Impacts of Diode Surge Currents on Reverse Conducting IGBT Controlled by Optimized Gate-Drive Unit

Diode surge currents constitute a challenging demand in any inverter structure. Especially, while using an improved gate-drive control for RC-IGBTs with an implemented blanking time to delay the transition from IGBT- to diode-mode. Therefore, HV-measurements with 6.5 kV RC-IGBTs were accomplished to ensure safe operation of this particular gate-drive concept. Furthermore, a compensation technique to avoid excessive forward recovery voltage drop is introduced.