CN204964678U - Online positioning system of high tension cable line fault - Google Patents
Online positioning system of high tension cable line fault Download PDFInfo
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- CN204964678U CN204964678U CN201520641676.9U CN201520641676U CN204964678U CN 204964678 U CN204964678 U CN 204964678U CN 201520641676 U CN201520641676 U CN 201520641676U CN 204964678 U CN204964678 U CN 204964678U
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y04—INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
- Y04S—SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
- Y04S10/00—Systems supporting electrical power generation, transmission or distribution
- Y04S10/50—Systems or methods supporting the power network operation or management, involving a certain degree of interaction with the load-side end user applications
- Y04S10/52—Outage or fault management, e.g. fault detection or location
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Abstract
The utility model provides an online positioning system of high tension cable line fault, two current signal modulation terminals are used for being connected to the both ends of treating the detection streamer and carry out electric current signal acquisition to the two circuital current signal modulations that to gather are two way light signals, and two the optical signal input ends of optical fiber transmission to optical path switching unit are connected to two rethreads, microprocessor control optical path switching unit connects the optic fibre switching with two and is connected to the measuring junction of fiber time delay caliber or two current signal demodulation terminals's input, the delay information that optic fibre carries out two connection optic fibre of delay assay acquisition are connected to two of inserting to the fiber time delay caliber to with delay message routing to microprocessor, two current signal demodulation terminals are the signal of telecommunication with the light signal demodulation of inputing, again with sending into microprocessor after the conversion of signal of telecommunication AD. This positioning system can avoid the fiber length difference to bring delay measurement and need not the cable interface and withdraw from the operation, has better market perspective.
Description
Technical field
The utility model relates to a kind of high-tension cable detection system, especially a kind of detection system for Voltage Cable Lines Construction On-line Fault location.
Background technology
At present, high-voltage cable insulating localization of fault technology mainly adopts the impulse method based on off-line test, when producing cable fault, first power-off, then untied from system by cable line, recycling pulse signal carries out cable fault localization, based on the parameter model of cable line, by scene, pulse signal is applied to cable, then travel-time and velograph calculate trouble spot distance in the cable by electric current and voltage travelling wave signal.There is obvious shortcoming in the method, after cable breaks down, needs cable interface is out of service, then fault measuring equipment is transported to scene, arranges measuring equipment and wiring, could start to measure.
In addition, based on the synchronous high-tension cable On-line Fault location of GPS, due to the poor synchronization of gps clock, be difficult to accurate location, and the location technology of clock synchronous based on Optical Fiber Transmission, require consistent to two sensors module end fiber lengths of locating device, this makes troubles to Practical Project construction, add optical cable cost, the layout for locating device brings restriction simultaneously.
Summary of the invention
The technical problems to be solved in the utility model is: the problem that in prior art, the location of causing is inaccurate because the length difference of connecting fiber brings delay variation, and needs cable interface out of service, can not on-line checkingi.
In order to solve the problems of the technologies described above, the utility model provides a kind of Voltage Cable Lines Construction On-line Fault positioning system, comprises two current signal modulation terminals, two current signal demodulation terminals, two connecting fibers, optical path switch module, optical-fiber time-delay measuring appliance, alarm and microprocessors; Two current signal modulation terminals carry out current signal collection for the two ends being connected to cable to be detected, and be two ways of optical signals by the two-way current signal modulation collected, then transfer to two optical signal input of optical path switch module by two connecting fibers; Two connecting fibers switchings are connected to the measuring junction of optical-fiber time-delay measuring appliance or the input end of two current signal demodulation terminals by Microprocessor S3C44B0X optical path switch module; The two piece connecting fibers of optical-fiber time-delay measuring appliance to access carry out the Delay that time-delay analysis obtains two connecting fibers, and Delay is sent to microprocessor; The optical signal demodulation of input is electric signal by two current signal demodulation terminals, then sends after electric signal AD conversion into microprocessor; Alarm is connected with microprocessor.
Adopt current signal modulation terminal can real-time online sensed current signal, and without the need to cable interface is out of service, real-time and the detection efficiency of cable detection can be improved; Adopt optical path switch module can send into optical-fiber time-delay measuring appliance or current signal demodulation terminal according to detecting the light signal needing current signal modulation terminal to send, thus make time delay detection and fault detect share connecting fiber, save system cost; Adopt optical-fiber time-delay measuring appliance can detect the signal time delay caused by connecting fiber as required, thus effectively improve the precision of localization of fault; Adopt alarm can notify that when breaking down monitor staff investigates in time.
As further restriction scheme of the present utility model, current signal modulation terminal comprises current sensor and electrical to optical converter; Current sensor is used for gathering the current signal of cable under test, and the current signal collected is sent to electrical to optical converter; Current signal is converted to light signal by electrical to optical converter, and transfers to the optical signal input of optical path switch module by connecting fiber.Adopt current sensor can detect current signal on tested high-tension cable and fault traveling wave by real-time online, and be non-contact measurement, security performance is higher.
As further restriction scheme of the present utility model, current signal demodulation terminal comprises photoelectric commutator and AD converter; The light signal that optical path switch module exports is converted to electric signal by photoelectric commutator, and sends into microprocessor after carrying out AD conversion by AD converter.
As further improvement of the utility model scheme, current signal demodulation terminal also comprises a signal conditioning circuit be connected between photoelectric commutator and AD converter; The electric signal that photoelectric commutator exports is adjusted to the working range being adapted to AD converter by signal conditioning circuit.Adopt signal conditioning circuit the electric signal that photoelectric commutator exports can be adjusted to the working range being adapted to AD converter, improve the reliability that positioning system detects.
As further restriction scheme of the present utility model, optical-fiber time-delay measuring appliance is optical time domain reflectometer.
As further restriction scheme of the present utility model, optical path switch module is made up of the first controlled 1 × 2 photoswitch, the second controlled 1 × 2 photoswitch and the 3rd controlled 1 × 2 photoswitch; 1 port of the first controlled 1 × 2 photoswitch and the second controlled 1 × 2 photoswitch is connected to the output terminal of two current signal modulation terminals respectively by two connecting fibers, all have Single port to be connected to the input end of corresponding current signal demodulation terminal in 2 ports of the first controlled 1 × 2 photoswitch and the second controllable light 1 × 2 switch; 2 ports of the 3rd controlled 1 × 2 photoswitch are connected to the another port in 2 ports of the first controlled 1 × 2 photoswitch and the second controllable light 1 × 2 switch respectively, and 1 port of the 3rd controlled 1 × 2 photoswitch is connected to the measuring junction of optical-fiber time-delay measuring appliance.Adopt three controlled 1 × 2 photoswitches can realize the controlled switching of light path, and utilize the 3rd controlled 1 × 2 photoswitch that the two-way optical fiber of input is switched to optical-fiber time-delay measuring appliance successively, the optical-fiber time-delay measuring appliance using expensive multi input end can be avoided, effectively reduce system cost.
As further improvement of the utility model scheme, also comprise a display screen be connected with microprocessor.Utilize display screen can show abort situation in real time.
The beneficial effects of the utility model are: (1) adopts current signal modulation terminal can real-time online sensed current signal, and without the need to cable interface is out of service, can improve real-time and the detection efficiency of cable detection; (2) optical path switch module is adopted can to need first by the time delay of optical fiber latency measurement device measurement two-way optical fiber according to detecting, the demodulation of current signal is carried out afterwards by electric current signal receiving terminal, thus make time delay detection and fault detect share connecting fiber, save system cost; (3) adopt optical-fiber time-delay measuring appliance can detect the signal time delay caused by connecting fiber as required, thus effectively improve the precision of localization of fault; (4) alarm is adopted can to notify that when breaking down monitor staff investigates in time.
Accompanying drawing explanation
Fig. 1 is electrical block diagram of the present utility model;
Fig. 2 is the structural representation of optical path switch module of the present utility model;
Fig. 3 is that the utility model detects the fault traveling wave schematic diagram obtained.
Embodiment
As shown in Figure 1, the Voltage Cable Lines Construction On-line Fault positioning system that the utility model provides comprises: two current signal modulation terminals, two current signal demodulation terminals, two connecting fibers, optical path switch module, optical-fiber time-delay measuring appliance, display screen, alarm and microprocessors.
Wherein, two current signal modulation terminals carry out current signal collection for the two ends being connected to cable to be detected, and be two ways of optical signals by the two-way current signal modulation collected, then transfer to two optical signal input of optical path switch module by two connecting fibers; Two connecting fibers are switched the input end that the measuring junction that is connected to optical-fiber time-delay measuring appliance or switching are connected to two current signal demodulation terminals by Microprocessor S3C44B0X optical path switch module successively; The two piece connecting fibers of optical-fiber time-delay measuring appliance to access carry out the Delay that time-delay analysis obtains two connecting fibers, and Delay is sent to microprocessor; And the optical signal demodulation of input is electric signal by latter two current signal demodulation terminal, then send after electric signal AD conversion into microprocessor; Microprocessor carries out analytical calculation according to the delayed data of input and the electric signal of AD conversion, obtains fault location information; Display screen is all connected with microprocessor with alarm, and display screen is for showing abort situation, and alarm is used for reporting to the police when fault being detected, thus reminds monitor staff to carry out malfunction elimination rapidly.
Current signal modulation terminal generally comprises current sensor and electrical to optical converter; Current sensor is used for gathering the current signal of cable under test, and the current signal collected is sent to electrical to optical converter; Current signal is converted to light signal by electrical to optical converter, and transfers to the optical signal input of optical path switch module by connecting fiber.
Current signal demodulation terminal generally comprises photoelectric commutator, signal conditioning circuit and AD converter.The light signal that optical path switch module exports is converted to electric signal by photoelectric commutator, and sends into microprocessor after carrying out AD conversion by AD converter; Signal conditioning circuit is connected between photoelectric commutator and AD converter; The electric signal that photoelectric commutator exports is adjusted to the working range being adapted to AD converter by signal conditioning circuit.
This Voltage Cable Lines Construction On-line Fault positioning system operationally, first utilize optical path switch module two connecting fibers to be switched and be connected to optical-fiber time-delay measuring appliance, measure by optical-fiber time-delay measuring appliance the Signal transmissions time delay T1 and T2 that two connecting fiber L1 and L2 cause separately respectively;
Two connecting fibers switchings are connected to two current signal demodulation terminals by recycling optical path switch module respectively, send into microprocessor after carrying out optical signal demodulation by current signal demodulation terminal and carry out fault analysis, obtain fault traveling wave and transfer to the duration t1 of microprocessor from high-tension cable on the left of trouble spot and connecting fiber L1 and transfer to the duration t2 of microprocessor from high-tension cable on the right side of trouble spot and connecting fiber L2;
Last basis following formulae discovery trouble spot apart from the distance of check point on the left of high-tension cable to be measured is:
X=（L-V×（t1－t2＋T2-T1））/2
In formula, L is the length of cable about high-tension cable to be measured between two check points, and V is failed row velocity of wave propagation.
As shown in Figure 2, optical path switch module is made up of the first controlled 1 × 2 photoswitch, the second controlled 1 × 2 photoswitch and the 3rd controlled 1 × 2 photoswitch; 1 port of the first controlled 1 × 2 photoswitch and the second controlled 1 × 2 photoswitch is connected to the output terminal of two current signal modulation terminals respectively by two connecting fibers, all have Single port to be connected to the input end of corresponding current signal demodulation terminal in 2 ports of the first controlled 1 × 2 photoswitch and the second controllable light 1 × 2 switch; 2 ports of the 3rd controlled 1 × 2 photoswitch are connected to the another port in 2 ports of the first controlled 1 × 2 photoswitch and the second controllable light 1 × 2 switch respectively, and 1 port of the 3rd controlled 1 × 2 photoswitch is connected to the measuring junction of optical-fiber time-delay measuring appliance.
As shown in figs. 1 and 3, before localizing faults is measured, first controlled 1 × 2 photoswitch of Microprocessor S3C44B0X optical path switch module, the second controlled 1 × 2 photoswitch and the 3rd controlled 1 × 2 photoswitch, two connecting fibers are switched successively and is connected to fiber delay time measuring appliance, thus the time delay that two connecting fiber L1 and L2 cause is measured, obtaining time delay value is respectively T1 and T2, and by fiber delay time measuring appliance, T1 and T2 is sent to microprocessor and carries out stored record; And then control optical path switch module by two ways of optical signals switch input to two current signal modulation terminals respectively.After latency measurement, Microprocessor S3C44B0X optical path switch module, switches to fault traveling wave signal monitoring state by light path.
When cable to be detected breaks down, there will be the fault traveling wave shown in Fig. 3.Now the fault traveling wave signal treated on detection streamer is carried out Real-time Collection by current sensor, and by electrical to optical converter, the fault traveling wave signal of collection is converted to light signal, and transfer to the first controlled 1 × 2 photoswitch of optical path switch module and 1 port optical signal input part of the second controlled 1 × 2 photoswitch by connecting fiber; Again by the first controlled 1 × 2 photoswitch and second controlled 1 × 2 photoswitch of Microprocessor S3C44B0X optical path switch module, the light signal of two connecting fiber L1 and L2 conveying is switched and inputs to photoelectric commutator, by photoelectric commutator, the light signal received is converted to electric signal; By signal conditioning circuit, the electric signal that photoelectric commutator exports is nursed one's health again, this electric signal is gathered completely by AD converter; Microprocessor processes the signal after AD conversion.Supposing that microprocessor obtains according to the signal analysis after AD conversion the duration that fault traveling wave transfers to microprocessor from the high-tension cable of trouble spot the right and left and two connecting fiber L1 and L2 is respectively t1 and t2, failed row velocity of wave propagation is V, the length of cable to be detected is L, calculates trouble spot C to the current signal modulation termination detection point distance in left side to be by microprocessor:
X=V×（t1-T1）(1)
Calculating trouble spot C to the current signal modulation termination detection point distance on right side is:
L-X=V×(t2-T2)(2)
Can obtain according to formula (1) and (2) again:
X=（L-V×（t1－t2＋T2-T1））/2（3）
Thus calculate the size of trouble spot C to the current signal modulation termination detection point distance X in left side, and shown in real time by display screen.
Claims (7)
1. a Voltage Cable Lines Construction On-line Fault positioning system, is characterized in that: comprise two current signal modulation terminals, two current signal demodulation terminals, two connecting fibers, optical path switch module, optical-fiber time-delay measuring appliance, alarm and microprocessors; Two current signal modulation terminals carry out current signal collection for the two ends being connected to cable to be detected, and be two ways of optical signals by the two-way current signal modulation collected, then transfer to two optical signal input of optical path switch module by two connecting fibers; Two connecting fibers switchings are connected to the measuring junction of optical-fiber time-delay measuring appliance or the input end of two current signal demodulation terminals by Microprocessor S3C44B0X optical path switch module; The two piece connecting fibers of optical-fiber time-delay measuring appliance to access carry out the Delay that time-delay analysis obtains two connecting fibers, and Delay is sent to microprocessor; The optical signal demodulation of input is electric signal by two current signal demodulation terminals, then sends after electric signal AD conversion into microprocessor; Alarm is connected with microprocessor.
2. Voltage Cable Lines Construction On-line Fault positioning system according to claim 1, is characterized in that: current signal modulation terminal comprises current sensor and electrical to optical converter; Current sensor is used for gathering the current signal of cable under test, and the current signal collected is sent to electrical to optical converter; Current signal is converted to light signal by electrical to optical converter, and transfers to the optical signal input of optical path switch module by connecting fiber.
3. Voltage Cable Lines Construction On-line Fault positioning system according to claim 1 and 2, is characterized in that: current signal demodulation terminal comprises photoelectric commutator and AD converter; The light signal that optical path switch module exports is converted to electric signal by photoelectric commutator, and sends into microprocessor after carrying out AD conversion by AD converter.
4. Voltage Cable Lines Construction On-line Fault positioning system according to claim 3, is characterized in that: current signal demodulation terminal also comprises a signal conditioning circuit be connected between photoelectric commutator and AD converter; The electric signal that photoelectric commutator exports is adjusted to the working range being adapted to AD converter by signal conditioning circuit.
5. Voltage Cable Lines Construction On-line Fault positioning system according to claim 1 and 2, is characterized in that: optical-fiber time-delay measuring appliance is optical time domain reflectometer.
6. Voltage Cable Lines Construction On-line Fault positioning system according to claim 1, is characterized in that: optical path switch module is made up of the first controlled 1 × 2 photoswitch, the second controlled 1 × 2 photoswitch and the 3rd controlled 1 × 2 photoswitch; 1 port of the first controlled 1 × 2 photoswitch and the second controlled 1 × 2 photoswitch is connected to the output terminal of two current signal modulation terminals respectively by two connecting fibers, all have Single port to be connected to the input end of corresponding current signal demodulation terminal in 2 ports of the first controlled 1 × 2 photoswitch and the second controllable light 1 × 2 switch; 2 ports of the 3rd controlled 1 × 2 photoswitch are connected to the another port in 2 ports of the first controlled 1 × 2 photoswitch and the second controllable light 1 × 2 switch respectively, and 1 port of the 3rd controlled 1 × 2 photoswitch is connected to the measuring junction of optical-fiber time-delay measuring appliance.
7. Voltage Cable Lines Construction On-line Fault positioning system according to claim 1, is characterized in that: also comprise a display screen be connected with microprocessor.
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| CN201520641676.9U CN204964678U (en) | 2015-08-24 | 2015-08-24 | Online positioning system of high tension cable line fault |
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| CN201520641676.9U CN204964678U (en) | 2015-08-24 | 2015-08-24 | Online positioning system of high tension cable line fault |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108535603A (en) * | 2018-05-23 | 2018-09-14 | 安徽国电京润电力科技有限公司 | A kind of power circuit automatic fault detection positioning system |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108535603A (en) * | 2018-05-23 | 2018-09-14 | 安徽国电京润电力科技有限公司 | A kind of power circuit automatic fault detection positioning system |
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Inventor after: Chen Defeng Inventor after: Zhang Chengxian Inventor after: Wang Yongqiang Inventor after: Gao Shengyu Inventor after: Liu Xiaodong Inventor after: Gu Chengyang Inventor after: Li Hongze Inventor after: Wang Chunning Inventor after: Zhang Tao Inventor after: Pan Rong Inventor after: Lu Yi Inventor before: Gao Shengyu Inventor before: Pan Rong Inventor before: Lu Yi Inventor before: Qian Hongwei Inventor before: Zhang Chengxian Inventor before: Chen Defeng Inventor before: Liu Xiaodong Inventor before: Gu Chengyang Inventor before: Li Hongze Inventor before: Wang Guangming Inventor before: Wang Chunning Inventor before: Zhang Tao Inventor before: Xue Hengsong |
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