CN105157596B - A kind of intelligent electric power comb DEFORMATION MONITORING SYSTEM - Google Patents

Abstract

The invention relates to an intelligent electric power pipe deformation monitoring system, which is used to sense the deformation of the electric power pipe in the electric power pipe transmission network. The system includes: distributed sensing optical fiber: arranged between two electric power pipe working wells The longitudinal reinforcement of the power pipe is used to transmit and return the sensing signal; the strain collector: connected to the distributed sensing fiber, sends the sensing signal to the distributed sensing fiber, and receives the echo signal to judge the power pipe. Deformation state; central server: communicate with the strain acquisition instrument, generate instructions to control the frequency, range and accuracy of the sensing signal sent by the strain acquisition instrument, and receive and store the deformation state data of the power pipe; on-site user terminal: through the wireless network at the maintenance site Communicate with the central server to obtain the deformation state data of the power pipe. Compared with the prior art, the present invention has the advantages of intelligent monitoring, precise positioning, cost saving and the like.

Description

An intelligent power pipe deformation monitoring system

technical field

The invention relates to the field of disaster prevention and reduction in geotechnical engineering, in particular to an intelligent power pipe deformation monitoring system.

Background technique

With the continuous deepening of my country's urbanization process, the city's demand for electricity is also growing exponentially. However, overhead lines have various disadvantages: small transmission capacity, large footprint, hindering city appearance, weak ability to resist natural disasters, frequent failures, and easy to cause safety accidents. Therefore, the use of power pipes and other methods to make power transmission facilities land has become the main way to solve the problem of urban power supply. At present, every city in the country has a huge power pipeline transmission network. As one of the city's lifeline projects, the power supply affects the whole body. How to take effective measures to sense the existing power grid to ensure its operation safety has become an urgent problem to be solved.

Power pipes are generally buried under the road, and the area under the road and adjacent areas are often the areas with the most frequent urban construction activities such as foundation pit excavation, subway construction, or other concealed crossing engineering construction. During this process, the power pipes, especially the outsourcing concrete, are prone to damage and cracking, thus losing the ability to protect the internal power cables and affecting their normal and safe operation, and the above phenomenon is especially serious in soft soil areas. However, as a shallow buried underground project, the concealment of power pipes makes it difficult to implement traditional monitoring methods, and the diameter of the cable pipe is small, and high-voltage cables run through it, so it is also difficult to deploy sensors inside the cable pipe. It can be seen that it is an objective requirement to realize the real-time perception of the pipe status by researching and realizing the self-perception of the pipe arrangement and establishing an intelligent pipe arrangement structure.

Intelligent structure is to embed various sensors and controllers inside the structure or use the characteristics of materials to make the structure have some bionic functions that people want, such as: self-sensing, self-diagnosis, self-regulation and repair. A new branch of disaster prevention and mitigation is also the development direction of future engineering structures. But whether it is the diagnosis of structural performance, or structural control and adjustment, it all depends on the accurate measurement of the real-time state of the structure.

Optical fiber monitoring technology is a new type of monitoring technology that monitors changes in physical characteristic parameters of light waves such as intensity (power), wavelength, frequency, phase, and polarization state during optical fiber transmission with the development of optical fiber communication technology in recent years. It has the advantages of high precision, high sensitivity, anti-electromagnetic interference, good electrical insulation, strong durability, suitable for long-term monitoring, plastic geometry, strong adaptability, small transmission loss, and long-distance detection. The optical fiber in the distributed optical fiber monitoring technology based on the principle of Liouin scattering is not only a transmission medium, but also a sensor, so it can achieve a fully distributed and seamless monitoring of the structure. However, at present, this technology has not been applied to the structural deformation of power pipes. self-awareness work. In order to apply the distributed optical fiber sensing technology to the deformation self-sensing operation of the power pipe, the following problems need to be solved:

1. The layout scheme of the sensing fiber in the power pipe, the efficient arrangement of the sensing fiber can obtain enough data for the discrimination of the deformation mode of the pipe, and can save the amount of fiber.

2. The method for judging the structural performance of the power pipe, how to use the monitored data to judge the deformation mode and working status of the power pipe.

3. Self-sensing system for power pipe deformation. The workflow of the system generally includes sensing, analysis, decision-making, processing, and re-sensing, so as to realize the automation and systematization of the entire sensing process.

Contents of the invention

The object of the present invention is to provide an intelligent power pipe deformation monitoring system with intelligent monitoring, accurate positioning and cost saving in order to overcome the above-mentioned defects in the prior art.

The purpose of the present invention can be achieved through the following technical solutions:

An intelligent power pipe deformation monitoring system is used to sense the deformation of the power pipe in the power pipe transmission network. The system includes:

Distributed sensing optical fiber: set on the longitudinal reinforcement of the power pipe between two power pipe work wells, to transmit and return the sensing signal;

Strain collector: connected to the distributed sensing optical fiber, sends sensing signals to the distributed sensing optical fiber, and receives the echo signal to judge the deformation state of the power pipe;

Central server: communicate with the strain collector, generate instructions to control the frequency, range and accuracy of the sensing signal sent by the strain collector, and receive and store the deformation state data of the power pipe;

On-site user terminal: communicate with the central server through the wireless network at the maintenance site to obtain the deformation state data of the power pipe.

The longitudinal steel bars are provided in multiple pieces and cast integrally with the power pipes, and are respectively arranged at the top corners of the cross-section of the power pipes and the midpoint between adjacent top corners.

A plurality of distributed sensing optical fibers are provided in the same section of power pipe, and each distributed sensing optical fiber is bound parallel to the corresponding longitudinal steel bar in a stretched state.

Both ends of the power pipe are provided with openings, and each distributed sensing optical fiber extends out of the opening to connect with the sensing fiber of the adjacent power pipe.

The joints from the opening of the power pipe to the distributed sensing optical fiber in the power pipe working well are wrapped with geotextile or nested with bellows.

A detection method for an intelligent power pipe deformation monitoring system, comprising the following steps:

1) Set induction signals with different sampling frequency, spatial resolution and precision according to different power pipes;

2) Obtain the original induction signal strain value of the initial test when the power pipe is completed;

3) Real-time acquisition of the strain value of the test induction signal when the power pipe is working;

4) If the difference between the strain value of the original induction signal and the strain value of the test induction signal is greater than the set threshold, it is determined that there is deformation or crack in the section of electric pipe, and proceed to step 5);

5) According to the spatial distribution diagram of the echo of the test induction signal, the position and direction of the deformation or crack of the section of electric pipe are obtained, and the size of the deformation or crack is obtained according to the magnitude of the difference.

Compared with the prior art, the present invention has the following advantages:

The present invention is a system for self-sensing the deformation of the power pipe structure based on distributed optical fiber sensing technology, which can accurately locate the deformation, damage, and cracking of the pipe structure, and evaluate the impact. The performance of each pipe structure in the entire power pipe network can be monitored in real time, accurately and efficiently, realizing the intelligence of the power pipe deformation sensing system, saving a lot of manpower and material costs, and improving the deformation of the power pipe during the operation period. It has a good application prospect in monitoring, structural performance diagnosis, and maintenance of power drainage network.

Description of drawings

Fig. 1 is a schematic diagram of the power pipe arrangement structure and its internal distributed optical fiber layout position according to the present invention.

Fig. 2 is a typical discriminant curve of the deformation of the electric power pipe in the embodiment.

Fig. 3 is a typical discriminant curve of the defect of the electric power pipe in the embodiment, wherein, Fig. (3a) is the strain curve of the top surface of the defect, and Fig. (3b) is the strain curve of the bottom surface of the defect.

Detailed ways

The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

Example:

The distributed sensing fiber is implanted in a specific position of the concrete structure of the power pipe. When the power pipe structure is deformed, the distributed sensing fiber inside it will be deformed accordingly, so that the distributed sensing fiber can be used to respond to the strain. The sensing characteristics of the structure, the strain value of each section of the structure can be collected by using the distributed optical fiber strain analyzer, so as to obtain the deformation state of the structure where the distributed sensing optical fiber is buried. Comparing the difference between the strain values at different positions in the same section of the structure, the strain distribution at each point of the section can be obtained, so that it can be accurately judged whether the section of the power pipe structure is subsidence, uplift or lateral deformation, and can Evaluate the damage to the structure caused by such deformations, the exact location and size of the cracks.

The ordinary single-mode distributed sensing optical fiber covered with rubber protection is prepared in advance. During the construction of the power pipeline, the distributed sensing optical fiber is bound to the longitudinal steel bar and cast into shape. The sensing optical fiber is introduced into the working well of the power pipe, and is wrapped with geotextile or nested with bellows during the construction period to protect the optical fiber joint leading to the working well of the power pipe.

After the construction of the pipeline structure is completed, a plurality of distributed sensing optical fibers embedded in the power pipeline structure are connected end to end, and connected in series to form a power pipeline optical fiber monitoring network, which is finally connected to the optical fiber strain analyzer for data processing and analysis. The deformation sensing system of the power pipe structure composed of equipment can obtain the deformation and temperature changes in the structure, and store or output the data to the on-site user terminal.

The power pipe structure is continuously monitored, so as to obtain the strain value of each point along the distributed sensing optical fiber in the power pipe structure at each time. The difference between the strain value and the initial test strain value obtained after the completion of the pipe construction is Additional strains that occur during the operation period of the power pipeline. According to the measured strain, the deformation value along the distributed sensing optical fiber arrangement position within a certain distance of the pipe can be calculated. The position where the additional strain of the structure is measured is the position where the pipe is deformed.

According to the difference in the measured strain values of the top surface, bottom surface and side distributed sensing optical fiber arranged in the same section, according to the beam deflection line calculation method, the bending direction, deflection, and defect of the pipe at this point can be obtained . According to the concrete label and its maximum allowable tensile and compressive strain value and the additional strain value of this point, the cracking of the pipe structure at this point can be judged.

The arrangement position of the distributed sensing optical fiber in the pipe is very important. The distributed sensing optical fiber is arranged at the four midpoints and four corners of the four sides of the pipe structure, and the longitudinal steel bars in the structure are arranged along the direction of the pipe. superior. Its two ends are introduced into the end well, and a surplus amount that can span the length of the end well to the place where the optical fiber is buried in the next row of pipes is reserved. During the laying process, keep the optical fiber parallel to the direction of the pipe, and maintain a certain tension.

(1) Constructing the deformation sensing network of intelligent electric power pipe structure

As shown in Figure 1, four distributed sensing optical fibers are arranged longitudinally at the four midpoints and corner points of the four sides of the power pipe section. When laying, the optical fiber is straightened, and the optical fiber is bound to the longitudinal steel bar with a cable tie while maintaining a certain pre-tightening force. This is to enable the optical fiber to deform cooperatively with the structure, so as to accurately measure the deformation of each point of the structure. The two ends of the optical fiber are introduced into the working well, and the concrete main structure is poured. After the construction period is over, the optical fibers of the multi-section pipes will be connected end to end to form an intelligent power pipe deformation monitoring network, and connected to the optical fiber strain analyzer.

Data Acquisition and Analysis

In the central server, parameters such as sampling frequency, spatial resolution, and precision are reasonably set according to the structural properties and deformation development of each section of intelligent power pipes, and then continuous data collection is carried out. When the local data changes greatly, the sampling frequency is increased. More accurately grasp the development status of structural deformation.

As shown in Figure 2, the data analysis process includes, according to the spatial distribution data of structural strain, the location of structural deformation, the location of structural defects and the location of cracks, and the direction of structural bending deformation can be determined.

As shown in Figures 3a and 3b, the difference between the strain value obtained by real-time sampling and the initial test strain value when the structure is completed is calculated to obtain the structural strain value. From this value the stress, deflection, crack size of the structure is calculated.

Claims (1)

1. a kind of intelligent electric power comb DEFORMATION MONITORING SYSTEM, to perceive the shape of the electricity channel in electricity channel power transmission network Become, which is characterized in that the system includes：

Distributed sensing fiber：It is arranged on the longitudinal reinforcement of the electricity channel between two electricity channel active wells, to pass Inductive signal is passed and returns, the longitudinal reinforcement is equipped with a plurality of and is molded with electricity channel formed by integrally casting, is separately positioned on electricity Midpoint between the apex angle and adjacent apex angle of power comb cross section, the distributed sensing fiber are arranged in same section of electric power Pipe in be equipped with it is a plurality of, every distributed sensing fiber under tensile state it is parallel binding on corresponding longitudinal reinforcement, it is described The both ends of electricity channel are equipped with opening, and every distributed sensing fiber stretches out opening and the sensor fibre of adjacent power comb connects It connects, the connector of the distributed sensing fiber in the opening to electricity channel active well of the electricity channel passes through geotechnological cloth bag It wraps up in or bellows is nested；

Strain acquirement instrument：It is connect with distributed sensing fiber, inductive signal is sent to distributed sensing fiber, and receive echo letter Number, judge the deformation state of electricity channel；

Central server：It is communicated with strain acquirement instrument, generates frequency, range that instruction controlled strain Acquisition Instrument sends inductive signal And precision, and receive and store the deformation state data of electricity channel；

Onsite user's terminal：It is communicated with central server by wireless network in Overhaul site, obtains the change shape of electricity channel State data；

Using the detection method of intelligent electric power comb DEFORMATION MONITORING SYSTEM, include the following steps：

1) inductive signal of different sample frequencys, spatial resolution and precision is set according to different electricity channels；

2) the original inductive signal strain value that acquisition electricity channel complete working hour initially tests；

3) test inductive signal strain value when electricity channel work is obtained in real time；

If 4) existing difference is more than the threshold value set between original inductive signal strain value and test inductive signal strain value, Judging this section of electricity channel, there are deformation or cracks, and carry out step 5)；

5) it according to the spatial distribution map of the echo of test inductive signal, obtains this section of electricity channel and deforms upon or the position in crack And direction, according to the acquiring size deformation of difference or the size in crack.