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DC UPS system's reliability performance: Facts and fiction

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Details

Original languageEnglish
Title of host publicationTELESCON 1997 - 2nd International Telecommunications Energy Special Conference
PublisherInstitute of Electrical and Electronics Engineers Inc.
Pages237-243
Number of pages7
ISBN (Electronic)9638111623, 9789638111623
DOIs
Publication statusPublished - 1 Jan 1997
Externally publishedYes
Publication typeNot Eligible
Event2nd International Telecommunications Energy Special Conference, TELESCON 1997 - Budapest, Hungary
Duration: 22 Apr 199724 Apr 1997

Publication series

NameTELESCON 1997 - 2nd International Telecommunications Energy Special Conference

Conference

Conference2nd International Telecommunications Energy Special Conference, TELESCON 1997
CountryHungary
CityBudapest
Period22/04/9724/04/97

Abstract

Reliability performance of a DC UPS system having redundant (n+1) rectifiers and battery back-up can be naturally very high. Emergence of microcomputer based intelligent supervision and control system as well as low voltage disconnection (LVD) facilities can, however, drastically reduce or even totally destroy the naturally high reliability performance. This is quite worrying because high reliability performance is the basis for the quality of Telecom services. The reliability performance of a redundant rectifier system depends on the reliability of the individual rectifiers, on the ability of the supervision system to detect a failed unit and on the existence of common mode failure sources. The typical common mode failure sources are overvoltage protection, remote voltage control, remote shut down, internal short circuits at the output, unwise location and insufficient monitoring of LYD facilities. This paper describes the methodology to analyze the availability and reliability performance based on Markov chains. Methods and ways by which the reliability problem can be rectified are also addressed.