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Jicable'03
6th International Conference on Insulated Power Cables
PARIS-VERSAILLES, FRANCE
22-26 JUNE, 2003 |
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Tutorials
Three high-level tutorials will be given by professors during the Sunday afternoon of 22 June, 2003 for a limited number of people. Registration to these tutorials may be made by use of the attached registration form.
The various tests used to evaluate the quality of the materials and cable systems as well as the reliability of cables and accessories installed or in service are reviewed and discussed. The tutorial starts with a brief description of the various components in up-to-date extruded cables and accessories; some emphasis is put on the parts most likely to fail in service. Tests known as engineering tests performed during the development of new materials or cables are then discussed. The principal aging mechanisms leading to most failures are also reviewed with the methods often used to limit their detrimental influence. Factory tests routinely performed by cables and accessories makers to validate the quality of their commercial products are discussed. The various installation and maintenance tests (PD, oscillating waves, low-frequency, etc.) performed in the field are presented and the significance of their results is discussed. Finally, a brief discussion of the new tests to be developed for a long-term and cost-efficient maintenance plan is made.
Recent breakdowns, probably of thermal origin, have shown that the environment of underground cables is not always controlled. These problems sometimes have dramatic consequences (supplying of the city of Auckland in 1998). This tutorial gives a description of the knowledge obtained over almost 40 years on the environment of the lines, then on recent developments of controlled fill or grout. A critical analysis of the thermal assumptions of the soil is proposed. Numerical simulations on recent damage and ground studies make it possible to suppose that the thermal resistivity reference values of ground can be exceeded in a few situations, especially in urban areas (backfill not controlled and frequent presence of watertight coverings). This situation can result in an over-estimation of the underground lines’ ampacity, with major consequences on the lines’ most sensitive to temperature (oil-filled cables, directly buried cables). The tutorial is intended to focus the participants’ attention on some essential points, in order to guide them towards a better estimate of the maximum permissible ratings of existing lines, and to guarantee their durability.
Ageing and failures of cable systems are dominant factors related to the (expected) reliability of a network. Asset management is partly based on the knowledge of ageing processes and failure mechanisms and it is known that in the present market situation, asset management of cables has become an important subject. On the one hand it can help to prevent outages and on the other hand it may give insight in the limits of a cable and with that in the opportunities to increase cable loads where possible. This tutorial will discuss :
Important issues here are :
Contact : contact@jicable.org Modified Last : 12/03/2022 |