Low voltage high current trench-gate MOSFET inverter for belt starter generator applications

The paper deals with a last generation of trench-gate low voltage MOSFET application on the development of high current inverter legs for AC motor driver. Each inverter leg is made of several MOSFET paralleled devices. An actual three phase inverter made with six MOSFETs for switch is applied to drive a belt starter generator in hybrid electrical vehicle. In the paper an experimental evaluation of the inverter is carried out. The main issues of the power devices impact on the realization of the high current inverter are treated. Dynamic performances, power losses and thermal capability of the paralleled MOSFET devices in this kind of automotive application are presented and discussed. Finally, repetitive short circuit tests results are focused to validate the effectives of the inverter solution proposed for the motors driver in low voltage high current applications.