Power transmission line icing monitoring device based on distributed optical fibers

Abstract

A power transmission line icing monitoring device based on distributed optical fibers comprises distributed optical fiber sensors embedded in a power transmission conductor sheath. The distributed optical fiber sensor is connected with an optical fiber demodulator through an optical fiber patch cord; the optical fiber demodulator is used for collecting a Brillouin scattering light signal and analyzing strain and temperature data; the edge calculation module is in communication connection with the optical fiber demodulator, an icing thickness calculation model is arranged in the edge calculation module, and the edge calculation module is used for outputting an ice layer thickness value according to the strain variation delta epsilon and the temperature variation delta T; and the wireless communication module is connected with the edge calculation module, and sends an alarm signal to a monitoring center when the thickness value of the ice layer exceeds a threshold value. The power transmission line icing monitoring device based on the distributed optical fibers provided by the utility model can significantly improve the reliability and efficiency of icing monitoring.

Description

Technical Field

[0001] This utility model relates to the field of transmission line performance monitoring, and in particular to a transmission line icing monitoring device based on distributed optical fiber. Background Technology

[0002] With the continuous development of power systems and the acceleration of urbanization, the safety and stability of transmission lines are receiving increasing attention. As an important component of transmission lines, conductors play a crucial role in ensuring power supply and reducing accident risks through performance monitoring.

[0003] Currently, the performance of transmission line conductors is typically monitored through manual inspections or the installation of fixed monitoring equipment. For manual inspections, professional monitoring personnel need to periodically monitor the conductors along fixed routes. However, this method is prone to data errors due to human factors, making it difficult to guarantee the accuracy of the monitoring results.

[0004] Existing icing monitoring technologies have the following main drawbacks:

[0005] 1. Image monitoring method: Relies on cameras to capture the appearance of wires, which is susceptible to interference from rain, snow and fog, requires supplemental lighting at night, and has a false alarm rate of over 30% (see CN201810123456.7).

[0006] 2. Tension sensor method: The weight of ice accumulation is estimated by the change of wire tension, but it cannot locate the ice formation and is greatly affected by wind vibration (see CN201920987654.2).

[0007] 3. Manual inspection method: low efficiency, high cost, and unable to cope with sudden extreme weather. Utility Model Content

[0008] The technical problem to be solved by this utility model is to provide a transmission line icing monitoring device based on distributed optical fiber, which solves the problems that traditional image monitoring methods are easily affected by rain and snow and that tension sensor methods cannot locate the icing position, further reduces the installation and maintenance costs of traditional transmission line icing monitoring methods, and improves the accuracy of the final results of transmission line icing monitoring.

[0009] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows:

[0010] A distributed optical fiber-based transmission line icing monitoring device includes a distributed optical fiber sensor embedded in the sheath of the transmission conductor; the distributed optical fiber sensor is connected to an optical fiber demodulator via an optical fiber patch cord, the optical fiber demodulator is used to collect Brillouin scattered light signals and analyze strain and temperature data; an edge computing module is communicatively connected to the optical fiber demodulator, the edge computing module has a built-in icing thickness calculation model, and is used to output the ice layer thickness value based on the strain change Δε and the temperature change ΔT; a wireless communication module is connected to the edge computing module, and sends an alarm signal to the monitoring center when the ice layer thickness value exceeds a threshold.

[0011] The distributed optical fiber sensor is spirally wound or arranged in parallel along the axial direction of the power transmission line.

[0012] The distributed optical fiber sensor is covered with an anti-ultraviolet coating with a thickness of 0.2-0.5 mm.

[0013] The icing thickness calculation model of the edge computing module satisfies the following formula:

[0014] ;

[0015] In the formula: Indicates the thickness of the ice layer. , For calibration coefficients, It represents the change in strain. This is the environmental compensation constant.

[0016] The wireless communication module adopts the LoRa protocol, and the transmit power is adjustable in the range of 14-20dBm.

[0017] This utility model provides a transmission line icing monitoring device based on distributed optical fiber, which has the following technical effects:

[0018] 1) Strong anti-interference capability: Fiber optic sensing is not affected by electromagnetic fields or rain and fog, and the false alarm rate is reduced to less than 5% compared with traditional image methods;

[0019] 2) Precise positioning: 1m spatial resolution can identify the location of local icing on the conductor (such as the center of the span or the section near the tower).

[0020] 3) Low power consumption operation: It adopts event-triggered communication, with standby power consumption of <1W, which is suitable for solar power supply scenarios. Attached Figure Description

[0021] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0022] Figure 1 This is a connection diagram of the present invention.

[0023] Figure 2 This is a flowchart of the data processing in this utility model.

[0024] In the diagram: 1. Power transmission line; 2. Fiber optic sensor; 3. Demodulator; 4. Fiber optic patch cord; 5. Edge module; 6. Communication module. Detailed Implementation

[0025] like Figure 1-2 As shown, a distributed optical fiber-based transmission line icing monitoring device includes a distributed optical fiber sensor 2 embedded in the outer sheath of the transmission conductor 1. The distributed optical fiber sensor 2 is used to sense strain and temperature changes caused by icing in real time. There is at least one distributed optical fiber sensor 2, which can be spirally wound or arranged parallel to the axis of the transmission conductor 1. An optical fiber demodulator 3 is connected to the distributed optical fiber sensor 2 via an optical fiber jumper 4. The optical fiber demodulator 3 is used to collect Brillouin scattered light signals and analyze strain and temperature data (strain change Δε and temperature change ΔT). An edge computing module 5 is communicatively connected to the optical fiber demodulator 3. The edge computing module 5 has a built-in icing thickness calculation model and is used to output the ice thickness value based on the strain change Δε and temperature change ΔT. A wireless communication module 6 is connected to the edge computing module 5. The wireless communication module 6 only sends an alarm signal to the monitoring center when the ice thickness exceeds a threshold.

[0026] When icing causes deformation in the transmission lines, the optical fiber undergoes a micro-bend. Signals are collected by the fiber optic demodulator 3. Since the Brillouin dispersion frequency shift Δν is linearly related to the strain Δε, the strain-temperature data can be mapped to the ice thickness value using the edge computing module. The demodulator collects data every 5 minutes. The edge computing module uses a temperature compensation algorithm to eliminate environmental interference. When the ice thickness exceeds a preset threshold (e.g., 5mm), the LoRa module is triggered to send an alert to the monitoring platform.

[0027] Preferably, the distributed optical fiber sensor 2 is coated with an anti-ultraviolet coating with a thickness of 0.2-0.5 mm. This has the advantage of protecting the optical fiber sensor.

[0028] Preferably, the icing thickness calculation model of the edge computing module 5 satisfies the formula:

[0029]

[0030] in, , For calibration coefficients, This is an environmental compensation constant, the coefficient of which was determined through laboratory icing simulation experiments. Indicates the thickness of ice accretion on transmission lines. This represents the amount of strain change in the optical fiber. ;

[0031] Preferably, the wireless communication module 6 adopts the LoRa protocol, and the transmit power is adjustable within a range of 14-20 dBm. The advantages are that it enables stable long-distance communication and allows for flexible adjustment of power consumption to adapt to solar power supply.

[0032] To achieve the above objectives, the structural design adopted in this invention is as follows:

[0033] 1. A distributed optical fiber sensor 2 (FISO FOS-N) is pre-embedded inside the outer insulating sheath of the transmission conductor 1 to avoid electromagnetic interference and achieve full line coverage;

[0034] 2. The fiber optic demodulator 3 uses a Brillouin optical time domain reflectometer (BOTDR) with a spatial resolution of 1m and a strain measurement accuracy of ±10με;

[0035] 3. Edge computing module 5 integrates lightweight machine learning models (such as XGBoost) to map strain-temperature data to ice thickness values.

[0036] Example 1:

[0037] Icing was simulated in an artificial climate chamber at -10℃. The specification of transmission line 1 was LGJ-400 / 35.

[0038] When the ice thickness reaches 8mm, the output value of this device is 7.9mm (error 1.25%), while the error of traditional tension sensors reaches 12%.

[0039] After 72 hours of continuous operation, the average power consumption is 1.8W (supported by solar panels).

[0040] Example 2:

[0041] This device was installed on a snow-covered route at an altitude of 3000m, and compared with the records of manual inspections during the same period:

[0042] This device successfully issued warnings for 3 icing exceedance events and had 0 false alarms.

[0043] The traditional camera system reported 7 false alarms (due to snow and fog interference) and 1 missed alarm.

Claims

1. A distributed fiber based power line icing monitoring device, characterized by: The system includes a distributed optical fiber sensor (2) embedded in the sheath of the transmission conductor (1); the distributed optical fiber sensor (2) is connected to an optical fiber demodulator (3) via an optical fiber jumper (4); the optical fiber demodulator (3) is used to collect Brillouin scattering light signals and analyze strain and temperature data; the edge computing module (5) is connected to the optical fiber demodulator (3); the edge computing module (5) has a built-in ice thickness calculation model and is used to output the ice thickness value according to the strain change Δε and the temperature change ΔT; the wireless communication module (6) is connected to the edge computing module (5) and sends an alarm signal to the monitoring center when the ice thickness value exceeds the threshold.

2. The distributed fiber based power line icing monitoring device of claim 1, wherein: The distributed optical fiber sensor (2) is spirally wound or arranged in parallel along the axial direction of the power transmission line (1).

3. The distributed fiber based power line icing monitoring device of claim 2, wherein: The distributed optical fiber sensor (2) is covered with an anti-ultraviolet coating with a thickness of 0.2-0.5 mm.

4. The transmission line icing monitoring device based on distributed optical fiber according to claim 1, characterized in that: The wireless communication module (6) adopts the LoRa protocol, and the transmit power is adjustable in the range of 14-20dBm.

Images