Performance of a prototype power transformer constructed by nanocrystalline Fe-Co-Si-B-P-Cu soft magnetic alloys

To clarify the feasibility and performance of Fe_81.2Co₄Si_0.5B_9.5P₄Cu_0.8 alloy (with trade name NANOMET^®) for electrical power applications, a prototype transformer was constructed. After surface treatment, as-quenched ribbons with a constant width of 50 mm and a thickness of ∼30 μm were wound into a toroidal shape. Nanocrystallization of toroidal core was performed by immersing it in a salt at 673 K for 180 s. The transformer constructed in the present work exhibit low core loss similar to the transformer constructed by a commercial Fe-based amorphous alloy. In spite of issues related to the annealing/nano-crystallization of the core, the feasibility for commercialization of NANOMET in power transformer applications can be confirmed. We believe the potential of NANOMET as core material for next generation of power transformer seems to be huge.