Vegetation under power lines control and maintenance reports. Overhead lines represent a substantial component of the infrastructure in any electricity related utility and therefore play a major role in the sustainability of an electricity utility business. Advanced technology deployment is required to manage the overhead lines effectively. Owing to rising global electricity consumption, population growth, access to better standards of living, rising to industrial production, power grid must be. Pictorial field guides for assessment and inspection of overhead transmission lines. The lightning study of overhead transmission lines marjola puka1, nako hobdari2 1lecturer, electrotechnicdepartment,tirana, albania 2profesor, eletric power systemdepartment,electrical engineering faculty, polytechnic university of tirana, abstract. Standard for distribution line design overhead these standards created and made available are for the construction of ergon energy infrastructure. Visualbased positioning of aerial maintenance platforms on. Pdf unmanned aerial vehicles uavs are an emerging and promising alternative for monitoring of transmission lines in terms of flexibility. It applies to work practices on all overhead lines and associated apparatus including overhead lines within a. Installation and maintenance manual bastian solutions. Such maintenance work, which can add 50 years of life to a transmission line, requires highly qualified electricity technicians and mechanics with the tremendous physical and mental strength needed to gain access to the nearly impenetrable places where these. Maintenance of transmission and distribution lines transmissionline inspection on globalspec. These instructions are to be deleted so that the cover page is the first page of the main specification.
External companies should not use these standards to construct nonergon energy assets. In the past, the maintenance on the transmission lines and substations required. Overhead line preventive maintenance strategy based on. Maintenance of a highvoltage overhead transmission line mdpi. Calculation of the two high voltage transmission line. An overhead power line is a structure used in electric power transmission and distribution to transmit electrical energy across large distances. Comparison of overhead and underground transmission lines 1. There are two types of transmission line conductors.
Comparison of overhead and underground transmission lines name. The focus of this paper is the analysis of lightning in overhead transmission lines. Maintenance technique llmt for overhead lines based on condition monitoring to maintain system reliability. In distribution and transmission electric power companies, many losses and risks are associated with corrosive processes that occur in buried structures, such as tower leg foundations of overhead transmission lines. To ensure high reliability and availability of the overhead lines for bulk electricity transmission.
Repair and maintenance of power distribution lines ncert. Canada, overhead lines for voltage of 765 kv were built. Maintaining transmission line ratings consistent with as. Since most of the insulation is provided by air, overhead power lines are generally the lowestcost method of transmission for large quantities of electric energy. Epris overhead transmission inspection and assessment guidelines 1012310 provides a stateoftheart resource on the latest inspection and assessment methods to help utilities increase reliability and reduce maintenance costs. Through the inspection and maintenance of overhead. Overhead transmission o an overhead power line is a structure used in electric power transmission and distribution to transmit electrical energy along large distances. Overhead transmission lines shorter than 80 km 50 miles can be modeled as a series resistance and inductance, since the shunt capacitance can be neglected over short distances.
These standards ensure meeting of ergon energys requirements. Mechanical design of overhead transmission lines conductor material the conductor is one of the important items as most of the capital outlay is invested for it. Overhead line ratings transmission vs distribution distribution design aspects. Designed for electrical technicians and engineers, this course covers concepts that. Operation, maintenance, refurbishment 10 and uprating. Overhead transmission line the purpose of this article is to give a general overview of the steps that are necessary in the planning and construction of a typical overhead transmission line, to give newcomers to the trade a general format to follow, and assist transmission design engineers in understanding how such lines are built. Transmission maintenance is undertaken in accordance with the transmission asset maintenance policy to ensure that the transmission system can operate in a safe, secure and reliable manner. Personal protective grounding of overhead transmission lines standard number. Guidelines for the construction and maintenance of. Transmission line design manual bureau of reclamation. Over head transmission lines live line maintenance. The chapters on line survey, construction and maintenance address.
Overhead conductors, made of naked metal and suspended on insulators, are preferred over underground conductors because of the lower cost and easy maintenance. Possible visions for the inspection of transmission lines in a multidecade time frame are. These days, the material is steel, but in the past, wooden tower feet were also used in 110kilovolt kv lines and in some 220 kv lines. Electrical design of overhead power transmission lines. The standard is applicable to all high voltage over v overhead transmission lines owned by artc. In figure 1, the existing temperature calculation models of overhead transmission lines mostly consider the entire conductor as an isothermal body or only considers the radial heat transfer path. Because overhead transmission lines are constructed over open areas where it is not possible to. Since most of the insulation is provided by air, overhead power lines are generally the lowestcost method of power transmission for large quantities of. Tao in respect to the maintenance of the transmission system are further detailed under section 8 of the infrastructure agreement3. The text highlighted in yellow is to be replaced with relevant content and the highlighting removed. Introduction when the high voltage transmission lines are designed, it is inevitably needed to intersect across, change the arrangement modes of wires, and etc. Maintenance of transmission linesthe transmission lines play a very important role in transmitting the huge quantum of electrical power generated at various generating stations to the whole area of the country from one end to other end over a distance of several hundreds of kilometers.
This course is aimed at providing insight into the effective management of the electricity overhead lines from an inspection and maintenance perspective. Safety in overhead line maintenance training course. Specific component requirements are listed in their own sections. One of our largest segment of clients is major utility companies, state and local government, and communication providers. Pdf power line robotic device for overhead line inspection and. Manual for transmission lines and substation construction. Cowritten by experts in power engineering, this detailed guide addresses component selection and design, current ieee standards, loadflow analysis, power. The inductive reactance at 60 hz for overhead lines is typically much larger than the resistance of the line. Main specification for the construction of overhead.
These individuals require an understanding of the theory and practice of overhead lines in planning, design, construction, operation, and maintenance. They need to understand how the physical components of transmission lines fit into an integrated design. Overhead lines ohl operating at 400kv, form the backbone of clp powers transmission network. Field guides are designed to aid utility field crews in assessing observed conditions on structures, identifying specific problems, and deciding on a course of action. Transmission line towers constitute about 28 to 42 percent of. Overhead highvoltage lines are a common choice for power transmission, but their planning, installation and management are often challenging tasks because. Dispersionless transmission lines because lo and co do not depend on frequency for a superconductor, the phase velocity is independent of frequency. The overhead utility line part of our business includes the installation and maintenance of overhead electrical power lines.
Comparison of overhead and underground transmission lines. Overhead power lines presents not only the scientific and engineering basis for the electric and mechanical design, but also comprehensively describes all aspects of most recent technology, including the selection and design of components such as conductors, insulators, fittings, supports and foundations. Safe work practices on high voltage overhead lines transgrid. The fundamentals and practice of overhead line maintenance focuses on providing the power utility maintenance practitioner with comprehensive insight into the philosophy and theory of overhead line maintenance 2 kv and above, its management and effective application. Maintenance of a transmission line is a fundamental part of its functioning, a need that is accentuated by its outdoors location. Due to the limited experience, reliable figures for maintenance costs for ugc. Unlike underground cables, overhead lines are vulnerable to external environmental attacks, such as adverse weather, high humidity, pollution, ground stability, vegetation, and flying. Pdf visualbased positioning of aerial maintenance platforms on. The assets are ageing and this aspect must be taken into account in defining the asset management strategy. Overhead highvoltage lines are a common choice for power transmission, but their planning, installation and management are often challenging tasks because of the surrounding public interest and of their importance as critical infrastructures. Overhead transmission inspection and assessment guidelines. This document has an updated reference number and supersedes railcorp publication ep 10 00 00 01 sp transmission line standard for design and construction version 2. Maintenance practices for transmission overhead lines abstract. Handling overhead line conductors at ground level insulated work methods.
Home courses electrical and power engineering overhead transmission lines problems and maintenance. Overhead transmission line asset management provides participants with a fundamental understanding of the commissioning, maintenance and operations techniques that are a vital part of any overhead transmission line ohtl asset management program. Vegetation clearing for construction, maintenance and repair activities access, as well as protection of the cables from root systems, precludes most. Pdf maintenance of a highvoltage overhead transmission. Undergrounding high voltage electricity transmission lines. Future inspection of overhead transmission lines electric power. It is essential that overhead networks must provide open access to ipps and prosumers. The contract outlines the construction of 245km of 2kv single circuit overhead transmission line connecting the proposed substation at kabarnet, nyahururu, narok, bomet.
This instruction defines the requirements for the routine inspection and maintenance of overhead lines operating at voltages of 33kv and above, and the overhead pilot cables associated with. A1 3 term and acronym definition list termacronym definition ac alternating current ac merge format of ac conveyor used to converge multiple lines of product flow to a single discharge bf between frame. By combining the parameters in the equation to the specific reactive power. Introduction western area power administration western is planning to construct, own, operate, and maintain a power transmission facility between trinity dam and a new switchyard at weaverville, trinity county, california. Unlike underground cables, overhead lines are vulnerable to external environmental attacks, such as adverse weather, high humidity, pollution, ground stability, vegetation, and flying objects etc. Keeping electricity reliable requires unobstructed access for maintaining power lines, facilities and rights of way. Overhead transmission lines, distance of two lines, equation of wire balance, wire sag 1. Proper maintenance of line improves its life drastically. Maintenance of a highvoltage overhead transmission line. Transmission line maintenance fingrids transmission lines are usually constructed using guyed towers. Transmission line rightofway use guidelines progress energys goal is to provide safe, reliable and economical electrical service to all customers. Overhead transmission lines problems and maintenance. It consists of one or more conductors commonly multiples of three suspended by towers or poles.
Pds 20 ep 10 01 00 06 sp transmission line standard. Also, the amount of attenuation is extremely small, since this is. Electrical design of overhead power transmission lines discusses everything electrical engineering students and practicing engineers need to know to effectively design overhead power lines. The purpose of this article is to give a general overview of the steps that are necessary in the planning and construction of a typical overhead transmission line, to give newcomers to the trade a general format to follow, and assist transmission design engineers in. Therefore, proper choice of material and size of the conductor is of considerable importance. Scope this work practice covers the use of personal protective grounds on the seattle city light scl 115 and 230 kv overhead transmission systems. Overhead line preventive maintenance strategy based on condition monitoring and system reliability assessment article in ieee transactions on power systems 294. The most common methods for transfer of electric power are. An overhead power line is an electric power transmission line suspended by towers or utility poles. Pdf methodology for planning tower leg foundations. This course examines hazards that may be present during overhead line maintenance operations.