Coil structure, transformer, and power converter

#This application claims priority to Japanese Patent Application No. 2014-011966, filed on Jan. 27, 2014, the contents of which are hereby incorporated by reference.

#1. Technical Field

#The present disclosure relates to a coil structure, a transformer including the coil structure, and a power converter including the coil structure.

#FIG. 1 is a flowchart illustrating an example of a manufacturing method for a coil structure according to a first embodiment;

#FIG. 2A is a schematic perspective view illustrating an example of a conductor band;

#FIG. 2B is a schematic plan view of the conductor band shown in FIG. 2A;

#(Underlying Knowledge Forming Basis of the Present Disclosure)

#A coil constituted by magnet wire or litz wire is not suitable for a large-current use. In contrast, an edgewise coil constituted by conductive flat wire is suitable for a large-current use.

#An edgewise coil is constituted by flat wire which turns around a coil axis, such as that shown in FIG. 3A. The edgewise coil includes an inner peripheral edge closer to the coil axis and an outer peripheral edge farther away from the coil axis. The inner peripheral portion, which is shorter than the outer peripheral edge, has a lower electrical resistance than the outer peripheral edge. Accordingly, a current is more likely to concentrate on the inner peripheral portion. As a result, large resistive losses may occur in the edgewise coil.