Variable Inductor Operation and Applications in Power Electronics

Variable inductors (VIs) are magnetic elements whose inductance can be controlled by an analog signal, usually a DC current injected into an auxiliary winding. The DC current generates a DC magnetic flux density that can modulate the magnetic permeability of the core. This modulation ultimately generates a change on the effective inductance of the main winding of the VI. Thus, VIs are particularly interesting because they can provide and additional degree of freedom in the design of power electronics converters. Example of applications are DC-DC converters, resonant inverters, electronic ballasts, LED drivers, power factor correctors, MPPT converters for solar panels, wireless power transfer, and so on. In this lecture, an introduction to VI will be presented, showing the most important VI structures and their operation. The VI design and modelling will also be dealt with. Next, VI modeling based on SPICE simulators will be presented. Finally, some applications of VIs will be illustrated with especial focus on LED lighting applications.

Biography:
J. Marcos Alonso (SM’03) received the M. Sc. Degree and Ph.D. Degree (with honors) both in electrical engineering from the University of Oviedo, Spain, in 1990 and 1994 respectively. Since 2007, he is a full Professor of the Electrical Engineering Department of the University of Oviedo.
Prof. Alonso is co-author of more than 400 journal and conference publications, including more than 100 publications in highly referenced journals. His research interests include lighting applications, dc-dc converters, power factor correction, resonant inverters and power electronics in general. He is the holder of 8 national and international patents.
Prof. Alonso holds 9 IEEE awards. He serves as an Associate Editor of the IEEE Transactions on Power Electronics and IEEE Journal on Emerging and Selected Topics on Power Electronics. He was the Chair of the IEEE IAS Industrial Lighting and Displays Committee (ILDC) for the term 2017-2018.