Voltage Electrical Lines Research Articles

Neural Network-Based Fault Diagnosis of Joints in High Voltage Electrical Lines

Neural Network-Based Fault Diagnosis of Joints in High Voltage Electrical Lines

Optimization techniques for determining the section and the economic current density of medium and low voltage power lines

In most situations encountered in practice, the choice of section of the overhead or cable lines is made on the basis of the economic criterion in normal operating mode, which is the basic criterion for sizing. The central theme of this paper is the optimization of the section and the economic current density in the medium and low voltage power lines. The first part presents the calculation mathematical model for the determination of the optimal section and the economic current density for the medium and low voltage electric lines, and the section obtained has to be verified based on the criteria of the maximum admitted voltage drop and the mechanical resistance. The case studies presented reflect the results of the corresponding voltage drop in the case of an electric line portion through which a load unit is transmitted, respectively the power corresponding to the optimal cross section and the maximum voltage drop allowed for a medium voltage overhead line.

Dual arm electrical transmission line robot: motion through straight and jumper cable

ABSTRACTGround-based high voltage electrical line inspection is one of the difficult and highly dangerous job as far as a manual worker is concerned. The transmission line inspection by robots avoids temporary interruption of power supply that affects the end user and transmission grid. Also, robot-based inspection reduces maintenance cost and hazards. The electrical line inspection is normally carried out using binoculars and rarely by helicopters in most of the countries because of the low cost. Wire traversing or aerial robots are being used in Japan, Canada, USA and Russia for inspecting and monitoring faults in transmission lines and towers. However, most of these robots require a lot of human effort for installation due to its weight and complex design. Cost of these robots is also very high. This paper presents the mechanical design, fabrication and testing of a novel, low cost, light weight and compact power transmission line inspection robot. This work also includes kinematic, static and dynamic analysis of various subsystems of robot. Proposed robot is capable of traversing on straight transmission line and jumper cables present in tension towers. The robot has 10 DoF dual arm for crossing operation and a base system to achieve the locomotion.

Reduction of the Low Voltage Substation Constraints by Inserting Photovoltaic Systems in Underserved Areas

Background: The improvement of the voltage in power lines and the respect of the low voltage distribution transformer substations constraints (Transformer utilization rate and Voltage drop) are possible by several means: reinforcement of conductor sections, installation of new MV / LV substations (Medium Voltage (MV), Low Voltage (LV)), etc. Methods: Connection of mini-photovoltaic systems (PV) to the network, or to consumers in underserved areas, is a well-adopted solution to solve the problem of voltage drop and lighten the substation transformer, and at the same time provide clean electrical energy. PV systems can therefore contribute to this solution since they produce energy at the deficit site. Results: This paper presents the improvement of transformer substation constraints, supplying an end of low voltage electrical line, by inserting photovoltaic systems at underserved subscribers. Conclusion: This study is applied to a typical load pattern, specified to the consumers region.

Electrical Burns in Chinese Fishermen Using Graphite Rods Under High-Voltage Cables

The 42 patients admitted to our Burn Center from January 1, 1994 to December 31, 2005, with electrical and fire burn injuries caused by electricity-conducting graphite-carbon fishing rods touching overhead high voltage electrical lines were epidemiologically studied retrospectively. All patients were men, with a mean age of 40.33 years. The majority of patients (59.5%) were burned with less than 10%, mostly deep burns. The hand was the predominant electricity "entry" point and foot was the most frequent "exit" point. Admissions increased from 5 in 6 years, 1994 to 2000, to 15 in 3 years, 2000 through 2002, to 22 cases in 3 years, 2003 through 2005. Spring and fall, and months May and October were times of highest incidence. The treatment was complex, difficult, long, and costly. Thirty-eight patients (90.4%) required operations, including early excision and graft (34 patients), and amputation (14 patients). Two patients had an inhalation injury that necessitated a tracheostomy and four victims had additional skin and soft-tissue injury. Thirty-two patients had a record of unconsciousness immediately after the electrical injury and atrial premature beats were a frequently found arrhythmia. A significant (P <.01) increase in serum creatine kinase MB fraction was found in 11 patients. The mean time in hospital of the survivors was 28.97 days. Acute renal failure was the commonest complication and one patient died of sepsis with giving a mortality rate of 2.4%. Caution and preventive measures are warranted while fishing near electrical wires, and improvements in electrical burn treatment are needed.

Mathematical Model of Ice Melting on Transmission Lines

During ice storms, ice forms on high voltage electrical lines. This ice formation often results in downed lines and has been responsible for considerable damage to life and property as was evidenced in the catastrophic ice storm of Quebec recently. There are two main aspects, viz., the formation of ice and its timely mitigation. In this paper, we mathematically model the melting of ice due to a higher current applied to the transmission wire. The two dimensional cross-section contains four layers consisting of the transmission wire, water due to melting of ice, ice, and the atmosphere. The model includes heat equations for the various regions with suitable boundary conditions. Heat propagation and ice melting are expressed as a Stefan-like problem for the moving boundary between the layers of ice and water. The model takes into account gravity which leads to downward motion of ice and to forced convection of heat in the water layer. In this paper, the results are applied to the case when the cross-sections are concentric circles to yield melting times for ice dependent on the increase in intensity of the electrical flow in the line.

Eco-sustainable energy and environmental strategies in design for recycling: the software “ENDLESS”

This paper describes a model, named “ENDLESS”, useful to address the design process towards more eco-compatible solutions. In particular, this tool can support the designer in the choice of the product with an higher recyclability potential from a set of different alternatives. The model takes into consideration a Multi-Attribute Decision-Making method and allows calculating a “Global Recycling Index” (GRI) starting from a set of energy, environmental, technical and economic indicators. A weight is assigned to each parameter following the experience of the designer; a sensitivity analysis is then performed to state how the different assumptions can affect the final results. The model is implemented in a software and applied to a case study: to establish the best recyclability option of middle and low voltage electrical lines used for electricity distribution in Italy.

Evaluation of Proximity Warning Devices for Cranes

Extensive testing and evaluation of the proximity warning device (PWD) have clearly shown that the concept of using the measurement of the electric field to determine the relative position of a crane with respect to power lines to be flawed. PWDs tested are not dependable as their warning is, in many cases, nonrepeatable and, in some instances, totally unreliable. The devices depend entirely on a measurement of |E| to detect and warn of proximity to high voltage electric power lines. However, the typical |E| configuration produced by the presence of high voltage electric lines is subject to many variables, including but not limited to