Voltage Tunable Magnetoelectric Inductors With Improved Operational Frequency and Quality Factor for Power Electronics

Inductors find widespread use in various applications. Inductors with a large tunability of inductance and quality factor would lead to new paradigm on circuit designs. In this paper, we investigated the effect of ferromagnetic layer thickness on the performance of a magnetoelectric tunable inductor. Using chemical etching, the thickness of Metglas ribbons (2605SA1) can be reduced from 24 to about 8 μm, which dramatically reduces the eddy-current loss at higher frequencies. With the same total thickness, compared with inductor constructed with unthinned Metglas layers (2605CO), the maximum quality factor can be increased for 80%, and the operational frequency range can be extended for 10× to the >10 MHz range. An inductance tunable range of L_max/L_min = 370% was also achieved together with a significantly enhanced quality factor by ~3. Furthermore, with an inductor constructed with single thin Metglas (2605HB1M) layer, the maximum quality factor can be increased by 150% with single PZT slab and by 235% with double PZT slabs, and the operational frequency range can be extended by 100× with single slab and by 200× with double slabs, which makes these metallic magnetic ribbons tunable inductors competitive with ferrite materials in adaptive inductive power supply systems.