Control and supervision of Sellafield electrical distribution system using a computer-based telecontrol system

Sellafield nuclear fuel reprocessing and associated waste management plant utilises 11 kV (HV) and 415 V (MV) systems in 55 substations to distribute a power demand of approximately 50 MW. Until 1985, the HV and MV distribution systems were controlled from a central control room using conventional discrepancy switches on a hard-wired mimic. During 1985, the hard-wired system was replaced with a computer-based telecontrol system to cope with the envisaged distribution system expansion due to the construction of major new plants. The telecontrol system controls approximately 245 HV and 360 MV circuit breakers. The author discusses the system requirements and the telecontrol system configuration. The operation of the system is described in detail