CN204373692U - A kind of electric aerial optical cable temperature and Strain Distribution formula monitoring device - Google Patents

Abstract

The utility model relates to a temperature and strain distributed monitoring device for an overhead optical cable of electric power, which comprises a test host, an overhead optical cable, and an optical fiber connection box. Two optical units are arranged in the overhead optical cable, wherein the first optical unit is located in the center of the optical cable. There is at least one tight-buffered fiber with no excess length, the second optical unit is located in the twisted layer of the optical cable, and at least one loose-buffered fiber with an excess length of 0.5-0.8%, one end of the tight-buffered fiber and the loose-buffered fiber are respectively connected to the test host The two optical ports are connected, and the other ends of the tight-buffered fiber and the loose-buffered fiber respectively enter the fiber splicing box and are connected. Tight-buffered optical fibers and loose-buffered optical fibers are used for distributed strain and temperature measurement respectively, so as to realize distributed real-time monitoring of power overhead lines and ensure the safety of power transmission.

Description

A Distributed Monitoring Device for Temperature and Strain of Electric Aerial Optical Cable

technical field

The utility model relates to the monitoring field of overhead power transmission lines, in particular to a temperature and strain distributed monitoring device for overhead optical cables of electric power.

Background technique

The overhead transmission line is an important link in the power system to realize the long-distance transmission of electric energy, and it is the artery of the power system. The traditional inspection of overhead transmission lines mainly relies on periodic inspections by operation and maintenance personnel, which has many limitations such as poor real-time performance and limited monitoring range. Electric overhead optical cable is a special overhead transmission line, mainly including 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 are the main carriers of power communication and dispatching, and are widely used . It is of great significance to strengthen the online monitoring of power overhead optical cables.

In recent years, the use of optical sensing systems in the field of on-line monitoring of power overhead optical cable lines has been proposed at home and abroad to realize the measurement of optical cable temperature, strain and other parameters. Chinese patent CN 201569523 U "A Stress and Strain Measuring Device Applied to Optical Fiber Composite Phase Line OPPC" consists of a distributed optical fiber system BOTDR based on Brillouin scattering, a monitoring computer, a conductive optical fiber and its splice box, and an optical fiber composite phase line OPPC It can complete the monitoring of OPPC stress and strain abnormal points. Chinese patent CN 203163769 U "an overhead line safety monitoring system based on distributed optical fiber sensors" consists of an overhead line stress sensing device, an overhead line temperature sensing device and an overhead line environment monitoring device, and its overhead line stress sensing device Based on the sensing principle of distributed optical fiber Brillouin time domain optical time domain reflectance (BOTDR), the overhead line temperature sensing device is based on the sensing principle of distributed optical fiber Raman temperature measurement (ROTDR), to realize the temperature measurement of the entire overhead transmission line Real-time online distributed monitoring. Chinese patent CN 102840928 A "an online temperature monitoring system and monitoring method for optical fiber composite phase line" and Chinese patent CN 203310540 U "an online temperature and strain monitoring device for fusion optical fiber composite phase line" propose to use multiple The mode fiber monitors the temperature of the running OPPC optical cable in real time, and the measurement distance does not exceed 20km, which cannot realize the real-time continuous monitoring of the long-distance OPPC. US Patent No. US7412117 (PCT/GB2004/004383) Apparatus and method for distributed temperature sensing, does not consider the complex heat conduction characteristics of OPPC lines, and does not consider the special performance of multi-point connection of overhead optical cables.

The above-mentioned patents all use BOTDR technology in OPPC stress monitoring, but the optical fiber composite phase line OPPC used for testing is a conventional structure, and the design principle of its structure (including optical units) is to make the optical fiber in the cable and the external temperature , Strains (especially strains) are isolated as much as possible to ensure reliable transmission of optical signals without external influences. Therefore, for conventional power overhead optical cables, the optical fiber has a redundant length (fiber excess length) relative to the optical unit, that is, the optical fiber is loose in the optical unit, and the optical unit is located in the twisted layer. At this time, the optical unit still exists compared to the optical cable. With a certain stranding excess length, when the electric overhead optical cable is strained within a certain range, the optical fiber in the cable will not be strained, so it needs to be improved in terms of the accuracy of OPPC stress monitoring.

Contents of the invention

The technical problem to be solved by the utility model is to provide a distributed temperature and strain monitoring device for electric overhead optical cables, which can effectively utilize redundant optical fibers inside the overhead optical cables to realize distributed temperature and strain measurement.

The technical scheme adopted by the utility model to solve the above-mentioned technical problems is: a distributed monitoring device for temperature and strain of electric overhead optical cables, which is characterized in that it includes a test host, overhead optical cables, and optical fiber splicing boxes, and the overhead optical cables are equipped with The first optical unit and the second optical unit, the first optical unit is located at the center layer of the overhead optical cable, the second optical unit is located at the twisted layer of the overhead optical cable, one port of the first optical unit is connected to the The first optical port of the test host is connected, the other port of the first optical unit is introduced into the optical fiber connection box, and one port of the second optical unit is connected to the second optical port of the test host. Port connection, the other port of the second optical unit is introduced into the fiber splicing box, the other port of the first optical unit is connected with the other port of the second optical unit in the The fiber splicing box is internally connected.

In an embodiment of the present invention, the first optical unit is built with at least one tight-buffered optical fiber with no excess length, and the second optical unit is built with at least one loose-buffered optical fiber with an excess length of 0.5-0.8%. optical fiber.

In an embodiment of the utility model, the test host has two optical ports, the first optical port has the function of sending continuous laser signals, the second optical port is used for sending pulsed laser signals, and has a Brillouin function for receiving feedback Spectrum signal function, the test host demodulates the fiber temperature and strain values after receiving the feedback signal from the second optical port.

In an embodiment of the present invention, the optical fiber splicing box has the functions of optical fiber fusion splicing protection and coiling redundant optical fibers.

Compared with the prior art, the utility model has the advantage of using the internal optical fiber of the power overhead optical cable to realize the distributed real-time measurement of the temperature and strain of the overhead line. By combining the existing software, it realizes no measurement blind area, no additional sensors are needed, and the construction is simple. , easy to implement; and the monitoring method has high measurement accuracy and precision, realizing the real-time monitoring of the whole transmission line with a length of no more than 75km, and the sampling interval of the line length is 0.1~1m; a set of temperature and strain data is measured every 20S, and the temperature accuracy Up to ±1°C, the temperature resolution is 0.1°C; the strain accuracy is up to ±20me, and the strain resolution is 20me. This monitoring method effectively improves the monitoring level of power overhead optical cables and ensures the safety of power transmission.

Description of drawings

Fig. 1 is a schematic diagram of a distributed monitoring device for temperature and strain of an electric overhead optical cable in the utility model.

Fig. 2 is a schematic cross-sectional view of an electric aerial optical cable with two built-in optical units in the utility model.

Detailed ways

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

FIG. 1 is a schematic diagram of the utility model, including: a test host 1 , an overhead optical cable 2 , and an optical fiber splice box 3 . The test host 1 has two optical ports, the first optical port 11 and the second optical port 12, which can realize distributed temperature and strain monitoring for tens of kilometers. The first optical port has the function of sending continuous laser signals, and the second port It is used to send pulsed laser signals and has the function of receiving feedback Brillouin spectrum signals. The test host demodulates the fiber temperature and strain values after receiving the feedback signals from the second optical port. In this embodiment, the overhead optical cable 2 is an optical fiber composite overhead phase line OPPC, which has the functions of power transmission and power communication. One port of the unit 21 is connected to the first optical port 11 of the test host 11, the other port of the first optical unit 21 is introduced into the fiber splicing box 3, and one port of the second optical unit 22 is connected to the second optical port 12 of the test host 1 , the other port of the second optical unit is introduced into the fiber splicing box 3, and the other port of the first optical unit inside the fiber splicing box 3 is connected to the other port of the second optical unit to form a fiber optic measurement circuit. The optical fiber splicing box 3 is a conventional outdoor type. The optical fiber in the optical fiber composite overhead phase line enters the optical fiber splicing box 3 after being photoelectrically separated, which can protect the optical fiber fusion splicing point and coil to store redundant optical fibers. In this embodiment, the test host 1 can use a Brillouin optical time domain analyzer.

The cross-sectional schematic diagram of the electric overhead optical cable with two built-in optical units is shown in Figure 2, including the first optical unit 21, the second optical unit 22, the aluminum wire 23, and the aluminum-clad steel wire 24. The first optical unit 21 is located in the electric overhead In the central layer of the optical cable 2, the first optical unit 21 is built with at least one tight-buffered optical fiber 211 without excess length, and the second optical unit 22 is located Loose-buffered fiber 221 with a length of 0.5-0.8%.

In this embodiment, the excess length of the loose-buffered optical fiber 221 is relatively large, which is related to the temperature of the overhead line, that is, its Brillouin spectrum information only reflects the temperature information of the overhead line; while the tight-buffered optical fiber 211 has no excess length, and does not exist The excess stranding length, the tight-buffered optical fiber 211 and the temperature and strain of the overhead line are simultaneously related. Combined with the Brillouin spectrum information of the loose-buffered optical fiber 221 (which is only related to temperature), the strain-affected Brillouin spectrum information of the tight-buffered optical fiber 211 can be separated, thereby realizing distributed monitoring of temperature and strain of power overhead lines. The real-time temperature and strain measurement information and long-term operation historical data of overhead power lines can reflect the health status of overhead lines, timely discover local hot spots, icing, broken strands and other faults of overhead lines, and improve the monitoring level of overhead line power transmission process , to ensure the safety of power transmission.

The above are the preferred embodiments of the utility model, and all changes made according to the technical solution of the utility model, when the functional effect produced does not exceed the scope of the technical solution of the utility model, all belong to the protection scope of the utility model.

Claims (4)

1. an electric aerial optical cable temperature and Strain Distribution formula monitoring device, it is characterized in that: comprise Test Host, aerial optical cable, fiber optic closure, the first smooth unit and the second smooth unit is provided with in described aerial optical cable, described first smooth unit is positioned at the central core of aerial optical cable, described second smooth unit is positioned at the stranded layer of aerial optical cable, described first smooth unit port is connected with the first optical port of described Test Host, the fiber optic closure described in the introducing of another port of the described first smooth unit is inner, described second smooth unit port is connected with the second optical port of described Test Host, the fiber optic closure described in the introducing of another port of the described second smooth unit is inner, another port of described first smooth unit is connected in described fiber optic closure inside with another port of the described second smooth unit.

2. a kind of electric aerial optical cable temperature as claimed in claim 1 and Strain Distribution formula monitoring device, it is characterized in that: built-in at least one of the described first smooth unit does not have remaining long tight tube fiber, the described second smooth unit is built-in with the loose tube fiber that more than at least one length is 0.5-0.8%.

3. a kind of electric aerial optical cable temperature as claimed in claim 1 and Strain Distribution formula monitoring device, is characterized in that: described Test Host has two optical ports; First optical port is for sending continuous laser signal; Second optical port, for sending pulsed laser signal, receives the brillouin frequency spectrum signal of feedback simultaneously; Described Test Host demodulates fiber optic temperature, strain value after the second optical port receives feedback signal.

4. a kind of electric aerial optical cable temperature as claimed in claim 1 and Strain Distribution formula monitoring device, is characterized in that described fiber optic closure has fused fiber splice protection, coiling excess fiber function.