Switchgear and Control for an Electronic Power Converter

The electronic power converter, controlled by the equipment described in this paper, consists of two units rated 10,000 kw installed and operating at the Edgar Thomson Works of the Carnegie-Illinois Steel Corporation. The power converters connect a 60-cycle 69-kv system and a 25-cycle 44-kv system with a permissible power transfer of 20,000 kw in either direction between the systems. Transfer of power by rectification and inversion and the design of the electronic power converter are discussed in companion papers.^1,2 The switchgear and control devices are discussed in this paper and for convenience and clarity, the discussion is divided into three main headings: ``Switching,´´ ``Control,´´ and ``Protection.´´