The countermeasure for global warming by carbon dioxide is indispensable to construct sustainable society. The Japanese government establish a goal of 80% carbon dioxide emission reduction until 2050 based on 2005 level. It is not easy to achieve this goal with keeping the current standard of living. There are two approaches. One is to create energy by renewable, which does not emit carbon dioxide. The other is to reduce energy consumption by energy saving. These approaches require electric power conversion and control, because the current energy usage is mainly with electricity. Power electronics realize this requirement. Power electronics converts electric power with utilizing semiconductor device as an on off switch. The power electronics circuit must combine semiconductor device and passive components, e.g. capacitor and inductor, because simple semiconductor device cannot achieve power conversion. The fast switching operation of semiconductor device enables to high frequency switching operation and it reduces the required amount of passive component of capacitor and inductor. Therefore, high frequency switching operation lead to miniaturization and weight saving of power conversion circuit and system. The conduction loss in the wiring can be made less by raising circuit voltage and reducing current for same power utilization. However, there is difficulty in conventional high voltage semiconductor device for its slow turn on and off switching operation and large conduction loss. Therefore, wide band gap semiconductor has been attracting attention, e.g. SiC and GaN, as an instead of conventional Si semiconductor. The low conduction loss and fast switching operation semiconductor device can be realized by utilizing these wide band gap semiconductors. But, the wide band gap semiconductor device cannot be made full use by simply replacing conventional Si semiconductor device. The electromagnetic noise accompanied with switching operation of semiconductor device becomes large for fast switching of high voltage and large current. The electromagnetic noise causes malfunction of peripheral equipment, and may influence on its own operation.

Therefore, power conversion circuit is required to be designed not to generate electromagnetic noise. Power module is necessary for low noise power conversion circuit design.
The modularization of power device and peripheral component enables to raise power density of power conversion system by miniaturization and suppresses electromagnetic noise generation by reducing parasitic inductance in the circuit. But, there is a difficulty of increasing thermal density by miniaturization, because loss in wide band gap semiconductor device does not disappear. Then, system design with composite region of electricity and thermal is required. The design of material, topology and fabrication of passive component is important to reduce loss in capacitor and inductor in high switching frequency operation and makes circuit operation closer to ideal operation. Our research group researches the required design of power module and system to realize high performance power electronics system and demonstrates the advantage of developed technology.