Separation of Wear-Out Failure Modes of IGBT Modules in Grid-Connected Inverter Systems

Wear-out condition monitoring of IGBT modules with failure mode separation gives some benefits. First, it allows proactive maintenance plans. Further, depending on the failure mode, different proactive control strategies can be applied to inverters in order to improve the reliability and availability of power electronic systems. This paper proposes a new method for the separation of two representative wear-out failure modes of wire-bonded IGBT modules in a grid-connected inverter in real time. The proposed method requires just two preliminary I- V characterizations of IGBT modules. Further, only one monitoring parameter is used, and thus, it is cost-effective compared with using one more monitoring parameter in order to separate failure modes. Experimental results verify the validity and feasibility of the proposed method.