АНГ 2 Relay protection / task_6.1

Кутонов В.С. 5А93

Answer the questions:

1. What is a purpose of auto recloser?

2. What is restoration time?

3. What factors determine a minimum time delay of auto recloser?

4. What will happen, if after auto reclosing a short circuit is still on the line?

5. How many attempts of reclosing are allowed?

6. What is main requirement for auto recloser installed on one the lines connected two part of the power system with individual sources of energy?

7. Is it possible to use non-three phase reclosing?

8. What Is the reason for using a synchro-check relay for auto reclosing?

9. In what cases auto recloser should not be applied?

10. What range for time delay there is for second, third and fourth attempts of auto recloser?

1. A recloser is a self-monitoring device for automatically disconnecting and reconnecting an AC circuit with a specified opening and reclosing sequence, followed by a reset or lockout. 2. Restoration time is the duration of an emergency repair or replacement of a failed element of the power supply system. 3. The minimum possible time for restoring the circuit by the action of reclosure is limited by a number of factors: the time of complete disconnection of the fault location from all power sources. 4. Recloser opens and blocks the fault delay, after tripping it must return to the ready state for a new tripping. 7. Yes, you can use non-three-phase reclosers 8. The synchro-check relay is needed to prevent the parallel operation of two electrical systems with generating sources.