Monitoring and early warning device for power transmission line

Abstract

The utility model discloses a monitoring and early warning device for a power transmission line, which belongs to the technical field of monitoring equipment and comprises a mounting frame, a stress monitoring structure and an icing detection module, the mounting frame is mounted on a tower, a support frame is mounted on the surface of the mounting frame, the stress monitoring structure is assembled on the support frame on the upper side, and the icing detection module is mounted on the mounting frame. According to the utility model, a stress monitoring structure is designed, the stress change of the power transmission line can be sensed through the deformation of the thin pipe and the measurement of the strain gauges, the high-precision and multi-dimensional monitoring of the power transmission line is realized in cooperation with the monitoring of various sensors, and the icing detection module is also designed, so that the monitoring accuracy of the power transmission line is improved. The temperature and the ice load strain can be separated through the difference of thermal expansion numbers of the double-ring structure in combination with the wavelength offset of the fiber bragg grating, the thickness and the density of an ice layer are obtained, in addition, different ice types can be captured through the difference of adhesive force of the ice collecting groove, ice type recognition is achieved, and more accurate and more effective icing detection is achieved.

Description

TECHNICAL FIELD

[0001] The utility model belongs to monitoring equipment technical field, and particularly provide a kind of monitoring and early warning device for transmission line. BACKGROUND

[0002] With the rapid development of power system, the safe operation of transmission line faces severe challenges, icing, mechanical stress, vibration and other problems seriously threaten the stability of power grid. The existing line stress detection is generally single, without paying attention to the stress change caused by temperature change, so that the measurement result is not accurate enough. And icing monitoring generally does not obtain ice layer density, distribution and other parameters, which also affects the monitoring result. Traditional manual inspection relies on visual inspection and periodic preventive test, and has problems such as low efficiency, incomplete coverage and inability to real-time early warning, which is difficult to meet the demand of modern power grid for high reliability. Therefore, a device capable of effectively detecting the stress change of transmission line and detecting the icing condition and warning the icing hazard is needed. SUMMARY

[0003] To solve the above problems, the utility model provides a kind of monitoring and early warning device for transmission line.

[0004] To achieve the above purpose, the utility model adopts the technical scheme of a kind of monitoring and early warning device for transmission line, including mounting frame, stress monitoring structure and icing detection module, the mounting frame is installed on the tower, the surface of the mounting frame is provided with support frame, the stress monitoring structure is assembled on the upper side support frame, the icing detection module is assembled on two support frames.

[0005] The stress monitoring structure includes thin pipe and clamping plate, the thin pipe is half cylindrical structure, the clamping plate is U-shaped plate structure, two thin pipes are spliced and installed on the surface of transmission line, two clamping plates are assembled on the two ends of thin pipe, and the clamping plate is assembled on the upper side support frame, the inner surface of the thin pipe is provided with insulating layer, the inner wall of the insulating layer is uniformly fixed and installed with strain gauge, the outer surface of the thin pipe is fixedly installed with fixed edge plate, two thin pipes are spliced and installed by fixed edge plate and bolt nut.

[0006] Further, the inner wall of the insulating layer is equipped with micro temperature sensor, acceleration sensor, optical sensor and humidity sensor.

[0007] Further, the cross section of the clamping plate is symmetrically provided with round hole, the round hole is inserted with clamping bolt, two clamping plates are clamped and fixed to thin pipe by clamping bolt and nut, and the inner surface of the clamping plate is fixedly installed with temperature sensor.

[0008] Further, the inner end face of the clamping plate is provided with limiting groove, and the outer surface of the thin pipe is fixedly installed with limiting block matched with the limiting groove.

[0009] Further, the ice-coating detection module comprises a hanger, an ice-coating monitoring assembly, a connecting rod and a laser monitoring assembly, the hanger is assembled on the upper support frame, the lower end of the hanger is provided with the ice-coating monitoring assembly through the connecting rod, and the laser monitoring assembly is assembled on the lower support frame and located directly below the ice-coating monitoring assembly.

[0010] Further, the hanger comprises a mounting frame and two clamping blocks, the two clamping blocks are arranged in the mounting frame, and the power transmission line is located between the two clamping blocks, the inner end surface of the clamping block is provided with clamping teeth, the upper and lower surfaces of the mounting frame are provided with threaded holes, the threaded holes are screwed with locking bolts, the inner end of the locking bolt is rotatably provided with a pad plate, the pad plate is attached to the outer end surface of the clamping block, and the lower surface of the mounting frame is fixedly provided with a fixing ring, and one end of the connecting rod is fixed to the fixing ring.

[0011] Further, the ice-coating monitoring assembly comprises an outer ring and an inner ring, and the inner ring is located inside the outer ring, the outer surface of the outer ring is provided with an ice collection groove, the upper end surface of the outer ring is uniformly fixedly provided with a lifting ring, and the other end of the connecting rod is fixed to the lifting ring, the outer surface of the inner ring is provided with a spiral groove, the spiral groove is provided with a fiber grating, and the outer ring and the inner ring are provided with a spring sheet and a buffer pad.

[0012] Further, the outer ring is made of aluminum alloy, and the inner ring is made of nickel-titanium memory alloy, the ice collection groove is a three-stage stepped groove, and the three-stage stepped groove comprises a first-stage groove, a second-stage groove and a third-stage groove, and the depth and the roughness of the groove bottom of the first-stage groove, the second-stage groove and the third-stage groove increase in turn.

[0013] Further, the laser monitoring assembly comprises a bottom plate, a rotary stepping motor, a rotary platform and a laser, the bottom plate is fixedly installed on the lower support frame, the rotary stepping motor is fixedly installed on the bottom plate, the rotary platform is fixedly installed on the output end of the rotary stepping motor, three lasers are uniformly fixedly installed on the outer periphery of the upper surface of the rotary platform, and the output end of the laser faces the ice collection groove.

[0014] The beneficial effects of the utility model are as follows:

[0015] The stress monitoring structure can perceive the stress change of the power transmission line through the deformation of the thin pipe and the measurement of the strain gauge, can adjust the installation position according to actual needs, obviously improves the stress monitoring precision, and is additionally provided with a temperature sensor, can correct the deformation error caused by the thermal expansion and cold contraction of the material in real time, and further improves the stress monitoring precision.

[0016] The stress monitoring structure further comprises a miniature temperature sensor, an acceleration sensor, an optical sensor and a humidity sensor, through the monitoring of the multiple sensors, high-precision and multiple-dimension monitoring of the power transmission line is realized, and the monitoring range and precision of the power transmission line are improved.

[0017] The utility model discloses an icing detection module, simulate, detect and early warning to the icing condition of power transmission line, through the cooperation of icing monitoring subassembly and laser monitoring subassembly, can measure the icing thickness and peeling information of different ice type, and then complete the prediction and early warning of the influence of icing to power transmission line, realize more accurate icing detection. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 It is the schematic drawing of the utility model.

[0019] Figure 2 It is one of the three -dimensional schematic drawing of the stress monitoring structure of the utility model.

[0020] Figure 3 It is the second three -dimensional schematic drawing of the stress monitoring structure of the utility model.

[0021] Figure 4 It is the left view of the stress monitoring structure of the utility model.

[0022] Figure 5 It is the front view of the stress monitoring structure of the utility model.

[0023] Figure 6 It is the front view of the utility model hanger.

[0024] Figure 7 It is the front view of the utility model icing monitoring subassembly.

[0025] Figure 8 It is the three -dimensional schematic drawing of the utility model icing monitoring subassembly.

[0026] Figure 9 It is the three -dimensional schematic drawing of the utility model inner ring.

[0027] Figure 10 It is the three -dimensional schematic drawing of the utility model laser monitoring subassembly.

[0028] Figure 11 It is the front view of the utility model laser monitoring subassembly.

[0029] The reference signs include: 1, mounting frame, 2, stress monitoring structure, 21, thin pipe, 211, insulation layer, 212, strain gauge, 213, fixed edge plate, 214, limiting block, 22, clamping plate, 221, clamping bolt, 222, temperature sensor, 3, hanger, 31, mounting frame, 32, clamping block, 33, locking bolt, 34, backing plate, 4, icing monitoring assembly, 41, outer ring, 411, ice collection groove, 412, lifting ring, 42, inner ring, 421, fiber grating, 43, spring plate, 44, buffer pad, 5, connecting rod, 6, laser monitoring assembly, 61, bottom plate, 62, rotary stepper motor, 63, rotary platform, 64, laser. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the utility model.

[0031] Reference Figures 1 to 11 A monitoring and early warning device for a power transmission line, comprising a mounting frame 1, a stress monitoring structure 2 and an icing detection module, the mounting frame 1 is installed on a tower, a support frame is installed on the surface of the mounting frame 1, the stress monitoring structure 2 is assembled on the upper support frame, and the icing detection module is assembled on the two support frames.

[0032] The stress monitoring structure 2 is used for monitoring the stress of the power transmission line.

[0033] The icing detection module is used for detecting the ice thickness, density and type of the local environment.

[0034] A control module can be arranged on the support frame and electrically connected with the stress monitoring structure 2 and the icing detection module, so as to control and collect data, and the control module can be connected with a workbench through wireless signals.

[0035] As shown in Figures 2 to 5 The stress monitoring structure 2 comprises thin pipes 21 and clamping plates 22, the thin pipes 21 are semi-cylindrical tube structures, the clamping plates 22 are U-shaped plate structures, two thin pipes 21 are spliced and installed on the surface of the power transmission line, two clamping plates 22 are assembled at the two ends of the thin pipes, and the clamping plates 22 are assembled on the upper support frame, the inner surface of the thin pipe 21 is provided with an insulation layer 211, the inner wall of the insulation layer 211 is uniformly and fixedly provided with a strain gauge 212, the outer surface of the thin pipe 21 is fixedly provided with a fixed edge plate 213, and two thin pipes 21 are spliced and installed through the fixed edge plate 213 and a bolt and a nut.

[0036] The thin tube 21 is a titanium alloy tube, and two thin tubes 21 form a pipeline structure, and the power transmission line passes through the pipeline structure.

[0037] The U-shaped opening of the clamping plate 22 allows the power transmission line to pass through, and an arc-shaped pad plate is installed inside the U-shaped opening of the clamping plate 22, and the inner diameter of the arc-shaped pad plate is slightly smaller than the diameter of the power transmission line, which is used to assist in clamping and fixing the power transmission line, so that the strain gauge 212 in the thin tube 21 can perform more accurate stress measurement.

[0038] Specifically, the inner wall of the insulation layer 211 is equipped with a micro temperature sensor, an acceleration sensor, an optical sensor, and a humidity sensor.

[0039] The insulation layer 211 is a ceramic fiber insulation layer.

[0040] The strain gauge 212 is provided in four groups, each group having four strain gauges 212, and the included angle between adjacent two strain gauges 212 is 90 degrees, covering the stress concentration area in the thin tube 21.

[0041] The strain gauge 212 base is made of 3J01 elastic alloy, which matches the thermal expansion coefficient of the titanium alloy thin tube 21, and reduces the temperature drift error.

[0042] The fixed edge plates 213 of the two thin tubes 21 are spliced and fixed by bolts and nuts, which splice the two thin tubes 21 into a pipeline structure, and at the same time make the strain gauge 212 clamp the power transmission line, which can detect the deformation of the power transmission line.

[0043] The strain gauge 212, the micro temperature sensor, the acceleration sensor, the optical sensor, and the humidity sensor are electrically connected to the control module.

[0044] The micro temperature sensor is arranged between the thin tube 21 and the power transmission line, and can monitor the temperature and temperature rise in real time. The micro temperature sensor adopts an anti-electromagnetic interference design.

[0045] In addition, in actual application, optical fibers can be laid on the surface of the thin tube 21 to analyze the temperature distribution through light signal reflection, realizing high-precision and long-distance temperature monitoring.

[0046] The acceleration sensor is used to collect the vibration spectrum of the power transmission line, and combined with AI algorithm to identify abnormal vibration mode and give early warning of potential mechanical failure.

[0047] The optical sensor monitors the light energy loss near the installation point, calculates the contamination (salt density, ash density) on the surface of the power transmission line, and dynamically evaluates the insulation performance.

[0048] The humidity sensor monitors the humidity of the micro environment at the installation site to prevent electrochemical corrosion or condensation from causing insulation degradation.

[0049] Through the above-mentioned multiple monitoring methods, the transmission lines can be perceived with high precision and in multiple dimensions, improving the ability to identify potential hazards in the early stages and enabling the device to have an early warning function.

[0050] If strain gauge 212 detects that the deformation of the transmission line exceeds the threshold for 3 consecutive seconds, a level 1 warning is triggered.

[0051] Specifically, such as Figures 2 to 5 As shown, the cross-section of the clamping plate 22 is symmetrically provided with circular holes, and clamping bolts 221 are inserted into the circular holes. The two clamping plates 22 clamp and fix the thin tube by clamping bolts 221 and nuts. Temperature sensor 222 is fixedly installed on the inner surface of the clamping plate 22.

[0052] Temperature sensor 222 is used to detect ambient temperature in real time and plays a role in eliminating the interference of environmental thermal expansion and contraction when stress testing power transmission lines.

[0053] Specifically, such as Figures 2 to 5 As shown, a limiting groove is provided on the inner end face of the clamping plate 22, and a limiting block 214 matching the limiting groove is fixedly installed on the outer surface of the thin tube 21.

[0054] The position of the thin tube 21 within the clamping plate 22 is limited by the cooperation of the limiting groove and the limiting block 214.

[0055] Specifically, such as Figure 1 As shown, the icing detection module includes a hanger 3, an icing monitoring component 4, a connecting rod 5, and a laser monitoring component 6. The hanger 3 is mounted on the upper support frame, and the lower end of the hanger 3 is equipped with the icing monitoring component 4 via the connecting rod 5. The laser monitoring component 6 is mounted on the lower support frame, and the laser monitoring component 6 is located directly below the icing monitoring component 4.

[0056] Hanger 3 is used to hang the icing monitoring component 4.

[0057] The icing monitoring component 4 is used to generate an ice layer on the surface. It and the laser monitoring component 6 can detect the ice layer and obtain information such as ice thickness, density, and ice type, so as to more accurately determine the icing status of the transmission line and provide data support for subsequent maintenance and replacement.

[0058] Specifically, such as Figure 6 As shown, the hanger 3 includes a mounting frame 31 and clamping blocks 32. Two clamping blocks 32 are set inside the mounting frame 31, and the power transmission line is located between the two clamping blocks 32. The inner end face of the clamping block 32 is provided with clamping teeth. The upper and lower surfaces of the mounting frame 31 are provided with threaded holes. Locking bolts 33 are screwed into the threaded holes. The inner end of the locking bolt 33 is rotatably fitted with a pad 34, and the pad 34 is attached to the outer end face of the clamping block 32. A fixing ring is fixedly installed on the lower surface of the mounting frame 31, and one end of the connecting rod 5 is fixed to the fixing ring.

[0059] The mounting frame 31 is sleeved on the power transmission line to assist in positioning the position of the hanger 3.

[0060] In actual application, the hanger can not be provided with the mounting frame 31 and the clamping block 32, and only the fixing ring is provided to connect the ice monitoring assembly 4.

[0061] Specifically, as shown in Figures 7 to 9 , the ice monitoring assembly 4 comprises an outer ring 41 and an inner ring 42, the inner ring 42 is located inside the outer ring 41, the outer surface of the outer ring 41 is provided with an ice collection groove 411, the upper end surface of the outer ring 41 is uniformly fixedly provided with a lifting ring 412, and the other end of the connecting rod 5 is fixed on the lifting ring 412, the outer surface of the inner ring 42 is provided with a spiral groove, the spiral groove is assembled with a fiber grating 421, and the spring sheet 43 and the buffer pad 44 are assembled between the outer ring 41 and the inner ring 42.

[0062] Specifically, as shown in Figure 7 and Figure 8 , the outer ring 41 is made of aluminum alloy, the inner ring 42 is made of nickel-titanium memory alloy, the ice collection groove 411 is a three-stage stepped groove, and the three-stage stepped groove comprises a first-stage groove, a second-stage groove and a third-stage groove, and the depth and the roughness of the groove bottom of the first-stage groove, the second-stage groove and the third-stage groove increase in turn.

[0063] The expansion coefficients of the outer ring 41 and the inner ring 42 are different, and ice can be generated in the ice collection groove 411, when the temperature decreases and ice is generated in the ice collection groove 411, the spring sheet 43 will be deformed under the pressure, at this time, the fiber grating 421 can obtain corresponding data under the influence of mechanical strain.

[0064] The axial length of the spiral groove is slightly larger than the axial length of the ice collection groove 411.

[0065] The grating period of the fiber grating 421 will be affected by mechanical strain, and the fiber grating 421 will also be affected by thermal expansion and thermo-optic effect; in the spiral groove, the fiber grating 421 is divided into six groups, and three gratings are arranged in each group.

[0066] For the first-stage groove, the second-stage groove and the third-stage groove, the depth and the roughness of the groove bottom need to be set:

[0067] In this embodiment, the depth of the first-stage groove is 3mm, the roughness of the groove bottom is 12.5μm, the target ice type is frost ice, the characteristics are low density and weak adhesion, easy to form under low temperature and breeze conditions, increase the static load of the power transmission line, and may cause the sag to exceed the standard, and the ice layer peeling strength is 0.18MPa, and the corresponding wind speed threshold is 8m / s;

[0068] The second level groove has a depth of 5mm, a groove bottom roughness of 25μm, and a target ice type of wet snow ice, which is characterized by medium density and strong adhesion, easy to cause transmission line galloping and interphase short circuit, and an ice layer peeling strength of 0.45MPa, corresponding to a wind speed threshold of 15m / s;

[0069] The third level groove has a depth of 8mm and a groove bottom roughness of 50μm. The target ice type is mixed ice, which is characterized by high density, strong adhesion, and large mechanical strength, and can cause transmission line overload fracture or tower overturning, with an ice layer peeling strength of 0.75MPa, corresponding to a wind speed threshold of 25m / s.

[0070] When the environmental wind speed exceeds the wind speed threshold, i.e., the ice layer in the corresponding ice collection groove 411 is peeled off, the spring sheet 43 is elastically deformed, and the fiber grating 421 is prewarned under the influence of mechanical strain, at this time, it indicates that the dynamic load borne by the transmission line has approached the safety threshold.

[0071] When the temperature rises suddenly, causing the ice layer to melt and peel off, the strain change will also cause the fiber grating 421 to prewarn, which may cause the transmission line to jump and cause instantaneous mechanical impact.

[0072] The outer ring 41 and the inner ring 42 are connected by a high-stiffness spring sheet 43, which can effectively improve the strain transmission efficiency, and further make the measurement of the fiber grating 421 more accurate, and at the same time, cooperate with the detection of the laser monitoring assembly 6, which can determine which level the ice layer peeled off from the ice collection groove 411 is located.

[0073] Through the cooperation of the laser monitoring assembly 6 and the fiber grating 421, the ice thickness and peeling condition of different ice types in the ice collection groove 411 are detected, and then the ice condition and hazard condition on the transmission line are prewarned.

[0074] Specifically, as shown in Figure 10 and Figure 11 The laser monitoring assembly 6 includes a bottom plate 61, a rotary stepping motor 62, a rotary platform 63, and three lasers 64. The bottom plate 61 is fixedly installed on the lower support frame, the rotary stepping motor 62 is fixedly installed on the bottom plate 61, the rotary platform 63 is fixedly installed on the output end of the rotary stepping motor 62, and the three lasers 64 are uniformly fixedly installed on the outer periphery of the upper surface of the rotary platform 63, and the output end of the laser 64 faces the ice collection groove 411.

[0075] The output laser beam of the laser 64 has an elevation angle of 60° with the vertical direction, and directly irradiates the surface of the ice collection groove 411 for measuring the ice thickness. During the measurement process, the rotary platform 63 is controlled to rotate one revolution, and the three lasers 64 can obtain multiple measurement data in the ice collection groove 411, and then the ice thickness is calculated by weighted average.

[0076] Through the cooperation detection of the fiber grating 421 and the laser monitoring assembly 6, the goals of early warning serious icing, greatly shortening the repair response time and reducing the maintenance cost can be achieved.

[0077] The above merely describes the preferred embodiments of the present application, and for those skilled in the art, many changes can be made to the specific embodiments and application ranges according to the idea of the present application, as long as the changes do not deviate from the concept of the present application, and all the changes shall fall within the protection scope of the present application.

Claims

1. A monitoring and warning device for power transmission lines, characterized in that: The utility model provides an ice detection module and stress monitoring structure for transmission line, including mounting frame, stress monitoring structure and icing detection module, mounting frame is installed on the tower, the surface of mounting frame is installed with support frame, stress monitoring structure is assembled on upside support frame, icing detection module is assembled on two support frames; The stress monitoring structure includes thin pipes and clamping plates, the thin pipes are semi-cylindrical tube structures, the clamping plates are U-shaped plate structures, two thin pipes are spliced and installed on the surface of the transmission line, two clamping plates are assembled on both ends of the thin pipes, and the clamping plates are assembled on the upside support frame, the inner surface of the thin pipes is provided with an insulating layer, strain gauges are uniformly fixed and installed on the inner wall of the insulating layer, fixed edge plates are fixedly installed on the outer surface of the thin pipes, and two thin pipes are spliced and installed through the fixed edge plates and bolts and nuts.

2. The monitoring and early warning device for power transmission lines according to claim 1, characterized in that: The inner wall of the insulating layer is assembled with a miniature temperature sensor, an acceleration sensor, an optical sensor and a humidity sensor.

3. The monitoring and warning device for power transmission lines according to claim 1, characterized in that: The cross section of the clamping plate is symmetrically provided with a circular hole, a clamping bolt is inserted into the circular hole, and two clamping plates are clamped and fixed on the thin pipe through the clamping bolt and a nut.

4. The monitoring and warning device for power transmission lines according to claim 1, characterized in that: The inner end surface of the clamping plate is provided with a limiting groove, and the outer surface of the thin pipe is fixedly provided with a limiting block matched with the limiting groove.

5. The monitoring and warning device for power transmission lines according to claim 1, characterized in that: The icing detection module includes a hanger, an icing monitoring assembly, a connecting rod and a laser monitoring assembly, the hanger is assembled on the upside support frame, the icing monitoring assembly is installed on the lower end of the hanger through the connecting rod, the laser monitoring assembly is assembled on the downside support frame, and the laser monitoring assembly is located directly below the icing monitoring assembly.

6. The monitoring and warning device for power transmission lines according to claim 5, characterized in that: The hanger includes a mounting frame and clamping blocks, two clamping blocks are arranged in the mounting frame, and the transmission line is located between the two clamping blocks, the inner end surface of the clamping block is provided with clamping teeth, screw holes are formed in the upper and lower surfaces of the mounting frame, locking bolts are screwed in the screw holes, a pad plate is rotatably assembled on the inner end of the locking bolt, and the pad plate is attached to the outer end surface of the clamping block, a fixing ring is fixedly installed on the lower surface of the mounting frame, and one end of the connecting rod is fixed on the fixing ring.

7. The monitoring and warning device for power transmission lines according to claim 5, characterized in that: The icing monitoring assembly includes an outer ring and an inner ring, and the inner ring is located inside the outer ring, the outer surface of the outer ring is provided with an ice collecting groove, the upper end surface of the outer ring is uniformly fixedly provided with eyelets, the other end of the connecting rod is fixed on the eyelets, the outer surface of the inner ring is provided with a spiral groove, an optical fiber grating is assembled in the spiral groove, and a spring sheet and a buffer pad are assembled between the outer ring and the inner ring.

8. The monitoring and warning device for power transmission lines according to claim 7, characterized in that: The outer ring is made of aluminum alloy, and the inner ring is made of nickel-titanium memory alloy, the ice collecting groove is a three-stage stepped groove, and the three-stage stepped groove includes a first-stage groove, a second-stage groove and a third-stage groove, the depths and the roughnesses of the groove bottoms of the first-stage groove, the second-stage groove and the third-stage groove increase in sequence.

9. The monitoring and warning device for power transmission lines according to claim 7, characterized in that: The laser monitoring assembly includes a base plate, a rotary stepping motor, a rotary platform and lasers, the base plate is fixedly installed on the downside support frame, the rotary stepping motor is fixedly installed on the base plate, the rotary platform is fixedly installed on the output end of the rotary stepping motor, three lasers are uniformly fixedly installed on the outer periphery of the upper surface of the rotary platform, and the output ends of the lasers face the ice collecting groove.

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