Please wait, while we are loading the content...
Please wait, while we are loading the content...
| Content Provider | IEEE Xplore Digital Library |
|---|---|
| Author | Chisholm, William A. Barrett, J. Stephen |
| Copyright Year | 1981 |
| Abstract | Many older transmission lines were designed and constructed with a maximum conductor temperature of 49-55° C (120-1 30° F). The low thermal limit was selected at that time to prevent annealing of aluminum. Unfortunately, on warm days with bright sunshine and low wind speeds, the conductors on these lines can reach the thermal limit without any additional contribution from resistive 12R heating. Annealing temperature limits are now known to be around 1 00° C. However, safe and economical operation of 49° C lines at higher temperatures is still limited by overhead clearance requirements. In Ontario, there are over 1000 km of 11 5-kV and 230-kV lines now operated to this thermal limit. An informal survey has shown that these problem lines exist in most major power utilities. A comprehensive test program was initiated to establish the true thermal capacity of 49° C lines. Four spans of an idle 11 5-kV three-phase transmission line with 477-kcmil conductors were heated by circulating a current of 260 A. This was slighty above the summer-limit current established for Canadian Standards Association clearance requirements. The wind speed, direction, ambient temperature and solar radiation were measured by instruments mounted on the conductor. The resulting conductor temperature and ground clearance were also recorded. The meteorological readings were supplemented with observations from the ground and from nearby weather stations. In two summers of observations, the highest conductor temperature observed was 47° C. |
| Starting Page | 109 |
| Ending Page | 110 |
| Page Count | 2 |
| File Size | 703475 |
| File Format | |
| ISSN | 02721724 |
| Volume Number | 9 |
| Issue Number | 4 |
| Language | English |
| Publisher | Institute of Electrical and Electronics Engineers, Inc. (IEEE) |
| Publisher Date | 1989-04-01 |
| Publisher Place | U.S.A. |
| Access Restriction | Subscribed |
| Rights Holder | Institute of Electrical and Electronics Engineers, Inc. (IEEE) |
| Subject Keyword | Transmission lines Conductors Power transmission lines Land surface temperature Thermal conductivity Annealing Wind speed Aluminum Thermal resistance Heating Ruling-Span Approximation ACSR Conductors Ampacity Overhead Clearance Thermal Ratings Meterology Hot-Wire Anemometer Sag-Tension |
| Content Type | Text |
| Resource Type | Article |
| Subject | Electrical and Electronic Engineering |
National Digital Library of India (NDLI) is a virtual repository of learning resources which is not just a repository with search/browse facilities but provides a host of services for the learner community. It is sponsored and mentored by Ministry of Education, Government of India, through its National Mission on Education through Information and Communication Technology (NMEICT). Filtered and federated searching is employed to facilitate focused searching so that learners can find the right resource with least effort and in minimum time. NDLI provides user group-specific services such as Examination Preparatory for School and College students and job aspirants. Services for Researchers and general learners are also provided. NDLI is designed to hold content of any language and provides interface support for 10 most widely used Indian languages. It is built to provide support for all academic levels including researchers and life-long learners, all disciplines, all popular forms of access devices and differently-abled learners. It is designed to enable people to learn and prepare from best practices from all over the world and to facilitate researchers to perform inter-linked exploration from multiple sources. It is developed, operated and maintained from Indian Institute of Technology Kharagpur.
Learn more about this project from here.
NDLI is a conglomeration of freely available or institutionally contributed or donated or publisher managed contents. Almost all these contents are hosted and accessed from respective sources. The responsibility for authenticity, relevance, completeness, accuracy, reliability and suitability of these contents rests with the respective organization and NDLI has no responsibility or liability for these. Every effort is made to keep the NDLI portal up and running smoothly unless there are some unavoidable technical issues.
Ministry of Education, through its National Mission on Education through Information and Communication Technology (NMEICT), has sponsored and funded the National Digital Library of India (NDLI) project.
| Sl. | Authority | Responsibilities | Communication Details |
|---|---|---|---|
| 1 | Ministry of Education (GoI), Department of Higher Education |
Sanctioning Authority | https://www.education.gov.in/ict-initiatives |
| 2 | Indian Institute of Technology Kharagpur | Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project | https://www.iitkgp.ac.in |
| 3 | National Digital Library of India Office, Indian Institute of Technology Kharagpur | The administrative and infrastructural headquarters of the project | Dr. B. Sutradhar bsutra@ndl.gov.in |
| 4 | Project PI / Joint PI | Principal Investigator and Joint Principal Investigators of the project |
Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon |
| 5 | Website/Portal (Helpdesk) | Queries regarding NDLI and its services | support@ndl.gov.in |
| 6 | Contents and Copyright Issues | Queries related to content curation and copyright issues | content@ndl.gov.in |
| 7 | National Digital Library of India Club (NDLI Club) | Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach | clubsupport@ndl.gov.in |
| 8 | Digital Preservation Centre (DPC) | Assistance with digitizing and archiving copyright-free printed books | dpc@ndl.gov.in |
| 9 | IDR Setup or Support | Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops | idr@ndl.gov.in |
|
Loading...
|