CN104034255B - The winding deformation of power transformer online test method injected based on pulse-couple - Google Patents
The winding deformation of power transformer online test method injected based on pulse-couple Download PDFInfo
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- CN104034255B CN104034255B CN201410315224.1A CN201410315224A CN104034255B CN 104034255 B CN104034255 B CN 104034255B CN 201410315224 A CN201410315224 A CN 201410315224A CN 104034255 B CN104034255 B CN 104034255B
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Abstract
The invention discloses a kind of winding deformation of power transformer online test method injected based on pulse-couple, belong to power equipment online measuring technique field.This method comprises the following steps：1) high-voltage nanosecond squarer generation high-voltage nanosecond pulse signal；2) high-voltage nanosecond pulse signal injects and protection circuit by signal, transmits to the transformer signal transducer for being installed on bushing shell for transformer, by Nanosecond pulse signal coupled on winding；3) current responsing signal of data collecting module collected high-voltage nanosecond pulse signal and winding ends neutral point, and be converted into data signal；4) data processing module carries out Fourier transformation to described data signal, asks for the frequency response curve of winding, and calculates the characteristic parameters such as the coefficient correlation of the frequency response curve, standard deviation, differentiates the deformation extent of Transformer Winding.This method can realize the non-intrusion type on-line checking of winding deformation, and have the advantages that detection speed it is fast, to power system without undermining low cost.
Description
Technical field
The invention belongs to power equipment online measuring technique field, it is related to a kind of power transformer injected based on pulse-couple
Device winding deformation online test method.
Background technology
Power transformer is as the equipment of transformer station's core the most, and its safe and stable operation is to ensuring power supply reliability and carrying
High economy plays an important roll.According to incompletely statistics, cause in transformer damage and the various failure factors stopped transport, winding becomes
Shape occupies nearly half of the country.The transport of transformer, operation, impaired insulation ag(e)ing, the blast of oil dissolved gas and earthquake etc.
Force majeure can cause the deformation of winding in various degree, in particularly running in the case of the externally ported short circuit of transformer, around
Group short circuit currents form huge electromagnetic force so that winding produces slight deformation failure.With the development of deformation extent, winding
Insulation is impaired, further the anti-short circuit capability of reduction winding, and finally under the effect of less short circuit current flow, transformer also can
Damaged because of the expendable deformation of winding, cause the stoppage in transit of power network.
At present, scholar is just actively pushing forward the development of deformation of transformer winding detection field research work all over the world.Successively
The methods such as short circuit impedance method, Low Voltage Impulse Method, frequency response method, vibratory drilling method and supercritical ultrasonics technology are invented.Wherein, frequency response method
It is considered as mode economic, effective, reproducible, that sensitivity is high, is widely used in the test event of power system, simultaneously
This method has also been put into professional standard.However, this mode needs transformer out of service, it is impossible in transformer normal work
Shi Youxiao obtains the state of winding change in time, it is impossible to online tracking and the deformation failure for finding winding, it is more likely that cause
The catastrophic discontinuityfailure of transformer.Therefore, if on-line monitoring and the detection of winding deformation of power transformer failure can be carried out, in time
Obtain the situation of winding, the Hidden fault of early warning winding, the maintenance of planned arrangement transformer, thus it is ensured that power system
Safe and stable operation, improves the reliability of power supply, economic benefit is lifted, with very important Practical significance.
In existing deformation of transformer winding detection method, use frequency response method more, mainly comprise the following steps：Generation is swept
Frequency signal, is loaded onto on winding；Data acquisition circuit collection voltages signal；Data processing module is carried out to the data signal of collection
Frequency response is converted, and calculates winding deformation differentiation coefficient correlation, and detection deformation of transformer winding degree can be achieved.However, should
Method is only capable of using offline, it is impossible to which the online deformation to Winding in Power Transformer is detected, it is impossible to obtain winding deformation in time
Information, thus be difficult to resist catastrophic discontinuityfailure.
The content of the invention
In view of this, it is an object of the invention to provide a kind of winding deformation of power transformer injected based on pulse-couple
Online test method, this method has non-intrusion type, detection speed fast, lossless to power system and can realize on-line checking etc.
Advantage.
To reach above-mentioned purpose, the present invention provides following technical scheme：
A kind of winding deformation of power transformer online test method injected based on pulse-couple, is comprised the following steps：Step
Rapid one：High-voltage nanosecond squarer generates high-voltage nanosecond pulse signal；Step 2：High-voltage nanosecond pulse signal is by letter
Number injection and protection circuit, transmit to the transformer signal transducer for being installed on bushing shell for transformer, Nanosecond pulse signal coupled
To winding；Step 3：The current-responsive letter of data collecting module collected high-voltage nanosecond pulse signal and winding ends neutral point
Number, and it is converted into data signal；Step 4：Data processing module carries out Fourier transformation to described data signal, ask for around
The frequency response curve of group, and the characteristic parameters such as the coefficient correlation of the frequency response curve, standard deviation are calculated, differentiate transformation
The deformation extent of device winding.
Further, in step one, communicated by host computer with central control module, generation high pressure needed for host computer is provided
The parameter instruction of nanosecond pulse, central control module produces corresponding drive signal, and driving pulse occurs circuit and produces high pressure
Nanosecond pulse；
The central control module includes single machine unit, field programmable gate array unit, regulating circuit unit and same
Walk triggers circuit unit；The single machine unit, for generating triggering control parameter, gives birth to by field programmable gate array unit
Into control parameter and trigger parameter, voltage conditioned signal and synchronization are generated respectively through regulating circuit unit and synchronous trigger element
Trigger signal, is transmitted to pulse generating circuit；
The pulse generating circuit is mainly made up of Marx generator, including high-voltage DC power supply, diode, charging electricity
Hold, mos field effect transistor is switched, wherein high-voltage DC power supply is carried out by described voltage conditioned signal
Intelligent control, mos field effect transistor switch carries out switch conduction with closing by described synchronous triggering signal
Disconnected intelligent control.
Further, in step 2, signal injection and protection circuit by matched with coaxial hyperfrequency cable build-out resistor,
Filter capacitor, gas-discharge tube and piezo-resistance are constituted, and transformer signal transducer is installed on the transformer close to ground connection flange
On sleeve pipe external insulation layer；
Signal injects and protection circuit forward direction realizes that Nanosecond pulse signal is lossless and is injected into transformer signal transducer, simultaneously
Filter action reversely is played for the sleeve pipe guide rod power frequency high voltage that transformer signal transducer is coupled, high-pass filter is served
Effect, protects high-voltage nanosecond squarer not influenceed and damaged by power frequency high voltage；
Transformer signal transducer is wound around the metal sheet band on transformer high-voltage bushing external insulation layer, and configuration connects
Mouthful, described metal sheet band and guide rod inside bushing shell for transformer and sleeve pipe medium formation coupled capacitor, based on the coupled capacitor
It can realize that the manifold type of Nanosecond pulse signal is injected into the head end of winding.
Further, in step 3, data acquisition module mainly by analog-digital converter, voltage sensor, current sensor,
High-pass filter is constituted, and is changed described high-voltage nanosecond pulse signal to threshold voltage by a narrow margin by voltage sensor, is turned by modulus
Parallel operation carries out data acquisition to low voltage signal；Current sensor carries out I-V turns to winding ends neutral point current signal simultaneously
Change, and pass through high-pass filter, high frequency response signal is gathered while filtering out power frequency current signal, and by analog-digital converter to low
Voltage signal carries out data acquisition, transmits to data processing module.
Further, in step 4, data processing module includes frequency response curve drafting module, characteristic parameter and calculates mould
Block and winding state judge module；The frequency response curve drafting module, the data signal of data collecting module collected is entered
Row Fourier transformation, the calculating of frequency response data is carried out according to following formula, so as to draw frequency response curve：
In formula, Iout(f) it is the current responsing signal of winding ends neutral point, Vin(f) it is high-voltage nanosecond pulse signal；
Characteristic parameter computing module, calculates according to frequency response data and obtains coefficient correlation, standard deviation, extreme point correspondence
The characteristic parameters such as situation；Winding state judge module the criterion of characteristic parameter and winding deformation is contrasted so that judge around
The degree of group deformation, obtains the state of winding, realizes the on-line checking of winding deformation.
The beneficial effects of the present invention are：1st, the present invention uses transformer signal transducer, so as to truly realize
The non-intrusion type on-line checking of winding deformation.The sensor bulk is small, light weight, does not change the original wiring of power system,
It is safer.2nd, the present invention, because its frequency band is higher, avoids power frequency and part using high-voltage nanosecond pulse signal excitation winding
Interference signal, improves the ability of electromagnetism interference.3rd, the present invention uses high-voltage nanosecond pulse signal, because it includes what is enriched
Spectrum component, can realize quick detection in the case where only inputting several pulses, improve the speed and efficiency of detection.4th, originally
Invention uses high-voltage nanosecond pulse signal, because its generation circuit is simply various, enormously simplify the device volume needed for method
And quantity, while reducing cost.5th, the present invention carries out the assessment of winding deformation state according to frequency-response characteristic parameter, more
Intuitively.
Brief description of the drawings
In order that the purpose of the present invention, technical scheme and beneficial effect are clearer, the present invention provides drawings described below and carried out
Explanation：
Fig. 1 is the flow chart of the method for the invention；
Fig. 2 is transformer signal transducer installation site figure of the invention；
Fig. 3 is the realization figure of the method for the invention；
Fig. 4 is the on high-tension side frequency of 110kV/10.5kV three-phase transformers that the method for the invention applies to after an overhaul
Rate response curve.
Embodiment
Below in conjunction with accompanying drawing, the preferred embodiments of the present invention are described in detail.
Fig. 1 is the flow chart of the method for the invention, and the method for the invention comprises the following steps：Step one：High pressure is received
Second square-wave pulse generator generation high-voltage nanosecond pulse signal；Step 2：High-voltage nanosecond pulse signal injects and protected by signal
Protection circuit, is transmitted to the transformer signal transducer for being installed on bushing shell for transformer, by Nanosecond pulse signal coupled on winding；Step
Rapid three：The current responsing signal of data collecting module collected high-voltage nanosecond pulse signal and winding ends neutral point, and be converted into
Data signal；Step 4：Data processing module carries out Fourier transformation to described data signal, asks for the frequency response of winding
Curve, and the characteristic parameters such as the coefficient correlation of the frequency response curve, standard deviation are calculated, differentiate the deformation of Transformer Winding
Degree.
Wherein, in step one, communicated by host computer with central control module, generation high pressure is received needed for host computer is provided
The parameter instruction of pulse per second (PPS), central control module produces corresponding drive signal, and driving pulse occurs circuit generation high pressure and received
Pulse per second (PPS)；
The central control module includes single machine unit, field programmable gate array unit, regulating circuit unit and same
Walk triggers circuit unit；The single machine unit, for generating triggering control parameter, gives birth to by field programmable gate array unit
Into control parameter and trigger parameter, voltage conditioned signal and synchronization are generated respectively through regulating circuit unit and synchronous trigger element
Trigger signal, is transmitted to pulse generating circuit；
The pulse generating circuit is mainly made up of Marx generator, including high-voltage DC power supply, diode, charging electricity
Hold, mos field effect transistor is switched, wherein high-voltage DC power supply is carried out by described voltage conditioned signal
Intelligent control, mos field effect transistor switch carries out switch conduction with closing by described synchronous triggering signal
Disconnected intelligent control.
In step 2, signal injection and protection circuit are by the build-out resistor, the filtered electrical that are matched with coaxial hyperfrequency cable
Hold, gas-discharge tube and piezo-resistance are constituted, transformer signal transducer is installed on outside the bushing shell for transformer of ground connection flange
On insulating barrier；
Signal injects and protection circuit forward direction realizes that Nanosecond pulse signal is lossless and is injected into transformer signal transducer, simultaneously
Filter action reversely is played for the sleeve pipe guide rod power frequency high voltage that transformer signal transducer is coupled, high-pass filter is served
Effect, protects high-voltage nanosecond squarer not influenceed and damaged by power frequency high voltage；
Transformer signal transducer is wound around the metal sheet band on transformer high-voltage bushing external insulation layer, and configuration connects
Mouthful, described metal sheet band and guide rod inside bushing shell for transformer and sleeve pipe medium formation coupled capacitor, based on the coupled capacitor
It can realize that the manifold type of Nanosecond pulse signal is injected into the head end of winding.
In step 3, data acquisition module is mainly filtered by analog-digital converter, voltage sensor, current sensor, high pass
Ripple device is constituted, and is changed described high-voltage nanosecond pulse signal to threshold voltage by a narrow margin, by analog-digital converter pair by voltage sensor
Low voltage signal carries out data acquisition；Current sensor carries out I-V conversions to winding ends neutral point current signal simultaneously, and passes through
High-pass filter is crossed, high frequency response signal is gathered while filtering out power frequency current signal, and low-voltage is believed by analog-digital converter
Number carry out data acquisition, transmit to data processing module.
In step 4, data processing module include frequency response curve drafting module, characteristic parameter computing module and around
Group state-evaluation module；The frequency response curve drafting module, the data signal of data collecting module collected is carried out in Fu
Leaf transformation, the calculating of frequency response data is carried out according to following formula, so as to draw frequency response curve：
In formula, Iout(f) it is the current responsing signal of winding ends neutral point, Vin(f) it is high-voltage nanosecond pulse signal；
Characteristic parameter computing module, calculates according to frequency response data and obtains coefficient correlation, standard deviation, extreme point correspondence
The characteristic parameters such as situation；Winding state judge module the criterion of characteristic parameter and winding deformation is contrasted so that judge around
The degree of group deformation, obtains the state of winding, realizes the on-line checking of winding deformation.
Fig. 4 is the on high-tension side frequency of 110kV/10.5kV three-phase transformers that the method for the invention applies to after an overhaul
Rate response curve.
Finally illustrate, preferred embodiment above is merely illustrative of the technical solution of the present invention and unrestricted, although logical
Cross above preferred embodiment the present invention is described in detail, it is to be understood by those skilled in the art that can be
Various changes are made to it in form and in details, without departing from claims of the present invention limited range.
Claims (3)
1. a kind of winding deformation of power transformer online test method injected based on pulse-couple, it is characterised in that：Including with
Lower step：
Step one：High-voltage nanosecond squarer generates high-voltage nanosecond pulse signal；Step 2：High-voltage nanosecond pulse signal
By signal injection and protection circuit, transmit to the transformer signal transducer for being installed on bushing shell for transformer, nanosecond pulse is believed
Number coupled on winding；
Step 3：The current responsing signal of data collecting module collected high-voltage nanosecond pulse signal and winding ends neutral point, and
It is converted into data signal；
Step 4：Data processing module carries out Fourier transformation to described data signal, asks for the frequency response curve of winding,
And the coefficient correlation of the frequency response curve, standard deviation are calculated as characteristic parameter, differentiate the deformation journey of Transformer Winding
Degree；
In step one, communicated by host computer with central control module, generation high-voltage nanosecond pulse needed for host computer is provided
Parameter instruction, central control module produces corresponding drive signal, and driving pulse occurs circuit and produces high-voltage nanosecond pulse；
The central control module includes single machine unit, field programmable gate array unit, regulating circuit unit and synchronously touched
Power Generation Road unit；The single machine unit, for generating triggering control parameter, generates by field programmable gate array unit and controls
Parameter and trigger parameter processed, generate voltage conditioned signal respectively through regulating circuit unit and synchronous trigger element and synchronously trigger
Signal, is transmitted to pulse generating circuit；
The pulse generating circuit is mainly made up of Marx generator, including high-voltage DC power supply, diode, charging capacitor,
Mos field effect transistor is switched, and wherein high-voltage DC power supply carries out intelligence by described voltage conditioned signal
Control, mos field effect transistor switch carries out switch conduction and shut-off by described synchronous triggering signal
Intelligent control；
In step 2, signal injection and protection circuit are by the build-out resistor matched with coaxial hyperfrequency cable, filter capacitor, gas
Body discharge tube and piezo-resistance are constituted, and transformer signal transducer is installed on the bushing shell for transformer external insulation layer close to ground connection flange
On；Signal injects and protection circuit forward direction realizes that Nanosecond pulse signal is lossless and is injected into transformer signal transducer, while reversely
Filter action is played for the sleeve pipe guide rod power frequency high voltage that transformer signal transducer is coupled, the work of high-pass filter is served
With protecting high-voltage nanosecond squarer not influenceed and damaged by power frequency high voltage；
Transformer signal transducer is wound around the metal sheet band on transformer high-voltage bushing external insulation layer, and configures interface, institute
The metal sheet band stated and guide rod inside bushing shell for transformer and sleeve pipe medium formation coupled capacitor, can be real based on the coupled capacitor
The manifold type of existing Nanosecond pulse signal is injected into the head end of winding.
2. a kind of winding deformation of power transformer on-line checking side injected based on pulse-couple according to claim 1
Method, it is characterised in that：In step 3, data acquisition module mainly by analog-digital converter, voltage sensor, current sensor,
High-pass filter is constituted, and is changed described high-voltage nanosecond pulse signal to threshold voltage by a narrow margin by voltage sensor, is turned by modulus
Parallel operation carries out data acquisition to low voltage signal；Current sensor carries out I-V turns to winding ends neutral point current signal simultaneously
Change, and pass through high-pass filter, high frequency response signal is gathered while filtering out power frequency current signal, and by analog-digital converter to low
Voltage signal carries out data acquisition, transmits to data processing module.
3. a kind of winding deformation of power transformer on-line checking side injected based on pulse-couple according to claim 1
Method, it is characterised in that：In step 4, data processing module includes frequency response curve drafting module, characteristic parameter and calculates mould
Block and winding state judge module；The frequency response curve drafting module, the data signal of data collecting module collected is entered
Row Fourier transformation, the calculating of frequency response data is carried out according to following formula, so as to draw frequency response curve：
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In formula, Iout(f) it is the current responsing signal of winding ends neutral point, Vin(f) it is high-voltage nanosecond pulse signal；Feature is joined
Computing module is measured, obtain coefficient correlation, standard deviation, extreme point correspondence situation according to frequency response data calculating joins as feature
Amount；Winding state judges module and is contrasted the criterion of characteristic parameter and winding deformation, so that judge the degree of winding deformation,
The state of winding is obtained, the on-line checking of winding deformation is realized.
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| CN104833841B (en) * | 2015-05-06 | 2018-01-09 | 国家电网公司 | A kind of transformer station invades Zenith tracking method |
| CN106240948B (en) * | 2016-08-08 | 2018-09-14 | 龙岩烟草工业有限责任公司 | Deformation cigarette packet inspection method, device and system |
| CN106526409B (en) * | 2016-10-28 | 2019-03-15 | 华北电力大学（保定） | A kind of deformation of transformer winding live testing system and its test method |
| CN107390081A (en) * | 2017-08-07 | 2017-11-24 | 华北电力大学 | It is a kind of to be used for the device and method being monitored powered to deformation of transformer winding |
| CN107478949A (en) * | 2017-08-07 | 2017-12-15 | 中国电力科学研究院 | A kind of deformation of transformer winding inline diagnosis method and system |
| CN108872856B (en) | 2018-07-16 | 2019-04-09 | 山东固特电气有限公司 | Generator amature winding state detection device and method |
| CN109191448B (en) * | 2018-09-03 | 2021-11-02 | 重庆大学 | Transformer fault identification method based on three-dimensional coordinate drawing and digital image processing |
| CN109525212A (en) * | 2018-12-29 | 2019-03-26 | 西安交通大学 | A kind of intelligent scanning signal processing unit and working method |
| CN110763932A (en) * | 2019-10-14 | 2020-02-07 | 国网江苏省电力有限公司盐城供电分公司 | Transformer fault detection system based on non-contact injection excitation signal and detection method thereof |
| CN110824389A (en) * | 2019-11-19 | 2020-02-21 | 西南大学 | IFRA-based synchronous generator winding short-circuit fault detection method |
| CN113189515A (en) * | 2021-02-09 | 2021-07-30 | 重庆大学 | IFRA magnetic coupling-based reactor turn-to-turn short circuit fault non-contact type online detection method |
| CN113985166A (en) * | 2021-10-19 | 2022-01-28 | 国网重庆市电力公司电力科学研究院 | Sleeve and transformer winding state monitoring device based on pulse frequency response method |
| CN114396866A (en) * | 2021-12-30 | 2022-04-26 | 广东电网有限责任公司 | Transformer winding deformation fault detection method and device |
| CN114859271A (en) * | 2022-04-18 | 2022-08-05 | 云南电网有限责任公司电力科学研究院 | Method, apparatus and system for diagnosing winding state of transformer, apparatus and medium |
| CN117706300B (en) * | 2023-12-13 | 2024-07-12 | 西南交通大学 | Transformer partial discharge state detection method based on pulse coupling injection |
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| US6549017B2 (en) * | 2000-05-04 | 2003-04-15 | Georgia Tech Research Corporation | System and method for on-line impulse frequency response analysis |
| WO2009069145A2 (en) * | 2007-09-27 | 2009-06-04 | Indian Institute Of Technology, Bombay | A diagnostic method for determining deformations in a transformer winding |
| CN101556299B (en) * | 2009-05-18 | 2011-11-30 | 重庆电力科学试验研究院 | Method for detecting micro deformation of transformer winding |
| CN101937047A (en) * | 2009-06-30 | 2011-01-05 | 上海市电力公司 | Method of utilizing vibration waveform for detecting state of transformer winding |
| CN101701995B (en) * | 2009-11-12 | 2011-11-16 | 重庆大学 | Impulse response analytical test apparatus and method for detecting deformation of transformer winding |
| CN101745178B (en) * | 2009-12-17 | 2013-01-02 | 重庆大学 | Portable high-voltage nanosecond squarer |
| CN101820270B (en) * | 2010-02-05 | 2012-05-02 | 重庆大学 | High pressure picosecond pulse generator |
| CN103743993B (en) * | 2013-10-16 | 2016-04-27 | 西安交通大学 | A kind of method detecting deformation of transformer winding |
| CN103712551A (en) * | 2013-12-04 | 2014-04-09 | 国家电网公司 | Power distribution network transformer low-voltage winding deformation on-line monitoring device and method |
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