Rebirth of negative-sequence quantities in protective relaying with microprocessor-based relays

摘要: This paper focuses on the uses of negative-sequence quantities in protective relaying. The emphasis is numerical relays since they have facilitated calculation symmetrical components. Negative-sequence (the voltage and current denoted by V2 12) are very useful simplicity these modern has reinforced their use theory methods used relaying devices. begins with discussion some implementations filters older relays. Next a brief review components an analysis unbalanced faults power systems. leads to characteristics illustrations how Because generally involves component theory, makes references throughout other two (positive-sequence zero-sequence).