Development of High-Density and Low-Loss Powder Magnetic Core for Reactor in Hybrid Vehicles

Abstract

A magnetic core of a reactor applied to the boost converter of hybrid vehicle was developed. The core is made of High-Density Magnetic Composite, which is a kind of the powder magnetic core. A great cost reduction was achieved while keeping the magnetic properties equal to conventional magnetic steel. In order to achieve both high magnetic flux density and mechanical properties of the core, high compaction density and high bending strength were coped with by developed warm compaction technique using die wall lubrication. The great decrease of a core loss was achieved by adopting the Fe-Si alloy, developing the particle shape of the raw material powder made by the new controlled atomization method and enabling the annealing at the high temperature.