Development of Protective Relaying Equipment with Application of Semiconductor and Microprocessor in Substations

摘要

This paper mainly reviews the development of protective relaying equipment in modern substations. As electronics and computer technologies progress, more original electromechanical relays (EMRs) in the substations are being replaced by advanced semiconductor-based relays, say, solid-state relays (SSRs), and microprocessor-based automatic protective equipment, so that there is a remarkable increase in the degree of substation automation than before. In addition, industrial programmable logic controllers (PLCs) are being used as a type of relaying equipment in the substation automation gradually due to their high flexibility and reliability. In fact, all of them constitute main protective relaying equipment. In the end, this paper points out that there is a trend in protective relaying equipment towards integrating relays together with microprocessors and intelligent electronic devices (IEDs). Finally all-digital intelligent relaying equipment with multi-function will play a leading role in modern protective relaying.