Analysis of Improper Action of Power Frequency Variation Impedance Protection Caused by Incorrect Wiring of Voltage Circuit
The present work was focused on causal analysis of improper action of power frequency variation impedance protection encountered by an actual transmission line when there occurred an external fault. It was found by on-site in-spection a mistaken connection of line protection voltage N600 circuit into open-delta voltage circuit which resulted in im-proper action of power frequency variation impedance protection.Then starting from the principle of power frequency vari-able impedance protection,the influence of voltage circuit's incorrect wiring on the impedance protection was analyzed by using fault potential diagram from the perspectives of three different fault situations,i.e.,internal fault,external fault and reverse fault. Moreover,effective pre-control measures were put forward so as to prevent the recurrence of such acci-dents.
voltage circuitpower frequency variationincorrect wiringimproper action of protection
万方数据
维普
