Power device modeling for power conversion circuit analysis

Power semiconductor devices are indispensable for inverters and DC-DC converters used in power conditioners for photovoltaic power generation and in motor drives for hybrid vehicles. Si power MOSFETs have been used for relatively low-voltage circuits, and Si IGBTs for medium-voltage and higher circuits. To achieve higher voltages and higher switching frequencies in power conversion circuits, it is necessary to go beyond the limits of conventional Si semiconductor devices to achieve further energy conservation and system miniaturization. The development of power semiconductor devices based on these wide bandgap semiconductors has been progressing. However, even if these new power semiconductor devices are used, their performance cannot be fully utilized if power conversion circuits are designed and fabricated by trial and error. Funaki Laboratory is characterizing and modeling power semiconductor devices for use in circuit design and evaluation in order to effectively apply these new power semiconductor devices to power conversion circuits. In particular, power conversion circuits need to be evaluated in operating regimes such as high voltage and high current, which have not been considered in conventional electronic circuits, and for this purpose, only physics-based modeling is performed based on semiconductor physics, electromagnetics, and circuit theory.

Research work