JP2007183166A - Utility pole stress evaluator, utility pole stress evaluation system, utility pole stress evaluation method, and utility pole - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a utility pole, a utility pole stress evaluator, a utility pole stress evaluation system, and a utility pole stress evaluation method, for appropriately evaluating stresses in the whole of the utility pole. <P>SOLUTION: This utility pole comprises a concrete pole for supporting electric wire, one continuous optical fiber cable disposed within the concrete of the concrete pole in the longitudinal direction of the concrete pole, and a take-out port for taking out one end of the fiber cable. As the result of causing pulse light to enter the fiber cable, which is taken out through the take-out port, from one end of the fiber cable toward the other end, the reflective light is received corresponding to the pulse light between the one end and the other end to evaluate the stress on the concrete pole based on the received light power of the received reflective light. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a utility pole stress evaluation apparatus, a utility pole stress evaluation system, a utility pole stress evaluation method, and a utility pole.

  Electric poles, which are familiar to our living environment, have been studied for strength by calculating the electrical line and wind pressure weight from the type and overhead line information based on the electrical equipment technical standards, Since it passed a strict shipping test such as a non-destructive test, it is considered that there is not much necessity to perform maintenance and management from the usual day.

  However, utility poles that are distorted due to unbalanced loads are unstable both in terms of material and dynamics, leading to a decrease in strength due to cracks and fatigue, and sudden occurrences of wind and snow, earthquakes, etc. There is a risk of collapse due to the load. Therefore, in view of unexpected load conditions and sudden abnormal weather, etc., it is an index that indicates the degree of distortion of the utility pole, and it is known that `` stress '' is proportional to the strain by the Hooke's law. Need to be monitored from the usual time.

  “Stress” refers to the force acting on an arbitrary virtual surface of a unit area in an object to which an external force acts, and includes tensile stress, compressive stress, and shear stress. . The tensile stress means, for example, a stress generated when a deformation is caused when the rubber is stretched, and can be easily calculated by dividing the force F applied perpendicularly to the cross-sectional area A by the cross-sectional area A. The compressive stress means, for example, stress generated when a hard ball is compressed, and can be calculated in the same manner as tensile stress. The shear stress means a stress generated when the object is deformed obliquely, and can be easily calculated by dividing the force F applied in parallel to the cross-sectional area A by the cross-sectional area A.

  Conventionally, a method based on visual confirmation by a measurer for distortion of an electric pole has been common, but in view of the point that quantitative measurement is difficult by visual confirmation, for example, in Patent Document 1 shown below, an entire image of an electric pole Is a technique for diagnosing the degree of health of a power pole by quantitatively grasping the degree of distortion of the power pole by performing image processing on the image from the ground and performing image processing on the captured image (hereinafter referred to as Conventional Technology 1). It is disclosed.

Further, for example, in Patent Document 2 shown below, a concrete column is obtained by embedding a load cell (load converter) integrally with a concrete column such as a utility pole, and dividing the cross-sectional area into the load detected by the load cell. A technique for measuring effective body stress (hereinafter referred to as Conventional Technique 2) is disclosed. In addition to the load cell, there is a mechanism in which displacement meters such as extensometers and inclinometers are installed at locations where the concrete structure may be deformed, and the degree of deformation of the concrete structure is measured by the displacement meter. Generally known.
JP-A-6-94442 JP 7-159259 A

However, the above-described conventional techniques 1 and 2 have the following problems.
In the prior art 1, of course, distortion may be confirmed by monitoring the appearance of the utility pole, but the situation inside the utility pole cannot be confirmed only by monitoring the appearance, and risk prediction according to the situation inside the utility pole, etc. There was a problem that could not be performed accurately. In addition, for monitoring by the imager from an imaging position fixed from the ground plane, especially the situation from one end of the utility pole to the other end in the longitudinal direction, that is, the overall situation including the outside and inside of the utility pole There was also a problem that it was difficult to grasp accurately.

  In the prior art 2, a sensor such as a load cell or a displacement meter is disposed at a predetermined position where the utility pole is located, but only one point can be measured with one sensor. For this reason, when it is desired to continuously and closely monitor the entire situation including the outside and inside of the utility pole, a large number of sensors must be arranged inside the utility pole, which is too expensive and practically realized. There was a problem that it was difficult.

  The main present invention for solving the above-mentioned problems is a concrete column that supports electric wires, a single continuous optical fiber cable disposed inside the concrete of the concrete column toward the longitudinal direction of the concrete column, An electric pole having an opening at a predetermined position of the concrete pole to take out one end of the optical fiber cable, and the other end from the one end of the optical fiber cable taken out from the outlet As a result of the incidence of the pulsed light toward the light source, the light receiving power of the reflected light corresponding to the pulsed light between the one end and the other end is detected, and the light receiving power and the emission of the pulsed light are used to detect the light receiving power. Based on the time required to receive the reflected light, obtain a level diagram of the received light power with respect to the distance of the optical fiber cable. Based on the deviation between the reference level diagram that has been preset with the obtained level diagram, evaluating stress of the concrete column, and that.

  ADVANTAGE OF THE INVENTION According to this invention, the utility pole, the utility pole stress evaluation apparatus, the utility pole stress evaluation system, and the utility pole stress evaluation method which can evaluate the stress of the whole utility pole appropriately can be provided.

<Pole>
=== Overview of OTDR ===
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical fiber cable that has recently attracted attention as a communication infrastructure in the field of information communication, and backscattering using OTDR (Optical Time Domain Reflectometry) adopted in a loss test when the optical fiber cable is installed. This is a technique in which the light method is applied to stress evaluation of utility poles. For OTDR, B-OTDR (Brillouin OTDR) using Brillouin backscattered light, C-OTDR (Coherent OTDR) using frequency modulated pulses, and Raman scattered light can be used to measure the temperature of optical fiber cables. Also included are R-OTDR (Ramman OTDR) and the like.

  Here, the outline of the loss test of the optical fiber cable by the backscattered light method using OTDR will be described based on FIGS. 2A and 2B with reference to the flowchart shown in FIG. First, an OTDR 800 which is an optical pulse tester is connected to the optical fiber cable 810 to be tested. One end of the optical fiber cable 810 connected to the OTDR 800 is a point, and the other end is a point b.

  Under such circumstances, the OTDR 800 makes an optical pulse incident from point a to point b of the optical fiber cable 810 (S300). At this time, a boundary surface of materials having different refractive indexes is formed at a point a which is a connection point with the OTDR 800 and is an incident end of an optical pulse and a point b which is an end of the optical fiber cable 810. As a result, “Fresnel reflected light” returns to point a. Further, “Rayleigh scattering”, which is a potential scattering loss, occurs between points a and b of the optical fiber cable 810, and as a result, “backscattered light” returns to the point a.

  Fresnel reflected light and backscattered light (hereinafter referred to as “reflected light”) return to point a over a delay time proportional to the distance from point a to the reflecting point. The OTDR 800 receives the reflected light that has returned in response to the incidence of the light pulse (S301), and the light reception power of the reflected light and the time from the incidence of the light pulse until the reflected light is received, that is, up to the reflection point. The distance is detected (S302).

  In order to improve the measurement accuracy, the OTDR 800 repeats the processing from S300 to S301 for a predetermined N times (S303), and averages the data for the N times of the distance to the reflection point and the received light power. As a result, the OTDR 800 calculates a “level diagram” in which the horizontal axis is the distance (m) from point a to point b and the vertical axis is the received light power (dB) of the reflected light (S304). Hereinafter, the processing from S301 to S304 illustrated in FIG. 3 is referred to as “OTDR measurement processing”.

  By the way, the rate at which the light pulse is converted to the reflected light can be considered to be uniform at each point in the longitudinal direction of the optical fiber cable 810, so that the reflection point is located far from the point a at the incident end. The light receiving power of the reflected light returning from the reflection point to the point a at the incident end can be regarded as being attenuated substantially constant. Therefore, the waveform of the level diagram acquired by the OTDR 800 shows a substantially constant slope except for the portion where Fresnel reflection occurs, and the loss factor of the optical fiber cable 810 can be obtained based on the slope of the waveform. it can. Then, the OTDR 800 graphically displays the evaluation result such as the level diagram and the loss coefficient on the monitor screen mounted on itself (S305).

  By the way, at an arbitrary point c located between points a and b of the optical fiber cable 810 shown in FIG. 2A, the axis of the optical fiber cable 810 slightly bends due to a lateral pressure due to an external factor, so that the micro pending. Suppose a loss occurs. At this time, the level diagram acquired by the OTDR 800 is as shown in FIG. That is, as the distance from the point a at the incident end increases, the received light power attenuates substantially constant, but at the point c, a discontinuous change in received light power appears due to micropending loss. Therefore, the level diagram acquired by the OTDR 800 is compared with the predetermined reference level diagram (the received light power has a substantially constant attenuation characteristic according to the distance) in which micropending loss does not occur. By analyzing the deviation (difference in received light power for each distance), it is possible to detect a location where micropending loss occurs in the optical fiber cable 810, that is, a location where stress is generated.

=== One Example of Stress Evaluation of Utility Pole ===
FIG. 1 is a diagram showing an example in which an evaluator goes to the site to perform stress evaluation of a utility pole.

  Inside the electric pole 100 that supports the electric wire, a single continuous optical fiber cable 200 is arranged in advance in the longitudinal direction of the electric pole 100 as a stress evaluation sensor. The optical fiber cable 200 is disposed so as to cover the entire cross section from one end to the other end of the utility pole 100 in the longitudinal direction so as to measure stress over the entire longitudinal direction of the utility pole 100. . As a result, the entire stress of the utility pole 100 can be measured by one OTDR measurement process.

  In the vicinity of the ground plane of the utility pole 100 (for example, from the ground plane to the average height of an adult), an extraction port 110 for taking out one end (incident end) of the optical fiber cable 200 is provided. The take-out port 110 not only exposes one end of the optical fiber cable 200 in a bare state, but also functions as a connector for an external device such as a utility pole stress evaluation device 300 such as a commercial power outlet. It shall have.

  As shown in FIG. 1, in the case of on-site measurement, only one input end of the optical fiber cable 200 may be taken out from the outlet 110 near the ground plane of the utility pole 100. Therefore, in this case, it is not necessary to take out the other end of the optical fiber cable 200 from the takeout port 110, and the open state is set inside the utility pole 100. The outlet 110 is provided with an inclination on the ground plane side from the inside of the utility pole 100 to the outside for the purpose of increasing the bending radius of the optical fiber cable 200 and preventing the intrusion of rainwater. It is preferable to do this.

  Although details will be described later, as shown in FIG. 10, optical fiber cables 200 respectively arranged on a plurality of utility poles 100 constituting one electric power system are connected by a daisy chain (a large number of cables such as a rosary are connected to one another). In the case where the stresses of the plurality of utility poles 100 are collectively evaluated, it is necessary to take out both ends of the optical fiber cable 200 from the outlet 110 provided near the electric wire support position of the utility pole 100. . Also in this case, for the same reason as described above, the take-out port 110 is preferably disposed so as to be inclined toward the ground plane from the inside of the utility pole 100 toward the outside.

  The evaluator carries the utility pole stress evaluation device 300 having the same function as that of the OTDR 800 and goes to the utility pole 100 at the site, and the utility pole stress evaluation device 300 is taken out directly or via the same type of optical fiber cable 201. Connect with. Then, the evaluator activates the utility pole stress evaluation apparatus 300 and checks the evaluation result of the overall stress of the utility pole 100 by comparing the level diagram acquired this time with the reference level diagram on the monitor screen.

  In this way, the evaluator can use the utility pole stress evaluation apparatus 300 to continuously and densely grasp the state of stress applied to the entire utility pole 100. By the way, if the stress exceeds a certain amount, water tends to enter the utility pole 100 and the strength may be insufficient. For this reason, by assessing the stress of the utility pole 100 quantitatively rather than externally, the evaluator can easily and accurately grasp abnormal places such as cracks and fatigue of the utility pole 100 and focus on the abnormal places. It is possible to inspect.

=== In case of folding laying ===
By the way, the optical fiber cable 200 is folded and disposed inside the utility pole 100 so that the distance in the longitudinal direction of the utility pole 100 is reciprocated at least once, rather than being disposed inside the utility pole 100 without being folded back. As a result, it is preferable that a plurality of optical fiber cables 200 appear in the cross section of the utility pole 100 perpendicular to the longitudinal direction of the utility pole 100. In this case, the utility pole stress evaluation apparatus 300 continuously and densely applies the stress for each section of the utility pole 100 based on the received light power on the level diagram at a plurality of locations of the optical fiber cable 200 that appears for each section of the utility pole 100. It becomes possible to evaluate. Further, by comprehensively analyzing the stress of the optical fiber cable 200 at a plurality of locations appearing on each cross section of the utility pole 100, the stress for each cross section of the utility pole 100 can be evaluated with high accuracy.

=== Section analysis with 3 cores or more ===
FIG. 4A is a perspective view of the utility pole 100 when a single continuous optical fiber cable 200 is folded four times in total and disposed inside the utility pole 100, and FIG. 4B is a utility pole in this case. FIG.

  As shown in FIG. 4A, the outlet 110 is the origin of the three-dimensional coordinate axis, and the direction from the origin of the coordinate axis to the U surface on one end side in the longitudinal direction of the utility pole 100 is the positive axis of the Z axis. The direction from the origin of the coordinate axis to the B surface on the other end side in the longitudinal direction of the utility pole 100 is the negative direction of the Z axis.

  The optical fiber cable 200 bent near the outlet 110 is arranged in a straight line with the inside of the utility pole 100 facing the positive direction of the Z axis. Then, the optical fiber cable 200 penetrates the a1 point on the U surface and is folded back to the a2 point at a position shifted by 90 degrees from the a1 point.

  The optical fiber cable 200 folded back to point a2 on the U plane is linearly arranged with the inside of the utility pole 100 facing the negative direction of the Z axis. Then, the optical fiber cable 200 passes through the a3 point on the B surface having the same X and Y coordinates as the a2 point on the U surface, and is folded back to the a4 point at a position shifted by 180 degrees from the a3 point.

  Again, the optical fiber cable 200 folded back to point a4 on the B surface is linearly arranged with the inside of the utility pole 100 facing the positive direction of the Z axis. The optical fiber cable 200 passes through the a4 point on the B surface and the a5 point on the U surface having the same X and Y coordinates, and is folded back to the a6 point at a position shifted by 90 degrees from the a5 point.

  Further, the optical fiber cable 200 folded back to point a6 on the U plane is linearly arranged with the inside of the utility pole 100 facing the negative direction of the Z axis. Then, the optical fiber cable 200 passes through the a6 point on the U surface and the a7 point on the B surface having the same X and Y coordinates, and is folded back to the a8 point at a position shifted by 180 degrees from the a7 point. The optical fiber cable 200 folded back to point a8 on the B surface is left open inside the utility pole 100 without returning to the outlet 110.

  As described above, the case shown in FIG. 4A can be regarded as if the four-core optical fiber cable 200 has the utility poles 100 arranged in parallel in the longitudinal direction. Further, in this case, as shown in FIG. 4B, each cross section of the utility pole 100 is in a state where the optical fiber cables 200 are arranged at four locations no matter where the cross section is taken, as if Kintarou. .

  In addition, as shown in FIG.4 (b), the cylindrical space | gap is provided in the inside of the utility pole 100, and the concrete pillar 102 is formed in the outer peripheral part of the space | gap. Inside the concrete pillar 102, a plurality of reinforcing bars 101 are disposed in the Z-axis direction, and the optical fiber cable 200 is disposed at a position excluding the reinforcing bars 101. In order to prevent erroneous detection of the optical fiber cable 200, the optical fiber cable 200 may be embedded in the reinforcing bar 101.

  Here, since there are three planes, the plane is specified. Therefore, analysis is performed based on the level diagram obtained from the states of the four optical fiber cables 200 included in each cross section of the utility pole 100, thereby adding to each cross section. In addition to the amount of stress itself, the direction in which the stress is applied can be specified. In addition, since the single optical fiber cable 200 is folded and disposed, all the stress states of each cross section from the B surface to the U surface in the longitudinal direction of the utility pole 100 are covered by one measurement. It becomes possible to analyze. As described above, since the plane is determined as long as there are three points, the embodiment is not limited to the embodiment shown in FIG. 4A, and may be an embodiment in which the optical fiber cable 200 is folded at least three times on the U surface or the B surface. .

  FIG. 5A is a diagram illustrating a state of a cross section of the U surface of the optical fiber cable 200 illustrated in FIG. 4A and a level diagram acquired by the utility pole stress evaluation apparatus 300. FIG. FIG. 5B shows that when a lateral pressure is applied from the negative side of the X axis to the positive side on the U plane, in other words, a compressive force is applied at the point a1 and a tensile force is applied at the point a6. It is the figure which showed the condition of the cross section of the U surface in the case of being applied, and the level diagram acquired by the utility pole stress evaluation apparatus 300 in this case.

  As shown in FIG. 5A, when no lateral pressure is applied to the U surface, the received light power increases as the distance from the incident end of the optical fiber cable 200 connected to the extraction port 110 toward the end increases. Attenuation is substantially constant except for loss due to reflected light. Therefore, the a1 point, a2 point, a5 point, and a6 point on the U plane have the same slope (loss factor) in the waveform of the level diagram of the OTDR measurement result.

  On the other hand, as shown in FIG. 5B, when a side pressure is applied to the U plane, at the points a1, a2, a5, and a6 on the U plane, in the worst case, the X and Y coordinates A compressive force and a tensile force are applied to such an extent that a distortion that shifts the position occurs. Therefore, micropending loss occurs at points a1, a2, a5, and a6 on the U plane, and a discontinuous change in optical power appears in the waveform of the level diagram that is the OTDR measurement result.

  In this manner, the utility pole stress evaluation apparatus 300 has a discontinuous change in received light power at a total of four locations of the optical fiber cable 200 that appears for each longitudinal section of the utility pole 100 based on the level diagram that is the OTDR measurement result. By confirming whether or not appears, it is possible to specify the presence / absence of a lateral pressure to the utility pole 100 from the outside and the location where the lateral pressure is generated. Further, the discontinuous change amount (deviation) of the received light power on the level diagram can be regarded as an index value indicating the stress generated by the lateral pressure with respect to the utility pole 100. For example, the average value of the amount of change in the received light power at each of the four locations of the optical fiber cable 200 that appears in the cross section of the utility pole 100 is regarded as the stress of the utility pole 100 in the target cross section. Furthermore, the direction of the stress applied to the cross section to be evaluated can be specified by relative comparison of the amount of change in the received light power at each of the four positions of the optical fiber cable 200 that appears in the cross section of the utility pole 100.

=== In the case of spiral laying ===
FIG. 6A is a perspective view of the utility pole 100 when one continuous optical fiber cable 200 is spirally arranged inside the utility pole 100, and FIG. 6B is a diagram of the utility pole 100 in such a case. It is sectional drawing.

  As shown in FIG. 6A, the outlet 110 is the origin of the three-dimensional coordinate axis, and the direction from the origin of the coordinate axis toward the U surface on one end side in the longitudinal direction of the utility pole 100 is the positive axis of the Z axis. The direction from the origin of the coordinate axis to the B surface on the other end side in the longitudinal direction of the utility pole 100 is the negative direction of the Z axis.

  The optical fiber cable 200 bent near the outlet 110 is arranged in a spiral shape at a constant pitch with the inside of the utility pole 100 facing the positive direction of the Z axis. Then, the optical fiber cable 200 penetrates the point b1 on the U surface and is folded back to a point b2 that is 180 degrees away from the point b1.

  The optical fiber cable 200 folded back to the point b2 on the U plane is spirally arranged at a constant pitch with the inside of the utility pole 100 facing the negative direction of the Z axis. Then, the optical fiber cable 200 penetrates the b3 point on the B surface and is folded back to the b4 point at a position shifted by 180 degrees from the b3 point. In addition, the optical fiber cable 200 folded back to the point b4 on the B surface is brought into an open state inside the utility pole 100 without returning to the extraction port 110.

  As a result, as shown in FIG. 6B, in each cross section of the utility pole 100, two optical fiber cables 200 appear with the X and Y coordinate positions changed according to a predetermined helical pitch. That is, according to the arrangement method of the optical fiber cable 200 shown in FIG. 4A, the appearance positions of the four optical fiber cables 200 appearing in each cross section of the utility pole 100 are always constant, but FIG. According to the arrangement method of the optical fiber cable 200 shown in a), the appearance positions of the two optical fiber cables 200 appearing in each cross section of the utility pole 100 are changed.

  Therefore, since it is impossible to predict in which direction the lateral pressure is applied from the outside toward the utility pole 100, when compared with the arrangement method of the optical fiber cable 200 shown in FIG. According to the arrangement method of the optical fiber cable 200 shown in a), the degree of freedom of the sensor position for stress evaluation of the utility pole 100 is increased, and consequently the accuracy of stress evaluation of the utility pole 100 is improved.

  FIG. 7A is a diagram illustrating the state of the cross sections of the U surface and the B surface of the optical fiber cable 200 illustrated in FIG. 6A and the level diagram obtained by the utility pole stress evaluation apparatus 300. FIG. FIG. 7B shows the situation of the cross section of the U plane when the side pressure is applied from the negative side of the X axis to the positive side of the U plane, the situation of the cross section of the B plane, and the evaluation of the utility pole stress in this case. FIG. 6 shows a level diagram acquired by the device 300.

  As shown in FIG. 7A, when no lateral pressure is applied to the U surface and the B surface, the distance from the incident end of the optical fiber cable 200 connected to the extraction port 110 toward the end increases. The received light power is attenuated substantially constant except for the loss due to Fresnel reflected light. Therefore, the b1 point and b2 point on the U plane and the b3 point and b4 point on the B plane have the same slope (loss factor) in the waveform of the level diagram of the OTDR measurement result.

  On the other hand, as shown in FIG. 7B, when a lateral pressure is applied to the U surface, at the b1 point and b2 point on the U surface, the positions of the X and Y coordinates are shifted in the worst case. The compressive force and tensile force are applied to such an extent that the above distortion occurs. Therefore, micropending loss occurs at points b1 and b2 on the U plane, and a discontinuous change in the received light power appears in the waveform of the level diagram as the OTDR measurement result. Since no side pressure is applied to the B surface, the points b3 and b4 on the surface B show the same inclination as in FIG. 7A in the waveform of the level diagram of the OTDR measurement result.

  Thus, since the appearance positions on the X and Y coordinates of the two optical fiber cables 200 are shifted between the U surface and the B surface, it could not be detected that a lateral pressure is applied to the B surface. However, it can be detected that a lateral pressure is applied to the U surface. That is, in this respect, it can be said that the degree of freedom of the sensor position for the stress evaluation of the utility pole 100 is increased.

<Pole stress evaluation device>
=== Configuration of Power Stress Evaluation Apparatus ===
FIG. 8 is a diagram illustrating a configuration of a utility pole stress evaluation apparatus 300 according to an embodiment of the present invention.

  The utility pole stress evaluation apparatus 300 is mainly configured by a laser diode 301, an optical coupler 302, a light receiving unit 303, a signal processing unit 304, a memory 305, a display unit 306, and an interface 307.

The laser diode 301 is a light emitting element that emits an optical pulse at a predetermined timing designated by the signal processing unit 304.
The optical coupler 302 is an element for causing the optical pulse emitted from the laser diode 301 to enter the extraction port 110 of the utility pole 100, that is, one end in the longitudinal direction of the optical fiber cable 200. In the optical fiber cable 100, the optical pulse is directly transmitted to the other end in the longitudinal direction of the optical fiber cable 100, and a part thereof is reflected light to one end of the optical fiber cable 100. And come back.
The light receiving unit 303 is an element that receives the returned reflected light via the optical coupler 302 and converts it into an electric signal indicating the light receiving power of the reflected light.

  The signal processing unit 304 detects the light receiving power of the reflected light based on the reflected light converted into the electric signal, and based on the time from the incident light pulse to receiving the reflected light, Calculate the distance to the generated reflection point. Note that the data of the distance from the reflection point and the received light power are stored in the memory 305 in order to obtain a level diagram by statistical calculation processing or the like. Further, the signal processing unit 304 controls the timing at which the laser diode 301 repeatedly emits light pulses for the averaging process. Further, the signal processing unit 304 calculates a level diagram in which the horizontal axis indicates the distance and the vertical axis indicates the received light power based on the predetermined number of distances and received light power data stored in the memory 305. The utility pole stress evaluation process to be described later is executed using the diagram.

The display unit 306 graphically displays a level diagram finally determined by the signal processing unit 304, a stress evaluation result, and the like.
The interface 307 is an interface for connecting the utility pole stress evaluation apparatus 300 to one end of the optical fiber cable 200 drawn out from the outlet 110 of the utility pole 100 via the same type of optical fiber cable 201.

=== Operation of Power Stress Evaluation Apparatus ===
FIG. 9 is a flowchart showing the operation of the utility pole stress evaluation apparatus 300 according to an embodiment of the present invention. Note that the utility pole stress evaluation apparatus 300 performs in advance OTDR measurement processing (processing from S300 to S304 shown in FIG. 3) on the utility pole 100 to be evaluated. As a result, it is assumed that a reference level diagram in an initial state without stress is stored in the memory 305 in advance.

  First, the utility pole stress evaluation apparatus 300 performs the above-described OTDR measurement process on the utility pole 100 to be evaluated this time (S900). As a result, a level diagram, which is the current OTDR measurement result, is obtained.

  Next, the utility pole stress evaluation apparatus 300 selects a plurality of verification points that specify an arbitrary cross section of the utility pole 100 based on the level diagram acquired this time (S901). The plurality of verification points are, for example, points a1, a2, a5, and a6 on the U plane shown in FIG. 4B, and, for example, on the U plane shown in FIG. 6B. B1 point and b2 point.

  Then, the utility pole stress evaluation apparatus 300 compares the currently acquired level diagram with the reference level diagram for each of the plurality of selected verification points, and verifies whether or not the received light power has changed by a predetermined amount or more (S902). ). For example, a sharp change in received light power at points a1, a2, a5, and a6 on the U surface shown in FIG. 5B, or b1 points on the U surface shown in FIG. 7B, b2 This corresponds to a sharp change in the received light power of a point.

  Here, when the light receiving powers of the plurality of selected verification points have not changed by a predetermined amount or more (S903: NO), until the verification covering all the cross sections of the utility pole 100 is completed (S904: YES), the utility pole stress The evaluation apparatus 300 repeatedly executes the processing from S901 to S904. When the light reception power has not changed by a predetermined amount or more in all cross sections of the utility pole 100 (S903: NO, S904: YES), the utility pole stress evaluation apparatus 300 indicates that the utility pole 100 is not stressed, The level diagram as the current measurement result is graphically displayed on the display unit 306 (S906).

  On the other hand, when the received light power of the selected plurality of verification points has changed by a predetermined amount or more (S903: YES), the utility pole stress evaluation apparatus 300 is specified by the plurality of verification points based on the amount of change. For one cross section of the electric pole 100, stress information indicating the degree and direction of the stress and position information indicating the position of the cross section are calculated (S906). Note that the utility pole stress evaluation apparatus 300 repeatedly executes the processes from S901 to S905 until the verification covering all the cross sections of the utility pole 100 is completed (S904: YES). When the verification covering all the cross sections of the utility pole 100 is completed (S904: YES), the utility pole stress evaluation apparatus 300 displays the stress information and position information of the utility pole 100 together with the level diagram measured this time. The graphic is displayed on the part 306 (S906).

  In the following, the processing from S901 to S905 shown in FIG. 9 is referred to as “electric pole stress evaluation processing”.

<Pole stress evaluation system>
=== System configuration ===
FIG. 10 is a diagram illustrating an embodiment in a case where the stress of a plurality of utility poles 100 constituting an electric power system is collectively evaluated in an electric power company office 400. That is, in the case shown in FIG. 10, both ends of the optical fiber cable 200 are respectively taken out from the outlets 110 of the plurality of utility poles 100, and each optical fiber cable 200 of the plurality of utility poles 100 is connected via the same type of optical fiber cable 202. This is a case where it is possible to collectively evaluate the stress of the plurality of utility poles 100 for each power system from the remote business office 400 by connecting the rosary.

FIG. 11 is a diagram showing a configuration of a utility pole stress evaluation system according to an embodiment of the present invention.
The utility pole stress evaluation system includes a plurality of power systems 1 to 3 in which optical fiber cables 200 in a plurality of utility poles 100 are connected together by the same type of optical fiber cable 202, a system selection unit 402, a utility pole stress evaluation apparatus 300, and an application server. (Hereinafter referred to as AP server) 403, database server (hereinafter referred to as DB server) 404, databases 405 to 407, Web server 410, local LAN 411, monitoring terminal 412, external LAN 500, external terminal 600, external trigger The apparatus 450, the anemometer 451, and the seismometer 452 are comprised.
The system selection unit 402 is an apparatus that sequentially selects a plurality of power systems 1 to 3 in accordance with an instruction from the AP server 403 via the utility pole stress evaluation apparatus 300.

  The utility pole stress evaluation apparatus 300 has been described with reference to FIGS. 8 and 9 as described above. However, the utility pole stress evaluation apparatus 300 according to the present embodiment is only shown in FIG. 3 in order to function as a client of the AP server 403. It is assumed that only the OTDR measurement process (S300 to S304) shown in FIG. Accordingly, it is assumed that the utility pole stress evaluation process (S900 to S905) illustrated in FIG. Moreover, the utility pole stress evaluation apparatus 300 controls the sequential selection of the power systems 1 to 3 in the system selection unit 402 in accordance with an instruction from the AP server 403.

  The AP server 403 is a server that is accessed from the monitoring terminal 412 or the external terminal 600 via a Web browser, and executes an application program related to the control of the entire utility pole stress evaluation system according to a predetermined schedule managed by the schedule management unit 4031. is there. Specifically, the AP server 403 performs a response to a request from a Web browser via the Web server 410, a connection process to the databases 405 to 407 via the DB server 404, and a plurality of related processes into one process. To manage transactions linked to The transaction management realizes a utility pole stress evaluation process in cooperation with the utility pole stress evaluation apparatus 300 that functions as a client.

The DB server 404 is a server that manages the databases 405 to 407 and responds to access requests to the databases 405 to 407 independently of the application program of the AP server 403.
The database 405 stores a reference level diagram as a reference for stress evaluation of the plurality of power poles 100 for each of the power systems 1 to 3 acquired by the power pole stress evaluation apparatus 300. The database 405 also stores a level diagram acquired at that time each time the application program of the AP server 403 is executed.
The database 406 shows facility information existing in the service target area of the office 400, in particular, identifiers (node numbers and the like) of the plurality of power poles 100 connected to each of the power systems 1 to 3, and connection relations between the power poles 100. Information, place name information (prefecture, city, ward, etc.) to which each power pole 100 belongs and geographical information (latitude, longitude, etc.) are stored.
The database 407 stores map information of the service target area of the office 400 and its surrounding area.

The Web server 410 stores information such as HTML documents and images independently of the application program of the AP server 403, and monitors the terminal 412 via the local LAN 411 or the external terminal 600 via the external LAN 500. In response to a request from the Web browser, the server transmits the stored information such as an HTML document or an image to the monitoring terminal 412 or the outside terminal 600.
The monitoring terminal 412 is installed with a Web browser and connected to the local LAN 411. In order to monitor the state of stress and the like of the plurality of utility poles 100 for each of the power systems 1 to 3, the clerk in the office 400 The terminal to use.
The outside terminal 600 is a terminal that is installed by a web browser and connected to the outside LAN 500, and is used by office workers of the office 500, related employees, and other unspecified persons.

  The external trigger device 450 executes the application program according to the steady schedule in the AP server 403, and when the wind speed exceeding the predetermined wind speed is observed by the anemometer 451 (storm), or the seismometer 452 has a predetermined seismic intensity. When a seismic intensity exceeding 1 is observed (at the time of an earthquake), a trigger signal is transmitted to the AP server 400, and as a result, the AP server 400 is caused to execute an application program.

=== System operation ===
FIG. 12 is an example of a flowchart illustrating a startup sequence of an application program related to control of the entire utility pole stress evaluation system, which is performed in the AP server 403.

The AP server 403 determines whether or not to receive a trigger signal from the external trigger device 450 (S120), and when no trigger signal is received (S120: NO), the schedule at the normal time (for example, one day) The application program starts to be executed (S121).
On the other hand, when the trigger signal is received (S120: YES), the AP server 403 identifies whether the trigger signal is based on the anemometer 451 or the seismometer 452 (S122).

  Here, when it is identified that the trigger signal is from the anemometer 451, the AP server 403 activates the schedule for a storm (for example, once per hour) with a higher execution frequency than the schedule for the steady state. Etc.), the execution of the application program is started (S123).

  In addition, when identifying that the trigger signal is from the seismometer 452, the AP server 403 activates the earthquake schedule (for example, immediately after an earthquake occurs, with a higher execution frequency than the storm schedule) In addition, the application program starts to be executed (S124).

  FIG. 13 is a flowchart of an application program related to the control of the entire utility pole stress evaluation system, which is executed in the AP server 403.

  First, the system is activated, that is, the execution of the application program is started according to the schedule at the normal time or the schedule at the time of storm or earthquake by the trigger signal from the external trigger device 450 (S130). At this time, the AP server 403 sequentially specifies the power systems 1 to 3 to be subjected to the utility pole stress evaluation.

  Next, the AP server 403 controls the power pole stress evaluation apparatus 300 as a client, so that for each of the power systems 1 to 3, and for each of the plurality of power poles 100 connected in a daisy chain in each of the power systems 1 to 3, The utility pole stress evaluation process from S900 to S905 shown in FIG. 9 is executed N times (S131, S132). As a result, the level diagrams shown in FIG. 5B and FIG. 7B are obtained N times for each utility pole 100.

  Next, the AP server 403 determines whether an event point at which the received light power changes by a predetermined amount or more appears in the level diagram for N times for each utility pole 100 in comparison with the reference level diagram stored in the database 405 in advance. Whether or not is identified (S133).

  Next, when the event point does not appear (S133: NO), the AP server 403 determines that the stress of the utility pole 100 to be evaluated is “normal” (S134). “Normal” means that the degree of normal stress of the utility pole 100 is high.

  On the other hand, when the event point has appeared (S133: YES), the event point has appeared in a level diagram for N times exceeding the frequency of predetermined M (M <N) times. (S135: YES), the stress of the utility pole 100 to be evaluated is determined as “abnormal” (S136). Further, when the event point has appeared with a frequency of less than M times (S135: NO), the stress of the utility pole 100 to be evaluated is determined as “Needs Attention” (S137). Note that “abnormal” indicates that the degree of normal stress of the utility pole 100 is low, and “caution” indicates that the degree of normal stress of the utility pole 100 is moderate.

  Next, the AP server 403 reads out the facility information related to the utility pole 100 stored in the database 406 and the map information stored in the database 407 via the DB server 404. Then, the AP server 403 associates the above-described facility information and map information with the stress determination result of the utility pole 100 that is the object of evaluation described above, and sends it to the monitoring terminal 412 and the outside terminal 600 via the Web server 410. Graphic display is performed (S138).

  FIG. 14 shows an example of a graphic display displayed on the monitoring terminal 412. According to the graphic display shown in FIG. 14, for the clerk in the office 400, the state of the stress of each power pole 100 connected to each of the power systems 1 to 3 is expressed as “normal”, “abnormal”, “ It can be clearly indicated in a color as “Caution required”. Accordingly, the clerk in the office 400 can grasp the crack status and fatigue status of each power pole 100 to be managed while being far away, and promptly inspect the worker for inspection and maintenance work. Can do.

  FIG. 15 shows an example of a graphic display displayed on the outside terminal 600. According to the graphic display shown in FIG. 15, the damage situation of an area having each power pole 100 determined as “abnormal” or “attention required” due to an earthquake or storm to an unspecified number of people is indicated as “abnormal” or It becomes possible to grasp by “coloring with caution”. If the area shown in FIG. 15 is clicked, the detailed stress state for each utility pole 100 shown in FIG. 14 in the area is displayed.

  Although the present embodiment has been described above, the above-described examples are for facilitating the understanding of the present invention, and are not intended to limit the present invention. The present invention can be changed / improved without departing from the spirit thereof, and the present invention includes equivalents thereof.

It is the figure which showed one Example when an evaluator goes to the spot and implements stress evaluation of a utility pole. It is a figure explaining the outline | summary of the loss test of the optical fiber cable using OTDR. It is a flowchart explaining the outline | summary of the loss test of the optical fiber cable using OTDR. FIG. 4A is a perspective view of a utility pole when a single continuous optical fiber cable is folded and disposed inside the utility pole, and FIG. 4B is a cross-sectional view of the utility pole in this case. FIG. 5A is a diagram showing a state of one section of the optical fiber cable shown in FIG. 4A and an acquired level diagram. FIG. 5B is a diagram showing a situation of one cross section when a side pressure is applied and a level diagram obtained in this case. FIG. 6A is a perspective view of a utility pole when a single continuous optical fiber cable is spirally arranged inside the utility pole, and FIG. 6B is a cross-sectional view of the utility pole in this case. . FIG. 7A is a diagram showing the situation of two cross sections of the optical fiber cable shown in FIG. 6A and the acquired level diagram. FIG. 7B is a diagram showing each situation of a cross section when a side pressure is applied and a cross section where no side pressure is applied, and a level diagram obtained in this case. It is the figure which showed the structure of the utility pole stress evaluation apparatus which concerns on one Embodiment of this invention. It is a flowchart which shows operation | movement of the utility pole stress evaluation apparatus which concerns on one Embodiment of this invention. It is a figure which shows one Embodiment in the case of evaluating collectively the stress of the several utility pole which comprises an electric power grid in the office of an electric power company collectively. It is a figure which shows the structure of the utility pole stress evaluation system which concerns on one Embodiment of this invention. It is a flowchart which shows the starting sequence of the application program implemented in AP server which concerns on one Embodiment of this invention. It is a flowchart of the application program implemented in AP server which concerns on one Embodiment of this invention. It is the figure which showed the graphic display displayed on the monitoring terminal which concerns on one Embodiment of this invention. It is the figure which showed the graphic display displayed on the outside terminal which concerns on one Embodiment of this invention.

Explanation of symbols

1, 2 and 3 Power system 100 Utility pole 101 Reinforcing bar 110 Outlet 200 Optical fiber cable 201 Optical fiber cable 300 Utility pole stress evaluation device 301 Laser diode 302 Optical coupler 303 Light receiving unit 304 Signal processing unit 305 Memory 306 Display unit 307 Interface 402 System selection Unit 403 Application server 4031 Schedule management unit 404 Database server 405 to 407 Database 410 Web server 411 Local LAN
412 Monitoring terminal 450 External trigger device 451 Anemometer 452 Seismometer 500 Outside LAN 600 Outside terminal 800 OTDR 810 Optical fiber cable

Claims (17)

A concrete pillar supporting the wire,
One continuous optical fiber cable disposed inside the concrete of the concrete pillar, in the longitudinal direction of the concrete pillar,
For a utility pole having an outlet for taking out one end of the optical fiber cable,
A light emitting unit that emits pulsed light that is incident from one end of the optical fiber cable extracted from the extraction port toward the other end; and
A light receiving unit that receives reflected light corresponding to the pulsed light between the one end and the other end and detects a light receiving power of the reflected light;
Obtaining a level diagram of the received light power with respect to the distance of the optical fiber cable based on the received light power and the time required from emission of the pulsed light to reception of the reflected light, and based on the acquired level diagram A signal processing unit for evaluating the stress of the concrete column;
The utility pole stress evaluation apparatus characterized by having. In order to reciprocate the longitudinal distance of the concrete pillar at least once, the optical fiber cable is folded and disposed inside the concrete,
The signal processing unit
For a plurality of locations of the optical fiber cable appearing for each cross section of the concrete column, evaluating the stress for each cross section of the concrete column based on the received light power on the acquired level diagram,
The utility pole stress evaluation apparatus according to claim 1. In order for the optical fiber cable to appear in at least three places in the cross section of the concrete pillar, the optical fiber cable is folded and disposed inside the concrete,
The signal processing unit
Based on the received power on the acquired level diagram for the plane identified by the three or more locations of the optical fiber cable that appears for each cross-section of the concrete column, for each cross-section of the concrete column Assessing stress,
The utility pole of Claim 2 characterized by these. The optical fiber cable is spirally arranged inside the concrete toward the longitudinal direction of the concrete pillar,
The signal processing unit
Evaluating the stress for each cross section of the concrete column based on the received light power on the acquired level diagram for multiple locations of the optical fiber cable that appear at different locations for each cross section of the concrete column,
The utility pole of Claim 2 characterized by these. A concrete column that supports the electric wire, a single continuous optical fiber cable disposed in the concrete of the concrete column in the longitudinal direction of the concrete column, and an outlet for taking out both ends of the optical fiber cable A power system in which a plurality of the optical fiber cables taken out from the outlets of the plurality of power poles are connected,
A light emitting unit that emits pulsed light from one end of the optical fiber cable connected in a daisy chain toward the other end, and reflected light corresponding to the pulsed light from the one end to the other end The light receiving unit that receives light and detects the light reception power of the reflected light, and the light reception with respect to the distance of the optical fiber cable based on the light reception power and the time required from the emission of the pulsed light to the reception of the reflected light A power pole stress evaluation apparatus having a signal processing unit for acquiring a power level diagram;
Based on the level diagram acquired by the utility pole stress evaluation device, an application server that collectively evaluates each stress of the plurality of utility poles that the power system has,
The utility pole stress evaluation system characterized by having. The application server is
Starts a series of processes related to the collective evaluation in cooperation with the utility pole stress evaluation device according to a first schedule at regular times or a second schedule at the time of a storm or earthquake set at a higher start frequency than the first schedule To do,
The utility pole stress evaluation system according to claim 5. The application server is
As a result of starting a series of processes related to the batch evaluation multiple times for the utility pole stress evaluation device, the level diagram is acquired for the multiple times,
Regarding the obtained multiple level diagram,
When an event point where the amount of change in the received light power exceeds a predetermined amount does not appear, it is determined that the degree of normality of the stress of the plurality of utility poles of the power system is high,
If the event point appears,
When the event point appears in the same place without exceeding the predetermined frequency, it is determined that the degree of normality of the stress of the utility pole corresponding to the event point is medium,
When the event point appears at the same location over a predetermined frequency, it is determined that the degree of normal stress of the utility pole corresponding to the event point is low,
The utility pole stress evaluation system according to claim 5 or 6. The plurality of utility poles of the power system are:
In order to reciprocate the longitudinal distance of the concrete pillar at least once, the optical fiber cable is folded and disposed inside the concrete,
The application server is
For a plurality of locations of the optical fiber cable appearing for each cross section of the concrete column, evaluating the stress for each cross section of the concrete column based on the received light power on the acquired level diagram,
The utility pole stress evaluation system according to claim 7. The plurality of utility poles of the power system are:
The optical fiber cable is folded and disposed inside the concrete so that the optical fiber cable appears in at least three places in the cross section of the concrete pillar,
The application server is
Based on the received power on the acquired level diagram for the plane identified by the three or more locations of the optical fiber cable that appears for each cross-section of the concrete column, for each cross-section of the concrete column Assessing stress,
The utility pole stress evaluation system according to claim 8, wherein: The plurality of utility poles of the power system are:
In the longitudinal direction of the concrete pillar, the optical fiber cable is spirally arranged inside the concrete,
The application server is
Evaluating the stress for each cross section of the concrete column based on the received light power on the acquired level diagram for multiple locations of the optical fiber cable that appear at different locations for each cross section of the concrete column,
The utility pole stress evaluation system according to claim 8, wherein: A concrete pillar supporting the wire,
One continuous optical fiber cable disposed inside the concrete of the concrete pillar, in the longitudinal direction of the concrete pillar,
For a utility pole having an outlet for taking out one end of the optical fiber cable,
Reflection according to the pulsed light from the one end to the other end as a result of incidence of pulsed light from one end of the optical fiber cable taken out from the takeout port toward the other end Detect the received light power of light,
Based on the light reception power and the time required from the emission of the pulsed light to the reception of the reflected light, obtain a level diagram of the light reception power with respect to the distance of the optical fiber cable;
Evaluating the stress of the concrete column based on the acquired level diagram;
Electric pole stress evaluation method characterized by this. A concrete pillar supporting the wire,
One continuous optical fiber cable disposed inside the concrete of the concrete pillar, in the longitudinal direction of the concrete pillar,
An outlet for taking out one end of the optical fiber cable;
A utility pole characterized by having.   13. The utility pole according to claim 12, wherein the optical fiber cable is folded and disposed inside the concrete so as to reciprocate the longitudinal distance of the concrete pillar at least once.   The electric pole according to claim 13, wherein the optical fiber cable is folded and disposed inside the concrete so that at least three or more of the optical fiber cables appear in a cross section of the concrete pillar.   The electric pole according to claim 13, wherein the optical fiber cable is spirally arranged inside the concrete in a longitudinal direction of the concrete pole.   The utility pole according to any one of claims 12 to 15, wherein the take-out port is opened with an inclination toward a ground plane on which the concrete pillar is laid. The utility pole according to any one of claims 12 to 16, wherein both ends of the optical fiber cable are taken out from the take-out port.

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