| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a zero-phase-sequence current transformer which can improve the screening effect of a shield member and reduce unnecessary output. <P>SOLUTION: A zero-phase-sequence current transformer comprises: a core 11 made up of annular magnetic materials; a troidal coil 12 wound along the circle of the core 11; a shield member made up of the magnetic materials positioned around the core 11 and the coil 12. The shield member comprises: a first shield member 21 by an inner-upper-side shield 13 and an inner-lower-side shield 14 positioned near the core 11; a second shield member 22 by an outer-top-face shield 15, an outer-underside shield 16, an inner-periphery shield 17, and an outer-periphery shield 18. The first shield member 21 and the second shield member 22 have different magnetic characteristics and the second shield member 22 has higher saturation magnetic flux density than the first shield member 21. <P>COPYRIGHT: (C)2012,JPO&INPIT |
