CN103558526A - Method for detection of partial discharge of switch cabinet - Google Patents

Method for detection of partial discharge of switch cabinet Download PDF

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Publication number
CN103558526A
CN103558526A CN201310560225.8A CN201310560225A CN103558526A CN 103558526 A CN103558526 A CN 103558526A CN 201310560225 A CN201310560225 A CN 201310560225A CN 103558526 A CN103558526 A CN 103558526A
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CN
China
Prior art keywords
partial discharge
point
shelf depreciation
switchgear
switch cabinet
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Pending
Application number
CN201310560225.8A
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Chinese (zh)
Inventor
薛明
殷怡杰
朱启扬
徐力扬
黄成军
郭灿新
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
SHANGHAI HUACHENG ELECTRICAL TECHNOLOGY Co Ltd
State Grid Shanghai Electric Power Co Ltd
Original Assignee
SHANGHAI HUACHENG ELECTRICAL TECHNOLOGY Co Ltd
State Grid Shanghai Electric Power Co Ltd
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Application filed by SHANGHAI HUACHENG ELECTRICAL TECHNOLOGY Co Ltd, State Grid Shanghai Electric Power Co Ltd filed Critical SHANGHAI HUACHENG ELECTRICAL TECHNOLOGY Co Ltd
Priority to CN201310560225.8A priority Critical patent/CN103558526A/en
Publication of CN103558526A publication Critical patent/CN103558526A/en
Pending legal-status Critical Current

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Abstract

The invention discloses a method for detection of partial discharge of a switch cabinet in the field of power grids. The method for detection of partial discharge of the switch cabinet comprises the steps that initial locating of a partial discharge point is conducted, namely the general position of the partial discharge point of the switch cabinet is determined through two ultrahigh-frequency sensors; accurate locating of the partial discharge point is conducted, namely the accurate position of the partial discharge point of the switch cabinet is determined through multiple ultrasonic sensors; phasing of the partial discharge point is conducted, namely phasing is conducted on the partial discharge point of the switch cabinet through a high-frequency current sensor. The method for detection of partial discharge of the switch cabinet has the advantages that the problem of interference exiting in the process of detection of partial discharge of the switch cabinet is effectively solved, the credibility of a detection result is improved, accurate locating and phasing of the discharge position are achieved, position locating of the partial discharge point of the switch cabinet is accurate to the centimeter level, the type of partial discharge is determined, and engineering technicians can quite conveniently grasp the operation conditions of the switch cabinet.

Description

A kind of partial discharge of switchgear detection method
Technical field
The present invention relates to a kind of partial discharge of switchgear detection method in electrical network field.
Background technology
The insulating capacity of switch cubicle is the key factor that determine switch cabinet can safe and stable operation.The safe operation of electric system in the insulation fault serious threat that the deficiency of switch cubicle field testing procedure and the switch cubicle putting into operation occur.Partial Discharge Detection is the effective means of reflection switch cubicle insulation status, is also the focus of current research.For partial discharge of switchgear, detect, conventional is acoustoelectric wave checkout equipment at present, adopt ultrasonic sensor to be connected oscillograph with ultrahigh-frequency current sensor, oscillograph connects computing machine, acoustoelectric wave checkout equipment directly characterizes the intensity of shelf depreciation activity with the form of dB, have simple to operately, the clear and definite feature of rule, is subject to field operator's welcome deeply.Yet shelf depreciation is faint electrical phenomena, in testing process, be very easily subject to the impact of external interference, if can not effectively identify, disturb and got rid of, by the correctness and the validity that are difficult to guarantee that Partial Discharge Data is analyzed.In addition, the positioning function of existing acousto-electric detection equipment is simple, can only realize the coarse localization of switch cabinet body in single point of discharge situation, for the accurate location phasing of many point of discharges and inside switch cabinet, all be difficult to realize, this has greatly reduced the validity of location and the efficiency of maintenance.For this reason, the application of other detection technique of expansion research aspect switch cubicle is necessary.
Summary of the invention
The object of the invention is, in order to overcome the deficiencies in the prior art, provides a kind of partial discharge of switchgear detection method, and it can accurately locate phasing to partial discharge of switchgear, and accurately determines the type of partial discharge of switchgear.
A kind of technical scheme that realizes above-mentioned purpose is: a kind of partial discharge of switchgear detection method, comprises the following steps:
Shelf depreciation point Primary Location step a: uhf sensor is respectively placed at the two ends at the prefabricated head of the three-phase of switch cubicle, the ultrahigh frequency electromagnetic signal that receiving key cabinet shelf depreciation point produces, and two described ultrahigh frequency electromagnetic signals are presented on oscillograph, adjust two described uhf sensors in the position at prefabricated two ends of described three-phase, make the waveform life period of two described ultrahigh frequency electromagnetic signals on described oscillograph poor, according to the position of described mistiming compute switch cabinet shelf depreciation point;
Shelf depreciation is put accurate positioning step: close uhf sensor, by being positioned at the ultrasonic signal that on switch cabinet wall, a plurality of ultrasonic sensor receiving key cabinet shelf depreciation points of diverse location produce, and described ultrasonic signal is transformed into ultrasonic electrical signal, be presented on described oscillograph, according to the time delay between different ultrasonic electrical signals, the exact position of compute switch cabinet shelf depreciation point;
Shelf depreciation point phasing step: the current pulse signal that gathers partial discharge of switchgear point by being positioned at High Frequency Current Sensor on each single-phase electricity cable screen layer of three-phase electricity cable, and described current pulse signal is converted into voltage pulse signal is presented on spectrum analyzer, the phase place according to described voltage pulse signal on described spectrum analyzer is put phasing to partial discharge of switchgear.
Further, in shelf depreciation point Primary Location step, the calculating of partial discharge of switchgear point position, shelf depreciation is put the calculating of partial discharge of switchgear point exact position in accurate positioning step, and in shelf depreciation point phasing step, the phasing of partial discharge of switchgear point all completes by computing machine.
Further, in described shelf depreciation point phasing step, also on the shielding layer grounding line of three-phase electricity cable or armor ground wire, High Frequency Current Sensor is set, gather the current pulse signal of partial discharge of switchgear point, and be presented at described spectrum analyzer after described current pulse signal is converted into voltage pulse signal.
Adopted the technical scheme of a kind of partial discharge of switchgear detection method of the present invention, first with two uhf sensors, determine the approximate location of partial discharge of switchgear point, with a plurality of ultrasonic sensors, determine again the exact position of partial discharge of switchgear point, finally the technical scheme to partial discharge of switchgear point phasing by High Frequency Current Sensor.Its technique effect is: efficiently solve interference problem in partial discharge of switchgear testing process, improve the confidence level of testing result; And can accurately locate phasing to discharge position, and the registration of partial discharge of switchgear point is arrived to centimetre-sized, and determine the type of judgement shelf depreciation, greatly facilitate the operation conditions that engineering technical personnel grasp switch cubicle.
Accompanying drawing explanation
Fig. 1 is the structural representation of the pick-up unit that adopts in a kind of partial discharge of switchgear method of the present invention.
Fig. 2 is the process flow diagram of a kind of partial discharge of switchgear method of the present invention.
Embodiment
Refer to Fig. 1 and Fig. 2, the present inventor is in order to understand technical scheme of the present invention better, below by embodiment particularly, and is described in detail by reference to the accompanying drawings:
Refer to Fig. 1 and Fig. 2, the pick-up unit adopting described in a kind of partial discharge of switchgear detection method of the present invention, comprise switch cubicle 1 and three-phase electricity cable 2, switch cubicle 1 comprises prefabricated 12 of cabinet wall 11 and three-phase, the corresponding connection of each single-phase prefabricated head in prefabricated 12 of each single-phase electricity cable in three-phase electricity cable 2 and three-phase; Partial discharge of switchgear pick-up unit also comprises ultrasound wave (AE) sensor 3, high-frequency current (HFCT) sensor 4, ultrahigh frequency (UHF) sensor 5, oscillograph 6, spectrum analyzer 7 and computing machine 8.
Wherein, ultrasonic sensor 3 is located on the cabinet wall 11 of switch cubicle 1, and is movably; Uhf sensor 5 is positioned at prefabricated 12 of three-phase around, and is also movably.Ultrasonic sensor 3 is all connected oscillograph 6 with uhf sensor 5.
In the present embodiment, the oscillograph 6 adopting is TDS680 type digital storage oscilloscope, and the waveform of the ultrasonic electrical signal being passed over ultrahigh frequency electromagnetic signal that uhf sensor 5 is gathered and ultrasonic sensor 3 carries out real-time storage, records and calls.Ultrasonic sensor 3 is all connected with oscillograph 6 by ZigBee-network with uhf sensor 5, improves the property easy to use of this pick-up unit.
High Frequency Current Sensor 4 is fixed on the screen layer of each single-phase electricity cable in three-phase electricity cable 2, on the body of three-phase electricity cable 2, also can be fixed on the shielding layer grounding line 21 of three-phase electricity cable 2 or on armor ground wire 22.All High Frequency Current Sensor 4 connect spectrum analyzer 7.
Oscillograph 6 is all connected with computing machine 8 by bus or Wlan wireless network with spectrum analyzer 7, wherein uses Wlan network can realize the remote monitoring of pick-up unit to partial discharge of switchgear.
Pincerlike High Frequency Current Sensor folder (not shown) makes High Frequency Current Sensor 4 by being clamped to the cable body of three-phase electricity cable 2, or shielding layer grounding line 21, or on armor ground wire 22.High Frequency Current Sensor 4 is connected by bus or ZigBee-network with spectrum analyzer 7, wherein uses Zigbee network, and the use of this pick-up unit is more convenient.
A kind of partial discharge of switchgear detection method of the present invention, comprises three steps:
The first step is shelf depreciation point Primary Location step: when inside switch cabinet generation shelf depreciation, the rising edge of discharge pulse is very steep, <1ns current rise time along shelf depreciation path, pulse width mostly is nanosecond, can encourage ultrahigh frequency electromagnetic signal more than 1GHz.Ultrahigh frequency electromagnetic signal is at spatial, and prefabricated 12 of three-phase by the switch cubicle 1 installed ultrahigh frequency (UHF) sensor 5 around just can receive ultrahigh frequency electromagnetic signal.In ultrahigh frequency electromagnetic signal propagation process, for the uhf sensor 5 of diverse location, the time that different uhf sensors 5 receive ultrahigh frequency electromagnetic signal is different.It is poor that uhf sensor 5 receives ultrahigh frequency electromagnetic signal life period.The positioning principle of shelf depreciation point Primary Location step is, at switch cubicle 1, partial discharge position occurs, be the two ends of prefabricated 12 of three-phase, in Fig. 1, for two ends, left and right, respectively place a uhf sensor 5, and whether the ultrahigh frequency electromagnetic signal of observing 5 receptions of two uhf sensors on oscillograph 6 is poor if having time, have can compute switch cabinet shelf depreciation point approximate location, do not adjust the wherein position of any one uhf sensor 5, until it is poor to observe two ultrahigh frequency electromagnetic signal life periods on oscillograph 6.Then the position of compute switch cabinet shelf depreciation point.The calculating of the position of partial discharge of switchgear point completes by computing machine 8.Yet owing to being subject to the impact of the factors such as ultrahigh frequency electromagnetic signal propagation path and uhf sensor 5 positions, the often accurately identification of ultrahigh frequency electromagnetic signal initial time, can only carry out Primary Location, is difficult to realize the accurate location of partial discharge of switchgear point.
In addition on the one hand, uhf sensor 5 can detect the excitation signal that partial discharge of switchgear point produces, it is ultrahigh frequency electromagnetic signal, this excitation signal is that frequency is at UHF frequency band, be the electromagnetic wave of 300M~3GHz, due to common undesired signal, its frequency is all under 300MHz, the ultrahigh frequency electromagnetic signal that uhf sensor 5 detects has unrivaled interference free performance, contributes to get rid of the undesired signal running into when shelf depreciation point detects.
Second step, shelf depreciation is put accurate positioning step, close uhf sensor 5 and open ultrasonic sensor 3, generation along with partial discharge of switchgear point shelf depreciation, be accompanied by explosion shape ultrasonic signal and produce, and propagate to surrounding medium, by the ultrasonic sensor 3 being arranged on the cabinet wall 11 of switch cubicle 1, accept this ultrasonic signal, ultrasonic sensor 3 ultrasonic signals are converted to ultrasonic electrical signal, are presented on oscillograph 6.
Ultrasound wave location is to propagate into each sonac 3 on the cabinet wall 11 that is positioned at switch cubicle 1 by measuring the ultrasonic signal of local discharge generation, and on oscillograph 6, observe each ultrasonic sensor 3 and on oscillograph 6, produce the time delay between ultrasonic electrical signal, according to described time delay and ultrasonic propagation velocity, utilize the exact position of the method compute switch cabinet shelf depreciation point of space analysis geometry, realize the accurate location of partial discharge of switchgear point, although it is larger that ultrasound wave is decayed in power equipment common used material medium, measure effective range less, but accurate location that can shelf depreciation point.
In a kind of partial discharge of switchgear detection method of the present invention, first adopt the capable one-time positioning analysis of 5 pairs of local point of discharges of uhf sensor, determine the approximate range of shelf depreciation point, with the adverse effect excluding the interference signal and ultrasonic signal decay brings, then adopt ultrasonic sensor 3 to carry out secondary positioning analysis, realize the accurate location of partial discharge of switchgear point.The ultrahigh frequency electromagnetic signal and the ultrasonic electrical signal that due to while detector switch cabinet shelf depreciation point, produce like this, therefore by the signal analysis that two kinds of sensors are detected, can more effectively get rid of on-the-spot interference, improve shelf depreciation positioning precision, and by the waveform of ultrahigh frequency electromagnetic signal and ultrasonic electrical signal, determine the accuracy of the type identification of partial discharge of switchgear.
The 3rd step is shelf depreciation point phasing step, and High Frequency Current Sensor 4 utilizes electromagnetic induction coupling principle to detect the high-frequency current pulse of the partial discharge of switchgear point that flows to the earth.High-frequency current pulse is converted into HF voltage pulse and passes to spectrum analyzer 7.Waveform and the phase place of the HF voltage pulse receiving according to spectrum analyzer 7, computing machine 8 can carry out accurate phasing location to partial discharge of switchgear point, and the type of definite shelf depreciation.In the present embodiment, spectrum analyzer 7 is IFR2398 type spectrum analyzer, to improve the accuracy of spectrum analyzer 7 HF voltage pulses.
Because be also provided with High Frequency Current Sensor 4 on the shielding layer grounding line 21 of three-phase electricity cable 2 and armor ground wire 22, this height a kind of partial discharge of switchgear detection method of the present invention can be extracted the high-frequency current pulse of switch cubicle self, can obtain again from the high-frequency current pulse on three-phase electricity cable 2, be positioned at the partial discharge of switchgear point on threephase cable line 2.

Claims (3)

1. a partial discharge of switchgear detection method, comprises the following steps:
Shelf depreciation point Primary Location step a: uhf sensor is respectively placed at the two ends at the prefabricated head of the three-phase of switch cubicle, the ultrahigh frequency electromagnetic signal that receiving key cabinet shelf depreciation point produces, and two described ultrahigh frequency electromagnetic signals are presented on oscillograph, adjust two described uhf sensors in the position at prefabricated two ends of described three-phase, make the waveform life period of two described ultrahigh frequency electromagnetic signals on described oscillograph poor, according to the position of described mistiming compute switch cabinet shelf depreciation point;
Shelf depreciation is put accurate positioning step: close uhf sensor, by being positioned at the ultrasonic signal that on switch cabinet wall, a plurality of ultrasonic sensor receiving key cabinet shelf depreciation points of diverse location produce, and described ultrasonic signal is transformed into ultrasonic electrical signal, be presented on described oscillograph, according to the time delay between different ultrasonic electrical signals, the exact position of compute switch cabinet shelf depreciation point;
Shelf depreciation point phasing step: the current pulse signal that gathers partial discharge of switchgear point by being positioned at High Frequency Current Sensor on each single-phase electricity cable screen layer of three-phase electricity cable, and described current pulse signal is converted into voltage pulse signal is presented on spectrum analyzer, the phase place according to described voltage pulse signal on described spectrum analyzer is put phasing to partial discharge of switchgear.
2. a kind of partial discharge of switchgear detection method according to claim 1, it is characterized in that: in shelf depreciation point Primary Location step, the calculating of partial discharge of switchgear point position, shelf depreciation is put the calculating of partial discharge of switchgear point exact position in accurate positioning step, and in shelf depreciation point phasing step, the phasing of partial discharge of switchgear point all completes by computing machine.
3. a kind of partial discharge of switchgear detection method according to claim 1, it is characterized in that: in described shelf depreciation point phasing step, also on the shielding layer grounding line of three-phase electricity cable or armor ground wire, High Frequency Current Sensor is set, gather the current pulse signal of partial discharge of switchgear point, and be presented at described spectrum analyzer after described current pulse signal is converted into voltage pulse signal.
CN201310560225.8A 2013-11-12 2013-11-12 Method for detection of partial discharge of switch cabinet Pending CN103558526A (en)

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Cited By (9)

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Publication number Priority date Publication date Assignee Title
CN104808123A (en) * 2015-04-30 2015-07-29 国家电网公司 Switchgear partial discharge detecting system
CN105445634A (en) * 2015-12-28 2016-03-30 北京榕科电气有限公司 Partial discharge space positioning device and method
CN106370986A (en) * 2016-11-03 2017-02-01 合肥华义电气科技有限公司 Switch cabinet partial discharge monitoring method
CN108427068A (en) * 2018-03-29 2018-08-21 云南电网有限责任公司电力科学研究院 A kind of partial discharge of switchgear detection device and method
CN108445360A (en) * 2018-03-29 2018-08-24 云南电网有限责任公司电力科学研究院 A kind of partial discharge of switchgear positioning device and method
CN108535617A (en) * 2018-07-09 2018-09-14 闽江学院 A kind of partial discharge positioning method and positioning system of switchgear
CN109799432A (en) * 2019-02-01 2019-05-24 国网上海市电力公司 A kind of electrical equipment discharge fault positioning device
CN110658423A (en) * 2018-06-29 2020-01-07 Abb瑞士股份有限公司 Partial discharge monitoring system with compatibility function for voltage indication system
CN114280435A (en) * 2021-12-24 2022-04-05 重庆科技学院 Partial discharge management system of power system switch cabinet

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Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104808123A (en) * 2015-04-30 2015-07-29 国家电网公司 Switchgear partial discharge detecting system
CN105445634A (en) * 2015-12-28 2016-03-30 北京榕科电气有限公司 Partial discharge space positioning device and method
CN105445634B (en) * 2015-12-28 2023-08-08 北京榕科电气有限公司 Device and method for positioning partial discharge space
CN106370986A (en) * 2016-11-03 2017-02-01 合肥华义电气科技有限公司 Switch cabinet partial discharge monitoring method
CN108427068A (en) * 2018-03-29 2018-08-21 云南电网有限责任公司电力科学研究院 A kind of partial discharge of switchgear detection device and method
CN108445360A (en) * 2018-03-29 2018-08-24 云南电网有限责任公司电力科学研究院 A kind of partial discharge of switchgear positioning device and method
CN110658423A (en) * 2018-06-29 2020-01-07 Abb瑞士股份有限公司 Partial discharge monitoring system with compatibility function for voltage indication system
CN108535617A (en) * 2018-07-09 2018-09-14 闽江学院 A kind of partial discharge positioning method and positioning system of switchgear
CN109799432A (en) * 2019-02-01 2019-05-24 国网上海市电力公司 A kind of electrical equipment discharge fault positioning device
CN109799432B (en) * 2019-02-01 2021-06-22 国网上海市电力公司 Electrical equipment discharge fault positioning device
CN114280435A (en) * 2021-12-24 2022-04-05 重庆科技学院 Partial discharge management system of power system switch cabinet

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Application publication date: 20140205