| 摘要 |
<p>PURPOSE:To ensure accurate measurement of voltage without any effect of a current, etc., by providing a shield made of a magnetic material in each conductor and connecting an intermediate electrode of each phase which is set in correspondence to the conductor to a voltage sensor set within the shield. CONSTITUTION:A shield 5 made of a magnetic pipe is stored coaxially in the axial core of a conductor 3, and a voltage sensor 6 made of an electrooptic element is set within the shield 5. The sensor 6 is connected to an intermediate electrode 4 of each phase which is set in correspondence to the conductor 3 via electric connecting lines 8 and 9. When the sensor 6 is put into the axial core of the conductor 3, the magnetic field is completely eliminated and gives no effect at all. In the case of a 3-phase collective type, a magnetic field is generated by a current which flows through the conductor 3. However, the effect of this magnetic field can be completely eliminated since a bus conductor itself has a shilding effect and furthermore, the sensor 6 is put into the shield 5. In such a way, the voltage can be measured with high accuracy without receiving the effect of the voltage, current of another phase, etc.</p> |
