Title:
CURRENT TRANSFORMER CORE, METHOD FOR MANUFACTURING SAME, AND DEVICE EQUIPPED WITH SAID CORE
Document Type and Number:
WIPO Patent Application WO/2016/017578
Kind Code:
A1
Abstract:
A method for manufacturing a current transformer core comprises: a step of preparing a core material obtained by winding or laminating an Fe-based amorphous alloy ribbon capable of being nano-crystallized with a thickness of 15 μm or less; a longitudinal magnetic field heat treatment step of performing a heat treatment on the core material to form a core while applying a magnetic field of 100 A/m or more in a magnetic path direction of the core material; and a transverse magnetic field heat treatment step of, after the longitudinal magnetic field heat treatment step, performing a heat treatment on the core while applying a magnetic field in a direction perpendicular to the magnetic path direction of the core, thereby forming a core. When, under the condition that an AC magnetic field having a frequency of f = 50 Hz and an amplitude of H = 1.0 A/m is applied, an amplitude permeability of the core measured at a temperature T (°C) is denoted by μr (T) and the amplitude permeability μr (T) obtained in the longitudinal magnetic field heat treatment step is denoted by μr (max) (T), the amplitude permeability μr (25) is adjusted in the transverse magnetic field heat treatment step to a value between 0.4 × μr (max) (25) and 0.9 × μr (max) (25).
Inventors:
HAGIWARA KAZUHIRO
Application Number:
PCT/JP2015/071243
Publication Date:
February 04, 2016
Filing Date:
July 27, 2015
Export Citation:
Assignee:
HITACHI METALS LTD (JP)
International Classes:
H01F38/28; H01F1/16; H01F41/02
Foreign References:
JP2006525655A | 2006-11-09 | |||
JPH0885821A | 1996-04-02 | |||
JP2859286B2 | 1999-02-17 | |||
JP2710949B2 | 1998-02-10 |
Other References:
See also references of EP 3176797A4
Attorney, Agent or Firm:
OKUDA SEIJI (JP)
Seiji Okuda (JP)
Seiji Okuda (JP)
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