Impact of implementation of auxiliary bias-windings on controllable inductors for power electronic converters

Magnetic devices are an important part of electronic converters. They can be used to control some properties of the converters. There are three different control methods using an auxiliary bias-winding. In the presented paper, the impact of the implementation of the auxiliary bias-winding was studied for mixed biasing. Seven different designs were investigated in small signal measurements and 3D-FEM-simulations. The results were proven by calculated results of equivalent diagram circuits, which have been developed. Regarding the standard crosswise current arrangement all designs show the same results. In a horizontal aux. current arrangement, the effect of the VAG technique is mitigated. Investigations of a vertical aux. current arrangement results in an unsymmetrical magnetization curve.