METHOD FOR PROTECTING AND COOPERATING DISTANCE PROTECTIVE RELAY APPARATUS AND DISTANCE PROTECTIVE RELAY APPARATUS

PROBLEM TO BE SOLVED: To accelerate a fault detecting operation in a first stage region of a distance relaying and protecting apparatus. SOLUTION: The distance protective relay apparatus includes a timer 4 for delaying an operation signal of a mho element 2 at t1 time, an AND gate 3 for obtaining an AND of the output of the timer 4 and an operation signal of a reactance element 1, a timer 7 for delaying the output of the AND gate 3 at a t2 time, a timer 5 for delaying an ON operation of the output of the timer 4 at t3 time and delaying an OFF operation at t4 time, and an AND gate 6 for obtaining an AND of the inverted signal of the output of the timer 5 and the output of the AND gate 3. The output of the timer 7 and the AND gate 6 are used as operation signals of a first stage distance relay, and set to t1>(maximum value of resetting time of a reactance element-minimum value of an operating time of the mho element), t2>(a time from output ON of the timer 4 to a removal of an external fault), t3>(time from output ON of the timer 4 to removal of an external fault), and t4>ät2-(maximum value of resetting time of mho element-minimum value of operating time of reactance element)}. COPYRIGHT: (C)2005,JPO&NCIPI