Takahiro Tera, DENSO CORPORATION
Recently, high power density and high efficiency of power converters are required. To reduce losses occurring in magnetic components, amorphous cut cores and nanocrystalline cut cores have been proposed.
For inductor applications, an air gap has to be inserted into the magnetic circuit to avoid saturation. However, when an air gap is inserted, fringing flux leaks out of the air gap. We use JMAG to clarify the behavior of the fringing flux.
In this report, we will introduce a modeling method of the cut core inductor and analysis result of the iron loss. The fringing flux induces in-plane eddy current and concentrates on the surface of the core. As a result, additional losses called gap loss occur. We introduce methods to reduce the gap loss.