Data communications for power system relaying

Electric power utilities are probably the largest users of real-time data in the world. The minute by minute operation of the power network involves communication systems for system supervision SCADA, telecontrol and teleprotection. With the introduction of microprocessor technology and the need to manage the asset more effectively, the growth in communications has been explosive. This paper discusses the communication systems and signaling methods with particular interest in the operation of the relaying function and in their interaction with the other power network protection and control systems. The availability of a common communications standard, which is particularly important for transfer tripping and trip acceleration application, and for status and alarm data transfer within the network´s supervisory and control systems is also discussed