Transverse flux strip heating with DC edge saturation

摘要

Induction heating apparatus and methods are disclosed for selective workpiece heating such as strip heating, in which DC windings around one or more laminations proximate to a workpiece edge are selectively energized using DC electrical power for controlled partial or full saturation of the one laminations to control edge overheating in a transverse flux induction heating system, in which certain implementations further employ a copper shield between the induction heating coil and the strip workpiece proximate the edge of the workpiece to control the edge heating effect.

主权项

1. An induction heating apparatus for induction heating at least a portion of a select portion of a strip workpiece traveling along a process direction relative to the induction heating apparatus, the workpiece having opposite first and second workpiece sides and first and second workpiece edges, the induction heating apparatus comprising:
a first coil structure spaced from and facing the first workpiece side and extending between the first and second workpiece edges; an AC supply operatively coupled with the first coil structure to provide AC current to energize the first coil structure for heating at least a portion of the first workpiece side; a plurality of laminations at least partially surrounding a first portion of the first coil structure leaving an unobstructed second portion of the first coil structure facing the first workpiece side, the individual laminations including laminated structures extending along the process direction, the individual laminations parallel to and spaced from an adjacent lamination along a cross-process direction between the first and second workpiece edges; windings extending around at least portions of a first set of the plurality of laminations; and a DC supply coupled with the windings and operative to selectively provide DC current to individual windings to at least partially saturate a magnetic field associated with individual ones of the corresponding laminations of the first set; and a controller operatively coupled with the DC supply to control individual DC excitation of the individual windings for selectively saturating the individual ones of the corresponding laminations of the first set to control induction heating of the first and second workpiece edges.