| 摘要 |
<p>PURPOSE: To accurately detect the generation of failure at the time of internal failure of a gas-blast circuit-breaker even in the case where pressure rise is generated by the arc between contacts at the time of opening a gas-blast circuit- breaker. CONSTITUTION: Pressure sensors S13, S23 are provided in circuit-breaker gas blocks 13, 23 of gas insulation switching devices 1, 2, and pressure rise detecting units D13, D23 for detecting pressure rise on the basis of the pressure sensors are provided. A protecting relay operation detecting unit 6 for detecting the operation of a protecting relay 3 is provided. A selecting unit 71 for selecting the output of the pressure rise detecting unit, which detected the first and the second pressure rise among the circuit-breaker gas blocks 13, 23 at the time of operating the protecting relay 3 is provided. A time difference detecting unit 72 for detecting time difference of the output of the selecting unit 71 is provided. A judging unit 73 for judging failure of the circuit-breaker gas block, of which pressure is firstly rose, in the case where the time difference exceeds the preset time difference monitor value is provided.</p> |
