CN204359461U - A kind of electric aerial optical cable distributed on line monitoring device - Google Patents

Abstract

The utility model discloses a distributed on-line monitoring device for an electric overhead optical cable, which comprises a Brillouin optical time domain reflectometer, a guiding optical cable, an optical fiber splicing box, an electric overhead optical cable and an optical switching switch, and the Brillouin optical time domain reflectometer is useful An optical port for sending pulsed laser signals and receiving feedback Brillouin spectrum signals, the guiding optical cable includes a first guiding optical fiber and a second guiding optical fiber, the power overhead optical cable is provided with an optical unit, the optical unit includes a seamless tube and is arranged One tightly wrapped optical fiber and at least one bare fiber in the tube. Compared with the seamless tube, the tight wrapped optical fiber has no excess length, and the bare fiber has an excess length of 0.9-1.1%. The advantage is that by using the Brillouin optical time domain reflectometer, In this way, only one optical unit inside the power overhead optical cable can realize distributed real-time measurement of tens of kilometers of overhead line temperature and strain.

Description

A distributed on-line monitoring device for power overhead optical cable

technical field

The utility model relates to the field of overhead transmission line monitoring, in particular to a distributed on-line monitoring device for electric overhead optical cables.

Background technique

Power aerial optical cable is an important carrier of power system communication and dispatch. At present, power overhead optical cables mainly include dielectric self-supporting optical cable ADSS, optical fiber composite overhead ground wire OPGW and optical fiber composite overhead phase wire OPPC, especially OPGW and OPPC, which have dual functions of ground wire/phase wire and communication, and are obtained in power transmission lines. Wide range of applications. However, like ordinary overhead transmission lines, power overhead optical cables are widely distributed in the wild, and factors such as line aging, meteorological disasters, and external damage pose a huge threat to the safe and stable operation of the line. The traditional inspection of overhead transmission lines mainly relies on periodic inspections by operation and maintenance personnel, which has many limitations such as difficult to find fault points, poor real-time performance, and limited monitoring range, which can no longer meet the needs of today's smart grid construction. Therefore, advanced communication, sensing The integration and integration of technology and transmission technology, timely acquisition of information on the operation status of transmission lines, and improvement of the automation level of operation management are the development directions of the power industry.

The real-time temperature and strain measurement information and long-term operation history data of power overhead lines can reflect the health status of overhead lines, and timely detect local hot spots, icing, broken strands and other faults of overhead lines to ensure the safety of power transmission. The Chinese Utility Model Patent No. 201220385724.9 authorized by the announcement on February 27, 2013 "on-line comprehensive monitoring system for ultra-high voltage transmission lines" (authorization number CN202757987U) discloses an intelligent comprehensive monitoring system including a distributed optical fiber online temperature measurement system. The sensing optical cable of the optical fiber online temperature measurement system is embedded in the power cable, which can monitor the conductor temperature and the dynamic ampacity of the cable in real time. However, the distributed optical fiber online temperature measurement system in this patent can only use the sensing optical fiber to realize the measurement of the temperature of the transmission line. The patent "on-line monitoring device for temperature and strain fused with optical fiber composite phase line" (application number 201320019170.5) proposes an online temperature and strain monitoring device for fused optical fiber composite phase line. Temperature function, and then use the Brillouin fiber optic sensor to realize the strain measurement function, because the performance of the Raman device decreases sharply with the increase of distance, which limits the measurement distance, and this method uses two kinds of measurement devices to increase the system cost. The patent "Optical Fiber Composite Overhead Phase Line and System for Distributed Temperature and Strain Monitoring" (application number 201310182448.5) proposes a method for monitoring line temperature and strain by using the optical unit inside the optical fiber composite overhead phase line (OPPC). The OPPC needs to set two optical units of bare fiber and single-mode tight-wrapped fiber, which will increase the manufacturing cost, and the bare fiber and single-mode tight-wrapped fiber optical unit are located at the opposite position of the twisted layer. There are differences in the temperature of the unit. In addition, the single-mode tight-packed optical fiber used for strain monitoring is located in the stranding layer, and there is an excess stranding length, which cannot meet the strain monitoring when the tension of the overhead optical cable is small.

Contents of the invention

The technical problem to be solved by the utility model is to provide a distributed on-line monitoring device for electric overhead optical cables with relatively low manufacturing cost and which can meet various monitoring environments.

The technical scheme adopted by the utility model to solve the above-mentioned technical problems is: a distributed on-line monitoring device for electric overhead optical cables, including a Brillouin optical time domain reflectometer, a guiding optical cable, an optical fiber splicing box, an electric overhead optical cable and an optical switching switch. The Brillouin optical time domain reflectometer described above is provided with an optical port for sending a pulsed laser signal and receiving a fed back Brillouin spectrum signal, and the guiding optical cable includes a first guiding optical fiber and a second guiding optical fiber, and the optical fiber The switch is provided with an optical input port, a first optical output port and a second optical output port, the optical port is connected to the optical input port, the first optical output port is connected to the first guide fiber connected to the input end, the second optical output port is connected to the input end of the second guide fiber, the power aerial optical cable is provided with an optical unit, and the optical unit includes a seamless tube and is arranged on the A tightly wrapped optical fiber and at least one bare fiber in the seamless tube, the input end of the tight wrapped optical fiber is connected to the output end of the first guided optical fiber in the optical fiber splice box, the The input end of the bare fiber is connected to the output end of the second guide fiber in the fiber splice box. Compared with the seamless tube, the tight-wrapped fiber has no excess length, and the bare fiber The remaining fiber length is 0.9-1.1%.

The bare fiber in the seamless tube of the optical unit is helically arranged around the tightly wrapped optical fiber.

The optical unit is arranged at the center layer of the electric overhead optical cable.

In order to obtain a larger strain measurement range, the optical unit can also be arranged on the twisted layer of the electric aerial optical cable.

The guiding optical cable is an ordinary communication optical cable, and at least two guiding optical fibers are arranged in the guiding optical cable.

Compared with the prior art, the utility model has the advantage that by using the Brillouin optical time domain reflectometer, only one optical unit inside the power overhead optical cable can be used to realize the distributed real-time measurement of the temperature and strain of the overhead line without additional arrangement The sensor is simple in construction and does not affect the structure, stress distribution performance and manufacturing process of the power overhead optical cable. It is easy to implement and can realize distributed temperature and strain monitoring up to tens of kilometers. The Brillouin optical time domain reflectometer is a new type of equipment for real-time measurement of the Brillouin spectrum distribution of the optical fiber. The Brillouin spectrum is also sensitive to the temperature and strain of the optical fiber. Temperature or/and strain distribution information along the line. The Brillouin optical time domain reflectometer respectively receives the scattering signals of the tight-wrapped optical fiber and the bare fiber of the internal optical unit of the power overhead optical cable, and calculates the Brillouin spectrum distribution information of the tight-wrapped optical fiber and the bare fiber. At the same position of the overhead optical cable, the temperature of the tight-wrapped optical fiber and the bare fiber inside the optical unit is basically the same. Since the bare fiber is set with an excess length of more than 0.9%, even if the overhead optical cable is strained and stretched, it will not be affected. The bare fiber will be stressed, so the bare fiber in the optical unit is only related to the temperature of the overhead line, and has nothing to do with the strain; and because the tight-packed optical fiber inside the optical unit has no excess length, when there is strain in the power overhead optical cable and deformation occurs It will also affect the tight-packed optical fiber in the optical unit synchronously, so the temperature and strain of the tight-packed optical fiber in the unit and the overhead line are related at the same time. Combined with the Brillouin spectrum information of the bare fiber in the optical unit (only related to temperature), the strain-affected Brillouin spectrum information of the tightly wrapped optical fiber in the optical unit can be separated, so as to realize the temperature and strain distribution of the power overhead optical cable monitor. The use of optical fiber splicing boxes has the function of optical fiber splicing protection and can coil redundant optical fibers.

Since the allowable maximum tension of the design of the electric overhead optical cable is generally large, and the tension is relatively small during the normal installation of the overhead cable, if it is not necessary to monitor the stress state during the installation of the overhead cable, the optical unit can be set on the twisted side of the electric overhead optical cable. layer. At this time, because the optical unit is located in the twisted layer, there is a certain twisted excess length, thereby obtaining a larger strain measurement range.

Description of drawings

Fig. 1 is a structural schematic diagram of a distributed on-line monitoring device for electric overhead optical cables of the utility model;

Fig. 2 is a schematic structural view of the power overhead optical cable with the optical unit in the central layer of Embodiment 1 of the present utility model;

Fig. 3 is a schematic structural diagram of an electric aerial optical cable with an optical unit in a twisted layer according to Embodiment 2 of the present invention.

Detailed ways

The utility model is described in further detail below in conjunction with the accompanying drawings.

Embodiment 1: As shown in Figure 1, a distributed on-line monitoring device for power overhead optical cables based on Brillouin optical time domain reflectometer, including: Brillouin optical time domain reflectometer 1, guide optical cable 2, and optical fiber splicing box 3 , power overhead optical cable 4 and optical switch 5. As shown in Figure 2, the electric overhead optical cable 4 is an optical fiber composite overhead phase line OPPC, which has the functions of power transmission and electric communication, and includes an optical unit 41, an aluminum-clad steel wire 42 and an aluminum wire 43. 4, the optical unit 41 includes a seamless tube 410 and a tight-wrapped optical fiber 411 and six bare fibers 412 arranged in the seamless tube 410. Compared with the seamless tube 410, the tight-wrapped optical fiber 411 has no excess length, and the bare The excess length of fiber 412 is 0.9%; the Brillouin optical time domain reflectometer 1 has an optical port 11, which is used to send pulsed laser signals and receive feedback Brillouin spectrum signals, and the first guiding optical fiber 21 and the first guiding optical fiber 21 are arranged in the guiding optical cable 2 The second guide fiber 22, the optical switch 5 has an optical input port 51, a first optical output port 52 and a second optical output port 53, the optical port 11 is connected to the optical input port 51, and the first optical output port 52 is connected to the first optical output port 52. The input end of optical fiber 21 is connected, and the second optical output port 53 is connected with the input end of second guide optical fiber 22, and the input end of tight-packed optical fiber 411 is connected with the output end of first guide optical fiber 21 in optical fiber splicing box 3, and bare fiber The input end of 412 is connected to the output end of the second guiding fiber 22 in the fiber splicing box 3; the fiber splicing box 3 is a conventional outdoor type, which can protect the optical fiber fusion splicing point and coil and store redundant optical fibers.

Embodiment 2: The structure is similar to Embodiment 1, except that the optical unit 41 is arranged on the twisted layer of the electric aerial optical cable 4 , as shown in FIG. 3 . There are two bare fibers 412, and the excess length of the bare fibers 412 is 1.1%.

In the above embodiment, when measuring the temperature of the power overhead optical cable 4, the optical switch 5 is set to prohibit the optical input port 51 to the first optical output port 52, and the optical input port 51 to the first optical output port 53 to conduct. The light emitted by the deep-type optical time-domain reflectometer 1 is input into the bare fiber 412 through the optical switch 5 and the second guide fiber 22, and the Brillouin spectrum of the bare fiber 412 is obtained by measuring the Brillouin-type optical time-domain reflectometer 1. Because the excess length of the bare fiber 412 is relatively large, it is only related to the temperature of the electric overhead optical cable 4, that is, the Brillouin spectrum information of the bare fiber 412 only reflects the temperature information of the aerial optical cable 4; when measuring the strain of the electric overhead optical cable 4, the optical switching The switch 5 is set to conduct from the optical input port 51 to the first optical output port 52, and to prohibit the optical input port 51 to the second optical output port 53. At this time, the light emitted by the Brillouin optical time domain reflectometer 1 passes through the optical switch 5. The first guide optical fiber 21 is input into the tight-wrapped optical fiber 411, and the Brillouin spectrum of the bare fiber 411 is obtained by measuring the Brillouin optical time-domain reflectometer 1, while the tight-wrapped optical fiber 411 has no excess length, and the power overhead optical cable 4 The strain synchronously affects the strain of the tight-wrapped optical fiber 411 , so the temperature and strain of the tight-wrapped optical fiber 411 and the electric aerial optical cable 4 are related simultaneously. Combined with the Brillouin spectrum information of the bare fiber 411 (only related to temperature), the strain-affected Brillouin spectrum information of the tightly wrapped optical fiber 412 can be separated, so as to realize the distributed monitoring of the temperature and strain of the electric aerial optical cable 4 .

Claims (5)

1. A distributed on-line monitoring device for electric power overhead optical cable, characterized in that it comprises a Brillouin optical time domain reflectometer, a guide cable, an optical fiber splice box, an electric power overhead optical cable and an optical switch, and the described Brillouin optical time domain reflectometry The instrument is provided with an optical port for sending pulsed laser signals and receiving feedback Brillouin spectrum signals, the guide optical cable includes a first guide fiber and a second guide fiber, and the optical switch is provided with an optical input port, a second guide fiber An optical output port and a second optical output port, the optical port is connected to the optical input port, the first optical output port is connected to the input end of the first guiding fiber, and the second The two optical output ports are connected to the input end of the second guide fiber, and the power aerial optical cable is provided with an optical unit, and the optical unit includes a seamless tube and a tight tube arranged in the seamless tube wrapped fiber and at least one bare fiber, the input end of the tight-wrapped fiber is connected to the output end of the first guided fiber in the fiber splicing box, the input end of the bare fiber is connected to the The output end of the second guide fiber is connected in the optical fiber splicing box. Compared with the seamless tube, the tight-wrapped optical fiber has no excess length, and the bare fiber excess length is 0.9-1.1%. 2. A distributed on-line monitoring device for overhead optical cables according to claim 1, characterized in that the bare fibers in the seamless tube of the optical unit are helically arranged around the tightly wrapped optical fibers. 3. A distributed on-line monitoring device for overhead power optical cables according to claim 1, characterized in that said optical unit is arranged at the center layer of said overhead power optical cables. 4. A distributed on-line monitoring device for electric overhead optical cables according to claim 1, characterized in that said optical unit can also be arranged in the stranding layer of said electric overhead optical cables. 5. A distributed on-line monitoring device for overhead power cables according to claim 1, wherein said guide cables are ordinary communication cables, and said guide cables are provided with at least two guide fibers.