Controllable inductor

摘要

A controllable inductor including a tubular core, a main winding (1) surrounding the core, a control winding running substantially axially to the core and an element (3) surrounding the core and arranged to support the main winding wound outside thereof in radial layers. The element includes means arranged to provide channels (19) partly defined by the radially inner turn of the main winding. Said channels are communicating with spacings between said layers (2). A member is arranged to generate a flow of air in the channels and through the spacings of the layers for cooling the main winding.