Comparison of new rectifier with old rectifiers in Korea Telecom

Many kinds of electronic switching systems are used by Korea Telecom (KT), because of imports from various countries such as USA, Sweden, Belgium, etc., as well as domestic products. Rectifier systems are also imported along with electronic switching systems. It is hard for operators to understand and to maintain them well without operating troubles. As the demands of telecommunications services increase, more power systems are required to supply power to telecommunications equipment. Therefore, KT has been developing a new rectifier system to reduce the cost and floor space requirements of the conventional rectifier systems now in use. The new rectifier system is composed of a distribution part, a control unit and rectifier modules in one rack. There are three kinds of modules: 100 A; 50 A; and 25 A. The maximum output currents of new rectifier modules are 1000 A (100 A), 600 A (50 A), 400 A (25 A) in one rack. The 25 A and 50 A rectifiers are used in remote sites and the 100 A unit is operated in local applications. This paper describes the configuration and operation of the new rectifier and reviews evaluation results of the annual cost and floor space requirements of this system compared with the old rectifier.