Experimental investigation on the behaviour of IGBT at short-circuit during the on-state

Short-circuit withstand capability is an important feature of IGBTs for voltage-source inverter applications. Many manufacturers offer IGBTs with a guaranteed short-circuit withstand time. But in most cases, the short-circuit withstand capability is defined for the short-circuit type I. In this case, the load is already short-circuited when the IGBT is turned on. If the load is short-circuited when the IGBT carries current (short-circuit type II), the stress for the IGBT can be much higher. In this paper, the short-circuit type II behaviour of different IGBTs is investigated and a concept for a gate-drive circuit for improved short-circuit type II behaviour is introduced