Tokyo, Japan – Nissan Motor Company has announced the development of the world’s first inverter using SiC (silicon carbide) diodes for vehicle use. The technology is being launched in tests using an X-Trail FCV (fuel cell vehicle) but can also be applied to electric and hybrid-electric vehicles currently under development by the automaker.
Inverters on electric-powered vehicles control electricity coming from the power source, and their size has often set limitations on vehicle layout. The newly-developed inverter uses SiC for the diodes, along with a new Nissan-developed heterojunction diode, which when combined reduce the overall size and weight of the inverter and dramatically improve its reliability. Previous silicon diodes used in electric-powered vehicles created power losses and required heat dissipation countermeasures; the company said the newly-developed diode provides higher power efficiency with improved heat resistance and reliability to create a high breakdown voltage large-capacity inverter. The new SiC inverter’s diode surface has been reduced by 70 per cent, while circuit energy efficiency has been improved by 20 per cent, in comparison to previous diodes. The simplification of cooling mechanisms allows for further size and weight reductions by 15 to 20 per cent.
Nissan said that the inverter is regarded as one of the key technologies in electric-powered vehicle development, along with the motor and battery. The company aims to further reduce the inverter size by employing SiC diodes on the transistor.