Features and Requirements Concerning Reliability of DC Power Supply for Telecommunications

The known publications concerning reliability in DC Power Plants have been either superficial or restricted to a few specific sets of devices (e.g. rectifiers, converters), what implies in misleading and other inadequacies. The paper aims at divulging the results of studies and researches as to reliability, held in Brazil, which were the basis for the definitions regarding the standardization of Primary DC Power Plants for all the Brazilian Telecommunication Companies forming the TELEBRAS Group. A consistent analysis is made to deter mine the overall power feeding reliability taking into account all the important factors involved. Suitable approaches are made regarding assessment of some parameters such as: time for failure detection (td); probability of failure in the starting of an emergency AC generator (or any other device which either does not operate continuously or has no self-supervision); factor of success in repairing proceeding as a function of battery autonomy period.