Application of programmable logic controllers to substation control and protection

This paper describes the application of programmable logic controllers (PLCs) to control and protection of bulk power and regional supply substations. PLC requirements are discussed and the concept of "zones of control" is explained as applied to standard PP&L substation arrangements. The use of a peer-to-peer communication network between logic controllers and other substation equipment is also discussed. Details of an installation completed in spring, 1992, are presented, including experience acquired from power system faults.<
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