Inverter cores using FeMoCuSiB nanocrystalline soft magnetic alloys

Abstract

High power inverter cores using nanocrystalline FeMoCuSiB alloy annealed in transverse magnetic field were developed. The new cores show excellent properties, such as low core loss and high permeability, FeMoCuSiB alloy shows a high dynamic permeability of 24381 and a low dynamic coercive force H c of 6.16 A/M measured at 20 kHz. This high permeability and low coercive force can reduce the exciting electric current, thus the magnetic bias and waveform can be improved. Low temperature rise of core is due to using two special protection cases, one case is an aluminum box, the aluminum case has some divergent vanes which can send out the heat produced by the core and the vans can also be used as a support fixed to the bedplate. Another is nylon case with some wind holes on it, the heat produced by the core can easily be sent out through the wind holes. Accordingly, the new cores are expected to be applied in many applications as 20–100 kHz, high power main transformer for power-electronic devices.