It is a market for AI-based servers, solar power, and electric vehicles that led to the recent growth of the large-capacity power supply industry. First of all, high frequency and large current of power conversion devices are in progress. In order to cope with the high functionality of such a power change device, various metal soft magnetic materials are continuously developed.
Amorphous soft magnetic alloy powder and nanocrystalline alloys have improved soft magnetic properties by eliminating magnetic anisotropy due to amorphization and minimizing magnetic deformation by composition control, and ribbons have been manufactured and used in rolled form. Soft magnetic materials due to high frequency are limited in ribbon form due to eddy current loss, and various studies are being conducted to manufacture powder using rapid cooling and use it as a high-frequency component by improving the specific resistance of the material through an insulation process. In this study, in order to overcome the above limitations, Fe-based Fe92.3Si3.5B3.0C0.7P0.5 (wt. %) amorphous metal powders with excellent magnetic properties were manufactured through a hybrid atomization method, and insulation was performed using a glass powder with various melting temperatures to improve high-frequency properties by improving eddy current loss. Finally, improved Fe-based Fe92.3Si3.5B3.0C0.7P0.5 (wt. %) amorphous magnetic materials were used to manufacture molding inductors using a magnetic paste that other researchers have not tried to overcome the limitations of inductors required by high-performance power conversion devices.
Fe-based Fe92.3Si3.5B3.0C0.7P0.5 (wt.%) amorphous metal powders manufactured by applying an improved high-speed water screen atomization process (HSWSA) were able to manufacture amorphous metal powders due to a similar cooling rate than powders manufactured by high-pressure water atomization, and Fe92.3Si3.5B3.0C0.7P0.5 (wt.%) amorphous metal powders manufactured by the HSWSA method were able to manufacture 166 emu/g (@1T) saturation magnetization value and showed excellent soft magnetic properties of 77 (Oe) coercive field (Hc) value.
Glass frits with a softening temperature between 260 and 600 degrees was applied to improve the high-frequency loss of the amorphous soft magnetic alloy powder. Fe92.3Si3.5B3.0C0.7P0.5 (wt.%) amorphous metal powders with excellent high-frequency properties with high powder resistance value (up to 6.3 X108Ωcm) and the lowest core loss value (less than 321 mW/㎤ with Bm=0.2T at 1 MHz) could be manufactured by forming a uniform and high non-resistance insulating layer with glass frits with high specific resistance value.
The electric vehicle OBC PFC inductor was simulated using the Ansys maxwell program, and the mold inductor was manufactured using the magnetic paste to compare and evaluate the inductor manufactured using the existing soft magnetic powder core. The inductance value (415 μH) of the inductor manufactured using Fe-based Fe92.3Si3.5B3.0C0.7P0.5 (wt. %) amorphous metal powder was about 14% higher than that of the inductance value (365 μH) of the inductor manufactured using crystalline metal powder. it is thought that the OBC inductor made of Fe92.3Si 3.5B 3.0C 0.7P 0.5 (wt. %) amorphous metal powder can manufacture an inductor with a smaller size, lighter weight, and lower heat generation than an inductor made of Fi-Si alloy-based or permalloy crystalline alloy powder. If PFC inductors using amorphous soft magnetic metal powder and magnetic paste are actively utilized by the process presented in this paper, it is expected to be applied very quickly as inductors and soft magnetic materials for inductors for high-performance strategic conversion devices in the future.