CN104237758B - A kind of UHV impulse voltage endurance test method based on scale model - Google Patents
A kind of UHV impulse voltage endurance test method based on scale model Download PDFInfo
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- CN104237758B CN104237758B CN201410538759.5A CN201410538759A CN104237758B CN 104237758 B CN104237758 B CN 104237758B CN 201410538759 A CN201410538759 A CN 201410538759A CN 104237758 B CN104237758 B CN 104237758B
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- 238000010998 test method Methods 0.000 title claims abstract description 13
- 238000012360 testing method Methods 0.000 claims abstract description 63
- 238000004804 winding Methods 0.000 claims abstract description 39
- 238000011160 research Methods 0.000 claims abstract description 13
- 238000009826 distribution Methods 0.000 claims abstract description 12
- 238000000605 extraction Methods 0.000 claims abstract description 11
- 238000004088 simulation Methods 0.000 claims abstract description 10
- 238000004458 analytical method Methods 0.000 claims abstract description 9
- 238000013461 design Methods 0.000 claims abstract description 8
- 230000005611 electricity Effects 0.000 claims description 9
- 230000007935 neutral effect Effects 0.000 claims description 8
- 238000005070 sampling Methods 0.000 claims description 6
- 238000005259 measurement Methods 0.000 claims description 3
- 238000012546 transfer Methods 0.000 claims description 3
- 230000004888 barrier function Effects 0.000 claims 1
- 239000011159 matrix material Substances 0.000 claims 1
- 238000002474 experimental method Methods 0.000 abstract description 4
- 230000001419 dependent effect Effects 0.000 abstract 1
- 230000005540 biological transmission Effects 0.000 description 5
- 238000000034 method Methods 0.000 description 5
- 238000009413 insulation Methods 0.000 description 4
- 238000003745 diagnosis Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000010276 construction Methods 0.000 description 1
- 238000009863 impact test Methods 0.000 description 1
- 238000011173 large scale experimental method Methods 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 238000005549 size reduction Methods 0.000 description 1
- 230000001052 transient effect Effects 0.000 description 1
- 230000000007 visual effect Effects 0.000 description 1
Abstract
A kind of UHV impulse voltage endurance test method based on scale model, according to based on the scale model concrete structure contracted than Design Theory, carries out simulation study and obtains the distributed constant of scale model winding, determine test waveform；According to research needs, scale model arranges extraction tap and obtains required test waveform, and dependent failure can be set；Make physical device, utilize scale model to test, be adjusted obtaining required test waveform to the power-supply device parameter made；Simplify device structure and test method, obtain winding voltage distribution waveform, and can be by arranging tap setting corresponding failure research experiment；Obtain the winding normal condition under surge voltage and the voltage's distribiuting characteristic under failure condition by analysis and research, utilize scale-relation to obtain the voltage's distribiuting characteristic of UHV.The present invention can simplify test procedure, reduces experimentation cost, shortens the test period, and can study the winding voltage distribution character in the case of different faults.
Description
Technical field
The present invention relates to aspects of UHVDC equipment test field, a kind of extra-high voltage based on scale model is changed
Convertor transformer impulse voltage endurance test method.
Background technology
In recent years, a plurality of extra high voltage direct current transmission line builds up and puts into operation, and the most a plurality of DC power transmission line is planned, with
Time also research higher voltage grade extra-high voltage direct-current transmission technology.As one of visual plant in DC transmission engineering,
Stability and the reliability of UHV have vital work to the safe operation of whole DC transmission system
With.
Before putting into operation, according to standard-required, UHV must carry out impact test at the scene.Extra-high
The technical merit of pressure converter power transformer is high, and manufacturing process is complicated, and electric pressure is high, and the difficulty carrying out at the scene testing is high, and
Entrance potential waveform and neutral point current waveform can only be obtained, it is impossible to the bulk properties of converter power transformer under Impulse Voltage
Study, once go wrong, be difficult to search its concrete reason, need test key technology is studied.
But, if using large-scale experiment equipment to study, cost is high, and is difficult to obtain required correlation test number
According to, there is no correlation test data, be difficult to again improve experimental technique.Reduce experimentation cost, shorten the test product manufacturing cycle, measure and obtain
Reasonably correlation test data, the impulse withstand voltage experimental study to converter power transformer is significant.
Summary of the invention
It is an object of the invention to, it is provided that a kind of UHV impulse withstand voltage test side based on scale model
Method, the equipment electric pressure needed for this scale model test reduces, and can simplify test procedure, reduces experimentation cost, shortens test
Cycle, and the winding voltage distribution character in the case of different faults can be studied, provide foundation for fault diagnosis and insulating Design.
For solving above-mentioned technical problem, the technical solution used in the present invention is:
A kind of UHV impulse voltage endurance test method based on scale model, comprises the steps:
Step one, according to based on the scale model structure contracted than Design Theory, to inner coil configuration modeling and simulating, obtains
The distributed constant of the electric capacity of scale model winding, inductance and resistance, loop built by the testing equipment then simulating reality, by adjusting
Whole voltage source capacitance parameter and resistance parameter obtain required test waveform；
Step 2, arranges multiple extraction tap to obtain required test waveform on scale model；
Step 3, requires to make actual main capacitance C according to emulation gained distributed constant and design1, wavefront resistance R1, put
Electricity resistance R2, sampling resistor R3, connect composition test loop, according to test waveform, capacitance parameter and the resistance of test loop joined
Number is adjusted, and finally gives required test waveform；
Step 4, after determining surge voltage source dates, tests under low-voltage-grade, first measures under surge voltage
Each draws the voltage's distribiuting characteristic of tap；Utilize arrange to draw the failure condition that tap simulation is different, obtained by test
Voltage waveform and neutral point current waveform, the winding in the case of analysis and research typical fault on internal winding in the case of typical fault
Voltage's distribiuting characteristic and winding transfer function characteristics, be analyzed with simulation result simultaneously；
Step 5, obtains the winding normal condition under surge voltage and the voltage's distribiuting under failure condition by analysis and research
Characteristic, utilizes scale-relation to be back-calculated to obtain the voltage's distribiuting characteristic of UHV.
Further, main capacitance C1, spark gap G, wavefront resistance R1 and discharge resistance R2 be sequentially connected in series, wavefront electricity
The node of resistance R1 and discharge resistance R2 through resitstance voltage divider ground connection, the source side winding of UHV scale model with put
Electricity resistance R2 is connected in parallel, and UHV scale model arranges the extraction tap being connected with the equipment of measurement, extra-high voltage
The neutral point sampled resistance R of converter power transformer scale model3Ground connection.
Further, the tap of drawing arranged is utilized to simulate different failure conditions particularly as follows: utilize the extraction arranged to take out
Connector analog earth fault, utilizes and draws the short trouble that the simulation of tap combination of two is different.
Further, described short trouble includes turn-to-turn short circuit, all over the ground short circuit.
There is advantages that
With directly carry out UHV impulse withstand voltage test to its insulating properties test assessment compared with, the present invention
Use scale model to carry out impulse withstand voltage test, its insulating properties be estimated test, cost can be reduced, shorten the cycle,
And it is obtained in that the voltage's distribiuting characteristic of each winding under the surge voltage normally and under failure condition, can be extra-high voltage converter
Fault diagnosis under transformator surge voltage provides foundation；Owing to scale model volume is little, electric pressure is low, test loop element
Configuration simplifies, and test adjustment is convenient, therefore can also reduce the cost of test, and obtain what master mould test can not obtain
Test data.
Accompanying drawing explanation
Fig. 1 is the wiring diagram of present invention UHV based on scale model impulse voltage endurance test method；
Fig. 2 is master mould typical coil head end time domain voltage distribution waveform；
Fig. 3 is scale model typical coil head end time domain voltage distribution waveform of the present invention.
Detailed description of the invention
Below in conjunction with the accompanying drawing in the present invention, the technical scheme in the present invention is clearly and completely described.
Fig. 1 is the wiring diagram of UHV impulse withstand voltage based on scale model test, wherein C1It it is main electricity
Hold, R1For wavefront resistance, R2For discharge resistance, R3For sampling resistor.G is spark gap, main capacitance C1, spark gap G, wavefront
Resistance R1 and discharge resistance R2 is sequentially connected in series, the node of wavefront resistance R1 and discharge resistance R2 through resitstance voltage divider ground connection,
The source side winding of UHV scale model is connected in parallel with discharge resistance R2, and mould is compared in UHV contracting
Type arranges the extraction tap being connected with the equipment of measurement, the neutral point sampled resistance R of UHV scale model3Connect
Ground.
Resitstance voltage divider is used for measuring High Voltage Impulse Waveform, and the extraction tap of UHV scale model connects survey
Amount equipment to carry out data acquisition, sampling resistor R3For measuring neutral point current.
In the present embodiment, the converter power transformer with model as ZZDFPZ-405200/500-400 as object of study, use with
Lower step carries out pressure test research.
Step one, according to based on contracting than the scale model of UHV of Design Theory, the net of scale model
The structural parameters of side winding and valve side winding are as shown in table 1, its source side winding is different according to shielding mode and winding technique not
With being divided into 5 classes.
Utilize simulation software ANSOFT to establish 2D model and calculate the distributed constant of the electric capacity of its winding, inductance and resistance,
Main capacitance C is set up in electromagnetic transient simulation software PSCAD1, wavefront resistance R1, discharge resistance R2, sampling resistor R3And distribution
The simulation test loop that parameter network collectively forms, replaces spark gap with perfect switch G, emulates it.Set up herein
Scale model scale factor be 1/5, i.e. basic length and width size reduction is 1/5 size of master mould, according to contracting ratio principle, impact
The frequency of waveform to adjust accordingly, and such as, standard lightning impulse voltage is 1.2/50 μ s, then scale model test impact in period electricity
Pressure is 0.24/10 μ s.It is by adjusting C herein1、R1、R2And R3Obtain required waveform.Test surge voltage ripple is not herein
The surge voltage ripple of standard, but carry out corresponding proportion according to the scale-relation of scale model and adjust the waveform of gained.
Table 1 scale model winding parameter
Step 2, according to the winding characteristic of this scale model, its source side winding falls into 5 types, and valve side is helix windings, at net
Side each class winding arranges two and draws tap, and valve side arranges 5 the most altogether and draws tap, arranges altogether 15 and draws tap,
The voltage waveform of the dissimilar winding with diverse location can be obtained, and different faults situation can be combined into, such as, line is set
Circle to earth fault, and the shorted-turn fault etc. of winding adjacent windings, it is simple to follow-up researchs and analyses.
Step 3, requires to make actual main capacitance C according to emulation gained distributed constant and design1, wavefront resistance R1, put
Electricity resistance R2, sampling resistor R3, utilize scale model to carry out preliminary experiment, according to test waveform to main capacitance, wavefront resistance and putting a little
Resistance is adjusted, and finally gives required test waveform, and its error with reference waveform is in allowed band；
Step 4, after determining surge voltage source dates, under low-voltage-grade, (such as 10kV) tests, it is ensured that do not damage
The insulation of bad scale model.First the voltage's distribiuting characteristic of each extraction tap under surge voltage is measured；Utilize the extraction arranged
Tap analogue ground fault, utilizes that to draw the tap combination of two different short trouble of simulation (such as turn-to-turn short circuit, the shortest
Road), obtain in the case of typical fault voltage waveform and neutral point current waveform, analysis and research typical case on internal winding by test
Winding voltage distribution character under failure condition and winding transfer function characteristics, be analyzed with simulation result simultaneously.Really
After determining surge voltage source dates, owing to electric pressure is low, it is not necessary to multistage capacitances in series is discharged, only need a main capacitance, simplify
Test loop.Mainly research builtin voltage distribution character, provides reference for winding construction optimization and insulation safety nargin,
Not being that insulation is examined, so need not, according to impulse withstand voltage test standard, the most partly press impact, carrying out
The steps such as total head impact, can directly test by the unified voltage in insulation tolerance range.
Step 5, obtains the winding normal condition under surge voltage and the voltage's distribiuting under failure condition by analysis and research
Characteristic, utilizes scale-relation to be back-calculated to obtain the voltage's distribiuting characteristic of UHV.Illustrate herein and utilize ripple mistake
Journey calculates the concordance of the voltage's distribiuting characteristic verifying scale model and master mould, master mould herein and the contracting of scale model
Ratio method is identical with UHV scale model method for designing, and master mould each circle head end time domain voltage distribution waveform is such as
Shown in Fig. 2, scale model each circle head end time domain voltage distribution waveform is as shown in Figure 3.The voltage wave of corresponding circle is found by contrast
Process is essentially identical, and error is less than 5%, is i.e. obtained winding voltage distribution character and the grand master pattern of scale model by analysis of experiments
The voltage's distribiuting characteristic of type is essentially identical.
With directly carry out UHV impulse withstand voltage test to its insulating properties test assessment compared with, the present invention
Use scale model to carry out impulse withstand voltage test, its insulating properties be estimated test, cost can be reduced, shorten the cycle,
And it is obtained in that the voltage's distribiuting characteristic of each winding under the surge voltage normally and under failure condition, can be extra-high voltage converter
Fault diagnosis under transformator surge voltage provides foundation；Owing to scale model volume is little, electric pressure is low, test loop element
Configuration simplifies, and test adjustment is convenient, therefore can also reduce the cost of test, and obtain what master mould test can not obtain
Test data.
Claims (4)
1. a UHV impulse voltage endurance test method based on scale model, it is characterised in that include walking as follows
Rapid:
Step one, according to based on the scale model structure contracted than Design Theory, to inner coil configuration modeling and simulating, obtains contracting ratio
The distributed constant of the electric capacity of model winding, inductance and resistance, loop built by the testing equipment then simulating reality, by adjusting electricity
Potential source capacitance parameter and resistance parameter obtain required test waveform；
Step 2, arranges multiple extraction tap to obtain required test waveform on scale model；
Step 3, requires to make actual main capacitance C according to emulation gained distributed constant and design1, wavefront resistance R1, electric discharge electricity
Resistance R2, sampling resistor R3, connect composition test loop, according to test waveform, capacitance parameter and the resistance parameter of test loop entered
Row sum-equal matrix, finally gives required test waveform；
Step 4, after determining surge voltage source dates, tests under low-voltage-grade, first measures under surge voltage each
Draw the voltage's distribiuting characteristic of tap；Utilize arrange to draw the failure condition that tap simulation is different, obtain typical case by test
Voltage waveform and neutral point current waveform, the winding voltage in the case of analysis and research typical fault on internal winding under failure condition
Distribution character and winding transfer function characteristics, be analyzed with simulation result simultaneously；
Step 5, obtains the winding normal condition under surge voltage by analysis and research and the voltage's distribiuting under failure condition is special
Property, utilize scale-relation to be back-calculated to obtain the voltage's distribiuting characteristic of UHV.
2. UHV impulse voltage endurance test method based on scale model as claimed in claim 1, its feature
It is: main capacitance C1, spark gap G, wavefront resistance R1 and discharge resistance R2 be sequentially connected in series, wavefront resistance R1 and electric discharge electricity
The node of resistance R2 is through resitstance voltage divider ground connection, and the source side winding of UHV scale model is in parallel with discharge resistance R2
Connecting, UHV scale model arranges the extraction tap being connected with the equipment of measurement, and UHV contracts
Resistance R more sampled than the neutral point of model3Ground connection.
3. UHV impulse voltage endurance test method based on scale model as claimed in claim 1, its feature
It is: utilize the tap of drawing of setting to simulate different failure conditions particularly as follows: utilize the extraction tap analogue ground event arranged
Barrier, utilizes and draws the short trouble that the simulation of tap combination of two is different.
4. UHV impulse voltage endurance test method based on scale model as claimed in claim 3, its feature
It is: described short trouble includes turn-to-turn short circuit, all over the ground short circuit.
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