CN207114702U - A kind of Partial Discharge in Power Transformer simulation experiment platform - Google Patents
A kind of Partial Discharge in Power Transformer simulation experiment platform Download PDFInfo
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- CN207114702U CN207114702U CN201720908731.5U CN201720908731U CN207114702U CN 207114702 U CN207114702 U CN 207114702U CN 201720908731 U CN201720908731 U CN 201720908731U CN 207114702 U CN207114702 U CN 207114702U
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Abstract
It the utility model is related to power equipment state monitoring and fault diagnosis technology field, more particularly to a kind of Partial Discharge in Power Transformer simulation experiment platform, the platform include maintenance power source special, isolating transformer, power-supply controller of electric, wave filter, without partial discharge test transformer, analogue transformer body, discharging model, without shelf depreciation coupled capacitor, electric impulse signal detector；The utility model constructs Partial Discharge in Power Transformer analogue test platform in laboratory, real simulation transformer is realized along shelf depreciations such as face shelf depreciations, to verify partial discharge monitoring device or detecting instrument to measurement effect of the transformer along discharge defects such as face shelf depreciations, partial discharge monitoring device or detecting instrument product control quality, the general level of the health and service efficiency are favorably improved, has reached partial discharge monitoring device or risk in detecting instrument O＆M, efficiency and cost synthesis is optimal.
Description
Technical field
It the utility model is related to power equipment state monitoring and fault diagnosis technology field, and in particular to a kind of power transformer
General ability portion Discharge Simulation experiment porch.
Background technology
Shelf depreciation is one of key character parameter for reflecting the apparatus insulated performance of power transformer, and it is power transformer
The reason for sign and the form of expression of apparatus insulated deterioration are apparatus insulated further deterioration again.Therefore, power transformer is simulated
The feature of apparatus local discharge, it can aid in the validity of checking detection method and find that the insulation of its internal early stage lacks early
Fall into, and by timely fault diagnosis and state evaluation, to take specific treatment measures, avoid its malignant development.
The position that shelf depreciation easily occurs inside power transformer mainly has:End lead-out wire and its turn-to-turn, end are exhausted
Bubble in edge cardboard, turn-to-turn insulation, screen, coil pressure plate, iron core, fastener and oil etc..They can be summarized as:With insulation
The oil-gap of barrier discharges, the air gap electric discharge in solid insulation, bubble in oil electric discharge, creeping discharge, floating potential discharge,
The types such as the electric discharge that impurity foot bridge induces.It can be divided into gap discharge, creeping discharge, needle plate electric discharge, ground connection electricity from electrical breakdown angle
Pole is discharged, metallic particles electric discharge.These situations are typically inevitable in transformer device structure.
And as electric power enterprise is increasingly deep in terms of research, application apparatus status monitoring assessment technique, superfrequency, surpass
Detection method for local discharge such as sound etc. are widely used to detect among transformer equipment shelf depreciation.But transformer complexity
Internal structure will cause ultrahigh frequency electromagnetic wave signal in the serious catadioptric of inside transformer, therefore be difficult with superfrequency detection method
Accurately identify the pattern and intensity of inside transformer electric discharge.Therefore it is badly in need of disclosure satisfy that when producing electric discharge and not influence insulating barrier grand
See the discharging model of performance.
In consideration of it, being necessary to develop a kind of Partial Discharge in Power Transformer simplation verification platform, and pass through power transformer
Real shelf depreciation inside shelf depreciation simulation experiment system analogue transformer, realize that record, examination, study of various are locally put
Power utilization monitoring device and detecting instrument for the detection frequency of shelf depreciation, sensitivity, the linearity, step-by-step counting, dynamic range, examine
The technological means of the characteristic parameters such as disconnected identification, improves monitoring device product control quality, the general level of the health and service efficiency.
The content of the invention
In order to solve the above problems, the utility model provides a kind of Partial Discharge in Power Transformer simulation experiment platform,
Concrete technical scheme is as follows：
A kind of Partial Discharge in Power Transformer simulation experiment platform includes maintenance power source special, isolating transformer, power supply control
Device processed, wave filter, without partial discharge test transformer, analogue transformer body, discharging model, without shelf depreciation coupled capacitor,
Electric impulse signal detector；
The maintenance power source special is used to provide power supply, and is boosted or be depressured control；The isolating transformer is used
In making to realize electric insulation between maintenance power source special and power-supply controller of electric, suppress high frequency spurs and transmit to wave filter；The electricity
Source controller is used for electric current, voltage, time and the divide-shut brake monitor, adjust, control input exports, and realizes overcurrent protection；Institute
Wave filter is stated to be used for filtering clutter, suppress interference noise；The no partial discharge test transformer is for miscellaneous in power supply of forgoing
Wave interference, adjust size, the size of output voltage of input voltage；The analogue transformer body is used to coordinate with discharging model
Simulate Partial Discharge in Power Transformer；The discharging model, which is used to simulate, produces shelf depreciation；The no shelf depreciation coupling electricity
Hold for picking up local discharge signal caused by analogue transformer body；The electric impulse signal detector is used to detect electric discharge mould
The pulse signal of shelf depreciation caused by type；
The maintenance power source special is connected with isolating transformer, and isolating transformer is connected with power-supply controller of electric, power supply
Device is connected with wave filter, and wave filter is connected with without partial discharge test transformer, and no partial discharge test transformer becomes with simulation
Depressor body connects, and no shelf depreciation coupled capacitor and discharging model are arranged on analogue transformer body interior, electric impulse signal
Detector is connected with without shelf depreciation coupled capacitor.
Further, the maintenance power source special rated output voltage is 400 volts of three-phase alternating current, and its rated capacity is 18,000
Volt-ampere.
Further, the isolating transformer is three-phase transformer.
Further, the power-supply controller of electric is HT testing transformer power console.
Further, the wave filter is three-phase and four-line formula wave filter.
Further, the no partial discharge test transformer is oil-immersed self-cooled three-phase three-winding transformer.
Further, the size of the no shelf depreciation coupled capacitor is 40~60 pico farads.
Further, the instrument for measuring partial discharge of base when the electric impulse signal detector is based on high frequency elliptical scanning,
Further, the discharging model includes internal clearance partial discharge model, suspension electrode partial discharge model, inside
It is sophisticated partial discharge model, metallic particles partial discharge model, internal along face partial discharge model, turn-to-turn insulation shelf depreciation mould
Type, transformer magnetic screen discharging model, sleeve of main transformer partial discharge model, grounding electrode partial discharge model.
Further, the no partial discharge test transformer is connected with instrument measurement end, and the instrument measurement end is used to connect
Measuring instrumentss are connect to measure the operating voltage of no partial discharge test transformer, operating current.
The utility model constructs Partial Discharge in Power Transformer analogue test platform in laboratory, with reference to power transformer
The internal structures such as device coil insulate and sleeve pipe handling process, design and have made the platform of emulation shelf depreciation, using rising step by step
Platen press applies test voltage to Partial Discharge in Power Transformer simplation verification platform, and gathers, analyzes the base of local discharge signal
Eigen parameter and profile information.The utility model realizes real simulation partial discharge of transformer, to verify shelf depreciation
Monitoring device or detecting instrument are favorably improved partial discharge monitoring to the measurement effect of the discharge defects such as partial discharge of transformer
Device or detecting instrument product control quality, the general level of the health and service efficiency, partial discharge monitoring device or detecting instrument fortune are reached
Risk, efficiency and cost synthesis in dimension is optimal.
Brief description of the drawings
Fig. 1 is structural representation of the present utility model.
Embodiment
In order to be better understood from the utility model, the utility model is made with specific embodiment below in conjunction with the accompanying drawings further
Explanation：
As shown in figure 1, a kind of Partial Discharge in Power Transformer simulation experiment platform includes maintenance power source special, isolation transformation
Device, power-supply controller of electric, wave filter, without partial discharge test transformer, analogue transformer body, discharging model, without shelf depreciation
Coupled capacitor, electric impulse signal detector；
Maintenance power source special is used to provide power supply, and is boosted or be depressured control；Isolating transformer is used to make maintenance
Electric insulation is realized between power source special and power-supply controller of electric, suppresses high frequency spurs and transmits to wave filter；Power-supply controller of electric is used for
Monitoring, regulation, electric current, voltage, time and the divide-shut brake of control input output, and realize overcurrent protection；Wave filter is used to filter out
Clutter, suppress interference noise；Without partial discharge test transformer for the noise jamming in power supply of forgoing, input voltage is adjusted
Size, the size of output voltage；Analogue transformer body is used to coordinate simulation Partial Discharge in Power Transformer with discharging model；Put
Electric model, which is used to simulate, produces shelf depreciation；It is used to pick up without shelf depreciation coupled capacitor local caused by analogue transformer body
Discharge signal；Electric impulse signal detector is used for the pulse signal for detecting shelf depreciation caused by discharging model；And to examine
Tested tester detects the indexs such as the sensitivity of shelf depreciation, the linearity.
Maintenance power source special be connected with isolating transformer, isolating transformer is connected with power-supply controller of electric, power-supply controller of electric and
Wave filter is connected, and wave filter is connected with without partial discharge test transformer, no partial discharge test transformer and analogue transformer
Body connects, and no shelf depreciation coupled capacitor and discharging model are arranged on analogue transformer body interior, electric impulse signal detection
Instrument is connected with without shelf depreciation coupled capacitor.
It is 400 volts of three-phase alternating current to overhaul power source special rated output voltage, and its rated capacity is 18 kilovolt-amperes.Isolation becomes
From the three-phase transformer of SG9-15/0.38 series, it is mainly made up of depressor drum type brake winding and laminated core structure.Power supply control
Device processed selects TPKZT type HT testing transformer power consoles.Wave filter selects Q310 series three phase four-wire type wave filters, its
Rated current is 6 to 50 amperes, and its working frequency is 50 hertz, and its maximum leakage current is less than 2 milliamperes.
It is oil-immersed self-cooled three-phase three-winding transformer without partial discharge test transformer, its rated power is 5 kilovolt-amperes,
Test frequency is 50 hertz of power frequency, and nominal input voltage is 220 volts, and specified maximum output voltage is 160 kilovolts, absolutely
Partial discharge amount is no more than 1 skin storehouse under rated voltage, continuously-running 1 hour under rated voltage UN, i.e., 2/3 rated voltage,
Continuous operation 1 hour under 2/3 rated current, industrial frequency withstand voltage level is 176 kilovolts per minute, and impedance voltage is no more than percent
Ten, output waveform aberration rate is no more than 3 percent.
Rated capacitance size without shelf depreciation coupled capacitor is 50 pico farads, and specified ceiling voltage is 160 kilovolts, percentage
Hundred rated voltages under partial discharge amount be not more than 1 skin storehouse, continuously-running 90 minutes under rated voltage, industrial frequency withstand voltage level is
176 kilovolts per minute, and under 20 degrees Celsius, 0.9 to 1.1 times of rated voltage, dielectric loss angle tangent is not more than 0.002%.
The instrument for measuring partial discharge of base, its testable electric capacity when electric impulse signal detector is based on high frequency elliptical scanning
Scope is 5 to 300 pico farads, and the working method of base is standard-extension-straight line during elliptical scanning, the oval input of high frequency time base
Voltage range is 10 to 275 volts, and the window width of the time window when frequency is 50Hz is 5 to 150 degree, shelf depreciation test pulse
Peak linear indicates and the error of logarithm instruction is not more than 5 percent.
Discharging model includes internal clearance partial discharge model, suspension electrode partial discharge model, inner tip and locally put
It is electric model, metallic particles partial discharge model, internal along face partial discharge model, turn-to-turn insulation partial discharge model, transformer
Magnetic screen discharging model, sleeve of main transformer partial discharge model, grounding electrode partial discharge model.
It is connected without partial discharge test transformer with instrument measurement end, instrument measurement end is used to connect measuring instrumentss to measure
Operating voltage, operating current without partial discharge test transformer, and then grasp the operating voltage of analogue transformer body, work
Situations such as electric current, the maximum output voltage at instrument measurement end is 160 volts, and intrinsic standoff ratio is 1 to 1000, and measurement error is no more than just
Minus 1 percent.
Before test, Partial Discharge in Power Transformer simulation experiment platform provided by the utility model is placed in relative humidity not
More than 80 percent, and ventilation, non-corrosiveness gas, no-sundries laboratory in.During test, connected according to Fig. 1, open inspection
Power source special is repaiied, when reaching shelf depreciation threshold value, discharging model produces significant electric discharge, exhausted so as to the turn-to-turn of analogue transformer
The defects of shelf depreciations such as edge.In checking procedure, decline in initial partial discharge voltage, put in electric impulse signal detector collection of illustrative plates
There is obvious phase range in electric impulse signal distribution, and the change of temperature and pulse maximum amplitude and average pulse is not significantly changed
The overall development trend of amplitude.So the reliable detection lowest amplitude of verified partial discharge monitoring device or detecting instrument can be with
As the basis for estimation for examining its sensitivity, partial discharge monitoring device or detecting instrument detect the pulse letter of different amplitudes respectively
Number can as examine its linear basis for estimation.Moreover, it is judged that when be able to can also be adopted by the way of artificial graphic correlation
Realized with auxiliary software.
Compared with prior art, Partial Discharge in Power Transformer simplation verification platform provided by the utility model, simulation
The shelf depreciation electric discharge phenomena such as inside transformer real turn-to-turn insulation.Specifically refer in the case where stepped-up voltage acts on, discharge mould
Partial discharge pulse's maximum amplitude, average pulse amplitude, pulse power are on the whole with the increase of test voltage caused by type
There is local maximum with voltage rise is applied in increase trend, pulse recurrence frequency.
The above situation meets the primary condition that simulation produces shelf depreciation, possesses examination, research, emulation shelf depreciation
Monitoring device or detecting instrument partial discharge of transformer is detected frequency, sensitivity, the linearity, step-by-step counting, dynamic range and
The technological means of the characteristic parameters such as diagnosis identification, to find partial discharge monitoring device or detecting instrument in engineer applied early
Present in performance issue, and influence accurate measurements, early warning and assess power transformer Abnormal Insulation, improve for electric power
Transformer insulated abnormal monitoring and pre-alerting ability.
The utility model is not limited to above-described embodiment, the foregoing is only of the present utility model preferable
Case study on implementation, not to limit the utility model, all made within spirit of the present utility model and principle are any
Modifications, equivalent substitutions and improvements etc., should be included within the scope of protection of the utility model.
Claims (10)
- A kind of 1. Partial Discharge in Power Transformer simulation experiment platform, it is characterised in that：Including maintenance power source special, isolation transformation Device, power-supply controller of electric, wave filter, without partial discharge test transformer, analogue transformer body, discharging model, without shelf depreciation Coupled capacitor, electric impulse signal detector；The maintenance power source special is used to provide power supply, and is boosted or be depressured control；The isolating transformer is used to make Electric insulation is realized between maintenance power source special and power-supply controller of electric, suppresses high frequency spurs and transmits to wave filter；The power supply control Device processed is used for electric current, voltage, time and the divide-shut brake monitor, adjust, control input exports, and realizes overcurrent protection；The filter Ripple device is used for filtering clutter, suppresses interference noise；The no partial discharge test transformer is done for the clutter in power supply of forgoing Disturb, adjust size, the size of output voltage of input voltage；The analogue transformer body, which is used to coordinate with discharging model, simulates Partial Discharge in Power Transformer；The discharging model, which is used to simulate, produces shelf depreciation；The no shelf depreciation coupled capacitor is used In local discharge signal caused by pickup analogue transformer body；The electric impulse signal detector is used to detect discharging model production The pulse signal of raw shelf depreciation；It is described maintenance power source special be connected with isolating transformer, isolating transformer is connected with power-supply controller of electric, power-supply controller of electric and Wave filter is connected, and wave filter is connected with without partial discharge test transformer, no partial discharge test transformer and analogue transformer Body connects, and no shelf depreciation coupled capacitor and discharging model are arranged on analogue transformer body interior, electric impulse signal detection Instrument is connected with without shelf depreciation coupled capacitor.
- A kind of 2. Partial Discharge in Power Transformer simulation experiment platform according to claim 1, it is characterised in that：The inspection It is 400 volts of three-phase alternating current to repair power source special rated output voltage, and its rated capacity is 18 kilovolt-amperes.
- A kind of 3. Partial Discharge in Power Transformer simulation experiment platform according to claim 1, it is characterised in that：It is described every It is three-phase transformer from transformer.
- A kind of 4. Partial Discharge in Power Transformer simulation experiment platform according to claim 1, it is characterised in that：The electricity Source controller is HT testing transformer power console.
- A kind of 5. Partial Discharge in Power Transformer simulation experiment platform according to claim 1, it is characterised in that：The filter Ripple device is three-phase and four-line formula wave filter.
- A kind of 6. Partial Discharge in Power Transformer simulation experiment platform according to claim 1, it is characterised in that：The nothing Partial discharge test transformer is oil-immersed self-cooled three-phase three-winding transformer.
- A kind of 7. Partial Discharge in Power Transformer simulation experiment platform according to claim 1, it is characterised in that：The nothing The size of shelf depreciation coupled capacitor is 40~60 pico farads.
- A kind of 8. Partial Discharge in Power Transformer simulation experiment platform according to claim 1, it is characterised in that：The electricity The instrument for measuring partial discharge of base when pulse signal detection instrument is based on high frequency elliptical scanning.
- A kind of 9. Partial Discharge in Power Transformer simulation experiment platform according to claim 1, it is characterised in that：It is described to put Electric model includes internal clearance partial discharge model, suspension electrode partial discharge model, inner tip partial discharge model, metal Granule partial discharging model, internal discharged mould along face partial discharge model, turn-to-turn insulation partial discharge model, transformer magnetic screen Type, sleeve of main transformer partial discharge model, grounding electrode partial discharge model.
- A kind of 10. Partial Discharge in Power Transformer simulation experiment platform according to claim 1, it is characterised in that：It is described It is connected without partial discharge test transformer with instrument measurement end, the instrument measurement end is used to connect measuring instrumentss to measure no office The operating voltage of portion's discharge test transformer, operating current.
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109444690A (en) * | 2018-11-21 | 2019-03-08 | 贵州电网有限责任公司 | A kind of test method of analogue transformer built-in electrical insulation defect electric discharge |
| CN110361637A (en) * | 2019-07-22 | 2019-10-22 | 西南交通大学 | A kind of simulation experiment platform and method for studying cable terminal discharge Acoustic Emission Characteristic |
| CN111289856A (en) * | 2020-03-08 | 2020-06-16 | 国网山西省电力公司电力科学研究院 | Distribution network switch cabinet partial discharge detection device/method based on electric pulse technology |
| CN111458612A (en) * | 2020-05-29 | 2020-07-28 | 国网陕西省电力公司电力科学研究院 | State monitoring and defect simulation system for electrical insulation performance of oil-immersed sleeve |
| CN111650485A (en) * | 2020-06-16 | 2020-09-11 | 苏州华安普新能源科技有限公司 | Online intermittent monitoring method, medium, sensor and analysis station for power transmission and transformation equipment |
| CN115308543A (en) * | 2022-08-03 | 2022-11-08 | 重庆大学 | Method for determining waveform parameter range with maximum influence on air insulation fault risk rate |
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2017
- 2017-07-25 CN CN201720908731.5U patent/CN207114702U/en active Active
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109444690A (en) * | 2018-11-21 | 2019-03-08 | 贵州电网有限责任公司 | A kind of test method of analogue transformer built-in electrical insulation defect electric discharge |
| CN109444690B (en) * | 2018-11-21 | 2020-12-08 | 贵州电网有限责任公司 | Test method for simulating internal insulation defect discharge of transformer |
| CN110361637A (en) * | 2019-07-22 | 2019-10-22 | 西南交通大学 | A kind of simulation experiment platform and method for studying cable terminal discharge Acoustic Emission Characteristic |
| CN111289856A (en) * | 2020-03-08 | 2020-06-16 | 国网山西省电力公司电力科学研究院 | Distribution network switch cabinet partial discharge detection device/method based on electric pulse technology |
| CN111458612A (en) * | 2020-05-29 | 2020-07-28 | 国网陕西省电力公司电力科学研究院 | State monitoring and defect simulation system for electrical insulation performance of oil-immersed sleeve |
| CN111650485A (en) * | 2020-06-16 | 2020-09-11 | 苏州华安普新能源科技有限公司 | Online intermittent monitoring method, medium, sensor and analysis station for power transmission and transformation equipment |
| CN115308543A (en) * | 2022-08-03 | 2022-11-08 | 重庆大学 | Method for determining waveform parameter range with maximum influence on air insulation fault risk rate |
| CN115308543B (en) * | 2022-08-03 | 2023-12-22 | 重庆大学 | Method for determining waveform parameter range with maximum influence on air insulation fault risk rate |
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