Experimental optimisation of high power IGBT modules performances working at the edges of their safe operating area

An experimental characterization of new 3300 V - 1200 A IGBT modules both at high temperature and for output currents beyond SOA, at turn-off and in short circuit conditions, is presented. Moreover a new driving strategy that improves, in comparison with conventional driving methods, IGBT turn-on on inductive load, in terms of power dissipation, is reported. Results demonstrate that, in principle, it is possible to operate at larger current than RBSOA limits and at temperature of 145 /spl deg/C. As regard turn-on operation, up to 37% dissipated energy reduction can be obtained with the innovative on-gate control. All the experimental study has been performed by means of a non-destructive experimental set-up, where IGBT modules are switched in presence of a protection circuit that is able to prevent device failure at the occurrence of any possible unstable behaviour.