CN105259479A - Grounding fault detection apparatus - Google Patents

Grounding fault detection apparatus Download PDF

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Publication number
CN105259479A
CN105259479A CN201510805795.8A CN201510805795A CN105259479A CN 105259479 A CN105259479 A CN 105259479A CN 201510805795 A CN201510805795 A CN 201510805795A CN 105259479 A CN105259479 A CN 105259479A
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China
Prior art keywords
coupled
resistance
operational amplifier
output terminal
signal
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CN201510805795.8A
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Chinese (zh)
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CN105259479B (en
Inventor
李藻
陈海宏
郑贤舜
夏陈喆
奚洪磊
郑晟
金海晨
夏惠惠
陈宜
林伟恺
金强
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WENZHOU TUSHENG TECHNOLOGY Co Ltd
State Grid Corp of China SGCC
State Grid Zhejiang Electric Power Co Ltd
Wenzhou Power Supply Co of State Grid Zhejiang Electric Power Co Ltd
Original Assignee
WENZHOU TUSHENG TECHNOLOGY Co Ltd
State Grid Corp of China SGCC
State Grid Zhejiang Electric Power Co Ltd
Wenzhou Power Supply Co of State Grid Zhejiang Electric Power Co Ltd
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Priority to CN201510805795.8A priority Critical patent/CN105259479B/en
Publication of CN105259479A publication Critical patent/CN105259479A/en
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Abstract

The invention discloses a grounding fault detection apparatus. The grounding fault detection apparatus comprises a signal generating device, a signal acquisition device and a signal receiving device. According to the grounding fault detection apparatus of the invention, the signal generating device is adopted, so that detection signals can be transmitted to a fault line; the signal acquisition device is adopted, so that the detection signals can be acquired from the fault line, and therefore, a fault point can be determined; and the signal receiving device is adopted, so that the position information of the fault point can be emitted out; and therefore, the fault point can be accurately positioned.

Description

A kind of ground-fault detection arrangement
Technical field
The present invention relates to a kind of power equipment, relate to a kind of ground-fault detection arrangement in particular.
Background technology
In recent years, along with the enforcement of electric network reconstruction engineering, the change of 10kV distribution line power supply mode, enhances the dielectric level of distribution line, reduces the trip-out rate of distribution line, improves power supply reliability, decrease line loss.But take new power supply mode in actual motion, frequent generation singlephase earth fault, particularly under the inclement weather conditions such as strong wind, heavy rain, hail, snow, earth fault frequently occurs, and has had a strong impact on the safety of converting equipment and power distribution network, economical operation.After fault occurs, because line length scope is wide, adopt by rule of thumb, segmentation is push-and-pull piecemeal in the past, and the classic method such as shaft tower inspection is investigated step by step, and waste time and energy, power failure range is large, and the time is long, very difficultly quick and precisely finds trouble spot.
Summary of the invention
For the deficiency that prior art exists, the object of the present invention is to provide a kind of ground-fault detection arrangement quick and precisely can finding trouble spot.
For achieving the above object, the invention provides following technical scheme: a kind of ground-fault detection arrangement, comprise signal generation apparatus, signal picker and Signal reception steady arm, described signal generation apparatus comprises timing chip, this chip has discharge end and output terminal, described discharge end is coupled with rheostat, described rheostatic one end is coupled to power supply after being coupled with the 7th resistance, the other end couples ground connection after the first electric capacity, this timing chip also has low triggering end and high-triggering end and control voltage end, described low triggering end and high-triggering end are all coupled between rheostat and the first electric capacity, diode is coupled with between described low triggering end and discharge end, described control voltage end is coupled with ground connection after the second electric capacity, described output terminal is coupled with ground connection after light emitting diode, also be coupled with the first operational amplifier, the in-phase input end of this first operational amplifier and the output terminal of timing chip couple, inverting input is coupled with ground connection after the second resistance, the second resistance is coupled to after the output terminal of described first operational amplifier is coupled with the first resistance, and be also coupled to faulty line, described signal picker comprises mutual inductor, second operational amplifier and the 3rd operational amplifier, described mutual inductor is hand-held mutual inductor, the out secondary of described mutual inductor and the in-phase input end of the second operational amplifier and inverting input couple, the inverting input of described second operational amplifier is also coupled with ground connection after the 4th resistance, the 4th resistance is coupled to after the output terminal of described second operational amplifier is coupled with the 3rd resistance, the inverting input of the 3rd operational amplifier is coupled to after being also coupled with the 5th resistance, the output terminal of this operational amplifier is coupled to after the inverting input of described 3rd operational amplifier is also coupled with the 6th resistance parallel with one another and the 3rd electric capacity, the in-phase input end ground connection of described 3rd operational amplifier, output terminal is coupled with zigbee module and the communication of Signal reception steady arm, described Signal reception steady arm comprises control CPU, liquid crystal display, 4G module, GPRS module and zigbee module, described control CPU and signal picker couple, described 4G module, liquid crystal display, GPRS module all couples with control CPU, when signal picker collects data and is input in control CPU time, control CPU shows this data by liquid crystal display, and obtain position location data by GPRS module, then by 4G module, position data is sent.
As a further improvement on the present invention, the rotating disc that described rheostat comprises base and is electrically connected with timing chip, one end of described base offers swivelling chute, described rotating disc is embedded in swivelling chute, described base supply the resistance of different resistance to embed embedding hole along the circumferential edge of swivelling chute along being placed with several, the cell wall of described swivelling chute offers and embedding hole through hole one to one, the circumferential edge of described rotating disc is provided with hemispherical contact, when needs resistance value, rotating disc is embedded in swivelling chute, hemispherical contact through one of them through hole and resistance in embedding hole corresponding to this through hole be electrically connected, one end of described rotating disc base dorsad is also coaxially fixed with column spinner, the side of described column spinner also offers anti-slip veins.
The present invention has following beneficial effect, when line fault, by the setting of signal generation apparatus, just can inject alien frequencies detection signal in faulty line, this alien frequencies detection signal will circulate in faulty line, at this moment signal picker is adopted to detect alien frequencies detection signal along faulty line again, real-time for the data detected is sent to Signal reception steady arm simultaneously, real-time for these data will show by Signal reception steady arm, in time certain some left and right sides being detected, there is this alien frequencies signal side, when opposite side does not have, then determine that this point is exactly fault ground point, now the position data of this point will detect by Signal reception steady arm, then control desk is sent, this makes it possible to promptly and accurately and effectively determine the trouble spot of circuit.
Accompanying drawing explanation
Fig. 1 is the circuit diagram of signal generation apparatus of the present invention;
Fig. 2 is the circuit diagram of signal picker of the present invention;
Fig. 3 is the module map of Signal reception steady arm of the present invention;
Fig. 4 is rheostatic one-piece construction figure in Fig. 1.
Embodiment
Shown in 4, a kind of ground-fault detection arrangement of the present embodiment, comprise signal generation apparatus 1, signal picker 2 and Signal reception steady arm 3, described signal generation apparatus 1 comprises timing chip U1, this chip has discharge end and output terminal, described discharge end is coupled with rheostat RP, power supply is coupled to after one end of described rheostat RP is coupled with the 7th resistance R7, the other end couples ground connection after the first electric capacity C1, this timing chip U1 also has low triggering end and high-triggering end and control voltage end, described low triggering end and high-triggering end are all coupled between rheostat RP and the first electric capacity C1, diode D is coupled with between described low triggering end and discharge end, described control voltage end is coupled with ground connection after the second electric capacity C2, described output terminal is coupled with ground connection after LED, also be coupled with the first operational amplifier Q1, the in-phase input end of this first operational amplifier Q1 and the output terminal of timing chip U1 couple, inverting input is coupled with ground connection after the second resistance R2, the second resistance R2 is coupled to after the output terminal of described first operational amplifier Q1 is coupled with the first resistance (R1), and be also coupled to faulty line, described signal picker 2 comprises mutual inductor L, second operational amplifier Q2 and the 3rd operational amplifier Q3, described mutual inductor L is hand-held mutual inductor, the out secondary of described mutual inductor L and the in-phase input end of the second operational amplifier Q2 and inverting input couple, the inverting input of described second operational amplifier Q2 is also coupled with ground connection after the 4th resistance R4, the 4th resistance R4 is coupled to after the output terminal of described second operational amplifier Q2 is coupled with the 3rd resistance R3, the inverting input of the 3rd operational amplifier Q3 is coupled to after being also coupled with the 5th resistance R5, the output terminal of this operational amplifier is coupled to after the inverting input of described 3rd operational amplifier Q3 is also coupled with the 6th resistance R6 parallel with one another and the 3rd electric capacity C3, the in-phase input end ground connection of described 3rd operational amplifier Q3, output terminal is coupled with zigbee module and Signal reception steady arm 3 communication, described Signal reception steady arm 3 comprises control CPU, liquid crystal display, 4G module, GPRS module and zigbee module, described control CPU and signal picker 2 couple, described 4G module, liquid crystal display, GPRS module all couples with control CPU, when signal picker 2 collects data and is input in control CPU time, control CPU shows this data by liquid crystal display, and obtain position location data by GPRS module, then by 4G module, position data is sent, when signal generation apparatus 1 works, its internal circuit will be connected, at this moment power supply will charge to the first electric capacity C1 by the 7th resistance R7 and rheostat RP, the discharge end of timing chip U1 is closed simultaneously, output terminal exports high level, because under the effect of charging, the terminal voltage of the first electric capacity C1 will constantly raise, and this terminal voltage can constantly be input in low triggering end and high-triggering end, when the terminal voltage of the first electric capacity C1 rises to the trigger voltage of high-triggering end time, timing chip U1 will action, discharge end is opened, output terminal changes output low level into simultaneously, so now the first electric capacity C1 will be discharged to discharge end by rheostat RP, so the terminal voltage of the first electric capacity C1 will decline slowly, when terminal voltage drops to low triggering end time, timing chip U1 will action, discharge end is closed, output terminal changes output high level again into simultaneously, the terminal voltage of the first electric capacity C1 continues to rise, in time rising to high-triggering end, timing chip U1 again can action, repeat above-mentioned action, export and can become low level more again, the output terminal of such timing chip U1 will export a square wave, and this wave frequency can by the resistance of standardsizing rheostat RP, and then regulate the discharge and recharge time of the first electric capacity C1 to realize, so just effectively achieve the effect that a signal occurs, the frequency adopted in the present embodiment is low frequency, and by the setting of LED, people just can be allowed to know, and the signal of signal generation apparatus 1 exports situation, people can be adjusted it timely and effectively, at signal generation apparatus 1 by alien frequencies signal injection to faulty line, people just can hold signal picker 2 and detect along faulty line one tunnel, in the process detected, mutual inductor L is only needed to press close to faulty line, because in time having Injection Signal to flow through in faulty line, will around faulty line formation magnetic field, such mutual inductor L just effectively can induce electric current, after mutual inductor L induces electric current, just can effectively be amplified the electric current that mutual inductor L induces by the second operational amplifier Q2, simultaneously due to the present embodiment employing is low frequency signal, thus the 3rd operational amplifier Q3 is adopted to form a low-pass filter here, so just effectively can ensure that the signal be transferred in Signal reception steady arm 3 is Injection Signal, instead of other undesired signals, make the location of trouble spot more accurate, and pass through the setting of zigbee module, just effectively can realize the wireless telecommunications between Signal reception steady arm 3, one is not easy the interference being subject to faulty line, two detect process in generic failure circuit can be higher, can inconvenience very if adopt the mode of wire to connect, after signals collecting arrives by signal picker 2, by zigbee module, signal will be sent to Signal reception steady arm 3, the zigbee module of Signal reception steady arm 3 inside will receive these signals, in appearance while alien frequencies signal can be measured, time another side can not measure, at this moment just represent and be positioned at the trouble spot on faulty line, thus at this time GPRS module will obtain the position data of this trouble spot, then sent by 4G module, , so just can effectively learn the position data of the trouble spot of faulty line, compared to the method adopting the mode of experience to carry out failure judgement point in prior art, many fast and accurately.
As a kind of embodiment improved, the rotating disc 5 that described rheostat RP comprises base 4 and is electrically connected with timing chip U1, one end of described base 4 offers swivelling chute 41, described rotating disc 5 is embedded in swivelling chute 41, described base 4 supply the resistance of different resistance to embed embedding hole 411 along the circumferential edge of swivelling chute 41 along being placed with several, the cell wall of described swivelling chute 41 offers and embedding hole 411 through hole 412 one to one, the circumferential edge of described rotating disc 5 is provided with hemispherical contact 51, when needs resistance value, rotating disc 5 is embedded in swivelling chute 41, the resistance of hemispherical contact 51 through one of them through hole 412 and in embedding hole 411 corresponding to this through hole 412 is electrically connected, one end of described rotating disc 5 base 4 dorsad is also coaxially fixed with column spinner 52, the side of described column spinner 52 also offers anti-slip veins, when the output frequency needing change signal generation apparatus 1, when namely changing the access resistance of rheostat RP, only need to catch column spinner 52 with hand, then column spinner 52 is turned, column spinner 52 driven rotary dish 5 is rotated in swivelling chute 41, while rotation, hemispherical contact 51 also can along with rotating together, in the process that hemispherical contact 51 rotates, will be embedded in through hole 412 one by one, when hemispherical contact 51 is embedded in a through hole 412 time, will contact by the resistance in embedding hole 411 corresponding to this through hole 412, at this moment the resistance in place in circuit is just the resistance of this resistance, when hemispherical contact 51 is embedded in another through hole 412 time, will Ohmic contact in the embedding hole 411 corresponding with this through hole 412, at this moment the resistance in place in circuit is just the resistance of this resistance, so just can be good at the effect playing a conversion resistance, and the resistance of conversion is fixing resistance, what thus would not occur adopting conventional rheostat to occur cannot by the problem of resistance conversion to a suitable resistance.
In sum, ground-fault detection arrangement of the present invention, by the setting of signal generation apparatus 1, just can inject alien frequencies detection signal in faulty line, by signal picker 2, alien frequencies detection signal is effectively detected, and by Signal reception steady arm 3 when signal picker 2 learns trouble spot, effectively the position data of trouble spot is sent out, play positioning action accurately and effectively, this makes it possible to the trouble spot of locating bad lines fast and accurately, compared to the mode of existing employing artificial experience, many quickly and accurately.
The above is only the preferred embodiment of the present invention, protection scope of the present invention be not only confined to above-described embodiment, and all technical schemes belonged under thinking of the present invention all belong to protection scope of the present invention.It should be pointed out that for those skilled in the art, some improvements and modifications without departing from the principles of the present invention, these improvements and modifications also should be considered as protection scope of the present invention.

Claims (2)

1. a ground-fault detection arrangement, it is characterized in that: comprise signal generation apparatus (1), signal picker (2) and Signal reception steady arm (3), described signal generation apparatus (1) comprises timing chip (U1), this chip has discharge end and output terminal, described discharge end is coupled with rheostat (RP), power supply is coupled to after one end of described rheostat (RP) is coupled with the 7th resistance (R7), the other end couples the first electric capacity (C1) ground connection afterwards, this timing chip (U1) also has low triggering end and high-triggering end and control voltage end, described low triggering end and high-triggering end are all coupled between rheostat (RP) and the first electric capacity (C1), diode (D) is coupled with between described low triggering end and discharge end, described control voltage end is coupled with the second electric capacity (C2) ground connection afterwards, described output terminal is coupled with light emitting diode (LED) ground connection afterwards, also be coupled with the first operational amplifier (Q1), the in-phase input end of this first operational amplifier (Q1) and the output terminal of timing chip (U1) couple, inverting input is coupled with the second resistance (R2) ground connection afterwards, the second resistance (R2) is coupled to after the output terminal of described first operational amplifier (Q1) is coupled with the first resistance (R1), and be also coupled to faulty line, described signal picker (2) comprises mutual inductor (L), second operational amplifier (Q2) and the 3rd operational amplifier (Q3), described mutual inductor (L) is hand-held mutual inductor, the out secondary of described mutual inductor (L) and the in-phase input end of the second operational amplifier (Q2) and inverting input couple, the inverting input of described second operational amplifier (Q2) is also coupled with the 4th resistance (R4) ground connection afterwards, the 4th resistance (R4) is coupled to after the output terminal of described second operational amplifier (Q2) is coupled with the 3rd resistance (R3), the inverting input of the 3rd operational amplifier (Q3) is coupled to after being also coupled with the 5th resistance (R5), the output terminal of this operational amplifier is coupled to after the inverting input of described 3rd operational amplifier (Q3) is also coupled with the 6th resistance (R6) parallel with one another and the 3rd electric capacity (C3), the in-phase input end ground connection of described 3rd operational amplifier (Q3), output terminal is coupled with zigbee module and Signal reception steady arm (3) communication, described Signal reception steady arm (3) comprises control CPU, liquid crystal display, 4G module, GPRS module and zigbee module, described control CPU and signal picker (2) couple, described 4G module, liquid crystal display, GPRS module all couples with control CPU, when signal picker (2) collects data and is input in control CPU time, control CPU shows this data by liquid crystal display, and obtain position location data by GPRS module, then by 4G module, position data is sent.
2. ground-fault detection arrangement according to claim 1, it is characterized in that: the rotating disc (5) that described rheostat (RP) comprises base (4) and is electrically connected with timing chip (U1), one end of described base (4) offers swivelling chute (41), described rotating disc (5) is embedded in swivelling chute (41), described base (4) supply the resistance of different resistance to embed embedding hole (411) along the circumferential edge of swivelling chute (41) along being placed with several, the cell wall of described swivelling chute (41) offers and embedding hole (411) through hole (412) one to one, the circumferential edge of described rotating disc (5) is provided with hemispherical contact (51), when needs resistance value, rotating disc (5) is embedded in swivelling chute (41), the resistance of hemispherical contact (51) through one of them through hole (412) and in embedding hole (411) corresponding to this through hole (412) is electrically connected, one end of described rotating disc (5) base (4) dorsad is also coaxially fixed with column spinner (52), the side of described column spinner (52) also offers anti-slip veins.
CN201510805795.8A 2015-11-20 2015-11-20 A kind of ground-fault detection arrangement Active CN105259479B (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111693819A (en) * 2020-05-25 2020-09-22 北京旋极信息技术股份有限公司 Detection method and device
CN112763935A (en) * 2019-10-21 2021-05-07 瑞昱半导体股份有限公司 Test system, transmitter and receiver for performing multiple tests
CN113702869A (en) * 2021-09-16 2021-11-26 浙江日新电气有限公司 Single-phase earth fault management system and control method

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JPS59141075A (en) * 1983-01-17 1984-08-13 Mitsubishi Electric Corp Fault position detector for power transmission line
JPH06130116A (en) * 1992-10-20 1994-05-13 Matsushita Electric Ind Co Ltd Transmission line fault searching device
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CN202066934U (en) * 2011-05-09 2011-12-07 航天科工深圳(集团)有限公司 Single phase earth fault positioning system of transmission line
CN203812663U (en) * 2014-03-19 2014-09-03 冯绍勇 Variable resistor
CN205103363U (en) * 2015-11-20 2016-03-23 国家电网公司 Earth fault check out test set

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS59141075A (en) * 1983-01-17 1984-08-13 Mitsubishi Electric Corp Fault position detector for power transmission line
JPH06130116A (en) * 1992-10-20 1994-05-13 Matsushita Electric Ind Co Ltd Transmission line fault searching device
CN201464598U (en) * 2009-06-11 2010-05-12 程刚 Concealed cable fault detector
CN201527459U (en) * 2009-07-15 2010-07-14 覃锦衔 Tracker of grounding point of power overhead line
CN201673234U (en) * 2010-05-26 2010-12-15 西安兴汇电力科技有限公司 Distribution line single-phase earth fault inspection device
CN102184625A (en) * 2011-03-15 2011-09-14 辽宁省电力有限公司抚顺供电公司 Third generation (3G) communication network-based transmission line fault area positioning system
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CN205103363U (en) * 2015-11-20 2016-03-23 国家电网公司 Earth fault check out test set

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112763935A (en) * 2019-10-21 2021-05-07 瑞昱半导体股份有限公司 Test system, transmitter and receiver for performing multiple tests
CN111693819A (en) * 2020-05-25 2020-09-22 北京旋极信息技术股份有限公司 Detection method and device
CN113702869A (en) * 2021-09-16 2021-11-26 浙江日新电气有限公司 Single-phase earth fault management system and control method

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