CN2864705Y - Device for detecting transformer winding state utilizing sweep frequency power source exciting - Google Patents
Device for detecting transformer winding state utilizing sweep frequency power source exciting Download PDFInfo
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- CN2864705Y CN2864705Y CN 200520047055 CN200520047055U CN2864705Y CN 2864705 Y CN2864705 Y CN 2864705Y CN 200520047055 CN200520047055 CN 200520047055 CN 200520047055 U CN200520047055 U CN 200520047055U CN 2864705 Y CN2864705 Y CN 2864705Y
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Abstract
A device using the excitation of sweep frequency power source to check the winding state of transformer, comprises a corn control module, an exciting module and a data collecting controlling module, wherein, the data collecting controlling module comprises connected vibration sensor, charge amplifier, and data collector, the exciting module comprises connected variable-frequency constant-current source and exciting transformer. The utility model analyzes the change of inherent resonance frequency curvature of the winding of transformer to check the condition of winding, with high sensitivity.
Description
Technical field
The utility model relates to a kind of device that utilizes sweep frequency power source excitation to detect transformer winding state.
Background technology
Transformer is the visual plant in the electric system, and the stability of its operation to the power system security influence greatly.Along with the increase day by day of China's net capacity, capacity of short circuit also constantly increases thereupon, and the huge electromagnetic force that the dash current that forms owing to transformer outlet short circuit produces has constituted serious threat to the physical strength and the dynamic stability of Transformer Winding.At present the running environment of substation equipment and circuit allows of no optimist all the time, because of the distortion that external short circuit causes Transformer Winding to be hit to cause, is common faults comparatively in the transformer operational process, and its safe operation to system has caused very big threat.
During transformer generation suddenly-applied short circuit fault, flow through very big short-circuit current in Transformer Winding, this short-circuit current produces very big electric power on winding under the effect of stray field.Although this transient state duration is very short, transformer still might be damaged.
After transformer suffers sudden short circuit, loosening or slight deformation may at first take place in its winding, analyze deformation of transformer winding by a large amount of experimental studies and have cumulative effect, if can not in time find and repair for loosening and distortion, the anti-short circuit capability that can make transformer so after the loosening and distortion of transformer is being accumulated to a certain degree declines to a great extent and is suffering also can cause under the less dash current big accident and take place.
Except transformer when being subjected to impacting short-circuit current, can take place loosening and distortion, this also can occur the complicated mechanical vibration during in operation at transformer under the long term of the magnetostriction of iron core and running current, these factors combine also can make winding that gradual distortion, loose unstable phenomenon take place, thereby causes the anti-short circuit capability decline of transformer and make transformer have potential accident potential.
Therefore, in operational process after transformer has experienced the external short circuit accident or in the routine maintenance of operation after a period of time, whether how to detect Transformer Winding effectively exists loosening and distortion, thereby judge whether transformer needs maintenance to handle and seem very important, be an important means that ensures the transformer safe operation, so the detection of deformation of transformer winding is one of present transformer conventional test project.
What the detection method to transformer winding state of practical application at present was the most frequently used mainly contains following 2 kinds:
1, short circuit impedance method:
The transformer short-circuit impedance is the equiva lent impedance of transformer inside when loaded impedance is zero, short-circuit impedance be the leakage reactance of Transformer Winding and resistance vector and, because DC Resistance of Transformer is very little with respect to leakage reactance numerical value, so the reflection of the short-circuit impedance of transformer mainly is the leakage reactance of Transformer Winding.By the theoretical analysis of transformer as can be known, transformer leakage reactance value is that the physical dimension by winding is determined, in other words conj.or perhaps by the structures shape of winding, in case Transformer Winding deforms, the leakage reactance of transformer is corresponding in theory also can change, and therefore can reflect indirectly by the detection to the transformer short-circuit impedance whether Transformer Winding inside distortion has taken place.
Generally speaking, after operating transformer has been subjected to the impact of short-circuit current, or when routine inspection regularly, the short-circuit impedance value that records and original record to be compared and judge whether winding distortion has taken place, if the short-circuit impedance value changes greatly, for example be set at variation in the GB and surpass 3%, can confirm that then winding has remarkable distortion.
Fig. 1 is the instrumentation plan of short circuit impedance method, and with the step down side short circuit, the high-pressure side applies trial voltage by pressure regulator, measures corresponding short-circuit voltage U and short-circuit current I, and the short-circuit impedance of transformer is calculated by Z=U/I.
Stipulate according to related standards, transformer is in the short-circuit impedance testing experiment, require to measure the short-circuit impedance of each phase, and measured short-circuit impedance value in test back and test for data in the past compared, according to the degree of its variation, as judging one of important evidence that tested Transformer Winding is whether qualified.
From practical situations, short circuit impedance method has been set up standard in the long-term production practice, and criterion is comparatively clear and definite, has all clearly provided the criterion of winding deformation degree in IEC60076-5 and GB1095-85.But the sensitivity of this method is very low under a lot of situations, and the recall rate of fault is lower, only can obtain clearer and more definite reflection when coil bulk deformation situation is comparatively serious.
2, frequency response method (FRA method, Frequency Response Analysis):
The ultimate principle of frequency response method is that Transformer Winding is considered as a distributed parameter network, it constitutes a passive linear two-port network by distribution parameters such as ground capacitance C, vertical electric capacity K, inductance L, and the characteristic of this network can be described with transfer function H (j ω) on frequency domain.
After the distortion of winding generation local mechanical, corresponding variation can take place in distribution parameters such as its inner inductance L, vertical electric capacity K and ground capacitance C, thereby obtains reflection on the transfer function H (j ω) of network.Whether the network electrical quantity that the situation of change of therefore analyzing the network transfer function curve of Transformer Winding just can be analyzed inside changes, thereby infer whether corresponding physical construction distortion has taken place, this is the foundation and the basis of frequency response method test deformation of transformer winding, as shown in Figure 2, be the equivalent two-port network of Transformer Winding.
The test of frequency response method is at first with a stable sine sweep voltage signal
Be applied to an end of tested Transformer Winding, write down this port then simultaneously
With the voltage on other output port
Thereby the one group of Frequency Response that obtains this tested winding is promptly:
The measurement sensitivity of frequency response method is than the short circuit impedance method height, but because the complicacy of its frequency response waveform, and the differentiation of winding situation is needed more experience, and therefore difficult definite quantitative criterion that forms does not form discrimination standard so far.
Above-mentioned two kinds of methods are that to differentiate the Transformer Winding situation at present the most frequently used, two kinds of methods all are to adopt electric measuring method, starting point all is based on distribution parameter corresponding in the situation drag that obviously distortion takes place Transformer Winding or leakage reactance and changes and measure differentiation, it is comparatively suitable that this to Transformer Winding the situation of more significantly being out of shape takes place, but to winding generation slight deformation, especially the loosening relatively state that Transformer Winding is existed can not provide clearer and more definite judgement, this is because take place under the loosening situation in Transformer Winding, its deformation extent is very little, be reflected in almost not variation of its electrical quantity in the equivalent-circuit model, the variation of its transport function is also just very little.Yet Transformer Winding is loosening its anti-short circuit capability is had very big influence, the situation of therefore studying winding need have the higher method of sensitivity to differentiate.
The utility model content
A kind of device that utilizes sweep frequency power source excitation to detect transformer winding state that the utility model provides, utilize a kind of more sensitive and effective method of testing to detect the mechanical kinetics state of Transformer Winding, can detect the loosening and distortion of Transformer Winding delicately.
In order to achieve the above object, the utility model provides a kind of device that utilizes sweep frequency power source excitation to detect transformer winding state, and it comprises kernel control module, exciting module and data acquisition and control module;
Described exciting module comprises frequency-conversion constant-current source and the exciting transformer that connects by circuit;
Described data acquisition and control module comprises vibration transducer, charge amplifier, the data acquisition unit of circuit connection successively;
Described frequency-conversion constant-current source connects described kernel control module by circuit, and it is applied to the high-pressure side of detected transformer by exciting transformer with the electric current swept frequency excitation signal of exporting, and simultaneously tested Transformer Winding is exported this swept frequency excitation signal;
The amplitude size of the electric current swept frequency excitation signal of this frequency-conversion constant-current source output, the swept frequency range of output frequency and sweep velocity are adjusted by described kernel control module control;
Described exciting transformer is done impedance matching;
Described vibration transducer is arranged on the housing of transformer, and it measures the vibration response signal of tested Transformer Winding under different excited frequencies, and the signal that records is transferred to charge amplifier;
Described charge amplifier amplifies vibration response signal, and the vibration response signal after will amplifying transfers to data acquisition unit;
Described data acquisition unit is finished signals collecting, anti-mixed repeatedly digital filtering and high-speed cache synchronously the sensor signal in vibration and the loop electric weight is gathered and pre-service, and the vibration response signal data that obtain after will handling transfer to kernel control module by high-speed bus;
The sample frequency of this data acquisition unit and sampling length are adjusted by described kernel control module control;
Described kernel control module carries out spectrum analysis to the vibration response signal data that receive, show and the resonance frequency curve of record Transformer Winding on frequency domain, with the resonance frequency curve that before measured and write down, and the vibration frequency curve of transformer three-phase coil compares, judge the state of Transformer Winding, obtain measurement result.
The sweep frequency power source excitation that utilizes that the utility model provides detects the device of transformer winding state, and concrete testing process is as follows:
1, with the low pressure short circuit in winding of tested transformer, the frequency-conversion constant-current source is applied to the high-pressure side of testing transformer by an exciting transformer with output signal, and simultaneously tested Transformer Winding is exported this swept frequency excitation signal;
2, amplify by charge amplifier by the vibration response signal of vibration transducer measuring transformer winding, and with the vibration signal that records, again by being sent to kernel control module after the data acquisition unit acquisition process for the swept frequency excitation signal;
A kind of device that utilizes sweep frequency power source excitation to detect transformer winding state that the utility model provides, the variation of the natural resonance frequency curve by analyzing Transformer Winding detects the loosening situation of winding, can effective, highly sensitively detect the loosening and distortion situation of Transformer Winding, maintenance in time or replacing are avoided damaging the fault that causes transformer generation suddenly-applied short circuit because of winding construction.
Description of drawings
Fig. 1 is the instrumentation plan of background technology short circuit impedance method;
Fig. 2 is the equivalent two-port network of Transformer Winding in the background technology frequency response method;
Fig. 3 is a kind of structural representation that utilizes sweep frequency power source excitation to detect the device of transformer winding state that the utility model provides;
Fig. 4 is the comparison of transformer horizontal direction three-phase rumble spectrum in the utility model specific embodiment;
Fig. 5 is the comparison of transformer vertical direction three-phase vibration frequency in the utility model specific embodiment.
Embodiment
Followingly specify a kind of preferred forms of the present utility model according to Fig. 3～Fig. 5:
The sweep frequency power source excitation that utilizes that the utility model provides detects the device of transformer winding state, with the Transformer Winding equivalence is the elastic system of the complexity of a lumped parameter, when Transformer Winding produces loosening, when its axial pre tightening force changes, the natural frequency of the mechanical vibration on its former rank can progressively move to lower frequency direction, and the phenomenon that increases of the whole amplitude that low-frequency range is arranged, the vibration characteristics of whole elastic system is changed; And Transformer Winding can cause the variation of elastic system structure when deforming, thereby the vibration characteristics of elastic system is changed.Therefore, change, analyze the variation of the natural resonance frequency curve of Transformer Winding, just can detect the situation that Transformer Winding is loosening and be out of shape as long as can detect the vibration characteristics of elastic system itself effectively.
As shown in Figure 3, be that the sweep frequency power source excitation that utilizes that the utility model provides detects the device of transformer winding state, it comprises kernel control module 301, exciting module and data acquisition and control module;
Described exciting module comprises frequency-conversion constant-current source 201 and the exciting transformer 202 that connects by circuit;
Described data acquisition and control module comprises vibration transducer 101, charge amplifier 102, the data acquisition unit 103 of circuit connection successively;
Described frequency-conversion constant-current source 201 connects described kernel control module 301 by circuit, it is applied to the high-pressure side of detected transformer 4 by exciting transformer 202 with the electric current swept frequency excitation signal of exporting, and simultaneously tested Transformer Winding is exported this swept frequency excitation signal;
The amplitude size of the electric current swept frequency excitation signal of these frequency-conversion constant-current source 201 outputs, the swept frequency range of output frequency and sweep velocity are adjusted by described kernel control module 301 controls;
Described exciting transformer 202 is done impedance matching;
Described vibration transducer 101 is arranged on the housing of transformer 4, and it measures the vibration response signal of tested Transformer Winding under different excited frequencies, and the signal that records is transferred to charge amplifier 102:
Described charge amplifier 102 amplifies vibration response signal, and the vibration response signal after will amplifying transfers to data acquisition unit 103;
Described data acquisition unit 103 is finished signals collecting, anti-mixed repeatedly digital filtering and high-speed cache synchronously the sensor signal in vibration and the loop electric weight is gathered and pre-service, and the vibration response signal data that obtain after will handling transfer to kernel control module 301 by high-speed bus;
The sample frequency of this data acquisition unit 103 and sampling length are adjusted by described kernel control module 301 controls;
The vibration response signal data that 301 pairs of described kernel control modules receive are carried out spectrum analysis, show and the resonance frequency curve of record Transformer Winding on frequency domain, with the resonance frequency curve that before measured and write down, and the vibration frequency curve of transformer three-phase coil compares, judge the state of Transformer Winding, obtain measurement result.
The sweep frequency power source excitation that utilizes that the utility model provides detects the device of transformer winding state, and concrete testing process is as follows:
1, with the low pressure short circuit in winding of tested transformer 4, frequency-conversion constant-current source 201 is applied to the high-pressure side of testing transformer 4 by an exciting transformer 202 with output signal, and simultaneously tested Transformer Winding is exported this swept frequency excitation signal;
2, pass through the vibration response signal of vibration transducer 101 measuring transformer windings, and the vibration signal that records is amplified by charge amplifier 102, again by being sent to kernel control module 301 after data acquisition unit 103 acquisition process for the swept frequency excitation signal;
Step 3,301 pairs of data that receive of kernel control module are carried out spectrum analysis, obtain the resonance frequency curve of Transformer Winding, it was compared with former recording curve, or compare with the curve of transformer three-phase coil, when the Oscillation Amplitude of this frequency curve obviously amplifies, obviously skew takes place in spectrum peak, when unusual peak value promptly occurring, illustrate that this Transformer Winding has abnormal response, judge that Transformer Winding is under the abnomal condition, take place loosening or distortion, need in time to change, guarantee that circuit does not break down.
The sweep frequency power source excitation that utilizes that the utility model provides detects the device of transformer winding state, the variation of the natural resonance frequency curve by analyzing Transformer Winding detects the loosening situation of winding, can effective, highly sensitively detect the loosening and distortion situation of Transformer Winding, maintenance in time or replacing are avoided damaging the fault that causes transformer generation suddenly-applied short circuit because of winding construction.
Specific embodiment:
In certain transformer station, the A phase low-pressure side of main-transformer suffers short-circuit impact because of the outlet rheology takes place to puncture, pressure relief device protection action.The back is because of system's allotment reason, and decision puts into operation again.
Having carried out once having a power failure before operation and having detected, at first having adopted short circuit impedance method to test, short-circuit impedance do not change substantially (changing value is less than 0.1%) is found in test.Adopt the FRA method that transformer A phase low pressure winding is carried out test analysis again, finding does not have ANOMALOUS VARIATIONS with former measurement curve contrast.According to the conclusion of these 2 kinds of electrical measuring methods, think the transformer A phase winding coil fault that do not deform.
But, adopt device of the present utility model to detect at last, utilize the method for swept frequency excitation rumble spectrum, the winding of transformer three-phase has been done careful sweep check, obtain three-phase rumble spectrum curve as shown in Figure 4 and Figure 5, the vibration amplitude of finding transformer A phase and B mutually and the C amplification several times of comparing, the tangible skew of peak value generation of frequency spectrum, tangible unusual peak value has appearred, with the B that is not hit, C mutually frequency spectrum compared obviously unusual.
This shows, the utlity model has highly sensitive detection performance.
On May 24th, 2005, No. 3 main transformer A of Wuwei transformer station of Shanghai UHV (ultra-high voltage) company phase low-pressure side suffers short-circuit impact because of the outlet rheology takes place to puncture, pressure relief device protection action.Because of system's allotment reason, put into operation heavily again.
Morning May 26, power failure detected, and UHV (ultra-high voltage) company adopts short circuit impedance method to test, short-circuit impedance do not change substantially (changing value is less than 0.1%).Adopted the FRA method that transformer A phase low pressure winding is carried out test analysis by the East China pilot scale, do not found to have ANOMALOUS VARIATIONS with former measurement curve contrast.The range of influence power supply soon because bus connection switch breaks down need judge immediately to morning on the 26th, can not think the coil fault that deforms according to the conclusion of electrical measuring method, so transformer puts into operation again.
But outage is adopted the method for swept frequency excitation rumble spectrum by Shanghai Communications University's test group, find the A phase vibration amplitude amplification several times of comparing with C, significantly skew takes place in the peak value of frequency spectrum, owing to do not carry out sweep measurement it is pressed for time meticulously at that time, cause to obtain the whole spectrum curve and analyze.
Because this transformer dispatches from the factory early, through maintenance, this is exported short-circuit impact in addition, and pressure relief device has the protection action to take place, and the vibration amplitude of A phase with photograph C is compared obvious increase, so June 2 is out of service with this transformer.
June 7, after No. 3 main transformers in Wuwei station are out of service, we adopt the frequency sweep excitation method that the winding of transformer three-phase has been done careful sweep check, Fig. 4 and Fig. 5 compare for the spectrum curve that three-phase records, can see that tangible unusual peak value has appearred in the frequency spectrum that A vibrates mutually, with the B that is not hit, C mutually frequency spectrum compared obviously unusual.
Claims (3)
1. a device that utilizes sweep frequency power source excitation to detect transformer winding state is characterized in that, comprises kernel control module (301), exciting module and data acquisition and control module;
Described exciting module comprises frequency-conversion constant-current source (201) and the exciting transformer (202) that connects by circuit;
Described frequency-conversion constant-current source (201) connects described kernel control module (301) by circuit, it is applied to the high-pressure side of detected transformer (4) by exciting transformer (202) with the electric current swept frequency excitation signal of exporting, and simultaneously tested Transformer Winding is exported this swept frequency excitation signal;
Described data acquisition and control module comprises vibration transducer (101), charge amplifier (102), the data acquisition unit (103) of circuit connection successively;
Described vibration transducer (101) is arranged on the housing of transformer (4), and it measures the vibration response signal of tested Transformer Winding under different excited frequencies, and transfers to charge amplifier (102);
Described charge amplifier (102) amplifies vibration response signal, and transfers to data acquisition unit (103);
Described data acquisition unit (103) is finished signals collecting, anti-mixed repeatedly digital filtering and high-speed cache synchronously the sensor signal in vibration and the loop electric weight is gathered and pre-service, and the vibration response signal data that obtain after will handling transfer to kernel control module (301) by high-speed bus;
Described kernel control module (301) carries out spectrum analysis to the vibration response signal data that receive, show and the resonance frequency curve of record Transformer Winding on frequency domain, with the resonance frequency curve that before measured and write down, and the vibration frequency curve ratio of transformer three-phase coil, judges the state of Transformer Winding.
2. the device that utilizes sweep frequency power source excitation to detect transformer winding state as claimed in claim 1, it is characterized in that, the amplitude size of the electric current swept frequency excitation signal of frequency-conversion constant-current source (201) output, the swept frequency range of output frequency and sweep velocity are adjusted in described kernel control module (301) control.
3. the device that utilizes sweep frequency power source excitation to detect transformer winding state as claimed in claim 1 is characterized in that, the sample frequency and the sampling length of data acquisition unit (103) adjusted in described kernel control module (301) control.
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| Application Number | Priority Date | Filing Date | Title |
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| CN 200520047055 CN2864705Y (en) | 2005-11-30 | 2005-11-30 | Device for detecting transformer winding state utilizing sweep frequency power source exciting |
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| Application Number | Priority Date | Filing Date | Title |
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| CN 200520047055 CN2864705Y (en) | 2005-11-30 | 2005-11-30 | Device for detecting transformer winding state utilizing sweep frequency power source exciting |
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| CN2864705Y true CN2864705Y (en) | 2007-01-31 |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100373166C (en) * | 2005-11-30 | 2008-03-05 | 上海市电力公司 | Device for detecting transformer winding state utilizing sweep frequency power source exciting |
| WO2009138370A1 (en) * | 2008-05-14 | 2009-11-19 | Abb Research Ltd | A method and a device for estimating the clamping force on a winding package of a transformer or a reactor |
| WO2010060253A1 (en) * | 2008-11-25 | 2010-06-03 | 上海市电力公司 | The system and method for detecting the state of the transformer winding by utilizing excitation of the constant current sweep frequency power source |
| WO2011000134A1 (en) * | 2009-06-30 | 2011-01-06 | 上海市电力公司 | Method for detecting transformer winding state utilizing vibration waveform |
| CN102998544A (en) * | 2011-09-16 | 2013-03-27 | 河南电力试验研究院 | Method for diagnosing operating state of windings in short-circuiting of transformer |
| CN107102245A (en) * | 2017-06-09 | 2017-08-29 | 云南电网有限责任公司电力科学研究院 | Deformation of transformer winding and condenser bushing failure detector and method |
-
2005
- 2005-11-30 CN CN 200520047055 patent/CN2864705Y/en not_active Expired - Lifetime
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100373166C (en) * | 2005-11-30 | 2008-03-05 | 上海市电力公司 | Device for detecting transformer winding state utilizing sweep frequency power source exciting |
| WO2009138370A1 (en) * | 2008-05-14 | 2009-11-19 | Abb Research Ltd | A method and a device for estimating the clamping force on a winding package of a transformer or a reactor |
| CN102027660B (en) * | 2008-05-14 | 2013-09-11 | Abb研究有限公司 | Method and device for estimating the clamping force on a winding package of a transformer or reactor |
| US9099913B2 (en) | 2008-05-14 | 2015-08-04 | Abb Research Ltd. | Method and device for estimating the clamping force on a winding package of a transformer or a reactor |
| WO2010060253A1 (en) * | 2008-11-25 | 2010-06-03 | 上海市电力公司 | The system and method for detecting the state of the transformer winding by utilizing excitation of the constant current sweep frequency power source |
| CN101738567B (en) * | 2008-11-25 | 2012-05-30 | 上海市电力公司 | Method for detecting transformer winding state by using constant-current sweep frequency power source excitation |
| WO2011000134A1 (en) * | 2009-06-30 | 2011-01-06 | 上海市电力公司 | Method for detecting transformer winding state utilizing vibration waveform |
| CN102998544A (en) * | 2011-09-16 | 2013-03-27 | 河南电力试验研究院 | Method for diagnosing operating state of windings in short-circuiting of transformer |
| CN107102245A (en) * | 2017-06-09 | 2017-08-29 | 云南电网有限责任公司电力科学研究院 | Deformation of transformer winding and condenser bushing failure detector and method |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned |
Effective date of abandoning: 20080305 |
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| C25 | Abandonment of patent right or utility model to avoid double patenting |