| 摘要 |
PURPOSE:To remove faulty section without delaying trip when a circuitbreaker is thrown in under inner fault condition by providing a high set value overcurrent relay employs only the current at its terminal as an operational amount. CONSTITUTION:A high set value overcurrent relay employing the current only at its terminal as an operation amount is additionally provided to a circuit comprising a combination of a current operation relay 3A and an under voltage relay 13A. A trip circuit for taking AND of an output 19A from a HOC 17A which is made effective through an AND gate 26 only during the time limit of an off-delay timer 23 after reception of a circuitbreaker throw-in command and an output 18A from the current operation relay 3A is also provided additionally. Trip command for a circuitbreaker cA can be provided quickly, even if there is an inner fault in a transmission line 1 when the circuit breaker is thrown in, by employing the output from the HOC 17A. |
