instrument working power.Otherwise may damage instrument.

10.1.3 in test process, if instrument keyboard (button is inoperative) out of control is pressed " resetting " key, instrument reenters initialization (initialization procedure is seen 9.1 joints).After perhaps cutting off experiment power supply earlier, start again after the shutdown, instrument enters initialization automatically.

10.1.4 on-the-spot test should be noted following 2 points:

(1) tests the preceding necessary required power supply capacity Ss of estimating test electric current I s, and check the rated capacity SH and the rated current IH of on-the-spot power supply.

(2) test loop will be provided with current-limiting protection device, if there is short trouble in tested transformer inside, current-limiting protection device should be able to immediately move during energized, cuts off the electricity supply.

Attention: protection (the containing fuse) definite value of checking power supply.Whenever never allow to push away the used power supply of electric substation.

10.2 basic parameter actual measurement

Press " actual measurement " key on the instrument, enter basic parameter (seeing 8.2.1 and 8.2.2) actual measurement.

Before carrying out the basic parameter actual measurement, check wiring earlier, and must satisfy following provisions:

10.2.1 before carrying out testing current, should estimate tested current value earlier and whether exceed 60A.If exceed, test after need connecing current transformer, simultaneously the CT value in current transformer ratio (K) the value change instrument parameter setting option that should insert according to reality.If do not exceed 60A, can directly test.At this moment, should the CT value be set to 1.This instrument panel is provided with 60A and two groups of three-phase current terminals of 6A, and 0.6A and 0.06A single-phase current terminals each one (A mutually) require actual terminals that use on the panel consistent with parameter in the instrument parameter setting option (60A/6A/0.6A/0.06A).If the measuring current value is difficult to estimation, at first insert the 60A shelves, and determine that according to the examination measured value whether needs are changed, the examination measured value is during less than 6A, should change to the 6A shelves and test; The examination measured value in single-phase when test is during less than 0.6A (or 0.06A), should change to the terminals of 0.6A (or 0.06A) shelves and survey.

10.2.2 voltage range is below 500V, in the time of need not using PT, voltage transformer (VT) (PT) value is set to 1 earlier, and when needs expanded voltage range, earlier that no-load voltage ratio (K) is suitable voltage transformer (VT) inserted, and the PT value on the instrument is set to K.

Single-phase 10.2.3 (containing alternate) test: be to improve the reproducibility of test, the A that single-phase test must be connected on this instrument carries out on mutually.No matter test transformer A phase, B phase, C phase (should be arranged to accordingly when test phase Nr or Nt are set A0, B0, C0 ...), the wiring on instrument requires to import termination power mutually from the A of electric current all the time, and connects test specimen from the A phase output terminal of electric current; Voltage is received voltage output end A on the instrument mutually and between the zero line N (being that Ua, N hold).

10.3 iron core moves steady state parameters (hereinafter to be referred as the iron core parameter) test

Press " iron core " key on the instrument, enter the iron core parameter testing.

Before carrying out the iron core parameter testing, check that wiring must satisfy the requirements of 10.2 joints, also will be, test separate Nt etc. and be provided with and select (for details, see the appendix 1) or examine to the combination form BY (three-phase or single-phase) of transformer, transformer separate unit rated capacity (Sn), transformer making alive side winding nominal voltage (Ue), the about definite value of test voltage (low decide voltage).

Identical on the connection principle of the wiring of transformer core parameter testing and the single-phase no-load test of transformer.

10.4 winding moves steady state parameters (hereinafter to be referred as winding parameter) test

Press " winding " key on the instrument, enter the winding parameter test.

Before carrying out the winding parameter test, check wiring, must satisfy the requirement of 10.2 joints, the tap gear KG of the warm Tm of transformer upper strata oil in the time of also will be, reduction temperature Cn, the testing transformer material coefficients R s of transformer, the tested winding of transformer pressurized winding during to HML, test and be provided with and select (for details, see the appendix 1) by parameters such as the tap gear KD of short circuit winding, the separate Nr of test to the nominal voltage value Ue of the separate unit rated capacity Sn of the combination form BY (three-phase or single-phase) of transformer, transformer, the pressurized winding of transformer, test, or examine.

The connection principle of the winding parameter test of transformer is identical with the wiring of transformer load test.

The test and diagnostic of 11 winding parameters

11.1 the program of test and diagnosis

11.1.1 basic test

The basic test of three-phase transformer winding parameter carries out with trichotomy.

The basic test of three-phase transformer group winding parameter carries out with single plane method each single transformer respectively.

The project of basic test then by winding (to) number and following minimum requirement arranged.

11.1.1.1 the transformer of two windings (promptly a winding to) should carry out following twice test at least:

(1) the specified shelves at the high pressure winding pressurize short circuit low pressure winding.

(2) the ceiling voltage shelves at the high pressure winding pressurize short circuit low pressure winding.

11.1.1.2 the transformer of three windings (promptly three winding to) should carry out following three tests at least:

(1), presses winding (if middle pressure winding has shunting switch, should at specified gear short circuit) in the short circuit, low pressure winding open circuit in the specified shelves pressurization of high pressure winding.

(2), press winding (if middle pressure winding has shunting switch, should at ceiling voltage gear short circuit) in the short circuit, low pressure winding open circuit in the pressurization of the ceiling voltage shelves of high pressure winding.

(3) the specified shelves at the high pressure winding pressurize short circuit low pressure winding.The middle winding open circuit of pressing.

11.1.1.3N the transformer of winding (that is: N (N-1)/2 winding to) should carry out following N test at least earlier.That is: at specified shelves, the high pressure winding to each test of other winding once; The winding of band shunting switch must once be tested at least at the ceiling voltage shelves again

Specify: have certain to intend pressurization winding ceiling voltage gear impedance voltage value if mark on the transformer nameplate some other windings, or during the existing initial value of this impedance voltage value, this can omit in the test of rated voltage shelves winding and not do, and only does the test under the ceiling voltage gear.General purpose is to allow all circles of all windings all be detected.

11.1.2 tentative diagnosis

After basic test projects are all finished, if OK occurs on the instrument display screen, the moving no abnormal discovery of steady state (SS) of expression winding.This winding parameter test of this TV station transformer leaves it at that.If the unusual project of the general reply appearance of demonstration " WARN " is carried out repetition measurement 1-2 time on the display screen, to confirm or the eliminating accidentalia.After confirming that test result is credible, the three-phase transformer group is carried out comprehensive analysis and diagnosis.Then should carry out doing analysis-by-synthesis and diagnosis after the follow-up test to three-phase transformer.

11.1.3 follow-up test

In basic test,,, also must carry out follow-up single-phase test as long as there is a test result unusual for three-phase transformer.

The follow-up test project is all carried out with single plane method, should comprise at least:

(1) the unusual right single-phase parameter testing of winding of winding.

(2) with unusual winding to the single-phase parameter testing of the right winding of relevant winding.

11.1.4 analysis-by-synthesis and diagnosis

After all tests (containing the follow-up test of three-phase transformer when unusual) are finished, should carry out analysis-by-synthesis.The most important method of analysis-by-synthesis is that all previous measured result is carried out longitudinal comparison accordingly, and each measured result is carried out three-phase lateral comparison to each other, also will carry out in conjunction with ruuning situation and other test result as much as possible.Afterwards, should provide clear and definite diagnosis, and propose suggestion operation, detection or maintenance.

11.2 test wiring

11.2.1 general requirement

The wiring of test winding parameter is same as the transformer load test on principle.That is: the opposite side short circuit is pressed in the right side additional examination electrical verification of tested winding.Generally speaking, trial voltage is added in high pressure (H) or middle pressure (M) side, presses (M) or low pressure (L) side in the short circuit.

Concrete wiring divides three-phase transformer and three-phase transformer group (promptly being formed by three separate single-phase transformers combinations) slightly different because of power transformer; Wherein, three-phase transformer is looked pressurized winding neutral point again and is had or not sleeve pipe to draw and different.But all must defer to following basic demand:

(1) when test current estimated value Is＜6A, power supply directly inserts the electric current 6A input end of instrument; When 6A＜Is＜60A, power supply directly inserts the electric current 60A input end of instrument; When test current estimated value Is＞60A, should select no-load voltage ratio suitable current mutual inductor according to the estimated value of Is, the secondary current of mutual inductor is inserted the electric current 6A input end of instrument.

When (2) using this instrument to carry out single-phase (containing alternate) test, no matter test which phase or any two-phase, all must insert UA, IA and the N end of instrument A phase and test, and note selecting for use the 6A or the 60A current input terminal of A phase according to the size of current IS.

11.2.2 make up the three-phase transformer group that forms by three single transformers

With single plane method each single transformer is tested separately.Wiring is with reference to (this figure is only corresponding to surveying the B phase transformer) shown in Figure 4.

As electric current estimated value Is during, then should insert 6A (no matter survey which phase of transformer, all use the A phase of the instrument) shelves of this instrument by current transformer (CT) greater than 60A.Wiring is with reference to Fig. 5 (this figure is only corresponding to surveying the B phase transformer).

11.2.3 be powered the three-phase transformer (is the Y0 wiring as high, middle pressure winding) that pressure winding neutral point has sleeve pipe to draw.

11.2.3.1 three-phase test

With three-phase and four-line (OABC) method.Wiring is seen shown in Figure 6;

As electric current estimated value Is during, then should insert the 6A shelves of this instrument by current transformer (CT) greater than 60A.Wiring is seen shown in Figure 7;

11.2.3.2 single-phase test

Directly survey the winding parameter of A0, B0, C0 successively.Wiring is with reference to shown in Fig. 8 (this figure is only corresponding to surveying BO);

When electric current estimated value＞60A, applied current mutual inductor range extension, wiring is with reference to Fig. 9 (this figure is only corresponding to surveying BO);

There is not the three-phase transformer (is Y, Δ wiring as high, middle pressure winding) that sleeve pipe is drawn 11.2.4 be powered pressure winding neutral point

11.2.4.1 three-phase test

With phase three-wire three (ABC) method.Wiring is seen shown in Figure 10;

In fact, do not have sleeve pipe in the pressurized winding neutral point of tested transformer and draw, Figure 10 compares with Fig. 6, lacked a 0N line with 0 mutually ground connection change into N ground connection.

As electric current estimated value Is during, then should insert the 6A shelves of this instrument by current transformer (CT) greater than 60A.Wiring is carried out with reference to Fig. 7 and Figure 10.

11.2.4.2 single-phase test

Survey the winding parameter of AB, BC, CA (therefore also often being called as alternate test) successively.Wiring is with reference to shown in Figure 11 (this figure is only for surveying BC):

When electric current estimated value Is＞60A, applied current mutual inductor range extension, wiring is carried out with reference to Fig. 8 and Figure 11.

11.3 method of testing and test result

Correctly finish all wiring and errorless on inspection after, open power switch device, connect instrument power source.

11.3.1 parameter setting and selection

Each time actual measure data before, all must to the input instrument following parameter reset and select (contain and check and change).The parameter of selecting or being provided with must be corresponding one by one with actual conditions and tested object.

11.3.1.1 (accurately keying in corresponding digital) checked or reset to following eight parameters:

Tested winding is to the impedance voltage name plate rating Uke:% under this tap gear

Be powered the tap gear KG that presses winding:

[, keying in " 0 "] as if no name plate rating under no tap or this gear

By the tap gear KD of short circuit winding:

The nominal voltage value Ue:kV of pressurized side winding when this tap gear

Transformer capacity Sn:kVA

The warm Tm of transformer upper strata oil during test: ℃

Voltage transformer (VT) (PT) no-load voltage ratio

Current transformer (CT) no-load voltage ratio

11.3.1.2 following six parameters are checked or are reselected:

The pattern BY of transformer: single-phase or three-phase

The tested winding of transformer is to (HML): high centering or high to low or in to low (H-M/H-L/M-L)

Test separate Nb: three-phase single-phase or alternate (OABC/ABC/A0/B0/C0/AB/BC/CA)

Transformer coil material coefficient (Rs): the copper material coefficient is 235; The aluminium coefficient is 225

Reduction standard temperature Cn: oil-filled power transformer is made as 75

Instrument electric current gear Icw:60A shelves or 6A shelves (60A/6A)

11.3.2 the data of measuring

After wiring and parameter are provided with and select correctly on inspection, the call through test power supply.By " three phase windings " key, or " single-phase winding " key, after also can in master menu, making an accurate selection of item, by " affirmation " key, test beginning, test value update displayed continuously on display screen is behind the value stabilization to be tested (connect usually testing power supply about 10 seconds), by " locking " key, can obtain test data.

11.3.3 show and the printing test result

11.3.3.1 single transformer winding parameter test shows and the data that print comprise:

BY 1 (single transformer)

The tested transformer capacity of Sn (kVA)

The Nr test is separate;

KG is powered the tap gear of pressing winding;

KD is by the tap gear of short circuit winding;

UH is powered and presses the nominal voltage value (kV) of winding at this tap gear;

The real effective of Us test voltage (V);

The real effective of Is measuring current (Is);

The power (W) of Pks actual measurement

The name plate rating of Uke impedance voltage (%);

The impedance voltage value (%) of this actual measurement of Uk;

The relative deviation of Δ Uk Uk and Uke (%);

The short-circuit impedance value (Ω) of this actual measurement of Zk;

The short-circuit reactance value (Ω) of this actual measurement of Xk;

The leakage inductance value (mH) of this actual measurement of Lk;

Rs material coefficient;

The no-load voltage ratio value of CT current transformer (as should be 1.000) for directly testing this value;

Cn reduction temperature;

Transformer upper strata oil temperature during the Tm test.

11.3.3.2 three-phase transformer winding parameter basic test shows and the data that print comprise:

BY 3 (three-phase transformer)

The tested transformer capacity of Sn (kVA)

The Nr test is separate;

The tested winding of HML is right;

KG is powered the tap gear of pressing winding;

KD is by the tap gear of short circuit winding;

The UH transformer is powered presses the nominal voltage of winding at this tap gear;

The mean value that adds the three-phase voltage real effective during Us test;

The mean value of Is three-phase measuring current real effective;

The general power (W) of Pks actual measurement

The name plate rating of Uke impedance voltage (%);

The impedance voltage value (%) of Uk actual measurement;

The relative deviation (%) of Δ Uk Uk and Uke (%);

The short-circuit impedance (Ω) of Zka, Zkb, Zkc A phase, B phase, C phase;

The maximum mutual deviation of each single-phase short circuit resistance value of Δ Zmax (maximal value subtracts the difference of minimum value divided by minimum value);

Rs material coefficient;

The no-load voltage ratio value of CT current transformer (as should be 1.000) for directly testing this value;

Cn reduction temperature;

Transformer upper strata oil temperature during the Tm test.

11.3.3.3 the single-phase test that the three-phase transformer winding parameter is follow-up shows and the data that print comprise:

The Nr test is separate;

BY 3 (in the three-phase transformer)

The tested transformer capacity of Sn (kVA)

The tested winding of HML is right;

KG is powered the tap gear of pressing winding;

KD is by the tap gear of short circuit winding;

Ue is powered and presses the nominal voltage (kV) of winding when this tap gear;

Alive real effective (V) during the Us test;

The real effective of Is measuring current (A);

The short-circuit reactance value (Ω) of the tested phase of Xka (Xkb, Xkc);

The leakage inductance value (mH) of the tested phase of Lka (Lkb, Lkc);

The no-load voltage ratio value of the outer attached current transformer of CT (as should be 1.000) for directly testing this value.

Annotate: because the data presented project is many, single screen can't show fully, so adopt the double screen display mode.The user can check by carrying out page turning by " ↑ " or " ↓ " key.

11.4 tentative diagnosis

11.4.1 in the basic test result (seeing 11.3.3) who demonstrates, (single transformer of three-phase transformer group is followed successively by Δ Uka, Δ Ukb, Δ Ukc as if Δ Uk; Three-phase transformer also has Δ Zmax) all less than 2%, character " OK " will appear in the instrument screen upper right corner.This winding of representing tested transformer is to no abnormal at this gear.

By the requirement of 3.1.1 (two-winding transformer is surveyed secondary, and three-winding transformer is surveyed three times ...) test finishes all no abnormal discovery, i.e. decidable: the moving steady state (SS) of this Transformer Winding is normal!

Tentative diagnosis after the basic test project is finished is carried out with regard to test result automatically by this instrument.

11.4.2 if a certain winding of tested transformer is to occurring one and above greater than 2% in the Δ Uk of a certain gear or Δ Zmax, character " WARN " will appear in the screen upper right corner.Also should carry out follow-up single-phase test to three-phase transformer.

Prompting: occur checking earlier unusually whether the parameter of all selections and setting is entirely true, whether whether complete requirement, especially short circuit according to this handbook meets the requirements in wiring.If affirmation is errorless, should carry out 1～2 retrial again to the above-mentioned project that surpasses warning value, if the phase mutual deviation of each corresponding test value shows that then test result is normally believable in ± 2 ‰.

11.5 analysis-by-synthesis

11.5.1 about the relevant regulations of rules and expert authority's suggestion

(1) whether national standard (GB1094.5) and IEC (IEC) regulation exceed standard to judge after transformer bears the short-circuit current rush test whether displacement or distortion are arranged with the variation of reactance value.

(2) State Power Corporation's regulation has or not significant change to judge that transformer in service suffers behind the sudden short circuit non-fault to be arranged with low-voltage short-circuit impedance value.

(3) impedance voltage (Uk) also is the important parameter of reflection winding construction, is that manufacturing plant is printed on the main significant technical parameter on each transformer nameplate before dispatching from the factory after test.

(4) theoretically, leakage inductance between two windings (Lk) is the direct function of relative position between two windings, and have the transformer expert to think on the relevant document of delivering and in the speech detecting leakage inductance is the most direct, the most effective for diagnosing winding that non-displacement, distortion are arranged.

Because above-mentioned four parameters (Uk, Zk, Xk, Lk) that can react the moving steady state (SS) of Transformer Winding are the function of relative geometry position between each winding centering two winding of transformer, different physical meaning is arranged again, therefore, the variation of these parameters of analysis-by-synthesis, it is useful for definite transformer the order of severity of zero defect, defective and position being arranged.

11.5.2 the longitudinal comparison of all previous test data

(vertical than) is that the diagnosis transformer bears after the short-circuit current rush the moving steady state (SS) of winding and has or not deterioration, technological means the most intuitively because the relatively relative variation of the moving all previous test data of steady state parameters of winding.Therefore, 2 is very important below.

(1) sets up the database that every transformer moves the source book archives of steady state parameters and gathers all previous test result, wherein the particularly important is before dispatching from the factory and twice measured data before putting into operation.

(2) as far as possible intactly measure the total data (comprising) that transformer moves steady state parameters under the condition that the time allows at the scene with trichotomy and single plane method.At least for the first time the moving steady state parameters of test should be complete each winding that measures this transformer to moving steady state parameters at the single-phase and three-phase of specified shelves and ceiling voltage shelves.

11.5.3 note

(1) a certain winding between above-mentioned four parameters unusual, cause if be strictly the distortion of a certain winding or displacement institute, will inevitably cause the ANOMALOUS VARIATIONS of other relevant winding to above-mentioned four parameters.Therefore, test should further detect the right parameter of associated winding when noting abnormalities, and is that displacement or distortion have taken place which phase winding of which side to help making a definite diagnosis.

(2) Transformer Winding deform and displacement as a rule three-phase be inconsistent, therefore, it is significant for definite fault mutually that the moving steady state parameters (horizontal ratio) of right each of unusual winding between single-phase relatively arranged, but more direct be vertical the ratio.And the deterioration that above-mentioned four parameters are moved steady state (SS) to the reflection Transformer Winding is identical on direction, and basic synchronization changes.

11.5.4 contingency influence factor

Because the criterion of the moving steady state parameters of winding only is a percentile, and to the requirement of Meter Test precision in thousand fractiles, even therefore wiring is entirely true, the setting of parameter and selection are also entirely true, and following five factors still may make precision of test result and credibility be affected.

(1) flickering of line voltage and highlighting property harmonic wave in short-term.

Power supply three-phase voltage phase angle and amplitude were unbalanced when (2) three-phase was tested, and caused the neutral point potential drifting.

(3) well whether the short circuit of shorting stub.Comprise that the sectional area of shorting stub is too little or the junction contact is not tight.

(4) instrument periodic check not.

(5) test loop and tested transformer have not clear defective.

11.6 criterion and countermeasure (suggestion)

11.6.1 the vertical ratio of single-phase parameter

(three-phase transformer contains Xk, Lk to the arbitrary single-phase winding parameter of arbitrary tap gear that arbitrary winding of transformer is right; Single transformer contains Uk, Zk, Xk, Lk).The data that recorded with raw data or last time differ (vertical poor) greater than 2%, and promptly should be considered as moving the stablizing of winding has unusually.

Should take corresponding technical measures.As: strengthen to detect, the possibility that the restriction external short circuit takes place, the size and the duration of short-circuit current, arrange the core body inspection between in due course;

If the vertical difference of above-mentioned parameter is greater than 5%, promptly the decidable transformer has major defect, should not continue to add operation of power networks.

11.6.2 the horizontal ratio of single-phase parameter

As long as three single-phase winding parameters ratio each other of a certain tap gear that a certain winding of transformer is right, there be one group (Xk, Lk) to differ by more than 2% or at 5% o'clock, can treat with 11.6.1.

11.6.3 the vertical ratio of the triphase parameter of three-phase transformer winding

The impedance voltage (Uk) of a certain tap gear that a certain winding of three-phase transformer is right and raw data or the data that recorded last time differ by more than at 2% o'clock, all tackle this winding to with this winding to relevant winding to carrying out single-phase test, so that further make a definite diagnosis.Do not get rid of the incorrect possibility of name plate rating.

It may be noted that: pressurized winding neutral point does not have the right three-phase test data of winding that sleeve pipe is drawn, and reliability is relatively poor relatively, must more pay attention to processing and analysis to single-phase test data.As previously mentioned, pressurized winding neutral point does not have the right single-phase test data of winding that sleeve pipe draws and is actually alternate test data, carries out analysis-by-synthesis and diagnosis after therefore must being broken down into very single-phase data earlier.

This instrument is furnished with multiple functional software, can carry out complete data processing, analysis-by-synthesis and condition diagnosing in host computer.And the test report of generation standard.

Need explanation: load loss Pk has auxiliary reference role for the moving steady state (SS) of diagnosis winding, and attempt obtains load loss value accurately, must directly hinder winding and carry out temperature conversion, the temperature of the direct current resistance that for this reason need import each winding when testing.The diagnostic software that can utilize this instrument to join finishes this function at host computer.

Claims (2)

1, meets specified test and diagnostic software in " CD9882 type transformer moves steady state parameters tester operation manual ".

2, the circuit theory diagrams and the Single Chip Microcomputer (SCM) program of " CD9882 type transformer moves the steady state parameters tester ".

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