Submersible Silicon Rectifier Unit for Consolidated Edison Company of New York

A large section of Manhattan still requires dc power as well as the ac grid network. This dc power has been supplied from rotary-converter substations. The city is now in the process of changing from the rotary converters to rectifier units located in under-the-street vaults. These silicon rectifier units are submersible, oil-cooled, and are connected directly to the 208Y/120-four-wire ac network. The 250-kW 125/250-volt dc output is then connected to the dc distribution system. The application, design of the unit, and analysis of the dc network is discussed in this paper.