Yusuke Kikuchi
Professor | Ph.D. in Engineering
Electrical and Electronic Engineering Course
Plasma and Discharge Engineering Research Group
Electrical engineering underpins the transition to a decarbonized society, spanning foundational subjects such as circuits and electromagnetism as well as industry-oriented topics such as motors, generators, and power generation. Within this field, Yusuke Kikuchi investigates the interactions between high-energy discharge and plasma states and the materials they encounter, drawing on power-conversion circuit technologies such as inverters to support this work.
Improving Performance of SiC Inverter-Driven Motors
What students can learn
This theme introduces power-conversion circuit techniques for high-voltage, nanosecond-pulse power supplies built around SiC inverters, together with hands-on experience in high-voltage handling, discharge phenomena, insulation, power-supply control, measurement, and discharge simulation.
Motors account for roughly half of Japan's electricity consumption, so reducing their power consumption through inverter control contributes significantly to energy conservation and the mitigation of global warming. Next-generation power semiconductors such as SiC enable the fast switching and high voltages required for electric vehicles and electric aircraft, yet the repeated nanosecond-scale surge voltages they generate can trigger partial discharge and insulation degradation within motor coils. This research investigates the mechanisms of partial discharge under SiC inverter voltages and aims to develop long-life nanocomposite wires that resist such degradation.
Surface Treatment Using Sub-Atmospheric-Pressure Plasma: High-Speed Film Deposition and Surface Nanostructuring
What students can learn
In this theme, students gain experience generating high-repetition nanosecond-pulse glow discharge and DC arc discharge under sub-atmospheric pressure with SiC inverter power supplies, and in analyzing the resulting thin films and surface nanostructures.
Plasma-based surface treatment is widely used across industry, including in semiconductor manufacturing. This research employs sub-atmospheric-pressure plasma, which achieves high plasma density without the need for costly vacuum equipment, to deposit diamond-like carbon films and form fibrous nanostructures on metal surfaces at high speed. Such plasma treatment can blacken tungsten surfaces and produce fibrous nanostructures with substantially increased surface area, a property that may prove useful in applications such as photocatalysis.
