2020 年 44 巻 6 号 p. 129-132
Recently, wide-bandgap (WBG) power semiconductors made of silicon carbide (SiC) and gallium nitride (GaN) have been widely developed as high-speed switching devises. Many researchers have studied novel magnetic materials, such as nanocrystalline magnetic materials (NMMs), for low-loss electric motors and transformers. This study experimentally examines the hysteresis (B–H) curve and iron loss properties of the NMM core excited using a pulse width modulation (PWM) inverter at high carrier frequencies on the order of MHz with and without the dead time. For comparison, the magnetic properties of amorphous magnetic materials (AMMs) core are also evaluated. Particularly at high carrier frequencies (approximately 1 MHz), the iron loss of NMM and AMM cores significantly depends on the dead time. Compared with the case of the AMM core, the NMM core suppresses the increasing rate of iron losses caused by the dead time because the area of minor loops in NMM becomes small, particularly in high-frequency regions.
