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Improved estimates from the differential equation algorithm by median post-filtering

Akke, Magnus LU and Thorps, J S (1997) IEEE 6th International Conference on Developments in Power System Protection p.235-238
Abstract
Fast line relaying algorithms are motivated by the need to keep the fault clearing time as short as possible. Fast fault clearing reduces the risk for transient instability, thermal stress on equipment and risk for personnel injuries. There exists, at least, three different themes in transmission line protection: impedance algorithms differential equation algorithms (DEA); and travelling wave algorithms. This paper focuses on the differential equation algorithm. The paper presents the equations used in the differential equation algorithm. Both the continuous-time and the discrete-time equations are given. The very poor estimates are explained by the equations determinant. At some isolated points the determinant approaches zero and the... (More)
Fast line relaying algorithms are motivated by the need to keep the fault clearing time as short as possible. Fast fault clearing reduces the risk for transient instability, thermal stress on equipment and risk for personnel injuries. There exists, at least, three different themes in transmission line protection: impedance algorithms differential equation algorithms (DEA); and travelling wave algorithms. This paper focuses on the differential equation algorithm. The paper presents the equations used in the differential equation algorithm. Both the continuous-time and the discrete-time equations are given. The very poor estimates are explained by the equations determinant. At some isolated points the determinant approaches zero and the equations become singular. This results in useless, often extreme, estimates. A simulation shows that a linear post-filter is unsuitable for this problem. To solve the problem we suggest a median post-filter. This filter type totally rejects the extreme values, and therefore produce fast and accurate estimates. (Less)
Please use this url to cite or link to this publication:
author
and
organization
publishing date
type
Chapter in Book/Report/Conference proceeding
publication status
published
subject
keywords
continuous-time equations determinant differential equation algorithm discrete-time equations estimates improvement fast line relaying algorithms median post-filtering personnel injuries risk reduction short fault clearing time thermal stress reduction transient instability risk reduction
host publication
Sixth International Conference on Developments in Power System Protection (Conf. Publ. No. 434)
issue
434
pages
235 - 238
publisher
IEEE - Institute of Electrical and Electronics Engineers Inc.
conference name
IEEE 6th International Conference on Developments in Power System Protection
conference location
London, United Kingdom
conference dates
0001-01-02
external identifiers
  • scopus:0030654115
ISSN
0537-9989
ISBN
0-85296-672-5
DOI
10.1049/cp:19970071
language
English
LU publication?
yes
id
6d72daa5-9141-4175-a619-b64936715ab2 (old id 4589045)
alternative location
http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=608190
date added to LUP
2016-04-01 16:39:32
date last changed
2022-04-15 06:06:04
@inproceedings{6d72daa5-9141-4175-a619-b64936715ab2,
  abstract     = {{Fast line relaying algorithms are motivated by the need to keep the fault clearing time as short as possible. Fast fault clearing reduces the risk for transient instability, thermal stress on equipment and risk for personnel injuries. There exists, at least, three different themes in transmission line protection: impedance algorithms differential equation algorithms (DEA); and travelling wave algorithms. This paper focuses on the differential equation algorithm. The paper presents the equations used in the differential equation algorithm. Both the continuous-time and the discrete-time equations are given. The very poor estimates are explained by the equations determinant. At some isolated points the determinant approaches zero and the equations become singular. This results in useless, often extreme, estimates. A simulation shows that a linear post-filter is unsuitable for this problem. To solve the problem we suggest a median post-filter. This filter type totally rejects the extreme values, and therefore produce fast and accurate estimates.}},
  author       = {{Akke, Magnus and Thorps, J S}},
  booktitle    = {{Sixth International Conference on Developments in Power System Protection (Conf. Publ. No. 434)}},
  isbn         = {{0-85296-672-5}},
  issn         = {{0537-9989}},
  keywords     = {{continuous-time equations determinant differential equation algorithm discrete-time equations estimates improvement fast line relaying algorithms median post-filtering personnel injuries risk reduction short fault clearing time thermal stress reduction transient instability risk reduction}},
  language     = {{eng}},
  number       = {{434}},
  pages        = {{235--238}},
  publisher    = {{IEEE - Institute of Electrical and Electronics Engineers Inc.}},
  title        = {{Improved estimates from the differential equation algorithm by median post-filtering}},
  url          = {{http://dx.doi.org/10.1049/cp:19970071}},
  doi          = {{10.1049/cp:19970071}},
  year         = {{1997}},
}