| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a disconnection detector which allows for detection of occurrence of a disconnection fault in any one phase on the power supply side or the load side, by attaching current sensors to any two phases of a high voltage three-phase distribution line, respectively. <P>SOLUTION: Secondary measurement voltage V of a pole transformer 3 installed in a three-phase distribution line 1, and currents Ia and Ic measured by two current sensors CT1, CT2 are detected. A determination is made that disconnection has occurred if any one of conditions 1-5 is satisfied. Condition 1: measurement voltage V is lower than a set level, condition 2: Ia or Ic=0(A), condition 3: ¾∠Ia-∠Ic¾=180°, condition 4: Ia/Ic≤0.6, condition 5: ¾∠Ia-∠Ic¾≥143°. <P>COPYRIGHT: (C)2013,JPO&INPIT |
