CN102508124A - Detection method of partial discharge of electrical equipment and device thereof - Google Patents
Detection method of partial discharge of electrical equipment and device thereof Download PDFInfo
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- CN102508124A CN102508124A CN2011103151936A CN201110315193A CN102508124A CN 102508124 A CN102508124 A CN 102508124A CN 2011103151936 A CN2011103151936 A CN 2011103151936A CN 201110315193 A CN201110315193 A CN 201110315193A CN 102508124 A CN102508124 A CN 102508124A
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Abstract
The invention relates to a detection method partial discharge of electrical equipment and a device thereof. The detection method comprises the following steps of: erecting a measuring antenna in the position which is 20-30m away from the equipment to be detected, measuring an electromagnetic wave electric field component radiated from the electrical equipment, transmitting the measured signal waveform of the electromagnetic wave electric field component into a digital storage oscilloscope for storage, transmitting the signal waveform from the digital storage oscilloscope to a computer via a communication cable, performing Fourier decomposition on the signal waveform by application software of the computer to get a frequency spectrum characteristic curve of radiated electromagnetic waves, and performing contrastive analysis on the frequency spectrum characteristic curve according to the corresponding relation between a 1GHz-3GHz ultra-high frequency component and the partial discharge characteristic of the electrical equipment so as to identify and evaluate the partial discharge characteristic of the detected electrical equipment. The detection method has the following advantages: 1-3GHz ultra-high frequency signals of the radiated electromagnetic waves generated by the partial discharge are measured through an ultra-high frequency detection method, so that the detection is less affected by external interference signals, and reliability and sensitivity in detection of the partial discharge can be greatly improved.
Description
Technical field
The present invention relates to a kind of detection method for local discharge and device thereof, especially relate to a kind of local discharge of electrical equipment detection method and device thereof.
Background technology
At present, the detection of local discharge of electrical equipment characteristic and assessment can be divided into non-electrical measuring method and electrical measuring method two big classes by the physical quantity character that is detected.
Non-electrical measuring method detects the non-electrical phenomenas such as newly-generated thing of the ultrasound wave that produces in the shelf depreciation process, the light that sends, heat and appearance and discerns local discharge of electrical equipment; Electrical measuring method detects electric pulse, the electromagnetic radiation that produces in the shelf depreciation process, and the transfer of electric charge and the electrical phenomenas such as loss of electric energy are discerned local discharge of electrical equipment.No matter be that non-electrical measuring method or electrical measuring method all also exist all deficiencies; The pulse current method measuring method is simple the most widely as using in the electrical measuring method; Highly sensitive; It is quantitative to be easy to shelf depreciation, but because of the frequency of its detection signal generally at tens of kHz～tens of MHz, be subject to the influence of various electromagnetic interference (EMI).Ultrahigh frequency UHF detection method 1～3GHz in uhf-range extracts the ultra-high frequency signal that shelf depreciation produces; Thereby it is little influenced by external interference; Can greatly improve the reliability and the sensitivity of Partial Discharge Detection; But still have a lot of problems to wait to solve, have shortcomings such as accuracy rate is low, installation and maintenance difficulty like ultrahigh frequency detection methods such as present contact that adopts such as built-in sensors.
Summary of the invention
The present invention solves the existing in prior technology technical matters; A kind of radiated electromagnetic wave 1～3GHz ultra-high frequency signal that adopts ultrahigh frequency detection method measure local discharge generation is provided; Receive the external interference effect of signals little, can improve the reliability of Partial Discharge Detection and a kind of local discharge of electrical equipment detection method and the device thereof of sensitivity greatly.
It is to solve the existing in prior technology technical matters that the present invention also has a purpose; Provide a kind of contactless ultrahigh frequency detection method of external antenna that adopts to overcome shortcomings such as contact measurement method installation and maintenance difficulty, can be widely used in the on-line monitoring of various electrical equipments or a kind of local discharge of electrical equipment detection method and the device thereof of off-line fast inspection.
It is to solve the existing in prior technology technical matters that the present invention has a purpose again; Provide that a kind of contactless ultrahigh frequency detection method that adopts external antenna can be used for sending out, the shelf depreciation fast detecting in the transformer station under the electrical equipment no cut-off condition; Need not any wiring during measurement; Just can realize fast detecting, can improve a kind of local discharge of electrical equipment detection method and the device thereof of the utilization ratio of measuring equipment greatly local discharge of electrical equipment in whole, transformer station.
Above-mentioned technical matters of the present invention mainly is able to solve through following technical proposals:
A kind of local discharge of electrical equipment detection method is characterized in that, may further comprise the steps:
Step 1; Model test step: set up the partial discharge test model and carry out model test; Adopt digital storage oscilloscope to measure the shelf depreciation current waveform under the different discharge types through shunt; Adopt Matlab software that this current waveform is made Fourier transform again, obtain the typical frequency spectrum characteristic curve of local discharge of electrical equipment electric current;
Step 4; On-site measurement method step: setting up the measurement antenna from on-the-spot Devices to test 20m place; The electromagnetic wave electric field component that the measure field electrical equipment radiates, measured electromagnetic wave electric field component signal waveform is imported the digital storage oscilloscope storage into through concentric cable, and digital storage oscilloscope imports this signal waveform into computing machine through communication cable; Computing machine is made Fourier decomposition to this signal waveform; Obtain the actual spectrum family curve of measure field electrical equipment radiated electromagnetic wave, the radiation field intensity that records in corresponding relation comparison 1～3GHz UHF band of 3 set by step again confirms whether Devices to test produces shelf depreciation.
In above-mentioned a kind of local discharge of electrical equipment detection method, in the described step 4, the concrete operation method that obtains the actual spectrum characteristic curve is following:
Step 4.1 setting up the measurement antenna from electrical equipment to be measured 20 places, is measured the electromagnetic wave electric field component signal waveform that electrical equipment to be measured radiates, and measured electromagnetic wave electric field component signal waveform is imported the digital storage oscilloscope storage into through concentric cable;
Step 4.2; The digital storage oscilloscope electromagnetic wave electric field component signal waveform that step 4.1 is measured is imported computing machine into through communication cable; Computer application software obtains the correspondent frequency component to this electromagnetic wave electric field component signal waveform as Fourier decomposition, thereby obtains the actual spectrum characteristic curve of on-site electrical equipment radiated electromagnetic wave;
Step 4.3; The actual spectrum characteristic curve of the on-site electrical equipment radiated electromagnetic wave that comparison step 4.2 obtains; Like the radiation field intensity component that records in its 1～3GHz UHF band>0.1V/m, then shelf depreciation has taken place in determining apparatus, otherwise shelf depreciation does not take place.
In above-mentioned a kind of local discharge of electrical equipment detection method; In the said step 1; Need measure the shelf depreciation current waveform under the different discharge types, said different discharge types are respectively: pin-plate discharge, bubble-discharge, oil wedge discharge, surface-discharge, suspension discharge, the discharge of inner oil clearance.
In above-mentioned a kind of local discharge of electrical equipment detection method; In the step 2, the characteristic method of typical frequency spectrum of radiated electromagnetic wave is specially when obtaining local discharge of electrical equipment: adopt the electromagnetic field analysis FEKO of simulation software to set up model, according to the Fourier decomposition result of shelf depreciation electric current; In the frequency band range of 0～3GHz; Is at interval with 100MHz, gets the different frequency current weight successively and carry out simulation calculation, ask for the radiated electromagnetic wave electric field component of each respective frequencies point as the feed of Simulation Calculation; Adopt Matlab software that these calculated values are carried out match again, the spectral characteristic curve of radiated electromagnetic wave when obtaining local discharge of electrical equipment.
At above-mentioned a kind of on-site electrical equipment detection method for local discharge, in described step 3, the radiated electromagnetic wave high fdrequency component is 1GHz～3GHz ultrahigh frequency component.
A kind of device that uses the local discharge of electrical equipment detection method; It is characterized in that, comprise the measurement antenna that is used to measure electrical equipment electromagnetic wave electric field component signal waveform to be measured, use personal computer with the analysis of measuring digital storage oscilloscope that antenna is connected, be connected with digital storage oscilloscope through communication cable through concentric cable.
Therefore, the present invention has following advantage: 1. adopt the radiated electromagnetic wave 1-3GHz ultra-high frequency signal of ultrahigh frequency detection method measure local discharge generation, receive the external interference effect of signals little, can improve the reliability and the sensitivity of Partial Discharge Detection greatly; 2. adopt the contactless ultrahigh frequency detection method of external antenna can overcome shortcomings such as contact measurement method installation and maintenance difficulty, can be widely used in the on-line monitoring or the off-line fast inspection of various electrical equipments; 3. adopt that the contactless ultrahigh frequency detection method of external antenna can be used for sending out, the shelf depreciation fast detecting in the transformer station under the electrical equipment no cut-off condition; Need not any wiring during measurement; Just can realize fast detecting, can improve the utilization ratio of measuring equipment greatly local discharge of electrical equipment in whole, transformer station.
Description of drawings
Fig. 1 is that the present invention is according to the typical frequency spectrum characteristic curve diagram of analog reslt through the local discharge of electrical equipment electric current of Fourier decomposition acquisition.
Fig. 2 is the Fourier decomposition result of the present invention with the shelf depreciation electric current, gets the feed of different frequency current weight as Simulation Calculation, the typical frequency spectrum family curve of radiated electromagnetic wave when carrying out local discharge of electrical equipment that simulation calculation obtains.
Fig. 3 is a kind of workflow diagram of the present invention.
Embodiment
Pass through embodiment below, and combine accompanying drawing, do further bright specifically technical scheme of the present invention.
Embodiment:
A kind of local discharge of electrical equipment detection method may further comprise the steps:
Step 1; Set up the partial discharge test model and carry out model test; Adopt digital storage oscilloscope to measure the shelf depreciation current waveform under the different discharge types through shunt; Adopt Matlab software that this current waveform is made Fourier transform again, obtain the typical frequency spectrum characteristic curve of local discharge of electrical equipment electric current; Wherein, different discharge types are respectively: pin-plate discharge, bubble-discharge, oil wedge discharge, surface-discharge, suspension discharge, the discharge of inner oil clearance.The concrete operation method that obtains the typical frequency spectrum characteristic curve is following:
Step 1.1; Shunt is serially connected in the test model discharge loop; The shunt output terminal is connected with digital storage oscilloscope through concentric cable, the current waveform that produces during the discharge of experiment with measuring model, and measured current signal waveform is imported the digital storage oscilloscope storage into through concentric cable;
Step 1.2 adopts Matlab software that the current signal waveform in the digital storage oscilloscope is made Fourier decomposition, obtains the typical frequency spectrum characteristic curve of local discharge of electrical equipment electric current;
Step 4; On-site measurement method step: setting up the measurement antenna from on-the-spot Devices to test 20m place; The electromagnetic wave electric field component that the measure field electrical equipment radiates, measured electromagnetic wave electric field component signal waveform is imported the digital storage oscilloscope storage into through concentric cable, and digital storage oscilloscope imports this signal waveform into computing machine through communication cable; Computing machine is made Fourier decomposition to this signal waveform; Obtain the actual spectrum family curve of measure field electrical equipment radiated electromagnetic wave, the radiation field intensity that records in corresponding relation comparison 1～3GHz UHF band of 3 set by step again confirms whether Devices to test produces shelf depreciation; In the step 4, the concrete operation method that obtains the typical frequency spectrum characteristic curve is following:
Step 4.1 set up measurement antenna (2) from electrical equipment to be measured (1) 20-30m place, is measured
The electromagnetic wave electric field component signal waveform that electrical equipment to be measured (1) radiates, measured electromagnetic wave electric field component signal waveform is imported digital storage oscilloscope storage (3) into through concentric cable (5);
Step 4.2; Digital storage oscilloscope (3) the electromagnetic wave electric field component signal waveform that step 1 is measured is imported computing machine (4) into through communication cable (6); Computing machine (4) application software is obtained the correspondent frequency component to this electromagnetic wave electric field component signal waveform as Fourier decomposition, thereby obtains the typical frequency spectrum characteristic curve of radiated electromagnetic wave;
Step 4.3; The actual spectrum characteristic curve of the on-site electrical equipment radiated electromagnetic wave that comparison step 4.2 obtains; Like the radiation field intensity component that records in its 1～3GHz UHF band>0.1V/m, then shelf depreciation has taken place in determining apparatus, otherwise shelf depreciation does not take place.
In the present embodiment, the device of the local discharge of electrical equipment detection method above using comprises: comprise the measurement antenna 2 that is used to measure electrical equipment 1 electromagnetic wave electric field component signal waveform to be measured, through concentric cable 5 with measure digital storage oscilloscope 3 that antenna 2 is connected, pass through the computing machine 4 that communication cable 6 is connected with digital storage oscilloscope 3.
Specific embodiment described herein only is that the present invention's spirit is illustrated.Person of ordinary skill in the field of the present invention can make various modifications or replenishes or adopt similar mode to substitute described specific embodiment, but can't depart from spirit of the present invention or surmount the defined scope of appended claims.
Although this paper has used electrical equipment to be measured 1, measured terms such as antenna 2, digital storage oscilloscope 3, computing machine 4, concentric cable 5, communication cable 6 morely, do not get rid of the possibility of using other term.Using these terms only is in order to describe and explain the essence of the utility model more easily; It all is contrary with the utility model spirit being construed to any additional restriction to them.
Claims (6)
1. a local discharge of electrical equipment detection method is characterized in that, may further comprise the steps:
Step 1; Model test step: set up the partial discharge test model and carry out model test; Adopt digital storage oscilloscope to measure the shelf depreciation current waveform under the different discharge types through shunt; Adopt Matlab software that this current waveform is made Fourier transform again, obtain the typical frequency spectrum characteristic curve of local discharge of electrical equipment electric current;
Step 2; Emulation experiment step: different electrical equipments are set up cad model; Get the different frequency current weight that model test of partial discharge records among the Fourier decomposition result of electric current successively in the step 1 and carry out simulation calculation, the typical frequency spectrum family curve of radiated electromagnetic wave when obtaining local discharge of electrical equipment as the feed of Simulation Calculation;
Step 3; Confirm the corresponding relation between the Characteristics of Partial Discharge of radiated electromagnetic wave 1～3GHz ultrahigh frequency component and electrical equipment by step 2 simulation calculation result: when electrical equipment generation shelf depreciation; From Devices to test 20m place; In 1～3GHz UHF band, can record the radiation field intensity of 0.1V/m; When electrical equipment shelf depreciation did not take place, from Devices to test 20m place, in 1～3GHz UHF band, the radiation field intensity that records was zero;
Step 4; On-site measurement method step: setting up the measurement antenna from on-the-spot Devices to test 20m place; The electromagnetic wave electric field component that the measure field electrical equipment radiates, measured electromagnetic wave electric field component signal waveform is imported the digital storage oscilloscope storage into through concentric cable, and digital storage oscilloscope imports this signal waveform into computing machine through communication cable; Computing machine is made Fourier decomposition to this signal waveform; Obtain the actual spectrum family curve of measure field electrical equipment radiated electromagnetic wave, the radiation field intensity that records in corresponding relation comparison 1～3GHz UHF band of 3 set by step again confirms whether Devices to test produces shelf depreciation.
2. a kind of local discharge of electrical equipment detection method according to claim 1, its characteristic exists
In, in the described step 4, the concrete operation method that obtains the typical frequency spectrum characteristic curve is following:
Step 4.1 set up measurement antenna (2) from electrical equipment to be measured (1) 20-30m place, is measured
The electromagnetic wave electric field component signal waveform that electrical equipment to be measured (1) radiates, measured electromagnetic wave electric field component signal waveform is imported digital storage oscilloscope storage (3) into through concentric cable (5);
Step 4.2; Digital storage oscilloscope (3) the electromagnetic wave electric field component signal waveform that step 1 is measured is imported computing machine (4) into through communication cable (6); Computing machine (4) application software is obtained the correspondent frequency component to this electromagnetic wave electric field component signal waveform as Fourier decomposition, thereby obtains the typical frequency spectrum characteristic curve of radiated electromagnetic wave;
Step 4.3; The actual spectrum characteristic curve of the on-site electrical equipment radiated electromagnetic wave that comparison step 4.2 obtains; Like the radiation field intensity component that records in its 1～3GHz UHF band>0.1V/m, then shelf depreciation has taken place in determining apparatus, otherwise shelf depreciation does not take place.
3. a kind of local discharge of electrical equipment detection method according to claim 2; It is characterized in that; In the said step 1; Need measure the shelf depreciation current waveform under the different discharge types, said different discharge types are respectively: pin-plate discharge, bubble-discharge, oil wedge discharge, surface-discharge, suspension discharge, the discharge of inner oil clearance.
4. a kind of local discharge of electrical equipment detection method according to claim 1; It is characterized in that; In the step 2, the characteristic method of typical frequency spectrum of radiated electromagnetic wave is specially when obtaining local discharge of electrical equipment: adopt the electromagnetic field analysis FEKO of simulation software to set up model, according to the Fourier decomposition result of model test shelf depreciation electric current; In the frequency band range of 0～3GHz; Is at interval with 100MHz, gets the different frequency current weight successively and carry out simulation calculation, ask for the radiated electromagnetic wave electric field component of each respective frequencies point as the feed of Simulation Calculation; Adopt Matlab software that these calculated values are carried out match again, the spectral characteristic curve of radiated electromagnetic wave when obtaining local discharge of electrical equipment.
5. a kind of local discharge of electrical equipment detection method according to claim 1 is characterized in that, in described step 3, the radiated electromagnetic wave high fdrequency component is 1GHz～3GHz ultrahigh frequency component.
6. device that uses the described local discharge of electrical equipment detection method of claim 1; Comprise: it is characterized in that, comprise the measurement antenna (2) that is used to measure electrical equipment to be measured (1) electromagnetic wave electric field component signal waveform, through concentric cable (5) with measure digital storage oscilloscope (3) that antenna (2) is connected, pass through the computing machine (4) that communication cable (6) is connected with digital storage oscilloscope (3).
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Cited By (5)
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