Transient behavior of IGBTs submitted to fault under load conditions

The paper deals with the short circuit behavior during fault under load (FUL) conditions occurring on IGBT devices. The experimental switching transients in FUL with inductive load have been widely investigated. The devices have been tested in several working conditions accounting for the spread of the device characteristics, the parasitic due to the board layout, and the gate driving characteristics aiming to evaluate the switching performances and the influence of the parameters involved into the transient. The effect of the device temperature has been taken into account too. The experimental tests have been carried out using as a workbench a chopper circuit equipped with IGBT devices. As in medium and large power range converters the use of multiple string of IGBT devices is worth to be considered, the parallel and series connections experiencing FUL conditions have been also investigated.