Laplace Transform for Finite Element Analysis of Electromagnetic Interferences in Underground Metallic Structures

A numerical methodology is proposed for the calculation of transient electromagnetic interference induced by overhead high-voltage power lines in metallic structures buried in soil—pipelines for oil or gas transportation. A series of 2D finite element simulations was employed to sample the harmonic response of a given geometry section. The numerical inverse Laplace transform of the results allowed obtaining the time domain evolution of the induced voltages and currents in the buried conductors, for any given condition of the power line.

Change in the agrochemical properties of soils and the productivity of the wheel under the influence of electromagnetic waves

In recent years, in the world, the anthropogenic impact on the soil, entailing various changes in its properties, is becoming more severe. Especially it is necessary to note the lands located on the boundaries of the protection zones of linear objects. This article studies the agrochemistry of soils that are under zones and linear protection objects and the effect of electric waves on wheat productivity. Overhead power lines have a negative impact on the environment, in particular on its ecological, social, and economic systems due to the high intensity of the electromagnetic field around the lead wires. High-voltage power lines do not significantly affect the content of humus and nutrients.

Analysis of Induced Voltage on Pipeline Located Close to Parallel Distribution System

Gas and oil pipelines are widely used to supply customers. They are often laid in parallel with high voltage power lines, sharing right of way. When the pipeline is located near overhead high-voltage power, corrosion caused by induced voltages from AC power lines can occur in utility pipelines. Therefore, the calculation of induced voltage is always required for both interference and maintenance workers as well as pipeline facility safety. For parallel distribution lines, the calculation method for the induced voltage is not suitable due to the excessive error caused by using the screening factors of the neutral current. For a more practical analysis of the induced voltage, a new analysis is needed using the actual neutral current and which also considers the overhead ground conductor and the neutral conductor. This paper analyzed the induced voltage from a parallel distribution system using Carson’s formula and vector analysis. Simulation analysis results are verified by separate Electromagnetic Transient Program (EMTP) simulation.

Surface-Integrated Electric Field Sensor for the Detection of High-Voltage Power Lines

When a drone is used for inspection of facilities, there are often cases in which high-voltage power lines interfere, resulting in the drone being caught or falling. To prevent this type of incident, drones must be capable of detecting high-voltage power lines. Typically, a strong electric field is formed around the high-voltage lines. To detect the electric fields around high-voltage lines, this study proposes an electric field sensor that may be integrated within the body of a drone. In a laboratory environment, a voltage of 25 kV was applied to an overhead line, and the induced voltage in the proposed sensor was measured at various electric field intensities. Over an electric field range of 0.5 to 10.1 kV/m, a voltage of 0 to 0.77 V was measured with each proposed sensor. In addition, the electric field and the voltage induced in the sensor were measured in a real-world railway environment with overhead lines. Under these conditions, the proposed sensor has the compensated value of 4.5 when the measured electric field was 4.05 kV/m. Therefore, the proposed sensor may be applied in drones to measure large electric fields and to detect the presence of high-voltage lines in its vicinity.

Place and Role of Some Mass Bird Species in Biological Damage in the Fergana Valley of Uzbekistan

The article provides data on the place and role of some common bird species in the Fergana Valley in biological damage. The reasons for the occurrence of biological damage in birds are discussed, the nature and degree of biological damage caused by white storks, green bee-eaters, myna, Indian and field sparrows on fish farms, power grid enterprises, viticulture and grain crops (wheat and rice) are discussed. Building their huge nests on the poles of high-voltage power lines during the year, white storks make short circuits, which lead to an interruption in the power supply. In the post-nesting period, large flocks of white storks arrive at fish farms. One bird eats an average of 600–800 g of fish per day. During spring and autumn migrations, green bee-eaters gathering at beekeeping farms, one pair per day destroys about 350–400 worker bees. Mynas, after the chicks leave the nests, together with fledglings, flies into the vineyards and, on average, damage 18.5% of the grape harvest. Field and Indian sparrows consume an average of 16.95% of the crop during the milky-wax ripeness of wheat. In rice fields during autumn migrations, the harm from sparrows is 2.1–13.4%. The article also provides data on some of the repellents used in preventing and reducing bio-damage caused by birds, discusses their effectiveness.

Classification of high-voltage power line structures in low density ALS data acquired over broad non-urban areas

Airborne laser scanning (ALS) has gained importance over recent decades for multiple uses related to the cartography of landscapes. Processing ALS data over large areas for forest resource estimation and ecological assessments requires efficient algorithms to filter out some points from the raw data and remove human-made structures that would otherwise be mistaken for natural objects. In this paper, we describe an algorithm developed for the segmentation and cleaning of electrical network facilities in low density (2.5 to 13 points/m2) ALS point clouds. The algorithm was designed to identify transmission towers, conductor wires and earth wires from high-voltage power lines in natural landscapes. The method is based on two priors i.e. (1) the availability of a map of the high-voltage power lines across the area of interest and (2) knowledge of the type of transmission towers that hold the conductors along a given power line. It was tested on a network totalling 200 km of wires supported by 415 transmission towers with diverse topographies and topologies with an accuracy of 98.6%. This work will help further the automated detection capacity of power line structures, which had previously been limited to high density point clouds in small, urbanised areas. The method is open-source and available online.

Installation of Clip-Type Bird Flight Diverters on High-Voltage Power Lines with Aerial Manipulation Robot: Prototype and Testbed Experimentation

This work presents the application of an aerial manipulation robot for the semi-autonomous installation of clip-type bird flight diverters on overhead power line cables. A custom-made prototype is designed, developed, and experimentally validated. The proposed solution aims to reduce the cost and risk of current procedures carried out by human operators deployed on suspended carts, lifts, or manned helicopters. The system consists of an unmanned aerial vehicle (UAV) equipped with a custom-made tool. This tool allows the high force required for the diverter installation to be generated; however, it is isolated from the aerial robot through a passive joint. Thus, the aerial robot stability is not compromised during the installation. This paper thoroughly describes the designed prototype and the control system for semi-autonomous operation. Flight experiments conducted in an illustrative scenario validate the performance of the system; the tests were carried out in an indoor testbed using a power line cable mock-up.