Iron core for transformer and transformer

Abstract

By controlling variation in insulating coating thickness of grain-oriented electrical steel sheets with insulating coating used in an iron core, an increase in building factor caused by magnetic flux transfer in a lamination direction of the iron core is suppressed. An iron core for a transformer including a lamination of a plurality of single layers each including one or more sheets of grain-oriented electrical steel sheet with insulating coating. Each of the single layers has at least one steel sheet discontinuity extending in a direction that intersects with a direction of magnetic flux flow in the single layer. A standard deviation σ of a thickness of the insulating coating in a region between a steel sheet discontinuity of one of the single layers and a steel sheet discontinuity of another of the single layers adjacent in a lamination direction is 2 μm or more and 5 μm or less.

Dependencies are inferred from the claim text.