Optimized IGBT technology for mild hybrid vehicles

A new IGBT (Insulated-Gate Bipolar Transistor) technology with a blocking voltage capability of 400V was developed in order to further increase the improvements of hybrid vehicles in terms of fuel efficiency. Conduction and switching losses are significantly reduced by means of using an ultra-thin wafer technology (approximately 40μm thickness) having a direct impact on the overall efficiency. A complete inverter prototype was designed and used to compare the performance of state of the art 650V IGBTs and the new 400V technology. The results showed a significant decrease of the power losses using 400V IGBTs, which could be used to increase the efficiency (less fuel consumption), reduce cost (less chip area or cooling efforts) or/and increase the power density of the system (under same conditions, higher output power possible). Due to its reduced blocking voltage, this new IGBT is mostly suitable for mild hybrid vehicles with working voltages up to approximately 200V.