Integration of protection and control for railway power systems

The paper describes the evolution of conventional control, monitoring and protection equipment for railway power system applications into "The intelligent substation", fully utilising information technology. Traditionally there were separate islands with various stand-alone equipment such as protection relays, event recorders, disturbance recorders, measuring devices, alarm systems, remote terminal units and control panels built up with conventional electromechanical relays and switches. The paper discusses the advantages, and the concerns, of an integrated approach for substation automation, based on modern microprocessor, software and communication technology.