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A potential fatal problem for electrical power delivery through power lines in Northern countries is when snow or ice accumulates on electrical insulators. This could lead to snow or ice-induced outages and voltage collapse, causing huge economic loss. Further, large swing angles due to wind may cause short circuits. This paper presents a novel vid...
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... b is 0.00597, and c is 0.01135. The quantitative detection model can be obtained by substituting a, b, and c into (3) and (4), as shown in (8) and (9). ...
Long-term cold cause ice to build on transmission lines, making it risky for the electrical infrastructure to work. There is a lack of methods for quantitative detection of ice on overhead transmission line insulators. In this paper, we built a quantitative detection system for natural ice covering of composite insulators by quasi-distributed fiber Bragg gratings and implanted six optical fibers with 13 quasi-distributed fiber Bragg gratings (FBGs) each into the interface of a 110 kV composite insulator. Natural ice cover detection tests were done at an ice observation station in Guizhou, China, to study the types and mechanisms of ice cover. A method for quantitative detection of composite insulator ice cover using a quantitative ice cover detection model is proposed. The results showed that four types of ice cover appeared on the composite insulator of the ice observation station in turn. The average absolute error of the quantitative detection method proposed in this paper is 9.7g and the average relative error is 20.6% for the field detection of 42.5g∼60.4g of umbrella skirt glaze icing load, and the average absolute error is 24.6g and the average relative error is 13.2% for the average 186.2g of umbrella skirt mixed ice load.
... At present, the optical image method is the primary tool for ice detection on insulators. Cameras are installed on towers of transmission lines to capture ice images of insulators and assess the icing degree of insulators through image analysis [4][5][6][7][8]. ...
The electrical performance of transmission line insulators will decrease dramatically under ice‐covered conditions, and ice flashover may occur under operating voltage. There is no direct and effective monitoring method for ice cover on insulators of transmission lines. In this paper, the interface quasi‐distributed fibre Bragg grating (FBG) is used to study the positioning detection of glaze icing loads on composite insulators, and a mechanical lever model of single glaze icing load on single umbrella detection with three FBGs is established. Based on this model, a multi‐glaze location detection method on multiple umbrella skirts is proposed. Six optical fibres with 13 quasi‐distributed FBGs each are implanted into the interface of a 110 kV composite insulator. The minimum load test of FBG for detecting glaze icing load, the FBG axial/circumferential sensing rule test for the glaze, and the weight simulation test and laboratory icing verification test for multi‐glazes on multi‐umbrellas location detection method are carried out. The results show that the positioning of glaze simulated by weights is accurate, and the positioning of icing in the laboratory is basically correct.
... In this context, to detect the swing angles and snow coverage of high voltage insulators, an experiment was conducted in [15] based on recorded videos of 420 kV power transmission lines. A novel video inspection technique conducted, and with implementation of hybrid techniques, the fault detection rates for good and poor quality images reported 93% and 67.6%, respectively. ...
... The results of detection from this system on average was 93%. The results can be improved by improving image capturing system [46]. Online monitoring system based on radio local area network for an insulator helpful in determining the leakage current, continuous arching and partial discharges. ...
Outdoor insulator plays a vital role in high voltage transmission and distribution system. The performance and properties of outdoor insulator may severely affect due to various types of pollutants. The failure of insulation in high voltage system results in loss of supply and a huge loss of electrical energy to distribution utilities. In order to reduce power losses and provide a reliable power transmission, selection and design of insulators is very important. To monitor the condition and performance of outdoor insulator in contaminated conditions an appropriate diagnostic technique is required. In this paper various online and offline techniques for conditioning monitoring of outdoor insulators are reviewed under different contaminated conditions. To maintain the healthy environment, the condition monitoring of power line insulators is an important requirement. There are number of techniques that have been introduced to fulfil this requirement. Each technique used at different contaminated condition have their own pros and cons. The findings indicate that the most important effect on the surface of the insulators based on the contamination on the surface leakage current and the flashover voltage. This paper will help in the selection and design of condition monitoring techniques for high voltage outdoor insulator.
... To overcome these problems, there are various types of devices around power lines such as smart sensors [4]- [6], climbing robots [7]- [9], visual cameras [10], [11] and wireless charging stations for drone [12], [13], as shown in Fig. 1. These devices enable engineers to maintain high reliability and to oversee a wide range of power grids through maintenance applications. ...
... The length of the magnetic field path and the number of primary winding turns are defined as leff, and Np, respectively. Consequently, when ipri,rms is smaller than isat,pri, Vpri,max can be derived from Equation (10). Fig. 6 provides an example with different primary side current conditions and isat,pri = 26.5 A. For each primary current magnitude, under condition of unsaturated operation and constant Lm, there exists only one optimal load voltage. ...
... In this case, since ipri,rms is larger than isat,pri, Vpri,max cannot be derived from Equation (10). In the conventional method, the maximum harvested power can be obtained at Vsat, as mentioned above in Section II. ...
Recently, maintenance applications around power lines have been actively studied. These applications usually supply power through magnetic energy harvesting(MEH) to devices around the power line. A major challenge for practical MEH is to overcome magnetic saturation, which can cause degradation of power density under a wide current range in the power line. In this paper, we propose a design methodology to harvest maximized output power by considering the saturation effect. To consider magnetic saturation, the output power model and the saturable magnetizing inductance model based on magnetizing current were comprehensively analyzed. Additionally, the critical point of saturation for the maximum harvested power was analyzed by considering different primary side current conditions. With the proposed design methodology, the accuracy and efficiency of the output model were verified with experimental results compared to the conventional model. To consider the real environment, a 150 kW class of AC resistor load bank was implemented to control the primary current from 0 to 100 A with power frequency of 60 Hz. Experimental results show that the proposed method can harvest an average power of 14.32 W on 70 A power line, which is an increase of 39.8 % compared with the conventional design method.
... Insulator fault detection was proposed by Gu et al. [8], but the fault detected is ice or snow coverage on an insulator. It assumes the snow is only gathered along the side or on top of the insulator caps. ...
... This allows for any radius and number of pixels in the neighbourhood. An additional development to the initial LBP is to use a fundamental pattern called "Uniform" since they have a circular structure that are uniform and have very few spatial transition [6]. Figure 10 describes the uniform pattern which functions as a template for micro-structures such as bright spot (0), edges of varying negative and positive curvature (1 − 7) and flat area or dark spots (8). Figure 11 shows a non-uniform pattern. ...
Damaged insulators may affect the mechanical and electrical performance of an electric power grid, which can lead to the flow of leakage currents through the line supports. This increases electrical losses and voltage drop in the power grid. It also poses a risk to human safety. Thus, it is crucial to monitor and inspect the condition of insulators to detect degradation or damage. However, the traditional method of inspection is inadequate in meeting the growth and development of the present electric power grid. Hence an automated system such as the computer vision method is presently being explored as a means to resolve this crisis safely, speedily and accurately. This paper presents a method that distinguishes between defectuous and non-defectuous power-line insulators. Active Contour model is applied for insulator segmentation in order to determine insulator region of interest. Local binary pattern is used for feature extraction from the insulator region of interest which is then fed to the support vector machine classifier for classification. An accuracy of 94.1% was achieved when morphological operation is used in combination with active contour model for segmentation based on the ground-truths. In addition, local binary patterns feature extraction method outperformed gray level co-occurrence matrix when used with support vector machines.
... For example, Ha et al. (2012) used a microphone array for fault detection on transmission lines and an infrared thermal imaging camera and a charge-coupled device (CCD) camera for verification. Thickness of ice and snow coverage on power transmission line conductors and insulators has been studied using cameras mounted on transmission line towers (see, e.g., Gu et al., 2009;Yu and Peng, 2010;Zhong et al., 2013). Automated monitoring of insulators has been discussed in several articles. ...
To secure uninterrupted distribution of electricity, effective monitoring and maintenance of power lines are needed. This literature review article aims to give a wide overview of the possibilities provided by modern remote sensing sensors in power line corridor surveys and to discuss the potential and limitations of different approaches. Monitoring of both power line components and vegetation around them is included. Remotely sensed data sources discussed in the review include synthetic aperture radar (SAR) images, optical satellite and aerial images, thermal images, airborne laser scanner (ALS) data, land-based mobile mapping data, and unmanned aerial vehicle (UAV) data. The review shows that most previous studies have concentrated on the mapping and analysis of network components. In particular, automated extraction of power line conductors has achieved much attention, and promising results have been reported. For example, accuracy levels above 90% have been presented for the extraction of conductors from ALS data or aerial images. However, in many studies datasets have been small and numerical quality analyses have been omitted. Mapping of vegetation near power lines has been a less common research topic than mapping of the components, but several studies have also been carried out in this field, especially using optical aerial and satellite images. Based on the review we conclude that in future research more attention should be given to an integrated use of various data sources to benefit from the various techniques in an optimal way. Knowledge in related fields, such as vegetation monitoring from ALS, SAR and optical image data should be better exploited to develop useful monitoring approaches. Special attention should be given to rapidly developing remote sensing techniques such as UAVs and laser scanning from airborne and land-based platforms. To demonstrate and verify the capabilities of automated monitoring approaches, large tests in various environments and practical monitoring conditions are needed. These should include careful quality analyses and comparisons between different data sources, methods and individual algorithms.
... Recently, field observations of glass and composite insulators under snow conditions have been conducted in Norway [16][17][18]. The objective was to estimate the ice or snow coverage and the swing angle; however, a large amount of snow accretion could not be observed in any event because the temperatures might be low, the humidities might be low, and the wind velocities might be high. ...
This paper presents evaluation of snow accretion properties of long-rod and cap & pin insulators focusing on the phenomena found in the snowstorm in 2005, which related to wet snow accretion packed with sea-salt. Field observations at severe natural environment and laboratory tests under defined conditions were parallelly carried out in order to clarify wet snow accretion process under various conditions. In field observations, it was confirmed that snow easily accreted on insulators at temperature range especially between 0 and +1.0°C. The long-rod insulator's sheds were bridged more easily than that of cap & pin type because of its narrower shed spacing. In laboratory tests, cylindrical snow accretion, which was found in the snowstorm in 2005, was achieved. The mechanisms on explaining snow accretion on long-rod insulators were found to be similar to those confirmed for wires. The laboratory simulations agree well with the field observations. In order to estimate the amount of snow flux on insulators caused by a snow event for given climatic conditions, an index called the snow accretion potential ability (SAP) was proposed. SAP is defined by using the snow flux and associated with the weight term in the index for the snow stress product (SSP). SAP was adopted to evaluate snow accretion characteristics by field observations and laboratory tests, and the snow accretion phenomenon during a snowstorm in 2005 was discussed.
... Measured data are transferred through the communication system from the test site to the database and stored, and are accessible via a web interface immediately after the measurement [1,2]. Real-time image analysis is performed for each newly captured image and the results are displayed and stored in the system [3]. For measuring the snow/ice, three typical insulators are used in the test site: a composite insulator with a specific profile; a string of glass insulators combining standard and aerodynamic profiles; a string of glass insulator of anti-fog profile, seeFig.1 from left to right for examples of zoomed in insulator images. ...
This paper proposes novel techniques for automatically extracting information from overhead lines based on
automatic image / video processing. Three application scenarios are presented: (a) detecting snow and ice
coverage on insulators for overhead lines; (b) detecting swing angles of insulators; (c) quantifying the visibility of insulators at transmission lines with typical backgrounds. Experiments have been conducted on recorded videos/images of insulators (with different prototypes) for overhead lines in a remote test station in Norway. Results show that the proposed automatic image analysis methods are promising for extracting the status (snow/ice coverage, swing angle, visibility) of insulators and might be applied in the future for other components of the overhead line.
... 2010). Therefore, many scholars have paid attention to the icing monitoring, and different kinds of monitoring devices and methods have been developed in recent years, such as capacitor method (Moser et al., 2009), climatology model method (Nygaard, 2009), video inspection method (Irene et al., 2009), vibrating rods, weight of ice (COST-727, 2006), and load cell (Farzaneh and Savadjiev, 2005). Since the ice load can be easily calculated by the measured tension, load cell method is widely used in China and other countries. ...
A novel optical load cell based on Fiber Bragg Grating sensing technique was proposed for icing monitoring on high-voltage overhead transmission lines. Compared to the conventional strain gauge load cell, the developed optical load cell has several unique advantages such as unnecessary power supply on site, excellent ability for avoiding electromagnetic interference, and long lifespan. In the load cell design, coupled dual-beam (‘S’ beam) structure was adopted to achieve an accurate measurement, and the part of FBG bonding was carefully chosen to withstand equal and opposite strain, which solved the problem of cross-sensitivity between strain and temperature of FBG sensing. A mixed WDM/TDM (Wave-Division Multiplexing/Time-Division Multiplexing) optical fiber network is proposed to construct an icing monitoring system containing hundreds of FBGs. Result from the tension experiment indicates that the load cell is sensitive to tension, and the sensitivity and resolution of the load cell is 0.04903 pm/N and 20.4 N. The temperature effect on the tension measurement, evaluated by putting the load cell in a temperature-controlled cabinet, is less than ± 0.175%. Furthermore, in order to investigate the reliability of the load cell in icing environment, an experiment was carried out in a climatic chamber, and the results prove that the load cell can work properly in harsh environment.
