CN211718433U - Optical measurement device suitable for positioning lightning stroke fault of power transmission line - Google Patents

Abstract

The utility model discloses an optical measurement device suitable for location transmission line thunderbolt trouble, include the compound overhead earth wire of optic fibre parallel with transmission line, still include: the double-pulse laser generator, the micro optical isolator, the optical fiber coupling acousto-optic modulator, the optical amplifier, the optical polarization controller, the optical fiber circulator and the OPGW optical fiber are sequentially and continuously connected with the signal output end and the input end; and the signal output end and the input end are sequentially and continuously connected with the micro optical isolator, the balanced photoelectric amplification detector, the band-pass filter, the low-noise amplifier and the detection signal processor. The device utilizes the structure of OPGW and based on the Rayleigh scattering principle to establish an optical measuring instrument suitable for positioning the lightning stroke fault of the power transmission line, and realizes accurate lightning stroke point positioning through data processing, thereby providing a comprehensive management platform for comprehensively popularizing lean management of a provincial network level state monitoring and evaluating center and improving the safety and stability of equipment operation.

Description

Optical measurement device suitable for positioning lightning stroke fault of power transmission line

Technical Field

The utility model relates to a power equipment state monitoring and fault diagnosis technique, especially through the monitoring system of optical technology to the transmission line state.

Background

The power transmission and transformation equipment state monitoring and diagnosis technology is a key link in a first defense system for preventing power grid accidents and is also a key link for implementing an intelligent power grid. The power transmission line has wide multiple surfaces and extremely large distribution area, and is very easy to cause tripping faults due to thunder and lightning. Statistical results show that lightning strike is the main cause of transmission line failure. The lightning stroke monitoring can be used for timely and accurately checking and judging lightning stroke fault points, is a premise for effectively clearing faults and reducing power failure loss, and is also a necessary means for lightning protection evaluation and lightning protection.

China began to build wide-area lightning location systems since the 80 s of the last century. The system can remotely measure electromagnetic field signals in a specific frequency band range radiated when lightning occurs, acquire parameters such as occurrence time, position, polarity and lightning current intensity of ground lightning strike each time, and perform statistical analysis on massive lightning parameters to realize monitoring of large-range ground lightning activity. However, due to the space-time randomness of natural lightning and the short duration of primary lightning, it is generally difficult to obtain effective observation data to test the accuracy of the lightning positioning result. The artificial simulated lightning stroke inspection result shows that the effective detection efficiency of the lightning positioning system on the main lightning main discharge can reach 94%, but the subsequent back strike detection efficiency is reduced to 60%; the average positioning error of the lightning positioning system to the two types of lightning stroke positions is about 700 meters and 500 meters; the relative error of the lightning positioning system to the measurement of the lightning current peak value is about 16.3% -19.1%. The effect of monitoring the visible lightning stroke needs to be further improved.

An optical fiber composite overhead ground wire (OPGW) is commonly used in a power transmission line to replace a conventional ground wire, and the OPGW has the functions of both a common ground wire and a communication optical cable. The OPGW is internally provided with the optical fiber, and when light is transmitted in the optical fiber, a small part of light deviates from the original transmission direction due to electromagnetic pulses formed in the lightning stroke process, so that scattering and reflection are generated. This property is attributed to rayleigh scattering.

Disclosure of Invention

The utility model aims at providing a device is surveyed to optics suitable for fix a position transmission line thunderbolt trouble.

In order to achieve the above purpose, the technical scheme of the utility model is as follows:

the utility model provides an optical measurement device suitable for location transmission line thunderbolt trouble, includes the compound overhead earth wire of optic fibre parallel with transmission line, its characterized in that still includes:

the double-pulse laser generator, the micro optical isolator, the optical fiber coupling acousto-optic modulator, the optical amplifier, the optical polarization controller, the optical fiber circulator and the OPGW optical fiber are sequentially and continuously connected with the signal output end and the input end; and

the micro optical isolator, the balanced photoelectric amplification detector, the band-pass filter, the low-noise amplifier and the detection signal processor are sequentially connected with the signal output end and the signal input end;

wherein, the signal output ends of the micro optical isolator and the optical fiber circulator are also respectively connected with the signal input end of the micro optical isolator.

The double-pulse laser generator can simultaneously emit two paths of optical signals, the output power of the double-pulse laser generator is greater than 10 watts, and the pulse width of the double-pulse laser generator is less than 0.25 second.

The micro optical isolator can realize the one-way transmission of optical signals, the insertion loss of the micro optical isolator is less than 0.5dB, and the isolation degree of the micro optical isolator is greater than 60 dB.

The optical fiber coupling acousto-optic modulator can control the intensity and time of an optical signal, the insertion loss of the optical fiber coupling acousto-optic modulator is less than 1dB, and the extinction ratio of the optical fiber coupling acousto-optic modulator is greater than 50 dB.

The optical amplifier adopts an erbium-doped fiber amplifier, and the relay distance of optical signal transmission after amplification reaches more than 100 kilometers.

The optical polarization controller can limit the polarization state of an optical signal, and the insertion loss of the optical polarization controller is less than 1dB and the polarization loss of the optical polarization controller is less than 0.15 dB.

The optical fiber circulator is made of ferrite gyromagnetic materials, the insertion loss of the optical fiber circulator is less than 0.5dB, the polarization loss of the optical fiber circulator is less than 0.1dB, and the number of ports is more than 3.

And the OPGW optical fiber adopts a redundant optical fiber in the composite overhead ground wire.

The micro optical isolator can realize the one-way transmission of optical signals, the insertion loss of the micro optical isolator is less than 0.5dB, and the isolation degree of the micro optical isolator is greater than 60 dB.

The balanced photoelectric amplification detector can convert the radiation energy of optical signals into electric signals, the detection wavelength of the balanced photoelectric amplification detector reaches 150-1600 nanometers, and the common-mode rejection ratio is larger than 30 dB.

The band-pass filter can suppress interference and noise outside the center frequency.

The low-noise amplifier is made of a CMOS device with a cascode structure, and the gain of the low-noise amplifier reaches 17 dB.

The detection signal processor is made of a field programmable gate array-based application-specific integrated circuit.

The optical measurement device for positioning the lightning stroke fault of the power transmission line with the structure utilizes the structure of the OPGW and the Rayleigh scattering principle to establish the optical measurement device suitable for positioning the lightning stroke fault of the power transmission line, and realizes accurate lightning stroke point positioning through data processing, thereby providing a comprehensive management platform for comprehensively popularizing lean management of a provincial network level state monitoring and evaluating center and improving the safety and stability of equipment operation.

The utility model discloses creatively through deploying optical measurement device monitoring transmission line in the transformer substation and suffering the position and the intensity that transmission line struck by lightning, successfully break away from the heavy drawback of open-air monitor terminal maintenance task, show the maintenance efficiency that has promoted monitoring system.

Drawings

Fig. 1 is a schematic structural diagram of the present invention;

in the figure, a double-pulse laser generator 1, a micro optical isolator 2, an optical fiber coupling acousto-optic modulator 3, an optical polarization controller 4, an optical amplifier 5, an optical fiber circulator 6, an OPGW optical fiber 7, a micro optical isolator 8, a balanced photoelectric amplification detector 9, a band-pass filter 10, a low-noise amplifier 11 and a detection signal processor 12 are arranged.

Detailed Description

For better understanding of the present invention, the following description of the present invention is made with reference to the accompanying drawings.

Fig. 1 is a schematic structural diagram of the present invention, and it can be known from the figure that it includes a built-in optical fiber of the optical fiber composite overhead ground wire, i.e. an OPGW optical fiber 7, and further includes a dual pulse laser generator 1, a micro optical isolator 2, an optical fiber coupling acousto-optic modulator 3, an optical amplifier 4, an optical polarization controller 5, an optical fiber circulator 6 OPGW optical fiber 7, and a micro optical isolator 8, a balanced photoelectric amplification optical isolator detector 9, a band pass filter 10, a low noise amplifier 11, and a detection signal processor 12, where the signal output end and the input end are sequentially connected; wherein, the signal output ends of the micro optical isolator 2 and the optical fiber circulator 6 are also respectively connected with the signal input end of the micro optical isolator 8.

The double-pulse laser generator 1 can simultaneously emit two paths of optical signals, the output power of the double-pulse laser generator is more than 10 watts, and the pulse width of the double-pulse laser generator is less than 0.25 second.

The micro optical isolator 2 can realize the one-way transmission of optical signals, the insertion loss of the micro optical isolator is less than 0.5dB, and the isolation degree of the micro optical isolator is greater than 60 dB.

The optical fiber coupling acousto-optic modulator 3 can control the intensity and time of an optical signal, the insertion loss of the optical fiber coupling acousto-optic modulator is less than 1dB, and the extinction ratio of the optical fiber coupling acousto-optic modulator is more than 50 dB.

The optical amplifier 4 adopts an erbium-doped fiber amplifier, and the relay distance of the amplified optical signal transmission reaches more than 100 kilometers.

The optical polarization controller 5 may limit the polarization state of the optical signal with an insertion loss of less than 1dB and a polarization loss of less than 0.15 dB.

The optical fiber circulator 6 is made of ferrite gyromagnetic materials, the insertion loss of the optical fiber circulator is less than 0.5dB, the polarization loss of the optical fiber circulator is less than 0.1dB, and the number of ports is more than 3.

The OPGW optical fiber 7 adopts a redundant optical fiber in a composite overhead ground wire.

The micro optical isolator 8 can realize the one-way transmission of optical signals, the insertion loss of the micro optical isolator is less than 0.5dB, and the isolation degree of the micro optical isolator is greater than 60 dB.

The balanced photoelectric amplification detector 9 can convert the radiation energy of optical signals into electric signals, the detection wavelength reaches 150 to 1600 nanometers, and the common mode rejection ratio is greater than 30 dB.

The band-pass filter 10 can suppress interference and noise outside the center frequency.

The low noise amplifier 11 is made of a CMOS device with a cascode structure, and the gain of the low noise amplifier reaches 17 dB.

The detection signal processor is made of a field programmable gate array-based application-specific integrated circuit.

During operation, an optical signal emitted by the double-pulse laser generator 1 is divided into two paths of signals after passing through the micro optical isolator 2. One path of optical signal is firstly modulated into an optical pulse for monitoring a lightning stroke signal through an optical fiber coupling acousto-optic modulator 3, and a modulation wave of frequency shift information exceeding ten megahertz is loaded; secondly, the radiation is amplified by the stimulated radiation of the optical amplifier 4; then the polarization state of the pulse light signals at different moments is changed by the light polarization controller 5 so as to reduce the polarization noise during coherent detection; and finally transmitted to OPGW fiber 7 via fiber circulator 6. The other path of signal is a reference optical signal for realizing coherent detection on the premise of wave front matching with the coherent optical signal reflected by the OPGW optical fiber 7.

If lightning strikes on the optical fiber composite overhead ground wire, a Rayleigh scattering phenomenon is generated, and a small part of light is deviated from the original transmission direction due to the formed electromagnetic pulse, so that scattering and reflection are generated. When this optical signal generates a back-scattered optical signal in the OPGW fiber 7, it will be reflected to the fiber circulator 6 and transmitted to the micro-optical isolator 8. After the back scattering light signal is mixed with the reference light, the intermediate frequency signal generated by heterodyning the two signals is transmitted to the balanced photoelectric amplification detector 9. After the balanced photoelectric amplification detector 9 performs photoelectric conversion, transimpedance amplification conversion, and outputs an intermediate-frequency voltage signal, the obtained electric signal is sequentially transmitted to the band-pass filter 10, the low-noise amplifier 11, and the detection signal processor 12. At this time, the power of the intermediate frequency signal is demodulated by the detection signal processor, so that an optical fiber backscattering curve is obtained, and the lightning stroke position and amplitude are identified.

The present invention is not limited to the above-described embodiments, but only to the preferred embodiments of the present invention, and the present invention is not limited thereto, and any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention should be included within the protection scope of the present invention.

Claims (9)

1. The utility model provides an optical measurement device suitable for location transmission line thunderbolt trouble, includes the compound overhead earth wire of optic fibre parallel with transmission line, its characterized in that still includes:

the double-pulse laser generator, the micro optical isolator, the optical fiber coupling acousto-optic modulator, the optical amplifier, the optical polarization controller, the optical fiber circulator and the OPGW optical fiber are sequentially and continuously connected with the signal output end and the input end; and

the micro optical isolator, the balanced photoelectric amplification detector, the band-pass filter, the low-noise amplifier and the detection signal processor are sequentially connected with the signal output end and the signal input end;

wherein, the signal output ends of the micro optical isolator and the optical fiber circulator are also respectively connected with the signal input end of the micro optical isolator.

2. An optical measuring device according to claim 1, characterized in that:

the double-pulse laser generator can simultaneously emit two paths of optical signals, the output power of the double-pulse laser generator is greater than 10 watts, and the pulse width of the double-pulse laser generator is less than 0.25 second.

3. An optical measuring device according to claim 1, characterized in that:

the micro optical isolator can realize the one-way transmission of optical signals, the insertion loss of the micro optical isolator is less than 0.5dB, and the isolation degree of the micro optical isolator is greater than 60 dB.

4. An optical measuring device according to claim 1, characterized in that:

the optical fiber coupling acousto-optic modulator can control the intensity and time of an optical signal, the insertion loss of the optical fiber coupling acousto-optic modulator is less than 1dB, and the extinction ratio of the optical fiber coupling acousto-optic modulator is greater than 50 dB.

5. An optical measuring device according to claim 1, characterized in that:

the optical amplifier adopts an erbium-doped fiber amplifier, and the relay distance of optical signal transmission after amplification reaches more than 100 kilometers.

6. An optical measuring device according to claim 1, characterized in that:

the optical polarization controller can limit the polarization state of an optical signal, and the insertion loss of the optical polarization controller is less than 1dB and the polarization loss of the optical polarization controller is less than 0.15 dB.

7. An optical measuring device according to claim 1, characterized in that:

the optical fiber circulator is made of ferrite gyromagnetic materials, the insertion loss of the optical fiber circulator is less than 0.5dB, the polarization loss of the optical fiber circulator is less than 0.1dB, and the number of ports is more than 3.

8. An optical measuring device according to claim 1, characterized in that:

and the OPGW optical fiber adopts a redundant optical fiber in the composite overhead ground wire.

9. An optical measuring device according to claim 1, characterized in that:

the balanced photoelectric amplification detector can convert the radiation energy of optical signals into electric signals, the detection wavelength reaches 150-1600 nanometers, and the common-mode rejection ratio is greater than 30 dB;

the band-pass filter can suppress interference and noise outside the central frequency;

the low-noise amplifier is made of a CMOS device with a cascode structure, and the gain of the low-noise amplifier reaches 17 dB;

the detection signal processor is made of a field programmable gate array-based application-specific integrated circuit.

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