CN204945316U - The harvester of live detection electromagnetic interference (EMI) is put in office of transformer station - Google Patents

The harvester of live detection electromagnetic interference (EMI) is put in office of transformer station Download PDF

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Publication number
CN204945316U
CN204945316U CN201520693506.5U CN201520693506U CN204945316U CN 204945316 U CN204945316 U CN 204945316U CN 201520693506 U CN201520693506 U CN 201520693506U CN 204945316 U CN204945316 U CN 204945316U
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China
Prior art keywords
signal
electromagnetic interference
emi
office
harvester
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Withdrawn - After Issue
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CN201520693506.5U
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Chinese (zh)
Inventor
谢耀恒
周卫华
李欣
叶会生
潘成
刘赟
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State Grid Corp of China SGCC
Electric Power Research Institute of State Grid Hunan Electric Power Co Ltd
State Grid Hunan Electric Power Co Ltd
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State Grid Corp of China SGCC
Electric Power Research Institute of State Grid Hunan Electric Power Co Ltd
State Grid Hunan Electric Power Co Ltd
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Application filed by State Grid Corp of China SGCC, Electric Power Research Institute of State Grid Hunan Electric Power Co Ltd, State Grid Hunan Electric Power Co Ltd filed Critical State Grid Corp of China SGCC
Priority to CN201520693506.5U priority Critical patent/CN204945316U/en
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Abstract

The utility model discloses the harvester that live detection electromagnetic interference (EMI) is put in office of a kind of transformer station, comprise electromagnetic interference signal sensing unit (1) and signal condition unit (2), described electromagnetic interference signal sensing unit (1) comprises UHF-antenna (11) for gathering coupled mode electromagnetic interference signal and transient earth voltage capacitive transducer (12), for detecting the high frequency Luo-coil (13) of conducted EMI signal, described UHF-antenna (11), transient earth voltage capacitive transducer (12), the output terminal of high frequency Luo-coil (13) is connected with signal condition unit (2) respectively.The utility model has the complex jamming signal that can gather and suppress to have band overlapping with Partial discharge signal, and accuracy in detection is high, detection sensitivity good, Site Detection advantage easily.

Description

The harvester of live detection electromagnetic interference (EMI) is put in office of transformer station
Technical field
The utility model relates to electric power project engineering field, be specifically related to the harvester that live detection electromagnetic interference (EMI) is put in office of a kind of transformer station, to the monitoring of background electromagnetic interference and record when carrying out shelf depreciation live detection for main equipments such as 35kV and above substation transformer, GIS, switch cubicle, cables.
Background technology
High voltage electric equipment such as transformer is the visual plant of electric system, its quality directly affects the safe operation of electrical network, the detection of shelf depreciation can reflect the insulation status of transformer, the insulation defect of Timeliness coverage inside transformer in advance, the generation of prevention latency and sudden accident.Detecting and assessing for shelf depreciation has become the important means of insulation status monitoring.Partial-discharge ultrahigh-frequency, high frequency, transient earth voltage detection method are applied increasingly extensively, for the equipment safety operations such as GIS, transformer, switch cubicle, cable and repair based on condition of component provide strong technical support.
Along with shelf depreciation live detection technology runs on-the-spot application at GIS, transformer, switch cubicle, cable, key technology problems also manifests gradually.As everyone knows, equipment runs the on-the-spot electromagnetic environment that often there is complexity, there are more randomness broadband, narrow-band interferer, suspension as mobile phone signal, radio or television signal, automobile motor, conductor corona, site operation electric welding machine and lighting source, high-voltage terminal end discharges, electric discharge in nearby device etc., and these are all put Site Detection to power equipment office and cause harsh electromagnetic to disturb.Therefore, for how to gather, analyze and suppress these complexity, have the undesired signal of band overlapping and improve detection sensitivity with Partial discharge signal, become the bottleneck of these detection method rig-site utilization.
Utility model content
The technical problems to be solved in the utility model: for the problems referred to above of prior art, there is provided a kind of can collection to suppress there is the complex jamming signal of band overlapping with Partial discharge signal, accuracy in detection be high, detection sensitivity good, Site Detection easily office of transformer station put the harvester of live detection electromagnetic interference (EMI).
In order to solve the problems of the technologies described above, the technical solution adopted in the utility model is:
The harvester of live detection electromagnetic interference (EMI) is put in office of a kind of transformer station, comprise electromagnetic interference signal sensing unit and signal condition unit, described electromagnetic interference signal sensing unit comprises UHF-antenna and transient earth voltage capacitive transducer for gathering coupled mode electromagnetic interference signal, for detecting the high frequency Luo-coil of conducted EMI signal, the output terminal of described UHF-antenna, transient earth voltage capacitive transducer, high frequency Luo-coil is connected with signal condition unit respectively.
Preferably, described signal condition unit comprises two signal sampling channels, the output terminal of described UHF-antenna is connected with the input end of a signal sampling channel, and the output terminal of described transient earth voltage capacitive transducer, the output terminal of high frequency Luo-coil are connected with the input end of another signal sampling channel respectively.
Preferably, described signal sampling channel comprises prime amplifier, directional coupler, wave detector and capture card, described prime amplifier is connected with the input end of directional coupler, and a road output terminal of described directional coupler is connected with capture card, another road output terminal is connected with capture card by wave detector.
Preferably, intermediate amplifier is provided with between described wave detector and capture card.
Preferably, the bandwidth of described UHF-antenna is 300M ~ 3000MHz, and the bandwidth of described transient earth voltage capacitive transducer is 3M ~ 100MHz, and the bandwidth of described high frequency Luo-coil is 1M ~ 30MHz.
Preferably, described UHF-antenna, transient earth voltage capacitive transducer, high frequency Luo-coil are connected with signal condition unit respectively by radio-frequency cable, the impedance of described radio-frequency cable is 50 ohm, and the characteristic impedance of described UHF-antenna, transient earth voltage capacitive transducer, high frequency Luo-coil three is 50 ohm.
Preferably, the output terminal of described signal condition unit is also connected with storage and display unit.
Preferably, one road input end of described storage and display unit is connected with the output terminal of signal condition unit, another road input end is also connected with reference signal collecting unit, described reference signal collecting unit comprises isolating transformer and attenuator, the primary side of described isolating transformer is connected with power frequency supply, and the secondary side of described isolating transformer is connected with the input end of storage and display unit by attenuator.
Preferably, the attenuation multiple of described attenuator is 100 times.
The harvester that live detection electromagnetic interference (EMI) is put in office of the utility model transformer station has following advantage: the utility model comprises electromagnetic interference signal sensing unit and signal condition unit, electromagnetic interference signal sensing unit comprises UHF-antenna for gathering coupled mode electromagnetic interference signal and transient earth voltage capacitive transducer, for detecting the high frequency Luo-coil of conducted EMI signal, UHF-antenna, transient earth voltage capacitive transducer, the output terminal of high frequency Luo-coil is connected with signal condition unit respectively, equally also can gather the complex jamming signal suppressing to have band overlapping with Partial discharge signal, can be used as the characteristic fingerprint storehouse of on-the-spot electromagnetic interference (EMI) identification, put live detection sensitivity for raising office and technological guidance is provided, there is accuracy in detection high, detection sensitivity is good, Site Detection is advantage easily.
Accompanying drawing explanation
Fig. 1 is the major architectural structural representation of the utility model embodiment device.
Fig. 2 is the detailed framework structural representation of the utility model embodiment device.
Fig. 3 is the framed structure schematic diagram of reference signal collecting unit in the utility model embodiment device.
Marginal data: 1, electromagnetic interference signal sensing unit; 11, UHF-antenna; 12, transient earth voltage capacitive transducer; 13, high frequency Luo-coil; 2, signal condition unit; 21, prime amplifier; 22, directional coupler; 23, wave detector; 24, capture card; 25, intermediate amplifier; 3, storage and display unit; 4, reference signal collecting unit; 41, isolating transformer; 42, attenuator.
Embodiment
As shown in Figure 1, the step that the acquisition method of live detection electromagnetic interference (EMI) is put in office of the present embodiment transformer station comprises: put the on-the-spot electromagnetic interference (EMI) travel path of live detection for office different, the sensor of coupled mode and conduction type is adopted to gather electromagnetic interference signal respectively, gather the coupled mode electromagnetic interference signal of tested electromagnetic interference (EMI) respectively by UHF-antenna UHF and transient earth voltage capacitive transducer TEV, gathered the conducted EMI signal of tested electromagnetic interference (EMI) by high frequency Luo-coil HF; Export after the coupled mode electromagnetic interference signal collected and conducted EMI signal are carried out signal condition respectively.
As shown in Figure 1, the harvester that live detection electromagnetic interference (EMI) is put in office of the present embodiment transformer station comprises electromagnetic interference signal sensing unit 1 and signal condition unit 2, electromagnetic interference signal sensing unit 1 comprises the UHF-antenna 11(UHF for gathering coupled mode electromagnetic interference signal) and transient earth voltage capacitive transducer 12(TEV), for detecting the high frequency Luo-coil 13(HF of conducted EMI signal), UHF-antenna 11, transient earth voltage capacitive transducer 12, the output terminal of high frequency Luo-coil 13 is connected with signal condition unit 2 respectively, by UHF-antenna 11, transient earth voltage capacitive transducer 12, high frequency Luo-coil 13 gathers the electromagnetic wave signal through spatial and the electromagnetic wave signal through wire spread.
As shown in Figure 2, in the present embodiment, signal condition unit 2 comprises two signal sampling channels, the output terminal (exporting UHF signal) of UHF-antenna 11 is connected with the input end of a signal sampling channel (being the signal sampling channel of upside in Fig. 2), and the output terminal (exporting TEV signal) of transient earth voltage capacitive transducer 12, the output terminal (exporting HF signal) of high frequency Luo-coil 13 are connected with the input end of another signal sampling channel (being the signal sampling channel of downside in Fig. 2) respectively.
As shown in Figure 2, signal sampling channel comprises prime amplifier 21, directional coupler 22, wave detector 23 and capture card 24, prime amplifier 21 is connected with the input end of directional coupler 22, and a road output terminal of directional coupler 22 is connected with capture card 24, another road output terminal is connected with capture card 24 by wave detector 23.Electromagnetic interference signal when signal condition unit 2, by prime amplifier 21 amplification filtering to improve the signal to noise ratio (S/N ratio) of signal; Through directional coupler 22, signal is divided into two-way again: a road signal does not deal with and directly enters capture card 24; Another road signal enters capture card 24 after wave detector 23, and wave detector 23 is for after carrying out low frequency process by signal.In the present embodiment, between wave detector 23 and capture card 24, be provided with intermediate amplifier 25.The second amplifying circuit to signal is constituted by prime amplifier 21 and intermediate amplifier 25.In the present embodiment, in the signal sampling channel of upside, the bandwidth of prime amplifier 21 is 300M ~ 3000MHz, gain is 40dB, the signal UHF collected for UHF-antenna 11 amplifies, and directional coupler 22 and wave detector 23 are respectively used to shunt and the detection of the signal UHF that UHF-antenna collects; The bandwidth of the prime amplifier 21 of downside signal sampling channel is 1M ~ 200MHz, gain is 40dB, the signal collected for transient earth voltage capacitive coupled sensors 12 and high frequency Luo-coil 13 amplifies, and directional coupler 22 and wave detector 23 are respectively used to shunt and the detection of the signal that capacitive coupled sensors TEV and high frequency Luo-coil HF collects; The sampling rate of capture card 24 is 50MSa/s, and sampling precision is 12Bit; The bandwidth of middle rank amplifier 25 is 0 ~ 100MHz, and gain is that 10 ~ 30dB is adjustable.It should be noted that, in the present embodiment two signal sampling channels be with two independently capture card 24 carry out exemplary illustration, certainly under this inspires, the signals collecting that those skilled in the art also can adopt same independently capture card 24 to realize two signal sampling channels as required, its principle is identical with the present embodiment.
In the present embodiment, the bandwidth of UHF-antenna 11 is 300M ~ 3000MHz, and the bandwidth of transient earth voltage capacitive transducer 12 is 3M ~ 100MHz, and the bandwidth of high frequency Luo-coil 13 is 1M ~ 30MHz.
In the present embodiment, UHF-antenna 11, transient earth voltage capacitive transducer 12, high frequency Luo-coil 13 are connected with signal condition unit 2 respectively by radio-frequency cable, the impedance of radio-frequency cable is 50 ohm, and the characteristic impedance of UHF-antenna 11, transient earth voltage capacitive transducer 12, high frequency Luo-coil 13 three is 50 ohm.In the present embodiment, the standing-wave ratio (SWR) of radio-frequency cable is less than 1.2, and radio-frequency cable two ends are N-50 type joint, bandwidth 0 ~ 3000MHz, can reduce the suppression to collecting signal to greatest extent.
As shown in Figure 2, the output terminal of signal condition unit 2 is also connected with storage and display unit 3, except baseband signal display translation, in the present embodiment, storage and display unit 3 can also show time domain waveform and frequency-domain waveform in real time, and acquisition relevant feature parameters can be calculated, such as 3 by carrying out mathematics manipulation by rectified signal, with phase impulse sequence PRPS, PHASE DISTRIBUTION PRPD, the modes such as time-frequency distributions are shown, extract relevant feature parameters, the fingerprint base of the on-the-spot electromagnetic interference (EMI) of live detection is put in formation office, by carrying out collection and the analysis of substation field electromagnetic interference (EMI), technically the waveform character grasping electromagnetic interference (EMI) will be conducive to, propagation characteristic, statistical nature, thus contribute to the office of searching and put on-the-spot interference and propose braking measure targetedly.It should be noted that, the basic function of storage and display unit 3 is the storage and the display that realize collection signal, the structure of storage and display unit 3 generally comprises controller and display module, the storage of collection signal is realized and display is ordinary skill in the art means by controller and display module, and show time domain waveform and frequency-domain waveform in real time, calculating and obtaining relevant feature parameters is only to the structural further improvement of the present embodiment, the enforcement of the present embodiment obviously and do not rely on real-time display time domain waveform and the frequency-domain waveform of storage and display unit 3, calculate and obtain relevant feature parameters, do not repeat them here.
As shown in Figure 2, one road input end of storage and display unit 3 is connected with the output terminal of signal condition unit 2, another road input end is also connected with reference signal collecting unit 4, reference signal collecting unit 4 comprises isolating transformer 41 and attenuator 42, the primary side of isolating transformer 41 is connected with power frequency supply, the secondary side of isolating transformer 41 is connected by the input end of attenuator 42 with storage and display unit 3, and isolating transformer 41 filters for the harmonic wave comprised by civil power, to provide standard reference signal.Reference signal collecting unit 4 gathers power-frequency voltage signal and exports storage and display unit 3 to as with reference to signal.In the present embodiment, the attenuation multiple of attenuator 42 is 100 times, is used for the secondary side voltage of isolating transformer 41 being carried out step-down, for storage and display unit 3 provides reference signal.
The above is only preferred implementation of the present utility model, protection domain of the present utility model be not only confined to above-described embodiment, and all technical schemes belonged under the utility model thinking all belong to protection domain of the present utility model.It should be pointed out that for those skilled in the art, do not departing from the some improvements and modifications under the utility model principle prerequisite, these improvements and modifications also should be considered as protection domain of the present utility model.

Claims (9)

1. the harvester of live detection electromagnetic interference (EMI) is put in an office of transformer station, it is characterized in that: comprise electromagnetic interference signal sensing unit (1) and signal condition unit (2), described electromagnetic interference signal sensing unit (1) comprises UHF-antenna (11) for gathering coupled mode electromagnetic interference signal and transient earth voltage capacitive transducer (12), for detecting the high frequency Luo-coil (13) of conducted EMI signal, described UHF-antenna (11), transient earth voltage capacitive transducer (12), the output terminal of high frequency Luo-coil (13) is connected with signal condition unit (2) respectively.
2. the harvester of live detection electromagnetic interference (EMI) is put in office of transformer station according to claim 1, it is characterized in that: described signal condition unit (2) comprises two signal sampling channels, the output terminal of described UHF-antenna (11) is connected with the input end of a signal sampling channel, and the output terminal of described transient earth voltage capacitive transducer (12), the output terminal of high frequency Luo-coil (13) are connected with the input end of another signal sampling channel respectively.
3. the harvester of live detection electromagnetic interference (EMI) is put in office of transformer station according to claim 2, it is characterized in that: described signal sampling channel comprises prime amplifier (21), directional coupler (22), wave detector (23) and capture card (24), described prime amplifier (21) is connected with the input end of directional coupler (22), and a road output terminal of described directional coupler (22) is connected with capture card (24), another road output terminal is connected with capture card (24) by wave detector (23).
4. the harvester of live detection electromagnetic interference (EMI) is put in office of transformer station according to claim 3, it is characterized in that: be provided with intermediate amplifier (25) between described wave detector (23) and capture card (24).
5. the harvester of live detection electromagnetic interference (EMI) is put in office of transformer station according to claim 4, it is characterized in that: the bandwidth of described UHF-antenna (11) is 300M ~ 3000MHz, the bandwidth of described transient earth voltage capacitive transducer (12) is 3M ~ 100MHz, and the bandwidth of described high frequency Luo-coil (13) is 1M ~ 30MHz.
6. the harvester of live detection electromagnetic interference (EMI) is put in office of transformer station according to claim 5, it is characterized in that: described UHF-antenna (11), transient earth voltage capacitive transducer (12), high frequency Luo-coil (13) are connected with signal condition unit (2) respectively by radio-frequency cable, the impedance of described radio-frequency cable is 50 ohm, and the characteristic impedance of described UHF-antenna (11), transient earth voltage capacitive transducer (12), high frequency Luo-coil (13) three is 50 ohm.
7. the harvester of live detection electromagnetic interference (EMI) is put in office of transformer station according to claim 6, it is characterized in that: the output terminal of described signal condition unit (2) is also connected with storage and display unit (3).
8. the harvester of live detection electromagnetic interference (EMI) is put in office of transformer station according to claim 7, it is characterized in that: a road input end of described storage and display unit (3) is connected with the output terminal of signal condition unit (2), another road input end is also connected with reference signal collecting unit (4), described reference signal collecting unit (4) comprises isolating transformer (41) and attenuator (42), the primary side of described isolating transformer (41) is connected with power frequency supply, the secondary side of described isolating transformer (41) is connected with the input end of storage and display unit (3) by attenuator (42).
9. the harvester of live detection electromagnetic interference (EMI) is put in office of transformer station according to claim 8, it is characterized in that: the attenuation multiple of described attenuator (42) is 100 times.
CN201520693506.5U 2015-09-09 2015-09-09 The harvester of live detection electromagnetic interference (EMI) is put in office of transformer station Withdrawn - After Issue CN204945316U (en)

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105116306A (en) * 2015-09-09 2015-12-02 国家电网公司 Acquisition method and device of substation partial discharge live detection electromagnetic interference
CN106771499A (en) * 2017-01-17 2017-05-31 中国电力科学研究院 The measuring system and method for the transient current that GIS isolator operations are formed
CN108548996A (en) * 2018-04-09 2018-09-18 国网天津市电力公司电力科学研究院 A method of the detection switch cabinet defect based on transient earth voltage and superfrequency
CN110907770A (en) * 2019-11-28 2020-03-24 深圳供电局有限公司 Partial discharge pulse feature extraction method and device, computer equipment and medium
CN111950410A (en) * 2020-07-31 2020-11-17 中铁第一勘察设计院集团有限公司 On-line electromagnetic environment monitoring device and method based on radio fingerprint identification

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105116306A (en) * 2015-09-09 2015-12-02 国家电网公司 Acquisition method and device of substation partial discharge live detection electromagnetic interference
CN105116306B (en) * 2015-09-09 2018-05-15 国家电网公司 The acquisition method and device of substation's partial discharge electrification detection electromagnetic interference
CN106771499A (en) * 2017-01-17 2017-05-31 中国电力科学研究院 The measuring system and method for the transient current that GIS isolator operations are formed
CN108548996A (en) * 2018-04-09 2018-09-18 国网天津市电力公司电力科学研究院 A method of the detection switch cabinet defect based on transient earth voltage and superfrequency
CN108548996B (en) * 2018-04-09 2020-07-28 国网天津市电力公司电力科学研究院 Method for detecting defects of switch cabinet based on transient ground voltage and ultrahigh frequency
CN110907770A (en) * 2019-11-28 2020-03-24 深圳供电局有限公司 Partial discharge pulse feature extraction method and device, computer equipment and medium
CN111950410A (en) * 2020-07-31 2020-11-17 中铁第一勘察设计院集团有限公司 On-line electromagnetic environment monitoring device and method based on radio fingerprint identification
CN111950410B (en) * 2020-07-31 2024-04-05 中铁第一勘察设计院集团有限公司 Online electromagnetic environment monitoring device and method based on radio fingerprint identification

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